CFD-based Thrombotic Risk Assessment in Kawasaki Disease Patients with Coronary Artery Aneurysms

NASA Astrophysics Data System (ADS)

Sengupta, Dibyendu; Kung, Ethan; Kahn, Andrew; Burns, Jane; Marsden, Alison

2012-11-01

Coronary aneurysms occur in 25% of untreated Kawasaki Disease (KD) patients and put patients at increased risk for myocardial infarction and sudden death. Clinical guidelines recommend using aneurysm diameter >8 mm as the arbitrary criterion for treating with anti-coagulation therapy. This study uses patient-specific modeling to non-invasively determine hemodynamic parameters and quantify thrombotic risk. Anatomic models were constructed from CT angiographic image data from 5 KD aneurysm patients and one normal control. CFD simulations were performed to obtain hemodynamic data including WSS and particle residence times (PRT). Thrombosis was clinically observed in 4/9 aneurysmal coronaries. Thrombosed vessels required twice as many cardiac cycles (mean 8.2 vs. 4.2) for particles to exit, and had lower mean WSS (1.3 compared to 2.8 dynes/cm2) compared to vessels with non-thrombosed aneurysms of similar max diameter. 1 KD patient in the cohort with acute thrombosis had diameter < 8 mm. Regions of low WSS and high PRT predicted by simulations correlated with regions of subsequent thrombus formation. Thrombotic risk stratification for KD aneurysms may be improved by incorporating both hemodynamic and geometric quantities. Current clinical guidelines to assess patient risk based only on aneurysm diameter may be misleading. Further prospective study is warranted to evaluate the utility of patient-specific modeling in risk stratifying KD patients with coronary aneurysms. NIH R21.

Current Perspectives in Imaging Modalities for the Assessment of Unruptured Intracranial Aneurysms: A Comparative Analysis and Review.

PubMed

Turan, Nefize; Heider, Robert A; Roy, Anil K; Miller, Brandon A; Mullins, Mark E; Barrow, Daniel L; Grossberg, Jonathan; Pradilla, Gustavo

2018-05-01

Intracranial aneurysms (IAs) are pathologic dilatations of cerebral arteries. This systematic review summarizes and compares imaging techniques for assessing unruptured IAs (UIAs). This review also addresses their uses in different scopes of practice. Pathophysiologic mechanisms are reviewed to better understand the clinical usefulness of each imaging modality. A literature review was performed using PubMed with these search terms: "intracranial aneurysm," "cerebral aneurysm," "magnetic resonance angiography (MRA)," computed tomography angiography (CTA)," "catheter angiography," "digital subtraction angiography," "molecular imaging," "ferumoxytol," and "myeloperoxidase". Only studies in English were cited. Since the development and improvement of noninvasive diagnostic imaging (computed tomography angiography and magnetic resonance angiography), many prospective studies and meta-analyses have compared these tests with gold standard digital subtraction angiography (DSA). Although computed tomography angiography and magnetic resonance angiography have lower detection rates for UIAs, they are vital in the treatment and follow-up of UIAs. The reduction in ionizing radiation and lack of endovascular instrumentation with these modalities provide benefits compared with DSA. Novel molecular imaging techniques to detect inflammation within the aneurysmal wall with the goal of stratifying risk based on level of inflammation are under investigation. DSA remains the gold standard for preoperative planning and follow-up for patients with IA. Newer imaging modalities such as ferumoxytol-enhanced magnetic resonance imaging are emerging techniques that provide critical in vivo information about the inflammatory milieu within aneurysm walls. With further study, these techniques may provide aneurysm rupture risk and prediction models for individualized patient care. Copyright © 2018 Elsevier Inc. All rights reserved.

Secular pattern of aneurismal rupture with the lunar cycle and season.

PubMed

Banfield, Jillian C; Abdolell, Mohamed; Shankar, Jai S

2017-02-01

Background The lunar cycle and seasons may be associated with rates of rupture of intracranial aneurysms, but the literature is mixed. Studies of the association between the lunar cycle and rates of aneurysm rupture used the eight qualitative moon phases. The purpose of this study was to assess any association of aneurysm rupture with the lunar cycle and with the season. Materials and methods We retrospectively reviewed all cases of subarachnoid haemorrhage secondary to ruptured intracranial aneurysm treated with endovascular coiling in our institution over a 10-year period. We included only cases with a known rupture date. We used the degree of illumination of the moon to quantitatively code the lunar cycle. Results A total of 212 cases were included in our analyses. The odds of aneurysm rupture were significantly greater ( p < 0.001) when the moon was least (new moon) and most (full moon) illuminated, as compared to the middle of the lunar cycle. The odds of rupture tended to be higher ( p = 0.059) in the summer, compared to autumn. Conclusions The odds of aneurysm rupture were greater when the moon was least illuminated (new moon) and most illuminated (full moon), compared to the middle of the lunar cycle.

Study of Cognitive Impairments Following Clipping of Ruptured Anterior Circulation Aneurysms.

PubMed

Mohanty, Manju; Dhandapani, Sivashanmugam; Gupta, Sunil Kumar; Shahid, Adnan Hussain; Patra, Debi Prasad; Sharma, Anchal; Mathuriya, Suresh Narayan

2018-06-16

The cognitive impairments following treatment of ruptured aneurysms have often been underestimated. This study was to assess their prevalence and analyze various associated factors. Patients who were operated for ruptured anterior circulation aneurysms and discharged in Glasgow outcome scale 4-5 were studied at 3 months for various cognitive impairments. Continuous scales of memory (recent, remote, verbal, visual and overall memory), verbal fluency (phonemic and category fluency) and others were studied in relation to various factors. Univariate and multivariate analyses were performed using SPSS21. There were a total of 87 patients included in our study. Phonemic fluency was the most affected noted in 66% of patients. While 56% had some memory related impairments, 13 (15%) and 6 (7%) had moderate and severe deficits in recent memory, and 19 (22%) and 12 (14%) had moderate and severe deficits in remote memory respectively. Patients operated for anterior cerebral artery (ACA) aneurysms have significantly greater impairments in recent (34% vs 8%) and remote memory (43% vs 28%) compared to the rest, both in univariate (P values 0.01 & 0.002 respectively) and multivariate analyses (P values 0.01 & 0.03 respectively). ACA related aneurysms also had significantly greater independent impairments in phonemic fluency (P-value 0.04), compared to others. The clinical grade had a significant independent impact only on remote memory (P-value 0.01). Cognitive impairments are frequent following treatment of ruptured anterior circulation aneurysms. Impairments in recent memory, remote memory, and phonemic fluency are significantly greater following treatment of ACA related aneurysms, compared to others, independent of other factors. Copyright © 2018. Published by Elsevier Inc.

Outcomes for Symptomatic Abdominal Aortic Aneurysms in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP)

PubMed Central

Soden, Peter A.; Zettervall, Sara L.; Ultee, Klaas H.J.; Darling, Jeremy D.; Buck, Dominique B.; Hile, Chantel N.; Hamdan, Allen D.; Schermerhorn, Marc L.

2016-01-01

Introduction Historically symptomatic AAAs were found to have intermediate mortality compared to asymptomatic and ruptured AAAs but, with wider EVAR use, a more recent study suggested mortality of symptomatic aneurysms were similar to asymptomatic AAAs. These prior studies were limited by small numbers. The purpose of this study is to evaluate the mortality and morbidity associated with symptomatic AAA repair in a large contemporary population. Methods All patients undergoing infrarenal AAA repair were identified in the 2011–2013 ACS-NSQIP, Vascular Surgery targeted module. We excluded acute conversions to open repair and those for whom the surgical indication was embolization, dissection, thrombosis, or not documented. We compared 30-day mortality and major adverse events (MAE) for asymptomatic, symptomatic, and ruptured AAA repair, stratified by EVAR and open repair, with univariate analysis and multivariable logistic regression. Results 5502 infrarenal AAAs were identified, 4495 asymptomatic (830 open repair, 3665 [82%] EVAR), 455 symptomatic (143 open, 312 [69%] EVAR), and 552 ruptured aneurysms (263 open, 289 [52%] EVAR). Aneurysm diameter was similar between asymptomatic and symptomatic AAAs, when stratified by procedure type, but larger for ruptured aneurysms (EVAR symptomatic 5.8cm ±1.6 vs. ruptured 7.5cm ±2.0, P<.001; open repair symptomatic 6.4cm ±1.9 vs. ruptured 8.0cm ±1.9, P<.001). The proportion of females was similar in symptomatic and ruptured AAA (27% vs. 23%, P=.14, respectively), but lower in asymptomatic AAA (20%, P<.001). Symptomatic AAAs had intermediate 30-day mortality compared to asymptomatic and ruptured aneurysms after both EVAR (asymptomatic 1.4% vs. symptomatic 3.8%, P=.001; symptomatic vs. 22% ruptured, P<.001) and open repair (asymptomatic 4.3% vs. symptomatic 7.7% , P=.08; symptomatic vs. 57% ruptured, P<.001). After adjustment for age, gender, repair type, dialysis dependence, and history of severe COPD, patients undergoing repair of symptomatic AAAs were twice as likely to die within 30-days compared to those with asymptomatic aneurysms (OR 2.1, 95%CI 1.3–3.5). When stratified by repair type the effect size and direction of the odds ratios were similar (EVAR OR 2.4, CI 1.2–4.7; open repair OR 1.8, CI 0.86–3.9), although not significant for open repair. Patients with ruptured aneurysms had a sevenfold increased risk of 30-day mortality compared to symptomatic patients (OR 6.5, CI 4.1–10.6). Conclusion Patients with symptomatic AAAs had a two-fold increased risk of perioperative mortality, compared to asymptomatic aneurysms undergoing repair. Furthermore, patients with ruptured aneurysms have a seven-fold increased risk of mortality compared to symptomatic aneurysms. PMID:27146791

Vein graft aneurysms following popliteal aneurysm repair are more common than we think.

PubMed

Sharples, Alistair; Kay, Mark; Sykes, Timothy; Fox, Anthony; Houghton, Andrew

2015-10-01

True infrainguinal vein graft aneurysms are reported infrequently in the literature. We sought to identify the true incidence of these graft aneurysms after popliteal aneurysm repair and identify factors which may increase the risk of such aneurysms developing. Using a prospectively compiled database, we identified patients who underwent a popliteal aneurysm repair between January 1996 and January 2011 at a single district general hospital. Patients were routinely followed up in a graft surveillance programme. Out of 45 patients requiring repair of a popliteal aneurysm over a 15-year period, four (8.8%) patients developed aneurysmal graft disease. Of the patients who developed graft aneurysms, all had aneurysmal disease at other sites compared with 18 (45.0%) patients who did not develop graft aneurysms. Patients with graft aneurysms had a mean of 1.60 aneurysms elsewhere compared to 0.58 in patients with non-aneurysmal grafts (P = 0.005). True vein graft aneurysms occur in a significant number of patients following popliteal aneurysm repair. Our data would suggest this to be more likely in patients who have aneurysms elsewhere and therefore a predisposition to aneurysmal disease. It may be appropriate for patients with aneurysms at other sites to undergo more prolonged post-operative graft surveillance. © The Author(s) 2014.

Influence of hemodynamic factors on rupture of intracranial aneurysms: patient-specific 3D mirror aneurysms model computational fluid dynamics simulation.

PubMed

Lu, G; Huang, L; Zhang, X L; Wang, S Z; Hong, Y; Hu, Z; Geng, D Y

2011-08-01

Hemodynamics factors play an important role in the rupture of cerebral aneurysms. The purpose of this study was to evaluate the impact of hemodynamic factors on the rupture of the MANs with 3D reconstruction model CFD simulation. RDSA was performed in 9 pairs of intracranial MANs. Each pair was divided into ruptured and unruptured groups. The hemodynamic factors of the aneurysms and their parent arteries were compared. There was a significant difference in the WSS at peak systole between the regions of the aneurysms and their parent arteries in the ruptured group (ie, 6.49 ± 3.48 Pa versus 8.78 ± 3.57 Pa, P =.015) but not in the unruptured group (ie, 9.80 ± 4.12 Pa versus 10.17 ± 7.48 Pa, P =.678). The proportion of the low WSS area to the whole area of the aneurysms was 12.20 ± 18.08% in the ruptured group and 3.96 ± 6.91% in the unruptured group; the difference between the 2 groups was statistically significant (P =.015). The OSI was 0.0879 ± 0.0764 in the ruptured group, which was significantly higher than that of the unruptured group (ie, 0.0183 ± 0.0191, P =.008). MANs may be a useful disease model to investigate possible causes linked to ruptured aneurysms. The ruptured aneurysms manifested lower WSS compared with their parent arteries, a higher proportion of the low WSS area to the whole area of aneurysm, and higher OSI compared with the unruptured aneurysms.

Angiographic and epidemiological characteristics associated with aneurysm remnants after microsurgical clipping

PubMed Central

Dellaretti, Marcos; da Silva Martins, Warley Carvalho; Dourado, Jules Carlos; Faglioni, Wilson; Quadros, Ricardo Souza; de Souza Moraes, Vítor Vieira; de Souza Filho, Carlos Batista Alves

2017-01-01

Background: Despite new techniques for the treatment of cerebral aneurysms, the percentage of aneurysm remnants after surgical intervention seems to be relatively constant. The objective of this study was to assess angiographic and epidemiological features associated with aneurysm remnants after microsurgical clipping. Methods: This study was conducted from February 2009 to August 2012 on a series of 90 patients with 105 aneurysms referred to the Santa Casa of Belo Horizonte who were surgically treated and angiographically controlled. Results: Surgical clipping was considered incomplete in 13.3% of the aneurysms. The mean age of cases with an aneurysm remnant was 57.5 years, whereas the mean age without aneurysm remnant was 49.7 years (P = 0.02). Aneurysm remnants were detected more frequently on the internal carotid artery, nevertheless, no statistically significant differences were verified when comparing the locations. Aneurysm size in the preoperative angiography verified that the mean size of aneurysms operated was 6.56 mm, such that in cases showing a postoperative remnant, the mean size was 9.7 mm and in cases with complete clipping it was 6.08 mm (P = 0.02). Postoperative angiography showed that, in cases with residual aneurysm, the number of clips used was higher – a mean of 1.8 for complete clipping and 3.1 for incomplete clipping (P < 0.001). Conclusions: Aneurysm size and patient age showed significant correlations with residual intracranial aneurysm. The mean number of clips used was higher in cases with incomplete occlusion. PMID:28904825

Clinical and angiographic outcomes after stent-assisted coiling of cerebral aneurysms with Enterprise and Neuroform stents: a comparative analysis of the literature.

PubMed

King, Brent; Vaziri, Sasha; Singla, Amit; Fargen, Kyle M; Mocco, J

2015-12-01

The most widely used intracranial stents for stent-assisted coiling are Neuroform (NEU) and Enterprise stents (ENT). This study compares published outcomes between the ENT and NEU coil-assist systems and comments on the published safety and efficacy of stent-assisted coiling in general. A literature search was performed through PubMed for all published series of ENT or NEU stent-assisted coiling of cerebral aneurysms from 2004 to 2014. All studies including 10 or more published cases of stent-assisted coiling with ENT or NEU were included. 47 studies met the inclusion criteria, containing 4238 aneurysms in 4039 patients. 2111 aneurysms were treated with NEU and 2127 were treated with ENT. Mean follow-up was 14.1 months. Overall, thromboembolic events occurred in 6.4% of aneurysms, intracranial hemorrhage (ICH) in 2.6%, permanent morbidity in 3.9%, and mortality in 2.3%. Initial and final 100% angiographic occlusion was seen in 53% and 69% of patients, respectively. Deployment failures (p<0.001), ICH (p=0.001), mortality among all patients (p=0.03), and recanalization (p=0.02) were more commonly reported in NEU treated aneurysms. The ENT system was also associated with higher reported complete occlusion at follow-up (p<0.001). This literature review represents the largest and most robust comparison of stent-assisted coiling devices to date, containing over 4200 aneurysms in more than 4000 patients. Comparative analyses demonstrate that both devices are reported to be safe and effective with comparable permanent morbidity. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Morphological and clinical risk factors for posterior communicating artery aneurysm rupture.

PubMed

Matsukawa, Hidetoshi; Fujii, Motoharu; Akaike, Gensuke; Uemura, Akihiro; Takahashi, Osamu; Niimi, Yasunari; Shinoda, Masaki

2014-01-01

Recent studies have shown that posterior circulation aneurysms, specifically posterior communicating artery (PCoA) aneurysms, are more likely to rupture than other aneurysms. To date, few studies have investigated the factors contributing to PCoA aneurysm rupture. The authors aimed to identify morphological and clinical characteristics predisposing to PCoA aneurysm rupture. The authors retrospectively reviewed 134 consecutive patients with PCoA aneurysms managed at their facility between July 2003 and December 2012. The authors divided patients into groups of those with aneurysmal rupture (n = 39) and without aneurysmal rupture (n = 95) and compared morphological and clinical characteristics. Morphological characteristics were mainly evaluated by 3D CT angiography and included diameter of arteries (anterior cerebral artery, middle cerebral artery, and internal carotid artery), size of the aneurysm, dome-to-neck ratio, neck direction of the aneurysmal dome around the PCoA (medial, lateral, superior, inferior, and posterior), aneurysm bleb formation, whether the PCoA was fetal type, and the existence of other intracranial unruptured aneurysm(s). Patients with ruptured PCoA aneurysms were significantly younger (a higher proportion were < 60 years of age) and a significantly higher proportion of patients with ruptured PCoA aneurysms showed a lateral direction of the aneurysmal dome around the PCoA, had bleb formation, and the aneurysm was > 7 mm in diameter and/or the dome-to-neck ratio was > 2.0. Multivariate logistic regression analysis showed age < 60 years (OR 4.3, p = 0.011), history of hypertension (OR 5.1, p = 0.008), lateral direction of the aneurysmal dome around the PCoA (OR 6.7, p = 0.0001), and bleb formation (OR 11, p < 0.0001) to be significantly associated with PCoA aneurysm rupture. The present results demonstrated that lateral projection of a PCoA aneurysm may be related to rupture.

The study of flow diversion effects on aneurysm using multiple enterprise stents and two flow diverters

PubMed Central

Kojima, Masahiro; Irie, Keiko; Fukuda, Toshio; Arai, Fumihito; Hirose, Yuichi; Negoro, Makoto

2012-01-01

Background: Computer-based simulation is necessary to clarify the hemodynamics in brain aneurysm. Specifically for endovascular treatments, the effects of indwelling intravascular devices on blood stream need to be considered. The most recent technology used for cerebral aneurysm treatment is related to the use of flow diverters to reduce the amount of flow entering the aneurysm. To verify the differences of flow reduction, we analyzed multiple Enterprise stents and two kinds of flow diverters. Materials and Methods: In this research, we virtually modeled three kinds of commercial intracranial stents (Enterprise, Silk, and Pipeline) and mounted to fit into the vessel wall, and deployed across the neck of an IC-ophthalmic artery aneurysm. Also, we compared the differences among multiple Enterprise stents and two flow diverters in a standalone mode. Results: From the numerical results, the values of wall shear stress and pressure are reduced in proportion to the size of mesh, especially in the inflow area. However, the reduced velocity within the aneurysm sac by the multiple stents is not as significant as the flow diverters. Conclusions: This is the first study analyzing the flow alterations among multiple Enterprise stents and flow diverters. The placement of small meshed stents dramatically reduced the aneurysmal fluid movement. However, compared to the flow diverters, we did not observe the reduction of flow velocity within the aneurysm by the multiple stents. PMID:23559981

Quantitative comparison of hemodynamics in simulated and 3D angiography models of cerebral aneurysms by use of computational fluid dynamics.

PubMed

Saho, Tatsunori; Onishi, Hideo

2015-07-01

In this study, we evaluated hemodynamics using simulated models and determined how cerebral aneurysms develop in simulated and patient-specific models based on medical images. Computational fluid dynamics (CFD) was analyzed by use of OpenFOAM software. Flow velocity, stream line, and wall shear stress (WSS) were evaluated in a simulated model aneurysm with known geometry and in a three-dimensional angiographic model. The ratio of WSS at the aneurysm compared with that at the basilar artery was 1:10 in simulated model aneurysms with a diameter of 10 mm and 1:18 in the angiographic model, indicating similar tendencies. Vortex flow occurred in both model aneurysms, and the WSS decreased in larger model aneurysms. The angiographic model provided accurate CFD information, and the tendencies of simulated and angiographic models were similar. These findings indicate that hemodynamic effects are involved in the development of aneurysms.

Closed-Cell Stent-Assisted Coiling of Intracranial Aneurysms: Evaluation of Changes in Vascular Geometry Using Digital Subtraction Angiography.

PubMed

Beller, Ebba; Klopp, David; Göttler, Jens; Kaesmacher, Johannes; Zimmer, Claus; Kirschke, Jan S; Prothmann, Sascha

2016-01-01

Stent-assisted coil embolization (SACE) plays an important role in the treatment of intracranial aneurysms. The purpose of this study was to investigate geometrical changes caused by closed-cell design stents in bifurcation and sidewall aneurysms. 31 patients with 34 aneurysms underwent SACE with closed-cell design stents. Inflow angle α, determined by aneurysm neck and afferent vessel, and angle between afferent and efferent vessel close to (δ1), respectively, more remote from the aneurysm neck (δ2) were graphically determined in 2D angiography projections. Stent assisted coiling resulted in a significant increase of all three angles from a mean value (±SEM) of α = 119° (±6.5°) pretreatment to 130° (±6.6°) posttreatment (P ≤ .001), δ1 = 129° (±6.4°) to 139° (±6.1°), (P ≤ .001) and δ2 = 115° (±8.4°) to 126° (±7.5°), (P ≤ .01). Angular change of δ1 in AcomA aneurysms was significant greater compared to sidewall aneurysms (26°±4.9° versus 8°± 2.3°, P ≤ .05). The initial angle of δ1 and δ2 revealed a significantly inverse relationship to the angle increase (δ1: r = -0.41, P ≤ .05 and δ2: r = -0.47, P ≤ .01). Moreover, angle δ1 was significantly higher in unruptured compared to ruptured aneurysms (135°±7.1° versus 103°±10.8°, P ≤ .05). Stent deployment modulates the geometry of the aneurysm-vessel complex, which may lead to favorable hemodynamic changes more similar to unruptured than to ruptured aneurysms. Our findings also suggest that the more acute-angled aneurysm-vessel anatomy, the larger the angular change. Further studies are needed to investigate whether these changes improve the clinical outcome.

Closed-Cell Stent-Assisted Coiling of Intracranial Aneurysms: Evaluation of Changes in Vascular Geometry Using Digital Subtraction Angiography

PubMed Central

Beller, Ebba; Klopp, David; Göttler, Jens; Kaesmacher, Johannes; Zimmer, Claus; Kirschke, Jan S.; Prothmann, Sascha

2016-01-01

Background Stent-assisted coil embolization (SACE) plays an important role in the treatment of intracranial aneurysms. The purpose of this study was to investigate geometrical changes caused by closed-cell design stents in bifurcation and sidewall aneurysms. Methods 31 patients with 34 aneurysms underwent SACE with closed-cell design stents. Inflow angle α, determined by aneurysm neck and afferent vessel, and angle between afferent and efferent vessel close to (δ1), respectively, more remote from the aneurysm neck (δ2) were graphically determined in 2D angiography projections. Results Stent assisted coiling resulted in a significant increase of all three angles from a mean value (±SEM) of α = 119° (±6.5°) pretreatment to 130° (±6.6°) posttreatment (P ≤ .001), δ1 = 129° (±6.4°) to 139° (±6.1°), (P ≤ .001) and δ2 = 115° (±8.4°) to 126° (±7.5°), (P ≤ .01). Angular change of δ1 in AcomA aneurysms was significant greater compared to sidewall aneurysms (26°±4.9° versus 8°± 2.3°, P ≤ .05). The initial angle of δ1 and δ2 revealed a significantly inverse relationship to the angle increase (δ1: r = -0.41, P ≤ .05 and δ2: r = -0.47, P ≤ .01). Moreover, angle δ1 was significantly higher in unruptured compared to ruptured aneurysms (135°±7.1° versus 103°±10.8°, P ≤ .05). Conclusion Stent deployment modulates the geometry of the aneurysm-vessel complex, which may lead to favorable hemodynamic changes more similar to unruptured than to ruptured aneurysms. Our findings also suggest that the more acute-angled aneurysm-vessel anatomy, the larger the angular change. Further studies are needed to investigate whether these changes improve the clinical outcome. PMID:27073908

Endovascular coil embolization of aneurysm neck for the treatment of ruptured intracranial aneurysm with bleb formation

PubMed Central

Wan, Jun; Gu, Weijin; Zhang, Xiaolong; Geng, Daoying; Lu, Gang; Huang, Lei; Zhang, Lei; Ge, Liang; Ji, Lihua

2014-01-01

Background Ruptured intracranial aneurysm (ICA) with bleb formation (RICABF) is a special type of ruptured ICA. However, the exact role and effectiveness of endovascular coil embolization (ECE) in RICABF is unknown. We aimed to investigate the effectiveness and safety of ECE of aneurysm neck for RICABF treatment. Material/Methods We retrospectively assessed consecutive patients who were hospitalized in our endovascular intervention center between October 2004 and May 2012. Overall, 86 patients underwent ECE of aneurysm neck for 86 RICABF. Treatments outcomes included secondary rupture/bleeding rate, aneurysm neck embolization rate, residual/recurrent aneurysm, intraoperative incidents, and post-embolization complications, as well as improvements in the Glasgow outcome scale (extended) (GOS-E). Results Complete occlusion was achieved in 72 aneurysms (72/86, 83.7%), while 12 aneurysms (12/86, 14.0%) had a residual neck, and 2 aneurysms (2/86, 2.3%) had a residual aneurysm. The postoperative GOS-E was 3 in 3 patients (3.5%), 4 in 10 patients (11.6%), and 5 in 73 patients (84.9%). Follow-up angiography was performed in all patients (mean 9.0 months, interquartile range of 9.0). Recurrence was found in 3 patients (3/86, 3.5%). No aneurysm rupture or bleeding was reported. Conclusions Our mid-term follow-up study showed that ECE of aneurysm neck was an effective and safe treatment modality for RICABF. The long-term effectiveness and safety of this interventional radiology technique need to be investigated in prospective and comparative studies. PMID:24986761

Intracranial aneurysms in patients with autosomal dominant polycystic kidney disease: prevalence, risk of rupture, and management. A systematic review.

PubMed

Cagnazzo, Federico; Gambacciani, Carlo; Morganti, Riccardo; Perrini, Paolo

2017-05-01

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disorder associated with high incidences of intracranial aneurysms. We performed a systematic review with the purpose of clarifying the prevalence, risk of rupture, and appropriate management of intracranial aneurysms in the ADPKD population. PRISMA guidelines were followed. We conducted a comprehensive literature search of three databases (PubMed, Ovid MEDLINE, and Ovid EMBASE) on all series reporting ADPKD patients with intracranial aneurysms. Our systematic review included 16 articles with a total of 563 patients with ADPKD and intracranial aneurysms. The prevalence of unruptured aneurysms was 11.5% (95% CI = 10.1-13%), whereas 1.9% (95% CI = 1.3-2.6%) of aneurysms were ruptured. Hypertension was present in 79.3% of patients with ADPKD and renal impairment in 65%. The mean size of ruptured aneurysms was slightly higher than unruptured (6 mm vs. 4.4 mm). The most common locations of unruptured and ruptured aneurysms were the ICA (40.5%) and MCA (45%), respectively. Asymptomatic patients studied with four-vessel angiography experienced 25% transient complications. Overall, 74% unruptured aneurysms were surgically treated with lower complication rates compared to endovascular treatment (11% vs. 27.7%). Among conservatively treated aneurysms, 2.9% ruptured at follow-up (rupture rate 0.4%/patient-year). Finally, the growth rate was 0.4% per patient-year, and the incidence of de novo aneurysm formation was 1.4% per patient-year. The prevalence of unruptured intracranial aneurysms in the ADPKD population is approximately 11%. Given the non-negligible rate of procedural complications, the management of these patients must be cautious and individualised. The rupture rate appears comparable to that of the general population. On the other hand, the 1.4% rate per patient-year of de novo aneurysms is non-negligible. These findings should be considered when counselling ADPKD patients regarding the appropriate management of intracranial aneurysms.

Biomechanical Simulation to Compare the Blood Hemodynamics and Cerebral Aneurysm Rupture Risk in Patients with Different Aneurysm Necks

NASA Astrophysics Data System (ADS)

Hajirayat, K.; Gholampour, S.; Sharifi, I.; Bizari, D.

2017-11-01

In this study, one normal subject and two patients suffering from a cerebral aneurysm with circular and elliptical necks are analyzed by using the fluid-structure interaction (FSI) method. Although the blood hemodynamics parameters increase after the occurrence of the disease, the largest increase is in the wall shear stress (by a factor of 4.1-6.5) as compared to the normal subject. The increase in these parameters for patients with a circular neck is more pronounced than that with an elliptical neck. The blood flow becomes slightly more turbulent after the occurrence of the cerebral aneurysm, though it still remains in the range of the laminar flow and the pulsatility of the blood flow in patients is 28-45% greater than that of the normal subject. Finally, the results show that the risk of vessel rupture in the cerebral aneurysm with a circular neck is 40.8% higher than that in the case of the cerebral aneurysm with an elliptical neck.

Analysis of saccular aneurysms in the Barrow Ruptured Aneurysm Trial.

PubMed

Spetzler, Robert F; Zabramski, Joseph M; McDougall, Cameron G; Albuquerque, Felipe C; Hills, Nancy K; Wallace, Robert C; Nakaji, Peter

2018-01-01

OBJECTIVE The Barrow Ruptured Aneurysm Trial (BRAT) is a prospective, randomized trial in which treatment with clipping was compared to treatment with coil embolization. Patients were randomized to treatment on presentation with any nontraumatic subarachnoid hemorrhage (SAH). Because all other randomized trials comparing these 2 types of treatments have been limited to saccular aneurysms, the authors analyzed the current BRAT data for this subgroup of lesions. METHODS The primary BRAT analysis included all sources of SAH: nonaneurysmal lesions; saccular, blister, fusiform, and dissecting aneurysms; and SAHs from an aneurysm associated with either an arteriovenous malformation or a fistula. In this post hoc review, the outcomes for the subgroup of patients with saccular aneurysms were further analyzed by type of treatment. The extent of aneurysm obliteration was adjudicated by an independent neuroradiologist not involved in treatment. RESULTS Of the 471 patients enrolled in the BRAT, 362 (77%) had an SAH from a saccular aneurysm. Patients with saccular aneurysms were assigned equally to the clipping and the coiling cohorts (181 each). In each cohort, 3 patients died before treatment and 178 were treated. Of the 178 clip-assigned patients with saccular aneurysms, 1 (1%) was crossed over to coiling, and 64 (36%) of the 178 coil-assigned patients were crossed over to clipping. There was no statistically significant difference in poor outcome (modified Rankin Scale score > 2) between these 2 treatment arms at any recorded time point during 6 years of follow-up. After the initial hospitalization, 1 of 241 (0.4%) clipped saccular aneurysms and 21 of 115 (18%) coiled saccular aneurysms required retreatment (p < 0.001). At the 6-year follow-up, 95% (95/100) of the clipped aneurysms were completely obliterated, compared with 40% (16/40) of the coiled aneurysms (p < 0.001). There was no difference in morbidity between the 2 treatment groups (p = 0.10). CONCLUSIONS In the subgroup of patients with saccular aneurysms enrolled in the BRAT, there was no significant difference between modified Rankin Scale outcomes at any follow-up time in patients with saccular aneurysms assigned to clipping compared with those assigned to coiling (intent-to-treat analysis). At the 6-year follow-up evaluation, rates of retreatment and complete aneurysm obliteration significantly favored patients who underwent clipping compared with those who underwent coiling. Clinical trial registration no.: NCT01593267 (clinicaltrials.gov).

Prevalence of Synchronous and Metachronous Aneurysms in Women With Abdominal Aortic Aneurysm.

PubMed

Wallinder, Jonas; Georgiou, Anna; Wanhainen, Anders; Björck, Martin

2018-06-20

Abdominal aortic aneurysm (AAA) is three to five times more common among men compared with women, yet up to 38% of all aneurysm related deaths affect women. The aim of this study was to estimate the prevalence of synchronous or metachronous aneurysms among women with AAA, as diagnosis and treatment could improve survival. This is a retrospective study of prospectively registered patients. All women operated on, or under surveillance for, AAA were identified at two Swedish hospitals. Aneurysms in different locations were identified using available imaging studies. Aneurysms were defined according to location: thoracic ascending aorta ≥42 mm, descending ≥33 mm, abdominal aorta ≥30 mm, common iliac artery ≥20 mm or 50% wider than the contralateral artery, common femoral artery ≥12 mm, popliteal artery ≥10 mm. A total of 339 women with an AAA were included. The median follow up was 2.8 (range 0-15.7) years. Thirty-one per cent had an aneurysm in the thoracic aorta (67 of 217 investigated, 84% were located in the descending aorta), 13 (19%) underwent repair. Twelve per cent had a common iliac artery aneurysm (24/259, 76% were investigated). Common femoral artery aneurysms were identified in 4.3% (8/184, 54% investigated). Popliteal artery aneurysms were identified in 4.0% (6/149, 44% investigated). The prevalence of infrainguinal aneurysms was higher among patients with synchronous iliac aneurysms (40% vs. 1.6%, OR 42, 95% CI 6.4-279, p < .001). Thoracic aortic aneurysms are common among women with AAA, most commonly affecting the descending aorta, and detection frequently results in repair. Popliteal and femoral aneurysms are not rare among women with AAA, and even common if there is a synchronous iliac aneurysm. Copyright © 2018 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.

Background differences in baseline and stimulated MMP levels influence abdominal aortic aneurysm susceptibility

PubMed Central

Dale, Matthew A.; Ruhlman, Melissa K.; Zhao, Shijia; Meisinger, Trevor; Gu, Linxia; Swier, Vicki J.; Agrawal, Devendra K.; Greiner, Timothy C.; Carson, Jeffrey S.; Baxter, B. Timothy; Xiong, Wanfen

2015-01-01

Objective Evidence has demonstrated profound influence of genetic background on cardiovascular phenotypes. Murine models in Marfan syndrome (MFS) have shown that genetic background-related variations affect thoracic aortic aneurysm formation, rupture, and lifespan of mice. MFS mice with C57Bl/6 genetic background are less susceptible to aneurysm formation compared to the 129/SvEv genetic background. In this study, we hypothesize that susceptibility to abdominal aortic aneurysm (AAA) will be increased in 129/SvEv mice versus C57Bl/6 mice. We tested this hypothesis by assessing differences in aneurysm size, tissue properties, immune response, and MMP expression. Methods Mice of C57Bl/6 or 129/SvEv background underwent AAA induction by periaortic application of CaCl2. Baseline aortic diameters, tissue properties and MMP levels were measured. After aneurysm induction, diameters, MMP expression, and immune response (macrophage infiltration and bone marrow transplantation) were measured. Results Aneurysms were larger in 129/SvEv mice than C57Bl/6 mice (83.0% ± 13.6 increase compared to 57.8% ± 6.4). The aorta was stiffer in the 129/SvEv mice compared to C57Bl/6 mice (952.5 kPa ± 93.6 versus 621.4 kPa ± 84.2). Baseline MMP-2 and post-aneurysm MMP-2 and -9 levels were higher in 129/SvEv aortas compared to C57Bl/6 aortas. Elastic lamella disruption/fragmentation and macrophage infiltration were increased in 129/SvEv mice. Myelogenous cell reversal by bone marrow transplantation did not affect aneurysm size. Conclusions These data demonstrate that 129/SvEv mice are more susceptible to AAA compared to C57Bl/6 mice. Intrinsic properties of the aorta between the two strains of mice, including baseline expression of MMP-2, influence susceptibility to AAA. PMID:26546710

Flow Diverters for Intracranial Aneurysms

PubMed Central

Alderazi, Yazan J.; Kass-Hout, Tareq; Prestigiacomo, Charles J.; Gandhi, Chirag D.

2014-01-01

Flow diverters (pipeline embolization device, Silk flow diverter, and Surpass flow diverter) have been developed to treat intracranial aneurysms. These endovascular devices are placed within the parent artery rather than the aneurysm sac. They take advantage of altering hemodynamics at the aneurysm/parent vessel interface, resulting in gradual thrombosis of the aneurysm occurring over time. Subsequent inflammatory response, healing, and endothelial growth shrink the aneurysm and reconstruct the parent artery lumen while preserving perforators and side branches in most cases. Flow diverters have already allowed treatment of previously untreatable wide neck and giant aneurysms. There are risks with flow diverters including in-stent thrombosis, perianeurysmal edema, distant and delayed hemorrhages, and perforator occlusions. Comparative efficacy and safety against other therapies are being studied in ongoing trials. Antiplatelet therapy is mandatory with flow diverters, which has highlighted the need for better evidence for monitoring and tailoring antiplatelet therapy. In this paper we review the devices, their uses, associated complications, evidence base, and ongoing studies. PMID:24967131

Intracranial aneurysmal pulsatility as a new individual criterion for rupture risk evaluation: biomechanical and numeric approach (IRRAs Project).

PubMed

Sanchez, M; Ecker, O; Ambard, D; Jourdan, F; Nicoud, F; Mendez, S; Lejeune, J-P; Thines, L; Dufour, H; Brunel, H; Machi, P; Lobotesis, K; Bonafe, A; Costalat, V

2014-09-01

The present study follows an experimental work based on the characterization of the biomechanical behavior of the aneurysmal wall and a numerical study where a significant difference in term of volume variation between ruptured and unruptured aneurysm was observed in a specific case. Our study was designed to highlight by means of numeric simulations the correlation between aneurysm sac pulsatility and the risk of rupture through the mechanical properties of the wall. In accordance with previous work suggesting a correlation between the risk of rupture and the material properties of cerebral aneurysms, 12 fluid-structure interaction computations were performed on 12 "patient-specific" cases, corresponding to typical shapes and locations of cerebral aneurysms. The variations of the aneurysmal volume during the cardiac cycle (ΔV) are compared by using wall material characteristics of either degraded or nondegraded tissues. Aneurysms were located on 6 different arteries: middle cerebral artery (4), anterior cerebral artery (3), internal carotid artery (1), vertebral artery (1), ophthalmic artery (1), and basilar artery (1). Aneurysms presented different shapes (uniform or multilobulated) and diastolic volumes (from 18 to 392 mm3). The pulsatility (ΔV/V) was significantly larger for a soft aneurysmal material (average of 26%) than for a stiff material (average of 4%). The difference between ΔV, for each condition, was statistically significant: P=.005. The difference in aneurysmal pulsatility as highlighted in this work might be a relevant patient-specific predictor of aneurysm risk of rupture. © 2014 by American Journal of Neuroradiology.

Hemodynamic Study of Flow Remodeling Stent Graft for the Treatment of Highly Angulated Abdominal Aortic Aneurysm

PubMed Central

Yeow, Siang Lin; Leo, Hwa Liang

2016-01-01

This study investigates the effect of a novel flow remodeling stent graft (FRSG) on the hemodynamic characteristics in highly angulated abdominal aortic aneurysm based on computational fluid dynamics (CFD) approach. An idealized aortic aneurysm with varying aortic neck angulations was constructed and CFD simulations were performed on nonstented models and stented models with FRSG. The influence of FRSG intervention on the hemodynamic performance is analyzed and compared in terms of flow patterns, wall shear stress (WSS), and pressure distribution in the aneurysm. The findings showed that aortic neck angulations significantly influence the velocity flow field in nonstented models, with larger angulations shifting the mainstream blood flow towards the center of the aorta. By introducing FRSG treatment into the aneurysm, erratic flow recirculation pattern in the aneurysm sac diminishes while the average velocity magnitude in the aneurysm sac was reduced in the range of 39% to 53%. FRSG intervention protects the aneurysm against the impacts of high velocity concentrated flow and decreases wall shear stress by more than 50%. The simulation results highlighted that FRSG may effectively treat aneurysm with high aortic neck angulations via the mechanism of promoting thrombus formation and subsequently led to the resorption of the aneurysm. PMID:27247612

Intradural Procedural Time to Assess Technical Difficulty of Superciliary Keyhole and Pterional Approaches for Unruptured Middle Cerebral Artery Aneurysms

PubMed Central

Choi, Yeon-Ju; Son, Wonsoo; Park, Ki-Su

2016-01-01

Objective This study used the intradural procedural time to assess the overall technical difficulty involved in surgically clipping an unruptured middle cerebral artery (MCA) aneurysm via a pterional or superciliary approach. The clinical and radiological variables affecting the intradural procedural time were investigated, and the intradural procedural time compared between a superciliary keyhole approach and a pterional approach. Methods During a 5.5-year period, patients with a single MCA aneurysm were enrolled in this retrospective study. The selection criteria for a superciliary keyhole approach included : 1) maximum diameter of the unruptured MCA aneurysm <15 mm, 2) neck diameter of the MCA aneurysm <10 mm, and 3) aneurysm location involving the sphenoidal or horizontal segment of MCA (M1) segment and MCA bifurcation, excluding aneurysms distal to the MCA genu. Meanwhile, the control comparison group included patients with the same selection criteria as for a superciliary approach, yet who preferred a pterional approach to avoid a postoperative facial wound or due to preoperative skin trouble in the supraorbital area. To determine the variables affecting the intradural procedural time, a multiple regression analysis was performed using such data as the patient age and gender, maximum aneurysm diameter, aneurysm neck diameter, and length of the pre-aneurysm M1 segment. In addition, the intradural procedural times were compared between the superciliary and pterional patient groups, along with the other variables. Results A total of 160 patients underwent a superciliary (n=124) or pterional (n=36) approach for an unruptured MCA aneurysm. In the multiple regression analysis, an increase in the diameter of the aneurysm neck (p<0.001) was identified as a statistically significant factor increasing the intradural procedural time. A Pearson correlation analysis also showed a positive correlation (r=0.340) between the neck diameter and the intradural procedural time. When comparing the superciliary and pterional groups, no statistically significant between-group difference was found in terms of the intradural procedural time reflecting the technical difficulty (mean±standard deviation : 29.8±13.0 min versus 27.7±9.6 min). Conclusion A superciliary keyhole approach can be a useful alternative to a pterional approach for an unruptured MCA aneurysm with a maximum diameter <15 mm and neck diameter <10 mm, representing no more of a technical challenge. For both surgical approaches, the technical difficulty increases along with the neck diameter of the MCA aneurysm. PMID:27847568

Aneurysm Characteristics Associated with the Rupture Risk of Intracranial Aneurysms: A Self-Controlled Study.

PubMed

Kang, Huibin; Ji, Wenjun; Qian, Zenghui; Li, Youxiang; Jiang, Chuhan; Wu, Zhongxue; Wen, Xiaolong; Xu, Wenjuan; Liu, Aihua

2015-01-01

This study analyzed the rupture risk of intracranial aneurysms (IAs) according to aneurysm characteristics by comparing the differences between two aneurysms in different locations within the same patient. We utilized this self-controlled model to exclude potential interference from all demographic factors to study the risk factors related to IA rupture. A total of 103 patients were diagnosed with IAs between January 2011 and April 2015 and were enrolled in this study. All enrolled patients had two IAs. One IA (the case) was ruptured, and the other (the control) was unruptured. Aneurysm characteristics, including the presence of a daughter sac, the aneurysm neck, the parent artery diameter, the maximum aneurysm height, the maximum aneurysm width, the location, the aspect ratio (AR, maximum perpendicular height/average neck diameter), the size ratio (SR, maximum aneurysm height/average parent diameter) and the width/height ratio (WH ratio, maximum aneurysm width/maximum aneurysm height), were collected and analyzed to evaluate the rupture risks of the two IAs within each patient and to identify the independent risk factors associated with IA rupture. Multivariate, conditional, backward, stepwise logistic regression analysis was performed to identify the independent risk factors associated with IA rupture. The multivariate analysis identified the presence of a daughter sac (odds ratio [OR], 13.80; 95% confidence interval [CI], 1.65-115.87), a maximum aneurysm height ≥7 mm (OR, 4.80; 95% CI, 1.21-18.98), location on the posterior communicating artery (PCOM) or anterior communicating artery (ACOM; OR, 3.09; 95% CI, 1.34-7.11) and SR (OR, 2.13; 95% CI, 1.16-3.91) as factors that were significantly associated with IA rupture. The presence of a daughter sac, the maximum aneurysm height, PCOM or ACOM locations and SR (>1.5±0.7) of unruptured IAs were significantly associated with IA rupture.

Intraluminal cell transplantation prevents growth and rupture in a model of rupture-prone saccular aneurysms.

PubMed

Marbacher, Serge; Frösén, Juhana; Marjamaa, Johan; Anisimov, Andrey; Honkanen, Petri; von Gunten, Michael; Abo-Ramadan, Usama; Hernesniemi, Juha; Niemelä, Mika

2014-12-01

Aneurysm occlusion by intraluminal thrombus formation is the desired effect of all endovascular treatments. Intraluminal thrombus may, however, recanalize and be absorbed, unless it is infiltrated by cells that turn it into fibrous tissue (neointima). Because ruptured aneurysm walls are characterized by loss of smooth muscle cells, we assessed the impact of mural cell loss on wall remodeling of thrombosed aneurysms and investigated whether neointima formation could be enhanced by direct transplantation of cells into the thrombus. Sidewall aneurysms were microsurgically created in rats (n=81). Certain aneurysms were decellularized. Thrombosis was induced using direct injection of a fibrin polymer into the aneurysm. CM-Dil-labeled smooth muscle cells were injected into 25 of 46 fibrin embolized aneurysms. Recanalization and aneurysm growth were monitored with magnetic resonance angiography. Endoscopy, optical projection tomography, histology, and immunohistochemistry were used to study the fate of transplanted cells, thrombus organization, and neointima formation. Decellularized embolized aneurysms demonstrated higher angiographic recurrence compared with decellularized embolized aneurysms with transplanted cells (P=0.037). Local cell replacement at the time of thrombosis resulted in better histological neointima formation than both nondecellularized embolized aneurysms (P<0.001) and decellularized embolized aneurysms (P=0.002). Aneurysm growth and rupture were observed exclusively in decellularized embolized aneurysms. Lack of smooth muscle cells in the aneurysm wall promotes wall degradation, aneurysm growth and rupture, even if the aneurysm is occluded by luminal thrombus. Transplantation of smooth muscle cells into the luminal thrombus can reduce this degenerative remodeling. © 2014 American Heart Association, Inc.

Morphological and Hemodynamic Discriminators for Rupture Status in Posterior Communicating Artery Aneurysms

PubMed Central

Karmonik, Christof; Fang, Yibin; Xu, Jinyu; Yu, Ying; Cao, Wei; Liu, Jianmin; Huang, Qinghai

2016-01-01

Background and Purpose The conflicting findings of previous morphological and hemodynamic studies on intracranial aneurysm rupture may be caused by the relatively small sample sizes and the variation in location of the patient-specific aneurysm models. We aimed to determine the discriminators for aneurysm rupture status by focusing on only posterior communicating artery (PCoA) aneurysms. Materials and Methods In 129 PCoA aneurysms (85 ruptured, 44 unruptured), clinical, morphological and hemodynamic characteristics were compared between the ruptured and unruptured cases. Multivariate logistic regression analysis was performed to determine the discriminators for rupture status of PCoA aneurysms. Results While univariate analyses showed that the size of aneurysm dome, aspect ratio (AR), size ratio (SR), dome-to-neck ratio (DN), inflow angle (IA), normalized wall shear stress (NWSS) and percentage of low wall shear stress area (LSA) were significantly associated with PCoA aneurysm rupture status. With multivariate analyses, significance was only retained for higher IA (OR = 1.539, p < 0.001) and LSA (OR = 1.393, p = 0.041). Conclusions Hemodynamics and morphology were related to rupture status of intracranial aneurysms. Higher IA and LSA were identified as discriminators for rupture status of PCoA aneurysms. PMID:26910518

Morphological and Hemodynamic Discriminators for Rupture Status in Posterior Communicating Artery Aneurysms.

PubMed

Lv, Nan; Wang, Chi; Karmonik, Christof; Fang, Yibin; Xu, Jinyu; Yu, Ying; Cao, Wei; Liu, Jianmin; Huang, Qinghai

2016-01-01

The conflicting findings of previous morphological and hemodynamic studies on intracranial aneurysm rupture may be caused by the relatively small sample sizes and the variation in location of the patient-specific aneurysm models. We aimed to determine the discriminators for aneurysm rupture status by focusing on only posterior communicating artery (PCoA) aneurysms. In 129 PCoA aneurysms (85 ruptured, 44 unruptured), clinical, morphological and hemodynamic characteristics were compared between the ruptured and unruptured cases. Multivariate logistic regression analysis was performed to determine the discriminators for rupture status of PCoA aneurysms. While univariate analyses showed that the size of aneurysm dome, aspect ratio (AR), size ratio (SR), dome-to-neck ratio (DN), inflow angle (IA), normalized wall shear stress (NWSS) and percentage of low wall shear stress area (LSA) were significantly associated with PCoA aneurysm rupture status. With multivariate analyses, significance was only retained for higher IA (OR = 1.539, p < 0.001) and LSA (OR = 1.393, p = 0.041). Hemodynamics and morphology were related to rupture status of intracranial aneurysms. Higher IA and LSA were identified as discriminators for rupture status of PCoA aneurysms.

225 intracranial aneurysms treated with the Low-profile Visualized Intraluminal Support (LVIS) stent: a single-center retrospective study.

PubMed

Su, Wei; Zhang, Yisen; Chen, Junfan; Liu, Jian; Rajah, Gary; Yang, Xinjian

2018-04-23

Background For the treatment of intracranial aneurysms, the low-profile visualized intraluminal support (LVIS) stent is a new generation of highly visible-braided stent that was recently introduced in China. Here, we report our single-center retrospective experience of safety and efficacy utilizing LVIS for stent-assisted coiling of intracranial aneurysms. Methods We included 218 patients with intracranial aneurysms consecutively treated with LVIS SR stents at our center in this study. Postoperative and follow-up embolization scores, procedural complications, clinical and angiographic findings at mid-term follow-up, as well as recurrence rate, preoperative and follow-up mRS scores were analyzed. Results Two hundred and eighteen patients with two hundred and twenty five intracranial aneurysms were enrolled. The locations and distribution were ICA (125, 55.6%), PcomA (47, 20.9%), VA (38, 16.8%), and BA (15, 6.7%). Two hundred and eighteen aneurysms were treated with the stent-assisted coiling and seven patients with LVIS stents alone. Angiographic follow-up was available for 115 (51.1%) aneurysms, 8 (7.0%) of which had recurrences including 7 (6.5%) unruptured aneurysms and 1(14.3%) ruptured aneurysm. The procedural complication rate was 2.75% in total, including distal hemorrhage (1, 0.45%; SAH), ischemic events (5, 2.3%). Conclusions Our single-center retrospective experience is one of the larger studies to date assessing the LVIS device. Compared with many laser-cut stent studies, the LVIS device had a higher aneurysm complete occlusion rate at follow-up coupled with low complication rates. However, this study was our initial experience with LVIS, larger patient numbers, and longer follow-up will be needed to fully assess the long-term efficacy of LVIS in treating intracranial aneurysms.

Enhanced caspase activity contributes to aortic wall remodeling and early aneurysm development in a murine model of Marfan syndrome.

PubMed

Emrich, Fabian C; Okamura, Homare; Dalal, Alex R; Penov, Kiril; Merk, Denis R; Raaz, Uwe; Hennigs, Jan K; Chin, Jocelyn T; Miller, Miquell O; Pedroza, Albert J; Craig, Juliana K; Koyano, Tiffany K; Blankenberg, Francis G; Connolly, Andrew J; Mohr, Friedrich W; Alvira, Cristina M; Rabinovitch, Marlene; Fischbein, Michael P

2015-01-01

Rupture and dissection of aortic root aneurysms remain the leading causes of death in patients with the Marfan syndrome, a hereditary connective tissue disorder that affects 1 in 5000 individuals worldwide. In the present study, we use a Marfan mouse model (Fbn1(C1039G/+)) to investigate the biological importance of apoptosis during aneurysm development in Marfan syndrome. Using in vivo single-photon emission computed tomographic-imaging and ex vivo autoradiography for Tc99m-annexin, we discovered increased apoptosis in the Fbn1(C1039G/+) ascending aorta during early aneurysm development peaking at 4 weeks. Immunofluorescence colocalization studies identified smooth muscle cells (SMCs) as the apoptotic cell population. As biological proof of concept that early aortic wall apoptosis plays a role in aneurysm development in Marfan syndrome, Fbn1(C1039G/+) mice were treated daily from 2 to 6 weeks with either (1) a pan-caspase inhibitor, Q-VD-OPh (20 mg/kg), or (2) vehicle control intraperitoneally. Q-VD-OPh treatment led to a significant reduction in aneurysm size and decreased extracellular matrix degradation in the aortic wall compared with control mice. In vitro studies using Fbn1(C1039G/+) ascending SMCs showed that apoptotic SMCs have increased elastolytic potential compared with viable cells, mostly because of caspase activity. Moreover, in vitro (1) cell membrane isolation, (2) immunofluorescence staining, and (3) scanning electron microscopy studies illustrate that caspases are expressed on the exterior cell surface of apoptotic SMCs. Caspase inhibition attenuates aneurysm development in an Fbn1(C1039G/+) Marfan mouse model. Mechanistically, during apoptosis, caspases are expressed on the cell surface of SMCs and likely contribute to elastin degradation and aneurysm development in Marfan syndrome. © 2014 American Heart Association, Inc.

Unruptured intracranial aneurysms in the Familial Intracranial Aneurysm and International Study of Unruptured Intracranial Aneurysms cohorts: differences in multiplicity and location.

PubMed

Mackey, Jason; Brown, Robert D; Moomaw, Charles J; Sauerbeck, Laura; Hornung, Richard; Gandhi, Dheeraj; Woo, Daniel; Kleindorfer, Dawn; Flaherty, Matthew L; Meissner, Irene; Anderson, Craig; Connolly, E Sander; Rouleau, Guy; Kallmes, David F; Torner, James; Huston, John; Broderick, Joseph P

2012-07-01

Familial predisposition is a recognized nonmodifiable risk factor for the formation and rupture of intracranial aneurysms (IAs). However, data regarding the characteristics of familial IAs are limited. The authors sought to describe familial IAs more fully, and to compare their characteristics with a large cohort of nonfamilial IAs. The Familial Intracranial Aneurysm (FIA) study is a multicenter international study with the goal of identifying genetic and other risk factors for formation and rupture of IAs in a highly enriched population. The authors compared the FIA study cohort with the International Study of Unruptured Intracranial Aneurysms (ISUIA) cohort with regard to patient demographic data, IA location, and IA multiplicity. To improve comparability, all patients in the ISUIA who had a family history of IAs or subarachnoid hemorrhage were excluded, as well as all patients in both cohorts who had a ruptured IA prior to study entry. Of 983 patients enrolled in the FIA study with definite or probable IAs, 511 met the inclusion criteria for this analysis. Of the 4059 patients in the ISUIA study, 983 had a previous IA rupture and 657 of the remainder had a positive family history, leaving 2419 individuals in the analysis. Multiplicity was more common in the FIA patients (35.6% vs 27.9%, p<0.001). The FIA patients had a higher proportion of IAs located in the middle cerebral artery (28.6% vs 24.9%), whereas ISUIA patients had a higher proportion of posterior communicating artery IAs (13.7% vs 8.2%, p=0.016). Heritable structural vulnerability may account for differences in IA multiplicity and location. Important investigations into the underlying genetic mechanisms of IA formation are ongoing.

The clinical spectrum of unruptured intracranial aneurysms.

PubMed

Raps, E C; Rogers, J D; Galetta, S L; Solomon, R A; Lennihan, L; Klebanoff, L M; Fink, M E

1993-03-01

A retrospective study was performed to delineate the clinical characteristics of symptomatic unruptured aneurysms. Patient histories, operative reports, and angiograms in 111 patients with 132 unruptured aneurysms were reviewed. Tertiary care university hospital. One hundred eleven patients with 132 unruptured intracranial aneurysms were studied. There were 85 women and 26 men, with a mean age of 51.2 years (age range, 11 to 77 years). Many patients were referred by community neurologists and neurosurgeons for further evaluation and neurosurgical management. Fifty-four symptomatic patients were identified. Group 1 (n = 19; mean aneurysm diameter, 2.1 cm) had acute symptoms: ischemia (n = 7), headache (n = 7), seizure (n = 3), and cranial neuropathy (n = 2). Group 2 (n = 35; mean aneurysm diameter, 2.2 cm) had chronic symptoms attributed to mass effect: headache (n = 18), visual loss (n = 10), pyramidal tract dysfunction (n = 4), and facial pain (n = 3). Group 3 (n = 57; mean aneurysm diameter, 1.1 cm) had asymptomatic aneurysms. Acute severe headache, comparable to subarachnoid hemorrhage headache, but without nuchal rigidity, was associated with the following mechanisms: aneurysm thrombosis, localized meningeal inflammation, and unexplained. Unruptured aneurysms may be misdiagnosed as optic neuritis or migraine, or serve as a nidus for cerebral thromboembolic events. Internal carotid artery and posterior circulation aneurysms were more likely to cause focal symptoms from mass effect than were anterior cerebral artery and middle cerebral artery aneurysms. Weeks to years may elapse before their diagnosis. The absence of subarachnoid blood does not exclude an aneurysm as a cause for acute or chronic neurologic symptoms.

Aneurysm-Specific miR-221 and miR-146a Participates in Human Thoracic and Abdominal Aortic Aneurysms

PubMed Central

Venkatesh, Premakumari; Phillippi, Julie; Chukkapalli, Sasanka; Rivera-Kweh, Mercedes; Velsko, Irina; Gleason, Thomas; VanRyzin, Paul; Aalaei-Andabili, Seyed Hossein; Ghanta, Ravi Kiran; Beaver, Thomas; Chan, Edward Kar Leung; Kesavalu, Lakshmyya

2017-01-01

Altered microRNA expression is implicated in cardiovascular diseases. Our objective was to determine microRNA signatures in thoracic aortic aneurysms (TAAs) and abdominal aortic aneurysms (AAAs) compared with control non-aneurysmal aortic specimens. We evaluated the expression of fifteen selected microRNA in human TAA and AAA operative specimens compared to controls. We observed significant upregulation of miR-221 and downregulation of miR-1 and -133 in TAA specimens. In contrast, upregulation of miR-146a and downregulation of miR-145 and -331-3p were found only for AAA specimens. Upregulation of miR-126 and -486-5p and downregulation of miR-30c-2*, -155, and -204 were observed in specimens of TAAs and AAAs. The data reveal microRNA expression signatures unique to aneurysm location and common to both thoracic and abdominal pathologies. Thus, changes in miR-1, -29a, -133a, and -221 are involved in TAAs and miR-145, -146, and -331-3p impact AAAs. This work validates prior studies on microRNA expression in aneurysmal diseases. PMID:28425970

Aneurysm-Specific miR-221 and miR-146a Participates in Human Thoracic and Abdominal Aortic Aneurysms.

PubMed

Venkatesh, Premakumari; Phillippi, Julie; Chukkapalli, Sasanka; Rivera-Kweh, Mercedes; Velsko, Irina; Gleason, Thomas; VanRyzin, Paul; Aalaei-Andabili, Seyed Hossein; Ghanta, Ravi Kiran; Beaver, Thomas; Chan, Edward Kar Leung; Kesavalu, Lakshmyya

2017-04-20

Altered microRNA expression is implicated in cardiovascular diseases. Our objective was to determine microRNA signatures in thoracic aortic aneurysms (TAAs) and abdominal aortic aneurysms (AAAs) compared with control non-aneurysmal aortic specimens. We evaluated the expression of fifteen selected microRNA in human TAA and AAA operative specimens compared to controls. We observed significant upregulation of miR-221 and downregulation of miR-1 and -133 in TAA specimens. In contrast, upregulation of miR-146a and downregulation of miR-145 and -331-3p were found only for AAA specimens. Upregulation of miR-126 and -486-5p and downregulation of miR-30c-2*, -155, and -204 were observed in specimens of TAAs and AAAs. The data reveal microRNA expression signatures unique to aneurysm location and common to both thoracic and abdominal pathologies. Thus, changes in miR-1, -29a, -133a, and -221 are involved in TAAs and miR-145, -146, and -331-3p impact AAAs. This work validates prior studies on microRNA expression in aneurysmal diseases.

The Effect of Hemodynamics on Cerebral Aneurysm Morphology

NASA Astrophysics Data System (ADS)

Metcalfe, Ralph; Mantha, Aishwarya; Karmonik, Christof; Strother, Charles

2004-11-01

One of the difficulties in applying principles of hemodynamics to the study of blood flow in aneurysms are the drastic variations in possible shape of both the aneurysms and the parent arteries in the region of interest. We have taken data from three para-opthalmic internal carotid artery aneurysms using 3D-digital subtraction angiography (3D-DSA) and performed CFD simulations of steady and unsteady flows through the three different cases using the same pressure gradients and pulsatile flow waveforms (based on the Ku model for flow through the Carotid bifurcation). We have found that the total pressure differential within the aneurysms is consistent with the direction of flow, and that the dynamic pressure gradient within the aneurysm is very small compared with the static pressure variations. Wall shear stresses were highest near regions of sharp arterial curvature, but always remained low inside the aneurysm. These results suggest a more complex role for hemodynamics in aneurysm generation, growth and rupture.

Angiographic and clinical outcomes of balloon remodeling versus unassisted coil embolization in the ruptured aneurysm cohort of the GEL THE NEC study.

PubMed

Dabus, Guilherme; Brinjikji, Waleed; Amar, Arun P; Delgado Almandoz, Josser E; Diaz, Orlando M; Jabbour, Pascal; Hanel, Ricardo; Hui, Ferdinand; Kelly, Michael; Layton, Kennith F; Miller, Jeffrey W; Levy, Elad I; Moran, Christopher J; Suh, Dae Chul; Woo, Henry; Sellar, Robbin; Hoh, Brian; Evans, Avery; Kallmes, David F

2018-05-01

GEL THE NEC (GTN) was a multicenter prospective registry developed to assess the safety and efficacy of HydroSoft coils in treating intracranial aneurysms. We compared the angiographic and clinical outcomes of aneurysms treated with balloon assisted coil embolization (BACE) versus unassisted coil embolization (CE) in the ruptured aneurysm cohort. GTN was performed at 27 centers in five countries. Patients aged 21-90 years with a ruptured aneurysm 3-15 mm in size were eligible for enrollment. We analyzed demographics/comorbidities, aneurysm location, and geometry, including maximum diameter, neck size, and dome to neck ratio, immediate and long term angiographic outcomes (graded by an independent core laboratory using the modified Raymond Scale), and procedure related adverse events. Angiographic and clinical outcomes were studied using χ 2 and t tests. Of the 599 patients in the GTN, 194 met the inclusion criteria. 84 were treated with BACE and 110 with CE. There were more prior smokers in the BACE group (p=0.01). The BACE group also had more vertebrobasilar aneurysms (p=0.006) and a larger mean neck size (p=0.02). More aneurysms were immediately completely occluded in the BACE group (p=0.02) Procedure- related major morbidity and mortality were no different between the techniques (p=0.4 and p=1, respectively). In this prospective ruptured aneurysm cohort from the GTN, BACE resulted in greater occlusion rates compared with unassisted CE with similar morbi-mortality. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A new low-profile visualized intraluminal support (LVIS) device, LVIS Blue: laboratory comparison between old and new LVIS.

PubMed

Chung, Joonho; Matsuda, Yoshikazu; Nelson, Jessica; Keigher, Kiffon; Lopes, Demetrius K

2018-01-01

Objectives The Low-profile Visualized Intraluminal Support (LVIS) device is a flexible intracranial stent. The first generation of this system had significant challenges in consistently providing good wall apposition and aneurysm neck coverage. A new modified LVIS, LVIS Blue (Blue), has been developed to address these issues. The purpose of this study is to report a laboratory comparison of wall apposition and aneurysm neck coverage between the original LVIS and Blue. Methods In bench-top experiments, we noted the visual appearance of the devices and evaluated changes in stent cell angles, neck coverage surface area (%), and stent cell crossing profile for microcatheters using a fusiform aneurysm model. Our in vitro experiments included evaluation of wall apposition and aneurysm neck coverage of the devices under direct radiographic visualization. Results Blue showed three definite different zones (a mid-zone, a high-density zone, and a transitional zone) and higher metal coverage in the straight fusiform aneurysm model compared to LVIS. Two commercially available microcatheters easily crossed the stent cell at the greater curvature for both devices. In in vitro experiments, Blue showed better wall apposition in tortuous arteries and achieved higher neck coverage in the bifurcation aneurysm compared to LVIS. Discussion Blue achieved better wall apposition in tortuous arteries and higher aneurysm neck coverage (higher metal-to-artery ratio) in bifurcation aneurysms than LVIS. Our results may provide informative physical properties of LVIS and Blue to be expected when those are used for stent-assisted coil embolization of a large-giant fusiform aneurysm or a bifurcation saccular aneurysm clinically.

Unraveling the relationship between arterial flow and intra-aneurysmal hemodynamics.

PubMed

Morales, Hernán G; Bonnefous, Odile

2015-02-26

Arterial flow rate affects intra-aneurysmal hemodynamics but it is not clear how their relationship is. This uncertainty hinders the comparison among studies, including clinical evaluations, like a pre- and post-treatment status, since arterial flow rates may differ at each time acquisition. The purposes of this work are as follows: (1) To study how intra-aneurysmal hemodynamics changes within the full physiological range of arterial flow rates. (2) To provide characteristic curves of intra-aneurysmal velocity, wall shear stress (WSS) and pressure as functions of the arterial flow rate. Fifteen image-based aneurysm models were studied using computational fluid dynamics (CFD) simulations. The full range of physiological arterial flow rates reported in the literature was covered by 11 pulsatile simulations. For each aneurysm, the spatiotemporal-averaged blood flow velocity, WSS and pressure were calculated. Spatiotemporal-averaged velocity inside the aneurysm linearly increases as a function of the mean arterial flow (minimum R(2)>0.963). Spatiotemporal-averaged WSS and pressure at the aneurysm wall can be represented by quadratic functions of the arterial flow rate (minimum R(2)>0.996). Quantitative characterizations of spatiotemporal-averaged velocity, WSS and pressure inside cerebral aneurysms can be obtained with respect to the arterial flow rate. These characteristic curves provide more information of the relationship between arterial flow and aneurysm hemodynamics since the full range of arterial flow rates is considered. Having these curves, it is possible to compare experimental studies and clinical evaluations when different flow conditions are used. Copyright © 2015 Elsevier Ltd. All rights reserved.

Blood flow in intracranial aneurysms treated with Pipeline embolization devices: computational simulation and verification with Doppler ultrasonography on phantom models

PubMed Central

2015-01-01

Purpose: The aim of this study was to validate a computational fluid dynamics (CFD) simulation of flow-diverter treatment through Doppler ultrasonography measurements in patient-specific models of intracranial bifurcation and side-wall aneurysms. Methods: Computational and physical models of patient-specific bifurcation and sidewall aneurysms were constructed from computed tomography angiography with use of stereolithography, a three-dimensional printing technology. Flow dynamics parameters before and after flow-diverter treatment were measured with pulse-wave and color Doppler ultrasonography, and then compared with CFD simulations. Results: CFD simulations showed drastic flow reduction after flow-diverter treatment in both aneurysms. The mean volume flow rate decreased by 90% and 85% for the bifurcation aneurysm and the side-wall aneurysm, respectively. Velocity contour plots from computer simulations before and after flow diversion closely resembled the patterns obtained by color Doppler ultrasonography. Conclusion: The CFD estimation of flow reduction in aneurysms treated with a flow-diverting stent was verified by Doppler ultrasonography in patient-specific phantom models of bifurcation and side-wall aneurysms. The combination of CFD and ultrasonography may constitute a feasible and reliable technique in studying the treatment of intracranial aneurysms with flow-diverting stents. PMID:25754367

Evaluation of the levels of metalloproteinsase-2 in patients with abdominal aneurysm and abdominal hernias.

PubMed

Antoszewska, Magdalena

2013-05-01

Abdominal aortic aneurysms and abdominal hernias become an important health problems of our times. Abdominal aortic aneurysm and its rupture is one of the most dangerous fact in vascular surgery. There are some theories pointing to a multifactoral genesis of these kinds of diseases, all of them assume the attenuation of abdominal fascia and abdominal aortic wall. The density and continuity of these structures depend on collagen and elastic fibers structure. Reducing the strength of the fibers may be due to changes in the extracellular matrix (ECM) by the proteolytic enzymes-matrix metalloproteinases (MMPs) that degrade extracellular matrix proteins. These enzymes play an important role in the development of many disease: malignant tumors (colon, breast, lung, pancreas), cardiovascular disease (myocardial infarction, ischemia-reperfusion injury), connective tissue diseases (Ehler-Danlos Syndrome, Marfan's Syndrome), complications of diabetes (retinopathy, nephropathy). One of the most important is matrix metalloproteinase-2 (MMP-2). The aim of the study was an estimation of the MMP-2 blood levels in patients with abdominal aortic aneurysm and primary abdominal hernia, and in patients with only abdominal aortic aneurysm. The study involved 88 patients aged 42 to 89 years, including 75 men and 13 women. Patients were divided into two groups: patients with abdominal aortic aneurysm and primary abdominal hernia (45 persons, representing 51.1% of all group) and patients with only abdominal aortic aneurysm (43 persons, representing 48,9% of all group). It was a statistically significant increase in MMP-2 blood levels in patients with abdominal aortic aneurysm and primary abdominal hernia compared to patients with only abdominal aortic aneurysm. It was a statistically significant increase in the prevalence of POCHP in patients with only abdominal aortic aneurysm compared to patients with abdominal aortic aneurysm and primary abdominal hernia. Statistically significant higher MMP-2 blood levels in patients with abdominal aortic aneurysm and primary abdominal hernia seems shows that this enzyme plays a role in the pathogenesis of primary abdominal hernias. The observed distribution of MMP-2 blood levels in patients with abdominal aortic aneurysm and primary abdominal hernia may raise the conclusion that this enzyme determines the presence of multi-organ failure of the connective tissue--the patients with only abdominal aortic aneurysm had significantly lower MMP-2 blood levels.

Different treatment modalities of fusiform basilar trunk aneurysm: study on computational hemodynamics.

PubMed

Wu, Chen; Xu, Bai-Nan; Sun, Zheng-Hui; Wang, Fu-Yu; Liu, Lei; Zhang, Xiao-Jun; Zhou, Ding-Biao

2012-01-01

Unclippable fusiform basilar trunk aneurysm is a formidable condition for surgical treatment. The aim of this study was to establish a computational model and to investigate the hemodynamic characteristics in a fusiform basilar trunk aneurysm. The three-dimensional digital model of a fusiform basilar trunk aneurysm was constructed using MIMICS, ANSYS and CFX software. Different hemodynamic modalities and border conditions were assigned to the model. Thirty points were selected randomly on the wall and within the aneurysm. Wall total pressure (WTP), wall shear stress (WSS), and blood flow velocity of each point were calculated and hemodynamic status was compared between different modalities. The quantitative average values of the 30 points on the wall and within the aneurysm were obtained by computational calculation point by point. The velocity and WSS in modalities A and B were different from those of the remaining 5 modalities; and the WTP in modalities A, E and F were higher than those of the remaining 4 modalities. The digital model of a fusiform basilar artery aneurysm is feasible and reliable. This model could provide some important information to clinical treatment options.

Computational Study of Intracranial Aneurysms with Flow Diverting Stent: Correlation with Surgical Outcome

NASA Astrophysics Data System (ADS)

Tang, Yik Sau; Chiu, Tin Lok; Tsang, Anderson Chun On; Leung, Gilberto Ka Kit; Chow, Kwok Wing

2016-11-01

Intracranial aneurysm, abnormal swelling of the cerebral artery, can cause massive internal bleeding in the subarachnoid space upon aneurysm rupture, leading to a high mortality rate. Deployment of a flow diverting stent through endovascular technique can obstruct the blood flow into the aneurysm, thus reducing the risk of rupture. Patient-specific models with both bifurcation and sidewall aneurysms have been investigated. Computational fluid dynamics analysis with physiological boundary conditions has been performed. Several hemodynamic parameters including volume flow rate into the aneurysm and the energy (sum of the fluid kinetic and potential energy) loss between the inlet and outlets were analyzed and compared with the surgical outcome. Based on the simulation results, we conjecture that a clinically successful case might imply less blood flow into the aneurysm after stenting, and thus a smaller amount of energy loss in driving the fluid flow in that portion of artery. This study might provide physicians with quantitative information for surgical decision making. (Partial financial support by the Innovation and Technology Support Program (ITS/011/13 & ITS/150/15) of the Hong Kong Special Administrative Region Government)

Predictors and outcomes of endoleaks in the Veterans Affairs Open Versus Endovascular Repair (OVER) Trial of Abdominal Aortic Aneurysms.

PubMed

Lal, Brajesh K; Zhou, Wei; Li, Ziyi; Kyriakides, Tassos; Matsumura, Jon; Lederle, Frank A; Freischlag, Julie

2015-12-01

The Veterans Affairs Open Versus Endovascular Repair (OVER) Trial of Abdominal Aortic Aneurysms study was a randomized controlled trial comparing open vs endovascular repair (EVAR) in standard-risk patients with infrarenal aortic aneurysms. The analysis reported here identifies characteristics, risk factors, and long-term outcome of endoleaks in patients treated with EVAR in the OVER cohort. The OVER trial enrolled 881 patients, of whom 439 received successful EVAR. Logistic regression analysis was used to identify predictors for endoleaks and secondary interventions. Kaplan-Meier survival analysis, longitudinal plots, and generalized linear mixed models methods were used to describe time to endoleak detection, resolution, or death. During a mean follow-up of 6.2 ± 2.4 years, 135 patients (30.5%) developed 187 endoleaks. Four patients with EVAR went on to rupture; these four patients did not all have an endoleak. Mortality between patients who did and did not develop endoleaks was not significantly different. The 187 endoleaks included 12% type I, 76% type II, 3% type III, 3% type IV, and 6% indeterminate. Patient demographics and vascular risk factors were not associated with endoleak development. The presence of endoleaks resulted in an increase in aneurysm diameter over time (P < .0001). Fifty-three percent of endoleaks resolved spontaneously, and 31.9% received secondary interventions. The initial aneurysm size independently predicted a need for secondary interventions (P < .0003). Delayed type II endoleaks (detected >1 year after EVAR) were associated with aneurysm enlargement compared with the early counterpart. There was no difference in aneurysm size or length of survival between type II and other types of endoleak. We present one of the most comprehensive and longest follow-up analyses of patients treated with aortic endografts. Endoleaks were common and negatively affected aneurysm diameter reduction. Delayed type II endoleaks were associated with late aneurysm diameter enlargement. Endoleaks and aneurysm diameter enlargement were not associated with excess mortality compared with those without these features. Published by Elsevier Inc.

Hemodynamic response during aneurysm clipping surgery among experienced neurosurgeons.

PubMed

Bunevicius, Adomas; Bilskiene, Diana; Macas, Andrius; Tamasauskas, Arimantas

2016-02-01

Neurosurgery is a challenging field associated with high levels of mental stress. The goal of this study was to investigate the hemodynamic response of experienced neurosurgeons during aneurysm clipping surgery and to evaluate whether neurosurgeons' hemodynamic responses are associated with patients' clinical statuses. Four vascular neurosurgeons (all male; mean age 51 ± 10 years; post-residency experience ≥7 years) were studied during 42 aneurysm clipping procedures. Blood pressure (BP) and heart rate (HR) were assessed at rest and during seven phases of surgery: before the skin incision, after craniotomy, after dural opening, after aneurysm neck dissection, after aneurysm clipping, after dural closure and after skin closure. HR and BP were significantly greater during surgery relative to the rest situation (p ≤ 0.03). There was a statistically significant increase in neurosurgeons' HR (F [6, 41] = 10.88, p < 0.001), systolic BP (F [6, 41] = 2.97, p = 0.01), diastolic BP (F [6, 41] = 2.49, p = 0.02) and mean BP (F [6, 41] = 3.36, p = 0.003) during surgery. The greatest mean HR was after aneurysm clipping, and the greatest BP was after aneurysm neck dissection. Systolic, diastolic and mean BPs were significantly greater during surgical clipping for unruptured aneurysms compared to ruptured aneurysms across all stages of surgery (p ≤ 0.002); however, after adjusting for neurosurgeon experience, the difference in BP as a function of aneurysm rupture was not significant (p > 0.08). Aneurysm location, intraoperative aneurysm rupture, admission WFNS score, admission Glasgow Coma Scale scores and Fisher grade were not associated with neurosurgeons' intraoperative HR and BP (all p > 0.07). Aneurysm clipping surgery is associated with significant hemodynamic system activation among experienced neurosurgeons. The greatest HR and BP were after aneurysm neck dissection and clipping. Aneurysm location and patient clinical status were not associated with intraoperative changes of neurosurgeons' HR and BP.

Local Delivery Is Critical for Monocyte Chemotactic Protein-1 Mediated Site-Specific Murine Aneurysm Healing.

PubMed

Hourani, Siham; Motwani, Kartik; Wajima, Daisuke; Fazal, Hanain; Jones, Chad H; Doré, Sylvain; Hosaka, Koji; Hoh, Brian L

2018-01-01

Local delivery of monocyte chemotactic protein-1 (MCP-1/CCL2) via our drug-eluting coil has been shown to promote intrasaccular aneurysm healing via an inflammatory pathway. In this study, we validate the importance of local MCP-1 in murine aneurysm healing. Whether systemic, rather than local, delivery of MCP-1 can direct site-specific aneurysm healing has significant translational implications. If systemic MCP-1 is effective, then MCP-1 could be administered as a pill rather than by endovascular procedure. Furthermore, we confirm that MCP-1 is the primary effector in our MCP-1 eluting coil-mediated murine aneurysm healing model. We compare aneurysm healing with repeated intraperitoneal MCP-1 versus vehicle injection, in animals with control poly(lactic-co-glycolic) acid (PLGA)-coated coils. We demonstrate elimination of the MCP-1-associated tissue-healing response by knockout of MCP-1 or CCR2 (MCP-1 receptor) and by selectively inhibiting MCP-1 or CCR2. Using immunofluorescent probing, we explore the cell populations found in healed aneurysm tissue following each intervention. Systemically administered MCP-1 with PLGA coil control does not produce comparable aneurysm healing, as seen with MCP-1 eluting coils. MCP-1-directed aneurysm healing is eliminated by selective inhibition of MCP-1 or CCR2 and in MCP-1-deficient or CCR2-deficient mice. No difference was detected in M2 macrophage and myofibroblast/smooth muscle cell staining with systemic MCP-1 versus vehicle in aneurysm wall, but a significant increase in these cell types was observed with MCP-1 eluting coil implant and attenuated by MCP-1/CCR2 blockade or deficiency. We show that systemic MCP-1 concurrent with PLGA-coated platinum coil implant is not sufficient to produce site-specific aneurysm healing. MCP-1 is a critical, not merely complementary, actor in the aneurysm healing pathway.

Atrial Septal Aneurysm and Patent Foramen Ovale as Risk Factors for Cryptogenic Stroke in Patients Less Than 55 Years of Age: A Study using Transesophageal Echocardiography

NASA Technical Reports Server (NTRS)

Cabanes, L.; Mas, J. L.; Cohen, A.; Amarenco, P.; Cabanes, P. A.; Oubary, P.; Chedru, F.; Guerin, F.; Bousser, M. G.; deRecondo, J.

1993-01-01

Background and Purpose: An association between atrial septal aneurysm and embolic events has been suggested. Atrial septal aneurysm has been shown to be associated with patent foramen ovale and,.in some reports, with mitral valve prolapse. These two latter cardiac disorder; have been identified as potential risk factors for ischemic stroke. The aim of this prospective study was to assess the role of atrial septal aneurysm as an independent risk factor for stroke, especially for cryptogenic stroke. Methods: We studied the prevalence of atrial septal aneurysm, patent foramen ovale, and mitral valve prolapse in 100 consecutive patients <55 years of age with ischemic stroke who underwent extensive etiological investigations. We compared these results with those in a control group of 50 consecutive patients. The diagnosis of atrial septal aneurysm and patent foramen ovale relied on transesophageal echocardiography with a contrast study and that of mitral valve prolapse, on two-dimensional transthoracic echocardiography. Results: Stepwise logistic regression analysis showed that atrial septal aneurysm (odds ratio, 4.3; 95% confidence interval, 1.3 to 14.6; P=.01) and patent foramen ovale (odds ratio, 3.9; 95% confidence interval, 1.5 to 10; P=.003) but not mitral valve prolapse were significantly associated with the diagnosis of cryptogenic stroke. The stroke odds of a patient with both atrial septal aneurysm and patent foramen ovale were 33.3 times (95% confidence interval, 4.1 to 270) the stroke odds of a patient with neither of these cardiac disorders. For a patient with atrial septal aneurysm of >lo-mm excursion, the stroke odds were approximately 8 times the stroke odds of a patient with atrial septal aneurysm of <10 mm. Conclusions: This study shows that atrial septal aneurysm and patent foramen ovale are both significantly associated with cryptogenic stroke and that their association has a marked synergistic effect. Atrial septal aneurysms of >lo-mm excursion are associated with a higher risk of stroke. (Stroke. 1993;24:1865-1873.) KEY WORDS aneurysm echocardiography foramen ovale, patent mitral valve prolapse o young adults

Relationship between Angiographic Results and Morphology in Sidewall Intracranial Aneurysms after Stent-Assisted Coil Embolization.

PubMed

Nii, Kouhei; Aikawa, Hiroshi; Tsutsumi, Masanori; Eto, Ayumu; Iko, Minoru; Sakamoto, Kimiya; Inoue, Ritsuro; Mitsutake, Takafumi; Hanada, Hayatsura; Kazekawa, Kiyoshi

2016-03-01

Stent-assisted coil embolization (SACE) is used to address wide-necked or complex aneurysms. However, as they may recanalize after SACE, predictors of recanalization are needed. We investigated the relationship between follow-up angiographic results and the morphology of sidewall (SW) aneurysms in patients treated by SACE. Between September 2010 and September 2014, we performed 80 SACE procedures for SW intracranial aneurysms. Angiographic findings, obtained immediately after the procedure, 3-6 months thereafter, and when aneurysmal recanalization was suspected on MR angiogram scan, were recorded. Morphologically, the SW aneurysms were classified as "outside" (OS) and "partially inside" (PI) based on the curve of the axes of the proximal or distal parent artery with respect to the aneurysmal neck. Follow-up angiographic studies on OS- and PI SW aneurysms were compared. On the initial angiograms, we classified 42 aneurysms as OS and 38 as PI. Immediately after SACE, there was no significant difference in the angiographic findings on OS and PI aneurysms. However, on follow-up angiograms, there was a significant difference in the rate of spontaneous improvement (4 of 42 [OS] versus 21 of 38 [PI], P = .001). We performed additional coil embolization to treat 3 recanalized OS aneurysms. SW aneurysms classified morphologically as PI tended to occlude progressively even after incomplete occlusion by SACE. In contrast, aneurysms classified as OS must be observed carefully after SACE. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Delayed Vasospasm after Aneurysmal Subarachnoid Hemorrhage in Behcet Syndrome.

PubMed

Kim, Jun Hak; Lee, Si-Un; Huh, Choonwoong; Oh, Chang Wan; Bang, Jae Seung; Kim, Tackeun

2016-03-01

A man visited the emergency room with a headache. Brain computed tomography showed aneurysmal subarachnoid hemorrhage (SAH) and multiple aneurysms. After aneurysm clipping surgery, the patient was discharged. After 5 days, he was admitted to the hospital with skin ulceration and was diagnosed with Behcet syndrome. An angiogram taken 7 weeks after aneurysmal SAH showed intracranial vasospasm. Because inflammation in Behcet syndrome may aggravate intracranial vasospasm, intracranial vasospasm after aneurysmal SAH in Behcet syndrome should be monitored for longer compared to general aneurysmal SAH.

Delayed Vasospasm after Aneurysmal Subarachnoid Hemorrhage in Behcet Syndrome

PubMed Central

Kim, Jun Hak; Lee, Si-Un; Huh, Choonwoong; Oh, Chang Wan; Bang, Jae Seung

2016-01-01

A man visited the emergency room with a headache. Brain computed tomography showed aneurysmal subarachnoid hemorrhage (SAH) and multiple aneurysms. After aneurysm clipping surgery, the patient was discharged. After 5 days, he was admitted to the hospital with skin ulceration and was diagnosed with Behcet syndrome. An angiogram taken 7 weeks after aneurysmal SAH showed intracranial vasospasm. Because inflammation in Behcet syndrome may aggravate intracranial vasospasm, intracranial vasospasm after aneurysmal SAH in Behcet syndrome should be monitored for longer compared to general aneurysmal SAH. PMID:27114963

Long-term angiographic outcome of stent-assisted coiling compared to non-assisted coiling of intracranial saccular aneurysms

PubMed Central

Ozretić, David; Radoš, Marko; Pavliša, Goran; Poljaković, Zdravka

2015-01-01

Aim To compare angiographic result at long-term follow-up, and rates of progressive occlusion, recurrence, and retreatment of stent-assisted coiled (SAC) and non-assisted coiled (NAC) intracranial saccular aneurysms. Methods Retrospective evaluation of department records identified 260 patients with 283 saccular intracranial aneurysms who had long-term angiographic follow-up (more than 12 months) and were successfully treated with SAC (89 aneurysms) or NAC (194 aneurysms) at the University Hospital Center Zagreb from June 2005 to July 2012. Initial and control angiographic results in both groups were graded using Roy/Raymond scale, converted to descriptive terms, and the differences between them were evaluated for statistical significance. A multivariate analysis was performed to identify factors related to progression of aneurysm occlusion and recurrence at follow-up, and those related to aneurysm retreatment. Results There were more progressively occluded aneurysms in SAC group (38 of 89 aneurysms, 42.7%) than in NAC group (46 of 194, 23.7%) (P = 0.002), but there were no significant differences in the rates of recanalization, regrowth, and stable result. Multivariate logistic regression identified the use of stent as the most important factor associated with progressive occlusion (P = 0.015, odds ratio 2.22, 95% confidence interval 1.17-4.21), and large aneurysm size and posterior circulation location as most predictive of aneurysm recurrence and retreatment. Conclusion The use of stent is associated with delayed occlusion of initially incompletely coiled aneurysms during follow-up, but does not reduce the rate of recurrence and retreatment compared to coiling alone. Long-term angiographic follow-up is needed for both SAC and NAC aneurysms. PMID:25727039

[Use of an iliac branched endoprostheis in endovascular treatment for an abdominal aortic aneurysm combined with aneurysms of both common iliac arteries].

PubMed

Imaev, T E; Kuchin, I V; Lepilin, P M; Kolegaev, A S; Medvedeva, I S; Komlev, A E; Akchurin, R S

An abdominal aortic aneurysm appears to be combined with aneurysmatic lesions of the common iliac arteries in 30-40% of cases. Like abdominal aortic aneurysms, aneurysms of the common iliac arteries rarely manifest themselves clinically. The lethality rate in case of rupture is comparable to that for rupture of an abdominal aortic aneurysm. During endoprosthetic repair of abdominal aortic aneurysms combined with aneurysms of the common iliac arteries, in order to prevent endoleaks and to improve the distal zone of fixation of endografts surgeons often resort to embolization of internal iliac arteries, which may lead to ischaemic postoperative complications. One of the methods of preserving pelvic blood flow is the use of an iliac branched endograft. A series of studies evaluating long-term outcomes demonstrated that this method proved to be both safe and effective, and with the suitable anatomy is a method of choice in high surgical risk patients. The present article deals with a clinical case report concerning bilateral endoprosthetic repair of the common iliac arteries, combined with endoprosthetic repair of an abdominal aortic aneurysm, with the description of technical peculiarities of implanting an iliac branched graft.

Rupture of a non-traumatic anterior communicating artery aneurysm: Does location of aneurysm associate with functional independence following post-acute in-patient neurorehabilitation?

PubMed

Stabel, Henriette Holm; Pedersen, Asger Roer; Johnsen, Søren Paaske; Nielsen, Jørgen Feldbæk

2017-12-01

Patients with non-traumatic rupture of an aneurysm located at the anterior communicating artery (ACoA) often experience cognitive disabilities. It is unknown whether location of aneurysm also affects the possibility for improvement in functional independence compared to patients with an aneurysmal subarachnoid hemorrhage (a-SAH) located elsewhere. The aim was to explore the association between location of aneurysm (ACoA versus other) and level of functional independence, measured by Functional Independence Measure (FIM), at discharge from rehabilitation. Additionally, age and FIM at admission were explored. Historical cohort study among 107 patients with a-SAH based on data from a clinical database and a population-based register. Data were analyzed using multivariable logistic regression. Patients with ACoA were admitted with poorer cognitive FIM (median 6 (IQR 5-14) compared to patients with aneurysms located elsewhere (median 12 (IQR 6-23) (p = 0.0129); no difference at discharge. No association between aneurysm location and functional independence was observed. Higher age was associated with poorer outcome in bowel management OR 0.54 (95% CI 0.31-0.92), bladder management OR 0.59 (95% CI 0.35-0.98), comprehension OR 0.53 (95% CI 0.30-0.94), and memory OR 0.48 (95% CI 0.25-0.93). Overall, FIM at admission was associated with functional independence at discharge with the exception of stair walking and bladder management which did not reach statistical significance. ACoA was not associated with poorer level of functional independence compared to patients with a-SAH located elsewhere. Higher age was associated with poorer outcome in continence, comprehension, and memory, whereas higher FIM was associated with better functional independence across items at discharge.

Wall stress on ascending thoracic aortic aneurysms with bicuspid compared with tricuspid aortic valve.

PubMed

Xuan, Yue; Wang, Zhongjie; Liu, Raymond; Haraldsson, Henrik; Hope, Michael D; Saloner, David A; Guccione, Julius M; Ge, Liang; Tseng, Elaine

2018-03-08

Guidelines for repair of bicuspid aortic valve-associated ascending thoracic aortic aneurysms have been changing, most recently to the same criteria as tricuspid aortic valve-ascending thoracic aortic aneurysms. Rupture/dissection occurs when wall stress exceeds wall strength. Recent studies suggest similar strength of bicuspid aortic valve versus tricuspid aortic valve-ascending thoracic aortic aneurysms; thus, comparative wall stress may better predict dissection in bicuspid aortic valve versus tricuspid aortic valve-ascending thoracic aortic aneurysms. Our aim was to determine whether bicuspid aortic valve-ascending thoracic aortic aneurysms had higher wall stresses than their tricuspid aortic valve counterparts. Patients with bicuspid aortic valve- and tricuspid aortic valve-ascending thoracic aortic aneurysms (bicuspid aortic valve = 17, tricuspid aortic valve = 19) greater than 4.5 cm underwent electrocardiogram-gated computed tomography angiography. Patient-specific 3-dimensional geometry was reconstructed and loaded to systemic pressure after accounting for prestress geometry. Finite element analyses were performed using the LS-DYNA solver (LSTC Inc, Livermore, Calif) with user-defined fiber-embedded material model to determine ascending thoracic aortic aneurysm wall stress. Bicuspid aortic valve-ascending thoracic aortic aneurysms 99th-percentile longitudinal stresses were 280 kPa versus 242 kPa (P = .028) for tricuspid aortic valve-ascending thoracic aortic aneurysms in systole. These stresses did not correlate to diameter for bicuspid aortic valve-ascending thoracic aortic aneurysms (r = -0.004) but had better correlation to tricuspid aortic valve-ascending thoracic aortic aneurysms diameter (r = 0.677). Longitudinal stresses on sinotubular junction were significantly higher in bicuspid aortic valve-ascending thoracic aortic aneurysms than in tricuspid aortic valve-ascending thoracic aortic aneurysms (405 vs 329 kPa, P = .023). Bicuspid aortic valve-ascending thoracic aortic aneurysm 99th-percentile circumferential stresses were 548 kPa versus 462 kPa (P = .033) for tricuspid aortic valve-ascending thoracic aortic aneurysms, which also did not correlate to bicuspid aortic valve-ascending thoracic aortic aneurysm diameter (r = 0.007). Circumferential and longitudinal stresses were greater in bicuspid aortic valve- than tricuspid aortic valve-ascending thoracic aortic aneurysms and were more pronounced in the sinotubular junction. Peak wall stress did not correlate with bicuspid aortic valve-ascending thoracic aortic aneurysm diameter, suggesting diameter alone in this population may be a poor predictor of dissection risk. Our results highlight the need for patient-specific aneurysm wall stress analysis for accurate dissection risk prediction. Copyright © 2018 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Clipping Versus Coiling in the Management of Posterior Communicating Artery Aneurysms with Third Nerve Palsy: A Systematic Review and Meta-Analysis.

PubMed

Gaberel, Thomas; Borha, Alin; di Palma, Camille; Emery, Evelyne

2016-03-01

To compare surgical clipping with endovascular coiling in terms of recovery from oculomotor nerve palsy (ONP) in the management of posterior communicating artery (PCoA) aneurysms causing third nerve palsy. We conducted a systematic review of the literature and meta-analysis. The meta-analysis included 11 relevant studies involving 384 patients with third nerve palsy caused by PCoA aneurysms at baseline, of whom 257 (67.0%) were treated by clipping and 127 were treated by coiling (33.0%). Pooled odds ratios of the impact of clipping or coiling on complete ONP recovery, lack of ONP recovery, and procedure-related death were calculated. The overall complete ONP recovery rate was 42.5% in the coiling group compared with 83.6% in the clipping group. The increase in complete ONP recovery in the clipping group corresponds to an overall pooled Mantel-Haenszel odds ratio of 4.44 (95% confidence interval = 1.66-11.84). Subgroup analysis revealed a clear benefit of clipping over coiling in patients with ruptured aneurysms, but not in patients with unruptured aneurysms. No procedure-related deaths were reported by any of the 11 studies. Surgical clipping of PCoA aneurysms causing third nerve palsy achieves better ONP recovery than endovascular coiling; this could be particularly true in the case of ruptured aneurysms. In view of the purely observational data, statements about this effect should be made with great caution. A randomized trial would better address the therapeutic dilemma, but pending the results of such a trial, we recommend treating PCoA aneurysms causing ONP with surgery. Copyright © 2016 Elsevier Inc. All rights reserved.

Differential expression levels of collagen 1A2, tissue inhibitor of metalloproteinase 4, and cathepsin B in intracranial aneurysms.

PubMed

Babu, R Arun; Paul, Pradip; Purushottam, Meera; Srinivas, Dwarakanath; Somanna, Sampath; Jain, Sanjeev

2016-01-01

Intracranial aneurysms (IAs) express a variety of differentially expressed genes when compared to the normal artery. The aim of this study was to evaluate the expression level of a few genes in the aneurysm wall and to correlate them with various clinicoradiological factors. The mRNA level of collagen 1A2 (COL1A2), tissue inhibitor of metalloproteinase 4 (TIMP4), and cathepsin B (CTSB) genes were studied in 23 aneurysmal walls and 19 superficial temporal arteries harvested from 23 patients undergoing clipping of IAs, by real-time polymerase chain reaction method. The mean fold change of COL1A2 gene between the aneurysm sample and the superficial temporal artery (STA) sample was 2.46 ± 0.12, that of TIMP4 gene was 0.31 ± 0, and that of CTSB gene was 31.47 ± 39.01. There was a positive correlation of TIMP4 expression level with maximum diameter of aneurysm (P = 0.008) and fundus of aneurysm (P = 0.012). The mean fold change of CTSB of patients who had preoperative hydrocephalus in the computed tomogram (CT) scan of the head at admission was 56.16 and that of the patients who did not have hydrocephalus was 13.51 (P = 0.008). The mean fold change of CTSB of patients who developed fresh postoperative deficits or worsening of the preexisting deficits was 23.64 and that of the patients who did not develop was 42.22 (P = 0.039). COL1A2 gene and CTSB genes were overexpressed, and TIMP4 gene was underexpressed in the aneurysmal sac compared to STA and their expression levels were associated with a few clinicoradiological factors.

3D digital subtraction angiography of intracranial aneurysms: comparison of flat panel detector with conventional image intensifier TV system using a vascular phantom.

PubMed

Kakeda, S; Korogi, Y; Ohnari, N; Hatakeyama, Y; Moriya, J; Oda, N; Nishino, K; Miyamoto, W

2007-05-01

Compared with the image intensifier (I.I.)-TV system, the flat panel detector (FPD) system of direct conversion type has several theoretic advantages, such as higher spatial resolution, wide dynamic range, and no image distortion. The purpose of this study was to compare the image quality of 3D digital subtraction angiography (DSA) in the FPD and conventional I.I.-TV systems using a vascular phantom. An anthropomorphic vascular phantom was designed to simulate the various intracranial aneurysms with aneurysmal bleb. The tubes of this vascular phantom were filled with 2 concentrations of contrast material (300 and 150 mg I/mL), and we obtained 3D DSA using the FPD and I.I.-TV systems. First, 2 blinded radiologists compared the volume-rendering images for 3D DSA on the FPD and I.I.-TV systems, looking for pseudostenosis artifacts. Then, 2 other radiologists independently evaluated both systems for the depiction of the simulated aneurysm and aneurysmal bleb using a 5-point scale. For the degree of the pseudostenosis artifacts at the M1 segment of the middle cerebral artery at 300 mg I/mL, 3D DSA with FPD system showed mild stenoses, whereas severe stenoses were observed at 3D DSA with I.I.-TV system. At both concentrations, the FPD system was significantly superior to I.I.-TV system regarding the depiction of aneurysm and aneurysmal bleb. Compared with the I.I.-TV system, the FPD system could create high-resolution 3D DSA combined with a reduction of the pseudostenosis artifacts.

Variability of hemodynamic parameters using the common viscosity assumption in a computational fluid dynamics analysis of intracranial aneurysms.

PubMed

Suzuki, Takashi; Takao, Hiroyuki; Suzuki, Takamasa; Suzuki, Tomoaki; Masuda, Shunsuke; Dahmani, Chihebeddine; Watanabe, Mitsuyoshi; Mamori, Hiroya; Ishibashi, Toshihiro; Yamamoto, Hideki; Yamamoto, Makoto; Murayama, Yuichi

2017-01-01

In most simulations of intracranial aneurysm hemodynamics, blood is assumed to be a Newtonian fluid. However, it is a non-Newtonian fluid, and its viscosity profile differs among individuals. Therefore, the common viscosity assumption may not be valid for all patients. This study aims to test the suitability of the common viscosity assumption. Blood viscosity datasets were obtained from two healthy volunteers. Three simulations were performed for three different-sized aneurysms, two using measured value-based non-Newtonian models and one using a Newtonian model. The parameters proposed to predict an aneurysmal rupture obtained using the non-Newtonian models were compared with those obtained using the Newtonian model. The largest difference (25%) in the normalized wall shear stress (NWSS) was observed in the smallest aneurysm. Comparing the difference ratio to the NWSS with the Newtonian model between the two Non-Newtonian models, the difference of the ratio was 17.3%. Irrespective of the aneurysmal size, computational fluid dynamics simulations with either the common Newtonian or non-Newtonian viscosity assumption could lead to values different from those of the patient-specific viscosity model for hemodynamic parameters such as NWSS.

Improved microsurgical creation of venous pouch arterial bifurcation aneurysms in rabbits.

PubMed

Sherif, C; Marbacher, S; Erhardt, S; Fandino, J

2011-01-01

The choice of the experimental aneurysm model is essential for valid embolization-device evaluations. So far, the use of the rabbit venous pouch arterial bifurcation aneurysm model has been limited by demanding microsurgery, low aneurysm patency rates, and high mortality. This study aimed to facilitate microsurgery and to reduce mortality by optimized peri-/postoperative management. Aneurysms were created in 16 New Zealand white rabbits under general intravenous anesthesia. Using modified microsurgical techniques, we sutured a jugular vein pouch into a bifurcation created between both CCAs. Aggressive anticoagulation (intraoperative intravenous: 1000-IU heparin, 10-mg acetylsalicylic acid/kg; postoperative subcutaneous: 14 days, 250-IU/kg /day heparin) and prolonged postoperative anesthesia (fentanyl patches: 12.5 μg/h for 72 hours) were applied. Angiographic characteristics of created experimental aneurysms were assessed. The reduced number of interrupted sutures and aggressive anticoagulation caused no intra-/postoperative bleeding, resulting in 0% mortality. Four weeks postoperation, angiography showed patency in 14 of 16 aneurysms (87.5%) and Ohshima type B bifurcation geometry. Mean values of parent-artery diameters (2.3 mm), aneurysm lengths (7.9 mm), and neck widths (4.1 mm) resulted in a mean 1.9 aspect ratio. Compared with historical controls, the use of modified microsurgical techniques, aggressive anticoagulation, and anesthesia resulted in higher aneurysm patency rates and lower mortality rates in the venous pouch arterial bifurcation aneurysm model. Gross morphologic features of these aneurysms were similar to those of most human intracranial aneurysms.

Is fetal-type posterior cerebral artery a risk factor for intracranial aneurysm as analyzed by multislice CT angiography?

PubMed

He, Zhen; Wan, Yeda

2018-01-01

Fetal-type posterior cerebral artery (FTP) is a common anatomic variation that is closely associated with intracranial aneurysm. In the present study, multislice computed tomography angiography (CTA) was performed to assess whether FTP is a risk factor for intracranial aneurysm. CTA data of 364 consecutive cases of patients who were suspected with cerebrovascular disease or intracranial aneurysm of intracranial artery from 2013 to 2016 were reviewed and the incidence rates of FTP, other variations of the circle of Willis, intracranial aneurysm and FTP with intracranial aneurysm were evaluated. The χ 2 test was used to assess the influence of FTP and gender on the incidence rates of other variations of the circle of Willis, intracranial aneurysm and internal carotid artery-posterior communicating artery (ICA-PComA) aneurysm. Binary logistic regression analysis was performed to assess the associations of FTP and gender with intracranial aneurysm and ICA-PComA aneurysm. Compared with non-FTP patients, FTP cases exhibited significantly higher rates of other variations of the circle of Willis (χ 2 =80.173, P<0.001) and ICA-PComA aneurysm (χ 2 =4.437, P=0.035). Among patients with FTP and bilateral FTP, more female than male patients with intracranial aneurysm were identified. However, among all patients with intracranial aneurysm, no statistically significant differences in the prevalence of FTP (χ 2 =2.577, P=0.108) and bilateral FTP (χ 2 =2.199, P=0.159) between males and females were identified. Binary logistic regression analysis revealed that FTP and gender were risk factors for intracranial aneurysm and ICA-PComA aneurysm. A moderate association between FTP and ICA-PComA aneurysm (OR=2.762) were identified, although there was a weak association between FTP and intracranial aneurysm [odds ratio (OR)=1.365]. Furthermore, a strong association was identified between gender and intracranial aneurysm (OR=0.328), and a moderate association existed between gender and ICA-PComA aneurysm (OR=0.357). In conclusion, female gender is an independent risk factor for intracranial aneurysm, and FTP and female gender are independent risk factors for ICA-PComA aneurysm.

Is fetal-type posterior cerebral artery a risk factor for intracranial aneurysm as analyzed by multislice CT angiography?

PubMed Central

He, Zhen; Wan, Yeda

2018-01-01

Fetal-type posterior cerebral artery (FTP) is a common anatomic variation that is closely associated with intracranial aneurysm. In the present study, multislice computed tomography angiography (CTA) was performed to assess whether FTP is a risk factor for intracranial aneurysm. CTA data of 364 consecutive cases of patients who were suspected with cerebrovascular disease or intracranial aneurysm of intracranial artery from 2013 to 2016 were reviewed and the incidence rates of FTP, other variations of the circle of Willis, intracranial aneurysm and FTP with intracranial aneurysm were evaluated. The χ2 test was used to assess the influence of FTP and gender on the incidence rates of other variations of the circle of Willis, intracranial aneurysm and internal carotid artery-posterior communicating artery (ICA-PComA) aneurysm. Binary logistic regression analysis was performed to assess the associations of FTP and gender with intracranial aneurysm and ICA-PComA aneurysm. Compared with non-FTP patients, FTP cases exhibited significantly higher rates of other variations of the circle of Willis (χ2=80.173, P<0.001) and ICA-PComA aneurysm (χ2=4.437, P=0.035). Among patients with FTP and bilateral FTP, more female than male patients with intracranial aneurysm were identified. However, among all patients with intracranial aneurysm, no statistically significant differences in the prevalence of FTP (χ2=2.577, P=0.108) and bilateral FTP (χ2=2.199, P=0.159) between males and females were identified. Binary logistic regression analysis revealed that FTP and gender were risk factors for intracranial aneurysm and ICA-PComA aneurysm. A moderate association between FTP and ICA-PComA aneurysm (OR=2.762) were identified, although there was a weak association between FTP and intracranial aneurysm [odds ratio (OR)=1.365]. Furthermore, a strong association was identified between gender and intracranial aneurysm (OR=0.328), and a moderate association existed between gender and ICA-PComA aneurysm (OR=0.357). In conclusion, female gender is an independent risk factor for intracranial aneurysm, and FTP and female gender are independent risk factors for ICA-PComA aneurysm. PMID:29434687

The relative risk of aortic aneurysm in patients with giant cell arteritis compared with the general population of the UK.

PubMed

Robson, Joanna C; Kiran, Amit; Maskell, Joe; Hutchings, Andrew; Arden, Nigel; Dasgupta, Bhaskar; Hamilton, William; Emin, Akan; Culliford, David; Luqmani, Raashid A

2015-01-01

To evaluate the risk of aortic aneurysm in patients with giant cell arteritis (GCA) compared with age-, gender- and location-matched controls. A UK General Practice Research Database (GPRD) parallel cohort study of 6999 patients with GCA and 41 994 controls, matched on location, age and gender, was carried out. A competing risk model using aortic aneurysm as the primary outcome and non-aortic-aneurysm-related death as the competing risk was used to determine the relative risk (subhazard ratio) between non-GCA and GCA subjects, after adjustment for cardiovascular risk factors. Comparing the GCA cohort with the non-GCA cohort, the adjusted subhazard ratio (95% CI) for aortic aneurysm was 1.92 (1.52 to 2.41). Significant predictors of aortic aneurysm were being an ex-smoker (2.64 (2.03 to 3.43)) or a current smoker (3.37 (2.61 to 4.37)), previously taking antihypertensive drugs (1.57 (1.23 to 2.01)) and a history of diabetes (0.32 (0.19 to 0.56)) or cardiovascular disease (1.98 (1.50 to 2.63)). In a multivariate model of the GCA cohort, male gender (2.10 (1.38 to 3.19)), ex-smoker (2.20 (1.22 to 3.98)), current smoker (3.79 (2.20 to 6.53)), previous antihypertensive drugs (1.62 (1.00 to 2.61)) and diabetes (0.19 (0.05 to 0.77)) were significant predictors of aortic aneurysm. Patients with GCA have a twofold increased risk of aortic aneurysm, and this should be considered within the range of other risk factors including male gender, age and smoking. A separate screening programme is not indicated. The protective effect of diabetes in the development of aortic aneurysms in patients with GCA is also demonstrated. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The influence of atmospheric pressure on aortic aneurysm rupture--is the diameter of the aneurysm important?

PubMed

Urbanek, Tomasz; Juśko, Maciej; Niewiem, Alfred; Kuczmik, Wacław; Ziaja, Damian; Ziaja, Krzysztof

2015-01-01

The rate of aortic aneurysm rupture correlates with the aneurysm's diameter, and a higher rate of rupture is observed in patients with larger aneurysms. According to the literature, contradictory results concerning the relationship between atmospheric pressure and aneurysm size have been reported. In this paper, we assessed the influence of changes in atmospheric pressure on abdominal aneurysm ruptures in relationship to the aneurysm's size. The records of 223 patients with ruptured abdominal aneurysms were evaluated. All of the patients had been admitted to the department in the period 1997-2007 from the Silesia region. The atmospheric pressures on the day of the rupture and on the days both before the rupture and between the rupture events were compared. The size of the aneurysm was also considered in the analysis. There were no statistically significant differences in pressure between the days of rupture and the remainder of the days within an analysed period. The highest frequency of the admission of patients with a ruptured aortic aneurysm was observed during periods of winter and spring, when the highest mean values of atmospheric pressure were observed; however, this observation was not statistically confirmed. A statistically non-significant trend towards the higher rupture of large aneurysms (> 7 cm) was observed in the cases where the pressure increased between the day before the rupture and the day of the rupture. This trend was particularly pronounced in patients suffering from hypertension (p = 0.1). The results of this study do not support the hypothesis that there is a direct link between atmospheric pressure values and abdominal aortic aneurysm ruptures.

Wall shear stress in intracranial aneurysms and adjacent arteries☆

PubMed Central

Wang, Fuyu; Xu, Bainan; Sun, Zhenghui; Wu, Chen; Zhang, Xiaojun

2013-01-01

Hemodynamic parameters play an important role in aneurysm formation and growth. However, it is difficult to directly observe a rapidly growing de novo aneurysm in a patient. To investigate possible associations between hemodynamic parameters and the formation and growth of intracranial aneurysms, the present study constructed a computational model of a case with an internal carotid artery aneurysm and an anterior communicating artery aneurysm, based on the CT angiography findings of a patient. To simulate the formation of the anterior communicating artery aneurysm and the growth of the internal carotid artery aneurysm, we then constructed a model that virtually removed the anterior communicating artery aneurysm, and a further two models that also progressively decreased the size of the internal carotid artery aneurysm. Computational simulations of the fluid dynamics of the four models were performed under pulsatile flow conditions, and wall shear stress was compared among the different models. In the three aneurysm growth models, increasing size of the aneurysm was associated with an increased area of low wall shear stress, a significant decrease in wall shear stress at the dome of the aneurysm, and a significant change in the wall shear stress of the parent artery. The wall shear stress of the anterior communicating artery remained low, and was significantly lower than the wall shear stress at the bifurcation of the internal carotid artery or the bifurcation of the middle cerebral artery. After formation of the anterior communicating artery aneurysm, the wall shear stress at the dome of the internal carotid artery aneurysm increased significantly, and the wall shear stress in the upstream arteries also changed significantly. These findings indicate that low wall shear stress may be associated with the initiation and growth of aneurysms, and that aneurysm formation and growth may influence hemodynamic parameters in the local and adjacent arteries. PMID:25206394

Alteration of intraaneurysmal hemodynamics by placement of a self-expandable stent. Laboratory investigation.

PubMed

Tateshima, Satoshi; Tanishita, Kazuo; Hakata, Yasuhiro; Tanoue, Shin-ya; Viñuela, Fernando

2009-07-01

Development of a flexible self-expanding stent system and stent-assisted coiling technique facilitates endovascular treatment of wide-necked brain aneurysms. The hemodynamic effect of self-expandable stent placement across the neck of a brain aneurysm has not been well documented in patient-specific aneurysm models. Three patient-specific silicone aneurysm models based on clinical images were used in this study. Model 1 was constructed from a wide-necked internal carotid artery-ophthalmic artery aneurysm, and Models 2 and 3 were constructed from small wide-necked middle cerebral artery aneurysms. Neuroform stents were placed in the in vitro aneurysm models, and flow structures were compared before and after the stent placements. Flow velocity fields were acquired with particle imaging velocimetry. In Model 1, a clockwise, single-vortex flow pattern was observed in the aneurysm dome before stenting was performed. There were multiple vortices, and a very small fast flow stream was newly formed in the aneurysm dome after stenting. The mean intraaneurysmal flow velocity was reduced by approximately 23-40%. In Model 2, there was a clockwise vortex flow in the aneurysm dome and another small counterclockwise vortex in the tip of the aneurysm dome before stenting. The small vortex area disappeared after stenting, and the mean flow velocity in the aneurysm dome was reduced by 43-64%. In Model 3, a large, counterclockwise, single vortex was seen in the aneurysm dome before stenting. Multiple small vortices appeared in the aneurysm dome after stenting, and the mean flow velocity became slower by 22-51%. The flexible self-expandable stents significantly altered flow velocity and also flow structure in these aneurysms. Overall flow alterations by the stent appeared favorable for the long-term durability of aneurysm embolization. The possibility that the placement of a low-profile self-expandable stent might induce unfavorable flow patterns such as a fast flow stream in the aneurysm dome cannot be excluded.

Intracranial Aneurysms of Neuro-Ophthalmologic Relevance.

PubMed

Micieli, Jonathan A; Newman, Nancy J; Barrow, Daniel L; Biousse, Valérie

2017-12-01

Intracranial saccular aneurysms are acquired lesions that often present with neuro-ophthalmologic symptoms and signs. Recent advances in neurosurgical techniques, endovascular treatments, and neurocritical care have improved the optimal management of symptomatic unruptured aneurysms, but whether the chosen treatment has an impact on neuro-ophthalmologic outcomes remains debated. A review of the literature focused on neuro-ophthalmic manifestations and treatment of intracranial aneurysms with specific relevance to neuro-ophthalmologic outcomes was conducted using Ovid MEDLINE and EMBASE databases. Cavernous sinus aneurysms were not included in this review. Surgical clipping vs endovascular coiling for aneurysms causing third nerve palsies was compared in 13 retrospective studies representing 447 patients. Complete recovery was achieved in 78% of surgical patients compared with 44% of patients treated with endovascular coiling. However, the complication rate, hospital costs, and days spent in intensive care were reported as higher in surgically treated patients. Retrospective reviews of surgical clipping and endovascular coiling for all ocular motor nerve palsies (third, fourth, or sixth cranial nerves) revealed similar results of complete resolution in 76% and 49%, respectively. Improvement in visual deficits related to aneurysmal compression of the anterior visual pathways was also better among patients treated with clipping than with coiling. The time to treatment from onset of visual symptoms was a predictive factor of visual recovery in several studies. Few reports have specifically assessed the improvement of visual deficits after treatment with flow diverters. Decisions regarding the choice of therapy for intracranial aneurysms causing neuro-ophthalmologic signs ideally should be made at high-volume centers with access to both surgical and endovascular treatments. The status of the patient, location of the aneurysm, and experience of the treating physicians are important factors to consider. Although a higher rate of visual recovery was reported with neurosurgical clipping, this must be weighed against the potentially longer intensive care stays and increased early morbidity.

Effect of improved endograft design on outcome of endovascular aneurysm repair.

PubMed

Torella, Francesco

2004-08-01

This study was undertaken to identify factors that lead to improvements in the results of endovascular aneurysm repair, with particular focus on new endograft design. We analyzed data for patients enrolled in the European Collaborators on Stent Graft Techniques for Abdominal Aortic Aneurysm Repair (EUROSTAR) registry, and compared those for endografts now withdrawn from the market with those for endografts currently in use. Patients in whom a variety of endograft types were used in small numbers were excluded. Postoperative and long-term outcomes were initially compared with univariate analyses, and subsequently multivariate tests were used to adjust for baseline differences between the 2 groups. The main outcome measures were freedom from a variety of secondary interventions, aneurysm rupture, and death. Some 1224 patients received "withdrawn" endografts, and 2768 patients received "current" endografts. The 2 groups were generally similar, but patients with current devices were more often men, significantly older, more frequently unfit for open surgery, and had larger aneurysms with wider necks. Of no surprise, current endografts were also more often used by experienced (>60 previous cases) surgical teams (44% vs 20%; P <.0001). Thirty-day clinical outcomes were comparable in the 2 groups, although patients with withdrawn devices were less likely to have type II endoleak (9.2% vs 5.5%; P <.0001), and those with current devices had a shorter mean hospital stay (5.4 vs 6.8 days; P <.0001). At 3 years more patients with current devices were free from secondary transfemoral intervention (88.4% vs 76%; P <.0001) and conversion to open repair (95.4% vs 93.4%; P =.007). Aneurysm-related mortality at 3 years, defined as death due to aneurysm rupture or within 30 days of a secondary intervention, was also less frequent with current endografts (2.7% vs 4.4%; P =.02). Aneurysm rupture at 3 years was infrequent (0.8% vs 1.8%; P =.07). At multivariate analysis the use of current devices was a protective factor against late conversion to open repair (hazard ratio, 0.49; 95% confidence interval, 0.28-0.86; P =.014) and aneurysm-related death (hazard ratio, 0.51, 95% confidence interval, 0.34-0.75; P =.0008). Larger aneurysm or neck diameter and shorter neck length were also associated with late conversion to open repair; larger aneurysm diameter, older age, and unfitness for open surgery were predictive of aneurysm-related death. Modern endograft design has improved the results of endovascular aneurysm repair.

Unruptured internal carotid artery bifurcation aneurysms: general features and overall results after modern treatment.

PubMed

La Pira, Biagia; Brinjikji, Waleed; Burrows, Anthony M; Cloft, Harry J; Vine, Roanna L; Lanzino, Giuseppe

2016-11-01

Internal carotid artery bifurcation aneurysms (ICAbifAs) present unique challenges to endovascular and surgical operators, and little is known about their natural history. We reviewed our institution's experience with ICAbifAs studying outcomes of surgical and endovascular management and natural history. Consecutive patients with unruptured ICAbifAs evaluated and/or treated over an 8-year interval were studied. Baseline demographics, neurovascular risk factors, aneurysm location and size, clinical presentation, treatment recommendations, and outcomes were prospectively collected and retrospectively analyzed. Continuous variables were compared with Student's t test and categorical variables with Chi-square tests. Fifty-nine patients with 61 unruptured ICAbifAs were included. Seven aneurysms were treated surgically (11.5 %), 22 underwent endovascular treatment (36 %), and 32 were managed conservatively (52.5 %). In the surgical group, short- and long-term complete aneurysm occlusion rates were 100 % with no cases of perioperative or long-term permanent morbidity or treatment-related mortality. In the endovascular group, two patients (11.7 %) with giant aneurysms had perioperative thromboembolic events with transient morbidity. There was one case of aneurysm rupture at follow-up in a giant aneurysm treated with partial coil embolization. Complete/near-complete occlusion rates were 63 %. There was one case of aneurysm rupture after 114 aneurysm-years of follow-up in the conservative management group (0.89 %/year), but no ruptures were observed in small aneurysms selected for conservative management. Unruptured small ICAbifAs have a benign natural history. In patients selected for treatment, excellent results can be achieved in the vast majority of patients with judicious use of endovascular and surgical therapy.

Fluoroquinolone use and risk of aortic aneurysm and dissection: nationwide cohort study

PubMed Central

Inghammar, Malin; Svanström, Henrik

2018-01-01

Abstract Objective To investigate whether oral fluoroquinolone use is associated with an increased risk of aortic aneurysm or dissection. Design Nationwide historical cohort study using linked register data on patient characteristics, filled prescriptions, and cases of aortic aneurysm or dissection. Setting Sweden, July 2006 to December 2013. Participants 360 088 treatment episodes of fluoroquinolone use (78%ciprofloxacin) and propensity score matched comparator episodes of amoxicillin use (n=360 088). Main outcome measures Cox regression was used to estimate hazard ratios for a first diagnosis of aortic aneurysm or dissection, defined as admission to hospital or emergency department for, or death due to, aortic aneurysm or dissection, within 60 days from start of treatment. Results Within the 60 day risk period, the rate of aortic aneurysm or dissection was 1.2 cases per 1000 person years among fluoroquinolone users and 0.7 cases per 1000 person years among amoxicillin users. Fluoroquinolone use was associated with an increased risk of aortic aneurysm or dissection (hazard ratio 1.66 (95% confidence interval 1.12 to 2.46)), with an estimated absolute difference of 82 (95% confidence interval 15 to 181) cases of aortic aneurysm or dissection by 60 days per 1 million treatment episodes. In a secondary analysis, the hazard ratio for the association with fluoroquinolone use was 1.90 (1.22 to 2.96) for aortic aneurysm and 0.93 (0.38 to 2.29) for aortic dissection. Conclusions In a propensity score matched cohort, fluoroquinolone use was associated with an increased risk of aortic aneurysm or dissection. This association appeared to be largely driven by aortic aneurysm. PMID:29519881

Flow and wall shear stress characterization after endovascular aneurysm repair and endovascular aneurysm sealing in an infrarenal aneurysm model.

PubMed

Boersen, Johannes T; Groot Jebbink, Erik; Versluis, Michel; Slump, Cornelis H; Ku, David N; de Vries, Jean-Paul P M; Reijnen, Michel M P J

2017-12-01

Endovascular aneurysm repair (EVAR) with a modular endograft has become the preferred treatment for abdominal aortic aneurysms. A novel concept is endovascular aneurysm sealing (EVAS), consisting of dual endoframes surrounded by polymer-filled endobags. This dual-lumen configuration is different from a bifurcation with a tapered trajectory of the flow lumen into the two limbs and may induce unfavorable flow conditions. These include low and oscillatory wall shear stress (WSS), linked to atherosclerosis, and high shear rates that may result in thrombosis. An in vitro study was performed to assess the impact of EVAR and EVAS on flow patterns and WSS. Four abdominal aortic aneurysm phantoms were constructed, including three stented models, to study the influence of the flow divider on flow (Endurant [Medtronic, Minneapolis, Minn], AFX [Endologix, Irvine, Calif], and Nellix [Endologix]). Experimental models were tested under physiologic resting conditions, and flow was visualized with laser particle imaging velocimetry, quantified by shear rate, WSS, and oscillatory shear index (OSI) in the suprarenal aorta, renal artery (RA), and common iliac artery. WSS and OSI were comparable for all models in the suprarenal aorta. The RA flow profile in the EVAR models was comparable to the control, but a region of lower WSS was observed on the caudal wall compared with the control. The EVAS model showed a stronger jet flow with a higher shear rate in some regions compared with the other models. Small regions of low WSS and high OSI were found near the distal end of all stents in the common iliac artery compared with the control. Maximum shear rates in each region of interest were well below the pathologic threshold for acute thrombosis. The different stent designs do not influence suprarenal flow. Lower WSS is observed in the caudal wall of the RA after EVAR and a higher shear rate after EVAS. All stented models have a small region of low WSS and high OSI near the distal outflow of the stents. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Relationship between Two Types of Coil Packing Densities Relative to Aneurysm Size.

PubMed

Park, Keun Young; Kim, Byung Moon; Ihm, Eun Hyun; Baek, Jang Hyun; Kim, Dong Joon; Kim, Dong Ik; Huh, Seung Kon; Lee, Jae Whan

2015-01-01

Coil packing density (PD) can be calculated via a formula (PDF ) or software (PDS ). Two types of PD can be different from each other for same aneurysm. This study aimed to evaluate the interobserver agreement and relationships between the 2 types of PD relative to aneurysm size. Consecutive 420 saccular aneurysms were treated with coiling. PD (PDF , [coil volume]/[volume calculated by formula] and PDS, [coil volume]/[volume measured by software]) was calculated and prospectively recorded. Interobserver agreement was evaluated between PDF and PDS . Additionally, the relationships between PDF and PDS relative to aneurysm size were subsequently analyzed. Interobserver agreement for PDF and PDS was excellent (Intraclass correlation coefficient, PDF ; 0.967 and PDS ; 0.998). The ratio of PDF and PDS was greater for smaller aneurysms and converged toward 1.0 as the maximum dimension (DM ) of aneurysm increased. Compared with PDS , PDF was overestimated by a mean of 28% for DM < 5 mm, by 17% for 5 mm ≤ DM < 10 mm, and by 9% for DM ≥ 10 mm (P < 0.01). Interobserver agreement for PDF and PDS was excellent. However, PDF was overestimated in smaller aneurysms and converged to PDS as aneurysm size increased. Copyright © 2014 by the American Society of Neuroimaging.

Ten-Year Follow-Up of Endovascular Aneurysm Treatment with Talent Stent-Grafts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pitton, Michael B., E-mail: pitton@radiologie.klinik.uni-mainz.de; Scheschkowski, Tobias; Ring, Markus

2009-09-15

The purpose of this study was to evaluate the clinical results, complications, and secondary interventions during long-term follow-up after endovascular aneurysm repair (EVAR) and to investigate the impact of endoleak sizes on aneurysm shrinkage. From 1997 to March 2007, 127 patients (12 female, 115 male; age, 73.0 {+-} 7.2 years) with abdominal aortic aneurysms were treated with Talent stent-grafts. Follow-up included clinical visits, contrast-enhanced MDCT, and radiographs at 3, 6, and 12 months and then annually. Results were analyzed with respect to clinical outcome, secondary interventions, endoleak rate and management, and change in aneurysm size. There was no need formore » primary conversion surgery. Thirty-day mortality was 1.6% (two myocardial infarctions). Procedure-related morbidity was 2.4% (paraplegia, partial infarction of one kidney, and inguinal bleeding requiring surgery). Mean follow-up was 47.7 {+-} 34.2 months (range, 0-123 months). Thirty-nine patients died during follow-up; three of the deaths were related to aneurysm (aneurysm rupture due to endoleak, n = 1; secondary surgical reintervention n = 2). During follow-up, a total of 29 secondary procedures were performed in 19 patients, including 14 percutaneous procedures (10 patients) and 15 surgical procedures (12 patients), including 4 cases with late conversion to open aortic repair (stent-graft infection, n = 1; migration, endoleak, or endotension, n = 3). Overall mean survival was 84.5 {+-} 4.7 months. Mean survival and freedom from any event was 66.7 {+-} 4.5 months. MRI depicted significantly more endoleaks compared to MDCT (23.5% vs. 14.3%; P < 0.01). Patients in whom all aneurysm side branches were occluded prior to stent-grafting showed a significantly reduced incidence of large endoleaks. Endoleaks >10% of the aneurysm area were associated with reduced aneurysm shrinkage compared to no endoleaks or <10% endoleaks ({Delta} at 3 years, -1.8% vs. -12.0%; P < 0.05). In conclusion, endovascular aneurysm treatment with Talent stent-grafts demonstrated encouraging long-term results with moderate secondary intervention rates. Primary occlusion of all aortic side branches reduced the incidence of large endoleaks. Large endoleaks significantly impaired aneurysm shrinkage, whereas small endoleaks did not.« less

Coil Embolization for Intracranial Aneurysms

PubMed Central

2006-01-01

Executive Summary Objective To determine the effectiveness and cost-effectiveness of coil embolization compared with surgical clipping to treat intracranial aneurysms. The Technology Endovascular coil embolization is a percutaneous approach to treat an intracranial aneurysm from within the blood vessel without the need of a craniotomy. In this procedure, a microcatheter is inserted into the femoral artery near the groin and navigated to the site of the aneurysm. Small helical platinum coils are deployed through the microcatheter to fill the aneurysm, and prevent it from further expansion and rupture. Health Canada has approved numerous types of coils and coil delivery systems to treat intracranial aneurysms. The most favoured are controlled detachable coils. Coil embolization may be used with other adjunct endovascular devices such as stents and balloons. Background Intracranial Aneurysms Intracranial aneurysms are the dilation or ballooning of part of a blood vessel in the brain. Intracranial aneurysms range in size from small (<12 mm in diameter) to large (12–25 mm), and to giant (>25 mm). There are 3 main types of aneurysms. Fusiform aneurysms involve the entire circumference of the artery; saccular aneurysms have outpouchings; and dissecting aneurysms have tears in the arterial wall. Berry aneurysms are saccular aneurysms with well-defined necks. Intracranial aneurysms may occur in any blood vessel of the brain; however, they are most commonly found at the branch points of large arteries that form the circle of Willis at the base of the brain. In 85% to 95% of patients, they are found in the anterior circulation. Aneurysms in the posterior circulation are less frequent, and are more difficult to treat surgically due to inaccessibility. Most intracranial aneurysms are small and asymptomatic. Large aneurysms may have a mass effect, causing compression on the brain and cranial nerves and neurological deficits. When an intracranial aneurysm ruptures and bleeds, resulting in a subarachnoid hemorrhage (SAH), the mortality rate can be 40% to 50%, with severe morbidity of 10% to 20%. The reported overall risk of rupture is 1.9% per year and is higher for women, cigarette smokers, and cocaine users, and in aneurysms that are symptomatic, greater than 10 mm in diameter, or located in the posterior circulation. If left untreated, there is a considerable risk of repeat hemorrhage in a ruptured aneurysm that results in increased mortality. In Ontario, intracranial aneurysms occur in about 1% to 4% of the population, and the annual incidence of SAH is about 10 cases per 100,000 people. In 2004-2005, about 660 intracranial aneurysm repairs were performed in Ontario. Treatment of Intracranial Aneurysms Treatment of an unruptured aneurysm attempts to prevent the aneurysm from rupturing. The treatment of a ruptured intracranial aneurysm aims to prevent further hemorrhage. There are 3 approaches to treating an intracranial aneurysm. Small, asymptomatic aneurysms less than 10 mm in diameter may be monitored without any intervention other than treatment for underlying risk factors such as hypertension. Open surgical clipping, involves craniotomy, brain retraction, and placement of a silver clip across the neck of the aneurysm while a patient is under general anesthesia. This procedure is associated with surgical risks and neurological deficits. Endovascular coil embolization, introduced in the 1990s, is the health technology under review. Literature Review Methods The Medical Advisory Secretariat searched the International Health Technology Assessment (INAHTA) Database and the Cochrane Database of Systematic Reviews to identify relevant systematic reviews. OVID Medline, Medline In-Process and Other Non-Indexed Citations, and Embase were searched for English-language journal articles that reported primary data on the effectiveness or cost-effectiveness of treatments for intracranial aneurysms, obtained in a clinical setting or analyses of primary data maintained in registers or institutional databases. Internet searches of Medscape and manufacturers’ databases were conducted to identify product information and recent reports on trials that were unpublished but that were presented at international conferences. Four systematic reviews, 3 reports on 2 randomized controlled trials comparing coil embolization with surgical clipping of ruptured aneurysms, 30 observational studies, and 3 economic analysis reports were included in this review. Results Safety and Effectiveness Coil embolization appears to be a safe procedure. Complications associated with coil embolization ranged from 8.6% to 18.6% with a median of about 10.6%. Observational studies showed that coil embolization is associated with lower complication rates than surgical clipping (permanent complication 3-7% versus 10.9%; overall 23% versus 46% respectively, p=0.009). Common complications of coil embolization are thrombo-embolic events (2.5%–14.5%), perforation of aneurysm (2.3%–4.7%), parent artery obstruction (2%–3%), collapsed coils (8%), coil malposition (14.6%), and coil migration (0.5%–3%). Randomized controlled trials showed that for ruptured intracranial aneurysms with SAH, suitable for both coil embolization and surgical clipping (mostly saccular aneurysms <10 mm in diameter located in the anterior circulation) in people with good clinical condition:Coil embolization resulted in a statistically significant 23.9% relative risk reduction and 7% absolute risk reduction in the composite rate of death and dependency compared to surgical clipping (modified Rankin score 3–6) at 1-year. The advantage of coil embolization over surgical clipping varies widely with aneurysm location, but endovascular treatment seems beneficial for all sites. There were less deaths in the first 7 years following coil embolization compared to surgical clipping (10.8% vs 13.7%). This survival benefit seemed to be consistent over time, and was statistically significant (log-rank p= 0.03). Coil embolization is associated with less frequent MRI-detected superficial brain deficits and ischemic lesions at 1-year. The 1- year rebleeding rate was 2.4% after coil embolization and 1% for surgical clipping. Confirmed rebleeding from the repaired aneurysm after the first year and up to year eight was low and not significantly different between coil embolization and surgical clipping (7 patients for coil embolization vs 2 patients for surgical clipping, log-rank p=0.22). Observational studies showed that patients with SAH and good clinical grade had better 6-month outcomes and lower risk of symptomatic cerebral vasospasm after coil embolization compared to surgical clipping. For unruptured intracranial aneurysms, there were no randomized controlled trials that compared coil embolization to surgical clipping. Large observational studies showed that: The risk of rupture in unruptured aneurysms less than 10 mm in diameter is about 0.05% per year for patients with no pervious history of SAH from another aneurysm. The risk of rupture increases with history of SAH and as the diameter of the aneurysm reaches 10 mm or more. Coil embolization reduced the composite rate of in hospital deaths and discharge to long-term or short-term care facilities compared to surgical clipping (Odds Ratio 2.2, 95% CI 1.6–3.1, p<0.001). The improvement in discharge disposition was highest in people older than 65 years. In-hospital mortality rate following treatment of intracranial aneurysm ranged from 0.5% to 1.7% for coil embolization and from 2.1% to 3.5% for surgical clipping. The overall 1-year mortality rate was 3.1% for coil embolization and 2.3% for surgical clipping. One-year morbidity rate was 6.4% for coil embolization and 9.8% for surgical clipping. It is not clear whether these differences were statistically significant. Coil embolization is associated with shorter hospital stay compared to surgical clipping. For both ruptured and unruptured aneurysms, the outcome of coil embolization does not appear to be dependent on age, whereas surgical clipping has been shown to yield worse outcome for patients older than 64 years. Angiographic Efficiency and Recurrences The main drawback of coil embolization is its low angiographic efficiency. The percentage of complete aneurysm occlusion after coil embolization (27%–79%, median 55%) remains lower than that achieved with surgical clipping (82%–100%). However, about 90% of coiled aneurysms achieve near total occlusion or better. Incompletely coiled aneurysms have been shown to have higher aneurysm recurrence rates ranging from 7% to 39% for coil embolization compared to 2.9% for surgical clipping. Recurrence is defined as refilling of the neck, sac, or dome of a successfully treated aneurysm as shown on an angiogram. The long-term clinical significance of incomplete occlusion following coil embolization is unknown, but in one case series, 20% of patients had major recurrences, and 50% of these required further treatment. Long-Term Outcomes A large international randomized trial reported that the survival benefit from coil embolization was sustained for at least 7 years. The rebleeding rate between year 2 and year 8 following coil embolization was low and not significantly different from that of surgical clipping. However, high quality long-term angiographic evidence is lacking. Accordingly, there is uncertainty about long-term occlusion status, coil durability, and recurrence rates. While surgical clipping is associated with higher immediate procedural risks, its long-term effectiveness has been established. Indications and Contraindications Coil embolization offers treatment for people at increased risk for craniotomy, such as those over 65 years of age, with poor clinical status, or with comorbid conditions. The technology also makes it possible to treat surgical high-risk aneurysms. Not all aneurysms are suitable for coil embolization. Suitability depends on the size, anatomy, and location of the aneurysm. Aneurysms more than 10 mm in diameter or with an aneurysm neck greater than or equal to 4 mm are less likely to achieve total occlusion. They are also more prone to aneurysm recurrences and to complications such as coil compaction or parent vessel occlusion. Aneurysms with a dome to neck ratio of less than 1 have been shown to have lower obliteration rates and poorer outcome following coil embolization. Furthermore, aneurysms in the middle cerebral artery bifurcation are less suitable for coil embolization. For some aneurysms, treatment may require the use of both coil embolization and surgical clipping or adjunctive technologies, such as stents and balloons, to obtain optimal results. Diffusion Information from 3 countries indicates that coil embolization is a rapidly diffusing technology. For example, it accounted for about 40% of aneurysm treatments in the United Kingdom. In Ontario, coil embolization is an insured health service, with the same fee code and fee schedule as open surgical repair requiring craniotomy. Other costs associated with coil embolization are covered under hospitals’ global budgets. Utilization data showed that in 2004-2005, coil embolization accounted for about 38% (251 cases) of all intracranial aneurysm repairs in the province. With the 2005 publication of the positive long-term survival data from the International Subarachnoid Aneursym Trial, the pressure for diffusion will likely increase. Economic Analysis Recent economic studies show that treatment of unruptured intracranial aneurysms smaller than 10 mm in diameter in people with no previous history of SAH, either by coil embolization or surgical clipping, would not be effective or cost-effective. However, in patients with aneurysms that are greater than or equal to 10 mm or symptomatic, or in patients with a history of SAH, treatment appears to be cost-effective. In Ontario, the average device cost of coil embolization per case was estimated to be about $7,500 higher than surgical clipping. Assuming that the total number of intracranial aneurysm repairs in Ontario increases to 750 in the fiscal year of 2007, and assuming that up to 60% (450 cases) of these will be repaired by coil embolization, the difference in device costs for the 450 cases (including a 15% recurrence rate) would be approximately $3.8 million. This figure does not include capital costs (e.g. $3 million for an angiosuite), additional human resources required, or costs of follow-up. The increase in expenditures associated with coil embolization may be offset partially, by shorter operating room times and hospitalization stays for endovascular repair of unruptured aneurysms; however, the impact of these cost savings is probably not likely to be greater than 25% of the total outlay since the majority of cases involve ruptured aneurysms. Furthermore, the recent growth in aneurysm repair has predominantly been in the area of coil embolization presumably for patients for whom surgical clipping would not be advised; therefore, no offset of surgical clipping costs could be applied in such cases. For ruptured aneurysms, downstream cost savings from endovascular repair are likely to be minimal even though the savings for individual cases may be substantial due to lower perioperative complications for endovascular aneurysm repair. Guidelines The two Guidance documents issued by the National Institute of Clinical Excellence (UK) in 2005 support the use of coil embolization for both unruptured and ruptured (SAH) intracranial aneurysms, provided that procedures are in place for informed consent, audit, and clinical governance, and that the procedure is performed in specialist units with expertise in the endovascular treatment of intracranial aneurysms. Conclusion For people in good clinical condition following subarachnoid hemorrhage from an acute ruptured intracranial aneurysm suitable for either surgical clipping or endovascular repair, coil embolization results in improved independent survival in the first year and improved survival for up to seven years compared to surgical clipping. The rebleeding rate is low and not significantly different between the two procedures after the first year. However, there is uncertainty regarding the long-term occlusion status, durability of the stent graft, and long-term complications. For people with unruptured aneurysms, level 4 evidence suggests that coil embolization may be associated with comparable or less mortality and morbidity, shorter hospital stay, and less need for discharge to short-term rehabilitation facilities. The greatest benefit was observed in people over 65 years of age. In these patients, the decision regarding treatment needs to be based on the assessment of the risk of rupture against the risk of the procedure, as well as the morphology of the aneurysm. In people who require treatment for intracranial aneurysm, but for whom surgical clipping is too risky or not feasible, coil embolization provides survival benefits over surgical clipping, even though the outcomes may not be as favourable as in people in good clinical condition and with small aneurysms. The procedure may be considered under the following circumstances provided that the aneurysm is suitable for coil embolization: Patients in poor/unstable clinical or neurological state Patients at high risk for surgical repair (e.g. people>age 65 or with comorbidity), or Aneurysm(s) with poor accessibility or visibility for surgical treatment due to their location (e.g. ophthalmic or basilar tip aneurysms) Compared to small aneurysms with a narrow neck in the anterior circulation, large aneurysms (> 10 mm in diameter), aneurysms with a wide neck (>4mm in diameter), and aneurysms in the posterior circulation have lower occlusion rates and higher rate of hemorrhage when treated with coil embolization. The extent of aneurysm obliteration after coil embolization remains lower than that achieved with surgical clipping. Aneurysm recurrences after successful coiling may require repeat treatment with endovascular or surgical procedures. Experts caution that long-term angiographic outcomes of coil embolization are unknown at this time. Informed consent for and long-term follow-up after coil embolization are recommended. The decision to treat an intracranial aneurysm with surgical clipping or coil embolization needs to be made jointly by the neurosurgeon and neuro-intervention specialist, based on the clinical status of the patient, the size and morphology of the aneurysm, and the preference of the patient. The performance of endovascular coil embolization should take place in centres with expertise in both neurosurgery and endovascular neuro-interventions, with adequate treatment volumes to maintain good outcomes. Distribution of the technology should also take into account that patients with SAH should be treated as soon as possible with minimal disruption. PMID:23074479

HiFiVS Modeling of Flow Diverter Deployment Enables Hemodynamic Characterization of Complex Intracranial Aneurysm Cases

PubMed Central

Xiang, Jianping; Damiano, Robert J.; Lin, Ning; Snyder, Kenneth V.; Siddiqui, Adnan H.; Levy, Elad I.; Meng, Hui

2016-01-01

Object Flow diversion via Pipeline Embolization Device (PED) represents the most recent advancement in endovascular therapy of intracranial aneurysms. This exploratory study aims at a proof of concept for an advanced device-modeling tool in conjunction with computational fluid dynamics (CFD) to evaluate flow modification effects by PED in real treatment cases. Methods We performed computational modeling of three PED-treated complex aneurysm cases. Case I had a fusiform vertebral aneurysm treated with a single PED. Case II had a giant internal carotid artery (ICA) aneurysm treated with 2 PEDs. Case III consisted of two tandem ICA aneurysms (a and b) treated by a single PED. Our recently developed high fidelity virtual stenting (HiFiVS) technique was used to recapitulate the clinical deployment process of PEDs in silico for these three cases. Pre- and post-treatment aneurysmal hemodynamics using CFD simulation was analyzed. Changes in aneurysmal flow velocity, inflow rate, and wall shear stress (WSS) (quantifying flow reduction) and turnover time (quantifying stasis) were calculated and compared with clinical outcome. Results In Case I (occluded within the first 3 months), the aneurysm experienced the most drastic aneurysmal flow reduction after PED placement, where the aneurysmal average velocity, inflow rate and average WSS was decreased by 76.3%, 82.5% and 74.0%, respectively, while the turnover time was increased to 572.1% of its pre-treatment value. In Case II (occluded at 6 months), aneurysmal average velocity, inflow rate and average WSS were decreased by 39.4%, 38.6%, and 59.1%, respectively, and turnover time increased to 163.0%. In Case III, Aneurysm III-a (occluded at 6 months) experienced decrease by 38.0%, 28.4%, and 50.9% in aneurysmal average velocity, inflow rate and average WSS, respectively and increase to 139.6% in turnover time, which was quite similar to Aneurysm II. Surprisingly, the adjacent Aneurysm III-b experienced more substantial flow reduction (decrease by 77.7%, 53.0%, and 84.4% in average velocity, inflow rate and average WSS, respectively, and increase to 213.0% in turnover time) than Aneurysm III-a, which qualitatively agreed with angiographic observation at 3-month follow-up. However, Aneurysm III-b remained patent at both 6 months and 9 months. A closer examination of the vascular anatomy of Case III revealed blood draining to the ophthalmic artery off Aneurysm III-b, which may have prevented its complete thrombosis. Conclusion This proof-of-concept study demonstrates that HiFiVE modeling of flow diverter deployment enables detailed characterization of hemodynamic alteration by PED placement. Post-treatment aneurysmal flow reduction may be correlated with aneurysm occlusion outcome. However, predicting aneurysm treatment outcome by flow diverters also requires consideration of other factors including vascular anatomy. PMID:26090829

Hemodynamic simulations in coronary aneurysms of a patient with Kawasaki Disease

NASA Astrophysics Data System (ADS)

Sengupta, Dibyendu; Marsden, Alison; Burns, Jane

2010-11-01

Kawasaki Disease is the leading cause of acquired pediatric heart disease, and can cause large coronary artery aneurysms in untreated cases. A simulation case study has been performed for a 10-year-old male patient with coronary aneurysms. Specialized coronary boundary conditions along with a lumped parameter heart model mimic the interactions between the ventricles and the coronary arteries, achieving physiologic pressure and flow waveforms. Results show persistent low shear stress in the aneurismal regions, and abnormally high shear at the aneurysm neck. Correlation functions have been derived to compare wall shear stress and wall shear stress gradients with recirculation time with the idea of localizing zones of calcification and thrombosis. Results are compared with those of an artificially created normal coronary geometry for the same patient. The long-term goal of this work is to develop links between hemodynamics and thrombotic risk to assist in clinical decision-making.

A meta-analysis of aneurysm formation in laser assisted vascular anastomosis (LAVA)

NASA Astrophysics Data System (ADS)

Chen, Chen; Peng, Fei; Xu, Dahai; Cheng, Qinghua

2009-08-01

Laser assisted vascular anastomosis (LAVA) is looked as a particularly promising non-suture method in future. However, aneurysm formation is one of the main reasons delay the clinical application of LAVA. Some scientists investigated the incidence of aneurysms in animal model. To systematically analyze the literature on reported incidence of aneurysm formation in LAVA therapy, we performed a meta-analysis comparing LAVA with conventional suture anastomosis (CSA) in animal model. Data were systematically retrieved and selected from PUBMED. In total, 23 studies were retrieved. 18 studies were excluded, and 5 studies involving 647 animals were included. Analysis suggested no statistically significant difference between LAVA and CSA (OR 1.24, 95%CI 0.66-2.32, P=0.51). Result of meta analysis shows that the technology of LAVA is very close to clinical application.

Transitional hemodynamics in intracranial aneurysms - Comparative velocity investigations with high resolution lattice Boltzmann simulations, normal resolution ANSYS simulations, and MR imaging.

PubMed

Jain, Kartik; Jiang, Jingfeng; Strother, Charles; Mardal, Kent-André

2016-11-01

Blood flow in intracranial aneurysms has, until recently, been considered to be disturbed but still laminar. Recent high resolution computational studies have demonstrated, in some situations, however, that the flow may exhibit high frequency fluctuations that resemble weakly turbulent or transitional flow. Due to numerous assumptions required for simplification in computational fluid dynamics (CFD) studies, the occurrence of these events, in vivo, remains unsettled. The detection of these fluctuations in aneurysmal blood flow, i.e., hemodynamics by CFD, poses additional challenges as such phenomena cannot be captured in clinical data acquisition with magnetic resonance (MR) due to inadequate temporal and spatial resolutions. The authors' purpose was to address this issue by comparing results from highly resolved simulations, conventional resolution laminar simulations, and MR measurements, identify the differences, and identify their causes. Two aneurysms in the basilar artery, one with disturbed yet laminar flow and the other with transitional flow, were chosen. One set of highly resolved direct numerical simulations using the lattice Boltzmann method (LBM) and another with adequate resolutions under laminar flow assumption were conducted using a commercially available ANSYS Fluent solver. The velocity fields obtained from simulation results were qualitatively and statistically compared against each other and with MR acquisition. Results from LBM, ANSYS Fluent, and MR agree well qualitatively and quantitatively for one of the aneurysms with laminar flow in which fluctuations were <80 Hz. The comparisons for the second aneurysm with high fluctuations of > ∼ 600 Hz showed vivid differences between LBM, ANSYS Fluent, and magnetic resonance imaging. After ensemble averaging and down-sampling to coarser space and time scales, these differences became minimal. A combination of MR derived data and CFD can be helpful in estimating the hemodynamic environment of intracranial aneurysms. Adequately resolved CFD would suffice gross assessment of hemodynamics, potentially in a clinical setting, and highly resolved CFD could be helpful in a detailed and retrospective understanding of the physiological mechanisms.

Mortality After Elective and Ruptured Abdominal Aortic Aneurysm Surgical Repair: 12-Year Single-Center Experience of Estonia.

PubMed

Lieberg, J; Pruks, L-L; Kals, M; Paapstel, K; Aavik, A; Kals, J

2018-06-01

Abdominal aortic aneurysm is a degenerative vascular pathology with high mortality due to its rupture, which is why timely treatment is crucial. The current single-center retrospective study was undertaken to analyze short- and long-term all-cause mortality after operative treatment of abdominal aortic aneurysm and to examine the factors that influence outcome. The data of all abdominal aortic aneurysm patients treated with open repair or endovascular aneurysm repair in 2004-2015 were retrospectively retrieved from the clinical database of Tartu University Hospital. The primary endpoint was 30-day, 90-day, and 5-year all-cause mortality. The secondary endpoint was determination of the risk factors for mortality. Elective abdominal aortic aneurysm repair was performed on 228 patients (mean age 71.8 years), of whom 178 (78%) were treated with open repair and 50 (22%) with endovascular aneurysm repair. A total of 48 patients with ruptured abdominal aortic aneurysm were treated with open repair (mean age 73.8 years) at the Department of Vascular Surgery, Tartu University Hospital, Estonia. Mean follow-up period was 4.2 ± 3.3 years. In patients with elective abdominal aortic aneurysm, 30-day, 90-day, and 5-year all-cause mortality rates were 0.9%, 2.6%, and 32%, respectively. In multivariate analysis, the main predictors for 5-year mortality were preoperative creatinine value and age (p < 0.05). In patients with ruptured abdominal aortic aneurysm, 30-day, 90-day, and 5-year all-cause mortality rates were 22.9%, 33.3%, and 55.1%, respectively. In multivariate analysis, the risk factors for 30-day mortality in ruptured abdominal aortic aneurysm were perioperative hemoglobin and lactate levels (p < 0.05). According to this study, the all-cause mortality rates of elective abdominal aortic aneurysm and ruptured abdominal aortic aneurysm at our hospital were comparable to those at other centers worldwide. Even though some variables were identified as potential predictors of survival, the mortality rates after ruptured abdominal aortic aneurysm remain high. Early diagnosis, timely treatment, and detection of the risk factors for abdominal aortic aneurysm progression would improve survival in patients with abdominal aortic aneurysm.

Younger age of menopause in women with cerebral aneurysms.

PubMed

Ding, Christine; Toll, Valerie; Ouyang, Bichun; Chen, Michael

2013-07-01

The incidence of subarachnoid hemorrhage in women surges following menopause. Estrogen fluctuations have been implicated in cerebral aneurysm formation, growth and rupture and are thought to explain the well-known gender disparity. The aim of this study was to examine the association between age at menopause, which can determine lifetime estrogen exposure, and the presence of cerebral aneurysms. A retrospective case-control study was conducted by interviewing postmenopausal women with intradural cerebral aneurysms about their basic medical and gynecologic histories. This information was compared with the same data points collected from 4682 women contacted through random digit phone dialing in the National Institute of Child Health and Human Development-sponsored Contraceptive and Reproductive Experiences Study published in 2002. Among 76 consecutive postmenopausal women with cerebral aneurysms who were treated by a single physician and interviewed, multivariate logistic regression showed that later menopause age (OR 0.79, CI 0.63 to 0.996, p=0.046) was significantly associated with a lower aneurysm incidence. Premature menopause (<40 years) was seen in 26% of cases and 19% of controls (p=0.15). Each categorical increase in menopause age (<40, 40-44, 45-49, 50-54, ≥55 years) decreased the likelihood by 21%. Despite a trend towards earlier mean age at menopause in the case group, the difference was not statistically significant. There is a trend showing that an earlier age at menopause is associated with the presence of a cerebral aneurysm. This suggests that loss of estrogen earlier in a woman's life may contribute to the pathogenesis of cerebral aneurysm. These data may identify a risk factor for cerebral aneurysm pathogenesis and also a potential target for future therapies.

Diffusion-Weighted Imaging-Detected Ischemic Lesions following Endovascular Treatment of Cerebral Aneurysms: A Systematic Review and Meta-Analysis.

PubMed

Bond, K M; Brinjikji, W; Murad, M H; Kallmes, D F; Cloft, H J; Lanzino, G

2017-02-01

Endovascular treatment of intracranial aneurysms is associated with the risk of thromboembolic ischemic complications. Many of these events are asymptomatic and identified only on diffusion-weighted imaging. We performed a systematic review and meta-analysis to study the incidence of DWI positive for thromboembolic events following endovascular treatment of intracranial aneurysms. A comprehensive literature search identified studies published between 2000 and April 2016 that reported postprocedural DWI findings in patients undergoing endovascular treatment of intracranial aneurysms. The primary outcome was the incidence of DWI positive for thromboembolic events. We examined outcomes by treatment type, sex, and aneurysm characteristics. Meta-analyses were performed by using a random-effects model. Twenty-two studies with 2148 patients and 2268 aneurysms were included. The overall incidence of DWI positive for thromboembolic events following endovascular treatment was 49% (95% CI, 42%-56%). Treatment with flow diversion trended toward a higher rate of DWI positive for lesions than coiling alone (67%; 95% CI, 46%-85%; versus 45%; 95% CI, 33%-56%; P = .07). There was no difference between patients treated with coiling alone and those treated with balloon-assisted (44%; 95% CI, 29%-60%; P = .99) or stent-assisted (43%; 95% CI, 24%-63%; P = .89) coiling. Sex, aneurysm rupture status, location, and size were not associated with the rate of DWI positive for lesions. One in 2 patients may have infarcts on DWI following endovascular treatment of intracranial aneurysms. There is a trend toward a higher incidence of DWI-positive lesions following treatment with flow diversion compared with coiling. Patient demographics and aneurysm characteristics were not associated with DWI-positive thromboembolic events. © 2017 by American Journal of Neuroradiology.

The Preinterventional Psychiatric History as a Major Predictor for a Reduced Quality of Life After Treatment of Unruptured Intracranial Aneurysms.

PubMed

Fontana, Johann; Wenz, Ralf; Groden, Christoph; Schmieder, Kirsten; Wenz, Holger

2015-11-01

A significantly increased rate of positive preinterventional psychiatric histories in the unruptured aneurysm collective was demonstrated previously. The current study was designed to analyze the influence of the preinterventional psychiatric status on the outcome after treatment of unruptured intracranial aneurysms. Patients treated due to meningioma World Health Organization °I and unruptured intracranial aneurysms in 2 German neurosurgical centers between 2007 and 2013 were screened for exclusion criteria including malignant/chronic diseases, recurrence of the tumor/aneurysm, and neurologic deficits among others. The preinterventional psychiatric histories and the rates of postinterventional headaches, sleeping disorders, symptoms of chronic fatigue syndrome, and quality of life (QOL) were determined by questionnaires that were mailed to the patients in a printed version. A total of 58 M patients and 45 iA patients who met the inclusion criteria returned the questionnaires; 10 M (17.2%) and 17 iA patients (37.8%) had a positive psychiatric history. The overall Incidental aneurysm collective demonstrated significantly lower overall QOL scores (P = 0.003) and significant greater rates of chronic fatigue syndrome (P = 0.009) compared with the M collective. After we excluded all patients with positive pre-interventional psychiatric histories, those differences were no longer reproducible. Subjectively, the patients did not realize any significant changes in their QOL after successful aneurysm treatment. The results of the current study demonstrate the importance of taking the preinterventional psychiatric history into considerations when evaluating the outcome after unruptured aneurysm treatment. The unfavorable outcome of the aneurysm group seems to be caused by factors that are not related the aneurysm diagnosis or treatment itself. Copyright © 2015 Elsevier Inc. All rights reserved.

Contrast-enhanced time-resolved MRA for follow-up of intracranial aneurysms treated with the pipeline embolization device.

PubMed

Boddu, S R; Tong, F C; Dehkharghani, S; Dion, J E; Saindane, A M

2014-01-01

Endovascular reconstruction and flow diversion by using the Pipeline Embolization Device is an effective treatment for complex cerebral aneurysms. Accurate noninvasive alternatives to DSA for follow-up after Pipeline Embolization Device treatment are desirable. This study evaluated the accuracy of contrast-enhanced time-resolved MRA for this purpose, hypothesizing that contrast-enhanced time-resolved MRA will be comparable with DSA and superior to 3D-TOF MRA. During a 24-month period, 37 Pipeline Embolization Device-treated intracranial aneurysms in 26 patients underwent initial follow-up by using 3D-TOF MRA, contrast-enhanced time-resolved MRA, and DSA. MRA was performed on a 1.5T unit by using 3D-TOF and time-resolved imaging of contrast kinetics. All patients underwent DSA a median of 0 days (range, 0-68) after MRA. Studies were evaluated for aneurysm occlusion, quality of visualization of the reconstructed artery, and measurable luminal diameter of the Pipeline Embolization Device, with DSA used as the reference standard. The sensitivity, specificity, and positive and negative predictive values of contrast-enhanced time-resolved MRA relative to DSA for posttreatment aneurysm occlusion were 96%, 85%, 92%, and 92%. Contrast-enhanced time-resolved MRA demonstrated superior quality of visualization (P = .0001) and a higher measurable luminal diameter (P = .0001) of the reconstructed artery compared with 3D-TOF MRA but no significant difference compared with DSA. Contrast-enhanced time-resolved MRA underestimated the luminal diameter of the reconstructed artery by 0.965 ± 0.497 mm (27% ± 13%) relative to DSA. Contrast-enhanced time-resolved MRA is a reliable noninvasive method for monitoring intracranial aneurysms following flow diversion and vessel reconstruction by using the Pipeline Embolization Device. © 2014 by American Journal of Neuroradiology.

Use of a surgical rehearsal platform and improvement in aneurysm clipping measures: results of a prospective, randomized trial.

PubMed

Chugh, A Jessey; Pace, Jonathan R; Singer, Justin; Tatsuoka, Curtis; Hoffer, Alan; Selman, Warren R; Bambakidis, Nicholas C

2017-03-01

OBJECTIVE The field of neurosurgery is constantly undergoing improvements and advances, both in technique and technology. Cerebrovascular neurosurgery is no exception, with endovascular treatments changing the treatment paradigm. Clipping of aneurysms is still necessary, however, and advances are still being made to improve patient outcomes within the microsurgical treatment of aneurysms. Surgical rehearsal platforms are surgical simulators that offer the opportunity to rehearse a procedure prior to entering the operative suite. This study is designed to determine whether use of a surgical rehearsal platform in aneurysm surgery is helpful in decreasing aneurysm dissection time and clip manipulation of the aneurysm. METHODS The authors conducted a blinded, prospective, randomized study comparing key effort and time variables in aneurysm clip ligation surgery with and without preoperative use of the SuRgical Planner (SRP) surgical rehearsal platform. Initially, 40 patients were randomly assigned to either of two groups: one in which surgery was performed after use of the SRP (SRP group) and one in which surgery was performed without use of the SRP (control group). All operations were videotaped. After exclusion of 6 patients from the SRP group and 9 from the control group, a total of 25 surgical cases were analyzed by a reviewer blinded to group assignment. The videos were analyzed for total microsurgical time, number of clips used, and number of clip placement attempts. Means and standard deviations (SDs) were calculated and compared between groups. RESULTS The mean (± SD) amount of operative time per clip used was 920 ± 770 seconds in the SRP group and 1294 ± 678 seconds in the control group (p = 0.05). In addition, the mean values for the number of clip attempts, total operative time, ratio of clip attempts to clips used, and time per clip attempt were all lower in the SRP group, although the between-group differences were not statistically significant. CONCLUSIONS Preoperative rehearsal with SRP increased efficiency and safety in aneurysm microsurgery as demonstrated by the statistically significant improvement in time per clip used. Although the rest of the outcomes did not demonstrate statistically significant between-group differences, the fact that the SRP group showed improvement in mean values for all measures studied suggests that preoperative rehearsal may increase the efficiency and safety of aneurysm microsurgery. Future studies aimed at improving patient outcome and safety during surgical clipping of aneurysms will be needed to keep pace with the quickly advancing endovascular field.

[Individualized fluid-solid coupled model of intracranial aneurysms based on computed tomography angiography data].

PubMed

Wang, Fuyu; Xu, Bainan; Sun, Zhenghui; Liu, Lei; Wu, Chen; Zhang, Xiaojun

2012-10-01

To establish an individualized fluid-solid coupled model of intracranial aneurysms based on computed tomography angiography (CTA) image data. The original Dicom format image data from a patient with an intracranial aneurysm were imported into Mimics software to construct the 3D model. The fluid-solid coupled model was simulated with ANSYS and CFX software, and the sensitivity of the model was analyzed. The difference between the rigid model and fluid-solid coupled model was also compared. The fluid-solid coupled model of intracranial aneurysm was established successfully, which allowed direct simulation of the blood flow of the intracranial aneurysm and the deformation of the solid wall. The pressure field, stress field, and distribution of Von Mises stress and deformation of the aneurysm could be exported from the model. A small Young's modulus led to an obvious deformation of the vascular wall, and the walls with greater thicknesses had smaller deformations. The rigid model and the fluid-solid coupled model showed more differences in the wall shear stress and blood flow velocity than in pressure. The fluid-solid coupled model more accurately represents the actual condition of the intracranial aneurysm than the rigid model. The results of numerical simulation with the model are reliable to study the origin, growth and rupture of the aneurysms.

CFD and PIV Analysis of Hemodynamics in a Growing Intracranial Aneurysm

PubMed Central

Raschi, Marcelo; Mut, Fernando; Byrne, Greg; Putman, Christopher M.; Tateshima, Satoshi; Viñuela, Fernando; Tanoue, Tetsuya; Tanishita, Kazuo; Cebral, Juan R.

2011-01-01

Hemodynamics is thought to be a fundamental factor in the formation, progression and rupture of cerebral aneurysms. Understanding these mechanisms is important to improve their rupture risk assessment and treatment. In this study we analyze the blood flow field in a growing cerebral aneurysm using experimental particle image velocimetry (PIV) and computational fluid dynamics (CFD) techniques. Patient-specific models were constructed from longitudinal 3D computed tomography angiography (CTA) images acquired at one-year intervals. Physical silicone models were constructed from the CTA images using rapid prototyping techniques and pulsatile flow fields were measured with PIV. Corresponding CFD models were created and run under matching flow conditions. Both flow fields were aligned, interpolated, and compared qualitatively by inspection and quantitatively by defining similarity measures between the PIV and CFD vector fields. Results showed that both flow fields were in good agreement. Specifically, both techniques provided consistent representations of the main intra-aneurysmal flow structures, and their change during the geometric evolution of the aneurysm. Despite differences observed mainly in the near wall region and the inherent limitations of each technique, the information derived is consistent and can be used to study the role of hemodynamics in the natural history of intracranial aneurysms. PMID:22548127

Modeling of the aorta artery aneurysms and renal artery stenosis using cardiovascular electronic system

PubMed Central

Hassani, Kamran; Navidbakhsh, Mahdi; Rostami, Mostafa

2007-01-01

Background The aortic aneurysm is a dilatation of the aortic wall which occurs in the saccular and fusiform types. The aortic aneurysms can rupture, if left untreated. The renal stenosis occurs when the flow of blood from the arteries leading to the kidneys is constricted by atherosclerotic plaque. This narrowing may lead to the renal failure. Previous works have shown that, modelling is a useful tool for understanding of cardiovascular system functioning and pathophysiology of the system. The present study is concerned with the modelling of aortic aneurysms and renal artery stenosis using the cardiovascular electronic system. Methods The geometrical models of the aortic aneurysms and renal artery stenosis, with different rates, were constructed based on the original anatomical data. The pressure drop of each section due to the aneurysms or stenosis was computed by means of computational fluid dynamics method. The compliance of each section with the aneurysms or stenosis is also calculated using the mathematical method. An electrical system representing the cardiovascular circulation was used to study the effects of these pressure drops and the compliance variations on this system. Results The results showed the decreasing of pressure along the aorta and renal arteries lengths, due to the aneurysms and stenosis, at the peak systole. The mathematical method demonstrated that compliances of the aorta sections and renal increased with the expansion rate of the aneurysms and stenosis. The results of the modelling, such as electrical pressure graphs, exhibited the features of the pathologies such as hypertension and were compared with the relevant experimental data. Conclusion We conclude from the study that the aortic aneurysms as well as renal artery stenosis may be the most important determinant of the arteries rupture and failure. Furthermore, these pathologies play important rules in increase of the cardiovascular pulse pressure which leads to the hypertension. PMID:17559685

Automatic aneurysm neck detection using surface Voronoi diagrams.

PubMed

Cárdenes, Rubén; Pozo, José María; Bogunovic, Hrvoje; Larrabide, Ignacio; Frangi, Alejandro F

2011-10-01

A new automatic approach for saccular intracranial aneurysm isolation is proposed in this work. Due to the inter- and intra-observer variability in manual delineation of the aneurysm neck, a definition based on a minimum cost path around the aneurysm sac is proposed that copes with this variability and is able to make consistent measurements along different data sets, as well as to automate and speedup the analysis of cerebral aneurysms. The method is based on the computation of a minimal path along a scalar field obtained on the vessel surface, to find the aneurysm neck in a robust and fast manner. The computation of the scalar field on the surface is obtained using a fast marching approach with a speed function based on the exponential of the distance from the centerline bifurcation between the aneurysm dome and the parent vessels. In order to assure a correct topology of the aneurysm sac, the neck computation is constrained to a region defined by a surface Voronoi diagram obtained from the branches of the vessel centerline. We validate this method comparing our results in 26 real cases with manual aneurysm isolation obtained using a cut-plane, and also with results obtained using manual delineations from three different observers by comparing typical morphological measures. © 2011 IEEE

The 25th anniversary of the retrograde suction decompression technique (Dallas technique) for the surgical management of paraclinoid aneurysms: historical background, systematic review, and pooled analysis of the literature.

PubMed

Flores, Bruno C; White, Jonathan A; Batjer, H Hunt; Samson, Duke S

2018-05-04

OBJECTIVE Paraclinoid internal carotid artery (ICA) aneurysms frequently require temporary occlusion to facilitate safe clipping. Brisk retrograde flow through the ophthalmic artery and cavernous ICA branches make simple trapping inadequate to soften the aneurysm. The retrograde suction decompression (RSD), or Dallas RSD, technique was described in 1990 in an attempt to overcome some of those treatment limitations. A frequent criticism of the RSD technique is an allegedly high risk of cervical ICA dissection. An endovascular modification was introduced in 1991 (endovascular RSD) but no studies have compared the 2 RSD variations. METHODS The authors performed a systematic review of MEDLINE/PubMed and Web of Science and identified all studies from 1990-2016 in which either Dallas RSD or endovascular RSD was used for treatment of paraclinoid aneurysms. A pooled analysis of the data was completed to identify important demographic and treatment-specific variables. The primary outcome measure was defined as successful aneurysm obliteration. Secondary outcome variables were divided into overall and RSD-specific morbidity and mortality rates. RESULTS Twenty-six RSD studies met the inclusion criteria (525 patients, 78.9% female). The mean patient age was 53.5 years. Most aneurysms were unruptured (56.6%) and giant (49%). The most common presentations were subarachnoid hemorrhage (43.6%) and vision changes (25.3%). The aneurysm obliteration rate was 95%. The mean temporary occlusion time was 12.7 minutes. Transient or permanent morbidity was seen in 19.9% of the patients. The RSD-specific complication rate was low (1.3%). The overall mortality rate was 4.2%, with 2 deaths (0.4%) attributable to the RSD technique itself. Good or fair outcome were reported in 90.7% of the patients. Aneurysm obliteration rates were similar in the 2 subgroups (Dallas RSD 94.3%, endovascular RSD 96.3%, p = 0.33). Despite a higher frequency of complex (giant or ruptured) aneurysms, Dallas RSD was associated with lower RSD-related morbidity (0.6% vs 2.9%, p = 0.03), compared with the endovascular RSD subgroup. There was a trend toward higher mortality in the endovascular RSD subgroup (6.4% vs 3.1%, p = 0.08). The proportion of patients with poor neurological outcome at last follow-up was significantly higher in the endovascular RSD group (15.4% vs 7.2%, p < 0.01). CONCLUSIONS The treatment of paraclinoid ICA aneurysms using the RSD technique is associated with high aneurysm obliteration rates, good long-term neurological outcome, and low RSD-related morbidity and mortality. Review of the RSD literature showed no evidence of a higher complication rate associated with the Dallas technique compared with similar endovascular methods. On a subgroup analysis of Dallas RSD and endovascular RSD, both groups achieved similar obliteration rates, but a lower RSD-related morbidity was seen in the Dallas technique subgroup. Twenty-five years after its initial publication, RSD remains a useful neurosurgical technique for the management of large and giant paraclinoid aneurysms.

Role of MRA in the detection of intracranial aneurysm in the acute phase of subarachnoid hemorrhage.

PubMed

Pierot, Laurent; Portefaix, Christophe; Rodriguez-Régent, Christine; Gallas, Sophie; Meder, Jean-François; Oppenheim, Catherine

2013-07-01

Magnetic resonance angiography (MRA) has been evaluated for the detection of unruptured intracranial aneurysms with favorable results at 3 Tesla (3T) and with similar diagnostic accuracy as both 3D time-of-flight (3D-TOF) and contrast-enhanced (CE-MRA) MRA. However, the diagnostic value and place of MRA in the detection of ruptured aneurysms has been little evaluated. Thus, the goal of this prospective single-center series was to assess the feasibility and diagnostic value of 3T 3D-TOF MRA and CE-MRA for aneurysm detection in acute non-traumatic subarachnoid hemorrhage (SAH). From March 2006 to December 2007, all consecutive patients admitted to our hospital with acute non-traumatic SAH (≤10 days) were prospectively included in this study evaluating MRA in the diagnostic workup of SAH. Feasibility of MRA and sensitivity/specificity of 3D-TOF and CE-MRA were assessed compared with gold standard DSA. In all, 84 consecutive patients (45 women, 39 men; age 23-86 years) were included. The feasibility of MRA was low (43/84, 51.2%). The reasons given for patients not undergoing magnetic resonance imaging (MRI) examination were clinical status (27 patients), potential delay in aneurysm treatment (11 patients) and contraindications to MRI (three patients). In patients explored by MRA, the sensitivity of CE-MRA (95%) was higher compared with 3D-TOF (86%) with similar specificity (80%). Also, 3D-TOF missed five aneurysms while CE-MRA missed two. The value of MRA in the diagnostic workup of ruptured aneurysms is limited due to its low feasibility during the acute phase of bleeding. Sensitivity for aneurysm detection was good for both MRA techniques, but tended to be better with CE-MRA. Copyright © 2013. Published by Elsevier Masson SAS.

Wall enhancement on high-resolution magnetic resonance imaging may predict an unsteady state of an intracranial saccular aneurysm.

PubMed

Hu, Peng; Yang, Qi; Wang, Dan-Dan; Guan, Shao-Chen; Zhang, Hong-Qi

2016-10-01

The aneurysm wall has been reported to play a critical role in the formation, development, and even rupture of an aneurysm. We used high-resolution magnetic resonance imaging (HRMRI) to investigate the aneurysm wall in an effort to identify evidence of inflammation invasion and define its relationship with aneurysm behavior. Patients with intracranial aneurysms who were prospectively evaluated using HRMRI between July 2013 and June 2014 were enrolled in this study. The aneurysm's wall enhancement and evidence of inflammation invasion were determined. In addition, the relationship between aneurysm wall enhancement and aneurysm size and symptoms, including ruptured aneurysms, giant unruputred intracranial aneurysms (UIAs) presenting as mass effect, progressively growing aneurysms, and aneurysms associated with neurological symptoms, was statistically analyzed. Twenty-five patients with 30 aneurysms were available for the current study. Fourteen aneurysms showed wall enhancement, including 6 ruptured and 8 unruptured aneurysms. Evidence of inflammation was identified directly through histological studies and indirectly through intraoperative investigations and clinical courses. The statistical analysis indicated no significant correlation between aneurysm wall enhancement and aneurysm size. However, there was a strong correlation between wall enhancement and aneurysm symptoms, with a kappa value of 0.86 (95 % CI 0.68-1). Aneurysm wall enhancement on HRMRI might be a sign of inflammatory change. Symptomatic aneurysms exhibited wall enhancement on HRMRI. Wall enhancement had a high consistent correlation of symptomatic aneurysms. Therefore, wall enhancement on HRMRI might predict an unsteady state of an intracranial saccular aneurysm.

Rabbit aortic aneurysm model with enlarging diameter capable of better mimicking human aortic aneurysm disease.

PubMed

Bi, Yonghua; Chen, Hongmei; Li, Yahua; Yu, Zepeng; Han, Xinwei; Ren, Jianzhuang

2018-01-01

The self-healing phenomenon can be found in the elastase-induced abdominal aortic aneurysm (AAA) model, and an enlarging AAA model was successfully induced by coarctation. Unfortunately, aortic coarctation in these enlarging models is generally not found in human AAA disease. This study aimed to create an experiment model of enlarging AAA in rabbits to better mimic human aortic aneurysm disease. Eighty-four male New Zealand white rabbits were randomly divided into three equal groups: two aneurysm groups (A and B) and a SHAM group. Aneurysm group rabbits underwent extrinsic aortic stenosis below the right renal artery and received a 10-minute incubation of 60 μl elastase (1 unit/μl). Absorbable suture was used in Group A and nonabsorbable cotton thread was used in Group B. A sham operation was performed in the SHAM group. Aortic diameter was measured after 1, 3, 7, and 15 weeks; thereafter animals were sacrificed for histopathological, immunohistochemical and quantitative studies. Two rabbits died at 29 and 48 days, respectively, after operation in Group B. All aneurysms formed and enlarged progressively by 3 weeks in the Aneurysm groups. However, diameter enlargement in Group A was significantly lower than that in Group B at 7 weeks. Aneurysm groups developed intimal hyperplasia; intima-media thickness (IMT) increased significantly by week 7, and aortic media thickness and intima-media ratio (IMR) increased significantly by week 15. Marked destruction of elastin fibers and smooth muscle cells (SMCs) occurred 1 week later and increased progressively thereafter. Intimal hyperplasia and SMCs content in Group A increased significantly by week 15 compared with Group B. Aneurysm groups exhibited strong expression of matrix metalloproteinases 2 and 9 and RAM11 by week 1, and decreased progressively thereafter. In conclusion, this novel rabbit AAA model enlarges progressively without coarctation and is capable of better mimicking human aortic aneurysm disease.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pitton, Michael Bernhard, E-mail: pitton@radiologie.klinik.uni-mainz.de; Schmenger, Patrick; Dueber, Christoph

Purpose: To investigate pressure and maximum rate of rise of systolic pressure (peak dP/dt) in completely excluded aneurysms and endoleaks to determine the hemodynamic impact of endoleaks. Methods: In mongrel dogs (n =36) experimental aneurysms were created by insertion of a patch (portion of rectus abdomen is muscle sheath) into the infrarenalaorta. In group I (n 18), all aortic branches of the aneurysm were ligated and all aneurysms were completely excluded by stent grafts. Group II (n = 18) consisted of aneurysms with patent aortic side branches that represented sources of endoleaks.One week (n = 12), six weeks (n =more » 12),and six months (n = 12) after stent grafting,hemodynamic measurements were obtained in thrombosed aneurysms and proved endoleaks. Systemic blood pressure and intraaneurysmal pressure were simultaneously measured and the respective peak dP/dt were computed. Results: At the six-month follow-up, the systolic-pressure ratio (intraaneurysmatic pressure: systemic pressure)was significantly increased in endoleaks compared to non-perfused areas(0.879 {+-} 0.042 versus 0.438 {+-} 0.176, p <0.01, group II) or completely excluded aneurysms (0.385 {+-}0.221, group I). Peak dP/dt ratio (intraaneurysmal peak dP/dt: systemic peak dP/dt) was 0.922 {+-} 0.154 in endoleaks, compared to 0.084 {+-} 0.080 in non-perfused areas (group II, p <0.01), and was 0.146 {+-} 0.121 in completely excluded aneurysms (group I). The diastolic-pressure ratio was also increased inendoleaks compared to non-perfused areas (0.929 {+-} 0.088 versus 0.655 {+-} 0.231, p < 0.01, group II) or completely excluded aneurysms (0.641 {+-} 0.278, group I). In excluded aneurysms, pressure exposure declined as the length of the follow-up period increased. Conclusion: Type II endoleaks transmit pulsatile pressure of near systemic level and indicate insufficient treatment result. In contrast, complete endovascular exclusion of aneurysms results in significantly reduced pressure exposure.« less

In vitro study of near-wall flow in a cerebral aneurysm model with and without coils.

PubMed

Goubergrits, L; Thamsen, B; Berthe, A; Poethke, J; Kertzscher, U; Affeld, K; Petz, C; Hege, H-C; Hoch, H; Spuler, A

2010-09-01

Coil embolization procedures change the flow conditions in the cerebral aneurysm and, therefore, in the near-wall region. Knowledge of these flow changes may be helpful to optimize therapy. The goal of this study was to investigate the effect of the coil-packing attenuation on the near-wall flow and its variability due to differences in the coil structure. An enlarged transparent model of an ACA aneurysm was fabricated on the basis of CT angiography. The near-wall flow was visualized by using a recently proposed technique called Wall-PIV. Coil-packing attenuation of 10%, 15%, and 20% were investigated and compared with an aneurysmal flow without coils. Then the flow variability due to the coil introduction was analyzed in 10 experiments by using a packing attenuation of 15%. A small packing attenuation of 10% already alters the near-wall flow significantly in a large part of the aneurysmal sac. These flow changes are characterized by a slow flow with short (interrupted) path lines. An increased packing attenuation expands the wall area exposed to the altered flow conditions. This area, however, depends on the coil position and/or on the 3D coil structure in the aneurysm. To our knowledge, this is the first time the near-wall flow changes caused by coils in an aneurysm model have been visualized. It can be concluded that future hydrodynamic studies of coil therapy should include an investigation of the coil structure in addition to the coil-packing attenuation.

Successful Retreatment of Recurrent Intracranial Vertebral Artery Dissecting Aneurysms After Stent-Assisted Coil Embolization: A Self-Controlled Hemodynamic Analysis.

PubMed

Liu, Jian; Jing, Linkai; Zhang, Ying; Song, Ying; Wang, Yang; Li, Chuanhui; Wang, Yanmin; Mu, Shiqing; Paliwal, Nikhil; Meng, Hui; Linfante, Italo; Yang, Xinjian

2017-01-01

Intracranial vertebral artery dissecting aneurysms (VADAs) tend to recur despite successful stent-assisted coil embolization (SACE). Hemodynamics is useful in evaluating aneurysmal formation, growth, and rupture. Our aim was to evaluate the hemodynamic patterns of the recurrence of VADA. Between September 2009 and November 2013, all consecutive patients with recurrent VADAs after SACE in our institutions were enrolled. Recurrence was defined as recanalization and/or regrowth. We assessed the hemodynamic alterations in wall shear stress (WSS) and velocity after the initial SACE and subsequently after retreatment of the aneurysms that recurred. Five patients were included. After the initial treatment, 3 patients showed recanalization and 2 showed regrowth. In the 2 patients with regrowth, the 2 original aneurysms maintained complete occlusion; however, de novo aneurysm regrowth was confirmed near the previous site. Compared with 3 recanalized aneurysms, the completely occluded aneurysms showed high mean reductions in velocity and WSS after initial treatment (velocity, 77.6% vs. 57.7%; WSS, 74.2% vs. 52.4%); however, WSS remained high at the region near the previous lesion where the new aneurysm originated. After the second retreatment, there was no recurrence in any patient. Compared with the 3 aneurysms that recanalized, the 4 aneurysms that maintained complete occlusion showed higher reductions in velocity (62.9%) and WSS (71.1%). Our series indicated that hemodynamics might have an important role in recurrence of VADAs. After endovascular treatment, sufficient hemodynamic reduction in aneurysm dome, orifice, and parent vessel may be one of the key factors for preventing recurrence in VADAs. Copyright © 2016 Elsevier Inc. All rights reserved.

Size ratio correlates with intracranial aneurysm rupture status: a prospective study.

PubMed

Rahman, Maryam; Smietana, Janel; Hauck, Erik; Hoh, Brian; Hopkins, Nick; Siddiqui, Adnan; Levy, Elad I; Meng, Hui; Mocco, J

2010-05-01

The prediction of intracranial aneurysm (IA) rupture risk has generated significant controversy. The findings of the International Study of Unruptured Intracranial Aneurysms (ISUIA) that small anterior circulation aneurysms (<7 mm) have a 0% risk of subarachnoid hemorrhage in 5 years is difficult to reconcile with other studies that reported a significant portion of ruptured IAs are small. These discrepancies have led to the search for better aneurysm parameters to predict rupture. We previously reported that size ratio (SR), IA size divided by parent vessel diameter, correlated strongly with IA rupture status (ruptured versus unruptured). These data were all collected retrospectively off 3-dimensional angiographic images. Therefore, we performed a blinded prospective collection and evaluation of SR data from 2-dimensional angiographic images for a consecutive series of patients with ruptured and unruptured IAs. We prospectively enrolled 40 consecutive patients presenting to a single institution with either ruptured IA or for first-time evaluation of an incidental IA. Blinded technologists acquired all measurements from 2-dimensional angiographic images. Aneurysm rupture status, location, IA maximum size, and parent vessel diameter were documented. The SR was calculated by dividing the aneurysm size (mm) by the average parent vessel size (mm). A 2-tailed Mann-Whitney test was performed to assess statistical significance between ruptured and unruptured groups. Fisher exact test was used to compare medical comorbidities between the ruptured and unruptured groups. Significant differences between the 2 groups were subsequently tested with logistic regression. SE and probability values are reported. Forty consecutive patients with 24 unruptured and 16 ruptured aneurysms met the inclusion criteria. No significant differences were found in age, gender, smoking status, or medical comorbidities between ruptured and unruptured groups. The average maximum size of the unruptured IAs (6.18 + or - 0.60 mm) was significantly smaller compared with the ruptured IAs (7.91 + or - 0.47 mm; P=0.03), and the unruptured group had significantly smaller SRs (2.57 + or - 0.24 mm) compared with the ruptured group (4.08 + or - 0.54 mm; P<0.01). Logistic regression was used to evaluate the independent predictive value of those variables that achieved significance in univariate analysis (IA maximum size and SR). Using stepwise selection, only SR remained in the final predictive model (OR, 2.12; 95% CI, 1.09 to 4.13). SR, the ratio between aneurysm size and parent artery diameter, can be easily calculated from 2-dimensional angiograms and correlates with IA rupture status on presentation in a blinded analysis. SR should be further studied in a large prospective observational cohort to predict true IA risk of rupture.

Plasma D-dimer as a predictor of the progression of abdominal aortic aneurysm.

PubMed

Vele, E; Kurtcehajic, A; Zerem, E; Maskovic, J; Alibegovic, E; Hujdurovic, A

2016-11-01

Essentials D-dimer could provide important information about abdominal aortic aneurysm (AAA) progression. The greatest diameter of the infrarenal aorta and the value of plasma D-dimer were determined. AAA progression is correlated with increasing plasma D-dimer levels. The increasing value of plasma D-dimer could be a predictor of aneurysm progression. Background The natural course of abdominal aortic aneurysm (AAA) is mostly asymptomatic and unpredictable. D-dimer could provide potentially important information about subsequent AAA progression. Objectives The aims of this study were to establish the relationship between the progression of an abdominal aortic aneurysm (AAA) and plasma D-dimer concentration over a 12-month period and determine the value of plasma D-dimer in patients with sub-aneurysmal aortic dilatation. Patients/Methods This was a prospective observational study that involved 33 patients with an AAA, 30 patients with sub-aneurysmal aortic dilatation and 30 control subjects. The greatest diameter of the infrarenal aorta, which was assessed by ultrasound, and the value of plasma D-dimer were determined for all subjects at baseline assessment, as well as after 12 months for those with an AAA. Results A positive correlation was found between the diameter of an AAA and plasma D-dimer concentration at the baseline and the control measurement stages. There was a strong positive correlation between AAA progression and increasing plasma D-dimer concentration over a 12-month period. Among patients with sub-aneurysmal aortic dilatation (n = 30), the value of plasma D-dimer was higher compared with matched controls (n = 30). Conclusions There is a strongly positive correlation between AAA progression and increasing plasma D-dimer concentration. The value of plasma D-dimer is higher in patients with sub-aneurysmal aortic dilatation than in control subjects. © 2016 International Society on Thrombosis and Haemostasis.

Virtual Cerebral Aneurysm Clipping with Real-Time Haptic Force Feedback in Neurosurgical Education.

PubMed

Gmeiner, Matthias; Dirnberger, Johannes; Fenz, Wolfgang; Gollwitzer, Maria; Wurm, Gabriele; Trenkler, Johannes; Gruber, Andreas

2018-04-01

Realistic, safe, and efficient modalities for simulation-based training are highly warranted to enhance the quality of surgical education, and they should be incorporated in resident training. The aim of this study was to develop a patient-specific virtual cerebral aneurysm-clipping simulator with haptic force feedback and real-time deformation of the aneurysm and vessels. A prototype simulator was developed from 2012 to 2016. Evaluation of virtual clipping by blood flow simulation was integrated in this software, and the prototype was evaluated by 18 neurosurgeons. In 4 patients with different medial cerebral artery aneurysms, virtual clipping was performed after real-life surgery, and surgical results were compared regarding clip application, surgical trajectory, and blood flow. After head positioning and craniotomy, bimanual virtual aneurysm clipping with an original forceps was performed. Blood flow simulation demonstrated residual aneurysm filling or branch stenosis. The simulator improved anatomic understanding for 89% of neurosurgeons. Simulation of head positioning and craniotomy was considered realistic by 89% and 94% of users, respectively. Most participants agreed that this simulator should be integrated into neurosurgical education (94%). Our illustrative cases demonstrated that virtual aneurysm surgery was possible using the same trajectory as in real-life cases. Both virtual clipping and blood flow simulation were realistic in broad-based but not calcified aneurysms. Virtual clipping of a calcified aneurysm could be performed using the same surgical trajectory, but not the same clip type. We have successfully developed a virtual aneurysm-clipping simulator. Next, we will prospectively evaluate this device for surgical procedure planning and education. Copyright © 2018 Elsevier Inc. All rights reserved.

Heterogeneous histomorphology, yet homogeneous vascular smooth muscle cell dedifferentiation, characterize human aneurysm disease.

PubMed

Busch, Albert; Hartmann, Elena; Grimm, Caroline; Ergün, Süleyman; Kickuth, Ralph; Otto, Christoph; Kellersmann, Richard; Lorenz, Udo

2017-11-01

Abdominal aortic aneurysm (AAA) is a frequent, potentially life-threatening, disease that can only be treated by surgical means such as open surgery or endovascular repair. No alternative treatment is currently available, and despite expanding knowledge about the pathomechanism, clinical trials on medical aneurysm abrogation have led to inconclusive results. The heterogeneity of human AAA based on histologic examination is thereby generally neglected. In this study we aimed to further elucidate the role of these differences in aneurysm disease. Tissue samples from AAA and popliteal artery aneurysm patients were examined by histomorphologic analysis, immunohistochemistry, Western blot, and polymerase chain reaction. The results were correlated with clinical data such as aneurysm diameter and laboratory results. The morphology of human AAA vessel wall probes varies tremendously based on the grade of inflammation. This correlates with increasing intima/media thickness and upregulation of the vascular endothelial growth factor cascade but not with any clinical parameter or the aneurysm diameter. The phenotypic switch of vascular smooth muscle cells occurred regardless of the inflammatory state and expressional changes of the transcription factors Kruppel-like factor-4 and transforming growth factor-β lead to differential protein localization in aneurysmal compared with control arteries. These changes were in similar manner also observed in samples from popliteal artery aneurysms, which, however, showed a more homogenous phenotype. Heterogeneity of AAA vessel walls based on inflammatory morphology does not correlate with AAA diameter yet harbors specific implications for basic research and possible aneurysm detection. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Gender differences in abdominal aortic aneurysm therapy - a systematic review.

PubMed

Stoberock, Konstanze; Kölbel, Tilo; Atlihan, Gülsen; Debus, Eike Sebastian; Tsilimparis, Nikolaos; Larena-Avellaneda, Axel; Behrendt, Christian Alexander; Wipper, Sabine

2018-06-01

This article analyses if and to what extent gender differences exist in abdominal aortic aneurysm (AAA) therapy. For this purpose Medline (PubMed) was searched from January 1999 to January 2018. Keywords were: "abdominal aortic aneurysm", "gender", "prevalence", "EVAR", and "open surgery of abdominal aortic aneurysm". Regardless of open or endovascular treatment of abdominal aortic aneurysms, women have a higher rate of complications and longer hospitalizations compared to men. The majority of studies showed that women have a lower survival rate for surgical and endovascular treatment of abdominal aneurysms after both elective and emergency interventions. Women receive less surgical/interventional and protective medical treatment. Women seem to have a higher risk of rupture, a lower survival rate in AAA, and a higher rate of complications, regardless of endovascular or open treatment. The gender differences may be due to a higher age of women at diagnosis and therapy associated with higher comorbidity, but also because of genetic, hormonal, anatomical, biological, and socio-cultural differences. Strategies for treatment in female patients must be further defined to optimize outcome.

Expression of miR-146a-5p in patients with intracranial aneurysms and its association with prognosis.

PubMed

Zhang, H-L; Li, L; Cheng, C-J; Sun, X-C

2018-02-01

The study aims to detect the association of miR-146a-5p with intracranial aneurysms (IAs). The expression of miR-146a-5p was compared from plasma samples between 72 patients with intracranial aneurysms (IAs) and 40 healthy volunteers by quantitative Real-time polymerase chain reaction (qRT-PCR). Statistical analysis was performed to analyze the relationship between miR-146a-5p expression and clinical data and overall survival (OS) time of IAs patients. Univariate and multivariate Cox proportional hazards have also been performed. Notably, higher miR-146a-5p expression was found in plasma samples from 72 patients with intracranial aneurysms (IAs) compared with 40 healthy controls. Higher miR-146a-5p expression was significantly associated with rupture and Hunt-Hess level in IAs patients. Kaplan-Meier survival analysis verified that higher miR-146a-5p expression predicted a shorter overall survival (OS) compared with lower miR-146a-5p expression in IAs patients. Univariate and multivariate Cox proportional hazards demonstrated that higher miR-146a-5p expression, rupture, and Hunt-Hess were independent risk factors of OS in patients with intracranial aneurysms (IAs). MiR-146a-5p expression may serve as a biomarker for predicting prognosis in patients with IAs.

Abdominal aortic aneurysm and the association with serum levels of Homocysteine, vitamins B6, B12 and Folate

PubMed Central

Lindqvist, Markus; Hellström, Anders; Henriksson, Anders E

2012-01-01

Previous investigations have shown hyperhomocysteinemi in patients with abdominal aortic aneurysm (AAA). In the present study we evaluated the circulating level of homocysteine (Hcy) in relation to renal function, vitamins B6, B12 and folate status in AAA patients with special regard to aneurysm size, and rupture. Hcy, Creatinine, B6, B12 and folate were measured in 119 patients with AAA and 36 controls without aneurysm matched by age, gender and smoking habit. As expected there was a weak correlation between Hcy and vitamins B6, B12 or folate. We found similar levels of Hcy, B6 and folic acid in patients with nonruptured AAA compared to the control group matched by age, gender and smoking habit. There was no correlation between maximum diameter of the nonruptured AAA (n=78) and Hcy, B6 or folate. However, the present study shows a significant inverse correlation between maximum diameter of the nonruptured AAA (n=78) and B12 (r = -0.304, p=0.007) with significant higher levels in small AAA compared to large AAA. In conclusion, Hcy does not seem to be a useful biomarker in AAA disease. The unexpected finding of B12 levels correlating to aneurysm diameter warrants urgent further investigation of B12 supplement to prevent progression of small AAA. PMID:23173106

Abdominal aortic aneurysm and the association with serum levels of Homocysteine, vitamins B6, B12 and Folate.

PubMed

Lindqvist, Markus; Hellström, Anders; Henriksson, Anders E

2012-01-01

Previous investigations have shown hyperhomocysteinemi in patients with abdominal aortic aneurysm (AAA). In the present study we evaluated the circulating level of homocysteine (Hcy) in relation to renal function, vitamins B6, B12 and folate status in AAA patients with special regard to aneurysm size, and rupture. Hcy, Creatinine, B6, B12 and folate were measured in 119 patients with AAA and 36 controls without aneurysm matched by age, gender and smoking habit. As expected there was a weak correlation between Hcy and vitamins B6, B12 or folate. We found similar levels of Hcy, B6 and folic acid in patients with nonruptured AAA compared to the control group matched by age, gender and smoking habit. There was no correlation between maximum diameter of the nonruptured AAA (n=78) and Hcy, B6 or folate. However, the present study shows a significant inverse correlation between maximum diameter of the nonruptured AAA (n=78) and B12 (r = -0.304, p=0.007) with significant higher levels in small AAA compared to large AAA. In conclusion, Hcy does not seem to be a useful biomarker in AAA disease. The unexpected finding of B12 levels correlating to aneurysm diameter warrants urgent further investigation of B12 supplement to prevent progression of small AAA.

Aneurysm Morphology and Prediction of Rupture: An International Study of Unruptured Intracranial Aneurysms Analysis.

PubMed

Mocco, J; Brown, Robert D; Torner, James C; Capuano, Ana W; Fargen, Kyle M; Raghavan, Madhavan L; Piepgras, David G; Meissner, Irene; Huston, John

2018-04-01

There are conflicting data between natural history studies suggesting a very low risk of rupture for small, unruptured intracranial aneurysms and retrospective studies that have identified a much higher frequency of small, ruptured aneurysms than expected. To use the prospective International Study of Unruptured Intracranial Aneurysms cohort to identify morphological characteristics predictive of unruptured intracranial aneurysm rupture. A case-control design was used to analyze morphological characteristics associated with aneurysm rupture in the International Study of Unruptured Intracranial Aneurysms database. Fifty-seven patients with ruptured aneurysms during follow-up were matched (by size and location) with 198 patients with unruptured intracranial aneurysms without rupture during follow-up. Twelve morphological metrics were measured from cerebral angiograms in a blinded fashion. Perpendicular height (P = .008) and size ratio (ratio of maximum diameter to the parent vessel diameter; P = .01) were predictors of aneurysm rupture on univariate analysis. Aspect ratio, daughter sacs, multiple lobes, aneurysm angle, neck diameter, parent vessel diameter, and calculated aneurysm volume were not statistically significant predictors of rupture. On multivariate analysis, perpendicular height was the only significant predictor of rupture (Chi-square 7.1, P-value .008). This study underscores the importance of other morphological factors, such as perpendicular height and size ratio, that may influence unruptured intracranial aneurysm rupture risk in addition to greatest diameter and anterior vs posterior location.

Focused opening of the sylvian fissure for microsurgical management of MCA aneurysms.

PubMed

Elsharkawy, Ahmed; Niemelä, Mika; Lehečka, Martin; Lehto, Hanna; Jahromi, Behnam Rezai; Goehre, Felix; Kivisaari, Riku; Hernesniemi, Juha

2014-01-01

A wide sylvian opening, with either a proximal or distal start, has been standard for microsurgical management of middle cerebral artery (MCA) aneurysms. However, extensive sylvian dissection is potentially associated with increased incidence of iatrogenic injury to the brain and neurovascular structures. The aim of the present study was to describe the technique of focused opening of the sylvian fissure for microsurgical management of MCA aneurysms with additional tips on handling difficulties which may be encountered with this technique. A 3D image-based anatomic orientation, clipping field-focused surgical planning, slack brain, and high magnification are the basic requirements for this approach. A 10-15 mm sylvian opening is placed so that it allows safe access and a good surgical view of the MCA aneurysm clipping field. Under proximal control of the MCA, the aneurysm neck can be dissected and clipped effectively and safely, in this small surgical field. The presented technique has been developed and refined by the senior author during the surgery of 1,097 aneurysms over the last 13 years. It has proved to be safe, and effective for clipping of both ruptured and unruptured MCA aneurysms. Its greatest advantages are a shorter operative time and less brain and vessel manipulation compared to more extensive approaches. The focused sylvian opening is a less-invasive alternative to the classical wide sylvian opening for the microsurgical management of most MCA aneurysms.

Relationship between aneurysm wall enhancement and conventional risk factors in patients with unruptured intracranial aneurysms: A black-blood MRI study.

PubMed

Liu, Peng; Qi, Haikun; Liu, Aihua; Lv, Xianli; Jiang, Yuhua; Zhao, Xihai; Li, Rui; Lu, Bing; Lv, Ming; Chen, Huijun; Li, Youxiang

2016-10-01

Aneurysmal wall enhancement (AWE) has emerged as a new possible biomarker for depicting inflammation of the intracranial aneurysm (IA). However, the relationships of AWE with other risk factors are still unclear for unruptured IA. The purpose of this study was to investigate the association between AWE and other risk metrics. Forty-eight patients with unruptured saccular IAs diagnosed by digital subtraction angiography were recruited to undergo magnetic resonance (MR) black-blood imaging. AWE was evaluated using the pre- and post-contrast black-blood MR images. Univariate and multivariate logistic regression analysis was performed to investigate the association of AWE with other risk factors, including size, maximal neck width, parent vessel diameter, location, multiplicity, daughter sacs and other clinical factors. The prevalence of AWE in each ISUIA grade was reported and compared by Wilcoxon rank sum test. In total, 61 aneurysms were detected in 48 patients. Aneurysm size was found to be an independent risk factor associated with AWE (OR 2.46 per mm increase, 95% CI 1.34-4.51; p = 0.004). Patient age was independently and inversely associated with AWE (OR 0.898 per year increase, 95% CI 0.812-0.994; p = 0.037). Higher prevalence of AWE was observed in larger aneurysms (12%, 71.4%, 100%, and 100% of ISUIA grade 1-4 IAs have AWE, respectively). Notably, 12% of small IAs (size <7 mm) exhibited AWE. The IAs with AWE had significant higher ISUIA grade than the IAs without (p < 0.001, Wilcoxon rank sum test). The wall enhancement in contrast-enhanced black-blood MR images was independently associated with aneurysm size in unruptured IAs. However, some small unruptured aneurysms did exhibit wall enhancement, suggesting that AWE may provide additional aneurysm instability information to improve current size-based rupture risk evaluation metrics. © The Author(s) 2016.

Magnesium alloy covered stent for treatment of a lateral aneurysm model in rabbit common carotid artery: An in vivo study

NASA Astrophysics Data System (ADS)

Wang, Wu; Wang, Yong-Li; Chen, Mo; Chen, Liang; Zhang, Jian; Li, Yong-Dong; Li, Ming-Hua; Yuan, Guang-Yin

2016-11-01

Magnesium alloy covered stents have rarely been used in the common carotid artery (CCA). We evaluated the long-term efficacy of magnesium alloy covered stents in a lateral aneurysm model in rabbit CCA. Magnesium alloy covered stents (group A, n = 7) or Willis covered stents (group B, n = 5) were inserted in 12 New Zealand White rabbits and they were followed up for 12 months. The long-term feasibility for aneurysm occlusion was studied through angiograms; the changes in vessel area and lumen area were assessed with IVUS. Complete aneurysmal occlusion was achieved in all aneurysms. Angiography showed that the diameter of the stented CCA in group A at 6 and 12 months was significantly greater than the diameter immediately after stent placement. On intravascular ultrasound (IVUS) examination, the mean lumen area of the stented CCA in group A was significantly greater at 6 and 12 months than that immediately after stent placement; the mean lumen area was also significantly greater in group A than in group B at the same time points. The magnesium alloy covered stents proved to be an effective approach for occlusion of lateral aneurysm in the rabbit CCA; it provides distinct advantages that are comparable to that obtained with the Willis covered stent.

Creation of sidewall aneurysm in rabbits: aneurysm patency and growth follow-up.

PubMed

Ding, Yong Hong; Tieu, Tai; Kallmes, David F

2014-01-01

To explore the patency and growth of surgical sidewall aneurysms in rabbits. Forty sidewall aneurysms were created in the right common carotid artery (RCCA). Intravenous digital subtraction angiography (DSA) through the ear vein was performed immediately after creation. Three weeks later, intra-arterial DSA through the femoral artery was performed. Aneurysm sizes (neck, width, height and volume) were measured and calculated immediately after creation and 3 weeks later. Aneurysm patency after creation was evaluated. Differences in aneurysm sizes immediately after creation and 3 weeks later were compared using the Student's t test. Aneurysms and the parent artery remained patent in 38 (95%) of the 40 rabbits 3 weeks after creation. Two other rabbits (5%) showed aneurysm occlusion. There was a significant difference in aneurysm neck size 3 weeks after creation (3.6±0.9 mm vs 2.4±0.4 mm, p<0.0001). The aneurysm became wider 3 weeks later (5.8±1.5 mm vs 4.3±1.2 mm, p<0.0001). Aneurysm length was also larger than immediately after creation (6.1±1.3 mm vs 4.3±1.4 mm, p<0.0001). The aneurysm volume was larger than that created immediately (127.5±89.4 mm(3) vs 51.0±34.9 mm(3), p<0.0001). The patency rate of sidewall aneurysms in rabbits is high. The aneurysm keeps growing for at least 3 weeks after creation.

Multilevel segmentation of intracranial aneurysms in CT angiography images

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yan; Zhang, Yue, E-mail: y.zhang525@gmail.com; Navarro, Laurent

Purpose: Segmentation of aneurysms plays an important role in interventional planning. Yet, the segmentation of both the lumen and the thrombus of an intracranial aneurysm in computed tomography angiography (CTA) remains a challenge. This paper proposes a multilevel segmentation methodology for efficiently segmenting intracranial aneurysms in CTA images. Methods: The proposed methodology first uses the lattice Boltzmann method (LBM) to extract the lumen part directly from the original image. Then, the LBM is applied again on an intermediate image whose lumen part is filled by the mean gray-level value outside the lumen, to yield an image region containing part ofmore » the aneurysm boundary. After that, an expanding disk is introduced to estimate the complete contour of the aneurysm. Finally, the contour detected is used as the initial contour of the level set with ellipse to refine the aneurysm. Results: The results obtained on 11 patients from different hospitals showed that the proposed segmentation was comparable with manual segmentation, and that quantitatively, the average segmentation matching factor (SMF) reached 86.99%, demonstrating good segmentation accuracy. Chan–Vese method, Sen’s model, and Luca’s model were used to compare the proposed method and their average SMF values were 39.98%, 40.76%, and 77.11%, respectively. Conclusions: The authors have presented a multilevel segmentation method based on the LBM and level set with ellipse for accurate segmentation of intracranial aneurysms. Compared to three existing methods, for all eleven patients, the proposed method can successfully segment the lumen with the highest SMF values for nine patients and second highest SMF values for the two. It also segments the entire aneurysm with the highest SMF values for ten patients and second highest SMF value for the one. This makes it potential for clinical assessment of the volume and aspect ratio of the intracranial aneurysms.« less

Aortic Wall Inflammation Predicts Abdominal Aortic Aneurysm Expansion, Rupture, and Need for Surgical Repair.

PubMed

2017-08-29

Ultrasmall superparamagnetic particles of iron oxide (USPIO) detect cellular inflammation on magnetic resonance imaging (MRI). In patients with abdominal aortic aneurysm, we assessed whether USPIO-enhanced MRI can predict aneurysm growth rates and clinical outcomes. In a prospective multicenter open-label cohort study, 342 patients with abdominal aortic aneurysm (diameter ≥40 mm) were classified by the presence of USPIO enhancement and were monitored with serial ultrasound and clinical follow-up for ≥2 years. The primary end point was the composite of aneurysm rupture or repair. Participants (85% male, 73.1±7.2 years) had a baseline aneurysm diameter of 49.6±7.7 mm, and USPIO enhancement was identified in 146 (42.7%) participants, absent in 191 (55.8%), and indeterminant in 5 (1.5%). During follow-up (1005±280 days), 17 (5.0%) abdominal aortic aneurysm ruptures, 126 (36.8%) abdominal aortic aneurysm repairs, and 48 (14.0%) deaths occurred. Compared with those without uptake, patients with USPIO enhancement have increased rates of aneurysm expansion (3.1±2.5 versus 2.5±2.4 mm/year, P =0.0424), although this was not independent of current smoking habit ( P =0.1993). Patients with USPIO enhancement had higher rates of aneurysm rupture or repair (47.3% versus 35.6%; 95% confidence intervals, 1.1-22.2; P =0.0308). This finding was similar for each component of rupture (6.8% versus 3.7%, P =0.1857) or repair (41.8% versus 32.5%, P =0.0782). USPIO enhancement was associated with reduced event-free survival for aneurysm rupture or repair ( P =0.0275), all-cause mortality ( P =0.0635), and aneurysm-related mortality ( P =0.0590). Baseline abdominal aortic aneurysm diameter ( P <0.0001) and current smoking habit ( P =0.0446) also predicted the primary outcome, and the addition of USPIO enhancement to the multivariate model did not improve event prediction (c-statistic, 0.7935-0.7936). USPIO-enhanced MRI is a novel approach to the identification of aortic wall cellular inflammation in patients with abdominal aortic aneurysms and predicts the rate of aneurysm growth and clinical outcome. However, it does not provide independent prediction of aneurysm expansion or clinical outcomes in a model incorporating known clinical risk factors. URL: http://www.isrctn.com. Unique identifier: ISRCTN76413758. © 2017 The Authors.

Intrasylvian/Intracerebral Hematomas Associated with Ruptured Middle Cerebral Artery Aneurysms: A Single-Center Series and Literature Review.

PubMed

Zhang, Yupeng; Hu, Quan; Xue, Hao; Zhang, Mingran; Shen, Jie; Deng, Lin; Liu, Qinglin; Li, Gang

2017-02-01

Ruptured middle cerebral artery (MCA) aneurysms usually lead to subarachnoid hemorrhage (SAH), and several cases have shown concomitant intrasylvian or intracerebral hematomas. The objective of this study was to compare the clinical and radiographic characteristics with their different outcomes. The charts of 30 consecutive patients with ruptured MCA aneurysm-related intracranial hematoma were retrospectively reviewed. These patients were dichotomized into an intrasylvian hematoma (ISH) group and an intracerebral hematoma (ICH) group by the presence of intrahematomal contrast-enhancing vessel; for patients under open surgery, hematoma type was further confirmed by intraoperative observation. The characteristics were compared between these 2 groups (ie, age, gender, history of hypertension, history of smoking, systolic pressure at admission, hematoma volume, size and side of aneurysms, the angle between the pointing direction of the aneurysm and the MCA trunk [denoted as α], middle line shifting, treatment modality, and outcome). All the angles are measured in the anterior-posterior projection. In our series, only hematoma volume, the angle α, and the middle line shift showed statistical significance regarding prognosis between 2 hematoma groups. An angle α between 109.0°and 216.0° is associated with ISH, whereas aneurysm with an angle beyond this range indicates ICH. In our series, patients in the ICH group had a larger hematoma volume compared with the ISH patients (33.3 ± 17.6 vs. 11.5 ± 10.5; P = 0.002). There exists no statistical difference regarding prognosis between these 2 groups, even although there is a trend toward worse recovery for patients in the ISH group (Glasgow Outcome Scale score, 3.0 ± 1.3 vs. 3.8 ± 1.9; P = 0.07). In our series, the prognosis of patients with ICH was worse than that of patients with ISH. Early discrimination of these 2 types of hematoma helps to predict future outcome; an angle (between the pointing direction of aneurysm and the MCA trunk) between 109.0°and 216.0° is associated with ISH, whereas aneurysm with an angle beyond this range suggests ICH. Copyright © 2016 Elsevier Inc. All rights reserved.

Successful Coil Embolization of a Ruptured Basilar Artery Aneurysm in a Child with Leukemia: A Case Report

PubMed Central

HAYASHI, Shihori; MAEHARA, Taketoshi; MUKAWA, Maki; AOYAGI, Masaru; YOSHINO, Yoshikazu; NEMOTO, Shigeru; ONO, Toshiaki; OHNO, Kikuo

2014-01-01

Ruptured intracranial aneurysms are rare in the pediatric population compared to adults. This has incited considerable discussion on how to treat children with this condition. Here, we report a child with a ruptured saccular basilar artery aneurysm that was successfully treated with coil embolization. A 12-year-old boy with acute lymphoblastic leukemia and accompanying abdominal candidiasis after chemotherapy suddenly complained of a severe headache and suffered consciousness disturbance moments later. Computed tomography scans and cerebral angiography demonstrated acute hydrocephalus and subarachnoid hemorrhage caused by saccular basilar artery aneurysm rupture. External ventricular drainage was performed immediately. Because the patient was in severe condition and did not show remarkable signs of central nervous system infection in cerebrospinal fluid studies, we applied endovascular treatment for the ruptured saccular basilar artery aneurysm, which was successfully occluded with coils. The patient recovered without new neurological deficits after ventriculoperitoneal shunting. Recent reports indicate that both endovascular and microsurgical techniques can be used to effectively treat ruptured cerebral aneurysms in pediatric patients. A minimally invasive endovascular treatment was effective in the present case, but long-term follow-up will be necessary to confirm the efficiency of endovascular treatment for children with ruptured saccular basilar artery aneurysms. PMID:24257487

Successful coil embolization of a ruptured basilar artery aneurysm in a child with leukemia: a case report.

PubMed

Hayashi, Shihori; Maehara, Taketoshi; Mukawa, Maki; Aoyagi, Masaru; Yoshino, Yoshikazu; Nemoto, Shigeru; Ono, Toshiaki; Ohno, Kikuo

2014-01-01

Ruptured intracranial aneurysms are rare in the pediatric population compared to adults. This has incited considerable discussion on how to treat children with this condition. Here, we report a child with a ruptured saccular basilar artery aneurysm that was successfully treated with coil embolization. A 12-year-old boy with acute lymphoblastic leukemia and accompanying abdominal candidiasis after chemotherapy suddenly complained of a severe headache and suffered consciousness disturbance moments later. Computed tomography scans and cerebral angiography demonstrated acute hydrocephalus and subarachnoid hemorrhage caused by saccular basilar artery aneurysm rupture. External ventricular drainage was performed immediately. Because the patient was in severe condition and did not show remarkable signs of central nervous system infection in cerebrospinal fluid studies, we applied endovascular treatment for the ruptured saccular basilar artery aneurysm, which was successfully occluded with coils. The patient recovered without new neurological deficits after ventriculoperitoneal shunting. Recent reports indicate that both endovascular and microsurgical techniques can be used to effectively treat ruptured cerebral aneurysms in pediatric patients. A minimally invasive endovascular treatment was effective in the present case, but long-term follow-up will be necessary to confirm the efficiency of endovascular treatment for children with ruptured saccular basilar artery aneurysms.

Measurement with microscopic MRI and simulation of flow in different aneurysm models.

PubMed

Edelhoff, Daniel; Walczak, Lars; Frank, Frauke; Heil, Marvin; Schmitz, Inge; Weichert, Frank; Suter, Dieter

2015-10-01

The impact and the development of aneurysms depend to a significant degree on the exchange of liquid between the regular vessel and the pathological extension. A better understanding of this process will lead to improved prediction capabilities. The aim of the current study was to investigate fluid-exchange in aneurysm models of different complexities by combining microscopic magnetic resonance measurements with numerical simulations. In order to evaluate the accuracy and applicability of these methods, the fluid-exchange process between the unaltered vessel lumen and the aneurysm phantoms was analyzed quantitatively using high spatial resolution. Magnetic resonance flow imaging was used to visualize fluid-exchange in two different models produced with a 3D printer. One model of an aneurysm was based on histological findings. The flow distribution in the different models was measured on a microscopic scale using time of flight magnetic resonance imaging. The whole experiment was simulated using fast graphics processing unit-based numerical simulations. The obtained simulation results were compared qualitatively and quantitatively with the magnetic resonance imaging measurements, taking into account flow and spin-lattice relaxation. The results of both presented methods compared well for the used aneurysm models and the chosen flow distributions. The results from the fluid-exchange analysis showed comparable characteristics concerning measurement and simulation. Similar symmetry behavior was observed. Based on these results, the amount of fluid-exchange was calculated. Depending on the geometry of the models, 7% to 45% of the liquid was exchanged per second. The result of the numerical simulations coincides well with the experimentally determined velocity field. The rate of fluid-exchange between vessel and aneurysm was well-predicted. Hence, the results obtained by simulation could be validated by the experiment. The observed deviations can be caused by the noise in the measurement and by the limited resolution of the simulation. The resulting differences are small enough to allow reliable predictions of the flow distribution in vessels with stents and for pulsed blood flow.

Hyperglycemia Suppresses Calcium Phosphate-Induced Aneurysm Formation Through Inhibition of Macrophage Activation.

PubMed

Tanaka, Teruyoshi; Takei, Yuichiro; Yamanouchi, Dai

2016-03-28

The aim of this study was to elucidate aspects of diabetes mellitus-induced suppression of aneurysm. We hypothesized that high glucose suppresses aneurysm by inhibiting macrophage activation via activation of Nr1h2 (also known as liver X receptor β), recently characterized as a glucose-sensing nuclear receptor. Calcium phosphate (CaPO4)-induced aneurysm formation was significantly suppressed in the arterial wall in type 1 and 2 diabetic mice. A murine macrophage cell line, RAW264.7, was treated with tumor necrosis factor α (TNF-α) plus CaPO4 and showed a significant increase in matrix metalloproteinase 9 (Mmp9) mRNA and secreted protein expression compared with TNF-α alone. Elevated Mmp9 expression was significantly suppressed by hyperglycemic conditions (15.5 mmol/L glucose) compared with normoglycemic conditions (5.5 mmol/L glucose) or normoglycemic conditions with high osmotic pressure (5.5 mmol/L glucose +10.0 mmol/L mannitol). Nr1h2 mRNA and protein expression were suppressed by treatment with TNF-α plus CaPO4 but were restored by hyperglycemic conditions. Activation of Nr1h2 by the antagonist GW3965 during stimulation with TNF-α plus CaPO4 mimicked hyperglycemic conditions and inhibited Mmp9 upregulation, whereas the deactivation of Nr1h2 by small interfering RNA (siRNA) under hyperglycemic conditions canceled the suppressive effect and restored Mmp9 expression induced by TNF-α plus CaPO4. Moreover, Nr1h2 activation with GW3965 significantly suppressed CaPO4-induced aneurysm in mice compared with vehicle-injected control mice. Our results show that hyperglycemia suppresses macrophage activation and aneurysmal degeneration through the activation of Nr1h2. Although further validation of the underlying pathway is necessary, targeting Nr1h2 is a potential therapeutic approach to treating aneurysm. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Application of actuator-driven pulsed water jet in aneurysmal subarachnoid hemorrhage surgery: its effectiveness for dissection around ruptured aneurysmal walls and subarachnoid clot removal.

PubMed

Endo, Hidenori; Endo, Toshiki; Nakagawa, Atsuhiro; Fujimura, Miki; Tominaga, Teiji

2017-07-01

In clipping surgery for aneurysmal subarachnoid hemorrhage (aSAH), critical steps include clot removal and dissection of aneurysms without premature rupture or brain injuries. To pursue this goal, a piezo actuator-driven pulsed water jet (ADPJ) system was introduced in this study. This study included 42 patients, who suffered aSAH and underwent clipping surgery. Eleven patients underwent surgery with the assistance of the ADPJ system (ADPJ group). In the other 31 patients, surgery was performed without the ADPJ system (Control group). The ADPJ system was used for clot removal and aneurysmal dissection. The clinical impact of the ADPJ system was judged by comparing the rate of premature rupture, degree of clot removal, and clinical outcomes. Intraoperatively, a premature rupture was encountered in 18.2 and 25.8% of cases in the ADPJ and control groups, respectively. Although the differences were not statistically significant, intraoperative observation suggested that the ADPJ system was effective in clot removal and dissection of aneurysms in a safe manner. Computed tomography scans indicated the achievement of higher degrees of clot removal, especially when the ADPJ system was used for cases with preoperative clot volumes of more than 25 ml (p = 0.047, Mann-Whitney U test). Clinical outcomes, including incidence of postoperative brain injury or symptomatic vasospasm, were similar in both groups. We described our preliminary surgical results using the ADPJ system for aSAH. Although further study is needed, the ADPJ system was considered a safe and effective tool for clot removal and dissection of aneurysms.

Identification of the inflow zone of unruptured cerebral aneurysms: comparison of 4D flow MRI and 3D TOF MRA data.

PubMed

Futami, K; Sano, H; Misaki, K; Nakada, M; Ueda, F; Hamada, J

2014-07-01

The hemodynamics of the inflow zone of cerebral aneurysms may be a key factor in coil compaction and recanalization after endovascular coil embolization. We performed 4D flow MR imaging in conjunction with 3D TOF MRA and compared their ability to identify the inflow zone of unruptured cerebral aneurysms. This series comprised 50 unruptured saccular cerebral aneurysms in 44 patients. Transluminal color-coded 3D MRA images were created by selecting the signal-intensity ranges on 3D TOF MRA images that corresponded with both the luminal margin and the putative inflow. 4D flow MR imaging demonstrated the inflow zone and yielded inflow velocity profiles for all 50 aneurysms. In 18 of 24 lateral-projection aneurysms (75%), the inflow zone was located distally on the aneurysmal neck. The maximum inflow velocity ranged from 285 to 922 mm/s. On 4D flow MR imaging and transluminal color-coded 3D MRA studies, the inflow zone of 32 aneurysms (64%) was at a similar location. In 91% of aneurysms whose neck section plane angle was <30° with respect to the imaging section direction on 3D TOF MRA, depiction of the inflow zone was similar on transluminal color-coded 3D MRA and 4D flow MR images. 4D flow MR imaging can demonstrate the inflow zone and provide inflow velocity profiles. In aneurysms whose angle of the neck-section plane is obtuse vis-a-vis the imaging section on 3D TOF MRA scans, transluminal color-coded 3D MRA may depict the inflow zone reliably. © 2014 by American Journal of Neuroradiology.

Particularly interesting Cys-His-rich protein is highly expressed in human intracranial aneurysms and resists aneurysmal rupture

PubMed Central

Peng, Yu-Tao; Shi, Xiang-En; Li, Zhi-Qiang; He, Xin; Sun, Yu-Ming

2016-01-01

Particularly interesting Cys-His-rich protein (PINCH) has several biological functions in cancer development, invasion and metastasis in malignant cells, and the expression of PINCH is upregulated in several cancer types, including breast cancer, gastric adenocarcinoma and rectal cancer. However, the contribution of PINCH to human cerebral aneurysms remains largely unknown. Therefore, the significance of PINCH expression in cerebral aneurysm growth and rupture was examined in the present study. The protein expression levels of alpha-smooth muscle actin, osteopontin (OPN), matrix metalloproteinase (MMP) 9 and PINCH were evaluated using immunohistochemistry and western blot analyses. The results demonstrate that the protein expression levels of OPN, MMP9 and PINCH in the unruptured intracranial aneurysm (UA) and ruptured intracranial aneurysm (RA) groups were markedly higher than those of the control group, whereas OPN and PINCH expression levels were decreased in the RA group compared to those of the UA group. In addition, there was a strong correlation between PINCH and tumor size (r=0.650 and P=0.0026), as well as between PINCH and OPN (r=0.639 and P=0.0033) in the unruptured cerebral aneurysms. However, the correlation between PINCH and tumor size (r=0.450 and P=0.1393) and between PINCH and OPN (r=0.366 and P=0.2426) revealed no obvious difference in the ruptured cerebral aneurysms. In conclusion, PINCH was highly expressed in the UAs, which may be a critical factor for preventing aneurysmal rupture. Moreover, PINCH may facilitate intracranial aneurysm progression, at least partially, through the activation of extracellular signal-regulated kinase signaling and the suppression of c-Jun N-terminal kinase signaling. PMID:28101173

Particularly interesting Cys-His-rich protein is highly expressed in human intracranial aneurysms and resists aneurysmal rupture.

PubMed

Peng, Yu-Tao; Shi, Xiang-En; Li, Zhi-Qiang; He, Xin; Sun, Yu-Ming

2016-12-01

Particularly interesting Cys-His-rich protein (PINCH) has several biological functions in cancer development, invasion and metastasis in malignant cells, and the expression of PINCH is upregulated in several cancer types, including breast cancer, gastric adenocarcinoma and rectal cancer. However, the contribution of PINCH to human cerebral aneurysms remains largely unknown. Therefore, the significance of PINCH expression in cerebral aneurysm growth and rupture was examined in the present study. The protein expression levels of alpha-smooth muscle actin, osteopontin (OPN), matrix metalloproteinase (MMP) 9 and PINCH were evaluated using immunohistochemistry and western blot analyses. The results demonstrate that the protein expression levels of OPN, MMP9 and PINCH in the unruptured intracranial aneurysm (UA) and ruptured intracranial aneurysm (RA) groups were markedly higher than those of the control group, whereas OPN and PINCH expression levels were decreased in the RA group compared to those of the UA group. In addition, there was a strong correlation between PINCH and tumor size ( r =0.650 and P=0.0026), as well as between PINCH and OPN ( r =0.639 and P=0.0033) in the unruptured cerebral aneurysms. However, the correlation between PINCH and tumor size ( r =0.450 and P=0.1393) and between PINCH and OPN ( r =0.366 and P=0.2426) revealed no obvious difference in the ruptured cerebral aneurysms. In conclusion, PINCH was highly expressed in the UAs, which may be a critical factor for preventing aneurysmal rupture. Moreover, PINCH may facilitate intracranial aneurysm progression, at least partially, through the activation of extracellular signal-regulated kinase signaling and the suppression of c-Jun N-terminal kinase signaling.

Effect of short-term ε-aminocaproic acid treatment on patients undergoing endovascular coil embolization following aneurysmal subarachnoid hemorrhage.

PubMed

Malekpour, Mahdi; Kulwin, Charles; Bohnstedt, Bradley N; Radmand, Golnar; Sethia, Rishabh; Mendenhall, Stephen K; Weyhenmeyer, Jonathan; Hendricks, Benjamin K; Leipzig, Thomas; Payner, Troy D; Shah, Mitesh V; Scott, John; DeNardo, Andrew; Sahlein, Daniel; Cohen-Gadol, Aaron A

2017-05-01

OBJECTIVE Aneurysmal rebleeding before definitive obliteration of the aneurysm is a cause of mortality and morbidity. There are limited data on the role of short-term antifibrinolytic therapy among patients undergoing endovascular intervention. METHODS All consecutive patients receiving endovascular therapy for their ruptured saccular aneurysm at the authors' institution between 2000 and 2011 were included in this study. These patients underwent endovascular coiling of their aneurysm within 72 hours of admission. In patients receiving ε-aminocaproic acid (EACA), the EACA administration was continued until the time of the endovascular procedure. Complications and clinical outcomes of endovascular treatment after aneurysmal subarachnoid hemorrhage (aSAH) were compared between EACA-treated and untreated patients. RESULTS During the 12-year study period, 341 patients underwent endovascular coiling. Short-term EACA treatment was administered in 146 patients and was withheld in the other 195 patients. EACA treatment did not change the risk of preinterventional rebleeding in this study (OR 0.782, 95% CI 0.176-3.480; p = 0.747). Moreover, EACA treatment did not increase the rate of thromboembolic events. On the other hand, patients who received EACA treatment had a significantly longer duration of hospital stay compared with their counterparts who were not treated with EACA (median 19 days, interquartile range [IQR] 12.5-30 days vs median 14 days, IQR 10-23 days; p < 0.001). EACA treatment was associated with increased odds of shunt requirement (OR 2.047, 95% CI 1.043-4.018; p = 0.037) and decreased odds of developing cardiac complications (OR 0.138, 95% CI 0.031-0.604; p = 0.009) and respiratory insufficiency (OR 0.471, 95% CI 0.239-0.926; p = 0.029). Short-term EACA treatment did not affect the Glasgow Outcome Scale score at discharge, 6 months, or 1 year following discharge. CONCLUSIONS In this study, short-term EACA treatment in patients who suffered from aSAH and received endovascular aneurysm repair did not decrease the risk of preinterventional rebleeding or increase the risk of thrombotic events. EACA did not affect outcome. Randomized clinical trials are required to provide robust clinical recommendation on short-term use of EACA.

Inter-observer variability in diagnosing radiological features of aneurysmal subarachnoid hemorrhage; a preliminary single centre study comparing observers from different specialties and levels of training.

PubMed

Siddiqui, Usman T; Khan, Anjum F; Shamim, Muhammad Shahzad; Hamid, Rana Shoaib; Alam, Muhammad Mehboob; Emaduddin, Muhammad

2014-01-01

A noncontrast computed tomography (CT) scan remains the initial radiological investigation of choice for a patient with suspected aneurysmal subarachnoid hemorrhage (aSAH). This initial scan may be used to derive key information about the underlying aneurysm which may aid in further management. The interpretation, however, is subject to the skill and experience of the interpreting individual. The authors here evaluate the interpretation of such CT scans by different individuals at different levels of training, and in two different specialties (Radiology and Neurosurgery). Initial nonontrast CT scan of 35 patients with aSAH was evaluated independently by four different observers. The observers selected for the study included two from Radiology and two from Neurosurgery at different levels of training; a resident currently in mid training and a resident who had recently graduated from training of each specialty. Measured variables included interpreter's suspicion of presence of subarachnoid blood, side of the subarachnoid hemorrhage, location of the aneurysm, the aneurysm's proximity to vessel bifurcation, number of aneurysm(s), contour of aneurysm(s), presence of intraventricular hemorrhage (IVH), intracerebral hemorrhage (ICH), infarction, hydrocephalus and midline shift. To determine the inter-observer variability (IOV), weighted kappa values were calculated. There was moderate agreement on most of the CT scan findings among all observers. Substantial agreement was found amongst all observers for hydrocephalus, IVH, and ICH. Lowest agreement rates were seen in the location of aneurysm being supra or infra tentorial. There were, however, some noteworthy exceptions. There was substantial to almost perfect agreement between the radiology graduate and radiology resident on most CT findings. The lowest agreement was found between the neurosurgery graduate and the radiology graduate. Our study suggests that although agreements were seen in the interpretation of some of the radiological features of aSAH, there is still considerable IOV in the interpretation of most features among physicians belonging to different levels of training and different specialties. Whether these might affect management or outcome is unclear.

Comparison of remnant size in embolized intracranial aneurysms measured at follow-up with DSA and MRA.

PubMed

Serafin, Zbigniew; Strześniewski, Piotr; Lasek, Władysław; Beuth, Wojciech

2012-12-01

The possibility of recanalization and the need for retreatment are the most important limitations of intracranial aneurysm embolization. The purpose of the study was to compare the size of aneurysm remnants measured at follow-up with three-dimensional digital subtracted angiography (3D-DSA) and magnetic resonance angiography (MRA). Twenty-six aneurysms were found incompletely occluded in 72 consecutively examined patients at a follow-up after 3 months. The diameters and volume of aneurysm remnants were compared between 3D-DSA, time-of-flight MRA (TOF-MRA), contrast-enhanced TOF-MRA (CE-TOF-MRA), and contrast-enhanced MRA (CE-MRA) at 1.5 T. There was a significant correlation between remnant volumes calculated based on 3D-DSA and all MRA modalities. The intraobserver variability of the measurements ranged from 3.4 to 4.1 % and the interobserver variability from 5.8 to 7.3 %. There were no significant differences in the variability between the techniques. The mean residual filling volume ranged from 16.3 ± 19.0 mm(3) in TOF-MRA to 30.5 ± 44.6 mm(3) in 3D-DSA (P < 0.04). Significant differences were found in the volumes measured with 3D-DSA and CE-MRA as compared to TOF-MRA and CE-TOF-MRA (P < 0.01). There was a moderate significant correlation between the residual filling and the relative error of measurement in the case of TOF-MRA and CE-TOF-MRA. TOF-MRA seems to underestimate the size of aneurysm remnants detected at follow-up and should not be used as a sole imaging method to decide on re-embolization.

Comparative study of novel endovascular treatment techniques for intracranial aneurysms

NASA Astrophysics Data System (ADS)

Cantón, Gádor; Lasheras, Juan C.; Levy, David I.; Sparks, Steven R.

2002-11-01

Intracranial aneurysms are life-threatening vascular lesions, which are potentially treatable to avoid the consequences of their rupture. Current treatments, either surgical or endovascular, are all guided to reduce the hemodynamic forces acting on the aneurysm wall in an effort to minimize the risk of rupture. Surgical clipping is still the most used technique to treat this type of aneurysm but there is a continued demand for less invasive approaches. This has led to the development of several endovascular techniques. We report here a comparative study of the reduction in the hemodynamic stresses and the modification of the flow in the parent vessel resulting from the use of three different techniques. The first one consists of endosaccular packing with platinum coils (GDC, Target Therapeutics), which is already widely used but its long-term efficacy has not yet been determined. The second one consists of the embolization of the aneurismal sac with Onyx, a polymer which hardens when in contact with the blood (being developed by Micro Therapeutics, Inc.). The third one involves the packing of the sac with hydrocoils, platinum wires coated with a gel which quickly hydrates when in contact with blood (developed by MicroVention). A Digital Particle Image Velocimetry (DPIV) system is used to measure in vitro the velocity field inside a model of an ACOM aneurysm (an aneurysm forming in the anterior communicating artery). Physiological accurate pulsatile flow conditions are input to the arterial model through a programmable pump. The measurements show that although all treatment techniques lead to a reduction in both normal and tangential shear stresses on the aneurismal sac, each one of them also leads to different modifications of the flow in the parent vessel which may have consequences related to potential for clotting. Comparison of the untreated aneurysm with the above three treated cases also showed that the characteristics of the wall shear stresses on the parent vessel are modified by the packing method.

Treatment of cerebral aneurysms in children: analysis of the Kids' Inpatient Database.

PubMed

Alawi, Aws; Edgell, Randall C; Elbabaa, Samer K; Callison, R Charles; Khalili, Yasir Al; Allam, Hesham; Alshekhlee, Amer

2014-07-01

OBJECT.: Endovascular coiling and surgical clipping are viable treatment options of cerebral aneurysms. Outcome data of these treatments in children are limited. The objective of this study was to determine hospital mortality and complication rates associated with surgical clipping and coil embolization of cerebral aneurysms in children, and to evaluate the trend of hospitals' use of these treatments. The authors identified a cohort of children admitted with the diagnoses of cerebral aneurysms and aneurysmal subarachnoid hemorrhage from the Kids' Inpatient Database for the years 1998 through 2009. Hospital-associated complications and in-hospital mortality were compared between the treatment groups and stratified by aneurysmal rupture status. A multivariate regression analysis was used to identify independent variables associated with in-hospital mortality. The Cochrane-Armitage test was used to assess the trend of hospital use of these operations. A total of 1120 children were included in this analysis; 200 (18%) underwent aneurysmal clipping and 920 (82%) underwent endovascular coiling. Overall in-hospital mortality was higher in the surgical clipping group compared with the coil embolization group (6.09% vs 1.65%, respectively; adjusted odds ratio [OR] 2.52, 95% CI 0.97-6.53, p = 0.05). The risk of postoperative stroke or hemorrhage was similar between the two treatment groups (p = 0.86). Pulmonary complications and systemic infection were higher in the surgical clipping population (p < 0.05). The rate of US hospitals' use of endovascular coiling has significantly increased over the years included in this study (p < 0.0001). Teaching hospitals were associated with a lower risk of death (OR 0.13, 95% CI 0.03-0.46; p = 0.001). Although both treatments are valid, endovascular coiling was associated with fewer deaths and shorter hospital stays than clip placement. The trend of hospitals' use of coiling operations has increased in recent years.

Four-year trends in the treatment of cerebral aneurysms in Poland in 2009-2012.

PubMed

Tykocki, Tomasz; Kostyra, Kacper; Czyż, Marcin; Kostkiewicz, Bogusław

2014-05-01

The dilemma concerning the appropriate treatment of the intracranial aneurysms (IAs) has not yet been resolved and still remains under fierce debate. This study refers to the recent trends in the use of and outcomes related to coiling compared with clipping for unruptured and ruptured IAs in Poland over a 4-year period. The analysis refers to treatment of IAs performed in Poland between 2009-2012. Patients' records were cross-matched by ICD-9 codes for ruptured SAH (430) or unruptured cerebral aneurysm (437.3) along with codes for clipping (39.51) and coiling (39.79, 39.72, or 39.52). Multivariable logistic regression was used to compare in-hospital deaths, hospital length of stay (LOS), therapy allocation and aneurysm locations in unruptured vs. ruptured and clipped vs. coiled groups. Differences in the number of procedures between 16 administrative regions were standardized per 100,000 people. In 2009-2012, 11,051 procedures were identified, including 5,968 ruptured and 5,083 unruptured aneurysms. Overall increase was 2.3 % in clipping and 13.1 % in coiling; a significant trend was found in endovascular procedures (p = 0.044). Ruptured aneurysms were clipped more frequently (OR = 1.66;); in unruptured IAs, endovascular procedure was preferred 3.5 times more than clipping. The annual in-hospital mortality was 7.6 % in clipping and 6.7 % in endovascular treatment. LOS was two times longer after clipping in unruptured aneurysms (OR = 2.013). After the procedures were standardized per 100,000 people, the average for Poland was established as 9.09 in 2009, 10.86 in 2010, 10.55 in 2011, and 11.49 in 2012. This index had the highest values in Mazovia (12.9, 2009; 15.4, 2010; 17.4, 2011; 18.6, 2012. Data analysis revealed an increase in overall number of IAs treated in Poland between 2009-2012. A significant upward trend of endovascular procedures was found, whereas the number of clipped aneurysms remained relatively steady over the study period.

Surgical treatment of pararenal aortic aneurysms in the elderly.

PubMed

Illuminati, G; D'Urso, A; Ceccanei, G; Caliò, F; Vietri, F

2007-12-01

Until fenestrated endografts will become the standard treatment of pararenal aortic aneurysms, open surgical repair will currently be employed for the repair of this condition. Suprarenal aortic control and larger surgical dissection represent additional technical requirements for the treatment of pararenal aneurysms compared to those of open infrarenal aortic aneurysms, which may be followed by an increased operative mortality and morbidity rate. As this may be especially true when dealing with pararenal aneurysms in an elderly patients' population, we decided to retrospectively review our results of open pararenal aortic aneurysm repair in elderly patients, in order to compare them with those reported in the literature. Twenty-one patients over 75 years of age were operated on for pararenal aortic aneurysms in a ten-year period. Exposure of the aorta was obtained by means of a retroperitoneal access, through a left flank incision on the eleventh rib. When dealing with interrenal aortic aneurysm the left renal artery was revascularized with a retrograde bypass arising from the aortic graft, proximally bevelled on the ostium of the right renal artery. Two patients died of acute intestinal ischemia, yielding a postoperative mortality of 9.5%. Nonfatal complications included 2 pleural effusions, a transitory rise in postoperative serum creatinine levels in 3 cases, and one retroperitoneal hematoma. Mean renal ischemia time was 23 min, whereas mean visceral ischemia time was 19 min. Mean inhospital stay was 11 days. Pararenal aortic aneurysms in the elderly can be surgically repaired with results that are similar to those obtained in younger patients.

Hemodynamic vascular biomarkers for initiation of paraclinoid internal carotid artery aneurysms using patient-specific computational fluid dynamic simulation based on magnetic resonance imaging.

PubMed

Watanabe, Tomoya; Isoda, Haruo; Takehara, Yasuo; Terada, Masaki; Naito, Takehiro; Kosugi, Takafumi; Onishi, Yuki; Tanoi, Chiharu; Izumi, Takashi

2018-05-01

We performed computational fluid dynamics (CFD) for patients with and without paraclinoid internal carotid artery (ICA) aneurysms to evaluate the distribution of vascular biomarkers at the aneurysm initiation sites of the paraclinoid ICA. This study included 35 patients who were followed up for aneurysms using 3D time of flight (TOF) magnetic resonance angiography (MRA) and 3D cine phase-contrast MR imaging. Fifteen affected ICAs were included in group A with the 15 unaffected contralateral ICAs in group B. Thirty-three out of 40 paraclinoid ICAs free of aneurysms and arteriosclerotic lesions were included in group C. We deleted the aneurysms in group A based on the 3D TOF MRA dataset. We performed CFD based on MR data set and obtained wall shear stress (WSS), its derivatives, and streamlines. We qualitatively evaluated their distributions at and near the intracranial aneurysm initiation site among three groups. We also calculated and compared the normalized highest (nh-) WSS and nh-spatial WSS gradient (SWSSG) around the paraclinoid ICA among three groups. High WSS and SWSSG distribution were observed at and near the aneurysm initiation site in group A. High WSS and SWSSG were also observed at similar locations in group B and group C. However, nh-WSS and nh-SWSSG were significantly higher in group A than in group C, and nh-SWSSG was significantly higher in group A than in group B. Our findings indicated that nh-WSS and nh-SWSSG were good biomarkers for aneurysm initiation in the paraclinoid ICA.

From Bench to Bedside: Utility of the Rabbit Elastase Aneurysm Model in Pre-Clinical Studies of Intracranial Aneurysm Treatment

PubMed Central

Brinjikji, Waleed; Ding, Yong H; Kallmes, David F; Kadirvel, Ramanathan

2016-01-01

Summary Pre-clinical studies are important in helping practitioners and device developers improve techniques and tools for endovascular treatment of intracranial aneurysms. Thus, an understanding of the major animal models used in such studies is important. The New Zealand rabbit elastase induced arterial aneurysm of the common carotid artery is one of the most commonly used models in testing the safety and efficacy of new endovascular devices. In this review we discuss 1) various techniques used to create the aneurysm, 2) complications of aneurysm creation, 3) natural history of the arterial aneurysm, 4) histopathologic and hemodynamic features of the aneurysm 5) devices tested using this model and 6) weaknesses of the model. We demonstrate how pre-clinical studies using this model are applied in treatment of intracranial aneurysms in humans. The model has a similar hemodynamic, morphological and histologic characteristics to human aneurysms and demonstrates similar healing responses to coiling as human aneurysms. Despite these strengths however, the model does have many weaknesses including the fact that the model does not emulate the complex inflammatory processes affecting growing and ruptured aneurysms. Furthermore the model’s extracranial location affects its ability to be used in preclinical safety assessments of new devices. We conclude that the rabbit elastase model has characteristics that make it a simple and effective model for preclinical studies on the endovascular treatment of intracranial aneurysms however further work is needed to develop aneurysm models that simulate the histopathologic and morphologic characteristics of growing and ruptured aneurysms. PMID:25904642

A Modified Method for Creating Elastase-Induced Aneurysms by Ligation of Common Carotid Arteries in Rabbits and Its Effect on Surrounding Arteries.

PubMed

Kainth, Daraspreet; Salazar, Pascal; Safinia, Cyrus; Chow, Ricky; Bachour, Ornina; Andalib, Sasan; McKinney, Alexander M; Divani, Afshin A

2017-01-01

Rabbit models of intracranial aneurysms are frequently used in pre-clinical settings. This study aimed to demonstrate an alternative, extravascular method for creating elastase-induced aneurysms, and how ligation of the right common carotid arteries (RCCA) can impact flow redistribution into left CCA (LCCA). Elastase-induced aneurysms in 18 New Zealand rabbits (4.14 ± 0.314 kg) were created by applying 3-5 U of concentrated elastase solution to the exterior of the right and left CCA roots (RCCA and LCCA). After the induction of the aneurysm, the aneurysm was either kept intact to the rest of the corresponding CCA, severed from the rest of the CCA to allow for a free standing aneurysm, or was anchored to nearby tissue to influence the angle and orientation of the aneurysm with respect to the parent vessel. Ultrasound studies were performed before and after creation of aneurysms to collect blood flow measurements inside the aneurysm pouch and surrounding arteries. Prior to sacrificing the animals, computed tomography angiography studies were performed. Harvested aneurysmal tissues were used for histological analysis. Elastase-induced aneurysms were successfully created by the extravascular approach. Histological studies showed that the biological response was similar to human cerebral aneurysms and previously published elastase-induced rabbit aneurysm models. Ultrasound measurements indicated that after the RCCA was ligated, blood flow significantly increased in the LCCA at one-month follow-up. An alternate method for creating elastase-induced aneurysms has been demonstrated. The novel aspects of our method allow for ligation of one or both common carotid arteries to create a single or bilateral aneurysm with an ability to control the orientation of the induced aneurysm.

Follow-up of intracranial aneurysms treated with stent-assisted coiling: Comparison of contrast-enhanced MRA, time-of-flight MRA, and digital subtraction angiography.

PubMed

Marciano, David; Soize, Sébastien; Metaxas, Georgios; Portefaix, Christophe; Pierot, Laurent

2017-02-01

Data about non-invasive follow-up of aneurysm after stent-assisted coiling is scarce. We aimed to compare time-of-flight (TOF) magnetic resonance angiography (MRA) (3D-TOF-MRA) and contrast-enhanced MRA (CE-MRA) at 3-Tesla, with digital subtraction angiography (DSA) for evaluating aneurysm occlusion and parent artery patency after stent-assisted coiling. In this retrospective single-center study, patients were included if they had an intracranial aneurysm treated by stent-assisted coiling between March 2008 and June 2015, followed with both MRA sequences (3D-TOF-MRA and CE-MRA) at 3-Tesla and DSA, performed in an interval<48hours. Thirty-five aneurysms were included. Regarding aneurysm occlusion evaluation, agreement with DSA was better for CE-MRA (K=0.53) than 3D-TOF-MRA (K=0.28). Diagnostic accuracies for aneurysm remnant depiction were similar for 3D-TOF-MRA and CE-MRA (P=1). Both 3D-TOF-MRA (K=0.05) and CE-MRA (K=-0.04) were unable to detect pathological vessel compared to DSA, without difference in accuracy (P=0.68). For parent artery occlusion detection, agreement with DSA was substantial for 3D-TOF-MRA (K=0.64) and moderate for CE-MRA (K=0.45), with similar good diagnostic accuracies (P=1). After stent-assisted coiling treatment, 3D-TOF-MRA and CE-MRA demonstrated good accuracy to detect aneurysm remnant (but tended to overestimation). Although CE-MRA agreement with DSA was better, there was no statistical difference between 3D-TOF-MRA and CE-MRA accuracies. Both MRAs were unable to provide a precise evaluation of in-stent status but could detect parent vessel occlusion. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Anatomic suitability of aortoiliac aneurysms for next generation branched systems.

PubMed

Pearce, Benjamin J; Varu, Vinit N; Glocker, Roan; Novak, Zdenek; Jordan, William D; Lee, Jason T

2015-01-01

Preservation of internal iliac flow is an important consideration to prevent ischemic complications during endovascular aneurysm repair. We sought to determine the suitability of aortoiliac aneurysms for off-the-shelf iliac branched systems currently in clinical trial. Patients undergoing abdominal aortic aneurysm repair from 2004 to 2013 at 2 institutions were reviewed. Centerline diameters and lengths of aortoiliac morphology were measured using three-dimensional workstations and compared with inclusion/exclusion criteria for both Cook and Gore iliac branch devices. Of the nearly 2,400 aneurysm repairs performed during the study period, 99 patients had common iliac aneurysms suitable for imaging review. Eighteen of the 99 (18.2%) patients and 25/99 (25.3%) patients fit the inclusion criteria and would have been able to be treated using the Cook and Gore iliac branch devices, respectively. The most common reason for exclusion from Cook was internal iliac diameter of <6 or >9 mm (68/99, 68.7%). The most common reason for exclusion from Gore was proximal common iliac diameter of <17 mm (39/99, 39.4%) and inadequate internal iliac artery diameter of <6.5 or >13.5 mm (37/99, 37.3%). Comparing the included patients across both devices, a total of 35/99 (35.4%) of patients would be eligible for the treatment of aortoiliac aneurysms based on anatomic criteria. Only 35% of the aneurysm repairs involving common iliac arteries would have been candidates for the 2 iliac branch devices currently in trial based on anatomic criteria. The major common reason for exclusion is the internal iliac landing zone for both devices. Design modifications for future generation iliac branch technology should focus on diameter accommodations for the hypogastric branch stent and proximal and distal sizes of the iliac branch components. Familiarity with alternate branch preserving techniques is still needed in the majority of cases. Copyright © 2015 Elsevier Inc. All rights reserved.

CE-MRA for follow-up of aneurysms post stent-assisted coiling.

PubMed

Agid, R; Schaaf, M; Farb, Ri

2012-09-01

This study compared the accuracy of contrast-enhanced MR angiography (CE-MRA) to intra-arterial cerebral angiography (IA-DSA) for assessment of intracranial aneurysms after stent-assisted coiling and to check if the presence of a stent in the parent artery diminishes the accuracy of CE-MRA. Consecutive patients with cerebral aneurysms treated by stent-assisted coiling were evaluated retrospectively. Matching follow-up CE-MRA and IA-DSA were evaluated separately. Evaluation included the presence of aneurysmal remnant, patency and stenosis of parent artery. Twenty-seven patients with 28 aneurysms and 33 matched CE-MRA and IA-DSA studies were evaluated. Nineteen aneurysmal remnants were seen on CE-MRA and 16 on IA-DSA. CE-MRA diagnosed three aneurysmal remnants not appreciated on IA-DSA. Five other remnants were larger on CE-MRA than IA-DSA. None of the remnants were missed on CE-MRA. Parent arteries were patent on both modalities. CE-MRA showed false stenosis of the stented artery in six cases and exaggerated stenosis in two. In 18 cases, CE-MRA showed a short focal "pseudo-stenosis" where the stent's marker bands were located. This was noted whenever the stent's marker bands were located in an artery with luminal diameter ≤2 mm and was called "marker band effect". CE-MRA is an accurate technique for follow-up of aneurysms post stent-assisted coiling with excellent depiction of remnants in spite of the presence of a stent. Apparent stenosis of the stented parent artery on CE-MRA is often false or exaggerated. "Marker band effect" should be recognized as an artifact that appears when stent's marker bands are in a small artery.

CE-MRA for Follow-up of Aneurysms Post Stent-Assisted Coiling

PubMed Central

Agid, R.; Schaaf, M.; Farb, RI.

2012-01-01

Summary This study compared the accuracy of contrast-enhanced MR angiography (CE-MRA) to intra-arterial cerebral angiography (IA-DSA) for assessment of intracranial aneurysms after stent-assisted coiling and to check if the presence of a stent in the parent artery diminishes the accuracy of CE-MRA. Consecutive patients with cerebral aneurysms treated by stent-assisted coiling were evaluated retrospectively. Matching follow-up CE-MRA and IA-DSA were evaluated separately. Evaluation included the presence of aneurysmal remnant, patency and stenosis of parent artery. Twenty-seven patients with 28 aneurysms and 33 matched CE-MRA and IA-DSA studies were evaluated. Nineteen aneurysmal remnants were seen on CE-MRA and 16 on IA-DSA. CE-MRA diagnosed three aneurysmal remnants not appreciated on IA-DSA. Five other remnants were larger on CE-MRA than IA-DSA. None of the remnants were missed on CE-MRA. Parent arteries were patent on both modalities. CE-MRA showed false stenosis of the stented artery in six cases and exaggerated stenosis in two. In 18 cases, CE-MRA showed a short focal “pseudo-stenosis” where the stent’s marker bands were located. This was noted whenever the stent’s marker bands were located in an artery with luminal diameter ≤2 mm and was called “marker band effect”. CE-MRA is an accurate technique for follow-up of aneurysms post stent-assisted coiling with excellent depiction of remnants in spite of the presence of a stent. Apparent stenosis of the stented parent artery on CE-MRA is often false or exaggerated. “Marker band effect” should be recognized as an artifact that appears when stent’s marker bands are in a small artery. PMID:22958765

The predictive role of health-promoting behaviours and perceived stress in aneurysmal rupture.

PubMed

Lee, Mi-Sun; Park, Chang G; Hughes, Tonda L; Jun, Sang-Eun; Whang, Kum; Kim, Nahyun

2018-03-01

To examine the roles of two modifiable factors-health-promoting behaviours and perceived stress-in predicting aneurysmal rupture. Unruptured intracranial aneurysm detection produces significant stress and anxiety in patients because of the risk of rupture. Compared to nonmodifiable risk factors for rupture such as age, gender and aneurysm size/location, less attention has been given to modifiable risk factors. Two modifiable factors, health-promoting behaviours and perceived stress, have hardly been examined as potential predictors of rupture. This study used a cross-sectional design. We assessed 155 patients with intracranial aneurysms-that is, subarachnoid haemorrhage (n = 77) or unruptured intracranial aneurysm (n = 78)-to examine (i) baseline characteristics (patient and aneurysmal factors), (ii) health-related factors (lifestyle habits and health-promoting behaviour) and (iii) perceived stress levels (psychological stress and physical stress). Patient records provided medical histories and aneurysmal factors; other data were collected using a structured questionnaire addressing lifestyle habits, the Health-Promoting Lifestyle Profile-II to measure health-promoting behaviour and the Perceived Stress Questionnaire to measure perceived-psychological stress and perceived-physical stress levels. Bivariate analysis indicated that aneurysm rupture risk was associated with female gender, aneurysm size/location, defecation frequency, hyperlipidaemia, sedentary time, low Health-Promoting Lifestyle Profile-II mean scores and high perceived-psychological stress scores. After adjusting for known risk factors, the mean Health-Promoting Lifestyle Profile-II and perceived-psychological stress scores remained robust predictors of rupture. Furthermore, known risk factors combined with these scores had greater predictive power than known risk factors alone. Health-promoting behaviour and psychological stress are promising modifiable factors for reducing risk of aneurysmal rupture. Our findings may stimulate greater understanding of mechanisms underlying aneurysmal rupture and suggest practical strategies for nurses to employ in optimising conservative management of rupture risk by teaching patients how to modify their risk. Both health-promoting behaviour and perceived stress should be addressed when designing preventive nursing interventions for patients with unruptured intracranial aneurysm. © 2017 John Wiley & Sons Ltd.

Dissection and Aneurysm in Patients With Fibromuscular Dysplasia: Findings From the U.S. Registry for FMD.

PubMed

Kadian-Dodov, Daniella; Gornik, Heather L; Gu, Xiaokui; Froehlich, James; Bacharach, J Michael; Chi, Yung-Wei; Gray, Bruce H; Jaff, Michael R; Kim, Esther S H; Mace, Pamela; Sharma, Aditya; Kline-Rogers, Eva; White, Christopher; Olin, Jeffrey W

2016-07-12

Fibromuscular dysplasia (FMD) is a noninflammatory arterial disease that predominantly affects women. The arterial manifestations may include beading, stenosis, aneurysm, dissection, or tortuosity. This study compared the frequency, location, and outcomes of FMD patients with aneurysm and/or dissection to those of patients without. The U.S. Registry for FMD involves 12 clinical centers. This analysis included clinical history, diagnostic, and therapeutic procedure results for 921 FMD patients enrolled in the registry as of October 17, 2014. Aneurysm occurred in 200 patients (21.7%) and dissection in 237 patients (25.7%); in total, 384 patients (41.7%) had an aneurysm and/or a dissection by the time of FMD diagnosis. The extracranial carotid, renal, and intracranial arteries were the most common sites of aneurysm; dissection most often occurred in the extracranial carotid, vertebral, renal, and coronary arteries. FMD patients with dissection were younger at presentation (48.4 vs. 53.5 years of age, respectively; p < 0.0001) and experienced more neurological symptoms and other end-organ ischemic events than those without dissection. One-third of aneurysm patients (63 of 200) underwent therapeutic intervention for aneurysm repair. Patients with FMD have a high prevalence of aneurysm and/or dissection prior to or at the time of FMD diagnosis. Patients with dissection were more likely to experience ischemic events, and a significant number of patients with dissection or aneurysm underwent therapeutic procedures for these vascular events. Because of the high prevalence and associated morbidity in patients with FMD who have an aneurysm and/or dissection, it is recommended that every patient with FMD undergo one-time cross-sectional imaging from head to pelvis with computed tomographic angiography or magnetic resonance angiography. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Carotid and vertebral injury study (CAVIS) technique for characterization of blunt traumatic aneurysms with reliability assessment.

PubMed

Griessenauer, Christoph J; Foreman, Paul; Shoja, Mohammadali M; Kicielinski, Kimberly P; Deveikis, John P; Walters, Beverly C; Harrigan, Mark R

2015-04-01

Traumatic aneurysms occur in up to 20% of blunt traumatic extracranial carotid artery injuries. Currently there is no standardized method for characterization of traumatic aneurysms. For the carotid and vertebral injury study (CAVIS), a prospective study of traumatic cerebrovascular injury, we established a method for aneurysm characterization and tested its reliability. Saccular aneurysm size was defined as the greatest linear distance between the expected location of the normal artery wall and the outer edge of the aneurysm lumen ("depth"). Fusiform aneurysm size was defined as the "depth" and longitudinal distance ("length") paralleling the normal artery. The size of the aneurysm relative to the normal artery was also assessed. Reliability measurements were made using four raters who independently reviewed 15 computed tomographic angiograms (CTAs) and 13 digital subtraction angiograms (DSAs) demonstrating a traumatic aneurysm of the internal carotid artery. Raters categorized the aneurysms as either "saccular" or "fusiform" and made measurements. Five scans of each imaging modality were repeated to evaluate intra-rater reliability. Fleiss's free-marginal multi-rater kappa (κ), Cohen's kappa (κ), and interclass correlation coefficient (ICC) determined inter- and intra-rater reliability. Inter-rater agreement as to the aneurysm "shape" was almost perfect for CTA (κ = 0.82) and DSA (κ = 0.897). Agreements on aneurysm "depth," "length," "aneurysm plus parent artery," and "parent artery" for CTA and DSA were excellent (ICC > 0.75). Intra-rater agreement as to aneurysm "shape" was substantial to almost perfect (κ > 0.60). The CAVIS method of traumatic aneurysm characterization has remarkable inter- and intra-rater reliability and will facilitate further studies of the natural history and management of extracranial cerebrovascular traumatic aneurysms. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Computational Hemodynamic Analysis for the Diagnosis of Atherosclerotic Changes in Intracranial Aneurysms: A Proof-of-Concept Study Using 3 Cases Harboring Atherosclerotic and Nonatherosclerotic Aneurysms Simultaneously

PubMed Central

Endo, Hidenori; Niizuma, Kuniyasu; Endo, Toshiki; Funamoto, Kenichi; Ohta, Makoto; Tominaga, Teiji

2016-01-01

This was a proof-of-concept computational fluid dynamics (CFD) study designed to identify atherosclerotic changes in intracranial aneurysms. We selected 3 patients with multiple unruptured aneurysms including at least one with atherosclerotic changes and investigated whether an image-based CFD study could provide useful information for discriminating the atherosclerotic aneurysms. Patient-specific geometries were constructed from three-dimensional data obtained using rotational angiography. Transient simulations were conducted under patient-specific inlet flow rates measured by phase-contrast magnetic resonance velocimetry. In the postanalyses, we calculated time-averaged wall shear stress (WSS), oscillatory shear index, and relative residence time (RRT). The volume of blood flow entering aneurysms through the neck and the mean velocity of blood flow inside aneurysms were examined. We applied the age-of-fluid method to quantitatively assess the residence of blood inside aneurysms. Atherosclerotic changes coincided with regions exposed to disturbed blood flow, as indicated by low WSS and long RRT. Blood entered aneurysms in phase with inlet flow rates. The mean velocities of blood inside atherosclerotic aneurysms were lower than those inside nonatherosclerotic aneurysms. Blood in atherosclerotic aneurysms was older than that in nonatherosclerotic aneurysms, especially near the wall. This proof-of-concept study demonstrated that CFD analysis provided detailed information on the exchange and residence of blood that is useful for the diagnosis of atherosclerotic changes in intracranial aneurysms. PMID:27703491

Single Phase Dual-energy CT Angiography: One-stop-shop Tool for Evaluating Aneurysmal Subarachnoid Hemorrhage.

PubMed

Ni, Qian Qian; Tang, Chun Xiang; Zhao, Yan E; Zhou, Chang Sheng; Chen, Guo Zhong; Lu, Guang Ming; Zhang, Long Jiang

2016-05-25

Aneurysmal subarachnoid hemorrhages have extremely high case fatality in clinic. Early and rapid identifications of ruptured intracranial aneurysms seem to be especially important. Here we evaluate clinical value of single phase contrast-enhanced dual-energy CT angiograph (DE-CTA) as a one-stop-shop tool in detecting aneurysmal subarachnoid hemorrhage. One hundred and five patients who underwent true non-enhanced CT (TNCT), contrast-enhanced DE-CTA and digital subtraction angiography (DSA) were included. Image quality and detectability of intracranial hemorrhage were evaluated and compared between virtual non-enhanced CT (VNCT) images reconstructed from DE-CTA and TNCT. There was no statistical difference in image quality (P > 0.05) between VNCT and TNCT. The agreement of VNCT and TNCT in detecting intracranial hemorrhage reached 98.1% on a per-patient basis. With DSA as reference standard, sensitivity and specificity on a per-patient were 98.3% and 97.9% for DE-CTA in intracranial aneurysm detection. Effective dose of DE-CTA was reduced by 75.0% compared to conventional digital subtraction CTA. Thus, single phase contrast-enhanced DE-CTA is optimal reliable one-stop-shop tool for detecting intracranial hemorrhage with VNCT and intracranial aneurysms with DE-CTA with substantial radiation dose reduction compared with conventional digital subtraction CTA.

Single Phase Dual-energy CT Angiography: One-stop-shop Tool for Evaluating Aneurysmal Subarachnoid Hemorrhage

PubMed Central

Ni, Qian Qian; Tang, Chun Xiang; Zhao, Yan E; Zhou, Chang Sheng; Chen, Guo Zhong; Lu, Guang Ming; Zhang, Long Jiang

2016-01-01

Aneurysmal subarachnoid hemorrhages have extremely high case fatality in clinic. Early and rapid identifications of ruptured intracranial aneurysms seem to be especially important. Here we evaluate clinical value of single phase contrast-enhanced dual-energy CT angiograph (DE-CTA) as a one-stop-shop tool in detecting aneurysmal subarachnoid hemorrhage. One hundred and five patients who underwent true non-enhanced CT (TNCT), contrast-enhanced DE-CTA and digital subtraction angiography (DSA) were included. Image quality and detectability of intracranial hemorrhage were evaluated and compared between virtual non-enhanced CT (VNCT) images reconstructed from DE-CTA and TNCT. There was no statistical difference in image quality (P > 0.05) between VNCT and TNCT. The agreement of VNCT and TNCT in detecting intracranial hemorrhage reached 98.1% on a per-patient basis. With DSA as reference standard, sensitivity and specificity on a per-patient were 98.3% and 97.9% for DE-CTA in intracranial aneurysm detection. Effective dose of DE-CTA was reduced by 75.0% compared to conventional digital subtraction CTA. Thus, single phase contrast-enhanced DE-CTA is optimal reliable one-stop-shop tool for detecting intracranial hemorrhage with VNCT and intracranial aneurysms with DE-CTA with substantial radiation dose reduction compared with conventional digital subtraction CTA. PMID:27222163

Phase-contrast MRI versus numerical simulation to quantify hemodynamical changes in cerebral aneurysms after flow diverter treatment

PubMed Central

Frolov, Sergey; Prothmann, Sascha; Liepsch, Dieter; Balasso, Andrea; Berg, Philipp; Kaczmarz, Stephan; Kirschke, Jan Stefan

2018-01-01

Cerebral aneurysms are a major risk factor for intracranial bleeding with devastating consequences for the patient. One recently established treatment is the implantation of flow-diverters (FD). Methods to predict their treatment success before or directly after implantation are not well investigated yet. The aim of this work was to quantitatively study hemodynamic parameters in patient-specific models of treated cerebral aneurysms and its correlation with the clinical outcome. Hemodynamics were evaluated using both computational fluid dynamics (CFD) and phase contrast (PC) MRI. CFD simulations and in vitro MRI measurements were done under similar flow conditions and results of both methods were comparatively analyzed. For preoperative and postoperative distribution of hemodynamic parameters, CFD simulations and PC-MRI velocity measurements showed similar results. In both cases where no occlusion of the aneurysm was observed after six months, a flow reduction of about 30-50% was found, while in the clinically successful case with complete occlusion of the aneurysm after 6 months, the flow reduction was about 80%. No vortex was observed in any of the three models after treatment. The results are in agreement with recent studies suggesting that CFD simulations can predict post-treatment aneurysm flow alteration already before implantation of a FD and PC-MRI could validate the predicted hemodynamic changes right after implantation of a FD. PMID:29304062

Vascular Variations Associated with Intracranial Aneurysms.

PubMed

Orakdogen, Metin; Emon, Selin Tural; Somay, Hakan; Engin, Taner; Is, Merih; Hakan, Tayfun

2017-01-01

To investigate the vascular variations in patients with intracranial aneurysm in circle of Willis. We used the data on 128 consecutive intracranial aneurysm cases. Cerebral angiography images were analyzed retrospectively. Arteries were grouped as anterior cerebral arterial system (ACS), posterior cerebral arterial system (PCS) and middle cerebral arterial system (MCS) for grouping vascular variations. Lateralization, being single/multiple, gender; and also any connection with accompanying aneurysms" number, localization, dimension, whether bleeding/incidental aneurysm has been inspected. Variations were demonstrated in 57.8% of the cases. The most common variation was A1 variation (34.4%). The rate of variations was 36.7%, 24.2% and 10.2% respectively in ACS, PCS and MCS. MCS variations were significantly higher in males. Anterior communicating artery (ACoA) aneurysm observance rates were significantly higher and posterior communicating artery (PCoA) aneurysm and middle cerebral artery (MCA) aneurysm observance rates were significantly lower when compared to "no ACS variation detected" cases. In "PCS variation detected" cases, PCoA aneurysm observance rates and coexistence of multiple variations were significantly higher. The rate of vascular variations in patients with aneurysms was 57.8%. Arterial hypoplasia and aplasia were the most common variations. ACS was the most common region that variations were located in; they were mostly detected on the right side. Coexistence of ACoA aneurysm was higher than PCoA and MCA aneurysms. In the PCS variations group, PCoA aneurysms were the most common aneurysms that accompanying the variation and multiple variations were more common than in the other two groups. The variations in MCS were most common in males.

Three-dimensional morphological analysis of intracranial aneurysms: a fully automated method for aneurysm sac isolation and quantification.

PubMed

Larrabide, Ignacio; Cruz Villa-Uriol, Maria; Cárdenes, Rubén; Pozo, Jose Maria; Macho, Juan; San Roman, Luis; Blasco, Jordi; Vivas, Elio; Marzo, Alberto; Hose, D Rod; Frangi, Alejandro F

2011-05-01

Morphological descriptors are practical and essential biomarkers for diagnosis and treatment selection for intracranial aneurysm management according to the current guidelines in use. Nevertheless, relatively little work has been dedicated to improve the three-dimensional quantification of aneurysmal morphology, to automate the analysis, and hence to reduce the inherent intra and interobserver variability of manual analysis. In this paper we propose a methodology for the automated isolation and morphological quantification of saccular intracranial aneurysms based on a 3D representation of the vascular anatomy. This methodology is based on the analysis of the vasculature skeleton's topology and the subsequent application of concepts from deformable cylinders. These are expanded inside the parent vessel to identify different regions and discriminate the aneurysm sac from the parent vessel wall. The method renders as output the surface representation of the isolated aneurysm sac, which can then be quantified automatically. The proposed method provides the means for identifying the aneurysm neck in a deterministic way. The results obtained by the method were assessed in two ways: they were compared to manual measurements obtained by three independent clinicians as normally done during diagnosis and to automated measurements from manually isolated aneurysms by three independent operators, nonclinicians, experts in vascular image analysis. All the measurements were obtained using in-house tools. The results were qualitatively and quantitatively compared for a set of the saccular intracranial aneurysms (n = 26). Measurements performed on a synthetic phantom showed that the automated measurements obtained from manually isolated aneurysms where the most accurate. The differences between the measurements obtained by the clinicians and the manually isolated sacs were statistically significant (neck width: p <0.001, sac height: p = 0.002). When comparing clinicians' measurements to automatically isolated sacs, only the differences for the neck width were significant (neck width: p <0.001, sac height: p = 0.95). However, the correlation and agreement between the measurements obtained from manually and automatically isolated aneurysms for the neck width: p = 0.43 and sac height: p = 0.95 where found. The proposed method allows the automated isolation of intracranial aneurysms, eliminating the interobserver variability. In average, the computational cost of the automated method (2 min 36 s) was similar to the time required by a manual operator (measurement by clinicians: 2 min 51 s, manual isolation: 2 min 21 s) but eliminating human interaction. The automated measurements are irrespective of the viewing angle, eliminating any bias or difference between the observer criteria. Finally, the qualitative assessment of the results showed acceptable agreement between manually and automatically isolated aneurysms.

[Congenital anomalies of cerebral artery and intracranial aneurysm].

PubMed

Nakajima, K; Ito, Z; Hen, R; Uemura, K; Matsuoka, S

1976-02-01

It is well known that congenital anomalies such as polycystic kidney, aortic coarctation, Marfan syndrome, Ehler-Danlos syndrome are apt to be complicated by intracranial aneurysms. In this report we attempt to reveal the relation and incidence between cerebrovascular anomalies and intracranial aneurysms. The etiology of aneurysms has been discussed, too. 12 cases of persistent trigeminl artery, 2 cases of persistent hypoglossal artery and 11 cases of fenestration were obtained from 3841 patients who were angiographically examined in our clinic for 5 years. The incidence is 0.31%, 0.05% and 0.29%, respectively. Persistent trigeminal arteries were complicated by 2 cases of intracranial aneurysms and one case of arterivenous malformations (AVM), persistent hypoglossal arteries were complicated by one case of aneurysm, and fenestrations were complicated by 2 cases of aneurysms and one case of AVM. One case of congenital agenesis of right internal carotid artery was obtained which was complicated by aneurysm of anterior communicating artery. Totally, 8 cases of aneurysms and AVM were obtained from 26 cases of cerebrovascular anomalies (incidence 30.8%). On the other hand, thalamic or caudate hemorrhage revealed the highest incidence of complication of intracranial aneurysms among intracerebral hematomas (10.7%). Compared with the incidence of aneurysms between cerebro vascular anomalies (30.8%) and thalamic or caudate hemorrhage (10.7%), the difference is statistically signigicant (P less than 0.05). The cause of intracranial aneurysm has not yet been clarified. But it is well accepted that the defect of tunica media vasorum is most responsible factor as to the occurrence of intracranial aneurysms. We concluded that the genetic error of cerebral vessels including defect of media caused intracranial aneurysms, and this result was supported from the evidence that cerebrovascular anomalies showed statistically high incidence of complication of intracranial aneurysms.

Aneurysm miRNA Signature Differs, Depending on Disease Localization and Morphology

PubMed Central

Busch, Albert; Busch, Martin; Scholz, Claus-Jürgen; Kellersmann, Richard; Otto, Christoph; Chernogubova, Ekaterina; Maegdefessel, Lars; Zernecke, Alma; Lorenz, Udo

2016-01-01

Limited comprehension of aneurysm pathology has led to inconclusive results from clinical trials. miRNAs are key regulators of post-translational gene modification and are useful tools in elucidating key features of aneurysm pathogenesis in distinct entities of abdominal and popliteal aneurysms. Here, surgically harvested specimens from 19 abdominal aortic aneurysm (AAA) and 8 popliteal artery aneurysm (PAA) patients were analyzed for miRNA expression and histologically classified regarding extracellular matrix (ECM) remodeling and inflammation. DIANA-based computational target prediction and pathway enrichment analysis verified our results, as well as previous ones. miRNA-362, -19b-1, -194, -769, -21 and -550 were significantly down-regulated in AAA samples depending on degree of inflammation. Similar or inverse regulation was found for miR-769, 19b-1 and miR-550, -21, whereas miR-194 and -362 were unaltered in PAA. In situ hybridization verified higher expression of miR-550 and -21 in PAA compared to AAA and computational analysis for target genes and pathway enrichment affirmed signal transduction, cell-cell-interaction and cell degradation pathways, in line with previous results. Despite the vague role of miRNAs for potential diagnostic and treatment purposes, the number of candidates from tissue signature studies is increasing. Tissue morphology influences subsequent research, yet comparison of distinct entities of aneurysm disease can unravel core pathways. PMID:26771601

Evaluating of small intracranial aneurysms by 64-detector CT Angiography: a comparison with 3-dimensional rotation DSA or surgical findings.

PubMed

Zhang, He; Hou, Chang; Zhou, Zhi; Zhang, Hao; Zhou, Gen; Zhang, Gui

2014-01-01

The diagnostic performance of 64-detector computed tomographic angiography (CTA) for detection of small intracranial aneurysms (SIAs) was evaluated. In this prospective study, 112 consecutive patients underwent 64-detector CTA before volume-rendering rotation digital subtraction angiography (VR-RDSA) or surgery. VR-RDSA or intraoperative findings or both were used as the gold standards. The accuracy, sensitivity, specificity, and positive predictive values (PPV) and negative predictive values (NPV), as measures to detect or rule out SIAs, were determined by patient-based and aneurysm size-based evaluations. The reference standard methods revealed 84 small aneurysms in 71 patients. The results of patient-based 64-detector CTA evaluation for SIAs were: accuracy, 98.2%; sensitivity, 98.6%; specificity, 97.6%; PPV, 98.6%; and NPV, 97.6%. The aneurysm-based evaluation results were: accuracy, 96.8%; sensitivity, 97.6%; specificity, 95.1%; PPV, 97.6%; and NPV, 95.1%. Two false-positive and two false-negative findings for aneurysms <3 mm in size occurred in the 64-detector CTA analysis. The diagnostic performance of 64-detector CTA did not improve much compared with 16-detector CTA for detecting SIAs, especially for very small aneurysms. VR-RDSA is still necessary for patients with a history of subarachnoid hemorrhage if the CTA findings are negative. Copyright © 2012 by the American Society of Neuroimaging.

Recombinant human SDF-1α administration accelerates aneurysm neck reendothelialization in rabbit saccular aneurysm after flow diverter treatment.

PubMed

Li, Zifu; Zhao, Rui; Fang, Xinggen; Huang, Qinghai; Liu, Jianmin

2017-03-01

Reendothelialization in the aneurysm neck is pivotal to vascular repair for intracranial aneurysm after flow diverter (FD) implantation. Recombinant human stromal cell-derived factor 1α (rhSDF-1α) is a vital chemoattractant to stem cells and potentially facilitates reendothelialization. Here, we sought to investigate the therapeutic effects of intravenous administration of rhSDF-1α and uncover its potential mechanism for promoting aneurysm neck reendothelialization. Recombinant pET32a-186 plasmid was transformed into Escherichia coli to produce the rhSDF-1α protein with biological activity. FD was implanted into the elastase-induced saccular aneurysm in New Zealand white rabbits. rhSDF-1α (50 μg/kg/day) was intravenously administrated for consecutive 7 days after FD implantation. After these procedures, aneurysms were harvested after 2 or 4 weeks. Scanning electron microscopy was used to measure the neointima thickness and count the endothelial-like cells at aneurysm neck. Four weeks later, the mRNA levels of endothelial markers in the neointima at aneurysm neck were examined. Migration assay showed that rhSDF-1α could induce migration of endothelial progenitor cells in a dose-dependent manner. Two weeks after stent implantation, follow-up angiography showed partial aneurysm occlusion in one of each group and total aneurysm occlusion in 17 saccular aneurysm rabbits (9 of the rhSDF-1α group and 8 of the control group). No significant change of neointima thickness at aneurysm neck was observed. Intriguingly, more endothelial-like cells were observed at aneurysm neck in the rhSDF-1α group at 2 weeks (55 vs 13 cells per high-power field) and 4 weeks (104 vs 60 cells per high-power field). The mRNA levels of Tie-2, VE-cadherin, KDR and E-selectin were significantly enhanced compared with those of the control group. These results showed that intravenous administration of rhSDF-1α can accelerate reendothelialization in the aneurysm neck after FD implantation. Our study reveals an important role of rhSDF-1α in inducing aneurysm occlusion and suggests that it achieves its function through modulating the reendothelialization. © The Author 2017. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Aortic Wall Inflammation Predicts Abdominal Aortic Aneurysm Expansion, Rupture, and Need for Surgical Repair

PubMed Central

2017-01-01

Background: Ultrasmall superparamagnetic particles of iron oxide (USPIO) detect cellular inflammation on magnetic resonance imaging (MRI). In patients with abdominal aortic aneurysm, we assessed whether USPIO-enhanced MRI can predict aneurysm growth rates and clinical outcomes. Methods In a prospective multicenter open-label cohort study, 342 patients with abdominal aortic aneurysm (diameter ≥40 mm) were classified by the presence of USPIO enhancement and were monitored with serial ultrasound and clinical follow-up for ≥2 years. The primary end point was the composite of aneurysm rupture or repair. Results Participants (85% male, 73.1±7.2 years) had a baseline aneurysm diameter of 49.6±7.7 mm, and USPIO enhancement was identified in 146 (42.7%) participants, absent in 191 (55.8%), and indeterminant in 5 (1.5%). During follow-up (1005±280 days), 17 (5.0%) abdominal aortic aneurysm ruptures, 126 (36.8%) abdominal aortic aneurysm repairs, and 48 (14.0%) deaths occurred. Compared with those without uptake, patients with USPIO enhancement have increased rates of aneurysm expansion (3.1±2.5 versus 2.5±2.4 mm/year, P=0.0424), although this was not independent of current smoking habit (P=0.1993). Patients with USPIO enhancement had higher rates of aneurysm rupture or repair (47.3% versus 35.6%; 95% confidence intervals, 1.1–22.2; P=0.0308). This finding was similar for each component of rupture (6.8% versus 3.7%, P=0.1857) or repair (41.8% versus 32.5%, P=0.0782). USPIO enhancement was associated with reduced event-free survival for aneurysm rupture or repair (P=0.0275), all-cause mortality (P=0.0635), and aneurysm-related mortality (P=0.0590). Baseline abdominal aortic aneurysm diameter (P<0.0001) and current smoking habit (P=0.0446) also predicted the primary outcome, and the addition of USPIO enhancement to the multivariate model did not improve event prediction (c-statistic, 0.7935–0.7936). Conclusions USPIO-enhanced MRI is a novel approach to the identification of aortic wall cellular inflammation in patients with abdominal aortic aneurysms and predicts the rate of aneurysm growth and clinical outcome. However, it does not provide independent prediction of aneurysm expansion or clinical outcomes in a model incorporating known clinical risk factors. Clinical Trial Registration: URL: http://www.isrctn.com. Unique identifier: ISRCTN76413758. PMID:28720724

Unruptured cerebral aneurysms do not shrink when they rupture: multicenter collaborative aneurysm study group.

PubMed

Rahman, Maryam; Ogilvy, Christopher S; Zipfel, Gregory J; Derdeyn, Colin P; Siddiqui, Adnan H; Bulsara, Ketan R; Kim, Louis J; Riina, Howard A; Mocco, J; Hoh, Brian L

2011-01-01

The International Study of Intracranial Aneurysms found that for patients with no previous history of subarachnoid hemorrhage, small (< 7 mm) anterior circulation and posterior circulation aneurysms had a 0% and 2.5% risk of subarachnoid hemorrhage over 5 years, respectively. To determine whether cerebral aneurysms shrink with rupture. The clinical databases of 7 sites were screened for patients with imaging of cerebral aneurysms before and after rupture. Inclusion criteria included documented subarachnoid hemorrhage by imaging or lumbar puncture and intracranial imaging before and after cerebral aneurysm rupture. The patients were evaluated for aneurysm maximal height, maximal width, neck diameter, and other measurement parameters. Only a change of ≥ 2 mm was considered a true change. Data on 13 patients who met inclusion criteria were collected. The median age was 60, and 11 of the 13 patients (84.6%) were female. Only 5 patients had posterior circulation aneurysms. None of the aneurysms had a significant decrease in size. One aneurysm decreased by 1.8 mm in maximum size after rupture (7.7%). Six aneurysms had an increase in maximum size of at least 2 mm after rupture (46.2%) with a mean increase of 3.5 mm (± 0.5 mm). Unruptured aneurysms do not shrink when they rupture. The large percentage of ruptured small aneurysms in previous studies were likely small before they ruptured.

Blood flow characteristics in a terminal basilar tip aneurysm prior to its fatal rupture

PubMed Central

Sforza, D.M.; Putman, C.M.; Scrivano, E.; Lylyk, P.; Cebral, J.R.

2010-01-01

Background and Purpose The development and validation of methods to stratify the risk of rupture of cerebral aneurysms is highly desired since current treatment risks can exceed the natural risk of rupture. Because unruptured aneurysms are typically treated before they rupture, it is very difficult to connect the proposed risk indices to the rupture of an individual aneurysm. The purpose of this case study was to analyze the hemodynamic environment of a saccular aneurysm of the terminal morphology sub-type that was imaged just prior to its rupture and to test whether the hemodynamic characteristics would designate this particular aneurysm as at high risk. Methods A patient-specific computational fluid dynamics model was constructed from 3D rotational angiography images acquired just hours before the aneurysm ruptured. A pulsatile flow calculation was performed and hemodynamic characteristics previously connected to rupture were analyzed. Results It was found that the aneurysm had a concentrated inflow stream, small impingement region, complex intra-aneurysmal flow structure, asymmetric flow split from the parent vessel to the aneurysm and daughter branches, and high levels of aneurysmal wall shear stress near the impaction zone. Conclusions The hemodynamics characteristics observed in this aneurysm right before its rupture are consistent with previous studies correlating aneurysm rupture and hemodynamic patterns in saccular and terminal aneurysms. This study supports the notion that hemodynamic information may be used to help stratify the rupture risk of cerebral aneurysms. PMID:20150312

Recovery to Preinterventional Functioning, Return-to-Work, and Life Satisfaction After Treatment of Unruptured Aneurysms.

PubMed

Backes, Daan; Rinkel, Gabriel J E; van der Schaaf, Irene C; Nij Bijvank, Jenny A; Verweij, Bon H; Visser-Meily, Johanna M A; Post, Marcel W; Algra, Ale; Vergouwen, Mervyn D I

2015-06-01

The eventual goal of preventive treatment of unruptured intracranial aneurysms is to increase the number of life years with high life satisfaction. Insight in the time with reduced functioning, working capacity, and life satisfaction after aneurysm treatment is pivotal to balance the pros and cons of preventive aneurysm occlusion. We sent a questionnaire on time-to-recovery to preintervention functioning and return-to-work and life satisfaction to patients treated for an unruptured aneurysm between 2000 and 2013. Changes in life satisfaction before treatment, during recovery, and at follow-up were assessed with Wilcoxon signed-rank tests. The questionnaire was sent to 159 patients of whom 110 (69%) responded. The mean follow-up time after aneurysm treatment was 6 years (SD 4). Fifty-four patients had endovascular and 56 had microsurgical occlusion. Complete recovery to preintervention functioning was reported by 81% (95% confidence interval [CI], 74-88) of patients, with a median time-to-recovery of 3 months (range 0-48). Complete work recovery was reported by 78% (95% CI, 66-87) of patients. The proportion of patients with high life satisfaction reduced from 76% (95% CI, 67-84) before treatment to 52% (95% CI, 43-61) during the period of recovery (P<0.01) and restored largely at long-term follow-up (67% [95% CI, 59-76], P=0.08). Life satisfaction is significantly reduced during the period of recovery after treatment of unruptured aneurysms. In the long-term, ≈1 out of 5 patients reports incomplete recovery. These treatment effects should be kept in mind when considering preventive aneurysm treatment. Prospective studies are needed to better compare these losses in patients treated for unruptured aneurysms with those who had subarachnoid hemorrhage. © 2015 American Heart Association, Inc.

Follow-up assessment of coiled intracranial aneurysms using zTE MRA as compared with TOF MRA: a preliminary image quality study.

PubMed

Shang, Song'an; Ye, Jing; Luo, Xianfu; Qu, Jianxun; Zhen, Yong; Wu, Jingtao

2017-10-01

To prospectively assess coiled intracranial aneurysms using a novel non-contrast enhanced zero echo time (zTE) MR angiography (MRA) method, and compare its image quality with time-of-flight (TOF) MRA, using digital subtraction angiography (DSA) as reference. Twenty-five patients (10 males and 15 females; age 53.96 ± 12.46 years) were enrolled in this monocentric study. MRA sequences were performed 24 h before DSA. Susceptibility artefact intensity and flow signal within the parent artery were carried out using a 4-point scale. Occlusion status was assessed using the 3-grade Montreal scale. Scores of zTE were higher than TOF for both susceptibility artefact intensity (3.42 ± 0.64, 2.92 ± 0.63, P = 0.01) and flow signal (3.66 ± 0.95, 3.24 ± 1.24, P = 0.01). DSA revealed 17 complete occlusions, five residual neck aneurysms and two residual aneurysms. Inter-observer agreement was excellent (weighted κ: 0.89) for zTE and good (weighted κ: 0.68) for TOF. Intermodality agreement was excellent for zTE (weighted κ: 0.95) and good for TOF (weighted κ: 0.80). Correlations of both MRA sequences with DSA were high (zTE, Spearman's ρ: 0.91; TOF, Spearman's ρ: 0.81). zTE MRA showed promising results for follow-up assessment of coiled intracranial aneurysms and was superior to TOF MRA for visualizing the parent artery and evaluating occlusion status. • Various MRA sequences were applied for follow-up assessment of coiled intracranial aneurysms. • zTE MRA was less sensitive to susceptibility artefacts and haemodynamics. • In this monocentric study, zTE MRA was equivalent to DSA. • zTE MRA maybe an alternative to TOF MRA for follow-up assessment.

Diagnostic performance of focused cardiac ultrasound performed by emergency physicians for the assessment of ascending aorta dilation and aneurysm.

PubMed

Nazerian, Peiman; Vanni, Simone; Morello, Fulvio; Castelli, Matteo; Ottaviani, Maddalena; Casula, Claudia; Petrioli, Alessandra; Bartolucci, Maurizio; Grifoni, Stefano

2015-05-01

The diagnostic performance of transthoracic focused cardiac ultrasound (FoCUS) performed by emergency physicians (EP) to estimate ascending aorta dimensions in the acute setting has not been prospectively studied. The diagnostic accuracy and the interobserver variability of EP-performed FoCUS were investigated to estimate thoracic aortic dilation and aneurysm compared with the results of computed tomography angiography (CTA). This was a prospective single-center cohort study of a convenience sample of patients who underwent CTA in the emergency department for suspected aortic pathology. FoCUS was performed before CTA, and the maximum ascending aorta diameter evaluated in parasternal long-axis view. Aorta diameter < 40 mm by visual estimation or by diameter measurement was considered normal. Measurements were recorded in all patients with aorta diameter ≥ 40 mm. Diagnostic accuracy of FoCUS for detection of aortic dilation (diameter ≥ 40 mm) and aneurysm (diameter ≥ 45 mm) were calculated considering the CTA result as reference standard. In a subgroup of patients, a second EP-sonographer performed FoCUS to evaluate interobserver agreement for the diagnosis of ascending aorta dilation. A total of 140 patients were enrolled in the study. Ascending aorta dilation and aneurysm were detected with FoCUS in 50 (35.7%) and in 27 (17.8%) patients, respectively. Sensitivity and specificity of FoCUS were 78.6% (95% confidence interval [CI] = 65.6% to 88.4%) and 92.9% (95% CI = 85.1% to 97.3%), respectively, for ascending aorta dilation and 64.7% (95% CI = 46.5% to 80.2%) and 95.3% (95% CI = 89.3% to 98.4%), respectively, for ascending aorta aneurysm. Interobserver agreement of FoCUS was k = 0.82. FoCUS performed by EP is specific for ascending aorta dilation and aneurysm when compared to CTA and appears a reproducible technique. © 2015 by the Society for Academic Emergency Medicine.

Medical Management of Small Abdominal Aortic Aneurysms

PubMed Central

Baxter, B. Timothy; Terrin, Michael C.; Dalman, Ronald L.

2013-01-01

Abdominal aortic aneurysm is a common condition that may be lethal when it is unrecognized. Current guidelines suggest repair as the aneurysm diameter reaches 5.0 to 5.5 cm. Most aortic aneurysms are detected incidentally when imaging is done for other purposes or through screening programs. Ninety percent of these aneurysms are below the threshold for intervention at the time of detection. A number of studies have sought to determine factors that lead to progression of aneurysmal disease that might be amenable to intervention during this period of observation. We review these studies and make recommendations for the medical management of small abdominal aortic aneurysms. On the basis of our current knowledge of the causes of aneurysm, a number of approaches have been proposed to prevent progression of aneurysmal disease. These include hemodynamic management, inhibition of inflammation, and protease inhibition. The American College of Cardiology/American Heart Association clinical practice guidelines rules of evidence have helped to define strength of evidence to support these approaches. Level A evidence (from large randomized trials) is available to indicate that observation of small aneurysms in men is safe up to a size of 5.5 cm and that propranolol does not inhibit aneurysm expansion. Level B evidence (from small randomized trials) suggests that roxithromycin or doxycycline will decrease the rate of aneurysm expansion. A number of studies agree that tobacco use is associated with an increased rate of aneurysm expansion. Level B and C evidence is available to suggest that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) may inhibit aneurysm expansion. There are animal data but no human data demonstrating that angiotensin-converting enzyme inhibitors or losartan, an angiotensin receptor blocker, will decrease the rate of AAA expansion. A pharmacological agent without important side effects that inhibited aneurysm expansion could change current approaches to aneurysm treatment. Additional studies are needed to clarify the potential role of doxycycline, roxithromycin, and statin therapy in the progression of aneurysmal disease. PMID:18391122

Incidence of periodontitis in Japanese patients with cardiovascular diseases: a comparison between abdominal aortic aneurysm and arrhythmia.

PubMed

Suzuki, Jun-Ichi; Aoyama, Norio; Aoki, Mieko; Tada, Yuko; Wakayama, Kouji; Akazawa, Hiroshi; Shigematsu, Kunihiro; Hoshina, Katsuyuki; Izumi, Yuichi; Komuro, Issei; Miyata, Tetsuro; Hirata, Yasunobu; Isobe, Mitsuaki

2015-07-01

Although there is a link between periodontitis and cardiovascular disease (CVD), the influence of periodontitis on CVD is unclear. The aim of this study was to assess the relationship between periodontal bacterial burden and CVD. We studied 142 patients with tachyarrhythmia (TA) and 25 patients with abdominal aortic aneurysm (AAA). We examined periodontitis and the presence of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans and Prevotella intermedia in the patients' saliva and subgingival plaque using PCR. We also measured serum antibody titers against the pathogens using ELISA. We found that the patients with AAA had fewer remaining teeth (14.6 ± 2.0 vs. 20.9 ± 0.7, P < 0.05) and deeper pocket depth (3.01 ± 0.26 vs. 2.52 ± 0.05 mm, P < 0.05) compared to the TA patients. The existence of each periodontal bacterium in their saliva or subgingival plaque and serum antibody titers was comparable between the two groups. Periodontitis may have a larger affect on aneurysm progression compared to arrhythmia.

Visualization of the aneurysm wall: a 7.0-tesla magnetic resonance imaging study.

PubMed

Kleinloog, Rachel; Korkmaz, Emine; Zwanenburg, Jaco J M; Kuijf, Hugo J; Visser, Fredy; Blankena, Roos; Post, Jan A; Ruigrok, Ynte M; Luijten, Peter R; Regli, Luca; Rinkel, Gabriel J E; Verweij, Bon H

2014-12-01

Risk prediction of rupture of intracranial aneurysms is poor and is based mainly on lumen characteristics. However, characteristics of the aneurysm wall may be more informative predictors. The limited resolution of currently available imaging techniques and the thin aneurysm wall make imaging of wall thickness challenging. To introduce a novel protocol for imaging wall thickness variation using ultra--high-resolution 7.0-Tesla (7.0-T) magnetic resonance imaging (MRI). We studied 33 unruptured intracranial aneurysms in 24 patients with a T1-weighted 3-dimensional magnetization-prepared inversion-recovery turbo-spin-echo whole-brain sequence with a resolution of 0.8 × 0.8 × 0.8 mm. We performed a validation study with a wedge phantom and with 2 aneurysm wall biopsies obtained during aneurysm treatment using ex vivo MRI and histological examination and correlating variations in MRI signal intensity with variations in actual thickness of the aneurysm wall. In vivo, the aneurysm wall was visible in 28 of the 33 aneurysms. Variation in signal intensity was observed in all visible aneurysm walls. Ex vivo MRI showed variation in signal intensity across the wall of the biopsies, similar to that observed on the in vivo images. Signal intensity and actual thickness in both biopsies had a linear correlation, with Pearson correlation coefficients of 0.85 and 0.86. Unruptured intracranial aneurysm wall and its variation in thickness can be visualized with 7.0-T MRI. Aneurysm wall thickness variation can now be further studied as a risk factor for rupture in prospective studies.

A failure to communicate: patients with cerebral aneurysms and vascular neurosurgeons

PubMed Central

King, J; Yonas, H; Horowitz, M; Kassam, A; Roberts, M

2005-01-01

Objective: To assess communication between vascular neurosurgeons and their patients with unruptured cerebral aneurysms about treatment options and expected outcomes. Methods: Vascular neurosurgeons and their patients with cerebral aneurysms were surveyed immediately following outpatient appointments in a neurosurgery clinic. Data collected included how well the patient understood their aneurysm treatment options, the risks of a poor outcome from various treatments, and the consensus "best" treatment. Patient and neurosurgeon responses were measured using Likert scales, multiple choice questions, and visual analogue scales. Agreement between patient and neurosurgeon was assessed with kappa scores. The Wilcoxon sign rank test was used to compare visual analogue scale responses. Results: Data for 44 patient–neurosurgeon pairs were collected. Only 61% of patient–neurosurgeon pairs agreed on the best treatment plan for the patient's aneurysm (κ = 0.51, moderate agreement). Among the neurosurgeons, agreement with their patients ranged from 82% (κ = 0.77, almost perfect agreement) to 52% (κ = 0.37, fair agreement). Patients estimated much higher risks of stroke or death from surgical clipping, endovascular embolisation, or no intervention compared with the estimates offered by their neurosurgeons (surgical clipping: patient 36% v neurosurgeon 13%, p<0.001; endovascular embolisation: patient 35% v neurosurgeon 19%, p = 0.040; and no intervention: patient 63% v neurosurgeon 25%, p<0.001). Conclusions: Following consultation with a vascular neurosurgeon, many patients with cerebral aneurysms have an inaccurate understanding of their aneurysm treatment plan and an exaggerated sense of the risks of aneurysmal disease and treatment. PMID:15774444

A failure to communicate: patients with cerebral aneurysms and vascular neurosurgeons.

PubMed

King, J T; Yonas, H; Horowitz, M B; Kassam, A B; Roberts, M S

2005-04-01

To assess communication between vascular neurosurgeons and their patients with unruptured cerebral aneurysms about treatment options and expected outcomes. Vascular neurosurgeons and their patients with cerebral aneurysms were surveyed immediately following outpatient appointments in a neurosurgery clinic. Data collected included how well the patient understood their aneurysm treatment options, the risks of a poor outcome from various treatments, and the consensus "best" treatment. Patient and neurosurgeon responses were measured using Likert scales, multiple choice questions, and visual analogue scales. Agreement between patient and neurosurgeon was assessed with kappa scores. The Wilcoxon sign rank test was used to compare visual analogue scale responses. Data for 44 patient-neurosurgeon pairs were collected. Only 61% of patient-neurosurgeon pairs agreed on the best treatment plan for the patient's aneurysm (kappa = 0.51, moderate agreement). Among the neurosurgeons, agreement with their patients ranged from 82% (kappa = 0.77, almost perfect agreement) to 52% (kappa = 0.37, fair agreement). Patients estimated much higher risks of stroke or death from surgical clipping, endovascular embolisation, or no intervention compared with the estimates offered by their neurosurgeons (surgical clipping: patient 36% v neurosurgeon 13%, p<0.001; endovascular embolisation: patient 35% v neurosurgeon 19%, p = 0.040; and no patient 63% v neurosurgeon 25%, p<0.001). Following consultation with a vascular neurosurgeon, many patients with cerebral aneurysms have an inaccurate understanding of their aneurysm treatment plan and an exaggerated sense of the risks of aneurysmal disease and treatment.

Assessment of hemodynamics of intracranial aneurysms using Doppler optical coherence tomography in patient specific phantoms: preliminary results (Conference Presentation)

NASA Astrophysics Data System (ADS)

Ramjist, Joel M.; Jivraj, Jamil; Barrows, Dexter; Vuong, Barry; Wong, Ronnie; Yang, Victor X. D.

2017-02-01

Intracranial aneurysms affect a large number of individuals every year. Changes to hemodynamics are thought to be a crucial factor in the initial formation and enlargement of intracranial aneurysms. Previously, surgical clipping - an open an invasive procedure, was the standard of care. More recently, minimally invasive, catheter based therapies, specifically stenting and coiling, has been employed for treatment as it is less invasive and poses fewer overall risks. However, these treatments can further alter hemodynamic patterns of patients, affecting efficacy and prognosis. Doppler optical coherence tomography (DOCT) has shown to be useful for the evaluation of changes to hemodynamic patterns in various vascular pathologies, and intravascular DOCT may provide useful insight in the evaluation and changes to hemodynamic patterns before and during the treatment of aneurysms. In this study, we present preliminary results of DOCT imaging used in three patient-specific aneurysm phantoms located within the Circle of Willis both pre and post-treatment. These results are compared with computational fluid dynamics (CFD) simulations and high-speed camera imaging for further interpretation and validation of results.

Analysis and quantification of endovascular coil distribution inside saccular aneurysms using histological images.

PubMed

Morales, Hernán G; Larrabide, Ignacio; Geers, Arjan J; Dai, Daying; Kallmes, David F; Frangi, Alejandro F

2013-11-01

Endovascular coiling is often performed by first placing coils along the aneurysm wall to create a frame and then by filling up the aneurysm core. However, little attention has been paid to quantifying this filling strategy and to see how it changes for different packing densities. The purpose of this work is to analyze and quantify endovascular coil distribution inside aneurysms based on serial histological images of experimental aneurysms. Seventeen histological images from 10 elastase-induced saccular aneurysms in rabbits treated with coils were studied. In-slice coil density, defined as the area taken up by coil winds, was calculated on each histological image. Images were analyzed by partitioning the aneurysm along its longitudinal and radial axes. Coil distribution was quantified by measuring and comparing the in-slice coil density of each partition. Mean total in-slice coil density was 22.0 ± 6.2% (range 10.1-30.2%). The density was non-significantly different (p = 0.465) along the longitudinal axis. A significant difference (p < 0.001) between peripheral and core densities was found. Additionally, the peripheral-core density ratio was observed to be inversely proportional to the total in-slice coil density (R(2)=0.57, p <0.001). This ratio was near unity for high in-slice coil density (around 30%). These findings demonstrate and confirm that coils tend to be located near the aneurysm periphery when few are inserted. However, when more coils are added, the radial distribution becomes more homogeneous. Coils are homogeneously distributed along the longitudinal axis.

Characterizing saccular aortic arch aneurysms from the geometry-flow dynamics relationship.

PubMed

Natsume, Kayoko; Shiiya, Norihiko; Takehara, Yasuo; Sugiyama, Masataka; Satoh, Hiroshi; Yamashita, Katsushi; Washiyama, Naoki

2017-06-01

Low wall shear stress (WSS) has been reported to be associated with accelerated atherosclerosis, aneurysm growth, or rupture. We evaluated the geometry of aortic arch aneurysms and their relationship with WSS by using the 4-dimensional flow magnetic resonance imaging to better characterize the saccular aneurysms. We analyzed the geometry in 100 patients using multiplanar reconstruction of computed tomography. We evaluated WSS and vortex flow using 4-dimensional flow magnetic resonance imaging in 16 of them, which were compared with 8 age-matched control subjects and eight healthy young volunteers. Eighty-two patients had a saccular aneurysm, and 18 had a fusiform aneurysm. External diameter/aneurysm length ratio and sac depth/neck width ratio of the fusiform aneurysms were constant at 0.76 ± 0.18 and 0.23 ± 0.09, whereas those of saccular aneurysms, especially those involving the outer curvature, were higher and more variable. Vortex flow was always present in the aneurysms, resulting in low WSS. When the sac depth/neck width ratio was less than 0.8, peak WSS correlated inversely with luminal diameter even in the saccular aneurysms. When this ratio exceeded 0.8, which was the case only with the saccular aneurysms, such correlation no longer existed and WSS was invariably low. Fusiform aneurysms elongate as they dilate, and WSS is lower as the diameter is larger. Saccular aneurysms dilate without proportionate elongation, and they, especially those occupying the inner curvature, have higher and variable sac depth/neck width ratio. When this ratio exceeds 0.8, WSS is low regardless of diameter, which may explain their malignant clinical behavior. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

Patient-reported outcome measures for patients with cerebral aneurysms acquired via social media: data from a large nationwide sample.

PubMed

Chen, Michael; Mangubat, Erwin; Ouyang, Bichun

2016-01-01

With greater survival rates, patient-reported outcome measures (PROMs) among survivors of ruptured cerebral aneurysm should be an increasing concern among neurointerventionalists. Prior studies were limited in scale and generalizability. Our study aims were to (1) evaluate the validity of cerebral aneurysm PROMs obtained from social media; (2) determine the persistence of PROMs over time; and (3) determine what PROMs still exist in those with no physical impairments. By engaging national brain aneurysm support groups and using an online questionnaire modeled after the generic EQ-5D instrument, we asked respondents to classify their health in five dimensions including mobility, self-care, usual activities, pain/discomfort, and anxiety/depression using a 3-point Likert scale. In 2 months we received 604 responses from 46 states in the USA. Our cohort of ruptured aneurysm respondents reported PROMs similar to previously published series. Over time, headache and anxiety improved while depression, level of exercise, and return to work remained unchanged. We found that memory worsened after 2 years. Among those without any physical impairment, rates of 20.6%, 14.9%, 12.6%, and 23% were seen for significant headaches, significant memory loss, significant depression, and sense of life being negatively affected, respectively. Despite this novel study design, we obtained results comparable to prior studies. These results suggest that many patients with ruptured cerebral aneurysms, regardless of whether they are >2 years after the event and/or free of physical impairment, struggle with a poor quality of life. The latency, scale, and low cost of this study design may accelerate future cerebral aneurysm PROM research. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Isolated abducens nerve palsy associated with subarachnoid hemorrhage: a localizing sign of ruptured posterior inferior cerebellar artery aneurysms.

PubMed

Burkhardt, Jan-Karl; Winkler, Ethan A; Lasker, George F; Yue, John K; Lawton, Michael T

2018-06-01

OBJECTIVE Compressive cranial nerve syndromes can be useful bedside clues to the diagnosis of an enlarging intracranial aneurysm and can also guide subsequent evaluation, as with an acute oculomotor nerve (cranial nerve [CN] III) palsy that is presumed to be a posterior communicating artery aneurysm and a surgical emergency until proven otherwise. The CN VI has a short cisternal segment from the pontomedullary sulcus to Dorello's canal, remote from most PICA aneurysms but in the hemodynamic pathway of a rupturing PICA aneurysm that projects toward Dorello's canal. The authors describe a cranial nerve syndrome for posterior inferior cerebellar artery (PICA) aneurysms that associates subarachnoid hemorrhage (SAH) and an isolated abducens nerve (CN VI) palsy. METHODS Clinical and radiological data from 106 surgical patients with PICA aneurysms (66 ruptured and 40 unruptured) were retrospectively reviewed. Data from a group of 174 patients with other aneurysmal SAH (aSAH) were analyzed in a similar manner to control for nonspecific effects of SAH. Univariate statistical analysis compared incidence and risk factors associated with CN VI palsy in subarachnoid hemorrhage. RESULTS Overall, 13 (4.6%) of 280 patients had CN VI palsy at presentation, and all of them had ruptured aneurysms (representing 13 [5.4%] of the 240 cases of ruptured aneurysms). CN VI palsies were observed in 12 patients with ruptured PICA aneurysms (12/66 [18.1%]) and 1 patient with other aSAH (1/174 [0.1%], p < 0.0001). PICA aneurysm location in ruptured aneurysms was an independent predictor for CN VI palsy on multivariate analysis (p = 0.001). PICA aneurysm size was not significantly different in patients with or without CN VI palsy (average size 4.4 mm and 5.2 mm, respectively). Within the PICA aneurysm cohort, modified Fisher grade (p = 0.011) and presence of a thick cisternal SAH (modified Fisher Grades 3 and 4) (p = 0.003) were predictors of CN VI palsy. In all patients with ruptured PICA aneurysms and CN VI palsy, dome projection and presumed direction of rupture were directed toward the ipsilateral and/or contralateral Dorello's canal, in agreement with laterality of the CN palsy. In patients with bilateral CN VI palsies, a medial projection with extensive subarachnoid blood was observed near bilateral canals. CONCLUSIONS This study establishes a localizing connection between an isolated CN VI palsy, SAH, and an underlying ruptured PICA aneurysm. CN VI palsy is an important clinical sign in aSAH and when present on initial clinical presentation may be assumed to be due to ruptured PICA aneurysms until proven otherwise. The deficit may be ipsilateral, contralateral, or bilateral and is determined by the direction of the aneurysm dome projection and extent of subarachnoid bleeding toward Dorello's canal, rather than by direct compression.

Sex differences in aneurysm morphologies and clinical outcomes in ruptured anterior communicating artery aneurysms: a retrospective study

PubMed Central

Lin, Boli; Chen, Weijian; Ruan, Lei; Chen, Yongchun; Zhong, Ming; Zhuge, Qichuan; Fan, Liang Hao; Zhao, Bing; Yang, Yunjun

2016-01-01

Objectives Ruptured anterior communicating artery (ACoA) aneurysms occur more frequently in men. The purpose of the study was to investigate sex difference in aneurysm morphologies and clinical outcomes in patients with ruptured ACoA aneurysms. Setting A tertiary referral hospital. Participants A total of 574 consecutive patients with ACoA aneurysms were admitted to our hospital from December 2007 to February 2015. In all, 474 patients (257 men and 217 women) with ruptured ACoA aneurysms were included in the study. Main outcome measures Aneurysm morphologies were measured using computed tomographic angiography and clinical outcomes were measured with Glasgow coma score at discharge. Results The aneurysm sizes (p=0.001), aneurysm heights (p=0.011), size ratios (p<0.001), flow angles (p=0.047) and vessel angles (p=0.046) were larger in the male patients than in the females. The female patients more often had larger vessel sizes (p=0.002). Multivariate logistic analysis revealed that significant differences in aneurysm morphologies between men and women were aneurysm size (OR 1.1, 95% CI 1.0 to 1.3; p=0.036), aneurysm height (OR 0.8, 95% CI 0. to 0.9; p=0.006) and size ratio (OR 1.4, 95% CI 0.5 to 1.7; p=0.001). There were no statistically significant differences in the outcomes between men and women (OR 1.0, 95% CI 0.6 to 1.7, p=0.857). Conclusions The men were independently associated with larger aneurysm sizes, greater aneurysm heights and larger size ratios. Sex was not a risk factor for poor outcome in patients with ruptured ACoA aneurysms. PMID:27084272

Angiographic analysis of animal model aneurysms treated with novel polyurethane asymmetric vascular stent (P-AVS): feasibility study.

PubMed

Ionita, Ciprian N; Dohatcu, Andreea; Sinelnikov, Andrey; Sherman, Jason; Keleshis, Christos; Paciorek, Ann M; Hoffmann, K R; Bednarek, D R; Rudin, S

2009-01-01

Image-guided endovascular intervention (EIGI), using new flow modifying endovascular devices for intracranial aneurysm treatment is an active area of stroke research. The new polyurethane-asymmetric vascular stent (P-AVS), a vascular stent partially covered with a polyurethane-based patch, is used to cover the aneurysm neck, thus occluding flow into the aneurysm. This study involves angiographic imaging of partially covered aneurysm orifices. This particular situation could occur when the vascular geometry does not allow full aneurysm coverage. Four standard in-vivo rabbit-model aneurysms were investigated; two had stent patches placed over the distal region of the aneurysm orifice while the other two had stent patches placed over the proximal region of the aneurysm orifice. Angiographic analysis was used to evaluate aneurysm blood flow before and immediately after stenting and at four-week follow-up. The treatment results were also evaluated using histology on the aneurysm dome and electron microscopy on the aneurysm neck. Post-stenting angiographic flow analysis revealed aneurysmal flow reduction in all cases with faster flow in the distally-covered case and very slow flow and prolonged pooling for proximal-coverage. At follow-up, proximally-covered aneurysms showed full dome occlusion. The electron microscopy showed a remnant neck in both distally-placed stent cases but complete coverage in the proximally-placed stent cases. Thus, direct flow (impingement jet) removal from the aneurysm dome, as indicated by angiograms in the proximally-covered case, was sufficient to cause full aneurysm healing in four weeks; however, aneurysm healing was not complete for the distally-covered case. These results support further investigations into the treatment of aneurysms by flow-modification using partial aneurysm-orifice coverage.

Angiographic analysis of animal model aneurysms treated with novel polyurethane asymmetric vascular stent (P-AVS): feasibility study

PubMed Central

Ionita, Ciprian N.; Dohatcu, Andreea; Sinelnikov, Andrey; Sherman, Jason; Keleshis, Christos; Paciorek, Ann M.; Hoffmann, K R.; Bednarek, D. R.; Rudin, S

2009-01-01

Image-guided endovascular intervention (EIGI), using new flow modifying endovascular devices for intracranial aneurysm treatment is an active area of stroke research. The new polyurethane-asymmetric vascular stent (P-AVS), a vascular stent partially covered with a polyurethane-based patch, is used to cover the aneurysm neck, thus occluding flow into the aneurysm. This study involves angiographic imaging of partially covered aneurysm orifices. This particular situation could occur when the vascular geometry does not allow full aneurysm coverage. Four standard in-vivo rabbit-model aneurysms were investigated; two had stent patches placed over the distal region of the aneurysm orifice while the other two had stent patches placed over the proximal region of the aneurysm orifice. Angiographic analysis was used to evaluate aneurysm blood flow before and immediately after stenting and at four-week follow-up. The treatment results were also evaluated using histology on the aneurysm dome and electron microscopy on the aneurysm neck. Post-stenting angiographic flow analysis revealed aneurysmal flow reduction in all cases with faster flow in the distally-covered case and very slow flow and prolonged pooling for proximal-coverage. At follow-up, proximally-covered aneurysms showed full dome occlusion. The electron microscopy showed a remnant neck in both distally-placed stent cases but complete coverage in the proximally-placed stent cases. Thus, direct flow (impingement jet) removal from the aneurysm dome, as indicated by angiograms in the proximally-covered case, was sufficient to cause full aneurysm healing in four weeks; however, aneurysm healing was not complete for the distally-covered case. These results support further investigations into the treatment of aneurysms by flow-modification using partial aneurysm-orifice coverage. PMID:19763252

A Thrombus Generation Model Applied to Aneurysms Treated with Shape Memory Polymer Foam and Metal Coils

NASA Astrophysics Data System (ADS)

Horn, John; Ortega, Jason; Hartman, Jonathan; Maitland, Duncan

2015-11-01

To prevent their rupture, intracranial aneurysms are often treated with endovascular metal coils which fill the aneurysm sac and isolate it from the arterial flow. Despite its widespread use, this method can result in suboptimal outcomes leading to aneurysm recurrence. Recently, shape memory polymer foam has been proposed as an alternative aneurysm filler. In this work, a computational model has been developed to predict thrombus formation in blood in response to such cardiovascular implantable devices. The model couples biofluid and biochemical phenomena present as the blood interacts with a device and stimulates thrombus formation. This model is applied to simulations of both metal coil and shape memory polymer foam treatments within an idealized 2D aneurysm geometry. Using the predicted thrombus responses, the performance of these treatments is evaluated and compared. The results suggest that foam-treated aneurysms may fill more quickly and more completely with thrombus than coil-filled aneurysms, potentially leading to improved long-term aneurysm healing. This work was performed in part under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

The effect of endograft device on patient outcomes in endovascular repair of ruptured abdominal aortic aneurysms.

PubMed

Kansal, Vinay; Nagpal, Sudhir; Jetty, Prasad

2017-12-01

Objective Endovascular aneurysm repair for ruptured abdominal aortic aneurysm is being increasingly applied as the intervention of choice. The purpose of this study was to determine whether survival and reintervention rates after ruptured abdominal aortic aneurysm vary between endograft devices. Methods This cohort study identified all ruptured abdominal aortic aneurysms performed at The Ottawa Hospital from January 1999 to May 2015. Data collected included patient demographics, stability index at presentation, adherence to device instructions for use, endoleaks, reinterventions, and mortality. Kruskal-Wallis test was used to compare outcomes between groups. Mortality outcomes were assessed using Kaplan-Meier survival analysis, and multivariate Cox regression modeling. Results One thousand sixty endovascular aneurysm repairs were performed using nine unique devices. Ninety-six ruptured abdominal aortic aneurysms were performed using three devices: Cook Zenith ( n = 46), Medtronic Endurant ( n = 33), and Medtronic Talent ( n = 17). The percent of patients presented in unstable or extremis condition was 30.2, which did not differ between devices. Overall 30-day mortality was 18.8%, and was not statistically different between devices ( p = 0.16), although Medtronic Talent had markedly higher mortality (35.3%) than Cook Zenith (15.2%) and Medtronic Endurant (15.2%). AUI configuration was associated with increased 30-day mortality (33.3% vs. 12.1%, p = 0.02). Long-term mortality and graft-related reintervention rates at 30 days and 5 years were similar between devices. Instructions for use adherence was similar across devices, but differed between the ruptured abdominal aortic aneurysm and elective endovascular aneurysm repair cohorts (47.7% vs. 79.0%, p < 0.01). Notably, two patients who received Medtronic Talent grafts underwent open conversion >30 days post-endovascular aneurysm repair ( p = 0.01). Type 1 endoleak rates differed significantly across devices (Cook Zenith 0.0%, Medtronic Endurant 18.2%, Medtronic Talent 17.6%, p = 0.01). Conclusion Although we identified device-related differences in endoleak rates, there were no significant differences in reintervention rates or mortality outcomes. Favorable outcomes of Cook Zenith and Medtronic Endurant over Medtronic Talent reflect advances in endograft technology and improvements in operator experience over time. Results support selection of endograft by operator preference for ruptured abdominal aortic aneurysm.

Measurement with microscopic MRI and simulation of flow in different aneurysm models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edelhoff, Daniel, E-mail: daniel.edelhoff@tu-dortmund.de; Frank, Frauke; Heil, Marvin

2015-10-15

Purpose: The impact and the development of aneurysms depend to a significant degree on the exchange of liquid between the regular vessel and the pathological extension. A better understanding of this process will lead to improved prediction capabilities. The aim of the current study was to investigate fluid-exchange in aneurysm models of different complexities by combining microscopic magnetic resonance measurements with numerical simulations. In order to evaluate the accuracy and applicability of these methods, the fluid-exchange process between the unaltered vessel lumen and the aneurysm phantoms was analyzed quantitatively using high spatial resolution. Methods: Magnetic resonance flow imaging was usedmore » to visualize fluid-exchange in two different models produced with a 3D printer. One model of an aneurysm was based on histological findings. The flow distribution in the different models was measured on a microscopic scale using time of flight magnetic resonance imaging. The whole experiment was simulated using fast graphics processing unit-based numerical simulations. The obtained simulation results were compared qualitatively and quantitatively with the magnetic resonance imaging measurements, taking into account flow and spin–lattice relaxation. Results: The results of both presented methods compared well for the used aneurysm models and the chosen flow distributions. The results from the fluid-exchange analysis showed comparable characteristics concerning measurement and simulation. Similar symmetry behavior was observed. Based on these results, the amount of fluid-exchange was calculated. Depending on the geometry of the models, 7% to 45% of the liquid was exchanged per second. Conclusions: The result of the numerical simulations coincides well with the experimentally determined velocity field. The rate of fluid-exchange between vessel and aneurysm was well-predicted. Hence, the results obtained by simulation could be validated by the experiment. The observed deviations can be caused by the noise in the measurement and by the limited resolution of the simulation. The resulting differences are small enough to allow reliable predictions of the flow distribution in vessels with stents and for pulsed blood flow.« less

Natural History of Vertebrobasilar Dolichoectatic and Fusiform Aneurysms: A Systematic Review and Meta-Analysis.

PubMed

Nasr, Deena M; Flemming, Kelly D; Lanzino, Giuseppe; Cloft, Harry J; Kallmes, David F; Murad, Mohammad Hassan; Brinjikji, Waleed

2018-01-01

Vertebrobasilar non-saccular and dolichoectatic aneurysms (VBDA) are a rare type of aneurysm and are generally associated with poor prognosis. In order to better characterize the natural history of VBDAs, we performed a systematic review and meta-analysis of the literature to determine rates of mortality, growth, rupture, ischemia, and intraparenchymal hemorrhage. We searched the literature for longitudinal natural history studies of VBDA patients reporting clinical and imaging outcomes. Studied outcomes included annualized rates of growth, rupture, ischemic stroke, intracerebral hemorrhage (ICH), and mortality. We also studied the association between aneurysm morphology (dolichoectatic versus fusiform) and natural history. Meta-analysis was performed using a random-effects model using summary statistics from included studies. Fifteen studies with 827 patients and 5,093 patient-years were included. The overall annual mortality rate among patients with VBDAs was 13%/year (95% CI 8-19). Patients with fusiform aneurysms had a higher mortality rate than those with dolichoectatic aneurysms, but this did not reach statistical significance (12 vs. 8%, p = 0.11). The overall growth rate was 6%/year (95% CI 4-13). Patients with fusiform aneurysms had higher growth rates than those with dolichoectatic aneurysms (12 vs. 3%, p < 0.0001). The overall rupture rate was 3%/year (95% CI 1-5). Patients with fusiform aneurysms had higher rupture rates than those with dolichoectatic aneurysms (3 vs. 0%, p < 0.0001). The overall rate of ischemic stroke was 6%/year (95% CI 4-9). Patients with dolichoectatic aneurysms had higher ischemic stroke rates than those with fusiform aneurysms, but this did not reach statistical significance (8 vs. 4%, p = 0.13). The overall rate of ICH was 2%/year (95% CI 0-8) with no difference in rates between dolichoectatic and fusiform aneurysms (2 vs. 2%, p = 0.65). In general, the natural history of -VBDAs is poor. However, dolichoectatic and fusiform -VBDAs appear to have distinct natural histories with substantially higher growth and rupture associated with fusiform aneurysms. These findings suggest that these aneurysms should be considered separate entities. Further studies on the natural history of vertebrobasilar dolichoectatic and fusiform aneurysms with more complete follow-up are needed to better understand the risk factors for progression of these aneurysms. © 2018 S. Karger AG, Basel.

Current status of endoluminal grafting for exclusion of abdominal aortic aneurysms. The beauty and the beast.

PubMed Central

Diethrich, E B

1998-01-01

The exclusion of abdominal aortic aneurysms with endoluminal grafts has generated a great deal of interest since the early 1990s, and many centers are currently evaluating the procedure and comparing it to classic surgical exclusion. Although endoluminal grafting procedures show promise, development and clinical testing of devices is a time-consuming process that is influenced greatly by the regulatory climate in the country where the clinical trials take place. Nevertheless, a number of devices are currently under study, and the advantages of 2nd- and 3rd-generation technology are reflected in reduced rates of complications such as endoleaks and thrombosis. Further study will be required to perfect these devices and observe their long-term success in the exclusion of abdominal aortic aneurysms. Images PMID:9566057

Current status of endoluminal grafting for exclusion of abdominal aortic aneurysms. The beauty and the beast.

PubMed

Diethrich, E B

1998-01-01

The exclusion of abdominal aortic aneurysms with endoluminal grafts has generated a great deal of interest since the early 1990s, and many centers are currently evaluating the procedure and comparing it to classic surgical exclusion. Although endoluminal grafting procedures show promise, development and clinical testing of devices is a time-consuming process that is influenced greatly by the regulatory climate in the country where the clinical trials take place. Nevertheless, a number of devices are currently under study, and the advantages of 2nd- and 3rd-generation technology are reflected in reduced rates of complications such as endoleaks and thrombosis. Further study will be required to perfect these devices and observe their long-term success in the exclusion of abdominal aortic aneurysms.

Aneurysms with persistent filling after failed treatment with the Pipeline embolization device.

PubMed

Daou, Badih; Atallah, Elias; Chalouhi, Nohra; Starke, Robert M; Oliver, Jeffrey; Montano, Maria; Jabbour, Pascal; Rosenwasser, Robert H; Tjoumakaris, Stavropoula I

2018-05-04

OBJECTIVE The Pipeline embolization device (PED) has become a valuable tool in the treatment of cerebral aneurysms. Although failures with PED treatment have been reported, the characteristics and course of these aneurysms remain a topic of uncertainty. METHODS Electronic medical records and imaging studies were reviewed for all patients treated with the PED between July 2010 and March 2015 to identify characteristics of patients and aneurysms with residual filling after PED treatment. RESULTS Of 316 cases treated at a single institution, 281 patients had a long-term follow-up. A total of 52 (16.4%) aneurysms with residual filling were identified and constituted the study population. The mean patient age in this population was 58.8 years. The mean aneurysm size was 10.1 mm ± 7.15 mm. Twelve aneurysms were fusiform (23%). Of the aneurysms with residual filling, there were 20 carotid ophthalmic (CO) aneurysms (20% of all CO aneurysms treated), 10 other paraclinoid aneurysms (16.4% of all paraclinoid aneurysms), 7 posterior communicating artery (PCoA) aneurysms (21.9% of all PCoA aneurysms), 7 cavernous internal carotid artery (ICA) aneurysms (14.9% of all cavernous ICA aneurysms), 4 vertebrobasilar (VB) junction aneurysms (14.8% of all VB junction aneurysms), and 3 middle cerebral artery (MCA) aneurysms (25% of all MCA aneurysms). Eleven patients underwent placement of more than one PED (21.2%), with a mean number of devices of 1.28 per case. Eight of 12 aneurysms were previously treated with a stent (15.4%). Nineteen patients underwent re-treatment (36.5%); the 33 patients who did not undergo re-treatment (63.5%) were monitored by angiography or noninvasive imaging. In multivariate analysis, age older than 65 years (OR 2.65, 95% CI 1.33-5.28; p = 0.05), prior stent placement across the target aneurysm (OR 2.94, 95% CI 1.15-7.51; p = 0.02), aneurysm location in the distal anterior circulation (MCA, PCoA, and anterior choroidal artery: OR 2.72, 95% CI 1.19-6.18; p = 0.017), and longer follow-up duration (OR 1.06, 95% CI 1.03-1.09; p < 0.001) were associated with incomplete aneurysm occlusion. CONCLUSIONS While the PED can allow for treatment of large, broad-necked aneurysms with high efficacy, treatment failures do occur (16.4%). Aneurysm size, shape, and previous treatment may influence treatment outcome.

Flow diverter effect of LVIS stent on cerebral aneurysm hemodynamics: a comparison with Enterprise stents and the Pipeline device.

PubMed

Wang, Chao; Tian, Zhongbin; Liu, Jian; Jing, Linkai; Paliwal, Nikhil; Wang, Shengzhang; Zhang, Ying; Xiang, Jianping; Siddiqui, Adnan H; Meng, Hui; Yang, Xinjian

2016-07-02

The aim of this study was to quantify the effect of the new Low-profile Visualized Intraluminal Support (LVIS®D) device and the difference of fluid diverting effect compared with the Pipeline device and the Enterprise stent using computational fluid dynamics (CFD). In this research, we simulated three aneurysms constructed from 3D digital subtraction angiography (DSA). The Enterprise, LVIS and the Pipeline device were virtually conformed to fit into the vessel lumen and placed across the aneurysm orifice. Computational fluid dynamics analysis was performed to compare the hemodynamic differences such as WSS, Velocity and Pressure among these stents. Control referred to the unstented model, the percentage of hemodynamic changes were all compared to Control. A single LVIS stent caused more wall shear stress reduction than double Enterprise stents (39.96 vs. 30.51 %) and velocity (23.13 vs. 18.64 %). Significant reduction in wall shear stress (63.88 %) and velocity (46.05 %) was observed in the double-LVIS stents. A single Pipeline showed less reduction in WSS (51.08 %) and velocity (37.87 %) compared with double-LVIS stent. The double-Pipeline stents resulted in the most reduction in WSS (72.37 %) and velocity (54.26 %). Moreover, the pressure increased with minuscule extent after stenting, compared with the unstented model. This is the first study analyzing flow modifications associated with LVIS stents. We found that the LVIS stent has certain hemodynamic effects on cerebral aneurysms: a single LVIS stent caused more flow reductions than the double-Enterprise stent but less than a Pipeline device. Nevertheless, the double-LVIS stent resulted in a better flow diverting effect than a Pipeline device.

Comparison of 3D computer-aided with manual cerebral aneurysm measurements in different imaging modalities.

PubMed

Groth, M; Forkert, N D; Buhk, J H; Schoenfeld, M; Goebell, E; Fiehler, J

2013-02-01

To compare intra- and inter-observer reliability of aneurysm measurements obtained by a 3D computer-aided technique with standard manual aneurysm measurements in different imaging modalities. A total of 21 patients with 29 cerebral aneurysms were studied. All patients underwent digital subtraction angiography (DSA), contrast-enhanced (CE-MRA) and time-of-flight magnetic resonance angiography (TOF-MRA). Aneurysm neck and depth diameters were manually measured by two observers in each modality. Additionally, semi-automatic computer-aided diameter measurements were performed using 3D vessel surface models derived from CE- (CE-com) and TOF-MRA (TOF-com) datasets. Bland-Altman analysis (BA) and intra-class correlation coefficient (ICC) were used to evaluate intra- and inter-observer agreement. BA revealed the narrowest relative limits of intra- and inter-observer agreement for aneurysm neck and depth diameters obtained by TOF-com (ranging between ±5.3 % and ±28.3 %) and CE-com (ranging between ±23.3 % and ±38.1 %). Direct measurements in DSA, TOF-MRA and CE-MRA showed considerably wider limits of agreement. The highest ICCs were observed for TOF-com and CE-com (ICC values, 0.92 or higher for intra- as well as inter-observer reliability). Computer-aided aneurysm measurement in 3D offers improved intra- and inter-observer reliability and a reproducible parameter extraction, which may be used in clinical routine and as objective surrogate end-points in clinical trials.

Endovascular minimally invasive treatment of the intracranial aneurysms--first 124 cases.

PubMed

Dima, S; Scheau, C; Stefanescu, F; Danaila, L

2012-09-15

Since May 2005, we have started to treat the intracranial aneurysms endovascular way as an alternative minimally invasive technique to the classic neurosurgery treatment. Studying the patients' demographics, clinical presentation, aneurysm size and configuration, type of coils used for embolization, the percentage of compaction and recanalization (especially in patients who presented with subarachnoid hemorrhage), and immediate complications. An all-inclusive retrospective review of every patient who underwent coils embolization (stent or balloon assisted included) of saccular aneurysms from May 2005 to September 2011 was performed. A total of 116 patients (46 men and 60 women) and 124 aneurysms were treated. A total of 96 patients (41 men and 55 women) underwent follow-up femoral cerebral angiograms (mean follow-up was 25 months and the longest was at 37 months). Five patients required intra-arterial abciximab due to thrombus formation. Four patients had aneurysm rupture while the coil was being advanced. Eleven patients were treated during vasospasm peak. Seven patients had recanalization at 12 months follow-up. The average hospitalization period was of 4 days. There is a close relation between Hunt and Hess scale score before treatment and post interventional neurological status. Due to subarachnoid hemorrhage, the vasospasm remains a threat to the patient's neurological status. The treatment of cerebral aneurysms with endosacular embolization by coils is a safe and durable option. The risk of recanalization or re-rupture in our cohort is small compared to series published elsewhere. Larger series of patients are needed to support our evidence.

Resolution of Oculomotor Nerve Palsy Secondary to Posterior Communicating Artery Aneurysms: Comparison of Clipping and Coiling.

PubMed

McCracken, D Jay; Lovasik, Brendan P; McCracken, Courtney E; Caplan, Justin M; Turan, Nefize; Nogueira, Raul G; Cawley, C Michael; Dion, Jacques E; Tamargo, Rafael J; Barrow, Daniel L; Pradilla, Gustavo

2015-12-01

Previous studies have attempted to determine the best treatment for oculomotor nerve palsy (ONP) secondary to posterior communicating artery (PCoA) aneurysms, but have been limited by small sample sizes and limited treatment. To analyze the treatment of ONP secondary to PCoA with both coiling and clipping in ruptured and unruptured aneurysms. Data from 2 large academic centers was retrospectively collected over 22 years, yielding a total of 93 patients with ONP secondary to PCoA aneurysms. These patients were combined with 321 patients from the literature review for large data analyses. Onset symptoms, recovery, and time to resolution were evaluated with respect to treatment and aneurysm rupture status. For all patients presenting with ONP (n = 414) 56.6% of those treated with microsurgical clipping made a full recovery vs 41.5% of those treated with endovascular coil embolization (P = .02). Of patients with a complete ONP (n = 229), full recovery occurred in 47.3% of those treated with clipping but in only 20% of those undergoing coiling (P = .01). For patients presenting with ruptured aneurysms (n = 130), full recovery occurred in 70.9% compared with 49.3% coiled patients (P = .01). Additionally, although patients with full ONP recovery had a median time to treatment of 4 days, those without full ONP recovery had a median time to treatment of 7 days (P = .01). Patients with ONP secondary to PCoA aneurysms treated with clipping showed higher rates of full ONP resolution than patients treated with coil embolization. Larger prospective studies are needed to determine the true potential of recovery associated with each treatment. EUH, Emory University HospitalIQR, interquartile rangeJHU, Johns Hopkins UniversitymRS, modified Rankin ScaleONP, oculomotor nerve palsyPCoA, posterior communicating arterySAH, subarachnoid hemorrhage.

Flow Diversion versus Standard Endovascular Techniques for the Treatment of Unruptured Carotid-Ophthalmic Aneurysms.

PubMed

Di Maria, F; Pistocchi, S; Clarençon, F; Bartolini, B; Blanc, R; Biondi, A; Redjem, H; Chiras, J; Sourour, N; Piotin, M

2015-12-01

Over the past few years, flow diversion has been increasingly adopted for the treatment of intracranial aneurysms, especially in the paraclinoid and paraophthalmic carotid segment. We compared clinical and angiographic outcomes and complication rates in 2 groups of patients with unruptured carotid-ophthalmic aneurysms treated for 7 years by either standard coil-based techniques or flow diversion. From February 2006 to December 2013, 162 unruptured carotid-ophthalmic aneurysms were treated endovascularly in 138 patients. Sixty-seven aneurysms were treated by coil-based techniques in 61 patients. Flow diverters were deployed in 95 unruptured aneurysms (77 patients), with additional coiling in 27 patients. Complication rates, clinical outcome, and immediate and long-term angiographic results were retrospectively analyzed. No procedure-related deaths occurred. Four procedure-related thromboembolic events (6.6%) leading to permanent morbidity in 1 case (1.6%) occurred in the coiling group. Neurologic complications were observed in 6 patients (7.8%) in the flow-diversion group, resulting in 3.9% permanent morbidity. No statistically significant difference was found between complication (P = .9) and morbidity rates (P = .6). In the coiling group (median follow-up, 31.5 ± 24.5 months), recanalization occurred at 1 year in 23/50 (54%) aneurysms and 27/55 aneurysms (50.9%) at the latest follow-up, leading to retreatment in 6 patients (9%). In the flow-diversion group (mean follow-up, 13.5 ± 10.8 months), 85.3% (35/41) of all aneurysms were occluded after 12 months, and 74.6% (50/67) on latest follow-up. The retreatment rate was 2.1%. Occlusion rates between the 2 groups differed significantly at 12 months (P < .001) and at the latest follow-up (P < .005). Our retrospective analysis shows better long-term occlusion of carotid-ophthalmic aneurysms after use of flow diverters compared with standard coil-based techniques, without significant differences in permanent morbidity. © 2015 by American Journal of Neuroradiology.

Aneurysm flow characteristics in realistic carotid artery aneurysm models induced by proximal virtual stenotic plaques: a computational hemodynamics study

NASA Astrophysics Data System (ADS)

Castro, Marcelo A.; Peloc, Nora L.; Chien, Aichi; Goldberg, Ezequiel; Putman, Christopher M.; Cebral, Juan R.

2015-03-01

Cerebral aneurysms may rarely coexist with a proximal artery stenosis. In that small percent of patients, such coexistence poses a challenge for interventional neuroradiologists and neurosurgeons to make the best treatment decision. According to previous studies, the incidence of cerebral aneurysms in patients with internal carotid artery stenosis is no greater than five percent, where the aneurysm is usually incidentally detected, being about two percent for aneurysms and stenoses in the same cerebral circulation. Those cases pose a difficult management decision for the physician. Case reports showed patients who died due to aneurysm rupture months after endarterectomy but before aneurysm clipping, while others did not show any change in the aneurysm after plaque removal, having optimum outcome after aneurysm coiling. The aim of this study is to investigate the intra-aneurysmal hemodynamic changes before and after treatment of stenotic plaque. Virtually created moderate stenoses in vascular models of internal carotid artery aneurysm patients were considered in a number of cases reconstructed from three dimensional rotational angiography images. The strategy to create those plaques was based on parameters analyzed in a previous work where idealized models were considered, including relative distance and stenosis grade. Ipsilateral and contralateral plaques were modeled. Wall shear stress and velocity pattern were computed from finite element pulsatile blood flow simulations. The results may suggest that wall shear stress changes depend on relative angular position between the aneurysm and the plaque.

Fluid, solid and fluid-structure interaction simulations on patient-based abdominal aortic aneurysm models.

PubMed

Kelly, Sinead; O'Rourke, Malachy

2012-04-01

This article describes the use of fluid, solid and fluid-structure interaction simulations on three patient-based abdominal aortic aneurysm geometries. All simulations were carried out using OpenFOAM, which uses the finite volume method to solve both fluid and solid equations. Initially a fluid-only simulation was carried out on a single patient-based geometry and results from this simulation were compared with experimental results. There was good qualitative and quantitative agreement between the experimental and numerical results, suggesting that OpenFOAM is capable of predicting the main features of unsteady flow through a complex patient-based abdominal aortic aneurysm geometry. The intraluminal thrombus and arterial wall were then included, and solid stress and fluid-structure interaction simulations were performed on this, and two other patient-based abdominal aortic aneurysm geometries. It was found that the solid stress simulations resulted in an under-estimation of the maximum stress by up to 5.9% when compared with the fluid-structure interaction simulations. In the fluid-structure interaction simulations, flow induced pressure within the aneurysm was found to be up to 4.8% higher than the value of peak systolic pressure imposed in the solid stress simulations, which is likely to be the cause of the variation in the stress results. In comparing the results from the initial fluid-only simulation with results from the fluid-structure interaction simulation on the same patient, it was found that wall shear stress values varied by up to 35% between the two simulation methods. It was concluded that solid stress simulations are adequate to predict the maximum stress in an aneurysm wall, while fluid-structure interaction simulations should be performed if accurate prediction of the fluid wall shear stress is necessary. Therefore, the decision to perform fluid-structure interaction simulations should be based on the particular variables of interest in a given study.

Male gender and smoking are related to single, but not to multiple, human aortic aneurysms.

PubMed

Gutierrez, Paulo S; Leite, Thiago N P; Mangione, Fernanda M

2015-01-01

There is scanty information concerning multiple aortic aneurysms. Thus, we verified if clinical or pathological characteristics are different in patients with multiple (two or more) aortic aneurysms in comparison with those with only one. We selected at the necropsy files of the Heart Institute, São Paulo University School of Medicine, the last 100 cases with aortic aneurysms, comparing between the two groups: sex, age, presence of systemic arterial hypertension, diabetes, dyslipedemia, history of smoking habit, cause of the aneurysm, cause of death, and if the diagnosis was reached during life. Age was analysed by Mann-Whitney test, and the other variables by chi-square or Fisher's exact test. Multiple aneurysms corresponded to 14% of cases. The proportion of women among patients with multiple aneurysms was higher than among those with single aneurysm (64.3% versus 20.9%, P<.01), even if only cases with atherosclerosis were taken into consideration (women among multiple-6/10, 60.0%; among single-14/70, 20.0%; P=.01). Smoking was less reported in cases with multiple (4/14, 28.6%) than with single aneurysm (53/86, 61.6%; P=.04); considering cases with atherosclerosis, such difference decreases (40.0% of multiple versus 68.6% of single, P=.09). although atherosclerosis is present in most cases of both single and multiple aortic aneurysms, male gender and smoking, considered highly influential in such lesions, are less frequent in patients with multiple than in patients with single aneurysms. Thus mechanisms underlying multiple aortic aneurysms are probably different from those related to single, more common aneurysms. Copyright © 2015 Elsevier Inc. All rights reserved.

Preoperative Prediction of the Necessity for Anterior Clinoidectomy During Microsurgical Clipping of Ruptured Posterior Communicating Artery Aneurysms.

PubMed

Kamide, Tomoya; Burkhardt, Jan-Karl; Tabani, Halima; Safaee, Michael M; Lawton, Michael T

2018-01-01

Although most posterior communicating artery (PCoA) aneurysms can be clipped easily with excellent results, some require anterior clinoidectomy for safe and complete clipping. To review our microsurgical series of ruptured PCoA aneurysms and identify the preoperative predictors for anterior clinoidectomy during microsurgical clipping for PCoA aneurysms. Results from microsurgical clipping of 104 patients with ruptured PCoA aneurysms were reviewed retrospectively. Distances and angles were obtained from computed tomographic angiography and compared between the anterior and nonanterior clinoidectomy groups. Anterior clinoidectomy was required in 19 of the 104 cases (18%). None developed surgical complications due to anterior clinoid process (ACP) resection, including postoperative visual deficit. Univariate and multivariate analyses revealed that the distances from the ACP tip to the aneurysmal proximal neck and from the ACP line to the aneurysmal proximal neck were statistically significant predictive factors for the need of anterior clinoidectomy. Based on a receiver operating characteristic analysis, the distances from the ACP tip to the aneurysmal proximal neck <4.0 mm and from the ACP line to the aneurysmal proximal neck ≤2.0 mm were selected as optimal cutoff values for predicting the necessity of anterior clinoidectomy, and the area under the receiver operating characteristic curve values were 0.991 and 0.955, respectively. In case of ruptured PCoA aneurysm surgery, the distances from the ACP tip to the aneurysmal proximal neck and from the ACP line to the aneurysmal proximal neck were both found to be useful predictors of whether anterior clinoidectomy was required. Copyright © 2017 Elsevier Inc. All rights reserved.

Results of open pararenal abdominal aortic aneurysm repair: single centre series and pooled analysis of literature.

PubMed

van Lammeren, Guus W; Ünlü, Çağdaş; Verschoor, Sjoerd; van Dongen, Eric P; Wille, Jan; van de Pavoordt, Eric Dwm; de Vries-Werson, Debbie Ab; De Vries, Jean-Paul Pm

2017-06-01

Objectives Endovascular treatment of pararenal abdominal aortic aneurysm has gained terrain over the past decade, despite the substantial need for reinterventions during follow-up. However, open repair is still a well-established treatment option. With the current study we report the results of a consecutive series of elective primary open pararenal abdominal aortic aneurysm repair in a tertiary vascular referral centre, combined with an overview of current literature and pooled data analysis of perioperative mortality of open and endovascular pararenal abdominal aortic aneurysm repair. Methods A retrospective analysis of a prospective database of all elective open pararenal abdominal aortic aneurysm repairs in the St. Antonius Hospital between 2005 and 2014 was performed. Primary endpoint was 30-day mortality. Secondary endpoints were 30-day morbidity, new onset dialysis, reintervention free survival, and overall survival during follow-up. Results Between 2005 and 2014, 214 consecutive patients underwent elective open pararenal abdominal aortic aneurysm repair. Mean age was 69.8 (±7.1) years, 82.7% (177/214) were men, and mean abdominal aortic aneurysm diameter was 62 (±11) mm. Thirty-day mortality was 3.4%. Thirty-day morbidity was 27.1%, which predominantly consisted of pneumonia (18.7% (40/214)), cardiac events (3.3% (7/214)), and new onset dialysis (2.8% (6/214)). Estimated five-year overall survival rate was 74.2%. 0.9% (2/214) of patients required abdominal aortic aneurysm-related reintervention, and an additional 2.3% (5/214) required surgical repair of an incisional hernia. Pooled analysis of literature revealed a 30-day mortality of 3.0% for open pararenal repair and 1.9% for fenestrated endovascular repair. Conclusion Open pararenal abdominal aortic aneurysm repair in the era of increasing endovascular options results in acceptable perioperative morbidity and mortality rates. Mid-term reintervention rate is low compared to fenestrated endovascular aneurysm repair. Expertise with open repair still remains essential for treatment of pararenal abdominal aortic aneurysms in the near future, especially for those patients that are declined for endovascular treatment.

Vortex Imprints at the Wall, But Not in the Bulk, Distinguish Ruptured from Unruptured Intracranial Aneurysms

NASA Astrophysics Data System (ADS)

Varble, Nicole; Meng, Hui

2015-11-01

Intracranial aneurysms affect 3% of the population. Risk stratification of aneurysms is important, as rupture often leads to death or permanent disability. Image-based CFD analyses of patient-specific aneurysms have identified low and oscillatory wall shear stress to predict rupture. These stresses are sensed biologically at the luminal wall, but the flow dynamics related to aneurysm rupture requires further understanding. We have conducted two studies: one examines vortex dynamics, and the other, high frequency flow fluctuations in patient-specific aneurysms. In the first study, based on Q-criterion vortex identification, we developed two measures to quantify regions within the aneurysm where rotational flow is dominate: the ratio of volume or surface area where Q >0 vs. the total aneurysmal volume or surface area, respectively termed volume vortex fraction (VVF) and surface vortex fraction (SVF). Statistical analysis of 204 aneurysms shows that SVF, but not VVF, distinguishes ruptured from unruptured aneurysms, suggesting that once again, the local flow patterns on the wall is directly relevant to rupture. In the second study, high-resolution CFD (high spatial and temporal resolutions and second-order discretization schemes) on 56 middle cerebral artery aneurysms shows the presence of temporal fluctuations in 8 aneurysms, but such flow instability bears no correlation with rupture. Support for this work was partially provided by NIH grant (R01 NS091075-01) and a grant from Toshiba Medical Systems Corp.

Complex bilobular, bisaccular, and broad-neck microsurgical aneurysm formation in the rabbit bifurcation model for the study of upcoming endovascular techniques.

PubMed

Marbacher, S; Erhardt, S; Schläppi, J-A; Coluccia, D; Remonda, L; Fandino, J; Sherif, C

2011-04-01

Despite rapid advances in the development of materials and techniques for endovascular intracranial aneurysm treatment, occlusion of large broad-neck aneurysms remains a challenge. Animal models featuring complex aneurysm architecture are needed to test endovascular innovations and train interventionalists. Eleven adult female New Zealand rabbits were assigned to 3 experimental groups. Complex bilobular, bisaccular, and broad-neck venous pouch aneurysms were surgically formed at an artificially created bifurcation of both CCAs. Three and 5 weeks postoperatively, the rabbits underwent 2D-DSA and CE-3D-MRA, respectively. Mortality was 0%. We observed no neurologic, respiratory, or gastrointestinal complications. The aneurysm patency rate was 91% (1 aneurysm thrombosis). There was 1 postoperative aneurysm hemorrhage (9% morbidity). The mean aneurysm volumes were 176.9 ± 63.6 mm(3), 298.6 ± 75.2 mm(3), and 183.4 ± 72.4 mm(3) in bilobular, bisaccular, and broad-neck aneurysms, respectively. The mean operation time was 245 minutes (range, 175-290 minutes). An average of 27 ± 4 interrupted sutures (range, 21-32) were needed to create the aneurysms. This study demonstrates the feasibility of creating complex venous pouch bifurcation aneurysms in the rabbit with low morbidity, mortality, and high short-term aneurysm patency. The necks, domes, and volumes of the bilobular, bisaccular, and broad-neck aneurysms created are larger than those previously described. These new complex aneurysm formations are a promising tool for in vivo animal testing of new endovascular devices.

Assessment of failure to rescue after abdominal aortic aneurysm repair using the National Surgical Quality Improvement Program procedure-targeted data set.

PubMed

Dakour-Aridi, Hanaa; Paracha, Nawar Z; Locham, Satinderjit; Nejim, Besma; Malas, Mahmoud B

2018-05-18

Open aortic repair (OAR) is associated with higher risk of mortality compared with endovascular aneurysm repair (EVAR). The aim of this study was to compare failure to rescue (FTR) after major predischarge complications in patients undergoing OAR and EVAR. Patients who underwent OAR or EVAR in the American College of Surgeons National Surgical Quality Improvement Program between 2011 and 2015 were selected. Patients with ruptured aneurysm and those with type IV thoracoabdominal aneurysms were excluded. The primary outcome was FTR, defined as 30-day mortality in patients who developed at least one complication during their hospital stay. Univariable and multivariable statistics were used. A total of 9097 patients underwent abdominal aortic aneurysm repair. Of those, 3291 (36.2%) had at least one major predischarge complication, 82.5% after OAR (95% confidence interval [CI], 80.9%-84.1%) vs 21.3% after EVAR (95% CI, 20.4%-22.3%; P < .001). Increased FTR was seen after aneurysm rupture, cardiac arrest, septic shock, and acute kidney injury. On multivariable analysis, FTR was not significantly different between OAR and EVAR (adjusted odds ratio, 0.87; 95% CI, 0.61-1.24; P = .44). Propensity score matching and coarsened exact matching showed similar results. Although EVAR has fewer complications and lower in-hospital mortality than OAR, FTR after major predischarge complications does not depend on the type of surgical approach. When an in-hospital major complication occurs after EVAR, surgeons should be alert that FTR risk resulting in mortality is similar to that of OAR. Therefore, there is no safety net with EVAR. Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Women undergoing aortic surgery are at higher risk for unplanned readmissions compared with men especially when discharged home.

PubMed

Flink, Benjamin J; Long, Chandler A; Duwayri, Yazan; Brewster, Luke P; Veeraswamy, Ravi; Gallagher, Katherine; Arya, Shipra

2016-06-01

Women undergoing vascular surgery have higher morbidity and mortality. Our study explores gender-based differences in patient-centered outcomes such as readmission, length of stay (LOS), and discharge destination (home vs nonhome facility) in aortic aneurysm surgery. Patients were identified from the American College of Surgeons National Surgical Quality Improvement Project database (2011-2013) undergoing abdominal, thoracic, and thoracoabdominal aortic aneurysms (N = 17,763), who were discharged and survived their index hospitalization. The primary outcome was unplanned readmission, and secondary outcomes were discharge to a nonhome facility, LOS, and reasons for unplanned readmission. Univariate, multivariate, and stratified analyses based on gender and discharge destination were used. Overall, 1541 patients (8.7%) experienced an unplanned readmission, with a significantly higher risk in women vs men (10.8% vs 8%; P < .001) overall (Procedure subtypes: abdominal aortic aneurysm [10.1% vs 7.7%; P < .001], thoracic aortic aneurysm [14.1% vs 13.5%; P = .8], and thoracoabdominal aortic aneurysm [14.8% vs 10%; P = .051]). The higher odds of readmission in women compared with men persisted in multivariate analysis after controlling for covariates (odds ratio [OR], 1.21; 95% confidence interval [CI], 1.05-1.4). Similarly, the rate of discharge to a nonhome facility was nearly double in women compared with men (20.6% vs 10.7%; P < .001), but discharge to a nonhome facility was not a significant predictor of unplanned readmission. Upon stratification by discharge destination, the higher odds of readmissions in women compared with men occurred in patients who were discharged home (OR, 1.2; 95% CI, 1.02-1.4) but not in those who were discharged to a nonhome facility (OR, 1.06; 95% CI, 0.8-1.4). Significant differences in LOS were seen in patients who were discharged home. No gender differences were found in reasons for readmission with the three most common reasons being thromboembolic events, wound infections, and pneumonia. Gender disparity exists in the risk of unplanned readmission among aortic aneurysm surgery patients. Women who were discharged home have a higher likelihood of unplanned readmission despite longer LOS than men. These data suggest that further study into the discharge planning processes, social factors, and use of rehabilitation services is needed for women undergoing aortic procedures to decrease readmissions. Published by Elsevier Inc.

Wide-neck bifurcation aneurysms of the middle cerebral artery and basilar apex treated by endovascular techniques: a multicentre, core lab adjudicated study evaluating safety and durability of occlusion (BRANCH).

PubMed

De Leacy, Reade A; Fargen, Kyle M; Mascitelli, Justin R; Fifi, Johanna; Turkheimer, Lena; Zhang, Xiangnan; Patel, Aman B; Koch, Matthew J; Pandey, Aditya S; Wilkinson, D Andrew; Griauzde, Julius; James, Robert F; Fortuny, Enzo M; Cruz, Aurora; Boulos, Alan; Nourollah-Zadeh, Emad; Paul, Alexandra; Sauvageau, Eric; Hanel, Ricardo; Aguilar-Salinas, Pedro; Novakovic, Roberta L; Welch, Babu G; Almardawi, Ranyah; Jindal, Gaurav; Shownkeen, Harish; Levy, Elad I; Siddiqui, Adnan H; Mocco, J

2018-06-01

BRANCH (wide-neck bifurcation aneurysms of the middle cerebral artery and basilar apex treated by endovascular techniques) is a multicentre, retrospective study comparing core lab evaluation of angiographic outcomes with self-reported outcomes. Consecutive patients were enrolled from 10 US centres, aged between 18 and 85 with unruptured wide-neck middle cerebral artery (MCA) or basilar apex aneurysms treated endovascularly. Patient demographics, aneurysm morphology, procedural information, mortality and morbidity data and core lab and self-reported modified Raymond Roy (RR) outcomes were obtained. 115 patients met inclusion criteria. Intervention-related mortality and significant morbidity rates were 1.7% (2/115) and 5.8% (6/103) respectively. Core lab adjudicated RR1 and 2 occlusion rates at follow-up were 30.6% and 32.4% respectively. The retreatment rate within the follow-up window was 10/115 (8.7%) and in stent stenosis at follow-up was 5/63 (7.9%). Self-reporting shows a statistically significant direction to angiographic RR one outcomes at follow-up compared with core lab evaluation, with OR 1.75 (95% CI 1.08 to 2.83). Endovascular treatment of wide-neck MCA and basilar apex aneurysms resulted in a core lab adjudicated RR1 occlusion rate of 30.6%. Self-reported results at follow-up favour better angiographic outcomes, with OR 1.75 (95% CI 1.08 to 2.83). These data demonstrate the need for novel endovascular devices specifically designed to treat complex intracranial aneurysms, as well as the importance of core lab adjudication in assessing outcomes in such a trial. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Long-term outcomes after repair of symptomatic abdominal aortic aneurysms.

PubMed

Chandra, Venita; Trang, Karen; Virgin-Downey, Whitt; Dalman, Ronald L; Mell, Matthew W

2018-04-25

Previous studies have reported increased perioperative mortality of nonruptured symptomatic abdominal aortic aneurysms (Sx-AAA) compared with asymptomatic elective AAA (E-AAA) repairs, but no long-term-outcomes have been reported. We sought to compare long-term outcomes of Sx-AAA and E-AAA after repair at a single academic institution. Patients receiving AAA repair for Sx-AAA and E-AAA from 1995 through 2015 were included. Ruptured AAA and suprarenal or thoracoabdominal AAA were excluded. Demographics, comorbidities, and operative approach were collected. Long-term mortality was the primary outcome, determined by chart review or link to Social Security Death Index. Additionally, long-term mortality and reinterventions were compared after groups were matched with nearest neighbor propensity to reduce bias. AAA repair was performed for 1054 E-AAA (383 open repair [36%], 671 endovascular aneurysm repair [EVAR] [64%]), and 139 symptomatic aneurysms (60 open repair [43%], 79 EVAR [57%]). Age (73 years vs 74 years; P = .13) and aneurysm diameter were similar between Sx-AAA and E-AAA (6.0 cm vs 5.8 cm; P = .5). The proportion of women was higher for Sx-AAA (26% vs 16%; P = .003), as was the proportion of non-Caucasians (40% vs 29%; P = .009). After propensity matching, there were no differences between groups for patient characteristics, AAA diameter, treatment modality, or comorbidities, including hypertension, coronary artery disease, congestive heart failure, diabetes, hyperlipidemia, lung disease, diabetes, renal disease, and smoking history. Women were treated for Sx-AAA at significantly smaller aortic diameters; however, compared with men (5.1 cm vs 6.3 cm; P < .001). Perioperative mortality was 5.0% for Sx-AAA and 2.3% for E-AAA (P = .055). By life-table analysis, Sx-AAA had lower 5-year (62% vs 71%) and 10-year (39% vs 51%) survivals (P = .01) compared with E-AAA for the entire cohort. Similar trends were observed for 5-year and 10-year mortality after propensity matching (63% and 40% vs 71% and 52%; P = .05). When stratified by repair type 5-year and 10-year survivals trended lower after open surgery (68% and 42% Sx-AAA vs 84% and 59% E-AAA; P = .08) but not EVAR (59% and 40% Sx-AAA vs 61% and 49% E-AAA; P = .4). Aneurysm-related reinterventions were similar for Sx-AAA and E-AAA (15% vs 14%; P = .8). Reinterventions were more common after EVAR compared with open repair (22% vs 7%, Sx-AAA P = .015; 20% vs 4% E-AAA; P = .007). Patients with Sx-AAA had lower long-term survival and similar aneurysm-related reinterventions compared with patients with E-AAA undergoing repair. Women also underwent repair for Sx-AAA at a significantly smaller size when compared with men, which emphasizes the role of gender in AAA symptomatology. Differences in long-term survival may be only partially explained by measured patient, aneurysm, and operative factors, and may reflect unmeasured social factors or suggest inherent differences in pathophysiology of Sx-AAAs. Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Oculomotor nerve palsy by posterior communicating artery aneurysms: influence of surgical strategy on recovery.

PubMed

Güresir, Erdem; Schuss, Patrick; Seifert, Volker; Vatter, Hartmut

2012-11-01

Resolution of oculomotor nerve palsy (ONP) after clipping of posterior communicating artery (PCoA) aneurysms has been well documented. However, whether additional decompression of the oculomotor nerve via aneurysm sac dissection or resection is superior to pure aneurysm clipping is the subject of much debate. Therefore, the objective in the present investigation was to analyze the influence of surgical strategy--specifically, clipping with or without aneurysm dissection--on ONP resolution. Between June 1999 and December 2010, 18 consecutive patients with ruptured and unruptured PCoA aneurysms causing ONP were treated at the authors' institution. Oculomotor nerve palsy was evaluated on admission and at follow-up. The electronic database MEDLINE was searched for additional data in published studies of PCoA aneurysms causing ONP. Two reviewers independently extracted data. Overall, 8 studies from the literature review and 6 patients in the current series (121 PCoA aneurysms) met the study inclusion criteria. Ninety-four aneurysms were treated with simple aneurysm neck clipping and 27 with clipping plus aneurysm sac decompression. The surgical strategy, simple aneurysm neck clipping versus clipping plus oculomotor nerve decompression, had no effect on full ONP resolution on univariate (p = 0.5) and multivariate analyses. On multivariate analysis, patients with incomplete ONP at admission were more likely to have full resolution of the palsy than were those with complete ONP at admission (p = 0.03, OR = 4.2, 95% CI 1.1-16). Data in the present study indicated that ONP caused by PCoA aneurysms improves after clipping without and with oculomotor nerve decompression. The resolution of ONP is inversely associated with the initial severity of ONP.

Alcohol Consumption and Aneurysmal Subarachnoid Hemorrhage.

PubMed

Can, Anil; Castro, Victor M; Ozdemir, Yildirim H; Dagen, Sarajune; Dligach, Dmitriy; Finan, Sean; Yu, Sheng; Gainer, Vivian; Shadick, Nancy A; Savova, Guergana; Murphy, Shawn; Cai, Tianxi; Weiss, Scott T; Du, Rose

2018-02-01

Alcohol consumption may be a modifiable risk factor for rupture of intracranial aneurysms. Our aim is to evaluate the association between ruptured aneurysms and alcohol consumption, intensity, and cessation. The medical records of 4701 patients with 6411 radiographically confirmed intracranial aneurysms diagnosed at the Brigham and Women's Hospital and Massachusetts General Hospital between 1990 and 2016 were reviewed. Individuals were divided into cases with ruptured aneurysms and controls with unruptured aneurysms. Univariable and multivariable logistic regression analyses were performed to determine the association between alcohol consumption and rupture of intracranial aneurysms. In multivariable analysis, current alcohol use (OR 1.36, 95% CI 1.17-1.58) was associated with rupture status compared with never drinkers, whereas former alcohol use was not significant (OR 1.23, 95% CI 0.92-1.63). In addition, the number of alcoholic beverages per day among current alcohol users (OR 1.13, 95% CI 1.04-1.23) was significantly associated with rupture status, whereas alcohol use intensity was not significant among former users (OR 1.02, 95% CI 0.94-1.11). Current alcohol use and intensity are significantly associated with intracranial aneurysm rupture. However, this increased risk does not persist in former alcohol users, emphasizing the potential importance of alcohol cessation in patients harboring unruptured aneurysms.

Comparison of eye-lens doses imparted during interventional and non-interventional neuroimaging techniques for assessment of intracranial aneurysms.

PubMed

Guberina, N; Dietrich, U; Forsting, M; Ringelstein, A

2018-02-01

A neurointerventional examination of intracranial aneurysms often involves the eye lens in the primary beam of radiation. To assess and compare eye-lens doses imparted during interventional and non-interventional imaging techniques for the examination of intracranial aneurysms. We performed a phantom study on an anthropomorphic phantom (ATOM dosimetry phantom 702-D; CIRS, Norfolk, Virginia, USA) and assessed eye-lens doses with thermoluminescent dosimeters (TLDs) type 100 (LiF:Mg, Ti) during (1) interventional (depiction of all cerebral arteries with triple 3D-rotational angiography and twice 2-plane DSA anteroposterior and lateral projections) and (2) non-interventional (CT angiography (CTA)) diagnosis of intracranial aneurysms. Eye-lens doses were calculated following recommendations of the ICRP 103. Image quality was analysed in retrospective by two experienced radiologists on the basis of non-interventional and interventional pan-angiography examinations of patients with incidental aneurysms (n=50) on a five-point Likert scale. The following eye-lens doses were assessed: (1) interventional setting (triple 3D-rotational angiography and twice 2-plane DSA anteroposterior and lateral projections) 12 mGy; (2) non-interventional setting (CTA) 4.1 mGy. Image quality for depiction of intracranial aneurysms (>3 mm) was evaluated as good by both readers for both imaging techniques. Eye-lens doses are markedly higher during the interventional than during the non-interventional diagnosis of intracranial aneurysms. For the eye-lens dose, CTA offers considerable radiation dose savings in the diagnosis of intracranial aneurysms. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Endovascular image-guided treatment of in-vivo model aneurysms with asymmetric vascular stents (AVS): evaluation with time-density curve angiographic analysis and histology.

PubMed

Dohatcu, A; Ionita, C N; Paciorek, A; Bednarek, D R; Hoffmann, K R; Rudin, S

2008-01-01

In this study, we compare the results obtained from Time-Density Curve (TDC) analysis of angiographic imaging sequences with histological evaluation for a rabbit aneurysm model treated with standard stents and new asymmetric vascular stents (AVS) placed by image-guided endovascular deployment. AVSs are stents having a low-porosity patch region designed to cover the aneurysm neck and occlude blood flow inside. To evaluate the AVSs, rabbits with elastase-induced aneurysm models (n=20) were divided into three groups: the first (n=10) was treated with an AVS, the second (n=5) with a non-patch standard coronary stent, and third was untreated as a control (n=5). We used TDC analysis to measure how much contrast media entered the aneurysm before and after treatment. TDCs track contrast-media-density changes as a function of time over the region of interest in x-ray DSA cine-sequences. After 28 days, the animals were sacrificed and the explanted specimens were histologically evaluated. The first group showed an average reduction of contrast flow into the aneurysm of 95% after treatment with an AVS with fully developed thrombus at 28 days follow-up. The rabbits treated with standard stents showed an increase in TDC residency time after treatment and partial-thrombogenesis. The untreated control aneurysms displayed no reduction in flow and were still patent at follow-up. The quantitative TDC analysis findings were confirmed by histological evaluation suggesting that the new AVS has great potential as a definitive treatment for cerebro-vascular aneurysms and that angiographic TDC analysis can provide in-vivo verification.

Endovascular image-guided treatment of in-vivo model aneurysms with asymmetric vascular stents (AVS): evaluation with time-density curve angiographic analysis and histology

PubMed Central

Dohatcu, A.; Ionita, C. N.; Paciorek, A.; Bednarek, D. R.; Hoffmann, K. R.; Rudin, S.

2008-01-01

In this study, we compare the results obtained from Time-Density Curve (TDC) analysis of angiographic imaging sequences with histological evaluation for a rabbit aneurysm model treated with standard stents and new asymmetric vascular stents (AVS) placed by image-guided endovascular deployment. AVSs are stents having a low-porosity patch region designed to cover the aneurysm neck and occlude blood flow inside. To evaluate the AVSs, rabbits with elastase-induced aneurysm models (n=20) were divided into three groups: the first (n=10) was treated with an AVS, the second (n=5) with a non-patch standard coronary stent, and third was untreated as a control (n=5). We used TDC analysis to measure how much contrast media entered the aneurysm before and after treatment. TDCs track contrast-media-density changes as a function of time over the region of interest in x-ray DSA cine-sequences. After 28 days, the animals were sacrificed and the explanted specimens were histologically evaluated. The first group showed an average reduction of contrast flow into the aneurysm of 95% after treatment with an AVS with fully developed thrombus at 28 days follow-up. The rabbits treated with standard stents showed an increase in TDC residency time after treatment and partial-thrombogenesis. The untreated control aneurysms displayed no reduction in flow and were still patent at follow-up. The quantitative TDC analysis findings were confirmed by histological evaluation suggesting that the new AVS has great potential as a definitive treatment for cerebro-vascular aneurysms and that angiographic TDC analysis can provide in-vivo verification. PMID:18958295

Octogenarians Undergoing Open Repair Have Higher Mortality Compared with Fenestrated Endovascular Repair of Intact Abdominal Aortic Aneurysms Involving the Visceral Vessels.

PubMed

Locham, Satinderjit; Faateh, Muhammad; Dakour-Aridi, Hanaa; Nejim, Besma; Malas, Mahmoud

2018-04-18

Prior studies have shown that octogenarians have a higher risk of mortality than nonoctogenarians undergoing open aneurysm repair (OAR) and endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA). Fenestrated endovascular aneurysm repair (F-EVAR) was approved by the Food and Drug Administration (FDA) in 2012 and has been used as a less invasive approach to treat patients with suboptimal neck anatomy with favorable outcomes compared with traditional OAR. The aim of the study is to compare 30-day outcomes of F-EVAR versus OAR in octogenarians undergoing repair of AAA involving the visceral vessels in the United States. All patients with postoperative diagnosis of nonruptured AAA repair were identified in the National Surgical Quality Improvement Program database (2006-2015). Univariate and multivariate analyses were implemented to examine 30-day morbidity and mortality adjusting for patient demographics and comorbidities. A total of 548 octogenarians underwent repair of nonruptured AAA involving the visceral vessels, of which 242 (44%) were F-EVARs, and 306 (56%) were OARs. Octogenarians undergoing F-EVAR were on average 1-year older (median age [interquartile range]: 83 [82, 86] versus 82 [81, 85], P = 0.004) and more likely to be male (82% vs. 64%, P < 0.001) compared with OAR. Prevalence of diabetes (13% vs. 6%, P = 0.005) and progressive renal failure (57% vs. 47%, P = 0.03) was also higher in patients undergoing F-EVAR compared with OAR. Thirty-day postoperative mortality was higher after OAR (8.5% vs. 4.1%, P = 0.04). Secondary outcomes including cardiopulmonary (27.1% vs. 5.8%, P < 0.001) and renal injury (10.8% vs. 2.1%, P < 0.001) were also significantly higher in OAR compared with F-EVAR. After adjusting for patients' demographics and comorbidities, OAR had almost 4-fold increased risk of 30-day postoperative mortality compared with F-EVAR (odds ratio [95% confidence interval]: 3.90 [1.48-10.31], P = 0.006). In this large national cohort of octogenarians undergoing repair for complex AAA's, we showed that F-EVAR is associated with significantly lower postoperative morbidity and mortality than open repair. One of the main limitations of the study is the lack of anatomical data. However, despite that, our findings support the shifting paradigm toward minimally invasive approach in this frail population for treatment of complex AAA's. Further studies are needed to evaluate the long-term benefit of any repair in octogenarians. Copyright © 2018 Elsevier Inc. All rights reserved.

Lessons learned from whole exome sequencing in multiplex families affected by a complex genetic disorder, intracranial aneurysm.

PubMed

Farlow, Janice L; Lin, Hai; Sauerbeck, Laura; Lai, Dongbing; Koller, Daniel L; Pugh, Elizabeth; Hetrick, Kurt; Ling, Hua; Kleinloog, Rachel; van der Vlies, Pieter; Deelen, Patrick; Swertz, Morris A; Verweij, Bon H; Regli, Luca; Rinkel, Gabriel J E; Ruigrok, Ynte M; Doheny, Kimberly; Liu, Yunlong; Broderick, Joseph; Foroud, Tatiana

2015-01-01

Genetic risk factors for intracranial aneurysm (IA) are not yet fully understood. Genomewide association studies have been successful at identifying common variants; however, the role of rare variation in IA susceptibility has not been fully explored. In this study, we report the use of whole exome sequencing (WES) in seven densely-affected families (45 individuals) recruited as part of the Familial Intracranial Aneurysm study. WES variants were prioritized by functional prediction, frequency, predicted pathogenicity, and segregation within families. Using these criteria, 68 variants in 68 genes were prioritized across the seven families. Of the genes that were expressed in IA tissue, one gene (TMEM132B) was differentially expressed in aneurysmal samples (n=44) as compared to control samples (n=16) (false discovery rate adjusted p-value=0.023). We demonstrate that sequencing of densely affected families permits exploration of the role of rare variants in a relatively common disease such as IA, although there are important study design considerations for applying sequencing to complex disorders. In this study, we explore methods of WES variant prioritization, including the incorporation of unaffected individuals, multipoint linkage analysis, biological pathway information, and transcriptome profiling. Further studies are needed to validate and characterize the set of variants and genes identified in this study.

Flow modification in canine intracranial aneurysm model by an asymmetric stent: studies using digital subtraction angiography (DSA) and image-based computational fluid dynamics (CFD) analyses

NASA Astrophysics Data System (ADS)

Hoi, Yiemeng; Ionita, Ciprian N.; Tranquebar, Rekha V.; Hoffmann, Kenneth R.; Woodward, Scott H.; Taulbee, Dale B.; Meng, Hui; Rudin, Stephen

2006-03-01

An asymmetric stent with low porosity patch across the intracranial aneurysm neck and high porosity elsewhere is designed to modify the flow to result in thrombogenesis and occlusion of the aneurysm and yet to reduce the possibility of also occluding adjacent perforator vessels. The purposes of this study are to evaluate the flow field induced by an asymmetric stent using both numerical and digital subtraction angiography (DSA) methods and to quantify the flow dynamics of an asymmetric stent in an in vivo aneurysm model. We created a vein-pouch aneurysm model on the canine carotid artery. An asymmetric stent was implanted at the aneurysm, with 25% porosity across the aneurysm neck and 80% porosity elsewhere. The aneurysm geometry, before and after stent implantation, was acquired using cone beam CT and reconstructed for computational fluid dynamics (CFD) analysis. Both steady-state and pulsatile flow conditions using the measured waveforms from the aneurysm model were studied. To reduce computational costs, we modeled the asymmetric stent effect by specifying a pressure drop over the layer across the aneurysm orifice where the low porosity patch was located. From the CFD results, we found the asymmetric stent reduced the inflow into the aneurysm by 51%, and appeared to create a stasis-like environment which favors thrombus formation. The DSA sequences also showed substantial flow reduction into the aneurysm. Asymmetric stents may be a viable image guided intervention for treating intracranial aneurysms with desired flow modification features.

Transcatheter Coil Embolization of Splenic Artery Aneurysm

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamamoto, Satoshi, E-mail: s-yama@hyo-med.ac.jp; Hirota, Shozo; Maeda, Hiroaki

2008-05-15

The purpose of this study was to evaluate clinical results and technical problems of transcatheter coil embolization for splenic artery aneurysm. Subjects were 16 patients (8 men, 8 women; age range, 40-80 years) who underwent transcatheter embolization for splenic artery aneurysm (14 true aneurysms, 2 false aneurysms) at one of our hospitals during the period January 1997 through July 2005. Two aneurysms (12.5%) were diagnosed at the time of rupture. Multiple splenic aneurysms were found in seven patients. Aneurysms were classified by site as proximal (or strictly ostial) (n = 3), middle (n = 3), or hilar (n = 10).more » The indication for transcatheter arterial embolization was a false or true aneurysm 20 mm in diameter. Embolic materials were fibered coils and interlocking detachable coils. Embolization was performed by the isolation technique, the packing technique, or both. Technically, all aneurysms were devascularized without severe complications. Embolized aneurysms were 6-40 mm in diameter (mean, 25 mm). Overall, the primary technical success rate was 88% (14 of 16 patients). In the remaining 2 patients (12.5%), partial recanalization occurred, and re-embolization was performed. The secondary technical success rate was 100%. Seven (44%) of the 16 study patients suffered partial splenic infarction. Intrasplenic branching originating from the aneurysm was observed in five patients. We conclude that transcatheter coil embolization should be the initial treatment of choice for splenic artery aneurysm.« less

Risk of recurrent subarachnoid haemorrhage, death, or dependence and standardised mortality ratios after clipping or coiling of an intracranial aneurysm in the International Subarachnoid Aneurysm Trial (ISAT): long-term follow-up

PubMed Central

Molyneux, Andrew J; Kerr, Richard SC; Birks, Jacqueline; Ramzi, Najib; Yarnold, Julia; Sneade, Mary; Rischmiller, Joan

2009-01-01

Summary Background Our aim was to assess the long-term risks of death, disability, and rebleeding in patients randomly assigned to clipping or endovascular coiling after rupture of an intracranial aneurysm in the follow-up of the International Subarachnoid Aneurysm Trial (ISAT). Methods 2143 patients with ruptured intracranial aneurysms were enrolled between 1994 and 2002 at 43 neurosurgical centres and randomly assigned to clipping or coiling. Clinical outcomes at 1 year have been previously reported. All UK and some non-UK centres continued long-term follow-up of 2004 patients enrolled in the original cohort. Annual follow-up has been done for a minimum of 6 years and a maximum of 14 years (mean follow-up 9 years). All deaths and rebleeding events were recorded. Analysis of rebleeding was by allocation and by treatment received. ISAT is registered, number ISRCTN49866681. Findings 24 rebleeds had occurred more than 1 year after treatment. Of these, 13 were from the treated aneurysm (ten in the coiling group and three in the clipping group; log rank p=0·06 by intention-to-treat analysis). There were 8447 person-years of follow-up in the coiling group and 8177 person-years of follow-up in the clipping group. Four rebleeds occurred from a pre-existing aneurysm and six from new aneurysms. At 5 years, 11% (112 of 1046) of the patients in the endovascular group and 14% (144 of 1041) of the patients in the neurosurgical group had died (log-rank p=0·03). The risk of death at 5 years was significantly lower in the coiling group than in the clipping group (relative risk 0·77, 95% CI 0·61–0·98; p=0·03), but the proportion of survivors at 5 years who were independent did not differ between the two groups: endovascular 83% (626 of 755) and neurosurgical 82% (584 of 713). The standardised mortality rate, conditional on survival at 1 year, was increased for patients treated for ruptured aneurysms compared with the general population (1·57, 95% CI 1·32–1·82; p<0·0001). Interpretation There was an increased risk of recurrent bleeding from a coiled aneurysm compared with a clipped aneurysm, but the risks were small. The risk of death at 5 years was significantly lower in the coiled group than it was in the clipped group. The standardised mortality rate for patients treated for ruptured aneurysms was increased compared with the general population. Funding UK Medical Research Council. PMID:19329361

Time-resolved imaging of contrast kinetics does not improve performance of follow-up MRA of embolized intracranial aneurysms.

PubMed

Serafin, Zbigniew; Strześniewski, Piotr; Lasek, Władysław; Beuth, Wojciech

2012-07-01

The use of contrast media and the time-resolved imaging of contrast kinetics (TRICKS) technique have some theoretical advantages over time-of-flight magnetic resonance angiography (TOF-MRA) in the follow-up of intracranial aneurysms after endovascular treatment. We prospectively compared the diagnostic performance of TRICKS and TOF-MRA with digital subtracted angiography (DSA) in the assessment of occlusion of embolized aneurysms. Seventy-two consecutive patients with 72 aneurysms were examined 3 months after embolization. Test characteristics of TOF-MRA and TRICKS were calculated for the detection of residual flow. The results of quantification of flow were compared with weighted kappa. Intraobserver and interobserver reproducibility was determined. The sensitivity of TOF-MRA was 85% (95% CI, 65-96%) and of TRICKS, 89% (95% CI, 70-97%). The specificity of both methods was 91% (95% CI, 79-98%). The accuracy of the flow quantification ranged from 0.76 (TOF-MRA) to 0.83 (TRICKS). There was no significant difference between the methods in the area under the ROC curve regarding both the detection and the quantification of flow. Intraobserver reproducibility was very good with both techniques (kappa, 0.86-0.89). The interobserver reproducibility was moderate for TOF-MRA and very good for TRICKS (kappa, 0.74-0.80). In this study, TOF-MRA and TRICKS presented similar diagnostic performance; therefore, the use of time-resolved contrast-enhanced MRA is not justified in the follow-up of embolized aneurysms.

Does specialization improve outcome in abdominal aortic aneurysm surgery?

PubMed

Rosenthal, Rachel; von Känel, Oliver; Eugster, Thomas; Stierli, Peter; Gürke, Lorenz

2005-01-01

Specialization and high volume are reported to be related to a better outcome after abdominal aortic aneurysm repair. The aim of this study was to compare, in patients undergoing abdominal aortic aneurysm repair, the outcomes of those whose surgery was done by general surgeons with the outcomes of those whose surgery was done by specialist vascular surgeons. All patients undergoing abdominal aortic aneurysm repair at the Basel University Hospital (referral center) from January 1990 to December 2000 were included. Patients with endovascular treatment were excluded. Operations in group A (n = 189), between January 1990 and May 1995, were done by general surgeons. Operations in group B (n = 291), between June 1995 and December 2000, were done by vascular surgeons. In-hospital mortality and local and systemic complications were assessed. In-hospital mortality rates were significantly lower for group B (with specialist surgeons) than for group A, both overall (group B, 11.7%; group A, 21.7%; p = .003) and for emergency interventions (group B, 28.1%; group A, 41.9%; p = .042). The reduction in mortality for elective surgery in group B was not statistically significant (group B, 1.1%; group A, 4.9%; p = .054). There were significantly fewer pulmonary complications in group B compared with group A (p = .000). We conclude that in patients undergoing abdominal aortic aneurysm repair, those whose surgery is done by a specialized team have a significantly better outcome than those whose surgery is done by general surgeons.

Mechanisms of Healing in Coiled Intracranial Aneurysms: A Review of the Literature

PubMed Central

Brinjikji, Waleed; Kallmes, David F; Kadirvel, Ramanathan

2016-01-01

Summary Recanalization of intracranial aneurysms following endovascular coiling remains a frustratingly common occurrence. An understanding of the molecular and histopathological mechanisms of aneurysm healing following coil embolization is essential to improving aneurysm occlusion rates. Histolopathologic studies in coiled human and experimental aneurysms suggest that during the first month post-coiling, thrombus formation and active inflammation occur within the aneurysm dome. Several months following embolization, the aneurysm is excluded from the parent vessel by formation of a neointimal layer, which is often thin and discontinuous, across the aneurysm neck. Numerous coil modifications and systemic therapies have been tested in animals and humans in an attempt to improve the aneurysm healing process; these modifications have met with variable levels of success. In this review, we summarize the histopathologic and molecular biology of aneurysm healing and discuss how these findings have been applied in an attempt to improve angiographic outcomes in patients harboring intracranial aneurysm. PMID:25430855

True aneurysms of the posterior communicating artery: a systematic review and meta-analysis of individual patient data.

PubMed

He, Wenzhuan; Gandhi, Chirag D; Quinn, John; Karimi, Reza; Prestigiacomo, Charles J

2011-01-01

To review and analyze systematically the reported cases of "true" posterior communicating artery (PCoA) aneurysm. A retrospective review of the published literature was performed, and a meta-analysis of individual patient data was conducted. Pooled data showed that "true" PCoA aneurysms represent about 1.3% (95% confidence interval [CI] 0.8%, 1.7%) of all intracranial aneurysms and 6.8% (95% CI 4.3%, 9.2%) of all PCoA aneurysms. Mean patient age was 53.5 years (53.5 years ± 15.4), and age range was 23-79 years. Of the 49 patients reported in the literature, 44 (89.8%) were reported as ruptured, and 4 (10.2%) were reported as unruptured. There were no significant differences in ruptured status between age (P = 0.321), left vs right aneurysm (P = 0.537), and shape of aneurysm (P = 0.408). No significant differences in complication rates were found between rupture status (P = 0.27), and operative modalities (P = 0.878). The mean ages of patients who had no complications and patients who had complications were 53 years (53 years ± 2.59) vs 53.2 years (53.2 years ± 5.02) (P = 0.972). "True" PCoA aneurysms represent about 1.3% of all intracranial aneurysms and 6.8% of all PCoA aneurysms. They are more prone to rupture compared with their counterpart junctional aneurysms. When surgical management is indicated, a good understanding of the location and configuration of the aneurysm neck before surgical treatment is critical in the successful treatment of these lesions. Copyright © 2011 Elsevier Inc. All rights reserved.

Physiologically-relevant measurements of flow through coils and stents: towards improved modeling of endovascular treatment of intracranial aneurysms

NASA Astrophysics Data System (ADS)

Barbour, Michael; Levitt, Michael; Geindreau, Christian; Rolland Du Roscoat, Sabine; Johnson, Luke; Chivukula, Keshav; Aliseda, Alberto

2016-11-01

The hemodynamic environment in cerebral aneurysms undergoing flow-diverting stent (FDS) or coil embolization treatment plays a critical role in long-term outcomes. Standard modeling approaches to endovascular coils and FDS simplify the complex geometry into a homogenous porous volume or surface through the addition of a Darcy-Brinkman pressure loss term in the momentum equation. The inertial and viscous loss coefficients are typically derived from published in vitro studies of pressure loss across FDS and coils placed in a straight tube, where the only fluid path is across the treatment - an unrealistic representation of treatment apposition in vivo. The pressure drop across FDS and coils in side branch aneurysms located on curved parent vessels is measured. Using PIV, the velocity at the aneurysm neck plane is reconstructed and used to determine loss coefficients for better models of endovascular coils or FDS that account for physiological placement and vessel curvature. These improved models are incorporated into CFD simulations and validated against in vitro model PIV velocity, as well as compared to microCT-based coil/stent-resolving CFD simulations of patient-specific treated aneurysm flow.

Use of the stereoscopic virtual reality display system for the detection and characterization of intracranial aneurysms: A Icomparison with conventional computed tomography workstation and 3D rotational angiography.

PubMed

Liu, Xiujuan; Tao, Haiquan; Xiao, Xigang; Guo, Binbin; Xu, Shangcai; Sun, Na; Li, Maotong; Xie, Li; Wu, Changjun

2018-07-01

This study aimed to compare the diagnostic performance of the stereoscopic virtual reality display system with the conventional computed tomography (CT) workstation and three-dimensional rotational angiography (3DRA) for intracranial aneurysm detection and characterization, with a focus on small aneurysms and those near the bone. First, 42 patients with suspected intracranial aneurysms underwent both 256-row CT angiography (CTA) and 3DRA. Volume rendering (VR) images were captured using the conventional CT workstation. Next, VR images were transferred to the stereoscopic virtual reality display system. Two radiologists independently assessed the results that were obtained using the conventional CT workstation and stereoscopic virtual reality display system. The 3DRA results were considered as the ultimate reference standard. Based on 3DRA images, 38 aneurysms were confirmed in 42 patients. Two cases were misdiagnosed and 1 was missed when the traditional CT workstation was used. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the conventional CT workstation were 94.7%, 85.7%, 97.3%, 75%, and99.3%, respectively, on a per-aneurysm basis. The stereoscopic virtual reality display system missed a case. The sensitivity, specificity, PPV, NPV, and accuracy of the stereoscopic virtual reality display system were 100%, 85.7%, 97.4%, 100%, and 97.8%, respectively. No difference was observed in the accuracy of the traditional CT workstation, stereoscopic virtual reality display system, and 3DRA in detecting aneurysms. The stereoscopic virtual reality display system has some advantages in detecting small aneurysms and those near the bone. The virtual reality stereoscopic vision obtained through the system was found as a useful tool in intracranial aneurysm diagnosis and pre-operative 3D imaging. Copyright © 2018 Elsevier B.V. All rights reserved.

An outcomes-based grading scale for the evaluation of cerebral aneurysms treated with flow diversion.

PubMed

Park, Min S; Mazur, Marcus D; Moon, Karam; Nanaszko, Michael J; Kestle, John R W; Shah, Lubdha M; Winegar, Blair; Albuquerque, Felipe C; Taussky, Philipp; McDougall, Cameron G

2017-11-01

Despite the popularity of flow-diverting stents for the treatment of cerebral aneurysms, there is no widely accepted scale for the characterization of results. We present an outcomes-based grading scale that considers factors related to failure of flow diversion. The grading scale was developed using the results from consecutive patients at two institutions who were treated with flow diversion for a cerebral aneurysm. The initial treatment results were graded on patient, aneurysm, and treatment characteristics. A 6-point grading scale was developed based on these data. One hundred and seventy-one patients were included in the patient cohort. When compared by multivariate analysis with patients without residuals, patients with aneurysm residuals were found to be older (age ≥60 years, p=0.01, OR 1.17, 95% CI 1.03 to 1.33), to have larger aneurysms (size ≥15 mm, p<0.01, OR 1.38, 95% CI 1.17 to 1.62), to have aneurysms with associated side branches (p=0.02, OR 1.17, 95% CI 1.03 to 1.33), and to have a post-treatment Raymond score of 2 or 3 (p=0.01, OR 1.28, 95% CI 1.06 to 1.56). Using the Raymond score (1-3) as the foundation for the grading scale, additional points (0 or 1) were given for the other three identified factors, creating a 6-point scale. We found that patients with residual aneurysms had statistically higher final tabulated scores (p<0.01). We propose a novel straightforward outcomes-based scale to characterize results after flow diversion treatment of cerebral aneurysms. This scale may provide the basis for the common reporting of results in future studies. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Multiple sites of vascular dilation or aneurysmal disease and matrix metalloproteinase genetic variants in patients with abdominal aortic aneurysm.

PubMed

Fiotti, Nicola; Calvagna, Cristiano; Sgorlon, Giada; Altamura, Nicola; Pitacco, Paola; Zamolo, Francesca; Di Girolamo, Filippo Giorgio; Chiarandini, Stefano; Biolo, Gianni; Adovasio, Roberto

2018-06-01

The objective of this study was to assess whether functional genetic polymorphisms of matrix metalloproteinases (MMPs) 1, 3, 9, and 12 are associated with arterial enlargements or aneurysms of the thoracic aorta or popliteal arteries in patients with abdominal aortic aneurysm (AAA). The associations between MMP1 (-1607 G in/del, rs1799750), MMP3 (-1171 A in/del rs35068180), MMP9 (13-26 CA repeats around -90, rs2234681, rs917576, rs917577), and MMP12 (G/T missense variation, rs652438) polymorphisms and enlargements or aneurysms of the thoracic aorta and popliteal arteries were tested in 169 consecutive AAA patients. Thoracic aorta enlargement or aneurysm (TE/A; maximum diameter, >35 mm) was detected in 34 patients (20.1% prevalence). MMP9 rs2234681 microsatellite was the only genetic determinant of TE/A in AAA patients (P = .003), followed by hypercholesterolemia and antiplatelet use. Carriers of both alleles with ≥22 CA repeats had a 5.9 (95% confidence interval, 1.9-18.6; P < .0001) increased odds of TE/A, and a score considering all three variables showed 98% negative predictive value and 30% positive predictive value for thoracic aortic aneurysm detection. Eighty-two popliteal artery enlargements or aneurysms (diameter >10 mm) occurred in 55 patients (33.1% prevalence). Carriers of MMP12 rs652438 C allele showed an 18% (P = .006) increased diameter in popliteal arteries and a 2.8 (95% confidence interval, 1.3-6; P = .008) increased odds of popliteal artery enlargement or aneurysm compared with TT genotype. Among patients with AAA, carriers of homozygous ≥22 CA repeats in MMP9 rs12234681 and of C allele in MMP12 rs652438 have a substantial risk of carrying thoracic and popliteal enlargements, respectively. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Ultra-low-dose computed tomographic angiography with model-based iterative reconstruction compared with standard-dose imaging after endovascular aneurysm repair: a prospective pilot study.

PubMed

Naidu, Sailen G; Kriegshauser, J Scott; Paden, Robert G; He, Miao; Wu, Qing; Hara, Amy K

2014-12-01

An ultra-low-dose radiation protocol reconstructed with model-based iterative reconstruction was compared with our standard-dose protocol. This prospective study evaluated 20 men undergoing surveillance-enhanced computed tomography after endovascular aneurysm repair. All patients underwent standard-dose and ultra-low-dose venous phase imaging; images were compared after reconstruction with filtered back projection, adaptive statistical iterative reconstruction, and model-based iterative reconstruction. Objective measures of aortic contrast attenuation and image noise were averaged. Images were subjectively assessed (1 = worst, 5 = best) for diagnostic confidence, image noise, and vessel sharpness. Aneurysm sac diameter and endoleak detection were compared. Quantitative image noise was 26% less with ultra-low-dose model-based iterative reconstruction than with standard-dose adaptive statistical iterative reconstruction and 58% less than with ultra-low-dose adaptive statistical iterative reconstruction. Average subjective noise scores were not different between ultra-low-dose model-based iterative reconstruction and standard-dose adaptive statistical iterative reconstruction (3.8 vs. 4.0, P = .25). Subjective scores for diagnostic confidence were better with standard-dose adaptive statistical iterative reconstruction than with ultra-low-dose model-based iterative reconstruction (4.4 vs. 4.0, P = .002). Vessel sharpness was decreased with ultra-low-dose model-based iterative reconstruction compared with standard-dose adaptive statistical iterative reconstruction (3.3 vs. 4.1, P < .0001). Ultra-low-dose model-based iterative reconstruction and standard-dose adaptive statistical iterative reconstruction aneurysm sac diameters were not significantly different (4.9 vs. 4.9 cm); concordance for the presence of endoleak was 100% (P < .001). Compared with a standard-dose technique, an ultra-low-dose model-based iterative reconstruction protocol provides comparable image quality and diagnostic assessment at a 73% lower radiation dose.

Cytokine and growth factor concentration in cerebrospinal fluid from patients with hydrocephalus following endovascular embolization of unruptured aneurysms in comparison with other types of hydrocephalus.

PubMed

Killer, Monika; Arthur, Adam; Al-Schameri, Abdul Rahman; Barr, John; Elbert, Donald; Ladurner, Gunther; Shum, Julie; Cruise, Gregory

2010-10-01

To better understand the development of hydrocephalus of different origins, we evaluated cytokine and growth factor concentration in cerebrospinal fluid from patients with hydrocephalus. CSF was collected from patients developing hydrocephalus following hemorrhage (n = 15), patients with normal pressure hydrocephalus (n = 10), and following the embolization of unruptured intracranial aneurysms (n = 9). Myelography patients (n = 15) served as controls. Quantification of 11 molecules relating angiogenesis, inflammation, and wound healing in the CSF was performed using ELISA. All three hydrocephalus groups had decreased concentration of TIMP-4 compared to the normal group. The hemorrhage group showed increased concentration of IL-6, IL-8, MCP-1, MMP-9, and TIMP-1 compared to the control group. The unruptured aneurysm group had increased concentration of IL-6 and decreased concentration of TIMP-2 compared to the control group. Compared to the normal patients, increased concentrations of wound healing molecules were evident in all three groups. Increased inflammation was evident in the hemorrhage and unruptured aneurysm groups.

Safety and efficacy of aneurysm treatment with WEB in the cumulative population of three prospective, multicenter series.

PubMed

Pierot, Laurent; Moret, Jacques; Barreau, Xavier; Szikora, Istvan; Herbreteau, Denis; Turjman, Francis; Holtmannspötter, Markus; Januel, Anne-Christine; Costalat, Vincent; Fiehler, Jens; Klisch, Joachim; Gauvrit, Jean-Yves; Weber, Werner; Desal, Hubert; Velasco, Stéphane; Liebig, Thomas; Stockx, Luc; Berkefeld, Joachim; Molyneux, Andrew; Byrne, James; Spelle, Laurent

2018-06-01

Flow disruption with the WEB is an innovative endovascular approach for treatment of wide-neck bifurcation aneurysms. Initial studies have shown a low complication rate with good efficacy. To report clinical and anatomical results of the WEB treatment in the cumulative population of three Good Clinical Practice (GCP) studies: WEBCAST (WEB Clinical Assessment of Intrasaccular Aneurysm), French Observatory, and WEBCAST-2. WEBCAST, French Observatory, and WEBCAST-2 are single-arm, prospective, multicenter, GCP studies dedicated to the evaluation of WEB treatment. Clinical data were independently evaluated. Postoperative and 1-year aneurysm occlusion was independently evaluated using the 3-grade scale: complete occlusion, neck remnant, and aneurysm remnant. The cumulative population comprised 168 patients with 169 aneurysms, including 112 female subjects (66.7%). The patients' ages ranged between 27 and 77 years (mean 55.5±10.2 years). Aneurysm locations were middle cerebral artery in 86/169 aneurysms (50.9%), anterior communicating artery in 36/169 (21.3%), basilar artery in 30/169 (17.8%), and internal carotid artery terminus in 17/169 (10.1%). The aneurysm was ruptured in 14/169 (8.3%). There was no mortality at 1 month and procedure/device-related morbidity was 1.2% (2/168). At 1 year, complete aneurysm occlusion was observed in 81/153 aneurysms (52.9%), neck remnant in 40/153 aneurysms (26.1%), and aneurysm remnant in 32/153 aneurysms (20.9%). Re-treatment was carried out in 6.9%. This series is at the moment the largest prospective, multicenter, GCP series of patients with aneurysms treated with WEB. It shows the high safety and good mid-term efficacy of this treatment. French Observatory: Unique identifier (NCT18069); WEBCAST and WEBCAST-2: Unique identifier (NCT01778322). © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Application of Micromirror in Microsurgical Clipping to the Intracranial Aneurysms.

PubMed

Zhao, Chao; Ma, Zhiguo; Zhang, Yuhai; Mou, Shanling; Yang, Yunxue; Yang, Yonglin; Sun, Guoqing; Yao, Weicheng

2018-05-01

The aim of the study was to explore the values and disadvantages of micromirror in the intracranial aneurysm clipping surgery. Micromirror was used to assist microsurgical clipping to 36 intracranial aneurysms in 31 patients, of which 3 were carotid-ophthalmic artery aneurysms, 3 were anterior choroidal artery aneurysms, 11 were posterior communicating artery aneurysms, 7 were middle cerebral artery aneurysms, 10 were anterior communicating artery or anterior cerebral artery aneurysms, and the rest were a posterior cerebral artery aneurysm and a posterior inferior cerebellar artery aneurysm. The micromirror was used before and after clipping to observe the anatomic features of necks hidden behind and medial to aneurysms, to visualize surrounding neurovascular structures, and to verify the optimal clipping position. Intraoperative indocyanine green fluorescein angiography, postoperative computerized tomography angiography, and digital subtraction angiography confirmed the success of sufficient clipping. Intraoperative indocyanine green angiography, postoperative computerized tomography angiography , or digital subtraction angiography were performed and showed no case of wrong or insufficient clipping of aneurysm. Micromirror-assisted microsurgical clipping to the intracranial aneurysm is safe, sufficient, convenient, and practical.

Point-of-care ultrasound performed by a medical student compared to physical examination by vascular surgeons in the detection of abdominal aortic aneurysms.

PubMed

Mai, Trinh; Woo, Michael Y; Boles, Kim; Jetty, Prasad

2018-05-16

To determine the test characteristics of point-of-care ultrasonography performed by a medical student versus physical examination by vascular surgeons compared to a gold standard reference scan for the detection of abdominal aortic aneurysms. We conducted a prospective, observer-blinded study recruiting patients from an outpatient vascular surgery clinic. Participants were screened for abdominal aortic aneurysms by standardized physical examination by a blinded vascular surgeon, followed by a point-of-care ultrasound examination by a blinded medical student. The student underwent prior training by a vascular sonographer and emergency physician on 60 patients (16 were supervised). Ultrasonography was used to visualize and measure the proximal, mid, and distal aortic diameters. The maximal aortic diameter was noted and compared to measurements obtained by the reference scan (CT scan or vascular sonographer-performed ultrasound). Reference scans were completed within 3 months of the recruitment visit. A total of 57 patients were enrolled over a 5-month period between October 2015 and March 2016. Mean age of recruited patients was 71 years and 61% were male. Mean body mass index was 27.9 ± 4.3 and mean waist-hip ratio was 0.96 ± 0.10. Sixteen abdominal aortic aneurysms were detected by the reference scan, with an average maximal aortic diameter of 44.9 mm. Physical examination by a vascular surgeon detected 11 of 16 abdominal aortic aneurysms with 2 false positives (sensitivity and specificity of 66.7% (95% CI 38.4-88.2) and 94.4% (95% CI 81.3-99.3), respectively). Point-of-care ultrasound detected 15 of 16 abdominal aortic aneurysms (sensitivity and specificity of 93.3% (95% CI 68.1-99.8) and 100% (95% CI 88.4-100), respectively). Seven of the 64 point-of-care ultrasound scans were indeterminate (>1 cm of the aorta was not visualized). Average time to conduct the physical examination was 35 seconds vs. 4.0 minutes for point-of-care ultrasonography. There was a strong linear correlation (R2=0.95) between maximal aortic diameter measured by point-of-care ultrasonography vs referencescan with a mean absolute difference of 2.6 mm. Point-of-care ultrasonography performed by a medical student is highly accurate and more effective in detecting abdominal aortic aneurysms when compared to physical examination by vascular surgeons. The introduction of point-of-care ultrasound training at the medical student level, and its wide-scale implementation as an extension to physical examination, may lead to improved detection of abdominal aortic aneurysms. Copyright © 2018. Published by Elsevier Inc.

Textbook Outcome: A Composite Measure for Quality of Elective Aneurysm Surgery.

PubMed

Karthaus, Eleonora G; Lijftogt, Niki; Busweiler, Linde A D; Elsman, Bernard H P; Wouters, Michel W J M; Vahl, Anco C; Hamming, Jaap F

2017-11-01

To investigate a new composite quality measurement, which comprises a desirable outcome for elective aneurysm surgery, called "Textbook Outcome" (TO). Single-quality indicators in vascular surgery are often not distinctive and insufficiently reflect the quality of care. All patients undergoing elective abdominal aortic aneurysm repair, registered in the Dutch Surgical Aneurysm Audit between 2014 and 2015 were included. TO was defined as the percentage of patients who had abdominal aortic aneurysm-repair without intraoperative complications, postoperative surgical complications, reinterventions, prolonged hospital stay [endovascular aneurysm repair (EVAR) ≤4 d, open surgical repair (OSR) ≤10 d], readmissions, and postoperative mortality (≤30 d after surgery/at discharge). Case-mix adjusted TO rates were used to compare hospitals and to compare individual hospital results for different procedures. Five thousand one hundred seventy patients were included, of whom 4039 were treated with EVAR and 1131 with OSR. TO was achieved in 71% of EVAR and 53% of OSR. Important obstacles for achieving TO were a prolonged hospital stay, postoperative complications, and readmissions. Adjusted TO rates varied from 38% to 89% (EVAR) and from 0% to 97% (OSR) between individual hospitals. Hospitals with a high TO for OSR also had a high TO for EVAR; however, a high TO for EVAR did not implicate a high TO for OSR. TO generates additional information to evaluate the overall quality of the care of elective aneurysm surgery, which subsequently can be used by hospitals to improve the quality of their care.

EARLYDRAIN- outcome after early lumbar CSF-drainage in aneurysmal subarachnoid hemorrhage: study protocol for a randomized controlled trial.

PubMed

Bardutzky, Jürgen; Witsch, Jens; Jüttler, Eric; Schwab, Stefan; Vajkoczy, Peter; Wolf, Stefan

2011-09-14

Aneurysmal subarachnoid hemorrhage (SAH) may be complicated by delayed cerebral ischemia, which is a major cause of unfavorable clinical outcome and death in SAH-patients. Delayed cerebral ischemia is presumably related to the development of vasospasm triggered by the presence of blood in the basal cisterns. To date, oral application of the calcium antagonist nimodipine is the only prophylactic treatment for vasospasm recognized under international guidelines.In retrospective trials lumbar drainage of cerebrospinal fluid has been shown to be a safe and feasible measure to remove the blood from the basal cisterns and decrease the incidence of delayed cerebral ischemia and vasospasm in the respective study populations. However, the efficacy of lumbar drainage has not been evaluated prospectively in a randomized controlled trial yet. This is a protocol for a 2-arm randomized controlled trial to compare an intervention group receiving early continuous lumbar CSF-drainage and standard neurointensive care to a control group receiving standard neurointensive care only. Adults suffering from a first aneurysmal subarachnoid hemorrhage whose aneurysm has been secured by means of coiling or clipping are eligible for trial participation. The effect of early CSF drainage (starting < 72 h after securing the aneurysm) will be measured in the following ways: the primary endpoint will be disability after 6 months, assessed by a blinded investigator during a personal visit or standardized telephone interview using the modified Rankin Scale. Secondary endpoints include mortality after 6 months, angiographic vasospasm, transcranial Doppler sonography (TCD) mean flow velocity in both middle cerebral arteries and rate of shunt insertion at 6 months after hospital discharge. Here, we present the study design of a multicenter prospective randomized controlled trial to investigate whether early application of a lumbar drainage improves clinical outcome after aneurysmal subarachnoid hemorrhage.

Safety, efficacy, and cost of intraoperative indocyanine green angiography compared to intraoperative catheter angiography in cerebral aneurysm surgery.

PubMed

Hardesty, Douglas A; Thind, Harjot; Zabramski, Joseph M; Spetzler, Robert F; Nakaji, Peter

2014-08-01

Intraoperative angiography in cerebrovascular neurosurgery can drive the repositioning or addition of aneurysm clips. Our institution has switched from a strategy of intraoperative digital subtraction angiography (DSA) universally, to a strategy of indocyanine green (ICG) videoangiography with DSA on an as-needed basis. We retrospectively evaluated whether the rates of perioperative stroke, unexpected postoperative aneurysm residual, or parent vessel stenosis differed in 100 patients from each era (2002, "DSA era"; 2007, "ICG era"). The clip repositioning rate for neck residual or parent vessel stenosis did not differ significantly between the two eras. There were no differences in the rate of perioperative stroke or rate of false-negative studies. The per-patient cost of intraoperative imaging within the DSA era was significantly higher than in the ICG era. The replacement of routine intraoperative DSA with ICG videoangiography and selective intraoperative DSA in cerebrovascular aneurysm surgery is safe and effective. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Radiation exposure, and procedure and fluoroscopy times in endovascular treatment of intracranial aneurysms: a methodological comparison.

PubMed

Cheung, Nicholas K; Boutchard, Michelle; Carr, Michael W; Froelich, Jens J

2018-01-09

Limited data are available for radiation exposure, and procedure and fluoroscopy times in neuroendovascular treatment (NET) strategies. This study establishes and compares related parameters between coil embolization (COIL), balloon assisted coil embolization (BAC), stent assisted coil embolization (SAC), and flow diverting technology (FDT) in NET of intracranial aneurysms. Between 2010 and 2017, 249 consecutive intracranial aneurysms underwent NET at a single center, all performed by the same operator. Dose area products (DAP), and procedure and fluoroscopy times were recorded and compared between COIL, BAC, SAC, and FDT techniques. Differences in parameters between cohorts were analyzed for significance using the Mann-Whitney U test, unpaired t test and χ 2 test. Additional subgroup analysis was performed for emergency and elective cases. 83 aneurysms were treated with COIL (33%), 72 with BAC (29%), 61 with SAC (25%), and 33 with FDT (13%). Baseline characteristics were largely similar within these groups (P>0.05). Among COIL, BAC, and FDT cohorts, no significant difference was found for mean DAP, or procedure and fluoroscopy times (P>0.05). However, compared with all other cohorts, SAC was associated with a significantly higher DAP and longer procedure and fluoroscopy times (P<0.005). No significant difference was recorded for emergency and elective case subgroups. Compared with other NET strategies, SAC was associated with a significantly higher DAP, and longer procedure and fluoroscopy times. This study provides an initial dataset regarding radiation exposure, and procedure and fluoroscopy times for common NET, and may assist ALARA (As Low As Reasonably Achievable) principles to reduce radiation risks. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Nonsphericity Index and Size Ratio Identify Morphologic Differences between Growing and Stable Aneurysms in a Longitudinal Study of 93 Cases.

PubMed

Chien, A; Xu, M; Yokota, H; Scalzo, F; Morimoto, E; Salamon, N

2018-01-25

Recent studies have strongly associated intracranial aneurysm growth with increased risk of rupture. Identifying aneurysms that are likely to grow would be beneficial to plan more effective monitoring and intervention strategies. Our hypothesis is that for unruptured intracranial aneurysms of similar size, morphologic characteristics differ between aneurysms that continue to grow and those that do not. From aneurysms in our medical center with follow-up imaging dates in 2015, ninety-three intracranial aneurysms (23 growing, 70 stable) were selected. All CTA images for the aneurysm diagnosis and follow-up were collected, a total of 348 3D imaging studies. Aneurysm 3D geometry for each imaging study was reconstructed, and morphologic characteristics, including volume, surface area, nonsphericity index, aspect ratio, and size ratio were calculated. Morphologic characteristics were found to differ between growing and stable groups. For aneurysms of <3 mm, nonsphericity index ( P < .001); 3-5 mm, nonsphericity index ( P < .001); 5-7 mm, size ratio ( P = .003); >7 mm, volume ( P < .001); surface area ( P < .001); and nonsphericity index ( P = .002) were significant. Within the anterior communicating artery, the nonsphericity index ( P = .008) and, within the posterior communicating artery, size ratio ( P = .004) were significant. The nonsphericity index receiver operating characteristic area under the curve was 0.721 for discriminating growing and stable cases on the basis of initial images. Among aneurysms with similar sizes, morphologic characteristics appear to differ between those that are growing and those that are stable. The nonsphericity index, in particular, was found to be higher among growing aneurysms. The size ratio was found to be the second most significant parameter associated with growth. © 2018 by American Journal of Neuroradiology.

The Utility and Benefits of External Lumbar CSF Drainage after Endovascular Coiling on Aneurysmal Subarachnoid Hemorrhage

PubMed Central

Kwon, Ou Young; Kim, Young Jin; Cho, Chun Sung; Lee, Sang Koo; Cho, Maeng Ki

2008-01-01

Objective Cerebral vasospasm still remains a major cause of the morbidity and mortality, despite the developments in treatment of aneurysmal subarachnoid hemorrhage. The authors measured the utility and benefits of external lumbar cerebrospinal fluid (CSF) drainage to prevent the clinical vasospasm and its sequelae after endovascular coiling on aneurysmal subarachnoid hemorrhage in this randomized study. Methods Between January 2004 and March 2006, 280 patients with aneurysmal subarachnoid hemorrhage were treated at our institution. Among them, 107 patients met our study criteria. The treatment group consisted of 47 patients who underwent lumbar CSF drainage during vasospasm risk period (about for 14 days after SAH), whereas the control group consisted of 60 patients who received the management according to conventional protocol without lumbar CSF drainage. We created our new modified Fisher grade on the basis of initial brain computed tomography (CT) scan at admission. The authors established five outcome criteria as follows : 1) clinical vasospasm; 2) GOS score at 1-month to 6-month follow-up; 3) shunt procedures for hydrocephalus; 4) the duration of stay in the ICU and total hospital stay; 5) mortality rate. Results The incidence of clinical vasospasm in the lumbar drain group showed 23.4% compared with 63.3% of individuals in the control group. Moreover, the risk of death in the lumbar drain group showed 2.1% compared with 15% of individuals in the control group. Within individual modified Fisher grade, there were similar favorable results. Also, lumbar drain group had twice more patients than the control group in good GOS score of 5. However, there were no statistical significances in mean hospital stay and shunt procedures between the two groups. IVH was an important factor for delayed hydrocephalus regardless of lumbar drain. Conclusion Lumbar CSF drainage remains to play a prominent role to prevent clinical vasospasm and its sequelae after endovascular coiling on aneurysmal subarachnoid hemorrhage. Also, this technique shows favorable effects on numerous neurological outcomes and prognosis. The results of this study warrant clinical trials after endovascular treatment in patients with aneurysmal SAH. PMID:19096633

Combined Effects of Flow Diverting Strategies and Parent Artery Curvature on Aneurysmal Hemodynamics: A CFD Study

PubMed Central

Yu, Ying; Lv, Nan; Wang, Shengzhang; Karmonik, Christof; Liu, Jian-Min; Huang, Qinghai

2015-01-01

Purpose Flow diverters (FD) are increasingly being considered for treating large or giant wide-neck aneurysms. Clinical outcome is highly variable and depends on the type of aneurysm, the flow diverting device and treatment strategies. The objective of this study was to analyze the effect of different flow diverting strategies together with parent artery curvature variations on altering intra-aneurysmal hemodynamics. Methods Four ideal intracranial aneurysm models with different parent artery curvature were constructed. Computational fluid dynamics (CFD) simulations of the hemodynamics before and after applying five types of flow diverting strategies (single FD, single FD with 5% and 10% packing density of coils, two FDs with 25% and 50% overlapping rate) were performed. Changes in pressure, wall shear stress (WSS), relative residence time (RRT), inflow velocity and inflow volume rate were calculated and compared. Results Each flow diverting strategy resulted in enhancement of RRT and reduction of normalized mean WSS, inflow volume rate and inflow velocity in various levels. Among them, 50% overlapped FD induced most effective hemodynamic changes in RRT and inflow volume rate. The mean pressure only slightly decreased after treatment. Regardless of the kind of implantation of FD, the mean pressure, inflow volume rate and inflow velocity increased and the RRT decreased as the curvature of the parent artery increased. Conclusions Of all flow diverting strategies, overlapping FDs induced most favorable hemodynamic changes. Hemodynamics alterations post treatment were substantially influenced by parent artery curvature. Our results indicate the need of an individualized flow diverting strategy that is tailored for a specific aneurysm. PMID:26398847

An automatic CFD-based flow diverter optimization principle for patient-specific intracranial aneurysms.

PubMed

Janiga, Gábor; Daróczy, László; Berg, Philipp; Thévenin, Dominique; Skalej, Martin; Beuing, Oliver

2015-11-05

The optimal treatment of intracranial aneurysms using flow diverting devices is a fundamental issue for neuroradiologists as well as neurosurgeons. Due to highly irregular manifold aneurysm shapes and locations, the choice of the stent and the patient-specific deployment strategy can be a very difficult decision. To support the therapy planning, a new method is introduced that combines a three-dimensional CFD-based optimization with a realistic deployment of a virtual flow diverting stent for a given aneurysm. To demonstrate the feasibility of this method, it was applied to a patient-specific intracranial giant aneurysm that was successfully treated using a commercial flow diverter. Eight treatment scenarios with different local compressions were considered in a fully automated simulation loop. The impact on the corresponding blood flow behavior was evaluated qualitatively as well as quantitatively, and the optimal configuration for this specific case was identified. The virtual deployment of an uncompressed flow diverter reduced the inflow into the aneurysm by 24.4% compared to the untreated case. Depending on the positioning of the local stent compression below the ostium, blood flow reduction could vary between 27.3% and 33.4%. Therefore, a broad range of potential treatment outcomes was identified, illustrating the variability of a given flow diverter deployment in general. This method represents a proof of concept to automatically identify the optimal treatment for a patient in a virtual study under certain assumptions. Hence, it contributes to the improvement of virtual stenting for intracranial aneurysms and can support physicians during therapy planning in the future. Copyright © 2015 Elsevier Ltd. All rights reserved.

Endovascular minimally invasive treatment of the intracranial aneurysms – first 124 cases

PubMed Central

Dima, S; Scheau, C; Stefanescu, F; Danaila, L

2012-01-01

Introduction: Since May 2005, we have started to treat the intracranial aneurysms endovascular way as an alternative minimally invasive technique to the classic neurosurgery treatment. Objective: Studying the patients’ demographics, clinical presentation, aneurysm size and configuration, type of coils used for embolization, the percentage of compaction and recanalization (especially in patients who presented with subarachnoid hemorrhage), and immediate complications. Methods and Results: An all-inclusive retrospective review of every patient who underwent coils embolization (stent or balloon assisted included) of saccular aneurysms from May 2005 to September 2011 was performed. A total of 116 patients (46 men and 60 women) and 124 aneurysms were treated. A total of 96 patients (41 men and 55 women) underwent follow-up femoral cerebral angiograms (mean follow-up was 25 months and the longest was at 37 months). Five patients required intra-arterial abciximab due to thrombus formation. Four patients had aneurysm rupture while the coil was being advanced. Eleven patients were treated during vasospasm peak. Seven patients had recanalization at 12 months follow-up. Discussion: The average hospitalization period was of 4 days. There is a close relation between Hunt and Hess scale score before treatment and post interventional neurological status. Due to subarachnoid hemorrhage, the vasospasm remains a threat to the patient’s neurological status. The treatment of cerebral aneurysms with endosacular embolization by coils is a safe and durable option. The risk of recanalization or re-rupture in our cohort is small compared to series published elsewhere. Larger series of patients are needed to support our evidence. PMID:23049642

Improving the Efficiency of Abdominal Aortic Aneurysm Wall Stress Computations

PubMed Central

Zelaya, Jaime E.; Goenezen, Sevan; Dargon, Phong T.; Azarbal, Amir-Farzin; Rugonyi, Sandra

2014-01-01

An abdominal aortic aneurysm is a pathological dilation of the abdominal aorta, which carries a high mortality rate if ruptured. The most commonly used surrogate marker of rupture risk is the maximal transverse diameter of the aneurysm. More recent studies suggest that wall stress from models of patient-specific aneurysm geometries extracted, for instance, from computed tomography images may be a more accurate predictor of rupture risk and an important factor in AAA size progression. However, quantification of wall stress is typically computationally intensive and time-consuming, mainly due to the nonlinear mechanical behavior of the abdominal aortic aneurysm walls. These difficulties have limited the potential of computational models in clinical practice. To facilitate computation of wall stresses, we propose to use a linear approach that ensures equilibrium of wall stresses in the aneurysms. This proposed linear model approach is easy to implement and eliminates the burden of nonlinear computations. To assess the accuracy of our proposed approach to compute wall stresses, results from idealized and patient-specific model simulations were compared to those obtained using conventional approaches and to those of a hypothetical, reference abdominal aortic aneurysm model. For the reference model, wall mechanical properties and the initial unloaded and unstressed configuration were assumed to be known, and the resulting wall stresses were used as reference for comparison. Our proposed linear approach accurately approximates wall stresses for varying model geometries and wall material properties. Our findings suggest that the proposed linear approach could be used as an effective, efficient, easy-to-use clinical tool to estimate patient-specific wall stresses. PMID:25007052

Endovascular treatment of bifurcation intracranial aneurysms with the WEB SL/SLS: 6-month clinical and angiographic results

PubMed Central

Bozzetto Ambrosi, Patricia; Sivan-Hoffmann, Rotem; Riva, Roberto; Signorelli, Francesco; Labeyrie, Paul-Emile; Eldesouky, Islam; Sadeh-Gonike, Udi; Armoiry, Xavier; Turjman, Francis

2015-01-01

Background The WEB device is a recent intrasaccular flow disruption technique developed for the treatment of wide-necked intracranial aneurysms. To date, a single report on the WEB Single-Layer (SL) treatment of intracranial aneurysms has been published with 1-months' safety results. The aim of this study is to report our experience and 6-month clinical and angiographic follow-up of endovascular treatment of wide-neck aneurysm with the WEB SL. Methods Ten patients with 10 unruptured wide-necked aneurysms were prospectively enrolled in this study. Feasibility, intraoperative and postoperative complications, and outcomes were recorded. Immediate and 6-month clinical and angiographic results were evaluated. Results Failure of WEB SL placement occurred in two cases. Eight aneurysms were successfully treated using one WEB SL without additional treatment. Three middle cerebral artery, four anterior communicating artery, and one basilar artery aneurysms were treated. Average dome width was 7.5 mm (range 5.4–10.7 mm), and average neck size was 4.9 mm (range 2.6–6.5 mm). No periprocedural complication was observed, and morbi-mortality at discharge and 6 months was 0.0%. Angiographic follow-up at 6 months demonstrated complete aneurysm occlusion in 2/8 aneurysms, neck remnant in 5/8 aneurysms, and aneurysm remnant in 1/8 aneurysm. Conclusions From this preliminary study, treatment of bifurcation intracranial aneurysms using WEB SL is feasible. WEB SL treatment seems safe at 6 months; however, the rate of neck remnants is not negligible due to compression of the WEB SL. Further technical improvements may be needed in order to ameliorate the occlusion in the WEB SL treatment. PMID:26111987

Diabetes may affect intracranial aneurysm stabilization in older patients: Analysis based on intraoperative findings

PubMed Central

Song, Jihye; Shin, Yong Sam

2016-01-01

Background: Only a small proportion of aneurysms progress to rupture. Previous studies have focused on predicting the rupture risk of intracranial aneurysms. Atherosclerotic aneurysm wall appears resistant to rupture. The purpose of this study was to evaluate clinical and morphological factors affecting atherosclerosis of an aneurysm and identify the parameters that predict aneurysm stabilization. Methods: We conducted a retrospective analysis of 253 consecutive patients with 291 unruptured aneurysms who underwent clipping surgery in a single institution between January 2012 and October 2013. Aneurysms were categorized based on intraoperative video findings and assessed morphologic and demographic data. Aneurysms which had the atherosclerotic wall without any super thin and transparent portion were defined as stabilized group and the others as a not-stabilized group. Results: Of the 207 aneurysms, 176 (85.0%) were assigned to the not-stabilized group and 31 (15.0%) to the stabilized group. The relative proportion of stabilized aneurysms increased significantly as the age increased (P < 0.001). Univariate logistic analysis showed that age ≥65 years (P < 0.001), hypertension (P = 0.012), diabetes (P = 0.007), and height ≥3 mm (P = 0.007) were correlated with stabilized aneurysms. Multivariate logistic analysis showed that age ≥65 years (P = 0.009) and hypertension (P = 0.041) were strongly correlated with stable aneurysms. In older patients (≥65 years of age), multivariate logistic regression revealed that only diabetes was associated with stabilized aneurysms (P = 0.027). Conclusions: In patients ≥65 years of age, diabetes mellitus may highly predict the stabilized aneurysms. These results provide useful information in determining treatment and follow-up strategies, especially in older patients. PMID:27313965

Intracranial aneurysms: optimized diagnostic tools call for thorough interdisciplinary treatment strategies.

PubMed

Mueller, Oliver M; Schlamann, Marc; Mueller, Daniela; Sandalcioglu, I Erol; Forsting, Michael; Sure, Ulrich

2011-09-01

Intracranial aneurysms (IAs) require deliberately selected treatment strategies as they are incrementally found prior to rupture and deleterious subarachnoid haemorrhage (SAH). Multiple and recurrent aneurysms necessitate both neurointerventionalists and neurosurgeons to optimize aneurysmal occlusion in an interdisciplinary effort. The present study was conducted to condense essential strategies from a single neurovascular centre with regard to the lessons learned. Medical charts of 321 consecutive patients treated for IAs at our centre from September 2008 until December 2010 were retrospectively analysed for clinical presentation of the aneurysms, multiplicity and treatment pathways. In addition, a selective Medline search was performed. A total of 321 patients with 492 aneurysms underwent occlusion of their symptomatic aneurysm: 132 (41.1%) individuals were treated surgically, 189 (58.2%) interventionally; 138 patients presented with a SAH, of these 44.2% were clipped and 55.8% were coiled. Aneurysms of the middle cerebral artery were primarily occluded surgically (88), whereas most of the aneurysms of the internal carotid artery and anterior communicating artery (114) were treated endovascularly. Multiple aneurysms (range 2-5 aneurysms/individual) were diagnosed in 98 patients (30.2%). During the study period 12 patients with recurrent aneurysms were allocated to another treatment modality (previously clip to coil and vice versa). Our data show that successful interdisciplinary occlusion of IAs is based on both neurosurgical and neurointerventional therapy. In particular, multiple and recurrent aneurysms require tailored individual approaches to aneurysmal occlusion. This is achieved by a consequent interdisciplinary pondering of the optimal strategy to occlude IAs in order to prevent SAH.

Levels of MMP-9 in patients with intracranial aneurysm: Relation with risk factors, size and clinical presentation.

PubMed

Rojas, Hugo Alberto; Fernandes, Karla Simone da Silva; Ottone, Mariana Rodrigues; Magalhães, Kênia Cristina S Fonseca de; Albuquerque, Lucas Alverne Freitas de; Pereira, Julio Leonardo Barbosa; Vieira-Júnior, Gerival; Sousa-Filho, José Lopes; Costa, Bruno Silva; Sandrim, Valéria Cristina; Dellaretti, Marcos; Simões, Renata Toscano

2018-05-01

Intracranial aneurysms are arterial anomalies affecting 2% to 3% of the general population in the world and these ruptures are associated with a high mortality. Some risk factors, such as age, gender, smoking, alcohol, hypertension and familial history are associated with the number of aneurysms and their size. In addition, inflammatory processes within the blood vessels of the brain can activate matrix metalloproteinase-9 (MMP-9), which degrades various components of the extracellular matrix, such as elastin. Thereby, this work has aimed at evaluating the relationship between plasma MMP-9 levels and the risk factors that are associated with intracranial aneurysm, as well as investigating the aneurysm statuses (ruptured and unruptured) and comparing them with the control volunteers. Between August 2014 to June 2016, blood samples were collected from 282 patients (204 ruptured and 78 unruptured saccular intracranial aneurysms) and 286 control volunteers. The MMP-9 plasma levels were measured by ELISA. Statistical analyzes were performed with SPSS software when using parametric or nonparametric tests, after the normality tests. Higher levels of MMP-9 were found in the aneurysm groups as a whole and when they were stratified by rupture status, then compared with the control group (p < 0.0001). When stratifying them by diameter, those smaller than 7 mm presented high levels of MMP-9 (p < 0.0001), especially in the ruptured ones. As for risk factors, hypertension and smoking were the most important. However, hypertension was mostly associated with the ruptured aneurysms (p < 0.0001). High levels of MMP-9 were found in smaller ruptured and unruptured intracranial aneurysms (<7 mm) with strongest statistical associations than other sizes, especially when associated with smoking and hypertension. Copyright © 2018 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Aortic Arch Morphology and Aortic Length in Patients with Dissection, Traumatic, and Aneurysmal Disease.

PubMed

Alberta, H B; Takayama, T; Smits, T C; Wendorff, B B; Cambria, R P; Farber, M A; Jordan, W D; Patel, V; Azizzadeh, A; Rovin, J D; Matsumura, J S

2015-12-01

To assess aortic arch morphology and aortic length in patients with dissection, traumatic injury, and aneurysm undergoing TEVAR, and to identify characteristics specific to different pathologies. This was a retrospective analysis of the aortic arch morphology and aortic length of dissection, traumatic injury, and aneurysmal patients. Computed tomography imaging was evaluated of 210 patients (49 dissection, 99 traumatic injury, 62 aneurysm) enrolled in three trials that received the conformable GORE TAG thoracic endoprosthesis. The mean age of trauma patients was 43 ± 19.6 years, 57 ± 11.7 years for dissection and 72 ± 9.6 years for aneurysm patients. A standardized protocol was used to measure aortic arch diameter, length, and take-off angle and clockface orientation of branch vessels. Differences in arch anatomy and length were assessed using ANOVA and independent t tests. Of the 210 arches evaluated, 22% had arch vessel common trunk configurations. The aortic diameter and the distance from the left main coronary (LMC) to the left common carotid (LCC) were greater in dissection patients than in trauma or aneurysm patients (p < .001). Aortic diameter in aneurysm patients was greater compared with trauma patients (p < .05). The distances from the branch vessels to the celiac artery (CA) were greater in dissection and aneurysm patients than in trauma patients (p < .001). The take-off angle of the innominate (I), LCCA, and left subclavian (LS) were greater, between 19% and 36%, in trauma patients than in dissection and aneurysm patients (p < .001). Clockface orientation of the arch vessels varies between pathologies. Arch anatomy has significant morphologic differences when comparing aortic pathologies. Describing these differences in a large sample of patients is beneficial for device designs and patient selection. Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Lateral supraorbital approach to ipsilateral PCA-P1 and ICA-PCoA aneurysms.

PubMed

Goehre, Felix; Jahromi, Behnam Rezai; Elsharkawy, Ahmed; Lehto, Hanna; Shekhtman, Oleg; Andrade-Barazarte, Hugo; Munoz, Francisco; Hijazy, Ferzat; Makhkamov, Makhkam; Hernesniemi, Juha

2015-01-01

Aneurysms of the posterior cerebral artery (PCA) are rare and often associated with anterior circulation aneurysms. The lateral supraorbital approach allows for a very fast and safe approach to the ipsilateral lesions Circle of Willis. A technical note on the successful clip occlusion of two aneurysms in the anterior and posterior Circle of Willis via this less invasive approach has not been published before. The objective of this technical note is to describe the simultaneous microsurgical clip occlusion of an ipsilateral PCA-P1 and an internal carotid artery - posterior communicating artery (ICA-PCoA) aneurysm via the lateral supraorbital approach. The authors present a technical report of successful clip occlusions of ipsilateral located PCA-P1 and ICA-PCoA aneurysms. A 59-year-old female patient was diagnosed with a PCA-P1 and an ipsilateral ICA-PCoA aneurysm by computed tomography angiography (CTA) after an ischemic stroke secondary to a contralateral ICA dissection. The patient underwent microsurgical clipping after a lateral supraorbital craniotomy. The intraoperative indocyanine green (ICG) videoangiography and the postoperative CTA showed a complete occlusion of both aneurysms; the parent vessels (ICA and PCA) were patent. The patient presents postoperative no new neurologic deficit. The lateral supraorbital approach is suitable for the simultaneous microsurgical treatment of proximal anterior circulation and ipsilateral proximal PCA aneurysms. Compared to endovascular treatment, direct visual control of brainstem perforators is possible.

Impact of Inflow Conditions on Coherent Structures in an Aneurysm

NASA Astrophysics Data System (ADS)

Yu, Paulo; Durgesh, Vibhav; Johari, Hamid

2017-11-01

An aneurysm is an enlargement of a weakened arterial wall that can be debilitating or fatal on rupture. Studies have shown that hemodynamics is integral to developing an understanding of aneurysm formation, growth, and rupture. This investigation focuses on a comprehensive study of the impact of varying inflow conditions and aneurysm shapes on spatial and temporal behavior of flow parameters and structures in an aneurysm. Two different shapes of an idealized rigid aneurysm model were studied and the non-dimensional frequency and Reynolds number were varied between 2-5 and 50-250, respectively. A ViVitro Labs SuperPump system was used to precisely control inflow conditions. Particle Image Velocimetry (PIV) measurements were performed at three different locations inside the aneurysm sac to obtain detailed velocity flow field information. The results of this study showed that aneurysm morphology significantly impacts spatial and temporal behavior of large-scale flow structures as well as wall shear stress distribution. The flow behavior and structures showed a significant difference with change in inflow conditions. A primary fluctuating flow structure was observed for Reynolds number of 50, while for higher Reynolds numbers, primary and secondary flow structures were observed. Furthermore, the paths of these coherent structures were dependent on aneurysm shape and inflow parameters.

Fluid-structure interaction in abdominal aortic aneurysms: Structural and geometrical considerations

NASA Astrophysics Data System (ADS)

Mesri, Yaser; Niazmand, Hamid; Deyranlou, Amin; Sadeghi, Mahmood Reza

2015-08-01

Rupture of the abdominal aortic aneurysm (AAA) is the result of the relatively complex interaction of blood hemodynamics and material behavior of arterial walls. In the present study, the cumulative effects of physiological parameters such as the directional growth, arterial wall properties (isotropy and anisotropy), iliac bifurcation and arterial wall thickness on prediction of wall stress in fully coupled fluid-structure interaction (FSI) analysis of five idealized AAA models have been investigated. In particular, the numerical model considers the heterogeneity of arterial wall and the iliac bifurcation, which allows the study of the geometric asymmetry due to the growth of the aneurysm into different directions. Results demonstrate that the blood pulsatile nature is responsible for emerging a time-dependent recirculation zone inside the aneurysm, which directly affects the stress distribution in aneurismal wall. Therefore, aneurysm deviation from the arterial axis, especially, in the lateral direction increases the wall stress in a relatively nonlinear fashion. Among the models analyzed in this investigation, the anisotropic material model that considers the wall thickness variations, greatly affects the wall stress values, while the stress distributions are less affected as compared to the uniform wall thickness models. In this regard, it is confirmed that wall stress predictions are more influenced by the appropriate structural model than the geometrical considerations such as the level of asymmetry and its curvature, growth direction and its extent.

Perforator and secondary branch origin in relation to the neck of saccular, cerebral bifurcation aneurysms.

PubMed

Pritz, Michael B

2014-11-01

Perforator and secondary branch origin in relation to the neck of cerebral, saccular bifurcation aneurysms were analyzed. These two features were considered important for treatment. From a series of microsurgically clipped saccular cerebral aneurysms, 142 bifurcation aneurysms had detailed imaging studies and operative records that could be analyzed. The incidence of perforator origin from the aneurysm neck was as follows: basilar, 1/15 (7%); internal carotid artery bifurcation, 4/23 (17%); main stem of the middle cerebral artery/secondary branch of the middle cerebral artery, 6/52 (12%); anterior communicating artery region, 5/46 (11%); and distal bifurcation vessels, 0/6 (0%). Aneurysms arising from the anterior communicating artery between the anterior cerebral arteries had a high incidence of perforator origin from the aneurysm neck. The location of secondary branch origin from the aneurysm neck varied depending on the aneurysm group. Perforator origin from the aneurysm neck was infrequent. A subgroup of anterior communicating artery region aneurysms had a high incidence of perforator origin from the aneurysm neck. Although protection of these neck perforators will be difficult, their identification may be even more challenging. Secondary branch origin from the aneurysm neck varied depending on the aneurysm group. Advanced endovascular techniques are needed to obliterate aneurysms in which the secondary branch(es) arise from the aneurysm neck. If this is not possible, craniotomy and clip ligation will be required if complete aneurysm obliteration is the goal. Copyright © 2014 Elsevier Inc. All rights reserved.

Giant intracranial aneurysm embolization with a yield stress fluid material: insights from CFD analysis.

PubMed

Wang, Weixiong; Graziano, Francesca; Russo, Vittorio; Ulm, Arthur J; De Kee, Daniel; Khismatullin, Damir B

2013-01-01

The endovascular treatment of intracranial aneurysms remains a challenge, especially when the aneurysm is large in size and has irregular, non-spherical geometry. In this paper, we use computational fluid dynamics to simulate blood flow in a vertebro-basilar junction giant aneurysm for the following three cases: (1) an empty aneurysm, (2) an aneurysm filled with platinum coils, and (3) an aneurysm filled with a yield stress fluid material. In the computational model, blood and the coil-filled region are treated as a non-Newtonian fluid and an isotropic porous medium, respectively. The results show that yield stress fluids can be used for aneurysm embolization provided the yield stress value is 20 Pa or higher. Specifically, flow recirculation in the aneurysm and the size of the inflow jet impingement zone on the aneurysm wall are substantially reduced by yield stress fluid treatment. Overall, this study opens up the possibility of using yield stress fluids for effective embolization of large-volume intracranial aneurysms.

Intrathecal application of the nimodipine slow-release microparticle system eg-1962 for prevention of delayed cerebral ischemia and improvement of outcome after aneurysmal subarachnoid hemorrhage.

PubMed

Etminan, Nima; Macdonald, R Loch; Davis, Cara; Burton, Kevin; Steiger, Hans-Jakob; Hänggi, Daniel

2015-01-01

The effective reduction of delayed cerebral ischemia (DCI), a main contributor for poor outcome following aneurysmal subarachnoid hemorrhage (SAH), remains challenging. Previous clinical trials on systemic pharmaceutical treatment of SAH mostly failed to improve outcome, probably because of insensitive pharmaceutical targets and outcome measures, small sample size, insufficient subarachnoid drug concentrations and also detrimental, systemic effects of the experimental treatment per se. Interestingly, in studies that are more recent, intrathecal administration of nicardipine pellets following surgical aneurysm repair was suggested to have a beneficial effect on DCI and neurological outcome. However, this positive effect remained restricted to patients who were treated surgically for a ruptured aneurysm. Because of the favorable results of the preclinical data on DCI and neurological outcome in the absence of neurotoxicity or systemic side effects, we are initiating clinical trials. The PROMISE (Prolonged Release nimOdipine MIcro particles after Subarachnoid hemorrhage) trial is designed as an unblinded, nonrandomized, single-center, single-dose, dose-escalation safety and tolerability phase 1 study in patients surgically treated for aSAH and will investigate the effect of intracisternal EG-1962 administration. The NEWTON (Nimodipine microparticles to Enhance recovery While reducing TOxicity after subarachNoid hemorrhage) trial is a phase 1/2a multicenter, controlled, randomized, open-label, dose-escalation, safety, tolerability, and pharmacokinetic study comparing EG-1962 and nimodipine in patients with aneurysmal SAH.

Mechanical deterioration underlies malignant behavior of aneurysmal human ascending aorta.

PubMed

Koullias, George; Modak, Raj; Tranquilli, Maryann; Korkolis, Dimitris P; Barash, Paul; Elefteriades, John A

2005-09-01

The human ascending aorta becomes markedly prone to rupture and dissection at a diameter of 6 cm. The mechanical substrate for this malignant behavior is unknown. This investigation applied engineering analysis to human ascending aortic aneurysms and compared their structural characteristics with those of normal aortas. We measured the mechanical characteristics of the aorta by direct epiaortic echocardiography at the time of surgery in 33 patients with ascending aortic aneurysm undergoing aortic replacement and in 20 control patients with normal aortas undergoing coronary artery bypass grafting. Six parameters were measured in all patients: aortic diameter in systole and diastole, aortic wall thickness in systole and diastole, and blood pressure in systole and diastole. These were used to calculate mechanical characteristics of the aorta from standard equations. Aortic distensibility reflects the elastic qualities of the aorta. Aortic wall stress reflects the disrupting force experienced within the aortic wall. Incremental elastic modulus indicates loss of elasticity reserve. Aortic distensibility falls to extremely low levels as aortic dimension rises toward 6 cm (3.02 mm Hg(-1) for small aortas versus 1.45 mm Hg(-1) for aortas larger than 5 cm, P < .05). Aortic wall stress rises to 157.8 kPa for the aneurysmal aorta, compared with 92.5 kPa for normal aortas. For 6-cm aortas at pressures of 200 mm Hg or more, wall stress rises to 857 kPa, nearly exceeding the known maximal tensile strength of human aneurysmal aortic wall. Incremental elastic modulus deteriorates (1.93 +/- 0.88 MPa vs 1.18 +/- 0.21 MPa, P < .05) in aneurysmal aortas relative to that in normal aortas. The mechanical properties of the aneurysmal aorta deteriorate dramatically as the aorta enlarges, reaching critical levels associated with rupture by a diameter of 6 cm. This mechanical deterioration provides an explanation in engineering terms for the malignant clinical behavior (rupture and dissection) of the aorta at these dimensions. This work adds to our fundamental understanding of the biology of aortic aneurysms and promises to permit future application of engineering measurements to supplement aneurysm size in clinical decision making in aneurysmal disease.

Prevalence of Incidental Clinoid Segment Saccular Aneurysms.

PubMed

Revilla-Pacheco, Francisco; Escalante-Seyffert, María Cecilia; Herrada-Pineda, Tenoch; Manrique-Guzman, Salvador; Perez-Zuniga, Irma; Rangel-Suarez, Sergio; Rubalcava-Ortega, Johnatan; Loyo-Varela, Mauro

2018-04-12

Clinoid segment aneurysms are cerebral vascular lesions recently described in the neurosurgical literature. They arise from the clinoid segment of the internal carotid artery, which is the segment limited rostrally by the dural carotid ring and caudally, by the carotid-oculomotor membrane. Even although clinoid segment aneurysms represent a common incidental finding in magnetic resonance studies, its prevalence has not been yet reported. To determine the prevalence of incidental clinoid segment saccular aneurysms diagnosed by magnetic resonance imaging as well as their anatomic architecture and their association with smoking, arterial hypertension, age, and sex of patients. A total of 500 patients were prospectively studied with magnetic resonance imaging time-of-flight sequence and angioresonance with contrast material, to search for incidental saccular intracranial aneurysms. The site of primary interest was the clinoid segment, but the presence of aneurysms in any other location was determined for comparison. The relation among the presence of clinoid segment aneurysms, demographic factors, and secondary diagnosis of arterial hypertension, smoking, and other vascular/neoplastic cerebral lesions was analyzed. We found a global prevalence of incidental aneurysms of 7% (95% confidence interval, 5-9), with a prevalence of clinoid segment aneurysms of 3% (95% confidence interval, 2-4). Univariate logistic regression analysis showed a statistically significant relationship among incidental aneurysms, systemic arterial hypertension (P = 0.000), and smoking (P = 0.004). In the studied population, incidental clinoid segment aneurysms constitute the variety with highest prevalence. Copyright © 2018 Elsevier Inc. All rights reserved.

Hybrid repair of right aortic arch aneurysm with a Kommerell's diverticulum.

PubMed

Tanaka, Koyu; Yoshitaka, Hidenori; Chikazawa, Genta; Sakaguchi, Taichi; Totsugawa, Toshinori; Tamura, Kentaro

2014-07-01

We describe the case of a 74-year-old man who underwent a hybrid open and endovascular approach for repair of dissecting thoracic aortic aneurysm of a right aortic arch with aberrant left subclavian artery arising from a Kommerell's diverticulum. Total debranching using a tailored quadrifurcated graft and thoracic endovascular aneurysm repair for the transverse aortic lesion were performed. The procedures were successfully accomplished with complete exclusion of the aneurysm. This hybrid procedure for complex aortic arch disease may reduce perioperative complications compared to challenging conventional open approaches. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Estimation of aneurysm wall stresses created by treatment with a shape memory polymer foam device

PubMed Central

Hwang, Wonjun; Volk, Brent L.; Akberali, Farida; Singhal, Pooja; Criscione, John C.

2012-01-01

In this study, compliant latex thin-walled aneurysm models are fabricated to investigate the effects of expansion of shape memory polymer foam. A simplified cylindrical model is selected for the in-vitro aneurysm, which is a simplification of a real, saccular aneurysm. The studies are performed by crimping shape memory polymer foams, originally 6 and 8 mm in diameter, and monitoring the resulting deformation when deployed into 4-mm-diameter thin-walled latex tubes. The deformations of the latex tubes are used as inputs to physical, analytical, and computational models to estimate the circumferential stresses. Using the results of the stress analysis in the latex aneurysm model, a computational model of the human aneurysm is developed by changing the geometry and material properties. The model is then used to predict the stresses that would develop in a human aneurysm. The experimental, simulation, and analytical results suggest that shape memory polymer foams have potential of being a safe treatment for intracranial saccular aneurysms. In particular, this work suggests oversized shape memory foams may be used to better fill the entire aneurysm cavity while generating stresses below the aneurysm wall breaking stresses. PMID:21901546

Stent-assisted coil embolization of aneurysms with small parent vessels: safety and efficacy analysis.

PubMed

Kühn, Anna Luisa; Hou, Samuel Y; Puri, Ajit S; Silva, Christine F; Gounis, Matthew J; Wakhloo, Ajay K

2016-06-01

Stent-assisted coil embolization (SACE) is a viable therapeutic approach for wide-neck intracranial aneurysms. However, it can be technically challenging in small cerebral vessels (≤2 mm). To present our experience with stents approved for SACE in aneurysms with small parent arteries. All patients who underwent stent-assisted aneurysm treatment with either a Neuroform or an Enterprise stent device at our institution between June 2006 and October 2012 were identified. Additionally, we evaluated each patient's vascular risk factors, aneurysm characteristics (ruptured vs non-ruptured, incidental finding, recanalized) and follow-up angiography data. A total of 41 patients with 44 aneurysms met our criteria, including 31 women and 10 men. Most of the aneurysms were located in the anterior circulation (75%). Stent placement in vessels 1.2-2 mm in diameter was successful in 93.2%. Thromboembolic complications occurred in 6 cases and vessel straightening was seen in 1 case only. Initial nearly complete to complete aneurysm obliteration was achieved in 88.6%. Six-month follow-up angiography showed coil compaction in three cases, one asymptomatic in-stent stenosis and stent occlusion. Twelve to 20-months' follow-up showed stable coil compaction in two patients compared with previous follow-up, and aneurysm recanalization in two patients. Twenty-four to 36-months' follow-up showed further coil compaction in one of these patients and aneurysm recanalization in a previous case of stable coil compaction on mid-term follow-up. Our results suggest that SACE of aneurysms with small parent vessels is feasible in selected cases and shows good long-term patency rates of parent arteries. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

A Critical Analysis of the Utility of Intraoperative Angiography.

PubMed

Ares, William J; Kenmuir, Cynthia L; Panczykowski, David M; Weiner, Gregory M; Jadhav, Ashu P; Jovin, Tudor G; Gross, Bradley A; Jankowitz, Brian T

2018-02-01

Intraoperative digital subtraction angiography (ioDSA) is touted as the gold standard imaging evaluation for aneurysm clip constructs. Candid evaluations of its limitations are sparse. A prospectively collected hospital billing database was queried to identify craniotomies for aneurysm clipping from January 2010 to December 2013. We evaluated the rate of occult residual and parent vessel stenosis determined on follow-up angiography for patients undergoing ioDSA and those not undergoing ioDSA. Comparisons were performed via Fisher exact test, with P < 0.05 considered statistically significant. From our database search, we found 187 patients who underwent ioDSA after aneurysm clipping and an additional 91 patients who did not. Results from ioDSA influenced operative management in 17% of cases. Sixty-four patients with 70 treated aneurysms undergoing ioDSA had postoperative angiography; 7 occult residuals were discovered, yielding a 10% false-negative rate, with 10% of aneurysms showing residual. Occult residuals at the middle cerebral artery bifurcation represented most discovered residuals (6/7). Thirty-two patients with 37 treated aneurysms did not undergo ioDSA and had angiographic follow-up; 24% of patients were found to have residual aneurysms (P = 0.08 compared with patients undergoing ioDSA). Residuals at the anterior communicating artery (ACoA) represented 56% of all residuals, whereas the ACoA represented only 18% of aneurysms clipped. The rate of residuals was significantly higher than that for patients with clipped ACoA aneurysms undergoing ioDSA (P = 0.008). ioDSA influenced management in nearly one fifth of cases. It can be particularly beneficial in detecting residuals for ACoA aneurysms; its benefit was less apparent for middle cerebral artery aneurysms. Copyright © 2017 Elsevier Inc. All rights reserved.

Intrinsic, Transitional, and Extrinsic Morphological Factors Associated With Rupture of Intracranial Aneurysms.

PubMed

Ho, Allen L; Lin, Ning; Frerichs, Kai U; Du, Rose

2015-09-01

As diagnosis and treatment of unruptured intracranial aneurysms continues to increase, management principles remain largely based on size. This is despite mounting evidence that aneurysm location and other morphologic variables could play a role in predicting overall risk of rupture. Morphological parameters can be divided into 3 main groups, those that are intrinsic to the aneurysm, those that are extrinsic to the aneurysm, and those that involve both the aneurysm and surrounding vasculature (transitional). We present an evaluation of intrinsic, transitional, and extrinsic factors and their association with ruptured aneurysms. Using preoperative computed tomographic angiography, we generated 3-dimensional models of aneurysms and their surrounding vasculature with Slicer software. Using univariate and multivariate analyses, we examined the association of intrinsic, transitional, and extrinsic aspects of aneurysm morphology with rupture. Between 2005 and 2013, 227 cerebral aneurysms in 4 locations were evaluated/treated at a single institution, and computed tomographic angiographies of 218 patients (97 unruptured and 130 ruptured) were analyzed. Ruptured aneurysms analyzed were associated with clinical factors of absence of multiple aneurysms and history of no prior rupture, and morphologic factors of greater aspect ratio. On multivariate analysis, aneurysm rupture remained associated with history of no prior rupture, greater flow angle, greater daughter-daughter vessel angle, and smaller parent-daughter vessel angle. By studying the morphology of aneurysms and their surrounding vasculature, we identified several parameters associated with ruptured aneurysms that include intrinsic, transitional, and extrinsic factors of cerebral aneurysms and their surrounding vasculature.

Pipeline embolization device versus coiling for the treatment of large and giant unruptured intracranial aneurysms: a cost-effectiveness analysis.

PubMed

Wali, Arvin R; Park, Charlie C; Santiago-Dieppa, David R; Vaida, Florin; Murphy, James D; Khalessi, Alexander A

2017-06-01

OBJECTIVE Rupture of large or giant intracranial aneurysms leads to significant morbidity, mortality, and health care costs. Both coiling and the Pipeline embolization device (PED) have been shown to be safe and clinically effective for the treatment of unruptured large and giant intracranial aneurysms; however, the relative cost-to-outcome ratio is unknown. The authors present the first cost-effectiveness analysis to compare the economic impact of the PED compared with coiling or no treatment for the endovascular management of large or giant intracranial aneurysms. METHODS A Markov model was constructed to simulate a 60-year-old woman with a large or giant intracranial aneurysm considering a PED, endovascular coiling, or no treatment in terms of neurological outcome, angiographic outcome, retreatment rates, procedural and rehabilitation costs, and rupture rates. Transition probabilities were derived from prior literature reporting outcomes and costs of PED, coiling, and no treatment for the management of aneurysms. Cost-effectiveness was defined, with the incremental cost-effectiveness ratios (ICERs) defined as difference in costs divided by the difference in quality-adjusted life years (QALYs). The ICERs < $50,000/QALY gained were considered cost-effective. To study parameter uncertainty, 1-way, 2-way, and probabilistic sensitivity analyses were performed. RESULTS The base-case model demonstrated lifetime QALYs of 12.72 for patients in the PED cohort, 12.89 for the endovascular coiling cohort, and 9.7 for patients in the no-treatment cohort. Lifetime rehabilitation and treatment costs were $59,837.52 for PED; $79,025.42 for endovascular coiling; and $193,531.29 in the no-treatment cohort. Patients who did not undergo elective treatment were subject to increased rates of aneurysm rupture and high treatment and rehabilitation costs. One-way sensitivity analysis demonstrated that the model was most sensitive to assumptions about the costs and mortality risks for PED and coiling. Probabilistic sampling demonstrated that PED was the cost-effective strategy in 58.4% of iterations, coiling was the cost-effective strategy in 41.4% of iterations, and the no-treatment option was the cost-effective strategy in only 0.2% of iterations. CONCLUSIONS The authors' cost-effective model demonstrated that elective endovascular techniques such as PED and endovascular coiling are cost-effective strategies for improving health outcomes and lifetime quality of life measures in patients with large or giant unruptured intracranial aneurysm.

Volumetric PIV in Patient-Specific Cerebral Aneurysm

NASA Astrophysics Data System (ADS)

Brindise, Melissa; Dickerhoff, Ben; Saloner, David; Rayz, Vitaliy; Vlachos, Pavlos

2016-11-01

Cerebral aneurysms impose a unique challenge in which neurosurgeons must assess and decide between the risk of rupture and risk of treatment for each patient. Risk of rupture is often difficult to determine and most commonly assessed using geometric data including the size and shape of the aneurysm and parent vessel. Hemodynamics is thought to play a major role in the growth and rupture of a cerebral aneurysm, but its specific influence is largely unknown due to the inability of in vivo modalities to characterize detailed flow fields and limited in vitro studies. In this work, we use a patient-specific basilar tip aneurysm model and volumetric particle image velocimetry (PIV). In vivo, 4-D PC-MRI measurements were obtained for this aneurysm and the extracted pulsatile waveform was used for the in vitro study. Clinically relevant metrics including wall shear stress (WSS), oscillatory shear index (OSI), relative residence time (RRT), 3-D pressure contours, and pressure wave speed were subsequently computed. This is the first study to investigate in vitro 3-D pressure fields within a cerebral aneurysm. The results of this study demonstrate how these metrics influence the biomechanics of the aneurysm and ultimately their affect on the risk of rupture.

Increased Prevalence of Cerebrovascular Disease in Hospitalized Patients with Ehlers-Danlos Syndrome.

PubMed

Kim, Sarasa T; Cloft, Harry; Flemming, Kelly D; Kallmes, David F; Lanzino, Giuseppe; Brinjikji, Waleed

2017-08-01

Small studies have suggested that Ehlers-Danlos syndrome (EDS) is associated with a number of cerebrovascular complications. We sought to determine whether a clinical diagnosis of EDS is associated with a higher prevalence of cerebrovascular diseases than the general population by performing a case-control study of hospitalized patients in the Nationwide Inpatient Sample (NIS). Using the 2000-2012 NIS, we performed a case-control study matching cases of EDS to controls without such a diagnosis. The prevalence of various cerebrovascular diseases between the 2 groups was compared, and multivariate logistic regression was used to adjust for suspected comorbidities. Between 2000 and 2012, there were a total of 9067 discharges carrying a diagnosis of EDS. On univariate analysis, patients with EDS were more likely to be hospitalized for carotid dissection (.2% versus .01%, odds ratio [OR] = 18.0, confidence interval [CI] = 2.41-135.12, P < .0001), vertebral dissection (.1% versus 0%, P = .008), cervical artery aneurysm (.1% versus .01%, OR = 9.01, CI = 1.14-71.11, P < .0001), cerebral aneurysm (.4% versus .09%, OR = 4.89, CI = 2.28-10.47, P < .0001), and cerebrovascular malformation (.1% versus .02%, OR = 5, CI = 1.10-22.85, P = .021), compared to the controls. On multivariate analysis adjusted for age, race, and comorbidities, EDS patients had significantly higher odds of carotid dissection (OR = 15.02, CI = 3.08-270.87, P < .0001), vertebral dissection (OR = 2406539.5, P = .0037), cervical artery aneurysm (OR = 11.75, CI = 2.11-220.71, P = .0026), cerebral aneurysm (OR = 5.59, CI = 2.69-13.18, P < .0001), and cerebrovascular malformation (OR = 4.67, CI = 1.20-30.87, P = .0243). Carotid and vertebral dissections, cervical and cerebral aneurysms, as well as other cerebrovascular malformations are more common in hospitalized patients with EDS compared to controls. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Treatment Strategies for Intracranial Mirror Aneurysms.

PubMed

Wang, Wen-Xin; Xue, Zhe; Li, Lin; Wu, Chen; Zhang, Yan-Yang; Lou, Xin; Ma, Lin; Sun, Zheng-Hui

2017-04-01

Intracranial mirror aneurysms are clinically rare and uncommonly reported in the literature. Therefore, the present study evaluated a series of mirror aneurysm cases with respect to the clinical features of the patients and the treatment strategies that were used. This study retrospectively reviewed and systematically analyzed the clinical features, imaging data, treatment methods, and treatment outcomes of 68 cases of mirror aneurysms (a total of 70 pairs) in patients who were admitted to our department between November 2007 and May 2016. The patient population included 24 male and 44 female patients, with a mean age of 52 years. The mirror aneurysms were primarily located in posterior communicating artery and middle cerebral artery and 65 of the aneurysms were large or giant (≧10 mm). Of the 68 patients, 28 were treated by the clipping or embolization of all aneurysms in one stage, 16 were treated in 2 stages, 16 were treated by treating part of the aneurysms, and 8 were observed. The modified Rankin Scale scores of the 60 patients that were treated indicated that 52 had a good recovery (modified Rankin Scale score ≦2; 86.7%), and 1 patient died. Treatment strategies for mirror aneurysms should be determined individually according to the location, size, and morphology of the aneurysm, as well as the clinical manifestations of each patient. Furthermore, the responsible ruptured aneurysm should be given treatment priority, whereas the contralateral unruptured aneurysm should be observed or treated in either 1 or 2 stages. Copyright © 2017 Elsevier Inc. All rights reserved.

The association between lunar phase and intracranial aneurysm rupture: Myth or reality? Own data and systematic review.

PubMed

Bunevicius, Adomas; Gendvilaite, Agne; Deltuva, Vytenis Pranas; Tamasauskas, Arimantas

2017-05-19

It is a common belief in medical community that lunar phases have an impact on human health. A growing body of evidence indicates that lunar phases can predict the risk to develop acute neurological and vascular disorders. The goal of present report was to present our institution data and to perform systematic review of studies examining the association of intracranial aneurysm rupture with moon phases. We identified all patients admitted to our department for ruptured intracranial aneurysms in a period between November, 2011 and December, 2014. Patients with a known aneurysm rupture date were included. Lunar phases were determined by dividing lunar month (29.5 days) into eight equal parts, i.e., new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last quarter and waning crescent. A systematic literature review was undertaken to identify studies that evaluated the association of lunar phases with the incident of intracranial aneurysm rupture. One hundred and eighty-six patients (62 men and 124 women, median age 56 years) were admitted to our department for treatment of ruptured intracranial aneurysms. The rate of intracranial aneurysm rupture was equally distributed across all phases of the lunar cycle (X 2 [7; 185] = 12.280, p = 0.092). We identified three studies that evaluated the association between incident intracranial aneurysm rupture and lunar phases with a total of 1483 patients. One study from Lebanon found that the incidence rate of intracranial aneurysm rupture was statistically significantly greater during the new moon phase (25% cases), relative to the other seven lunar phases (p < 0.001). Two subsequent studies from Austria and Germany in larger patient samples (n = 717 and n = 655, respectively) did not find an association between lunar phases and intracranial aneurysm rupture (p-values of 0.84 and 0.97, respectively). When analyzing all four studies together, we did not find an association between lunar phases and incidence of intracranial aneurysm rupture (X 2 [1668; 7] = 2.080, p = 0.955). Moon phases are not associated with incidence of intracranial aneurysm rupture. Studies investigating the association of intracranial aneurysm rupture with lunar illumination defined using more sensitive approaches are encouraged.

Evolution of Management of Intracranial Aneurysms in Children: A Systematic Review of the Modern Literature.

PubMed

Beez, Thomas; Steiger, Hans-Jakob; Hänggi, Daniel

2016-05-01

Pediatric intracranial aneurysms are rare. Management of their more common adult counterparts was profoundly influenced by recent high-quality clinical studies. The aim of this review was to aggregate the modern pediatric data published in the wake of these studies and to analyze their impact on management of aneurysms in children. A systematic PubMed search identified 135 publications published between 2000 and 2015, accounting for 573 children and 656 aneurysms. Descriptive statistical analyses revealed differences between children and adults concerning demographics and aneurysm characteristics. A significant proportion of patients were treated endovascularly, suggesting endovascular treatment has been established in the therapeutic armamentarium for pediatric aneurysms. However, these data highlight the unique nature of pediatric aneurysms, and neither this review nor generalization from adult data can replace high-quality clinical research. Multicenter registries and controlled trials are required to establish the natural history and evidence-based treatment of pediatric aneurysms. © The Author(s) 2015.

Mortality outcomes of ruptured abdominal aortic aneurysms and rural presentation.

PubMed

Munday, Emily; Walker, Stuart

2016-10-01

Centralisation of vascular surgery services has coincided with a move towards endovascular repair of ruptured abdominal aortic aneurysms with the goal to improve patient outcomes. The aim of this study was to assess the effect of rural presentation and transfer times on survival from ruptured abdominal aortic aneurysm. A retrospective review. All patients presenting with ruptured abdominal aortic aneurysm to public hospitals in Tasmania between July 2006 and April 2013. Demographic data, Glasgow aneurysm score, Hardman index, transfer times, operative technique and 30-day mortality were collected from medical records. Over the study period 127 patients presented to public hospitals in Tasmania with ruptured abdominal aortic aneurysm. A total of 27 presented to north west hospitals where no vascular surgery service is provided (NWRH), 23 to a northern hospital where an intermittent vascular surgery service is provided (LGH) and 77 to the state tertiary vascular surgery service (RHH). Of these, 4 (14.8%) died at NWRH, 6 (26.1%) died at LGH and 43 (55.8%) died at RHH without operation. Of the 35 patients transferred from NWRH and LGH to RHH, 5 died without operation. Median time from presentation to theatre at RHH if transferred from NWRH was 6.25 hours, from the LGH 4.75 hours, compared to 2.75 hours when presenting directly to RHH. Open repair was performed in 41 patients and endovascular repair in 23 patients. Overall 30-day mortality in those treated at RHH was 26.6% (39.0% for open repair, 4.3% for endovascular repair). Mortality for intended operative patients initially presenting to non-RHH hospitals was 33.3% vs. 32.3% for those initially presenting to RHH. p Value 0.93. There was no clinical or statistical disadvantage to rural presentation and transfer for patients presenting with ruptured abdominal aortic aneurysm in Tasmania. Endovascular repair has a role despite long transfer times. © The Author(s) 2015.

Long-term follow-up analysis of microsurgical clip ligation and endovascular coil embolization for dorsal wall blister aneurysms of the internal carotid artery.

PubMed

Brown, Mason A; Guandique, Cristian F; Parish, Jonathan; McMillan, Aubrey C; Lehnert, Stephen; Mansour, Nassir; Tu, Michael; Bohnstedt, Bradley N; Payner, Troy D; Leipzig, Thomas J; DeNardo, Andrew J; Scott, John A; Cohen-Gadol, Aaron A

2017-05-01

Blister aneurysms at non-branching sites of the dorsal internal carotid artery (dICA) are fragile, rare, and often difficult to treat. The purpose of this study is to address the demographics, treatment modalities, and long-term outcome of patients treated for dICA blister aneurysms. A retrospective review of medical records identified all consecutive patients who presented with a blister aneurysm from 2002 to 2011 at our institution. Eighteen patients (M=7, F=11; mean age: 48.4±15.1years; range: 15-65years) harbored a total of 43 aneurysms, 25 of which were dorsal wall blister aneurysms of the ICA. Eleven (61.1%) patients presented with aneurysmal subarachnoid hemorrhage (aSAH), and 10 (55.6%) patients had multiple aneurysms at admission. Twelve patients had 18 aneurysms that were treated microsurgically. Five (41.7%) of these patients had a single recurrence that was retreated with subsequent repeat clip ligation. Six patients had 7 blister aneurysms that were treated with endovascularly. One (16.7%) of these patients had a single recurrence that was retreated with subsequent coil embolization. Postoperative vasospasm occurred in 8 (44.4%) patients, one of whom suffered from a stroke. This is one of the largest single-institution dICA blister aneurysm studies to date. There was no detected significant difference between microsurgical clip ligation and endovascular coil embolization in terms of surgical outcome. These blister aneurysms demonstrate a propensity to be associated with multiple cerebral aneurysms. Strict clinical and angiographic long-term follow-up may be warranted. Blister aneurysms are focal wall defects covered by a thin layer of fibrous tissue and adventitia, lacking the usual collagenous layer. Due to their pathologically thin vessel wall, blister aneurysms are prone to rupture. The management of these rare and fragile aneurysms presents a number of challenges. Here, we address the long-term outcome of patients treated for blister aneurysms at non-branching sites of the dICA. The presented data and analysis is imperative to determine the necessary strict long-term clinical and angiographic follow-up. Copyright © 2017 Elsevier Ltd. All rights reserved.

High prevalence of intracranial aneurysms in patients with aortic dissection or aneurysm: feasibility of extended aorta CT angiography with involvement of intracranial arteries.

PubMed

Lee, Dahye; Ahn, Sung Jun; Cho, Eun-Suk; Kim, Yong Bae; Song, Suk-Won; Jung, Woo Sang; Suh, Sang Hyun

2017-10-01

Previous studies have suggested a higher prevalence of intracranial aneurysms (IAs) in patients with aortic aneurysms (AAs). To carry out a preliminary study to evaluate the prevalence of IAs in these patients and the diagnostic feasibility of extended aorta CT angiography (CTA), including intracranial arteries as well as the aorta. We retrospectively reviewed all patients with a clinical diagnosis of AA or aortic dissection (AD) who had undergone aorta CTA as well as MR angiography, CTA, and/or DSA of the brain between 2009 and 2014. Since 2012, the extended aorta CTA protocol has been applied in these patients. Characteristics of IAs were classified with baseline clinical data. For quantitative and qualitative assessment by two independent raters, brain images obtained by extended aorta CTA and brain CTA were compared. The radiation dose of the two aorta protocols was compared. The prevalence of IA was 22.2% (35/158). All IAs were detected by extended aorta CTA, except one small aneurysm (<3 mm). The mean vascular attenuation value between brain images showed no difference (p=0.83), but the contrast-to-noise ratio was significantly lower in extended aorta CTA (p<0.001). In qualitative assessment, the interobserver agreement was substantial (k=0.79). For the radiation dose, the dose-length product of the extended aorta CTA increased with increment of the scan range (p=0.048). With a high prevalence of IAs in patients with ADs or AAs, extended aorta CTA could be used to evaluate aorta disease and IA in a single session. However, further prospective studies are needed to prove efficacy and safety of the extended aorta CTA protocol in patients with AAs or ADs. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Fluid-structure interaction of patient-specific Circle of Willis with aneurysm: Investigation of hemodynamic parameters.

PubMed

Jahed, Mahsa; Ghalichi, Farzan; Farhoudi, Mehdi

2018-01-01

Circle of Willis (COW) is a network of cerebral artery which continually supplies the brain with blood. Any disturbance in this supply will result in trauma or even death. One of these damages is known as brain Aneurysm. Clinical methods for diagnosing aneurysm can only measure blood velocity; while, in order to understand the causes of these occurrences it is necessary to have information about the amount of pressure and wall shear stress, which is possible through computational models. In this study purpose is achieving exact information of hemodynamic blood flow in COW with an aneurysm and investigation of effective factors on growth and rupture of aneurysm. Here, realistic three-dimensional models have been produced from angiography images. Considering fluid-structure interaction have been simulated by the ANSYS.CFX software. Hemodynamic Studying of the COW and intra-aneurysm showed that the WSS and wall tension in the neck of aneurysms for case A are 129.5 Pa, and 12.2 kPa and for case B they are 53.3 Pa and 56.2 kPa, and more than their fundus, thus neck of aneurysm is prone to rupture. This study showed that the distribution of parameters was dependent on the geometry of the COW, and maximum values are seen in areas prone to aneurysm formation.

Atmospheric Pressure Variation is a Delayed Trigger for Aneurysmal Subarachnoid Hemorrhage.

PubMed

van Donkelaar, Carlina E; Potgieser, Adriaan R E; Groen, Henk; Foumani, Mahrouz; Abdulrahman, Herrer; Sluijter, Rob; van Dijk, J Marc C; Groen, Rob J M

2018-04-01

There is an ongoing search for conditions that induce spontaneous subarachnoid hemorrhage (SAH). The seasonal pattern of SAH is shown in a large meta-analysis of the literature, but its explanation remains undecided. There is a clear need for sound meteorologic data to further elucidate the seasonal influence on SAH. Because of the stable and densely monitored atmospheric situation in the north of the Netherlands, we reviewed our unique cohort on the seasonal incidence of SAH and the association between SAH and local atmospheric changes. Our observational cohort study included 1535 patients with spontaneous SAH admitted to our neurovascular center in the north of the Netherlands between 2000 and 2015. Meteorologic data could be linked to the day of the ictus. To compare SAH incidences over the year and to test the association with meteorologic conditions, incidence rate ratios (IRRs) with corresponding 95% confidence intervals (CIs) were used, calculated by Poisson regression analyses. Atmospheric pressure variations were significantly associated with aneurysmal SAH. In particular, the pressure change on the second and third day before the ictus was independently correlated to a higher incidence of aneurysmal SAH (IRR, 1.11; 95% CI, 1.00-1.23). The IRR for aneurysmal SAH in July was calculated 0.67 (95% CI, 0.49-0.92) after adjustment for temperature and atmospheric pressure changes. Atmospheric pressure variations are a delayed trigger for aneurysmal SAH. Also, a significantly decreased incidence of aneurysmal SAH was noted in July. Copyright © 2018 Elsevier Inc. All rights reserved.

Microembolism after Endovascular Treatment of Unruptured Cerebral Aneurysms: Reduction of its Incidence by Microcatheter Lumen Aspiration

PubMed Central

Kim, Dae Yoon; Park, Jung Cheol; Kim, Jae Kyun; Sung, Yu Sub; Park, Eun Suk; Kwak, Jae Hyuk; Choi, Choong-Gon

2015-01-01

Purpose Diffusion-weighted MR images (DWI) obtained after endovascular treatment of cerebral aneurysms frequently show multiple high-signal intensity (HSI) dots. The purpose of this study was to see whether we could reduce their incidence after embolization of unruptured cerebral aneurysms by modification of our coiling technique, which involves the deliberate aspiration of the microcatheter lumen right after delivery of each detachable coil into the aneurysm sac. Materials and Methods From January 2011 to June 2011, all 71 patients with unruptured cerebral aneurysms were treated using various endovascular methods. During the earlier period, 37 patients were treated using our conventional embolization technique (conventional period). Then 34 patients were treated with a modified coiling technique (modified period). DWI was obtained on the following day. We compared the occurrence of any DWI HSI lesions and the presence of the symptomatic lesions during the two time periods. Results The incidence of the DWI HSI lesions differed significantly at 89.2% (33/37) during the conventional period and 26.5% (9/34) during the modified period (p < 0.0001). The incidence of symptomatic lesions differed between the two periods (29.7% during the conventional period vs. 2.9% during the modified period, p < 0.003). Conclusion Aspiration of the inner content of the microcatheter right after detachable coil delivery was helpful for the reduction of the incidence of microembolisms after endovascular coil embolization for the treatment of unruptured cerebral aneurysms. PMID:26389009

Lateral supraorbital approach to ipsilateral PCA-P1 and ICA-PCoA aneurysms

PubMed Central

Goehre, Felix; Jahromi, Behnam Rezai; Elsharkawy, Ahmed; Lehto, Hanna; Shekhtman, Oleg; Andrade-Barazarte, Hugo; Munoz, Francisco; Hijazy, Ferzat; Makhkamov, Makhkam; Hernesniemi, Juha

2015-01-01

Background: Aneurysms of the posterior cerebral artery (PCA) are rare and often associated with anterior circulation aneurysms. The lateral supraorbital approach allows for a very fast and safe approach to the ipsilateral lesions Circle of Willis. A technical note on the successful clip occlusion of two aneurysms in the anterior and posterior Circle of Willis via this less invasive approach has not been published before. The objective of this technical note is to describe the simultaneous microsurgical clip occlusion of an ipsilateral PCA-P1 and an internal carotid artery - posterior communicating artery (ICA-PCoA) aneurysm via the lateral supraorbital approach. Case Description: The authors present a technical report of successful clip occlusions of ipsilateral located PCA-P1 and ICA-PCoA aneurysms. A 59-year-old female patient was diagnosed with a PCA-P1 and an ipsilateral ICA-PCoA aneurysm by computed tomography angiography (CTA) after an ischemic stroke secondary to a contralateral ICA dissection. The patient underwent microsurgical clipping after a lateral supraorbital craniotomy. The intraoperative indocyanine green (ICG) videoangiography and the postoperative CTA showed a complete occlusion of both aneurysms; the parent vessels (ICA and PCA) were patent. The patient presents postoperative no new neurologic deficit. Conclusion: The lateral supraorbital approach is suitable for the simultaneous microsurgical treatment of proximal anterior circulation and ipsilateral proximal PCA aneurysms. Compared to endovascular treatment, direct visual control of brainstem perforators is possible. PMID:26060600

Hemodynamic alterations after stent implantation in 15 cases of intracranial aneurysm.

PubMed

Wang, Chao; Tian, Zhongbin; Liu, Jian; Jing, Linkai; Paliwal, Nikhil; Wang, Shengzhang; Zhang, Ying; Xiang, Jianping; Siddiqui, Adnan H; Meng, Hui; Yang, Xinjian

2016-04-01

Stent-assisted coiling technology has been widely used in the treatment of intracranial aneurysms. In the current study, we investigated the intra-aneurysmal hemodynamic alterations after stent implantation and their association with the aneurysm location. We first retrospectively studied 15 aneurysm cases [8 internal carotid artery-ophthalmic artery (ICA-OphA) aneurysms and 7 posterior communicating artery (PcoA) aneurysms] treated with Enterprise stents and coils. Then, based on the patient-specific geometries before and after stenting, we built virtual stenting computational fluid dynamics (CFD) simulation models. Before and after the stent deployment, the average wall shear stress (WSS) on the aneurysmal sac at systolic peak changed from 7.04 Pa (4.14 Pa, 15.77 Pa) to 6.04 Pa (3.86 Pa, 11.13 Pa), P = 0.001; the spatially averaged flow velocity in the perpendicular plane of the aneurysm dropped from 0.5 m/s (0.28 m/s, 0.7 m/s) to 0.33 m/s (0.25 m/s, 0.49 m/s), P = 0.001, respectively. Post stent implantation, the WSS in ICA-OphA aneurysms and PcoA aneurysms decreased by 14.4 % (P = 0.012) and 16.6 % (P = 0.018), respectively, and the flow velocity also reduced by 10.3 % (P = 0.029) and 10.5 % (P = 0.013), respectively. Changes in the WSS, flow velocity, and pressure were not significantly different between ICA-OphA and PcoA aneurysms (P > 0.05). Stent implantation did not significantly change the peak systolic pressure in either aneurysm type. After the stent implantation, both the intra-aneurysmal flow velocity and WSS decreased independently of aneurysm type (ICA-OphA and PcoA). Little change was observed in peak systolic pressure.

Association of intracranial aneurysm rupture with smoking duration, intensity, and cessation.

PubMed

Can, Anil; Castro, Victor M; Ozdemir, Yildirim H; Dagen, Sarajune; Yu, Sheng; Dligach, Dmitriy; Finan, Sean; Gainer, Vivian; Shadick, Nancy A; Murphy, Shawn; Cai, Tianxi; Savova, Guergana; Dammers, Ruben; Weiss, Scott T; Du, Rose

2017-09-26

Although smoking is a known risk factor for intracranial aneurysm (IA) rupture, the exact relationship between IA rupture and smoking intensity and duration, as well as duration of smoking cessation, remains unknown. In this case-control study, we analyzed 4,701 patients with 6,411 IAs diagnosed at the Brigham and Women's Hospital and Massachusetts General Hospital between 1990 and 2016. We divided individuals into patients with ruptured aneurysms and controls with unruptured aneurysms. We performed univariable and multivariable logistic regression analyses to determine the association between smoking status and ruptured IAs at presentation. In a subgroup analysis among former and current smokers, we assessed the association between ruptured aneurysms and number of packs per day, duration of smoking, and duration since smoking cessation. In multivariable analysis, current (odds ratio [OR] 2.21, 95% confidence interval [CI] 1.89-2.59) and former smoking status (OR 1.56, 95% CI 1.31-1.86) were associated with rupture status at presentation compared with never smokers. In a subgroup analysis among current and former smokers, years smoked (OR 1.02, 95% CI 1.01-1.03) and packs per day (OR 1.46, 95% CI 1.25-1.70) were significantly associated with ruptured aneurysms at presentation, whereas duration since cessation among former smokers was not significant (OR 1.00, 95% CI 0.99-1.02). Current cigarette smoking, smoking intensity, and smoking duration are significantly associated with ruptured IAs at presentation. However, the significantly increased risk persists after smoking cessation, and smoking cessation does not confer a reduced risk of aneurysmal subarachnoid hemorrhage beyond that of reducing the cumulative dose. © 2017 American Academy of Neurology.

Tissue factor levels and the fibrinolytic system in thin and thick intraluminal thrombus and underlying walls of abdominal aortic aneurysms.

PubMed

Siennicka, Aldona; Zuchowski, Marta; Kaczmarczyk, Mariusz; Cnotliwy, Miłosław; Clark, Jeremy Simon; Jastrzębska, Maria

2018-03-20

The hemostatic system cooperates with proteolytic degradation in processes allowing abdominal aortic aneurysm (AAA) formation. In previous studies, it has been suggested that aneurysm rupture depends on intraluminal thrombus (ILT) thickness, which varies across each individual aneurysm. We hypothesized that hemostatic components differentially accumulate in AAA tissue in relation to ILT thickness. Thick (A1) and thin (B1) segments of ILTs and aneurysm wall sections A (adjacent to A1) and B (adjacent to B1) from one aneurysm sac were taken from 35 patients undergoing elective repair. Factor levels were measured using enzyme-linked immunosorbent assay of protein extract. Tissue factor (TF) activities were significantly higher in thinner segments of AAA (B1 vs A1, P = .003; B vs A, P < .001; B vs A1, P < .001; B vs B1, P = .001). Significantly higher tissue plasminogen activator was found in thick thrombus-covered wall segments (A) than in B, A1, and B1 (P = .015, P < .001, and P < .001, respectively). Plasminogen concentrations were highest in ILT. Concentrations of α 2 -antiplasmin in thin ILT adjacent walls (B) were higher compared with wall (A) adjacent to thick ILT (P = .021) and thick ILT (A1; P < .001). Significant correlations between levels of different factors were mostly found in thick ILT (A1). However, no correlations were found at B sites, except for a correlation between plasmin and TF activities (r = 0.55; P = .004). These results suggest that higher TF activities are present in thinner AAA regions. These parameters and local fibrinolysis may be part of the processes leading to destruction of the aneurysm wall. Copyright © 2018 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Are Fetal-Type Posterior Cerebral Arteries Associated With an Increased Risk of Posterior Communicating Artery Aneurysms?

PubMed

Thiarawat, Peeraphong; Jahromi, Behnam Rezai; Kozyrev, Danil A; Intarakhao, Patcharin; Teo, Mario K; Choque-Velasquez, Joham; Niemelä, Mika; Hernesniemi, Juha

2018-05-21

Fetal-type posterior cerebral arteries (F-PCAs) might result in alterations in hemodynamic flow patterns and may predispose an individual to an increased risk of posterior communicating artery aneurysms (PCoAAs). To determine the association between PCoAAs and the presence of ipsilateral F-PCAs. We retrospectively reviewed the radiographic findings from 185 patients harboring 199 PCoAAs that were treated at our institution between 2005 and 2015. Our study population consisted of 4 cohorts: (A) patients with 171 internal carotid arteries (ICAs) harboring unilateral PCoAAs; (B) 171 unaffected ICAs in the same patients from the first group; (C) 28 ICAs of 14 patients with bilateral PCoAAs; and (D) 180 ICAs of 90 patients with aneurysms in other locations. We then determined the presence of ipsilateral F-PCAs and recorded all aneurysm characteristics. Group A had the highest prevalence of F-PCAs (42%) compared to 19% in group B, 3% in group C, and 14% in group D (odds ratio A : B = 3.041; A : C = 19.626; and A : D = 4.308; P < .001). PCoAAs were associated with larger diameters of the posterior communicating arteries (median value 1.05 vs 0.86 mm; P = .001). The presence of F-PCAs was associated with larger sizes of the aneurysm necks (median value 3.3 vs 3.0 mm; P = .02). PCoAAs were associated with a higher prevalence of ipsilateral F-PCAs. This variant was associated with larger sizes of the aneurysm necks but was not associated with the sizes of the aneurysm domes or with their rupture statuses.

Influence of different computational approaches for stent deployment on cerebral aneurysm haemodynamics

PubMed Central

Bernardini, Annarita; Larrabide, Ignacio; Morales, Hernán G.; Pennati, Giancarlo; Petrini, Lorenza; Cito, Salvatore; Frangi, Alejandro F.

2011-01-01

Cerebral aneurysms are abnormal focal dilatations of artery walls. The interest in virtual tools to help clinicians to value the effectiveness of different procedures for cerebral aneurysm treatment is constantly growing. This study is focused on the analysis of the influence of different stent deployment approaches on intra-aneurysmal haemodynamics using computational fluid dynamics (CFD). A self-expanding stent was deployed in an idealized aneurysmatic cerebral vessel in two initial positions. Different cases characterized by a progression of simplifications on stent modelling (geometry and material) and vessel material properties were set up, using finite element and fast virtual stenting methods. Then, CFD analysis was performed for untreated and stented vessels. Haemodynamic parameters were analysed qualitatively and quantitatively, comparing the cases and the two initial positions. All the cases predicted a reduction of average wall shear stress and average velocity of almost 50 per cent after stent deployment for both initial positions. Results highlighted that, although some differences in calculated parameters existed across the cases based on the modelling simplifications, all the approaches described the most important effects on intra-aneurysmal haemodynamics. Hence, simpler and faster modelling approaches could be included in clinical workflow and, despite the adopted simplifications, support clinicians in the treatment planning. PMID:22670204

Is Conventional Open Repair for Abdominal Aortic Aneurysm Feasible in Nonagenarians?

PubMed

Uehara, Kyokun; Matsuda, Hitoshi; Inoue, Yosuke; Omura, Atsushi; Seike, Yoshimasa; Sasaki, Hiroaki; Kobayashi, Junjiro

2017-09-25

Background : Although endovascular repair for abdominal aortic aneurysm has been found to be beneficial in very elderly patients, some patients have contraindications to this procedure. For nonagenarians, the results of open repair remain unclear. The purpose of this study was to compare the outcomes of open vs. endovascular repair for abdominal aortic aneurysm in nonagenarian patients. Methods and Results : Fourteen patients undergoing open surgical repair and 24 undergoing endovascular repair for abdominal aortic aneurysm were evaluated. There was no significant difference in early mortality between the open and endovascular groups (0% vs. 4.1%, p=0.16). The open repair group required much longer hospital stays (26.4 vs. 10.6 days, respectively, p=0.003). Finally, 12 patients (86%) undergoing open repair vs. 21 (88%) undergoing endovascular repair returned home (p=0.49). During a mean follow-up period of 23.4±23.5 months, cumulative estimated 1- and 3-year survival rates were 90.0% and 48.0%, respectively in the open repair group and 90.6% and 54.9%, respectively in the endovascular repair group (p=0.51). Conclusion : Although endovascular repair for abdominal aortic aneurysm was superior in terms of recovery, the results of conventional open repair were acceptable even in nonagenarian patients. Open repair remains an alternative for patients with contraindications to endovascular repair.

Effect of electromagnetic radiation on the coils used in aneurysm embolization.

PubMed

Lv, Xianli; Wu, Zhongxue; Li, Youxiang

2014-06-01

This study evaluated the effects of electromagnetic radiation in our daily lives on the coils used in aneurysm embolization. Faraday's electromagnetic induction principle was applied to analyze the effects of electromagnetic radiation on the coils used in aneurysm embolization. To induce a current of 0.5mA in less than 5 mm platinum coils required to stimulate peripheral nerves, the minimum magnetic field will be 0.86 μT. To induce a current of 0.5 mA in platinum coils by a hair dryer, the minimum aneurysm radius is 2.5 mm (5 mm aneurysm). To induce a current of 0.5 mA in platinum coils by a computer or TV, the minimum aneurysm radius is 8.6 mm (approximate 17 mm aneurysm). The minimum magnetic field is much larger than the flux densities produced by computer and TV, while the minimum aneurysm radius is much larger than most aneurysm sizes to levels produced by computer and TV. At present, the effects of electromagnetic radiation in our daily lives on intracranial coils do not produce a harmful reaction. Patients with coiled aneurysm are advised to avoid using hair dryers. This theory needs to be proved by further detailed complex investigations. Doctors should give patients additional instructions before the procedure, depending on this study.

Effect of Electromagnetic Radiation on the Coils Used in Aneurysm Embolization

PubMed Central

Lv, Xianli; Wu, Zhongxue; Li, Youxiang

2014-01-01

Summary This study evaluated the effects of electromagnetic radiation in our daily lives on the coils used in aneurysm embolization. Faraday’s electromagnetic induction principle was applied to analyze the effects of electromagnetic radiation on the coils used in aneurysm embolization. To induce a current of 0.5mA in less than 5 mm platinum coils required to stimulate peripheral nerves, the minimum magnetic field will be 0.86 μT. To induce a current of 0.5 mA in platinum coils by a hair dryer, the minimum aneurysm radius is 2.5 mm (5 mm aneurysm). To induce a current of 0.5 mA in platinum coils by a computer or TV, the minimum aneurysm radius is 8.6 mm (approximate 17 mm aneurysm). The minimum magnetic field is much larger than the flux densities produced by computer and TV, while the minimum aneurysm radius is much larger than most aneurysm sizes to levels produced by computer and TV. At present, the effects of electromagnetic radiation in our daily lives on intracranial coils do not produce a harmful reaction. Patients with coiled aneurysm are advised to avoid using hair dryers. This theory needs to be proved by further detailed complex investigations. Doctors should give patients additional instructions before the procedure, depending on this study. PMID:24976203

Impact of the moon on cerebral aneurysm rupture.

PubMed

Kamp, Marcel A; Dibué, Maxine; Slotty, Philipp; Steiger, Hans-Jakob; Hänggi, Daniel

2013-08-01

Several external and internal risk factors for cerebral aneurysm rupture have been identified to date. Recently, it has been reported that moon phases correlate with the incidence of aneurysmal subarachnoid hemorrhage (SAH), however, another author found no such association. Therefore, the present study investigates the influence of the lunar cycle on the incidence of aneurysmal rupture, the initial clinical presentation, and the amount of subarachnoid blood. Lunar phase and the particular day of the lunar cycle were correlated to the date of aneurysm rupture, aneurysm location, initial clinical presentation, and amount of subarachnoid blood assessed from CT scans of all patients treated for basal SAH in our department from 2003 to 2010. We found no correlation between incidence of aneurysmal SAH, location of the aneurysm, initial clinical presentation, or amount of subarachnoid blood and the lunar cycle. The moon influences neither the incidence of aneurysmal SAH nor the grade of initial neurological deterioration or amount of subarachnoid blood.

Effect of exercise on patient specific abdominal aortic aneurysm flow topology and mixing

PubMed Central

Arzani, Amirhossein; Les, Andrea S.; Dalman, Ronald L.; Shadden, Shawn C.

2014-01-01

SUMMARY Computational fluid dynamics modeling was used to investigate changes in blood transport topology between rest and exercise conditions in five patient-specific abdominal aortic aneurysm models. Magnetic resonance imaging was used to provide the vascular anatomy and necessary boundary conditions for simulating blood velocity and pressure fields inside each model. Finite-time Lyapunov exponent fields, and associated Lagrangian coherent structures, were computed from blood velocity data, and used to compare features of the transport topology between rest and exercise both mechanistically and qualitatively. A mix-norm and mix-variance measure based on fresh blood distribution throughout the aneurysm over time were implemented to quantitatively compare mixing between rest and exercise. Exercise conditions resulted in higher and more uniform mixing, and reduced the overall residence time in all aneurysms. Separated regions of recirculating flow were commonly observed in rest, and these regions were either reduced or removed by attached and unidirectional flow during exercise, or replaced with regional chaotic and transiently turbulent mixing, or persisted and even extended during exercise. The main factor that dictated the change in flow topology from rest to exercise was the behavior of the jet of blood penetrating into the aneurysm during systole. PMID:24493404

The influence of computational assumptions on analysing abdominal aortic aneurysm haemodynamics.

PubMed

Ene, Florentina; Delassus, Patrick; Morris, Liam

2014-08-01

The variation in computational assumptions for analysing abdominal aortic aneurysm haemodynamics can influence the desired output results and computational cost. Such assumptions for abdominal aortic aneurysm modelling include static/transient pressures, steady/transient flows and rigid/compliant walls. Six computational methods and these various assumptions were simulated and compared within a realistic abdominal aortic aneurysm model with and without intraluminal thrombus. A full transient fluid-structure interaction was required to analyse the flow patterns within the compliant abdominal aortic aneurysms models. Rigid wall computational fluid dynamics overestimates the velocity magnitude by as much as 40%-65% and the wall shear stress by 30%-50%. These differences were attributed to the deforming walls which reduced the outlet volumetric flow rate for the transient fluid-structure interaction during the majority of the systolic phase. Static finite element analysis accurately approximates the deformations and von Mises stresses when compared with transient fluid-structure interaction. Simplifying the modelling complexity reduces the computational cost significantly. In conclusion, the deformation and von Mises stress can be approximately found by static finite element analysis, while for compliant models a full transient fluid-structure interaction analysis is required for acquiring the fluid flow phenomenon. © IMechE 2014.

Endovascular treatment of distal intracranial aneurysms with Onyx 18/34.

PubMed

Chalouhi, Nohra; Tjoumakaris, Stavropoula; Gonzalez, L Fernando; Hasan, David; Alkhalili, Kenan; Dumont, Aaron S; Rosenwasser, Robert; Jabbour, Pascal

2013-12-01

Surgical clipping and coil embolization of distally located intracranial aneurysms can be challenging. The goal of this study was to assess the feasibility, safety and efficacy of treatment of distal aneurysms with the liquid embolic agent Onyx 18/34. Sixteen patients were treated with Onyx 18/34 for distally located aneurysms in our institution between March 2009 and September 2012. The technique consists of occluding the aneurysm as well as the parent vessel at the level of aneurysm with Onyx 18 or 34. Candidates for this treatment were patients with distal aneurysms including mycotic aneurysms, dissecting aneurysms, and pseudoaneurysms in which coiling was considered impossible. Of the 16 patients, 12 presented with subarachnoid and/or intracerebral hemorrhage. Median aneurysm size was 4.6mm. Aneurysm locations were as follows: Posterior inferior cerebellar artery (n=5), distal anterior inferior cerebellar artery (n=3), distal pericallosal (n=3), distal anterior cerebral artery (n=3), lenticulostriate artery (n=1), and anterior ethmoidal artery (n=1). There were 4 mycotic aneurysms. Complete aneurysm obliteration was achieved in all 6 patients with available angiographic follow-up. There was only 1 (6.3%) symptomatic complication in the series. There were no instances of reflux or accidental migration of embolic material. Favorable outcomes were noted in 82% of patients at discharge. Two patients with mycotic aneurysms died from cardiac complications of endocarditis. No aneurysm recanalization or rehemorrhage were seen. Parent vessel trapping with Onyx 18/34 offers a simple, safe, and effective means of achieving obliteration of distal challenging aneurysms. Copyright © 2013 Elsevier B.V. All rights reserved.

Comparison of clipping and coiling in elderly patients with unruptured cerebral aneurysms

PubMed Central

Bekelis, Kimon; Gottlieb, Daniel J.; Su, Yin; O’Malley, A. James; Labropoulos, Nicos; Goodney, Philip; Lawton, Michael T.; MacKenzie, Todd A.

2016-01-01

OBJECTIVE The comparative effectiveness of the 2 treatment options—surgical clipping and endovascular coiling—for unruptured cerebral aneurysms remains an issue of debate and has not been studied in clinical trials. The authors investigated the association between treatment method for unruptured cerebral aneurysms and outcomes in elderly patients. METHODS The authors performed a cohort study of 100% of Medicare fee-for-service claims data for elderly patients who had treatment for unruptured cerebral aneurysms between 2007 and 2012. To control for measured confounding, the authors used propensity score conditioning and inverse probability weighting with mixed effects to account for clustering at the level of the hospital referral region (HRR). An instrumental variable (regional rates of coiling) analysis was used to control for unmeasured confounding and to create pseudo-randomization on the treatment method. RESULTS During the study period, 8705 patients underwent treatment for unruptured cerebral aneurysms and met the study inclusion criteria. Of these patients, 2585 (29.7%) had surgical clipping and 6120 (70.3%) had endovascular coiling. Instrumental variable analysis demonstrated no difference between coiling and clipping in 1-year postoperative mortality (OR 1.25, 95% CI 0.68–2.31) or 90-day readmission rate (OR 1.04, 95% CI 0.66–1.62). However, clipping was associated with a greater likelihood of discharge to rehabilitation (OR 6.39, 95% CI 3.85–10.59) and 3.6 days longer length of stay (LOS; 95% CI 2.90–4.71). The same associations were present in propensity score–adjusted and inverse probability– weighted models. CONCLUSIONS In a cohort of Medicare patients, there was no difference in mortality and the readmission rate between clipping and coiling of unruptured cerebral aneurysms. Clipping was associated with a higher rate of discharge to a rehabilitation facility and a longer LOS. PMID:27203150

Computed tomography angiography spot sign predicts intraprocedural aneurysm rupture in subarachnoid hemorrhage.

PubMed

Burkhardt, Jan-Karl; Neidert, Marian Christoph; Stienen, Martin Nikolaus; Schöni, Daniel; Fung, Christian; Roethlisberger, Michel; Corniola, Marco Vincenzo; Bervini, David; Maduri, Rodolfo; Valsecchi, Daniele; Tok, Sina; Schatlo, Bawarjan; Bijlenga, Philippe; Schaller, Karl; Bozinov, Oliver; Regli, Luca

2017-07-01

To analyze whether the computed tomography angiography (CTA) spot sign predicts the intraprocedural rupture rate and outcome in patients with aneurysmal subarachnoid hemorrhage (aSAH). From a prospective nationwide multicenter registry database, 1023 patients with aneurysmal subarachnoid hemorrhage (aSAH) were analyzed retrospectively. Descriptive statistics and logistic regression analysis were used to compare spot sign-positive and -negative patients with aneurysmal intracerebral hemorrhage (aICH) for baseline characteristics, aneurysmal and ICH imaging characteristics, treatment and admission status as well as outcome at discharge and 1-year follow-up (1YFU) using the modified Rankin Scale (mRS). A total of 218 out of 1023 aSAH patients (21%) presented with aICH including 23/218 (11%) patients with spot sign. Baseline characteristics were comparable between spot sign-positive and -negative patients. There was a higher clip-to-coil ratio in patients with than without aICH (both spot sign positive and negative). Median aICH volume was significantly higher in the spot sign-positive group (50 ml, 13-223 ml) than in the spot sign-negative group (18 ml, 1-416; p < 0.0001). Patients with a spot sign-positive aICH thus were three times as likely as those with spot sign-negative aICH to show an intraoperative aneurysm rupture [odds ratio (OR) 3.04, 95% confidence interval (CI) 1.04-8.92, p = 0.046]. Spot sign-positive aICH patients showed a significantly worse mRS at discharge (p = 0.039) than patients with spot sign-negative aICH (median mRS 5 vs. 4). Logistic regression analysis showed that the spot sign was an aICH volume-dependent predictor for outcome. Both spot sign-positive and -negative aICH patients showed comparable rates of hospital death, death at 1YFU and mRS at 1YFU. In this multicenter data analysis, patients with spot sign-positive aICH showed higher aICH volumes and a higher rate of intraprocedural aneurysm rupture, but comparable long-term outcome to spot sign-negative aICH patients.

High-resolution CFD detects high-frequency velocity fluctuations in bifurcation, but not sidewall, aneurysms.

PubMed

Valen-Sendstad, Kristian; Mardal, Kent-André; Steinman, David A

2013-01-18

High-frequency flow fluctuations in intracranial aneurysms have previously been reported in vitro and in vivo. On the other hand, the vast majority of image-based computational fluid dynamics (CFD) studies of cerebral aneurysms report periodic, laminar flow. We have previously demonstrated that transitional flow, consistent with in vivo reports, can occur in a middle cerebral artery (MCA) bifurcation aneurysm when ultra-high-resolution direct numerical simulation methods are applied. The object of the present study was to investigate if such high-frequency flow fluctuations might be more widespread in adequately-resolved CFD models. A sample of N=12 anatomically realistic MCA aneurysms (five unruptured, seven ruptured), was digitally segmented from CT angiograms. Four were classified as sidewall aneurysms, the other eight as bifurcation aneurysms. Transient CFD simulations were carried out assuming a steady inflow velocity of 0.5m/s, corresponding to typical peak systolic conditions at the MCA. To allow for detection of clinically-reported high-frequency flow fluctuations and resulting flow structures, temporal and spatial resolutions of the CFD simulations were in the order of 0.1 ms and 0.1 mm, respectively. A transient flow response to the stationary inflow conditions was found in five of the 12 aneurysms, with energetic fluctuations up to 100 Hz, and in one case up to 900 Hz. Incidentally, all five were ruptured bifurcation aneurysms, whereas all four sidewall aneurysms, including one ruptured case, quickly reached a stable, steady state solution. Energetic, rapid fluctuations may be overlooked in CFD models of bifurcation aneurysms unless adequate temporal and spatial resolutions are used. Such fluctuations may be relevant to the mechanobiology of aneurysm rupture, and to a recently reported dichotomy between predictors of rupture likelihood for bifurcation vs. sidewall aneurysms. Copyright © 2012 Elsevier Ltd. All rights reserved.

Growth of Untreated Unruptured Small-sized Aneurysms (≺7mm): Incidence and Related Factors.

PubMed

Choi, Hyun Ho; Cho, Young Dae; Jeon, Jin Pyeong; Yoo, Dong Hyun; Moon, Jusun; Lee, Jeongjun; Kang, Hyun-Seung; Cho, Won-Sang; Kim, Jeong Eun; Zhang, Li; Han, Moon Hee

2018-06-01

The need to treat small (<7 mm) unruptured aneurysms is still controversial, despite data collected through several large cohort studies. Such lesions typically are incidental findings, usually followed for potential growth through serial imaging. For this study, growth estimates for untreated unruptured small-sized aneurysms were generated, examining incidence and related risk factors. A cohort of 135 consecutive patients harboring 173 untreated unruptured small-sized aneurysms (<7 mm) was subjected to extended monitoring (mean, 73.1 ± 30.0 months). Growth was defined as a 1-mm increase at minimum in one or more aneurysmal dimensions or as a significant change in shape. Medical records and radiological data were reviewed. Cumulative growth rate and related risk factors were analyzed via Cox proportional hazards regression and Kaplan-Meier product-limit estimator. A total of 28 aneurysms (16.2%) displayed growth during continued surveillance (1054.1 aneurysm-years). The annual growth rate was 2.65% per aneurysm-year, with 15 surfacing within 60 months and 13 after 60 months. Multivariate analysis indicated that bifurcation type was the sole significant risk factor (hazard ratio HR = 7.64; p < 0.001) in terms of growth. Cumulative survival rates without growth were significantly lower in subjects with bifurcation aneurysms than with side-wall aneurysms (p < 0.001). During the follow-up period, one patient suffered a subarachnoid hemorrhage and then aneurysm growth was detected. Most (83.8%) untreated unruptured small-sized aneurysms (<7 mm) remained stable and devoid of growth in long-term follow-up. Because bifurcation aneurysms were prone to eventual growth, careful long-term monitoring at regular intervals is advised if left untreated.

Highly accelerated intracranial 4D flow MRI: evaluation of healthy volunteers and patients with intracranial aneurysms.

PubMed

Liu, Jing; Koskas, Louise; Faraji, Farshid; Kao, Evan; Wang, Yan; Haraldsson, Henrik; Kefayati, Sarah; Zhu, Chengcheng; Ahn, Sinyeob; Laub, Gerhard; Saloner, David

2018-04-01

To evaluate an accelerated 4D flow MRI method that provides high temporal resolution in a clinically feasible acquisition time for intracranial velocity imaging. Accelerated 4D flow MRI was developed by using a pseudo-random variable-density Cartesian undersampling strategy (CIRCUS) with the combination of k-t, parallel imaging and compressed sensing image reconstruction techniques (k-t SPARSE-SENSE). Four-dimensional flow data were acquired on five healthy volunteers and eight patients with intracranial aneurysms using CIRCUS (acceleration factor of R = 4, termed CIRCUS4) and GRAPPA (R = 2, termed GRAPPA2) as the reference method. Images with three times higher temporal resolution (R = 12, CIRCUS12) were also reconstructed from the same acquisition as CIRCUS4. Qualitative and quantitative image assessment was performed on the images acquired with different methods, and complex flow patterns in the aneurysms were identified and compared. Four-dimensional flow MRI with CIRCUS was achieved in 5 min and allowed further improved temporal resolution of <30 ms. Volunteer studies showed similar qualitative and quantitative evaluation obtained with the proposed approach compared to the reference (overall image scores: GRAPPA2 3.2 ± 0.6; CIRCUS4 3.1 ± 0.7; CIRCUS12 3.3 ± 0.4; difference of the peak velocities: -3.83 ± 7.72 cm/s between CIRCUS4 and GRAPPA2, -1.72 ± 8.41 cm/s between CIRCUS12 and GRAPPA2). In patients with intracranial aneurysms, the higher temporal resolution improved capturing of the flow features in intracranial aneurysms (pathline visualization scores: GRAPPA2 2.2 ± 0.2; CIRCUS4 2.5 ± 0.5; CIRCUS12 2.7 ± 0.6). The proposed rapid 4D flow MRI with a high temporal resolution is a promising tool for evaluating intracranial aneurysms in a clinically feasible acquisition time.

Microsurgical management of basilar artery apex aneurysms: a single surgeon's experience from Louisiana State University, Shreveport.

PubMed

Nanda, Anil; Sonig, Ashish; Banerjee, Anirban Deep; Javalkar, Vijay Kumar

2014-01-01

Basilar artery apex aneurysms continue to generate technical challenges and management controversy. Endovascular intervention is becoming the mainstay in the management of these formidable aneurysms, but it has limitations, especially with large/giant or wide neck basilar apex aneurysms. There is paucity of data in the available literature pertaining to the successful management of large/giant, wide neck, and calcified/thrombosed basilar apex aneurysms. We present our experience with consecutively operated complex basilar apex aneurysms so as to present the role of microneurosurgery as a viable management option for these aneurysms. Ours is a retrospective analysis of case-records for operated cases of basilar artery aneurysms spanning 18 years. Basilar apex aneurysms >10 cm, calcified or thrombosed, neck ≥4 mm posterior direction, and retro/subsellar were considered as complex anatomy aneurysms. Basilar apex aneurysms with favorable anatomy were included in the study as a reference group for statistical analysis. Patient demographics, complex features of aneurysms, clinical grade, and outcomes were analyzed. A total of 33 (53.2%) patients had complex anatomy: large (>10 mm) in eight (24.2%); giant aneurysms (>25 mm) in seven (21.2%); wide-neck in 22 (66.7%); and calcified/thrombosed morphology in five (15.1%). The mean age was 48.5 years, and 22 (66.67%) were women. All aneurysms were clipped by the use of various skull base approaches. A total of 71.9% of patients harboring complex aneurysm had good outcomes. If only unruptured and good grade complex aneurysms also are considered, then 86.9% (n = 20) patients had good outcomes. Statistically there was no significant difference in the outcomes of complex and noncomplex aneurysm. Although concerning, the management of large/giant, wide neck, and calcified/thrombosed aneurysms with microneurosurgery is still a competitive alternative to endovascular therapy. After careful selection of appropriate skull base approaches based on the complexity of the basilar apex aneurysm, microneurosurgery can achieve acceptable results. Copyright © 2014 Elsevier Inc. All rights reserved.

The Monocyte Chemotactic Protein-1 — Interleukin-6 — Osteopontin Pathway of Intra-Aneurysmal Tissue Healing

PubMed Central

Hosaka, Koji; Rojas, Kelley; Fazal, Hanain Z; Schneider, Matheus B; Shores, Jorma; Federico, Vincent; McCord, Matthew; Lin, Li; Hoh, Brian

2017-01-01

Background and Purpose We have previously demonstrated that the local delivery of monocyte chemotactic protein-1 (MCP-1) via a MCP-1-releasing poly(lactic-co-glycolic acid) (PLGA) -coated coil promotes intra-aneurysmal tissue healing. In this study, we demonstrate that interleukin-6 (IL-6) and osteopontin (OPN) are downstream mediators in the MCP-1-mediated aneurysm healing pathway. Methods Murine carotid aneurysms were created in C57BL/6 mice. Drug-releasing coils (MCP-1, IL-6 and OPN) and control PLGA coils were created and then implanted into the aneurysms in order to evaluate their intra-aneurysmal healing capacity. In order to investigate the downstream mediators for aneurysm healing, blocking antibodies for IL-6 receptor and OPN were given to the mice implanted with the MCP-1-releasing coils. A histological analysis of both murine and human aneurysms was utilized to cross-validate the data. Results We observed increased expression of IL-6 in MCP-1-coil treated aneurysms and not in control-PLGA-only treated aneurysms. MCP-1-mediated intra-aneurysmal healing is inhibited in mice given blocking antibody to IL-6 receptor. MCP-1-mediated intra-aneurysmal healing is also inhibited by blocking antibody to OPN. The role of IL-6 in intra-aneurysmal healing is in recruiting of endothelial cells and fibroblasts. Local delivery of OPN to murine carotid aneurysms via OPN-releasing coil significantly promotes intra-aneurysmal healing, but IL-6-releasing coil does not, suggesting that IL-6 cannot promote aneurysm healing independent of MCP-1. In the MCP-1-mediated aneurysm healing, OPN expression is dependent on IL-6; inhibition of IL-6 receptor significantly inhibits OPN expression in MCP-1-mediated aneurysm healing. Conclusions Our findings suggest that IL-6 and OPN are key downstream mediators of MCP-1-mediated intra-aneurysmal healing. PMID:28292871

Vortex dynamics in ruptured and unruptured intracranial aneurysms

NASA Astrophysics Data System (ADS)

Trylesinski, Gabriel

Intracranial aneurysms (IAs) are a potentially devastating pathological dilation of brain arteries that affect 1.5-5 % of the population. Causing around 500 000 deaths per year worldwide, their detection and treatment to prevent rupture is critical. Multiple recent studies have tried to find a hemodynamics predictor of aneurysm rupture, but concluded with distinct opposite trends using Wall Shear Stress (WSS) based parameters in different clinical datasets. Nevertheless, several research groups tend to converge for now on the fact that the flow patterns and flow dynamics of the ruptured aneurysms are complex and unstable. Following this idea, we investigated the vortex properties of both unruptured and ruptured cerebral aneurysms. A brief comparison of two Eulerian vortex visualization methods (Q-criterion and lambda 2 method) showed that these approaches gave similar results in our complex aneurysm geometries. We were then able to apply either one of them to a large dataset of 74 patient specific cases of intracranial aneurysms. Those real cases were obtained by 3D angiography, numerical reconstruction of the geometry, and then pulsatile CFD simulation before post-processing with the mentioned vortex visualization tools. First we tested the two Eulerian methods on a few cases to verify their implementation we made as well as compare them with each other. After that, the Q-criterion was selected as method of choice for its more obvious physical meaning (it shows the balance between two characteristics of the flow, its swirling and deformation). Using iso-surfaces of Q, we started by categorizing the patient-specific aneurysms based on the gross topology of the aneurysmal vortices. This approach being unfruitful, we found a new vortex-based characteristic property of ruptured aneurysms to stratify the rupture risk of IAs that we called the Wall-Kissing Vortices, or WKV. We observed that most ruptured aneurysms had a large amount of WKV, which appears to agree with the current hypothesized biological triggers of pathological remodeling of the artery walls. Having a good natural ratio of statuses in our IA cohort (55 unruptured vs. 19 ruptured), we were able to test the statistical significance of our predictor to fortify our findings. We also performed a distribution analysis of our cohort with respect to the number of WKV to strengthen the encouraging statistical analysis result; both analyses provided a clear good separation of the status of the aneurysms based on our predictor. Lastly, we constructed a receiver operating characteristic (ROC) curve to analyze the power different thresholds of WKV had in splitting the data in a binary way (unruptured/ruptured). The number of WKV was efficaciously able to stratify the rupture status, identifying 84.21 % of the ruptured aneurysms (with 25.45 % of false positives, i.e. unruptured IAs tagged as ruptured) when using a threshold value of 2. Our novel work undertaken to study the vortex structures in IAs brought to light interesting characteristics of the flow in the aneurysmal sac. We found that there are several distinct categories in which the aneurysm vortex topologies can be put in without relationship to the aneurysm rupture status. This first finding was in contradiction with available already-published results. Nonetheless, ruptured IAs had a statistically significant larger amount of WKV as opposed to unruptured aneurysms. This new predictor we propose to the community could very well clear a new path among the currently controversial WSS-based parameters. Although it needs to be improved to be more resilient, the first results obtained by the WKV-based parameter are promising when applied to a large dataset of 74 IAs patient-specific transient CFD simulations.

Computational study for the effects of coil configuration on blood flow characteristics in coil-embolized cerebral aneurysm.

PubMed

Otani, Tomohiro; Ii, Satoshi; Shigematsu, Tomoyoshi; Fujinaka, Toshiyuki; Hirata, Masayuki; Ozaki, Tomohiko; Wada, Shigeo

2017-05-01

Coil embolization of cerebral aneurysms with inhomogeneous coil distribution leads to an incomplete occlusion of the aneurysm. However, the effects of this factor on the blood flow characteristics are still not fully understood. This study investigates the effects of coil configuration on the blood flow characteristics in a coil-embolized aneurysm using computational fluid dynamics (CFD) simulation. The blood flow analysis in the aneurysm with coil embolization was performed using a coil deployment (CD) model, in which the coil configuration was constructed using a physics-based simulation of the CD. In the CFD results, total flow momentum and kinetic energy in the aneurysm gradually decayed with increasing coil packing density (PD), regardless of the coil configuration attributed to deployment conditions. However, the total shear rate in the aneurysm was relatively high and the strength of the local shear flow varied based on the differences in coil configuration, even at adequate PDs used in clinical practice (20-25 %). Because the sufficient shear rate reduction is a well-known factor in the blood clot formation occluding the aneurysm inside, the present study gives useful insight into the effects of coil configuration on the treatment efficiency of coil embolization.

Influence of morphology and hemodynamic factors on rupture of multiple intracranial aneurysms: matched-pairs of ruptured-unruptured aneurysms located unilaterally on the anterior circulation.

PubMed

Zhang, Ying; Yang, Xinjian; Wang, Yang; Liu, Jian; Li, Chuanhui; Jing, Linkai; Wang, Shengzhang; Li, Haiyun

2014-12-31

The authors evaluated the impact of morphological and hemodynamic factors on the rupture of matched-pairs of ruptured-unruptured intracranial aneurysms on one patient's ipsilateral anterior circulation with 3D reconstruction model and computational fluid dynamic method simulation. 20 patients with intracranial aneurysms pairs on the same-side of anterior circulation but with different rupture status were retrospectively collected. Each pair was divided into ruptured-unruptured group. Patient-specific models based on their 3D-DSA images were constructed and analyzed. The relative locations, morphologic and hemodynamic factors of these two groups were compared. There was no significant difference in the relative bleeding location. The morphological factors analysis found that the ruptured aneurysms more often had irregular shape and had significantly higher maximum height and aspect ratio. The hemodynamic factors analysis found lower minimum wall shear stress (WSSmin) and more low-wall shear stress-area (LSA) in the ruptured aneurysms than that of the unruptured ones. The ruptured aneurysms more often had WSSmin on the dome. Intracranial aneurysms pairs with different rupture status on unilateral side of anterior circulation may be a good disease model to investigate possible characteristics linked to rupture independent of patient characteristics. Irregular shape, larger size, higher aspect ratio, lower WSSmin and more LSA may indicate a higher risk for their rupture.

Anti-fibrinolytic treatment in the pre-operative management of subarachnoid haemorrhage caused by ruptured intracranial aneurysm.

PubMed Central

Ameen, A A; Illingworth, R

1981-01-01

One hundred consecutive patients treated with epsilon aminocaproic acid 24 grams daily prior to surgery for ruptured intracranial aneurysms have been compared with the previous 100 patients managed similarly but without anti-fibrinolytic drugs. No other alterations in management were made and the two series are closely comparable in all other respects. Fewer episodes of recurrent haemorrhage and deaths from this cause occurred in the treated patients, but more cases of cerebral ischaemia occurred. Neither difference is statistically significant and overall more deaths occurred in the patients treated with antifibrinolytic drugs. The value of this method of treatment in the management of aneurysmal subarachnoid haemorrhage is questioned. PMID:7229645

Three-dimensional workstation is useful for measuring the correct size of abdominal aortic aneurysm diameters.

PubMed

Ihara, Tsutomu; Komori, Kimihiro; Yamamoto, Kiyohito; Kobayashi, Masayoshi; Banno, Hiroshi; Kodama, Akio

2013-02-01

Abdominal aortic aneurysm diameter is usually measured by the maximum minor-axis diameter on axial computed tomography (CT). However, this "traditional" diameter may underestimate the real size, as the aorta is not always straight and the aneurysm shape is sometimes in the form of an ellipse along the cross section. Therefore, we measured maximum major-axis diameters using a three-dimensional (3D) workstation and compared them with the traditional maximum minor-axis diameters measured using thin-slice axial CT. CT data of 141 AAA patients (with fusiform aneurysms) were stored in a 3D workstation. These thin-slice CT images were reviewed on the 3D workstation to obtain curved multiplanar reconstruction images (CPR images). Using the CPR images, we measured the maximum major-axis and minor-axis diameters on CPR and the angle of the aneurysms to the body axis. The mean traditional maximum minor-axis diameter was 51.2 ± 8.2 mm, whereas the mean maximum major-axis diameter on CPR was 54.7 ± 10.1 mm. Sixty eight patients had a mean aneurysm size of <50 mm when measured by the traditional minor-axis diameter. Among these patients, five (7.4%) had a major-axis diameter >55 mm on CPR. The measurement of the traditional maximum minor-axis diameter of aneurysms is useful in the case of most patients. However, the traditional maximum minor-axis diameter may underestimate the real aneurysmal diameter, particularly in patients with an ellipse-shaped aneurysm. The maximum major-axis diameter as measured using CPR images is effective for representing the real aneurysmal size. Copyright © 2013 Elsevier Inc. All rights reserved.

Endoluminal Reconstruction for Nonsaccular Aneurysms of the Proximal Posterior Cerebral Artery with the Pipeline Embolization Device.

PubMed

Zumofen, D W; Shapiro, M; Becske, T; Raz, E; Potts, M B; Riina, H A; Nelson, P K

2015-07-01

Treatment options for nonsaccular posterior cerebral artery aneurysms include a range of surgical and endovascular reconstructive and deconstructive methods. However, no truly satisfactory treatment option is available to date for lesions arising from the P1 and P2 segments. The purpose of the present case series is to investigate both the efficacy and safety of the Pipeline Embolization Device in treating these challenging aneurysms. We present a series of 6 consecutive patients who underwent endoluminal reconstruction with the Pipeline Embolization Device for nonsaccular P1 or P2 segment aneurysms between January 2009 and June 2013. Aneurysm location included the P1 segment in 2 patients and the P2 segment in 4 patients. Mean aneurysm diameter was 23 mm (range, 5-44 mm). Mean length of the arterial segment involved was 10 mm (range, 6-19 mm). Clinical presentation included mass effect in 4 patients and perforator stroke and subacute aneurysmal subarachnoid hemorrhage in 1 patient each. Endovascular reconstruction was performed by using 1 Pipeline Embolization Device in 5 patients and 2 overlapping Pipeline Embolization Devices in the remaining patient. Angiographic aneurysm occlusion was immediate in 1 patient, within 6 months in 4 patients, and within 1 year in the remaining patient. Index symptoms resolved in 4 patients and stabilized in the remaining 2. No new permanent neurologic sequelae and no aneurysm recurrence were recorded during the mean follow-up period of 613 days (range, 540-725 days). Endovascular reconstruction with the Pipeline Embolization Device for nonsaccular aneurysms arising from the P1 and P2 segments compares favorably with historical treatment options in terms of occlusion rate, margin of safety, and neurologic outcome. © 2015 by American Journal of Neuroradiology.

Compared to controls, patients with ruptured aneurysm and surgical intervention show increase in symptoms of depression and lower cognitive performance, but their objective sleep is not affected.

PubMed

Brand, Serge; Zimmerer, Stefan; Kalak, Nadeem; Planta, Sandra Von; Schwenzer-Zimmerer, Katja; Müller, Andreas Albert; Zeilhofer, Hans-Florian; Holsboer-Trachsler, Edith

2015-02-01

Patients with aneurysmal subarachnoid haemorrhage (aSAH) have impaired sleep and cognitive performance together with more difficulties in social and everyday life. Hypocortisolism has also been reported. However, a study assessing all dimensions between aSAH severity, objective and subjective sleep, cortisol secretion, cognitive performance and social and everyday life has not so far been performed. The aim of the present study was therefore two-fold: (1) to assess, in a sample of patients with aSAH, objective and subjective sleep, cognitive functioning, social skills and cortisol secretion concurrently, and (2) to compare patients on these variables with a control group. Twenty-one patients (17 females; mean age: 58.80 years) with ruptured aneurysm and surgical intervention and 21 (14 females; mean age: 58.90 years) age- and gender-matched controls took part in the study. Assessments covered objective sleep-EGG recordings, subjective sleep, salivary cortisol analysis, and psychological functioning including memory performance, mood, and emotion recognition. Compared to healthy controls, patients had lower scores for verbal memory performance and emotion recognition; they also reported more marked depressive symptoms and complained of poor sleep. However, no differences were found for objective sleep or cortisol secretion. Subjective and objective sleep, cortisol secretion and psychological functioning were unrelated. Findings indicate that patients with aSAH face psychological rather than physiological issues.

Aspirin and Clopidogrel Inhibit Aneurysm Healing after HydroCoil Implantation in External Carotid Artery Aneurysm Model.

PubMed

Zhang, Chao; Li, Peiliang; Xi, Guohua; Gemmete, Joseph J; Chaudhary, Neeraj; Thompson, B Gregory; Pandey, Aditya S

2016-11-01

To understand whether the use of antiplatelet agents leads to less intra-aneurismal tissue formation following coil implantation in a rat end-pouch external carotid artery (ECA) aneurysm model. End-pouch ECA aneurysms were created in adult rats and were then embedded with either platinum or HydroCoils. Rats were treated either with aspirin, clopidogrel, aspirin + clopidogrel, or saline for 2 weeks after coil implantation. At 2 weeks after coil implantation, rats were sacrificed and the aneurysm pouch was removed for histological and immunohistochemical analysis. A blinded single observer calculated the percentage of the organized area and the residual length of elastic lamina within the aneurysm. Student's t-test was used to compare data from image analysis between the different groups. Within the platinum group, the organized tissue area was not affected by antiplatelet administration (aspirin versus saline, P = .83; clopidogrel versus saline, P = .46; aspirin + clopidogrel versus saline, P = .54). For the HydroCoil group, the organized tissue area was significantly reduced (aspirin versus saline, P = .02; clopidogrel versus saline, P = .04; aspirin + clopidogrel versus saline, P = .02) in rats treated with antiplatelet agents; however, no difference (aspirin versus clopidogrel, P = .8; aspirin versus aspirin + clopidogrel, P = .3; clopidogrel versus aspirin + clopidogrel, P = .5) was found among type or combination of antiplatelets administered. HydroCoil-treated aneurysms had a similar number of macrophages compared to the platinum group (P = .3819); however, the HydroCoil group had significant suppression of macrophages in the groups treated with combined antiplatelets (P = .02). Following HydroCoil implantation, the area of organized tissue is diminished significantly in a rat end-pouch ECA aneurysm model treated with antiplatelets. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Contrast-Enhanced and Time-of-Flight MRA at 3T Compared with DSA for the Follow-Up of Intracranial Aneurysms Treated with the WEB Device.

PubMed

Timsit, C; Soize, S; Benaissa, A; Portefaix, C; Gauvrit, J-Y; Pierot, L

2016-09-01

Imaging follow-up at 3T of intracranial aneurysms treated with the WEB Device has not been evaluated yet. Our aim was to assess the diagnostic accuracy of 3D-time-of-flight MRA and contrast-enhanced MRA at 3T against DSA, as the criterion standard, for the follow-up of aneurysms treated with the Woven EndoBridge (WEB) system. From June 2011 to December 2014, patients treated with the WEB in our institution, then followed for ≥6 months after treatment by MRA at 3T (3D-TOF-MRA and contrast-enhanced MRA) and DSA within 48 hours were included. Aneurysm occlusion was assessed with a simplified 2-grade scale (adequate occlusion [total occlusion + neck remnant] versus aneurysm remnant). Interobserver and intermodality agreement was evaluated by calculating the linear weighted κ. MRA test characteristics and predictive values were calculated from a 2 × 2 contingency table, by using DSA data as the standard of reference. Twenty-six patients with 26 WEB-treated aneurysms were included. The interobserver reproducibility was good with DSA (κ = 0.71) and contrast-enhanced-MRA (κ = 0.65) compared with moderate with 3D-TOF-MRA (κ = 0.47). Intermodality agreement with DSA was fair with both contrast-enhanced MRA (κ = 0.36) and 3D-TOF-MRA (κ = 0.36) for the evaluation of total occlusion. For aneurysm remnant detection, the prevalence was low (15%), on the basis of DSA, and both MRA techniques showed low sensitivity (25%), high specificity (100%), very good positive predictive value (100%), and very good negative predictive value (88%). Despite acceptable interobserver reproducibility and predictive values, the low sensitivity of contrast-enhanced MRA and 3D-TOF-MRA for aneurysm remnant detection suggests that MRA is a useful screening procedure for WEB-treated aneurysms, but similar to stents and flow diverters, DSA remains the criterion standard for follow-up. © 2016 by American Journal of Neuroradiology.

Posterior inferior cerebellar artery aneurysms: Anatomical variations and surgical strategies

PubMed Central

Singh, Rohit K.; Behari, Sanjay; Kumar, Vijendra; Jaiswal, Awadhesh K.; Jain, Vijendra K.

2012-01-01

Context: Posterior inferior cerebellar artery (PICA) aneurysms are associated with multiple anatomical variations of the parent vessel. Complexities in their surgical clipping relate to narrow corridors limited by brain-stem, petrous-occipital bones, and multiple neurovascular structures occupying the cerebellomedullary and cerebellopontine cisterns. Aims: The present study focuses on surgical considerations during clipping of saccular PICA aneurysms. Setting and Design: Tertiary care, retrospective study. Materials and Methods: In 20 patients with PICA aneurysms, CT angiogram/digital substraction angiogram was used to correlate the site and anatomical variations of aneurysms located on different segments of PICA with the approach selected, the difficulties encountered and the final outcome. Statistical Analysis: Comparison of means and percentages. Results: Aneurysms were located on PICA at: vertebral artery/basilar artery (VA/BA)-PICA (n=5); anterior medullary (n=4); lateral medullary (n=3); tonsillomedullary (n=4); and, telovelotonsillar (n=4) segments. The Hunt and Hess grade distribution was I in 15; II in 2; and, III in 3 patients (mean ictus-surgery interval: 23.5 days; range: 3-150 days). Eight patients had hydrocephalus. Anatomical variations included giant, thrombosed aneurysms; 2 PICA aneurysms proximal to an arteriovenous malformation; bilobed or multiple aneurysms; low PICA situated at the foramen magnum with a hypoplastic VA; and fenestrated PICA. The approaches included a retromastoid suboccipital craniectomy (n=9); midline suboccipital craniectomy (n=6); and far-lateral approach (n=5). At a follow-up (range 6 months-2.5 years), 13 patients had no deficits (modified Rankin score (mRS) 0); 2 were symptomatic with no significant disability (mRS1); 1 had mild disability (mRS2); 1 had moderately severe disability (mRS4); and 3 died (mRS6). Three mortalities were caused by vasospasm (2) and, rupture of unclipped second VA-BA junctional aneurysm (1). Conclusions: PICA aneurysms may present with only IVth ventricular blood without subarachnoid hemorrhage. PICA may have multiple anomalies and its aneurysms may be missed on CT angiograms. Surgical approach is influenced by VA-BA tortuosity and variations in anatomy, location of the VA-BA junction and the PICA aneurysm relative to the brain-stem, and the pattern of collateral supply. The special category of VA-PICA junctional aneurysms and its management; and, the multiple anatomical variations of PICA aneurysms, merit special surgical considerations and have been highlighted in this study. PMID:22639684

Microsurgical subtemporal approach to aneurysms on the P(2) segment of the posterior cerebral artery.

PubMed

Zhitao, Jing; Yibao, Wang; Anhua, Wu; Shaowu, Ou; Yunchao, Ban; Renyi, Zhou; Yunjie, Wang

2010-01-01

Aneurysms arising from the P(2) segment of the posterior cerebral artery (PCA) are rare, accounting for less than 1% of all intracranial aneurysms. To date, few studies concerning the management of P(2) segment aneurysms have been reported. To review the microsurgical techniques and clinical outcomes of microsurgical treatment by different approaches in patients with aneurysms on the P(2) segment of the PCA. Forty-two patients with P2 segment aneurysms had microsurgical treatment by subtemporal approach. All the patients had drainage of cerebrospinal fluid for decompression, and indocyanine green (ICG) angiography was used in 20 patients to assess the effect of clipping. Of the 42 patients, 16 were operated by combined pterional-subtemporal approach. In 40 patients aneurysms were successfully treated by clipping the P(2) aneurysmal neck while preserving the parent artery. Two patients with giant aneurysms were treated using surgical trapping. Postoperatively, 41 patients had a good recovery. One patient after aneurysm trapping had ischemic infarction in the PCA tertiary and presented with hemiparesis and homonymous hemianopia. However, this patient recovered after three weeks of treatment. Subtemporal approach is the most appropriate approach to clip the aneurysms of the P(2) segment. It allows the neurosurgeon to operate on the aneurysms while preserving the patency of the parent artery. Gaint P(2) segment aneurysms can safely be treated by rapping of the aneurysm by combined subtemporal or pterional-subtemporal approach in experienced hands. ICG angiography will be an important tool in monitoring for the presence of residual aneurysm or perforating artery occlusion during aneurysm clipping. Preoperative lumbar drainage of cerebrospinal fluid may help to avoid temporal lobe damage.

Y stenting assisted coiling using a new low profile visible intraluminal support device for wide necked basilar tip aneurysms: a technical report.

PubMed

Conrad, Marcelo D; Brasiliense, Leonardo B C; Richie, Alexa N; Hanel, Ricardo A

2014-05-01

Many endovascular techniques have been described in recent years for the management of wide necked aneurysms. The Y stent assisted technique has been generally used for coil embolization of wide necked bifurcation aneurysms. This technique was first described for the treatment of basilar tip aneurysms in combination with several different devices, demonstrating encouraging results. We report the results of the first two cases of wide necked basilar tip aneurysms treated with Y stent assisted coil embolization using a new low profile visible intraluminal stent (LVIS Jr; MicroVention, Tustin, California, USA) delivered through a 0.017 inch microcatheter. We also reviewed the literature comparing other endovascular techniques (coiling alone, stent assisted coiling, and Y stent assisted coiling) for wide necked aneurysms. The LVIS Jr device offers a new option for the treatment of these challenging lesions, with clear advantages over currently available intracranial stents. Larger series and long term results are needed to confirm the applicability and durability of this technique/technology.

Experimental Study of Flow Through Carotid Aneurysms

NASA Astrophysics Data System (ADS)

Masoomi, Faezeh; Mejia-Alvarez, Ricardo

2017-11-01

There is evidence that traditional endovascular techniques like coiling are not effective for treatment of wide-neck cerebral aneurysms. Flow Diverter Stents (FDS) have emerged as promising devices for treating complex aneurysms since they enable treatment of aneurysms that were considered untreatable before. Recent studies suggest a number of associated risks with FDS, including in-stent thrombosis, perianeurysmal edema, delayed hemorrhage, and perforator occlusions. Chong et al. simulated hemodynamic behavior using patient-specific data. From their study, it is possible to infer that the standard deviation of energy loss could be a good predictor for intervention success. The aim of this study is to investigate the flow in models of cerebral aneurysms before and after FDS insertion using PIV. These models will be based on actual clinical studies and will be fabricated with advanced additive manufacturing techniques. These data will then be used to explore flow parameters that could inform the likelihood of post-intervention aneurysm rupture, and help determine FDS designs that better suit any particular patient before its procedure.

A Multicenter Cohort Comparison Study of the Safety, Efficacy, and Cost of Ticagrelor Compared to Clopidogrel in Aneurysm Flow Diverter Procedures.

PubMed

Moore, Justin M; Adeeb, Nimer; Shallwani, Hussain; Gupta, Raghav; Patel, Apar S; Griessenauer, Christoph J; Youn, Roy; Siddiqui, Adnan; Ogilvy, Christopher S; Thomas, Ajith J

2017-10-01

Thromboembolic and hemorrhagic complications are among the most feared adverse events in the endovascular treatment of aneurysms, and this is particularly the case for flow diverter devices. Dual antiplatelet therapy has become standard of care; however, the safety, efficacy, and cost profiles of newer antiplatelet agents are not well characterized in the neurovascular context. To compare the safety, efficacy, and cost of one of these newer agents, ticagrelor, to the most frequently used agent, clopidogrel. A multicenter, retrospective, cohort comparison study design of consecutively treated aneurysms with flow diverter embolization device and treated with either ticagrelor or clopidogrel was performed. Data were collected on patient demographics and risk factors, procedural details, antiplatelet treatment regime, complications, and angiographic and functional outcomes. Fifty patients undergoing flow diverter device deployment and treatment with ticagrelor were compared to 53 patients undergoing flow diversion and treatment with clopidogrel. The patients' age, sex, smoking status, aneurismal morphology and size, and procedural details did not differ between the 2 groups; neither did the rate of thromboembolic and hemorrhagic complications, angiographical, and functional outcomes. Ticagrelor was more expensive when compared to clopidogrel. Ticagrelor is a safe and effective agent for prevention of thromboembolic complications following flow diverter deployment when compared to clopidogrel. However, ticagrelor remains significantly more expensive than clopidogrel, and, thus, we would advise ticagrelor be reserved for patients who are hyporesponsive to clopidogrel. Copyright © 2017 by the Congress of Neurological Surgeons

Safety and efficacy of aneurysm treatment with WEB: results of the WEBCAST study.

PubMed

Pierot, Laurent; Costalat, Vincent; Moret, Jacques; Szikora, Istvan; Klisch, Joachim; Herbreteau, Denis; Holtmannspötter, Markus; Weber, Werner; Januel, Anne-Christine; Liebig, Thomas; Sychra, Vojtech; Strasilla, Christoph; Cognard, Christophe; Bonafé, Alain; Molyneux, Andrew; Byrne, James V; Spelle, Laurent

2016-05-01

OBJECT WEB is an innovative intrasaccular treatment for intracranial aneurysms. Preliminary series have shown good safety and efficacy. The WEB Clinical Assessment of Intrasaccular Aneurysm Therapy (WEBCAST) trial is a prospective European trial evaluating the safety and efficacy of WEB in wide-neck bifurcation aneurysms. METHODS Patients with wide-neck bifurcation aneurysms for which WEB treatment was indicated were included in this multicentergood clinical practices study. Clinical data including adverse events and clinical status at 1 and 6 months were collected and independently analyzed by a medical monitor. Six-month follow-up digital subtraction angiography was also performed and independently analyzed by a core laboratory. Success was defined at 6 months as complete occlusion or stable neck remnant, no worsening in angiographic appearance from postprocedure, and no retreatment performed or planned. RESULTS Ten European neurointerventional centers enrolled 51 patients with 51 aneurysms. Treatment with WEB was achieved in 48 of 51 aneurysms (94.1%). Adjunctive implants (coils/stents) were used in 4 of 48 aneurysms (8.3%). Thromboembolic events were observed in 9 of 51 patients (17.6%), resulting in a permanent deficit (modified Rankin Scale [mRS] Score 1) in 1 patient (2.0%). Intraoperative rupture was not observed. Morbidity (mRS score > 2) and mortality were 2.0% (1 of 51 patients, related to rupture status on entry to study) and 0.0% at 1 month, respectively. Success was achieved at 6 months in 85.4% of patients treated with WEB: 23 of 41 patients (56.1%) had complete occlusion, 12 of 41 (29.3%) had a neck remnant, and 6 of 41 (14.6%) had an aneurysm remnant. CONCLUSIONS The WEBCAST study showed good procedural and short-term safety of aneurysm treatment with WEB and good 6-month anatomical results.

Association of statins with aortic, peripheral, and visceral artery aneurysm development.

PubMed

Mansi, Ishak A; Frei, Christopher R; Halm, Ethan A; Mortensen, Eric M

2017-08-01

Objectives Prior studies examining the effects of statins on arterial aneurysm development and progression yielded conflicting results due to their smaller size and presence of residual confounders. The objective of this study is to examine the association of statins with risk of being diagnosed with aortic, peripheral, and visceral artery aneurysm. Methods This was a retrospective cohort study of Tricare enrollees (from 1 October 2003 to 31 March 2012). Main outcomes were diagnosis of aortic, peripheral, or visceral artery aneurysm and undergoing aortic aneurysm repair procedure during follow-up period. Using 115 baseline characteristics, we generated a propensity score to match statin users and nonusers and examine the odds of outcomes (primary analysis). Secondary analysis examined outcomes at various subcohorts. Results Out of 10,910 statin users and 49,545 nonusers, we propensity score-matched 6728 pairs of statin users and nonusers. Statin users and nonusers had similar odds of being diagnosed with aortic, peripheral, and visceral artery aneurysms (odds ratio [OR]: 1.06, 95% confidence interval [95% CI]: 0.85-1.33) and of undergoing aortic aneurysm repair procedures (OR: 0.54, 95% CI: 0.22-1.35). Secondary analysis showed a tendency toward fewer aortic aneurysm procedures among statin users that did not reach statistical significance. However, high-intensity statin users in comparison to non-intensive statin users had higher adjusted odds of aortic, peripheral, and visceral artery aneurysms (OR: 1.76, 95% CI: 1.37-2.25, p < .0001). Conclusions This study does not support a clinically significant benefit or harm from statins regarding development of arterial aneurysm. However, secondary analyses may support the hypothesis proposed by previous research proposing a bidirectional role for statins.

Benchtop quantification of gutter formation and compression of chimney stent grafts in relation to renal flow in chimney endovascular aneurysm repair and endovascular aneurysm sealing configurations.

PubMed

Boersen, Johannes T; Donselaar, Esme J; Groot Jebbink, Erik; Starreveld, Roeliene; Overeem, Simon P; Slump, Cornelis H; de Vries, Jean-Paul P M; Reijnen, Michel M P J

2017-11-01

The chimney technique has been successfully used to treat juxtarenal aortic aneurysms. The two main issues with this technique are gutter formation and chimney graft (CG) compression, which induce a risk for type Ia endoleaks and stent thrombosis, respectively. In this benchtop study, the geometry and renal artery flow of chimney endovascular aneurysm repair configurations were compared with chimney configurations with endovascular aneurysm sealing (ch-EVAS). Seven flow phantoms were constructed, including one control and six chimney endovascular aneurysm repairs (Endurant [Medtronic Inc, Minneapolis, Minn] and AFX [Endologix Inc, Irvine, Calif]) or ch-EVAS (Nellix, Endologix) configurations, combined with either balloon-expandable or self-expanding CGs with an intended higher positioning of the right CG in comparison to the left CG. Geometric analysis was based on measurements at three-dimensional computed tomography angiography and included gutter volume and CG compression, quantified by the ratio between maximal and minimal diameter (D-ratio). In addition, renal artery flow was studied in a physiologic flow model and compared with the control. The average gutter volume was 343.5 ± 142.0 mm 3 , with the lowest gutter volume in the EVAS-Viabahn (W. L. Gore & Associates, Flagstaff, Ariz) combination (102.6 mm 3 ) and the largest in the AFX-Advanta V12 (Atrium Medical Corporation, Hudson, NH) configuration (559.6 mm 3 ). The maximum D-ratio was larger in self-expanding CGs than in balloon-expandable CGs in all configurations (2.02 ± 0.34 vs 1.39 ± 0.13). The CG compression had minimal influence on renal volumetric flow (right, 390.7 ± 29.4 mL/min vs 455.1 mL/min; left, 423.9 ± 28.3 mL/min vs 410.0 mL/min in the control). This study showed that gutter volume was lowest in ch-EVAS in combination with a Viabahn CG. CG compression was lower in configurations with the Advanta V12 than with Viabahn. Renal flow is unrestricted by CG compression. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Propose a Wall Shear Stress Divergence to Estimate the Risks of Intracranial Aneurysm Rupture

PubMed Central

Zhang, Y.; Takao, H.; Murayama, Y.; Qian, Y.

2013-01-01

Although wall shear stress (WSS) has long been considered a critical indicator of intracranial aneurysm rupture, there is still no definite conclusion as to whether a high or a low WSS results in aneurysm rupture. The reason may be that the effect of WSS direction has not been fully considered. The objectives of this study are to investigate the magnitude of WSS (|WSS|) and its divergence on the aneurysm surface and to test the significance of both in relation to the aneurysm rupture. Patient-specific computational fluid dynamics (CFD) was used to compute WSS and wall shear stress divergence (WSSD) on the aneurysm surface for nineteen patients. Our results revealed that if high |WSS| is stretching aneurysm luminal surface, and the stretching region is concentrated, the aneurysm is under a high risk of rupture. It seems that, by considering both direction and magnitude of WSS, WSSD may be a better indicator for the risk estimation of aneurysm rupture (154). PMID:24191140

Prevention of abdominal aortic aneurysm progression by targeted inhibition of matrix metalloproteinase activity with batimastat-loaded nanoparticles.

PubMed

Nosoudi, Nasim; Nahar-Gohad, Pranjal; Sinha, Aditi; Chowdhury, Aniqa; Gerard, Patrick; Carsten, Christopher G; Gray, Bruce H; Vyavahare, Naren R

2015-11-06

Matrix metalloproteinases (MMPs)-mediated extracellular matrix destruction is the major cause of development and progression of abdominal aortic aneurysms. Systemic treatments of MMP inhibitors have shown effectiveness in animal models, but it did not translate to clinical success either because of low doses used or systemic side effects of MMP inhibitors. We propose a targeted nanoparticle (NP)-based delivery of MMP inhibitor at low doses to the abdominal aortic aneurysms site. Such therapy will be an attractive option for preventing expansion of aneurysms in patients without systemic side effects. Our previous study showed that poly(d,l-lactide) NPs conjugated with an antielastin antibody could be targeted to the site of an aneurysm in a rat model of abdominal aortic aneurysms. In the study reported here, we tested whether such targeted NPs could deliver the MMP inhibitor batimastat (BB-94) to the site of an aneurysm and prevent aneurysmal growth. Poly(d,l-lactide) NPs were loaded with BB-94 and conjugated with an elastin antibody. Intravenous injections of elastin antibody-conjugated BB-94-loaded NPs targeted the site of aneurysms and delivered BB-94 in a calcium chloride injury-induced abdominal aortic aneurysms in rats. Such targeted delivery inhibited MMP activity, elastin degradation, calcification, and aneurysmal development in the aorta (269% expansion in control versus 40% elastin antibody-conjugated BB-94-loaded NPs) at a low dose of BB-94. The systemic administration of BB-94 alone at the same dose was ineffective in producing MMP inhibition. Targeted delivery of MMP inhibitors using NPs may be an attractive strategy to inhibit aneurysmal progression. © 2015 American Heart Association, Inc.

EARLYDRAIN- outcome after early lumbar CSF-drainage in aneurysmal subarachnoid hemorrhage: study protocol for a randomized controlled trial

PubMed Central

2011-01-01

Background Aneurysmal subarachnoid hemorrhage (SAH) may be complicated by delayed cerebral ischemia, which is a major cause of unfavorable clinical outcome and death in SAH-patients. Delayed cerebral ischemia is presumably related to the development of vasospasm triggered by the presence of blood in the basal cisterns. To date, oral application of the calcium antagonist nimodipine is the only prophylactic treatment for vasospasm recognized under international guidelines. In retrospective trials lumbar drainage of cerebrospinal fluid has been shown to be a safe and feasible measure to remove the blood from the basal cisterns and decrease the incidence of delayed cerebral ischemia and vasospasm in the respective study populations. However, the efficacy of lumbar drainage has not been evaluated prospectively in a randomized controlled trial yet. Methods/Design This is a protocol for a 2-arm randomized controlled trial to compare an intervention group receiving early continuous lumbar CSF-drainage and standard neurointensive care to a control group receiving standard neurointensive care only. Adults suffering from a first aneurysmal subarachnoid hemorrhage whose aneurysm has been secured by means of coiling or clipping are eligible for trial participation. The effect of early CSF drainage (starting < 72 h after securing the aneurysm) will be measured in the following ways: the primary endpoint will be disability after 6 months, assessed by a blinded investigator during a personal visit or standardized telephone interview using the modified Rankin Scale. Secondary endpoints include mortality after 6 months, angiographic vasospasm, transcranial Doppler sonography (TCD) mean flow velocity in both middle cerebral arteries and rate of shunt insertion at 6 months after hospital discharge. Discussion Here, we present the study design of a multicenter prospective randomized controlled trial to investigate whether early application of a lumbar drainage improves clinical outcome after aneurysmal subarachnoid hemorrhage. Trial registration www.clinicaltrials.gov Identifier: NCT01258257 PMID:21917146

First long-term evidence supporting endovascular repair of abdominal aortic aneurysms.

PubMed

Indes, Jeffrey E; Muhs, Bart E; Dardik, Alan

2013-04-01

The traditional method of treating abdominal aortic aneurysms with open surgical repair has been steadily replaced by endovascular repair, thought to be a more minimally invasive approach. It is not known, however, whether the endovascular approach is truly less invasive for operative physiology; in addition, this approach has a different spectrum of complications. As such, it is uncertain whether elective endovascular repair of nonruptured aortic aneurysms reduces long-term morbidity and mortality compared with traditional open approaches. In this article, the authors evaluate a recent publication investigating long-term outcomes of a prospective randomized multicenter trial evaluating patients with asymptomatic abdominal aortic aneurysms treated with either endovascular or open repair, and discuss the results in the context of current evidence.

Microballoon Occlusion Test to Predict Colonic Ischemia After Transcatheter Embolization of a Ruptured Aneurysm of the Middle Colic Artery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tajima, Tsuyoshi, E-mail: ttajima@med.kyushu-u.ac.jp; Yoshimitsu, Kengo; Inokuchi, Hiroyuki

2008-07-15

A 76-year-old woman presented with sudden massive melena, and superior mesenteric arteriography showed an aneurysm in the middle colic artery (MCA). Because she had a history of right hemicolectomy and ligation of the inferior mesenteric artery (IMA) during open abdominal aortic aneurysm repair, embolization of the MCA aneurysm was considered to pose a risk comparable to that of colonic ischemia. A microballoon occlusion test during occlusion of the MCA confirmed retrograde visualization of the IMA branches through the collateral arteries by way of the left internal iliac artery, and embolization was successfully performed using microcoils. No colonic ischemia or aneurysmmore » rupture occurred after embolization.« less

Combining two potential causes of metalloproteinase secretion causes abdominal aortic aneurysms in rats: a new experimental model

PubMed Central

Mata, Karina M; Prudente, Paula S; Rocha, Fabio S; Prado, Cibele M; Floriano, Elaine M; Elias, Jorge; Rizzi, Elen; Gerlach, Raquel F; Rossi, Marcos A; Ramos, Simone G

2011-01-01

Progress in understanding the pathophysiology of abdominal aortic aneurysms (AAA) is dependent in part on the development and application of effective animal models that recapitulate key aspects of the disease. The objective was to produce an experimental model of AAA in rats by combining two potential causes of metalloproteinase (MMP) secretion: inflammation and turbulent blood flow. Male Wistar rats were randomly divided in four groups: Injury, Stenosis, Aneurysm and Control (40/group). The Injury group received a traumatic injury to the external aortic wall. The Stenosis group received an extrinsic stenosis at a corresponding location. The Aneurysm group received both the injury and stenosis simultaneously, and the Control group received a sham operation. Animals were euthanized at days 1, 3, 7 and 15. Aorta and/or aneurysms were collected and the fragments were fixed for morphologic, immunohistochemistry and morphometric analyses or frozen for MMP assays. AAAs had developed by day 3 in 60–70% of the animals, reaching an aortic dilatation ratio of more than 300%, exhibiting intense wall remodelling initiated at the adventitia and characterized by an obvious inflammatory infiltrate, mesenchymal proliferation, neoangiogenesis, elastin degradation and collagen deposition. Immunohistochemistry and zymography studies displayed significantly increased expressions of MMP-2 and MMP-9 in aneurysm walls compared to other groups. The haemo-dynamic alterations caused by the stenosis may have provided additional contribution to the MMPs liberation. This new model illustrated that AAA can be multifactorial and confirmed the key roles of MMP-2 and MMP-9 in this dynamic remodelling process. PMID:21039990

Risk of abdominal aortic aneurysm (AAA) among male and female relatives of AAA patients.

PubMed

van de Luijtgaarden, Koen M; Rouwet, Ellen V; Hoeks, Sanne E; Stolker, Robert J; Verhagen, Hence Jm; Majoor-Krakauer, Danielle

2017-04-01

Sex affects the presentation, treatment, and outcomes of abdominal aortic aneurysm (AAA). Although AAAs are less prevalent in women, at least in the general population, women with an AAA have a poorer prognosis in comparison to men. Sex differences in the genetic predisposition for aneurysm disease remain to be established. In this study we investigated the familial risk of AAA for women compared to men. All living AAA patients included in a 2004-2012 prospective database were invited to the multidisciplinary vascular/genetics outpatient clinic between 2009 and 2012 for assessment of family history using detailed questionnaires. AAA risk for male and female relatives was calculated separately and stratified by sex of the AAA patients. Families of 568 AAA patients were investigated and 22.5% of the patients had at least one affected relative. Female relatives had a 2.8-fold and male relatives had a 1.7-fold higher risk than the estimated sex-specific population risk. Relatives of female AAA patients had a higher aneurysm risk than relatives of male patients (9.0 vs 5.9%, p = 0.022), corresponding to 5.5- and 2.0-fold increases in aneurysm risk in the female and male relatives, respectively. The risk for aortic aneurysm in relatives of AAA patients is higher than expected from population risk. The excess risk is highest for the female relatives of AAA patients and for the relatives of female AAA patients. These findings endorse targeted AAA family screening for female and male relatives of all AAA patients.

Microsurgical clipping of ophthalmic artery aneurysms: surgical results and visual outcomes with 208 aneurysms.

PubMed

Kamide, Tomoya; Tabani, Halima; Safaee, Michael M; Burkhardt, Jan-Karl; Lawton, Michael T

2018-01-26

OBJECTIVE While most paraclinoid aneurysms can be clipped with excellent results, new postoperative visual deficits are a concern. New technology, including flow diverters, has increased the popularity of endovascular therapy. However, endovascular treatment of paraclinoid aneurysms is not without procedural risks, is associated with higher rates of incomplete aneurysm occlusion and recurrence, and may not address optic nerve compression symptoms that surgical debulking can. The increasing endovascular management of paraclinoid aneurysms should be justified by comparisons to surgical benchmarks. The authors, therefore, undertook this study to define patient, visual, and aneurysm outcomes in the most common type of paraclinoid aneurysm: ophthalmic artery (OphA) aneurysms. METHODS Results from microsurgical clipping of 208 OphA aneurysms in 198 patients were retrospectively reviewed. Patient demographics, aneurysm morphology (size, calcification, etc.), clinical characteristics, and patient outcomes were recorded and analyzed. RESULTS Despite 20% of these aneurysms being large or giant in size, complete aneurysm occlusion was accomplished in 91% of 208 cases, with OphA patency preserved in 99.5%. The aneurysm recurrence rate was 3.1% and the retreatment rate was 0%. Good outcomes (modified Rankin Scale score 0-2) were observed in 96.2% of patients overall and in all 156 patients with unruptured aneurysms. New visual field defects (hemianopsia or quadrantanopsia) were observed in 8 patients (3.8%), decreased visual acuity in 5 (2.4%), and monocular blindness in 9 (4.3%). Vision improved in 9 (52.9%) of the 17 patients with preoperative visual deficits. CONCLUSIONS The most important risk associated with clipping OphA aneurysms is a new visual deficit. Meticulous microsurgical technique is necessary during anterior clinoidectomy, aneurysm dissection, and clip application to optimize visual outcomes, and aggressive medical management postoperatively might potentially decrease the incidence of delayed visual deficits. As the results of endovascular therapy and specifically flow diverters become known, they warrant comparison with these surgical benchmarks to determine best practices.

True posterior communicating artery aneurysms: are they more prone to rupture? A biomorphometric analysis.

PubMed

He, Wenzhuan; Hauptman, Jason; Pasupuleti, Latha; Setton, Avi; Farrow, Maria G; Kasper, Lydia; Karimi, Reza; Gandhi, Chirag D; Catrambone, Jeffrey E; Prestigiacomo, Charles J

2010-03-01

Posterior communicating artery (PCoA) aneurysms can occur at the junction with the internal carotid artery, posterior cerebral artery (PCA), or the proximal PCoA itself. Hemodynamic stressors contribute to aneurysm formation and may be associated with parent vessel size and aneurysm location. This study evaluates the correlation of various biomorphometric characteristics in 2 of the aforementioned types of PCoA aneurysms. Patients with PCoA aneurysms were analyzed using CT angiography. Source images and reconstructions were used to determine which aneurysms originated purely from the PCoA and those that originated from the internal carotid artery/PCoA junction. Morphometric analysis was performed on the aneurysm, the precommunicating segment of the PCA (P(1)), the ambient segment of the PCA (P(2)), and both PCoA arteries and were correlated to clinical presentation. Parametric and nonparametric analyses were performed to test for significance. A total of 77 PCoA aneurysms were analyzed, and 10 were found to be true PCoA aneurysms (13.0%). The ipsilateral PCoA/P(1) ratio (1.77 +/- 0.44 vs 0.82 +/- 0.46, p = 0.0001) and ipsilateral P(2)/P(1) ratio (1.73 +/- 0.40 vs 1.22 +/- 0.41, p = 0.0003) were significantly larger in true PCoA aneurysms. Interestingly, aneurysm size was statistically larger in the junctional aneurysms (0.14 +/- 0.1 vs 0.072 +/- 0.04 cm(3), p = 0.03). The prevalence of ruptured aneurysms was similar in both groups (approximately 80%, p value not significant). These data suggest that true PCoA aneurysms have a larger PCoA relative to the ipsilateral P(1) segment. To the authors' knowledge, this represents the first such biomorphometric comparison of these different types of PCoA aneurysms. Although statistically smaller in size, true PCoA aneurysms also have a similar prevalence of presenting as a ruptured aneurysm, suggesting that they might be more prone to rupture than a junctional aneurysms of similar size. Further analysis will be required to determine the biophysical factors affecting rupture rates.

Contemporary management of isolated iliac aneurysms.

PubMed

Krupski, W C; Selzman, C H; Floridia, R; Strecker, P K; Nehler, M R; Whitehill, T A

1998-07-01

Because isolated common iliac artery aneurysms are infrequent, are difficult to detect and treat, and have traditionally been associated with high operative mortality rates in reported series, we analyzed the outcomes of operative repair of 31 isolated common iliac artery aneurysms in 21 patients to ascertain morbidity and mortality rates with contemporary techniques of repair. A retrospective review study was conducted in a university teaching hospital and a Department of Veterans Affairs Medical Center. Perioperative mortality and operative morbidity rates were examined in 17 men and four women with isolated common iliac artery aneurysms between 1984 and 1997. Ages ranged from 38 to 87 years (mean 69 +/- 8 years). Slightly more than half of the cases were symptomatic, with abdominal pain, neurologic, claudicative, genitourinary, or hemodynamic symptoms. One aneurysm had ruptured and one was infected. There was one iliac artery-iliac vein fistula. All aneurysms involved the common iliac artery. Coexistent unilateral or bilateral external iliac aneurysms were present in four patients; there were three accompanying internal iliac aneurysms. Overall, 52% of patients had unilateral aneurysms and 48% had bilateral aneurysms. Aneurysms ranged in maximal diameter from 2.5 to 12 cm (mean 5.6 +/- 2 cm). No patients were unavailable for follow-up, which averaged 5.5 years. Nineteen patients underwent direct operative repair of isolated iliac aneurysms. One patient had placement of an endoluminal covered stent graft; another patient at high risk had percutaneous placement of coils within the aneurysm to occlude it in conjunction with a femorofemoral bypass graft. Patients with bilateral aneurysms underwent aortoiliac or aortofemoral interposition grafts, whereas unilateral aneurysms were managed with local interposition grafts. There were no deaths in the perioperative period. Only one elective operation (5%) resulted in a significant complication, compartment syndrome requiring fasciotomy. The patient treated with the covered stent required femorofemoral bypass when the stent occluded 1 week after the operation. The patient treated with coil occlusion of a large common iliac aneurysm died 2 years later when the aneurysm ruptured. Isolated iliac artery aneurysms can be managed with much lower mortality and morbidity rates than aneurysm previously been reported by using a systematic operative approach. Percutaneous techniques may be less durable and effective than direct surgical repair.

Dimorphic effects of transforming growth factor-β signaling during aortic aneurysm progression in mice suggest a combinatorial therapy for Marfan syndrome.

PubMed

Cook, Jason R; Clayton, Nicholas P; Carta, Luca; Galatioto, Josephine; Chiu, Emily; Smaldone, Silvia; Nelson, Carol A; Cheng, Seng H; Wentworth, Bruce M; Ramirez, Francesco

2015-04-01

Studies of mice with mild Marfan syndrome (MFS) have correlated the development of thoracic aortic aneurysm (TAA) with improper stimulation of noncanonical (Erk-mediated) TGFβ signaling by the angiotensin type I receptor (AT1r). This correlation was largely based on comparable TAA modifications by either systemic TGFβ neutralization or AT1r antagonism. However, subsequent investigations have called into question some key aspects of this mechanism of arterial disease in MFS. To resolve these controversial points, here we made a head-to-head comparison of the therapeutic benefits of TGFβ neutralization and AT1r antagonism in mice with progressively severe MFS (Fbn1(mgR/mgR) mice). Aneurysm growth, media degeneration, aortic levels of phosphorylated Erk and Smad proteins and the average survival of Fbn1(mgR/mgR) mice were compared after a ≈3-month-long treatment with placebo and either the AT1r antagonist losartan or the TGFβ-neutralizing antibody 1D11. In contrast to the beneficial effect of losartan, TGFβ neutralization either exacerbated or mitigated TAA formation depending on whether treatment was initiated before (postnatal day 16; P16) or after (P45) aneurysm formation, respectively. Biochemical evidence-related aneurysm growth with Erk-mediated AT1r signaling, and medial degeneration with TGFβ hyperactivity that was in part AT1r dependent. Importantly, P16-initiated treatment with losartan combined with P45-initiated administration of 1D11 prevented death of Fbn1(mgR/mgR) mice from ruptured TAA. By demonstrating that promiscuous AT1r and TGFβ drive partially overlapping processes of arterial disease in MFS mice, our study argues for a therapeutic strategy against TAA that targets both signaling pathways although sparing the early protective role of TGFβ. © 2015 American Heart Association, Inc.

The effect of inlet waveforms on computational hemodynamics of patient-specific intracranial aneurysms.

PubMed

Xiang, J; Siddiqui, A H; Meng, H

2014-12-18

Due to the lack of patient-specific inlet flow waveform measurements, most computational fluid dynamics (CFD) simulations of intracranial aneurysms usually employ waveforms that are not patient-specific as inlet boundary conditions for the computational model. The current study examined how this assumption affects the predicted hemodynamics in patient-specific aneurysm geometries. We examined wall shear stress (WSS) and oscillatory shear index (OSI), the two most widely studied hemodynamic quantities that have been shown to predict aneurysm rupture, as well as maximal WSS (MWSS), energy loss (EL) and pressure loss coefficient (PLc). Sixteen pulsatile CFD simulations were carried out on four typical saccular aneurysms using 4 different waveforms and an identical inflow rate as inlet boundary conditions. Our results demonstrated that under the same mean inflow rate, different waveforms produced almost identical WSS distributions and WSS magnitudes, similar OSI distributions but drastically different OSI magnitudes. The OSI magnitude is correlated with the pulsatility index of the waveform. Furthermore, there is a linear relationship between aneurysm-averaged OSI values calculated from one waveform and those calculated from another waveform. In addition, different waveforms produced similar MWSS, EL and PLc in each aneurysm. In conclusion, inlet waveform has minimal effects on WSS, OSI distribution, MWSS, EL and PLc and a strong effect on OSI magnitude, but aneurysm-averaged OSI from different waveforms has a strong linear correlation with each other across different aneurysms, indicating that for the same aneurysm cohort, different waveforms can consistently stratify (rank) OSI of aneurysms. Copyright © 2014 Elsevier Ltd. All rights reserved.

Does the gravity orientation of saccular aneurysms influence hemodynamics? An experimental study with and without flow diverter stent.

PubMed

Chodzyński, Kamil J; Eker, Omer F; Vanrossomme, Axel E; de Sousa, Daniel Ribeiro; Coussement, Grégory; Vanhamme, Luc; Dubois, Frank; Bonafé, Alain; Chopard, Bastien; Courbebaisse, Guy; Zouaoui Boudjeltia, Karim

2016-12-08

Most intracranial aneurysms morphologic studies focused on characterization of size, location, aspect ratio, relationship to the surrounding vasculature and hemodynamics. However, the spatial orientation with respect to the gravity direction has not been taken into account although it could trigger various hemodynamic conditions. The present work addresses this possibility. It was divided in two parts: 1) the orientations of 18, 3D time-of-flight MRI (3D TOF MRI), scans of saccular aneurysms were analyzed. This investigation suggested that there was no privileged orientation for cerebral aneurysms. The aneurysms were oriented in the brain as follows: 9 - down, 9 - up; 11 - right, 7 - left; 6 - front, 12 - back. 2) Based on these results, subsidiary in vitro experiments were performed, analyzing the behavior of red blood cells (RBCs) within a silicone model of aneurysm before and after flow diverter stent (FDS) deployment in the parent vessel. These experiments used a test bench that reproduces physiological pulsatile flow conditions for two orientations: an aneurysm sack pointing either up (opposite to gravitational force) and down (along the gravitational force). The results showed that the orientation of an aneurysm significantly affects the intra-aneurysmal RBCs behavior after stenting, and therefore that gravity can affect the intra-aneurysm behavior of RBCs. This suggests that the patient׳s aneurysm orientation could impact the outcome of the FDS treatment. The implementation of this effect in patient-specific numerical and preoperative decision support techniques could contribute to better understand the intrasaccular biological and hemodynamic events induced by FDS. Copyright © 2016 Elsevier Ltd. All rights reserved.

3D-Printed Visceral Aneurysm Models Based on CT Data for Simulations of Endovascular Embolization: Evaluation of Size and Shape Accuracy.

PubMed

Shibata, Eisuke; Takao, Hidemasa; Amemiya, Shiori; Ohtomo, Kuni

2017-08-01

The objective of this study is to verify the accuracy of 3D-printed hollow models of visceral aneurysms created from CT angiography (CTA) data, by evaluating the sizes and shapes of aneurysms and related arteries. From March 2006 to August 2015, 19 true visceral aneurysms were embolized via interventional radiologic treatment provided by the radiology department at our institution; aneurysms with bleeding (n = 3) or without thin-slice (< 1 mm) preembolization CT data (n = 1) were excluded. A total of 15 consecutive true visceral aneurysms from 11 patients (eight women and three men; mean age, 61 years; range, 53-72 years) whose aneurysms were embolized via endovascular procedures were included in this study. Three-dimensional-printed hollow models of aneurysms and related arteries were fabricated from CTA data. The accuracies of the sizes and shapes of the 3D-printed hollow models were evaluated using the nonparametric Wilcoxon signed rank test and the Dice coefficient index. Aneurysm sizes ranged from 138 to 18,691 mm 3 (diameter, 6.1-35.7 mm), and no statistically significant difference was noted between patient data and 3D-printed models (p = 0.56). Shape analysis of whole aneurysms and related arteries indicated a high level of accuracy (Dice coefficient index value, 84.2-95.8%; mean [± SD], 91.1 ± 4.1%). The sizes and shapes of 3D-printed hollow visceral aneurysm models created from CTA data were accurate. These models can be used for simulations of endovascular treatment and precise anatomic information.

Aneurysm treatment practice patterns for newly appointed dual-trained cerebrovascular/endovascular neurosurgeons: Comparison of open surgical to neuroendovascular procedures in the first 2 years of academic practice.

PubMed

Jiang, Bowen; Bender, Matthew T; Hasjim, Bima; Hsu, Frank P K; Tamargo, Rafael J; Huang, Judy; Colby, Geoffrey P; Coon, Alexander L; Lin, Li-Mei

2017-01-01

The practice patterns of a hybrid open cerebrovascular/neuroendovascular (CVNV) neurosurgeon in early academic practice is unknown. We performed a multi-institutional retrospective cohort study of patients with cerebral aneurysms that were treated within the first 24 months of the neurosurgeon's practice. A total of 533 aneurysms were treated by the three senior authors within the first 24 months of their academic practice. Of these aneurysms, 172 were treated with microsurgical clipping, 191 with coiling, and 170 with flow diversion. Treatment in the setting of acute subarachnoid hemorrhage (SAH) occurred in 23% (122/533) of the aneurysms. Majority of the clipped aneurysms (70%, 121/172) were anterior cerebral artery (ACA), anterior communicating artery (ACOM), or middle cerebral artery (MCA) in location. In comparison, only 23% (82/361) of aneurysms treated with coiling or flow diversion therapy were ACA, ACOM, or MCA in location ( P < 0.05). Additionally, majority of the flow diverted aneurysm (65%, 111/170) were cavernous or ophthalmic/paraophthalmic in location. During the second year of practice, there appeared to be a trend towards more aneurysms treated with neuroendovascular techniques (22% increase), particularly in flow diversion. Although the CVNV neurosurgeon treats cerebral aneurysms more commonly with neuroendovascular techniques, a third of the cerebral aneurysms are still selected for microsurgical clipping. Aneurysms located along the ACA/ACOM or MCA are the most frequent aneurysms reserved for microsurgical clipping. The CVNV neurosurgeon must be prepared to manage a high percentage of ACA/ACOM or MCA aneurysms microsurgically.

Controlled hypotension versus normotensive resuscitation strategy for people with ruptured abdominal aortic aneurysm.

PubMed

Moreno, Daniel H; Cacione, Daniel G; Baptista-Silva, Jose C C

2016-05-13

An abdominal aortic aneurysm (AAA) is the pathological enlargement of the aorta and can develop in both men and women. Progressive aneurysm enlargement can lead to rupture. The rupture of an AAA is frequently fatal and accounts for the death from haemorrhagic shock of at least 45 people per 100,000 population. The outcome of people with ruptured AAA varies among countries and healthcare systems, with mortality ranging from 53% to 90%. Definitive treatment for ruptured AAA includes open surgery or endovascular repair. The management of haemorrhagic shock is crucial for the person's outcome and aims to restore organ perfusion and systolic blood pressure above 100 mm Hg through immediate and aggressive fluid replacement. This rapid fluid replacement is known as the normotensive resuscitation strategy. However, evidence suggests that infusing large volumes of cold fluid causes dilutional and hypothermic coagulopathy. The association of these factors may exacerbate bleeding, resulting in a 'lethal triad' of hypothermia, acidaemia, and coagulopathy. An alternative to the normotensive resuscitation strategy is the controlled (permissive) hypotension resuscitation strategy, with a target systolic blood pressure of 50 to 100 mm Hg. The principle of controlled or hypotensive resuscitation has been used in some management protocols for endovascular repair of ruptured AAA. It may be beneficial in preventing blood loss by avoiding the clot disruption caused by the rapid increase in systolic blood pressure; avoiding dilution of clotting factors, platelets and fibrinogen; and by avoiding the temperature decrease that inhibits enzyme activity involved in platelet and clotting factor function. To compare the effects of controlled (permissive) hypotension resuscitation and normotensive resuscitation strategies for people with ruptured AAA. The Cochrane Vascular Information Specialist searched the Specialised Register (April 2016) and the Cochrane Register of Studies (CENTRAL (2016, Issue 3)). Clinical trials databases were searched (April 2016) for details of ongoing or unpublished studies. We sought all published and unpublished randomised controlled trial (RCTs) that compared controlled hypotension and normotensive resuscitation strategies for the management of shock in patients with ruptured abdominal aortic aneurysms. Two review authors independently assessed identified studies for potential inclusion in the review. We used standard methodological procedures in accordance with the Cochrane Handbook for Systematic Review of Interventions. We identified no RCTs that met the inclusion criteria. We found no RCTs that compared controlled hypotension and normotensive resuscitation strategies in the management of haemorrhagic shock in patients with ruptured abdominal aortic aneurysm that assessed mortality, presence of coagulopathy, intensive care unit length of stay, and the presence of myocardial infarct and renal failure. High quality studies that evaluate the best strategy for managing haemorrhagic shock in ruptured abdominal aortic aneurysms are required.

Controlled hypotension versus normotensive resuscitation strategy for people with ruptured abdominal aortic aneurysm.

PubMed

Moreno, Daniel H; Cacione, Daniel G; Baptista-Silva, Jose Cc

2018-06-13

An abdominal aortic aneurysm (AAA) is the pathological enlargement of the aorta and can develop in both men and women. Progressive aneurysm enlargement can lead to rupture. The rupture of an AAA is frequently fatal and accounts for the death from haemorrhagic shock of at least 45 people per 100,000 population. The outcome of people with ruptured AAA varies among countries and healthcare systems, with mortality ranging from 53% to 90%. Definitive treatment for ruptured AAA includes open surgery or endovascular repair. The management of haemorrhagic shock is crucial for the person's outcome and aims to restore organ perfusion and systolic blood pressure above 100 mmHg through immediate and aggressive fluid replacement. This rapid fluid replacement is known as the normotensive resuscitation strategy. However, evidence suggests that infusing large volumes of cold fluid causes dilutional and hypothermic coagulopathy. The association of these factors may exacerbate bleeding, resulting in a 'lethal triad' of hypothermia, acidaemia, and coagulopathy. An alternative to the normotensive resuscitation strategy is the controlled (permissive) hypotension resuscitation strategy, with a target systolic blood pressure of 50 mmHg to 100 mmHg. The principle of controlled or hypotensive resuscitation has been used in some management protocols for endovascular repair of ruptured AAA. It may be beneficial in preventing blood loss by avoiding the clot disruption caused by the rapid increase in systolic blood pressure; avoiding dilution of clotting factors, platelets and fibrinogen; and by avoiding the temperature decrease that inhibits enzyme activity involved in platelet and clotting factor function. This is an update of a review first published in 2016. To compare the effects of controlled (permissive) hypotension resuscitation and normotensive resuscitation strategies for people with ruptured AAA. The Cochrane Vascular Information Specialist searched the Specialised Register (August 2017), the Cochrane Register of Studies (CENTRAL (2017, Issue 7)) and EMBASE (August 2017). The Cochrane Vascular Information Specialist also searched clinical trials databases (August 2017) for details of ongoing or unpublished studies. We sought all published and unpublished randomised controlled trial (RCTs) that compared controlled hypotension and normotensive resuscitation strategies for the management of shock in patients with ruptured abdominal aortic aneurysms. Two review authors independently assessed identified studies for potential inclusion in the review. We used standard methodological procedures in accordance with the Cochrane Handbook for Systematic Review of Interventions. We identified no RCTs that met the inclusion criteria. We found no RCTs that compared controlled hypotension and normotensive resuscitation strategies in the management of haemorrhagic shock in patients with ruptured abdominal aortic aneurysm that assessed mortality, presence of coagulopathy, intensive care unit length of stay, and the presence of myocardial infarct and renal failure. High quality studies that evaluate the best strategy for managing haemorrhagic shock in ruptured abdominal aortic aneurysms are required.

Fisher Grading Scale Associated with Language Disorders in Patients with Anterior Circulation Aneurysmal Subarachnoid Hemorrhage.

PubMed

de Souza, Moysés Loiola Ponte; Vieira, Ana Cláudia C; Andrade, Gustavo; Quinino, Saul; de Fátima Leal Griz, Maria; Azevedo-Filho, Hildo R C

2015-08-01

To associate the presence of language deficits with varying scores of the Fisher grading scale in patients with subarachnoid hemorrhage in the period preceding the treatment of aneurysm in the anterior circulation, as well as to compare the scores of this scale, identifying the grades more associated with the decline of language. Database analysis of 185 preoperative evaluations of language, through the Montreal Toulouse Protocol Alpha version and verbal fluency through CERAD battery, of patients from "Hospital da Restauração" with aneurysmal subarachnoid hemorrhage, divided according to the Fisher grading scale (Fisher I, II, III, or IV) and compared with a control group of individuals considered normal. The various scores of the Fisher grading scale have different levels of language deficits, more pronounced as the amount of blood increases. Fisher III and IV scores are most associated with the decline of language. Our study made it possible to obtain information not yet available in the literature, by correlating the various scores of the Fisher grading scale with language yet in the period preceding treatment. Copyright © 2015 Elsevier Inc. All rights reserved.

Morphology parameters for intracranial aneurysm rupture risk assessment.

PubMed

Dhar, Sujan; Tremmel, Markus; Mocco, J; Kim, Minsuok; Yamamoto, Junichi; Siddiqui, Adnan H; Hopkins, L Nelson; Meng, Hui

2008-08-01

The aim of this study is to identify image-based morphological parameters that correlate with human intracranial aneurysm (IA) rupture. For 45 patients with terminal or sidewall saccular IAs (25 unruptured, 20 ruptured), three-dimensional geometries were evaluated for a range of morphological parameters. In addition to five previously studied parameters (aspect ratio, aneurysm size, ellipticity index, nonsphericity index, and undulation index), we defined three novel parameters incorporating the parent vessel geometry (vessel angle, aneurysm [inclination] angle, and [aneurysm-to-vessel] size ratio) and explored their correlation with aneurysm rupture. Parameters were analyzed with a two-tailed independent Student's t test for significance; significant parameters (P < 0.05) were further examined by multivariate logistic regression analysis. Additionally, receiver operating characteristic analyses were performed on each parameter. Statistically significant differences were found between mean values in ruptured and unruptured groups for size ratio, undulation index, nonsphericity index, ellipticity index, aneurysm angle, and aspect ratio. Logistic regression analysis further revealed that size ratio (odds ratio, 1.41; 95% confidence interval, 1.03-1.92) and undulation index (odds ratio, 1.51; 95% confidence interval, 1.08-2.11) had the strongest independent correlation with ruptured IA. From the receiver operating characteristic analysis, size ratio and aneurysm angle had the highest area under the curve values of 0.83 and 0.85, respectively. Size ratio and aneurysm angle are promising new morphological metrics for IA rupture risk assessment. Because these parameters account for vessel geometry, they may bridge the gap between morphological studies and more qualitative location-based studies.

Association between hemodynamic modifications and clinical outcome of intracranial aneurysms treated using flow diverters

NASA Astrophysics Data System (ADS)

Paliwal, Nikhil; Damiano, Robert J.; Davies, Jason M.; Siddiqui, Adnan H.; Meng, Hui

2017-03-01

Treatment of intracranial aneurysms (IAs) has been revolutionized by the advent of endovascular Flow Diverters (FDs), which disrupt blood flow within the aneurysm to induce pro-thrombotic conditions, and serves as a scaffold for endothelial ingrowth and arterial remodeling. Despite good clinical success of FDs, complications like incomplete occlusion and post-treatment rupture leading to subarachnoid hemorrhage have been reported. In silico computational fluid dynamic analysis of the pre- and post-treated geometries of IA patients can shed light on the contrasting blood hemodynamics associated with different clinical outcomes. In this study, we analyzed hemodynamic modifications in 15 IA patients treated using a single FD; 10 IAs were completely occluded (successful) and 5 were partially occluded (unsuccessful) at 12-month follow-up. An in-house virtual stenting workflow was used to recapitulate the clinical intervention on these cases, followed by CFD to obtain pre- and post-treatment hemodynamics. Bulk hemodynamic parameters showed comparable reductions in both groups with average inflow rate and aneurysmal velocity reduction of 40.3% and 52.4% in successful cases, and 34.4% and 49.2% in unsuccessful cases. There was a substantial reduction in localized parameter like vortex coreline length and Energy Loss for successful cases, 38.2% and 42.9% compared to 10.1% and 10.5% for unsuccessful cases. This suggest that for successfully treated IAs, the localized complex blood flow is disrupted more prominently by the FD as compared to unsuccessful cases. These localized hemodynamic parameters can be potentially used in prediction of treatment outcome, thus aiding the clinicians in a priori assessment of different treatment strategies.

Association between hemodynamic modifications and clinical outcome of intracranial aneurysms treated using flow diverters.

PubMed

Paliwal, Nikhil; Damiano, Robert J; Davies, Jason M; Siddiqui, Adnan H; Meng, Hui

2017-02-11

Treatment of intracranial aneurysms (IAs) has been revolutionized by the advent of endovascular Flow Diverters (FDs), which disrupt blood flow within the aneurysm to induce pro-thrombotic conditions, and serves as a scaffold for endothelial ingrowth and arterial remodeling. Despite good clinical success of FDs, complications like incomplete occlusion and post-treatment rupture leading to subarachnoid hemorrhage have been reported. In silico computational fluid dynamic analysis of the pre- and post-treated geometries of IA patients can shed light on the contrasting blood hemodynamics associated with different clinical outcomes. In this study, we analyzed hemodynamic modifications in 15 IA patients treated using a single FD; 10 IAs were completely occluded (successful) and 5 were partially occluded (unsuccessful) at 12-month follow-up. An in-house virtual stenting workflow was used to recapitulate the clinical intervention on these cases, followed by CFD to obtain pre- and post-treatment hemodynamics. Bulk hemodynamic parameters showed comparable reductions in both groups with average inflow rate and aneurysmal velocity reduction of 40.3% and 52.4% in successful cases, and 34.4% and 49.2% in unsuccessful cases. There was a substantial reduction in localized parameter like vortex coreline length and Energy Loss for successful cases, 38.2% and 42.9% compared to 10.1% and 10.5% for unsuccessful cases. This suggest that for successfully treated IAs, the localized complex blood flow is disrupted more prominently by the FD as compared to unsuccessful cases. These localized hemodynamic parameters can be potentially used in prediction of treatment outcome, thus aiding the clinicians in a priori assessment of different treatment strategies.

The LUNA aneurysm embolisation system for intracranial aneurysm treatment: short-term, mid-term and long-term clinical and angiographic results.

PubMed

Piotin, Michel; Biondi, Alessandra; Sourour, Nader; Mounayer, Charbel; Jaworski, Maciej; Mangiafico, Salvatore; Andersson, Tommy; Söderman, Michael; Goffette, Pierre; Anxionnat, René; Blanc, Raphaël

2018-04-18

Intrasaccular aneurysm flow disruption represents an emerging endovascular approach to treat intracranial aneurysms. The purpose of this study was to determine the clinical and angiographic outcomes of using the LUNA aneurysm embolisation system (AES) for treatment of intracranial aneurysms. The LUNA AES Post-Market Clinical Follow-Up study is a prospective, multicentre, single-arm study that was designed to evaluate device safety and efficacy. Bifurcation and sidewall aneurysms were included. Aneurysm occlusion was assessed using the Raymond-Roy classification scale. Disability was assessed using the Modified Rankin Scale (mRS). Morbidity was defined as mRS >2 if baseline mRS ≤2, increase in mRS of 1 or more if baseline mRS >2, or mRS >2 if aneurysm was ruptured at baseline. Clinical and angiographic follow-up was conducted at 6, 12 and 36 months. Sixty-three subjects with 64 aneurysms were enrolled. Most aneurysms were unruptured (60/63 (95.2%)); 49 were bifurcation or terminal (49/64 (76.6%)). Mean aneurysm size was 5.6±1.8 mm (range, 3.6-14.9 mm), and mean neck size was 3.8±1.0 mm (range, 1.9-8.7 mm). Though immediate postoperative adequate occlusion was low (11/63, 18%), adequate occlusion was achieved in 78.0% (46/59) and 79.2% (42/53) of the aneurysms at 12 months and 36 months, respectively. Four patients were retreated by the 12-month follow-up (4/63 (6.3%)) and three patients were retreated by the 36-month follow-up (3/63 (4.8%)). There were two major strokes (2/63 (3.2%)), one minor stroke (1/63 (1.6%)) and three incidents of intracranial haemorrhage in two subjects (2/63 (3.2%)) prior to the 12-month follow-up. There was one instance of mortality (1/63, 1.6%). Morbidity was 0% (0/63) and 1.8% (1/63) at the 12-month and 36-month follow-ups, respectively. LUNA AES is safe and effective for the treatment of bifurcation and sidewall aneurysms. ISRCTN72343080; Results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Effect of exercise on patient specific abdominal aortic aneurysm flow topology and mixing.

PubMed

Arzani, Amirhossein; Les, Andrea S; Dalman, Ronald L; Shadden, Shawn C

2014-02-01

Computational fluid dynamics modeling was used to investigate changes in blood transport topology between rest and exercise conditions in five patient-specific abdominal aortic aneurysm models. MRI was used to provide the vascular anatomy and necessary boundary conditions for simulating blood velocity and pressure fields inside each model. Finite-time Lyapunov exponent fields and associated Lagrangian coherent structures were computed from blood velocity data and were used to compare features of the transport topology between rest and exercise both mechanistically and qualitatively. A mix-norm and mix-variance measure based on fresh blood distribution throughout the aneurysm over time were implemented to quantitatively compare mixing between rest and exercise. Exercise conditions resulted in higher and more uniform mixing and reduced the overall residence time in all aneurysms. Separated regions of recirculating flow were commonly observed in rest, and these regions were either reduced or removed by attached and unidirectional flow during exercise, or replaced with regional chaotic and transiently turbulent mixing, or persisted and even extended during exercise. The main factor that dictated the change in flow topology from rest to exercise was the behavior of the jet of blood penetrating into the aneurysm during systole. Copyright © 2013 John Wiley & Sons, Ltd.

Meta-analysis of individual-patient data from EVAR-1, DREAM, OVER and ACE trials comparing outcomes of endovascular or open repair for abdominal aortic aneurysm over 5 years.

PubMed

Powell, J T; Sweeting, M J; Ulug, P; Blankensteijn, J D; Lederle, F A; Becquemin, J-P; Greenhalgh, R M

2017-02-01

The erosion of the early mortality advantage of elective endovascular aneurysm repair (EVAR) compared with open repair of abdominal aortic aneurysm remains without a satisfactory explanation. An individual-patient data meta-analysis of four multicentre randomized trials of EVAR versus open repair was conducted to a prespecified analysis plan, reporting on mortality, aneurysm-related mortality and reintervention. The analysis included 2783 patients, with 14 245 person-years of follow-up (median 5·5 years). Early (0-6 months after randomization) mortality was lower in the EVAR groups (46 of 1393 versus 73 of 1390 deaths; pooled hazard ratio 0·61, 95 per cent c.i. 0·42 to 0·89; P = 0·010), primarily because 30-day operative mortality was lower in the EVAR groups (16 deaths versus 40 for open repair; pooled odds ratio 0·40, 95 per cent c.i. 0·22 to 0·74). Later (within 3 years) the survival curves converged, remaining converged to 8 years. Beyond 3 years, aneurysm-related mortality was significantly higher in the EVAR groups (19 deaths versus 3 for open repair; pooled hazard ratio 5·16, 1·49 to 17·89; P = 0·010). Patients with moderate renal dysfunction or previous coronary artery disease had no early survival advantage under EVAR. Those with peripheral artery disease had lower mortality under open repair (39 deaths versus 62 for EVAR; P = 0·022) in the period from 6 months to 4 years after randomization. The early survival advantage in the EVAR group, and its subsequent erosion, were confirmed. Over 5 years, patients of marginal fitness had no early survival advantage from EVAR compared with open repair. Aneurysm-related mortality and patients with low ankle : brachial pressure index contributed to the erosion of the early survival advantage for the EVAR group. Trial registration numbers: EVAR-1, ISRCTN55703451; DREAM (Dutch Randomized Endovascular Aneurysm Management), NCT00421330; ACE (Anévrysme de l'aorte abdominale, Chirurgie versus Endoprothèse), NCT00224718; OVER (Open Versus Endovascular Repair Trial for Abdominal Aortic Aneurysms), NCT00094575. © 2017 The Authors. BJS published by John Wiley & Sons Ltd on behalf of BJS Society Ltd.

18F-FDG uptake assessed by PET/CT in abdominal aortic aneurysms is associated with cellular and molecular alterations prefacing wall deterioration and rupture.

PubMed

Courtois, Audrey; Nusgens, Betty V; Hustinx, Roland; Namur, Gauthier; Gomez, Pierre; Somja, Joan; Defraigne, Jean-Olivier; Delvenne, Philippe; Michel, Jean-Baptiste; Colige, Alain C; Sakalihasan, Natzi

2013-10-01

Rupture of abdominal aortic aneurysms (AAAs) leads to a significant morbidity and mortality in aging populations, and its prediction would be most beneficial to public health. Spots positive for uptake of (18)F-FDG detected by PET are found in 12% of AAA patients (PET+), who are most often symptomatic and at high rupture risk. Comparing the (18)F-FDG-positive site with a negative site from the same aneurysm and with samples collected from AAA patients with no (18)F-FDG uptake should allow the discrimination of biologic alterations that would help in identifying markers predictive of rupture. Biopsies of the AAA wall were obtained from patients with no (18)F-FDG uptake (PET0, n = 10) and from PET+ patients (n = 8), both at the site positive for uptake and at a distant negative site of the aneurysmal wall. Samples were analyzed by immunohistochemistry, quantitative real-time polymerase chain reaction, and zymography. The sites of the aneurysmal wall with a positive (18)F-FDG uptake were characterized by a strikingly increased number of adventitial inflammatory cells, highly proliferative, and by a drastic reduction of smooth muscle cells (SMCs) in the media as compared with their negative counterpart and with the PET0 wall. The expression of a series of genes involved in the maintenance and remodeling of the wall was significantly modified in the negative sites of PET+, compared with the PET0 wall, suggesting a systemic alteration of the aneurysmal wall. Furthermore, a striking increase of several matrix metalloproteinases (MMPs), notably the MMP1 and MMP13 collagenases, was observed in the positive sites, mainly in the adventitia. Moreover, PET+ patients were characterized by a higher circulating C-reactive protein. Positive (18)F-FDG uptake in the aneurysmal wall is associated with an active inflammatory process characterized by a dense infiltrate of proliferating leukocytes in the adventitia and an increased circulating C-reactive protein. Moreover, a loss of SMC in the media and alterations of the expression of genes involved in the remodeling of adventitia and collagen degradation potentially participate in the weakening of the aneurysmal wall preceding rupture.

Implementation of visual data mining for unsteady blood flow field in an aortic aneurysm.

PubMed

Morizawa, Seiichiro; Shimoyama, Koji; Obayashi, Shigeru; Funamoto, Kenichi; Hayase, Toshiyuki

2011-12-01

This study was performed to determine the relations between the features of wall shear stress and aneurysm rupture. For this purpose, visual data mining was performed in unsteady blood flow simulation data for an aortic aneurysm. The time-series data of wall shear stress given at each grid point were converted to spatial and temporal indices, and the grid points were sorted using a self-organizing map based on the similarity of these indices. Next, the results of cluster analysis were mapped onto the real space of the aortic aneurysm to specify the regions that may lead to aneurysm rupture. With reference to previous reports regarding aneurysm rupture, the visual data mining suggested specific hemodynamic features that cause aneurysm rupture. GRAPHICAL ABSTRACT:

Heroin Use Is Associated with Ruptured Saccular Aneurysms.

PubMed

Can, Anil; Castro, Victor M; Ozdemir, Yildirim H; Dagen, Sarajune; Dligach, Dmitriy; Finan, Sean; Yu, Sheng; Gainer, Vivian; Shadick, Nancy A; Savova, Guergana; Murphy, Shawn; Cai, Tianxi; Weiss, Scott T; Du, Rose

2017-11-04

While cocaine use is thought to be associated with aneurysmal rupture, it is not known whether heroin use increases the risk of rupture in patients with non-mycotic saccular aneurysms. Our goal was to investigate the association between heroin and cocaine use and the rupture of saccular non-mycotic aneurysms. The medical records of 4701 patients with 6411 intracranial aneurysms, including 1201 prospective patients, diagnosed at the Brigham and Women's Hospital and Massachusetts General Hospital between 1990 and 2016 were reviewed and analyzed. Patients were separated into ruptured and non-ruptured groups. Univariable and multivariable logistic regression analyses were performed to determine the association between heroin, cocaine, and methadone use and the presence of ruptured intracranial aneurysms. In multivariable analysis, current heroin use was significantly associated with rupture status (OR 3.23, 95% CI 1.33-7.83) whereas former heroin use (with and without methadone replacement therapy), and current and former cocaine use were not significantly associated with intracranial aneurysm rupture. In the present study, heroin rather than cocaine use is significantly associated with intracranial aneurysm rupture in patients with non-mycotic saccular cerebral aneurysms, emphasizing the possible role of heroin in the pathophysiology of aneurysm rupture and the importance of heroin cessation in patients harboring unruptured intracranial aneurysms.

Anatomical Reproducibility of a Head Model Molded by a Three-dimensional Printer

PubMed Central

KONDO, Kosuke; NEMOTO, Masaaki; MASUDA, Hiroyuki; OKONOGI, Shinichi; NOMOTO, Jun; HARADA, Naoyuki; SUGO, Nobuo; MIYAZAKI, Chikao

We prepared rapid prototyping models of heads with unruptured cerebral aneurysm based on image data of computed tomography angiography (CTA) using a three-dimensional (3D) printer. The objective of this study was to evaluate the anatomical reproducibility and accuracy of these models by comparison with the CTA images on a monitor. The subjects were 22 patients with unruptured cerebral aneurysm who underwent preoperative CTA. Reproducibility of the microsurgical anatomy of skull bone and arteries, the length and thickness of the main arteries, and the size of cerebral aneurysm were compared between the CTA image and rapid prototyping model. The microsurgical anatomy and arteries were favorably reproduced, apart from a few minute regions, in the rapid prototyping models. No significant difference was noted in the measured lengths of the main arteries between the CTA image and rapid prototyping model, but errors were noted in their thickness (p < 0.001). A significant difference was also noted in the longitudinal diameter of the cerebral aneurysm (p < 0.01). Regarding the CTA image as the gold standard, reproducibility of the microsurgical anatomy of skull bone and main arteries was favorable in the rapid prototyping models prepared using a 3D printer. It was concluded that these models are useful tools for neurosurgical simulation. The thickness of the main arteries and size of cerebral aneurysm should be comprehensively judged including other neuroimaging in consideration of errors. PMID:26119896

Unilateral subfrontal approach to anterior communicating artery aneurysms: A review of 28 patients

PubMed Central

Petraglia, Anthony L.; Srinivasan, Vasisht; Moravan, Michael J.; Coriddi, Michelle; Jahromi, Babak S.; Vates, G Edward; Maurer, Paul K.

2011-01-01

Background: The pterional approach is the most common for AComm aneurysms, but we present a unilateral approach to a midline region for addressing the AComm complex. The pure subfrontal approach eliminates the lateral anatomic dissection requirements without sacrificing exposure. The subfrontal approach is not favored in the US compared to Asia and Europe. We describe our experience with the subfrontal approach for AComm aneurysms treated at a single institution. Methods: We identified 28 patients treated for AComm aneurysms through the subfrontal approach. Patient records and imaging studies were reviewed. Demographics and case data, as well as clinical outcome at 6 weeks and 1 year were collected. Results: Mean patient age was 48 (range 21–75) years and 64% suffered subarachnoid hemorrhage (SAH). All aneurysms were successfully clipped. Gyrus rectus was resected in 57% of cases, more commonly in ruptured cases. Intraoperative rupture occurred in 11% of cases. The average operative time was 171 minutes. There were two patient deaths. Ninety-two percent of patients had a Glasgow Outcome Scale (GOS) of 5 at 6 weeks. All unruptured patients had a GOS of 5. At 12 months, 96% of all patients had a GOS of 5. Conclusions: The subfrontal approach provides an efficient avenue to the AComm region, which reduces opening and closing friction but still yields a comprehensive operative window for access to the anterior communicating region. PMID:22059119

3D printing of intracranial aneurysm based on intracranial digital subtraction angiography and its clinical application.

PubMed

Wang, Jian-Li; Yuan, Zi-Gang; Qian, Guo-Liang; Bao, Wu-Qiao; Jin, Guo-Liang

2018-06-01

The study aimed to develop simulation models including intracranial aneurysmal and parent vessel geometries, as well as vascular branches, through 3D printing technology. The simulation models focused on the benefits of aneurysmal treatments and clinical education. This prospective study included 13 consecutive patients who suffered from intracranial aneurysms confirmed by digital subtraction angiography (DSA) in the Neurosurgery Department of Shaoxing People's Hospital. The original 3D-DSA image data were extracted through the picture archiving and communication system and imported into Mimics. After reconstructing and transforming to Binary STL format, the simulation models of the hollow vascular tree were printed using 3D devices. The intracranial aneurysm 3D printing simulation model was developed based on DSA to assist neurosurgeons in aneurysmal treatments and residency training. Seven neurosurgical residents and 15 standardization training residents received their simulation model training and gave high assessments for the educational course with the follow-up qualitative questionnaire. 3D printed simulation models based on DSA can perfectly reveal target aneurysms and help neurosurgeons select therapeutic strategies precisely. As an educational tool, the 3D aneurysm vascular simulation model is useful for training residents.

Correlation between Hemodynamics and Treatment Outcome of Intracranial Aneurysms after Intervention with Flow Diverters

NASA Astrophysics Data System (ADS)

Paliwal, Nikhil; Damiano, Robert; Davies, Jason; Siddiqui, Adnan; Meng, Hui

2015-11-01

Endovascular intervention by Flow Diverter (FD) - a densely woven stent - occludes an aneurysm by inducing thrombosis in the aneurysm sac and reconstructing the vessel. Hemodynamics plays a vital role in the thrombotic occlusion of aneurysms and eventual treatment outcome. CFD analysis of pre- and post-treatment aneurysms not only provides insight of flow modifications by FD, but also allows investigation of interventional strategies and prediction of their outcome. In this study 80 patient-specific aneurysms treated with FDs were retrospectively studied to evaluate the effect of intervention. Out of these cases, 16 required retreatment and thus are considered as having unfavorable outcome. Clinical FD deployment in these cases was simulated using an efficient virtual stenting workflow. CFD analysis was carried out on both pre- and post-treatment cases, and changes in hemodynamic parameters were calculated. Support vector machine algorithm was used to correlate the hemodynamic changes with outcome. Results show that cases having higher flow reduction into the aneurysmal sac have a better likelihood of occlusion. This suggests that changes in hemodynamics can be potentially used to predict the outcome of different clinical intervention strategies in aneurysms. This work was supported by the National Institutes of Health (R01 NS091075).

Application of Dynamic Mode Decomposition: Temporal Evolution of Flow Structures in an Aneurysm

NASA Astrophysics Data System (ADS)

Conlin, William; Yu, Paulo; Durgesh, Vibhav

2017-11-01

An aneurysm is an enlargement of a weakened arterial wall that can be fatal or debilitating on rupture. Aneurysm hemodynamics is integral to developing an understanding of aneurysm formation, growth, and rupture. The flow in an aneurysm exhibits complex fluid dynamics behavior due to an inherent unsteady inflow condition and its interactions with large-scale flow structures present in the aneurysm. The objective of this study is to identify the large-scale structures in the aneurysm, study temporal behavior, and quantify their interaction with the inflow condition. For this purpose, detailed Particle Image Velocimetry (PIV) measurements were performed at the center plane of an idealized aneurysm model for a range of inflow conditions. Inflow conditions were precisely controlled using a ViVitro SuperPump system. Dynamic Modal Decomposition (DMD) of the velocity field was used to identify coherent structures and their temporal behavior. DMD was successful in capturing the large-scale flow structures and their temporal behavior. A low dimensional approximation to the flow field was obtained with the most relevant dynamic modes and was used to obtain temporal information about the coherent structures and their interaction with the inflow, formation, evolution, and growth.

A Preliminary Observational Study of Anovulatory Uterine Bleeding After Aneurysmal Subarachnoid Hemorrhage.

PubMed

Brown, Suzanne M; Fifield, Susan W; Pizzi, Michael A; Alejos, David; Richie, Alexa N; Dinh, Tri A; Cheshire, William P; Meek, Shon E; Freeman, William D

2017-12-01

It was observed that women with aneurysmal subarachnoid hemorrhage (aSAH) tended to have earlier menses than a typical 21- to 28-day cycle. The goal was to determine whether there is an association between aSAH and early onset of menses. All cases of aSAH in women aged 18 to 55 years who were admitted to our facility's neuroscience intensive care unit from June 1, 2011, to June 30, 2012, were reviewed. The electronic healthcare record for each of these patients was examined for documentation of menses onset, computed tomography of the head, brain aneurysm characteristics, modified Fisher score and Glasgow Coma Scale on admission, presence/absence of vasospasm, medical/surgical history, and use of medications that affect the menstrual cycle. The mean onset of menses in this study population was compared with the mean of 21 to 28 days with the 1-sample t test. During the study period, 103 patients with subarachnoid hemorrhage were admitted. Sixty-one were women, and 15 were aged 18 to 55 years. Nine of the 15 (60%) had documentation of menses occurring during their initial week of hospitalization; 1 patient had documentation of menses on hospital day 12. There is a significant difference when the mean onset of menses in our patient population is compared with the approximate normal menstrual cycle of 21 to 28 days (P < .01). Early onset of menses or abnormal uterine bleeding after SAH may occur in women with aSAH and typically within the first 7 to 10 days after intracranial aneurysm rupture. The physiologic cause of early onset of menses after aSAH, whether primary or secondary, remains unknown.

Endovascular repair or open repair for ruptured abdominal aortic aneurysm: a Cochrane systematic review

PubMed Central

Badger, S A; Harkin, D W; Blair, P H; Ellis, P K; Kee, F; Forster, R

2016-01-01

Objectives Emergency endovascular aneurysm repair (eEVAR) may improve outcomes for patients with ruptured abdominal aortic aneurysm (RAAA). The study aim was to compare the outcomes for eEVAR with conventional open surgical repair for the treatment of RAAA. Setting A systematic review of relevant publications was performed. Randomised controlled trials (RCTs) comparing eEVAR with open surgical repair for RAAA were included. Participants 3 RCTs were included, with a total of 761 patients with RAAA. Interventions Meta-analysis was performed with fixed-effects models with ORs and 95% CIs for dichotomous data and mean differences with 95% CIs for continuous data. Primary and secondary outcome measures Primary outcome was short-term mortality. Secondary outcome measures included aneurysm-specific and general complication rates, quality of life and economic analysis. Results Overall risk of bias was low. There was no difference between the 2 interventions on 30-day (or in-hospital) mortality, OR 0.91 (95% CI 0.67 to 1.22; p=0.52). 30-day complications included myocardial infarction, stroke, composite cardiac complications, renal complications, severe bowel ischaemia, spinal cord ischaemia, reoperation, amputation and respiratory failure. Reporting was incomplete, and no robust conclusion was drawn. For complication outcomes that did include at least 2 studies in the meta-analysis, there was no clear evidence to support a difference between eEVAR and open repair. Longer term outcomes and cost per patient were evaluated in only a single study, thus precluding definite conclusions. Conclusions Outcomes between eEVAR and open repair, specifically 30-day mortality, are similar. However, further high-quality trials are required, as the paucity of data currently limits the conclusions. PMID:26873043

The impact of endovascular aneurysm repair on mortality for elective abdominal aortic aneurysm repair in England and the United States.

PubMed

Karthikesalingam, Alan; Holt, Peter J; Vidal-Diez, Alberto; Bahia, Sandeep S; Patterson, Benjamin O; Hinchliffe, Robert J; Thompson, Matthew M

2016-08-01

Procedural mortality is of paramount importance for patients undergoing elective abdominal aortic aneurysm (AAA) repair. Previous comparative studies have demonstrated international differences in the care of ruptured AAA. This study compared the use of endovascular aneurysm repair (EVAR) and in-hospital mortality for elective AAA repair in England and the United States. The English Hospital Episode Statistics and the U.S. Nationwide Inpatient Sample (NIS) were interrogated for elective AAA repair from 2005 to 2010. In-hospital mortality and the use of EVAR were analyzed separately for each health care system, after within-country risk adjustment for age, gender, year, and an accepted national comorbidity index. The study included 21,272 patients with AAA in England, of whom 86.61% were male, with median (interquartile range) age of 74 (69-79) years. There were 196,113 AAA patients in the United States, of whom 76.14% were male, with median (interquartile range) age of 73 (67-78) years. In-hospital mortality was greater in England (4.09% vs 1.96 %; P < .01) and EVAR less common (37.33% vs 64.36%; P < .01). These observations persisted in age- and gender-matched comparison. In both countries, lower mortality and greater use of EVAR were seen in centers performing greater numbers of AAA repairs per annum. In England, lower mortality and greater use of EVAR were seen in teaching hospitals with larger bed capacity. In-hospital survival and the uptake of EVAR are lower in England than in the United States. In both countries, mortality was lowest in high-caseload centers performing a greater proportion of cases with endovascular repair. These common factors suggest strategies for improving outcomes for patients requiring elective AAA repair. Copyright © 2016. Published by Elsevier Inc.

Prevalence of extracranial carotid artery aneurysms in patients with an intracranial aneurysm.

PubMed

Pourier, V E C; van Laarhoven, C J H C M; Vergouwen, M D I; Rinkel, G J E; de Borst, Gert J

2017-01-01

Aneurysms in various arterial beds have common risk- and genetic factors. Data on the correlation of extracranial carotid artery aneurysms (ECAA) with aneurysms in other vascular territories are lacking. We aimed to investigate the prevalence of ECAA in patients with an intracranial aneurysm (IA). We used prospectively collected databases of consecutive patients registered at the University Medical Center Utrecht with an unruptured intracranial aneurysm (UIA) or aneurysmal Subarachnoid hemorrhage (SAH). The medical files of patients included in both databases were screened for availability of radiological reports, imaging of the brain and of the cervical carotid arteries. All available radiological images were then reviewed primarily for the presence of an ECAA and secondarily for an extradural/cavernous carotid or vertebral artery aneurysm. An ECAA was defined as a fusiform dilation ≥150% of the normal internal or common carotid artery or a saccular distention of any size. We screened 4465 patient records (SAH database n = 3416, UIA database n = 1049), of which 2931 had radiological images of the carotid arteries available. An ECAA was identified in 12/638 patients (1.9%; 95% CI 1.1-3.3) with completely imaged carotid arteries and in 15/2293 patients (0.7%; 95% CI 0.4-1.1) with partially depicted carotid arteries. Seven out of 27 patients had an additional extradural (cavernous or vertebral artery) aneurysm. This comprehensive study suggests a prevalence for ECAA of approximately 2% of patients with an IA. The rarity of the disease makes screening unnecessary so far. Future registry studies should study the factors associated with IA and ECAA to estimate the prevalence of ECAA in these young patients more accurately.

Long term follow-up of bifurcation aneurysms treated with braided stent assisted coiling and complex T- and Y- stent constructs.

PubMed

Cheung, Nicholas K; Chiu, Albert Hy; Cheung, Andrew; Wenderoth, Jason D

2018-06-01

Stent assisted coil embolization (SACE) of bifurcation aneurysms is challenging. Heterogeneous results have been achieved to date, but largely for laser cut stents. While braided stents offer multiple technical advantages, their long term efficacy has yet to be validated. To report the first long term 18 month results for the durability of bifurcation aneurysms treated with braided stents. Over a 4 year period, 59 consecutive patients with 60 bifurcation aneurysms underwent elective braided SACE across three Australian neurovascular centers. 17 of these aneurysms underwent T- or Y-shaped stent constructs. All patients had immediate, 6 month and 18 month clinical and radiological follow-up. Radiological assessment was made on modified Raymond-Roy occlusion scores while clinical assessment was based on the modified Rankin Scale. Subgroup analysis of 17 aneurysms treated with multi-stent constructs was conducted. 6 month follow-up data were available for 59 aneurysms and 18 month follow-up data for 58 aneurysms. Satisfactory aneurysm occlusion was achieved in 97% at inception and at 6 months, and 98% at 18 months. Good neurological outcomes were achieved in 95% at 18 months. Similar satisfactory results were achieved with the multi-stent construct cohort. Intraprocedural thromboembolic events were recorded in 5% and delayed events in 2%. Technical complications were found in 5%. All complication rate was 13%. Braided SACE was safe, efficacious, and durable at the long term 18 month follow-up, including for multi-stent constructs. Preliminary results indicate favorable clinical and radiological outcomes compared with laser cut stents. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The clinical value of MRA at 3.0 T for the diagnosis and therapeutic planning of patients with subarachnoid haemorrhage.

PubMed

Chen, Yuan-Chang; Sun, Zhen-Kui; Li, Ming-Hua; Li, Yong-Dong; Wang, Wu; Tan, Hua-Qiao; Gu, Bin-Xian; Chen, Shi-Wen

2012-07-01

To evaluate the clinical value of unenhanced magnetic resonance angiography (MRA) at 3.0 T for the diagnosis and therapeutic planning of patients with subarachnoid haemorrhage (SAH). A total of 165 patients with SAH were referred for three-dimensional time-of-flight MRA (3D-TOF-MRA) before digital subtraction angiography (DSA). For each aneurysm, 3D-TOF-MRA was used to determine whether the aneurysm was suitable for coil placement with or without balloon/stent-assisted coiling, surgical clipping or conservative treatment. Treatment planning with 3D-TOF-MRA was compared with actual treatment decisions or treatment that had been carried out in each aneurysm decided using DSA. The aneurysm-based evaluation yielded accuracy of 96.9%, sensitivity of 97.6%, specificity of 93.1%, positive predictive value (PPV) of 98.8% and negative predictive value (NPV) of 87.1%, in the detection of intracranial aneurysms. Treatment planning could be correctly made on the basis of aneurysm anatomy and working view by volume rendering (VR) 3D-TOF-MRA with accuracy, sensitivity, specificity, PPV and NPV of 94.9%, 94.0%, 100%, 100% and 74.4%, respectively, on a per aneurysm-based evaluation. VR 3D-TOF-MRA offers high diagnostic accuracy in the detection of ruptured intracranial aneurysms, and appears to be an effective treatment planning tool for most patients with SAH. VR 3D-TOF-MRA offers high diagnostic accuracy for detecting ruptured intracranial aneurysms. • VR 3D-TOF-MRA helps treatment planning for patients with subarachnoid haemorrhage. • 3D-TOF-MRA is non-invasive and avoids using ionising radiation or contrast agents.

Optical coherence tomography assessment of vessel wall degradation in aneurysmatic thoracic aortas

NASA Astrophysics Data System (ADS)

Real, Eusebio; Eguizabal, Alma; Pontón, Alejandro; Val-Bernal, J. Fernando; Mayorga, Marta; Revuelta, José M.; López-Higuera, José; Conde, Olga M.

2013-06-01

Optical coherence tomographic images of ascending thoracic human aortas from aneurysms exhibit disorders on the smooth muscle cell structure of the media layer of the aortic vessel as well as elastin degradation. Ex-vivo measurements of human samples provide results that correlate with pathologist diagnosis in aneurysmatic and control aortas. The observed disorders are studied as possible hallmarks for aneurysm diagnosis. To this end, the backscattering profile along the vessel thickness has been evaluated by fitting its decay against two different models, a third order polynomial fitting and an exponential fitting. The discontinuities present on the vessel wall on aneurysmatic aortas are slightly better identified with the exponential approach. Aneurysmatic aortic walls present uneven reflectivity decay when compared with healthy vessels. The fitting error has revealed as the most favorable indicator for aneurysm diagnosis as it provides a measure of how uniform is the decay along the vessel thickness.

The interactions between bloodstream and vascular structure on aortic dissecting aneurysmal model: A numerical study

NASA Astrophysics Data System (ADS)

Chen, Zeng-Sheng; Fan, Zhan-Ming; Zhang, Xi-Wen

2013-06-01

Stent-graft implantation is an important means of clinical treatment for aortic dissecting aneurysm (ADA). However, researches on fluid dynamics effects of stent were rare. Computer simulation was used to investigate the interactions between bloodstream and vascular structure in a stented ADA, which endures the periodic pulse velocity and pressure. We obtained and analyzed the flow velocity distribution, the wall displacement and wall stress in the ADA. By comparing the different results between a non-stented and a stented ADA, we found that the insertion of a vascular graft can make the location of maximum stress and displacement move from the aneurysm lumen wall to the artery wall, accompanied with a greatly decrease in value. These results imply that the placement of a stent-graft of any kind to occlude ADA will result in a decreased chance of rupture.

Genetics of the extracellular matrix in aortic aneurysmal diseases.

PubMed

Lin, Chien-Jung; Lin, Chieh-Yu; Stitziel, Nathan O

2018-04-12

Aortic aneurysms are morbid conditions that can lead to rupture or dissection and are categorized as thoracic (TAA) or abdominal aortic aneurysms (AAA) depending on their location. While AAA shares overlapping risk factors with atherosclerotic cardiovascular disease, TAA exhibits strong heritability. Human genetic studies in the past two decades have successfully identified numerous genes involved in both familial and sporadic forms of aortic aneurysm. In this review we will discuss the genetic basis of aortic aneurysm, focusing on the extracellular matrix and how insights from these studies have informed our understanding of human biology and disease pathogenesis. Copyright © 2017 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.

Aneurysm treatment practice patterns for newly appointed dual-trained cerebrovascular/endovascular neurosurgeons: Comparison of open surgical to neuroendovascular procedures in the first 2 years of academic practice

PubMed Central

Jiang, Bowen; Bender, Matthew T.; Hasjim, Bima; Hsu, Frank P. K.; Tamargo, Rafael J.; Huang, Judy; Colby, Geoffrey P.; Coon, Alexander L.; Lin, Li-Mei

2017-01-01

Background: The practice patterns of a hybrid open cerebrovascular/neuroendovascular (CVNV) neurosurgeon in early academic practice is unknown. Methods: We performed a multi-institutional retrospective cohort study of patients with cerebral aneurysms that were treated within the first 24 months of the neurosurgeon’s practice. Results: A total of 533 aneurysms were treated by the three senior authors within the first 24 months of their academic practice. Of these aneurysms, 172 were treated with microsurgical clipping, 191 with coiling, and 170 with flow diversion. Treatment in the setting of acute subarachnoid hemorrhage (SAH) occurred in 23% (122/533) of the aneurysms. Majority of the clipped aneurysms (70%, 121/172) were anterior cerebral artery (ACA), anterior communicating artery (ACOM), or middle cerebral artery (MCA) in location. In comparison, only 23% (82/361) of aneurysms treated with coiling or flow diversion therapy were ACA, ACOM, or MCA in location (P < 0.05). Additionally, majority of the flow diverted aneurysm (65%, 111/170) were cavernous or ophthalmic/paraophthalmic in location. During the second year of practice, there appeared to be a trend towards more aneurysms treated with neuroendovascular techniques (22% increase), particularly in flow diversion. Conclusion: Although the CVNV neurosurgeon treats cerebral aneurysms more commonly with neuroendovascular techniques, a third of the cerebral aneurysms are still selected for microsurgical clipping. Aneurysms located along the ACA/ACOM or MCA are the most frequent aneurysms reserved for microsurgical clipping. The CVNV neurosurgeon must be prepared to manage a high percentage of ACA/ACOM or MCA aneurysms microsurgically. PMID:28808603

International trends in patient selection for elective endovascular aneurysm repair: sicker patients with safer anatomy leading to improved 1-year survival.

PubMed

Fitridge, Robert A; Boult, Margaret; Mackillop, Clare; De Loryn, Tania; Barnes, Mary; Cowled, Prue; Thompson, Matthew M; Holt, Peter J; Karthikesalingam, Alan; Sayers, Robert D; Choke, Edward; Boyle, Jonathan R; Forbes, Thomas L; Novick, Teresa V

2015-02-01

To review the trends in patient selection and early death rate for patients undergoing elective endovascular repair of infrarenal abdominal aortic aneurysms (EVAR) in 3 countries. For this study, audit data from 4,163 patients who had undergone elective infrarenal EVAR were amalgamated. The data originated from Australia, Canada (Ontario), and England (London, Cambridge, and Leicester). Statistical analyses were undertaken to determine whether patient characteristics and early death rate varied between and within study groups and over time. The study design was retrospective analysis of data collected prospectively between 1999 and 2012. One-year survival improved over time (P = 0.0013). Canadian patients were sicker than those in Australia or England (P < 0.001). American Society of Anesthesiologists classification (ASA) increased over time across all countries although more significantly in Canada. Age at operation remained constant, although older patients were treated more recently in London (P < 0.001). English centers treated larger aneurysms compared with Australia and Canada (P < 0.001). Australian centers treated a much larger proportion of aneurysms that were <55 mm than other countries. Preoperative creatinine levels decreased over time for all countries and centers (P < 0.001). Infrarenal neck angles have significantly decreased over time (P < 0.001). Recent data from London (UK) showed that operations were performed on longer (P < 0.001) and wider (P < 0.001) infrarenal necks than elsewhere. In this international comparison, several trends were noted including improved 1-year survival despite declining patient health (as measured by increasing ASA status). This may reflect greater knowledge regarding EVAR that centers from different countries have gained over the last decade and improved medical management of patients with aneurysmal disease. Copyright © 2015 Elsevier Inc. All rights reserved.

Lipoprotein (a): a potential biological marker for unruptured intracranial aneurysms.

PubMed

Phillips, J; Roberts, G; Bolger, C; el Baghdady, A; Bouchier-Hayes, D; Farrell, M; Collins, P

1997-05-01

The diagnosis and treatment of intracranial aneurysms (IAs) prior to rupture reduces the high morbidity and mortality associated with their occurrence. Elevated serum lipoprotein (a) [Lp(a)] level, an independent risk factor for atherogenesis, has been demonstrated in sporadic IA disease (1). The purpose of this study was to assess the degree of correlation between elevated Lp(a) levels and the occurrence of IAs in asymptomatic first degree relatives of index cases from three families exhibiting a familial tendency towards IA development. 25 family members and 41 healthy controls were screened by random serum Lp(a) sampling. All family members received 4-vessel cerebral angiography. Eleven family members were found on angiography to harbour asymptomatic aneurysms and all were successfully treated by surgery. Of these 11, ten had significantly raised serum Lp(a) levels (> 30 mg%). Fourteen family members had negative angiograms. Eight of this latter group, mean age 43.6 +/- 3.8 years, had serum Lp(a) levels above the normal range. Mean Lp(a) levels were 53.7 +/- 1.2 mg% in subjects with aneurysms compared with 22.1 +/- 1.45 mg% in subjects without demonstrable aneurysms and 10.5 +/- 0.48 mg% in the control population. The prevalence of elevated Lp(a) levels in these families and the high degree of association of raised Lp(a) levels with the presence of IAs in several family members warrants follow up of angiographically negative young subjects. We require a case-control study to establish whether particular polymorphisms at the apoprotein (a) gene level are associated with the occurrence of IAs in these families.

Cavernous carotid aneurysms in the era of flow diversion: a need to revisit treatment paradigms.

PubMed

Tanweer, O; Raz, E; Brunswick, A; Zumofen, D; Shapiro, M; Riina, H A; Fouladvand, M; Becske, T; Nelson, P K

2014-12-01

Recent techniques of endoluminal reconstruction with flow-diverting stents have not been incorporated into treatment algorithms for cavernous carotid aneurysms. This study examines the authors' institutional experience and a systematic review of the literature for outcomes and complications using the Pipeline Embolization Device in unruptured cavernous carotid aneurysms. A retrospective search for cavernous carotid aneurysms from a prospectively collected data base of aneurysms treated with the Pipeline Embolization Device at our institution was performed. Baseline demographic, clinical, and laboratory values; intrainterventional data; and data at all follow-up visits were collected. A systematic review of the literature for complication data was performed with inquiries sent when clarification of data was needed. Forty-three cavernous carotid aneurysms were included in the study. Our mean radiographic follow-up was 2.05 years. On last follow-up, 88.4% of the aneurysms treated had complete or near-complete occlusion. Aneurysm complete or near-complete occlusion rates at 6 months, 12 months, and 36 months were 81.4%, 89.7%, and 100%, respectively. Of patients with neuro-ophthalmologic deficits on presentation, 84.2% had improvement in their visual symptoms. Overall, we had a 0% mortality rate and a 2.3% major neurologic complication rate. Our systematic review of the literature yielded 227 cavernous carotid aneurysms treated with the Pipeline Embolization Device with mortality and morbidity rates of 0.4% and 3.1%, respectively. Endoluminal reconstruction with flow diversion for large unruptured cavernous carotid aneurysms can yield high efficacy with low complications. Further long-term data will be helpful in assessing the durability of the cure; however, we advocate a revisiting of current management paradigms for cavernous carotid aneurysms. © 2014 by American Journal of Neuroradiology.

Immediate coma and poor outcome in subarachnoid haemorrhage are independently associated with an aneurysmal origin.

PubMed

Tsermoulas, Georgios; Flett, Lisa; Gregson, Barbara; Mitchell, Patrick

2013-08-01

Subarachnoid haemorrhage (SAH) may present with coma and this is known to be associated with aneurysmal origin and blood load. Aneurysmal origin is associated with increased blood load and existing data do not allow us to determine if the association between coma and aneurysmal SAH is wholly due to blood load or if aneurysmal origin has an additional independent effect. The objective of our study is to find if an aneurysmal origin is a predictor of acute onset of coma independent of blood load. A series of consecutive patients with spontaneous SAH were divided into two groups: aneurysmal (aSAH) and non-aneurysmal--angiographically negative SAH (naSAH). Blood load was quantified so that the effect of aneurysmal origin could be resolved from the effect of the amount of blood spilled. Non-parametric regression was used to relate blood load to coma and poor outcome rates for aneurysmal bleeds. We analysed a total of 421 patients presenting during the period 2009-2011. Ninety aneurysmal cases presented with coma, seventy immediately in the early phase and seven shortly after rebleeding. None of the naSAH cases presented with immediate coma and 1 developed delayed coma. Delayed coma was associated with acute hydrocephalus in both groups. Aneurysmal origin was found to be an independent determinant of immediate coma (p=0.02) and poor outcome (p<0.001). Immediate coma and poor outcome in SAH are associated with an aneurysmal origin and do not characterize naSAH. Copyright © 2013 Elsevier B.V. All rights reserved.

The minimally invasive management of visceral artery aneurysms and pseudoaneurysms.

PubMed

Fankhauser, Grant T; Stone, William M; Naidu, Sailendra G; Oderich, Gustavo S; Ricotta, Joseph J; Bjarnason, Haraldur; Money, Samuel R

2011-04-01

Minimally invasive methods (MIMs) are now available for the management of visceral artery aneurysms and pseudoaneurysms (visceral artery aneurysms [VAA]). The purpose of this study was to review our 10-year experience with the MIM of treating VAA. All patients evaluated from June 1999 to June 2009 with VAAs were reviewed. Demographics, therapy, and results were analyzed. MIM was attempted in 185 aneurysms in 176 patients. Initial intervention was successful in 98% ofaneurysms. Sixty-three (34%) aneurysms were located in the splenic artery, 56 (30%) in the hepatic, 28 (15%) in the gastroduodenal, 16 (8.6%) in the pancreaticoduodenal, six (3.2%) in the superior mesenteric, four (2.1%) in the gastric, four (2.1%) in the celiac, four (2.1%) in the gastroepiploic, two (1%) in the inferior mesenteric, and one (0.5%) in the middle colic artery. Pseudoaneurysms were more common than true aneurysms (64% vs 36%). Bleeding was the indication for intervention in 86 aneurysms (46%). Initial treatment was successful in 177 aneurysms (98%). Reintervention was required in five (3%) aneurysms within 30 days. Coiling was used alone in 139 aneurysms (75%) and in combination with at least one other technique in 20 (11%) cases. Thirty-day aneurysm-related mortality was 3.4% (six deaths). Five additional deaths occurred during 30-day follow-up, although none was related to complications of the aneurysms (2.8%). MIM for visceral artery aneurysms can be used alone or in combination to effectively treat VAAs in elective or emergent conditions. Copyright © 2011 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.

Follow-up of intracranial aneurysms treated by flow diverter: comparison of three-dimensional time-of-flight MR angiography (3D-TOF-MRA) and contrast-enhanced MR angiography (CE-MRA) sequences with digital subtraction angiography as the gold standard.

PubMed

Attali, Jonathan; Benaissa, Azzedine; Soize, Sébastien; Kadziolka, Krzysztof; Portefaix, Christophe; Pierot, Laurent

2016-01-01

Follow-up of intracranial aneurysms treated by flow diverter with MRI is complicated by imaging artifacts produced by these devices. This study compares the diagnostic accuracy of three-dimensional time-of-flight MR angiography (3D-TOF-MRA) and contrast-enhanced MRA (CE-MRA) at 3 T for the evaluation of aneurysm occlusion and parent artery patency after flow diversion treatment, with digital subtraction angiography (DSA) as the gold standard. Patients treated with flow diverters between January 2009 and January 2013 followed by MRA at 3 T (3D-TOF-MRA and CE-MRA) and DSA within a 48 h period were included in a prospective single-center study. Aneurysm occlusion was assessed with full and simplified Montreal scales and parent artery patency with three-grade and two-grade scales. Twenty-two patients harboring 23 treated aneurysms were included. Interobserver agreement using simplified scales for occlusion (Montreal) and parent artery patency were higher for DSA (0.88 and 0.61) and CE-MRA (0.74 and 0.55) than for 3D-TOF-MRA (0.51 and 0.02). Intermodality agreement was higher for CE-MRA (0.88 and 0.32) than for 3D-TOF-MRA (0.59 and 0.11). CE-MRA yielded better accuracy than 3D-TOF-MRA for aneurysm remnant detection (sensitivity 83% vs 50%; specificity 100% vs 100%) and for the status of the parent artery (specificity 63% vs 32%; sensitivity 100% vs 100%). At 3 T, CE-MRA is superior to 3D-TOF-MRA for the evaluation of aneurysm occlusion and parent artery patency after flow diversion treatment. However, intraluminal evaluation remains difficult with MRA regardless of the sequence used. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Computational fluid dynamics (CFD) using porous media modeling predicts recurrence after coiling of cerebral aneurysms.

PubMed

Umeda, Yasuyuki; Ishida, Fujimaro; Tsuji, Masanori; Furukawa, Kazuhiro; Shiba, Masato; Yasuda, Ryuta; Toma, Naoki; Sakaida, Hiroshi; Suzuki, Hidenori

2017-01-01

This study aimed to predict recurrence after coil embolization of unruptured cerebral aneurysms with computational fluid dynamics (CFD) using porous media modeling (porous media CFD). A total of 37 unruptured cerebral aneurysms treated with coiling were analyzed using follow-up angiograms, simulated CFD prior to coiling (control CFD), and porous media CFD. Coiled aneurysms were classified into stable or recurrence groups according to follow-up angiogram findings. Morphological parameters, coil packing density, and hemodynamic variables were evaluated for their correlations with aneurysmal recurrence. We also calculated residual flow volumes (RFVs), a novel hemodynamic parameter used to quantify the residual aneurysm volume after simulated coiling, which has a mean fluid domain > 1.0 cm/s. Follow-up angiograms showed 24 aneurysms in the stable group and 13 in the recurrence group. Mann-Whitney U test demonstrated that maximum size, dome volume, neck width, neck area, and coil packing density were significantly different between the two groups (P < 0.05). Among the hemodynamic parameters, aneurysms in the recurrence group had significantly larger inflow and outflow areas in the control CFD and larger RFVs in the porous media CFD. Multivariate logistic regression analyses demonstrated that RFV was the only independently significant factor (odds ratio, 1.06; 95% confidence interval, 1.01-1.11; P = 0.016). The study findings suggest that RFV collected under porous media modeling predicts the recurrence of coiled aneurysms.

The safety of vasopressor-induced hypertension in subarachnoid hemorrhage patients with coexisting unruptured, unprotected intracranial aneurysms.

PubMed

Reynolds, Matthew R; Buckley, Robert T; Indrakanti, Santoshi S; Turkmani, Ali H; Oh, Gerald; Crobeddu, Emanuela; Fargen, Kyle M; El Ahmadieh, Tarek Y; Naidech, Andrew M; Amin-Hanjani, Sepideh; Lanzino, Giuseppe; Hoh, Brian L; Bendok, Bernard R; Zipfel, Gregory J

2015-10-01

Vasopressor-induced hypertension (VIH) is an established treatment for patients with aneurysmal subarachnoid hemorrhage (SAH) who develop vasospasm and delayed cerebral ischemia (DCI). However, the safety of VIH in patients with coincident, unruptured, unprotected intracranial aneurysms is uncertain. This retrospective multiinstitutional study identified 1) patients with aneurysmal SAH and 1 or more unruptured, unprotected aneurysms who required VIH therapy (VIH group), and 2) patients with aneurysmal SAH and 1 or more unruptured, unprotected aneurysms who did not require VIH therapy (non-VIH group). All patients had previously undergone surgical or endovascular treatment for the presumed ruptured aneurysm. Comparisons between the VIH and non-VIH patients were made in terms of the patient characteristics, clinical and radiographic severity of SAH, total number of aneurysms, number of ruptured/unruptured aneurysms, aneurysm location/size, number of unruptured and unprotected aneurysms during VIH, severity of vasospasm, degree of hypervolemia, and degree and duration of VIH therapy. For the VIH group (n = 176), 484 aneurysms were diagnosed, 231 aneurysms were treated, and 253 unruptured aneurysms were left unprotected during 1293 total days of VIH therapy (5.12 total years of VIH therapy for unruptured, unprotected aneurysms). For the non-VIH group (n = 73), 207 aneurysms were diagnosed, 93 aneurysms were treated, and 114 unruptured aneurysms were left unprotected. For the VIH and non-VIH groups, the mean sizes of the ruptured (7.2 ± 0.3 vs 7.8 ± 0.6 mm, respectively; p = 0.27) and unruptured (3.4 ± 0.2 vs 3.2 ± 0.2 mm, respectively; p = 0.40) aneurysms did not differ. The authors observed 1 new SAH from a previously unruptured, unprotected aneurysm in each group (1 of 176 vs 1 of 73 patients; p = 0.50). Baseline patient characteristics and comorbidities were similar between groups. While the degree of hypervolemia was similar between the VIH and non-VIH patients (fluid balance over the first 10 days of therapy: 3146.2 ± 296.4 vs 2910.5 ± 450.7 ml, respectively; p = 0.67), VIH resulted in a significant increase in mean arterial pressure (mean increase over the first 10 days of therapy relative to baseline: 125.1% ± 1.0% vs 98.2% ± 1.2%, respectively; p < 0.01) and systolic blood pressure (125.6% ± 1.1% vs. 104.1% ± 5.2%, respectively; p < 0.01). For small, unruptured, unprotected intracranial aneurysms in SAH patients, the frequency of aneurysm rupture during VIH therapy is rare. The authors do not recommend withholding VIH therapy from these patients.

Impact of Aneurysm Projection on Intraoperative Complications During Surgical Clipping of Ruptured Posterior Communicating Artery Aneurysms.

PubMed

Fukuda, Hitoshi; Hayashi, Kosuke; Yoshino, Kumiko; Koyama, Takashi; Lo, Benjamin; Kurosaki, Yoshitaka; Yamagata, Sen

2016-03-01

Surgical clipping of ruptured posterior communicating artery (PCoA) aneurysms is a well-established procedure to date. However, preoperative factors associated with procedure-related risk require further elucidation. To investigate the impact of the direction of aneurysm projection on the incidence of procedure-related complications during surgical clipping of ruptured PCoA aneurysms. A total of 65 patients with ruptured PCoA aneurysms who underwent surgical clipping were retrospectively analyzed from a single-center, prospective, observational cohort database in this study. The aneurysms were categorized into lateral and posterior projection groups, depending on direction of the dome. Characteristics and operative findings of each projection group were identified. We also evaluated any correlation of aneurysm projection with the incidence of procedure-related complications. Patients with ruptured PCoA aneurysms with posterior projection more likely presented with good-admission-grade subarachnoid hemorrhage (P = .01, χ test) and were less to also have intracerebral hematoma (P = .01). These aneurysms were found to be associated with higher incidence of intraoperative rupture (P = .02), complex clipping with fenestrated clips (P = .02), and dense adherence to PCoA or its perforators (P = .04) by univariate analysis. Aneurysms with posterior projection were also correlated with procedure-related complications, including postoperative cerebral infarction or hematoma formation (odds ratio, 5.87; 95% confidence interval, 1.11-31.1; P = .04) by multivariable analysis. Ruptured PCoA aneurysms with posterior projection carried a higher risk of procedure-related complications of surgical clipping than those with lateral projection.

Minimally Invasive Thumb-sized Pterional Craniotomy for Surgical Clip Ligation of Unruptured Anterior Circulation Aneurysms.

PubMed

Deshaies, Eric M; Villwock, Mark R; Singla, Amit; Toshkezi, Gentian; Padalino, David J

2015-08-11

Less invasive surgical approaches for intracranial aneurysm clipping may reduce length of hospital stay, surgical morbidity, treatment cost, and improve patient outcomes. We present our experience with a minimally invasive pterional approach for anterior circulation aneurysms performed in a major tertiary cerebrovascular center and compare the results with an aged matched dataset from the Nationwide Inpatient Sample (NIS). From August 2008 to December 2012, 22 elective aneurysm clippings on patients ≤55 years of age were performed by the same dual fellowship-trained cerebrovascular/endovascular neurosurgeon. One patient (4.5%) experienced transient post-operative complications. 18 of 22 patients returned for follow-up imaging and there were no recurrences through an average duration of 22 months. A search in the NIS database from 2008 to 2010, also for patients aged ≤55 years of age, yielded 1,341 hospitalizations for surgical clip ligation of unruptured cerebral aneurysms. Inpatient length of stay and hospital charges at our institution using the minimally invasive thumb-sized pterional technique were nearly half that of NIS (length of stay: 3.2 vs 5.7 days; hospital charges: $52,779 vs. $101,882). The minimally invasive thumb-sized pterional craniotomy allows good exposure of unruptured small and medium-sized supraclinoid anterior circulation aneurysms. Cerebrospinal fluid drainage from key subarachnoid cisterns and constant bimanual microsurgical techniques avoid the need for retractors which can cause contusions, localized venous infarctions, and post-operative cerebral edema at the retractor sites. Utilizing this set of techniques has afforded our patients with a shorter hospital stay at a lower cost compared to the national average.

The result of surgical treatment in patients with cerebral aneurysms in Maharaj Nakorn Chiang Mai Hospital: a report of 225 cases.

PubMed

Watcharasaksilp, Wanarak; Limpastan, Kriengsak; Norasathada, Tanya; Vaniyapong, Tanat

2013-07-01

Evaluate the result of intracranial aneurysm surgery in Maharaj Nakorn Chiang Mai Hospital. A retrospective study ofpatients who underwent surgery for intracranial aneurysms between 2003 and 2007. The patients'age, gender, signs and symptoms, CT brain findings, Subarachnoid hemorrhage (SAH), World Federation of Neurosurgical Society grading (WFNS), and aneurysm location were studied and correlated with outcome after surgery. Two hundred twenty five patients ofintracranial aneurysm were operated on between 2003 and 2007. Two hundred nine patients (92%) had anterior circulation aneurysms and 18 (8%) had posterior circulation aneurysms. The outcome, as evaluated by Glasgow Outcome Scale (GOS), showed good recovery and moderate disability patients (142, 62.9%) were classified as favorable outcome group whereas patients with severe disability, vegetative state, and dead (83, 36.9%) were classified as unfavorable outcome. According to WFNS grading, the patients with unruptured aneurysm and WFNS grade 1-2 had favorable outcome in 116 patients (78.37%) and unfavorable outcome in 32 patients (21.62%). Whereas the patients with WFNS grade 3-5 had favorable outcome in 32 patients (33.76%) and unfavorable outcome in 51 patients (66.23%). This study of 225 cases revealed 142 cases with favorable outcome and 83 cases with unfavorable outcome. Factors that affected the outcome were WFNS grading and age.

Endovascular Aneurysm Repair: Is Imaging Surveillance Robust, and Does It Influence Long-term Mortality?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Waduud, Mohammed Abdul, E-mail: m.a.waduud@doctors.org.uk; Choong, Wen Ling, E-mail: wenlingchoong@nhs.net; Ritchie, Moira, E-mail: moirasim9@gmail.com

PurposeEndovascular aneurysm repair (EVAR) is the dominant treatment strategy for abdominal aortic aneurysms. However, as a result of uncertainty regarding long-term durability, an ongoing imaging surveillance program is required. The aim of the study was to assess EVAR surveillance in Scotland and its effect on all-cause and aneurysm-related mortality.MethodsA retrospective analysis of all EVAR procedures carried out in the four main Scottish vascular units. The primary outcome measure was the implementation of post-EVAR imaging surveillance across Scotland. Patients were identified locally and then categorized as having complete, incomplete, or no surveillance. Secondary outcome measures were all-cause mortality and aneurysm-related mortality.more » Cause of death was obtained from death certificates.ResultsData were available for 569 patients from the years 2001 to 2012. All centers had data for a minimum of 5 contiguous years. Surveillance ranged from 1.66 to 4.55 years (median 3.03 years). Overall, 53 % had complete imaging surveillance, 43 % incomplete, and 4 % none. For the whole cohort, all-cause 5-year mortality was 33.5 % (95 % confidence interval 28.0–38.6) and aneurysm-related mortality was 4.5 % (.8–7.3). All-cause mortality in patients with complete, incomplete, and no imaging was 49.9 % (39.2–58.6), 19.1 % (12.6–25.2), and 47.2 % (17.7–66.2), respectively. Aneurysm-related mortality was 3.7 % (1.8–7.4), 4.4 % (2.2–8.9), and 9.5 % (2.5–33.0), respectively. All-cause mortality was significantly higher in patients with complete compared to incomplete imaging surveillance (p < 0.001). No significant differences were observed in aneurysm-related mortality (p = 0.2).ConclusionOnly half of EVAR patients underwent complete long-term imaging surveillance. However, incomplete imaging could not be linked to any increase in mortality. Further work is required to establish the role and deliverability of EVAR imaging surveillance.« less

Three-dimensional volume-rendering technique in the angiographic follow-up of intracranial aneurysms embolized with coils.

PubMed

Zhou, Bing; Li, Ming-Hua; Wang, Wu; Xu, Hao-Wen; Cheng, Yong-De; Wang, Jue

2010-03-01

The authors conducted a study to evaluate the advantages of a 3D volume-rendering technique (VRT) in follow-up digital subtraction (DS) angiography of coil-embolized intracranial aneurysms. One hundred nine patients with 121 intracranial aneurysms underwent endovascular coil embolization and at least 1 follow-up DS angiography session at the authors' institution. Two neuroradiologists independently evaluated the conventional 2D DS angiograms, rotational angiograms, and 3D VRT images obtained at the interventional procedures and DS angiography follow-up. If multiple follow-up sessions were performed, the final follow-up was mainly considered. The authors compared the 3 techniques for their ability to detect aneurysm remnants (including aneurysm neck and sac remnants) and parent artery stenosis based on the angiographic follow-up. The Kruskal-Wallis test was used for group comparisons, and the kappa test was used to measure interobserver agreement. Statistical analyses were performed using commercially available software. There was a high statistical significance among 2D DS angiography, rotational angiography, and 3D VRT results (X(2) = 9.9613, p = 0.0069) when detecting an aneurysm remnant. Further comparisons disclosed a statistical significance between 3D VRT and rotational angiography (X(2) = 4.9754, p = 0.0257); a high statistical significance between 3D VRT and 2D DS angiography (X(2) = 8.9169, p = 0.0028); and no significant difference between rotational angiography and 2D DS angiography (X(2) = 0.5648, p = 0.4523). There was no statistical significance among the 3 techniques when detecting parent artery stenosis (X(2) = 2.5164, p = 0.2842). One case, in which parent artery stenosis was diagnosed by 2D DS angiography and rotational angiography, was excluded by 3D VRT following observations of multiple views. The kappa test showed good agreement between the 2 observers. The 3D VRT is more sensitive in detecting aneurysm remnants than 2D DS angiography and rotational angiography and is helpful for identifying parent artery stenosis. The authors recommend this technique for the angiographic follow-up of patients with coil-embolized aneurysms.

Comparison of 3D TOF-MRA and 3D CE-MRA at 3T for imaging of intracranial aneurysms.

PubMed

Cirillo, Mario; Scomazzoni, Francesco; Cirillo, Luigi; Cadioli, Marcello; Simionato, Franco; Iadanza, Antonella; Kirchin, Miles; Righi, Claudio; Anzalone, Nicoletta

2013-12-01

To compare 3T elliptical-centric CE MRA with 3T TOF MRA for the detection and characterization of unruptured intracranial aneurysms (UIAs), by using digital subtracted angiography (DSA) as reference. Twenty-nine patients (12 male, 17 female; mean age: 62 years) with 41 aneurysms (34 saccular, 7 fusiform; mean diameter: 8.85 mm [range 2.0-26.4mm]) were evaluated with MRA at 3T each underwent 3D TOF-MRA examination without contrast and then a 3D contrast-enhanced (CE-MRA) examination with 0.1mmol/kg bodyweight gadobenate dimeglumine and k-space elliptic mapping (Contrast ENhanced Timing Robust Angiography [CENTRA]). Both TOF and CE-MRA images were used to evaluate morphologic features that impact the risk of rupture and the selection of a treatment. Almost half (20/41) of UIAs were located in the internal carotid artery, 7 in the anterior communicating artery, 9 in the middle cerebral artery and 4 in the vertebro-basilar arterial system. All patients also underwent DSA before or after the MR examination. The CE-MRA results were in all cases consistent with the DSA dataset. No differences were noted between 3D TOF-MRA and CE-MRA concerning the detection and location of the 41 aneurysms or visualization of the parental artery. Differences were apparent concerning the visualization of morphologic features, especially for large aneurysms (>13 mm). An irregular sac shape was demonstrated for 21 aneurysms on CE-MRA but only 13/21 aneurysms on 3D TOF-MRA. Likewise, CE-MRA permitted visualization of an aneurismal neck and calculation of the sac/neck ratio for all 34 aneurysms with a neck demonstrated at DSA. Conversely, a neck was visible for only 24/34 aneurysms at 3D TOF-MRA. 3D CE-MRA detected 15 aneurysms with branches originating from the sac and/or neck, whereas branches were recognized in only 12/15 aneurysms at 3D TOF-MRA. For evaluation of intracranial aneurysms at 3T, 3D CE-MRA is superior to 3D TOF-MRA for assessment of sac shape, detection of aneurysmal neck, and visualization of branches originating from the sac or neck itself, if the size of the aneurysm is greater than 13 mm. 3T 3D CE-MRA is as accurate and effective as DSA for the evaluation of UIAs. Copyright © 2013. Published by Elsevier Ireland Ltd.

Median Supraorbital Keyhole Approach for Clipping Ruptured Distal Anterior Cerebral Artery Aneurysm: Technical Report with Review of Literature.

PubMed

Dhandapani, Sivashanmugam; Sahoo, Sushant Kumar

2018-04-01

The minimally invasive approach to distal anterior cerebral artery (DACA) aneurysms has not gained much acceptance due to difficulties associated with the conventional frontal paramedian approach. The more proximal basal interhemispheric approach, however, necessitates extensive dissection of soft tissues. We describe a novel minimally invasive median supraorbital keyhole craniotomy with a basal interhemispheric approach for clipping a ruptured DACA aneurysm. A 62-year-old patient presented with subarachnoid hemorrhage. Computed tomography angiography revealed a DACA aneurysm. The surgical technique involved a keyhole craniotomy made via an eyebrow incision extending between the supraorbital notches, and flush with the anterior cranial fossa. The dura was opened at the anterior part, the falx was cut, an interhemispheric dissection was carried out, adequate proximal control was obtained, and the aneurysm neck was dissected and clipped. A relevant review of the literature was carried out. The patient recovered well, with no residual aneurysm or forehead numbness, with good cosmesis. Compared with the previously described "keyhole unilateral interhemispheric" approaches, our technique has less likelihood of encountering bridging veins; easier cisternal cerebrospinal fluid release, making it feasible even in swollen brain; better proximal vascular control; and trajectory toward the neck rather than dome. The median supraorbital keyhole approach is a minimally invasive technique sufficient for clipping most DACA aneurysms, with easier access, better proximal control, and good cosmesis. Copyright © 2018 Elsevier Inc. All rights reserved.

Dual-Channel Endoscopic Indocyanine Green Fluorescence Angiography for Clipping of Cerebral Aneurysms.

PubMed

Cho, Won-Sang; Kim, Jeong Eun; Kang, Hyun-Seung; Ha, Eun Jin; Jung, Minwoong; Lee, Choonghee; Shin, Il Hyung; Kang, Uk

2017-04-01

Neuroendoscopy is useful for assessing status of perforators, parent arteries, and aneurysms beyond the straight line of microscopic view during aneurysm clipping. We aimed to evaluate the clinical usefulness of our endoscopic indocyanine green angiography (ICGA) system, which can simultaneously display visible light and indocyanine green fluorescent images. Surgical clipping of 16 unruptured aneurysms in 10 patients was performed via the keyhole approach. Using our endoscopic ICGA and commercial microscopic ICGA systems, we prospectively compared 10 targeted cerebral aneurysms at the posterior communicating (n = 4) and anterior choroidal (n = 6) arteries. Microscopic ICGA and endoscopic ICGA were feasible during surgery. Microscopic ICGA displayed 50% of branch orifices, 100% of branch trunks, and 20% of exact clip positions, whereas endoscopic ICGA showed 100% of these. Based on endoscopic ICGA findings such as incomplete clipping and compromise of parent arteries or branches, clips were repositioned in 2 cases, and additional clips were applied in 2 cases. Complete occlusion and residual neck states were achieved in 6 and 4 aneurysms after surgery. There were no neurologic deficits within 3 months after surgery except for frontalis palsy and anosmia in each patient. The endoscopic ICGA system with dual imaging of visible light and indocyanine green fluorescence was very useful for assessing geometry of aneurysms and surrounding vessels before clipping and for evaluating completeness of clip position after clipping. Copyright © 2017 Elsevier Inc. All rights reserved.

GREAT-a randomized controlled trial comparing HydroSoft/HydroFrame and bare platinum coils for endovascular aneurysm treatment: procedural safety and core-lab-assessedangiographic results.

PubMed

Taschner, Christian A; Chapot, René; Costalat, Vincent; Machi, Paolo; Courthéoux, Patrick; Barreau, Xavier; Berge, Jérôme; Pierot, Laurent; Kadziolka, Kryzsztof; Jean, Betty; Blanc, Raphaël; Biondi, Alessandra; Brunel, Hervé; Gallas, Sophie; Berlis, Ansgar; Herbreteau, Denis; Berkefeld, Joachim; Urbach, Horst; El Shikh, Samer; Fiehler, Jens; Desal, Hubert; Graf, Erika; Bonafé, Alain

2016-08-01

Hybrid hydrogel-platinum coils (HydroCoil) have proven effective for endovascular aneurysm treatment. To overcome technical limitations (coil stiffness, time restriction for placement), a second generation of softer hydrogel coils has been brought to clinical practice (HydroSoft, HydroFrame). We report on procedural safety and core-lab-assessed angiographic results from an open-label multicenter randomized controlled trial. Web-based randomization occurred in 15 medical centers in France and seven in Germany between coil embolization with second-generation hydrogel coils and treatment with any bare platinum coil. Assist devices could be used as clinically required. Primary endpoint is a composite outcome including major aneurysm recurrence and poor clinical outcome at 18 months follow-up. Five hundred thirteen patients were randomized (hydrogel n = 256, bare platinum n = 257). Twenty patients were excluded for missing informed consent and nine patients for treatment related criteria. Four hundred eighty-four patients were analyzed as randomized (hydrogel n = 243, bare platinum n = 241). Two hundred eight had ruptured aneurysms (43 %). Prespecified procedural complications occurred in 58 subjects (hydrogel n = 28, bare platinum n = 30, p = 0.77). The 14-day mortality rate was 2.1 % in both arms of the study. The median calculated packing densities for aneurysms assigned to hydrogel and bare platinum were 39 and 31 % respectively (p < 0.001). No statistically significant differences were found between arms in the post procedural angiographic occlusion rate (p = 0.8). Second-generation hydrogel coils can be used in a wide spectrum of aneurysms with a risk profile equivalent to bare platinum. Packing density was significantly higher in aneurysms treated with hydrogel coils. http://www.germanctr.de , DRKS00003132.

Comparison of endovascular repair with branched stent graft and open repair for aortic arch aneurysm.

PubMed

Kawatou, Masahide; Minakata, Kenji; Sakamoto, Kazuhisa; Nakatsu, Taro; Tazaki, Junichi; Higami, Hirooki; Uehara, Kyokun; Yamazaki, Kazuhiro; Inoue, Kanji; Kimura, Takeshi; Sakata, Ryuzo

2017-08-01

Although conventional open repair is our preference for patients with aortic arch aneurysms, we have often chosen thoracic endovascular aneurysm repair (TEVAR) with a handmade branched stent graft (bTEVAR) in high-risk patients. The aim of this study was to compare the midterm clinical outcomes of our bTEVAR technique to those of the open repair. Between January 2007 and December 2014, we treated 129 patients with aortic arch aneurysm by means of either conventional open repair (OPEN, n = 61) or bTEVAR (n = 68) at our institution. The mean ages were 70.5 ± 12.7 years in the OPEN group and 72.7 ± 12.5 years in the bTEVAR group (P = 0.32). The aetiologies included true aneurysm in 101 patients (78.3%) and chronic dissection in 26 (20.1%). There were 2 (3.3%) in-hospital deaths in the OPEN group and 3 (4.4%) in the bTEVAR group. The mean follow-up duration was 3.0 ± 2.1 years (2.4 ± 1.9 years in the OPEN group and 3.6 ± 2.3 years in the bTEVAR group). There was no difference in 5-year aneurysm-related mortality between groups (10.7% in OPEN vs 12.8% in bTEVAR, P = 0.50). In terms of late additional procedures, however, none were required in the OPEN group, whereas 10 (15.4%) additional endovascular repairs and 4 (6.2%) open repairs were required in the bTEVAR group. Our bTEVAR could be performed with low early mortality, and it yielded similar midterm aneurysm-related mortality to that of conventional open repair. However, these patients undergoing this technique required more late additional procedures than those undergoing conventional open repair. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Fluid displacement from intraluminal thrombus of abdominal aortic aneurysm as a result of uniform compression.

PubMed

van Noort, Kim; Schuurmann, Richte Cl; Wermelink, Bryan; Slump, Cornelis H; Kuijpers, Karel C; de Vries, Jean-Paul Pm

2017-10-01

Objectives The results after aneurysm repair with an endovascular aneurysm sealing (EVAS) system are dependent on the stability of the aneurysm sac and particularly the intraluminal abdominal aortic thrombus (ILT). The postprocedural ILT volume is decreased compared with preprocedural ILT volume in aortic aneurysm patients treated with EVAS. We hypothesize that ILT is not stable in all patients and pressurization of the ILT may result in displacement of fluids from the ILT, no differently than serum is displaced from whole blood when it settles. To date, the mechanism and quantification of fluid displacement from ILT are unknown. Methods The study included 21 patients who underwent elective open abdominal aortic aneurysm repair. The ILT was harvested as a routine procedure during the operation. After excision of a histologic sample of the ILT specimen in four patients, ILT volume was measured and the ILT was compressed in a dedicated compression setup designed to apply uniform compression of 200 mmHg for 5 min. After compression, the volumes of the remaining thrombus and the displaced fluid were measured. Results The median (interquartile-range) of ILT volume before compression was 60 (66) mL, and a median of 5.7 (8.4) mL of fluid was displaced from the ILT after compression, resulting in a median thrombus volume decrease of 11% (10%). Fluid components can be up to 31% of the entire ILT volume. Histologic examination of four ILT specimens showed a reduction of the medial layer of the ILT after compression, which was the result of compression of fluid-containing canaliculi. Conclusions Applying pressure of 200 mmHg to abdominal aortic aneurysm ILT resulted in the displacement of fluid, with a large variation among patients. Fluid displacement may result in decrease of ILT volume during and after EVAS, which might have implications on pre-EVAS volume planning and on stability of the endobags during follow-up which may lead to migration, endoleak or both.

Coronary artery aneurysm combined with other multiple aneurysms at multiple locations: A case report and systematic review.

PubMed

Jiang, Li-Cheng; Cao, Jia-Yu; Chen, Mao

2017-12-01

Coronary artery aneurysm (CAA) with concomitant aneurysms at multiple sites is quite unusual and rare. The characteristics and the etiology of this phenomenon are unknown. Herein, we present a case with right coronary aneurysm with concomitant abdominal aorta as well as right renal artery aneurysm. A systematic review of the literatures regarding CAA with other coexisting aneurysms at multiple locations was also conducted on Medline and Embase databases. A total of 76 patients (male gender: 58; age: 37.4 ± 26.5) including the present case were included in the final study. The most common etiology of CAA with multiple aneurysms was Kawasaki (43.3%) and atherosclerotic disease (16.4%). CAA was the most frequently found at the right coronary artery (62.7%), following, left anterior descending (51%), left main (43.1%), and left circumflex (35.3%). The most common concomitant aneurysms were abdominal aorta (52.6%) and iliac artery (50%). In addition, 60.5% of the patients had an involved bilateral peripheral artery. CAA with coexisting systemic aneurysms in multiple sites is quite rare. And it usually involves multiple aneurysms at the coronary and bilateral peripheral arteries simultaneously. Currently, there are no general consensus regarding the clinical characteristics, diagnostic method, and treatment of these cases. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

Cellular responses of bioabsorbable polymeric material and Guglielmi detachable coil in experimental aneurysms.

PubMed

Murayama, Yuichi; Viñuela, Fernando; Tateshima, Satoshi; Gonzalez, Nestor R; Song, Joon K; Mahdavieh, Haleh; Iruela-Arispe, Luisa

2002-04-01

Acceleration of healing mechanisms is a promising approach to improve current limitations of endovascular aneurysm therapy with the use of platinum coils. We evaluated a new endovascular therapeutic, bioabsorbable polymeric material (BPM), which may promote cellular reaction in the aneurysms. Four different concentrations of lactide/glycolic acid copolymer [poly(D-L-lactic-co-glycolic acid)] (PLGA), 85/15, 75/25, 65/35, and 50/50, were used as BPMs. Sixteen experimental aneurysms were created in 8 swine. Eight-millimeter-long spiral-shaped BPMs were surgically implanted in the aneurysms without tight packing (n=3 for each BPM). Guglielmi detachable coils (GDCs) were used as control (n=4). The animals were killed 14 days after embolization, and angiographic, histological, and immunohistochemical analyses were performed. Despite loose packing of aneurysms with BPMs, faster BPMs such as 50/50 or 65/35 PLGA demonstrated more mature collagen formation and fibrosis in the sac and neck of the aneurysm. One aneurysm treated with 65/35 PLGA, 1 treated with 75/25 PLGA, and all 3 treated with 85/15 PLGA showed a neck remnant on angiography. There was a linear relationship between collagen levels and polymer degradation properties (r=-0.9513). This preliminary animal study indicates that acceleration of aneurysm healing with the use of BPM is feasible. This concept can be applied to decrease and perhaps prevent aneurysmal recanalization after endovascular treatment of cerebral aneurysms.

Preclinical Evaluation of RYM1, a Matrix Metalloproteinase-Targeted Tracer for Imaging Aneurysm.

PubMed

Toczek, Jakub; Ye, Yunpeng; Gona, Kiran; Kim, Hye-Yeong; Han, Jinah; Razavian, Mahmoud; Golestani, Reza; Zhang, Jiasheng; Wu, Terence L; Jung, Jae-Joon; Sadeghi, Mehran M

2017-08-01

Matrix metalloproteinases (MMPs) play a key role in abdominal aortic aneurysm (AAA) development. Accordingly, MMP-targeted imaging provides important information regarding vessel wall biology in the course of aneurysm development. Given the small size of the vessel wall and its proximity with blood, molecular imaging of aneurysm optimally requires highly sensitive tracers with rapid blood clearance. To this end, we developed a novel hydrosoluble zwitterionic MMP inhibitor, RYM, on the basis of which a pan-MMP tracer, RYM1, was designed. Here, we describe the development and preclinical evaluation of RYM1 in comparison with RP805, a commonly used pan-MMP tracer in murine models of aneurysm. Methods: The macrocyclic hydroxamate-based pan-MMP inhibitor coupled with 6-hydrazinonicotinamide, RYM1, was synthesized and labeled with 99m Tc. Radiochemical stability of 99m Tc-RYM1 was evaluated by radio-high-performance liquid chromatography analysis. Tracer blood kinetics and biodistribution were compared with 99m Tc-RP805 in C57BL/6J mice ( n = 10). 99m Tc-RYM1 binding to aneurysm and specificity were evaluated by quantitative autoradiography in apolipoprotein E-deficient (apoE -/- ) mice with CaCl 2 -induced carotid aneurysm ( n = 11). Angiotensin II-infused apoE -/- ( n = 16) mice were used for small-animal SPECT/CT imaging. Aortic tissue MMP activity and macrophage marker CD68 expression were assessed by zymography and reverse-transcription polymerase chain reaction. Results: RYM1 showed nanomolar range inhibition constants for several MMPs. 99m Tc-RYM1 was radiochemically stable in mouse blood for 5 h and demonstrated rapid renal clearance and lower blood levels in vivo compared with 99m Tc-RP805. 99m Tc-RYM1 binding to aneurysm and its specificity were shown by autoradiography in carotid aneurysm. Angiotensin II infusion in apoE -/- mice for 4 wk resulted in AAA formation in 36% (4/11) of surviving animals. In vivo 99m Tc-RYM1 small-animal SPECT/CT images showed higher uptake of the tracer in AAA than nondilated aortae. Finally, aortic uptake of 99m Tc-RYM1 in vivo correlated with aortic MMP activity and CD68 expression. Conclusion: The newly developed pan-MMP inhibitor-based tracer 99m Tc-RYM1 displays favorable pharmacokinetics for early vascular imaging and enables specific detection of inflammation and MMP activity in aneurysm. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

The Role of Oxidative Stress in Cerebral Aneurysm Formation and Rupture

PubMed Central

Starke, Robert M.; Chalouhi, Nohra; Ali, Muhammad S.; Jabbour, Pascal M.; Tjoumakaris, Stavropoula I.; Gonzalez, L. Fernando; Rosenwasser, Robert H.; Koch, Walter J.; Dumont, Aaron S.

2013-01-01

Oxidative stress is known to contribute to the progression of cerebrovascular disease. Additionally, oxidative stress may be increased by, but also augment inflammation, a key contributor to cerebral aneurysm development and rupture. Oxidative stress can induce important processes leading to cerebral aneurysm formation including direct endothelial injury as well as smooth muscle cell phenotypic switching to an inflammatory phenotype and ultimately apoptosis. Oxidative stress leads to recruitment and invasion of inflammatory cells through upregulation of chemotactic cytokines and adhesion molecules. Matrix metalloproteinases can be activated by free radicals leading to vessel wall remodeling and breakdown. Free radicals mediate lipid peroxidation leading to atherosclerosis and contribute to hemodynamic stress and hypertensive pathology, all integral elements of cerebral aneurysm development. Preliminary studies suggest that therapies targeted at oxidative stress may provide a future beneficial treatment for cerebral aneurysms, but further studies are indicated to define the role of free radicals in cerebral aneurysm formation and rupture. The goal of this review is to assess the role of oxidative stress in cerebral aneurysm pathogenesis. PMID:23713738

Revascularization of the anterior cerebral artery by Y-shaped superficial temporal artery interposition graft for the treatment of a de novo aneurysm arising at the site of A3-A3 bypass: technical case report.

PubMed

Endo, Hidenori; Sugiyama, Shin-Ichiro; Endo, Toshiki; Fujimura, Miki; Shimizu, Hiroaki; Tominaga, Teiji

2017-12-22

The most frequently used option to reconstruct the anterior cerebral artery (ACA) is an ACA-ACA side-to-side anastomosis. The long-term outcome and complications of this technique are unclear. The authors report a case of a de novo aneurysm arising at the site of A 3 -A 3 anastomosis. A 53-year-old woman underwent A 3 -A 3 side-to-side anastomosis for the treatment of a ruptured right A 2 dissecting aneurysm. At 44 months after surgery, a de novo aneurysm developed at the site of anastomosis. The aneurysm developed in the front wall of the anastomosis site, and projected to the anterosuperior direction. A computational fluid dynamics (CFD) study showed the localized region with high wall shear stress coincident with the pulsation in the front wall of the anastomosis site, where the aneurysm developed. A Y-shaped superficial temporal artery (STA) interposition graft was used successfully to reconstruct both ACAs, and then the aneurysm was trapped. To the authors' knowledge, this is the first case of a de novo aneurysm that developed at the site of an ACA-ACA side-to-side anastomosis. A CFD study showed that hemodynamic stress might be an underlying cause of the aneurysm formation. A Y-shaped STA interposition graft is a useful option to treat this aneurysm. Long-term follow-up is necessary to detect this rare complication after ACA-ACA anastomosis.

Stent-assisted coil embolization of intracranial aneurysms: a single center experience.

PubMed

Luo, Chao-Bao; Teng, Michael Mu-Huo; Chang, Feng-Chi; Lin, Chung-Jung; Guo, Wan-Yuo; Chang, Cheng-Yen

2012-07-01

Endovascular detachable coil embolization has become an important method in the management of intracranial aneurysms. However, coil embolization alone may fail to treat some wide-neck aneurysms. Herein, we report our experience with and outcome of stent-assisted coil embolization (SACE) of intracranial aneurysms. Over a 5-year period, a total of 59 patients diagnosed with 63 intracranial aneurysms underwent SACE. Of the total 63 aneurysms, 6 aneurysms were treated by SACE as a salvageable procedure because of coil instability after detachment. There were 17 men and 42 women enrolled in the study, with ages ranging from 24 to 86 years (mean: 60 years). We retrospectively assessed the clinical data, aneurysm characteristics, and angiographic and clinical outcomes of all patient cases. The mean aneurysm size was 9.4 mm, and the mean neck size was 5.5 mm. Clinical and angiographic follow-up exceeding 6 months were available in 51 and 40 patients, respectively. The mean clinical follow-up time was 28 months (range: 6-49 months). Successful stent deployment was found in 60 aneurysms (95%). Midterm total or subtotal angiographic aneurismal occlusion was obtained in 56 aneurysms (89%), with further thrombosis of the aneurismal sac occurring in 4 (10%). Stable coiling aneurysm was found in 24 (78%), aneurysm recurrence was observed in 5 (13%), and permanent procedural morbidity was observed in two patients (3.4%). During the follow-up period, there were no hemorrhagic events and no stent displacement. Despite a modest procedural complication rate, and some evidence of aneurismal recurrence, SACE was proved to be both effective and safe in managing wide-neck intracranial aneurysms. Our results also demonstrated the midterm durability and stability of aneurysm treated by SACE. Furthermore, SACE can be a salvageable procedure in cases with coil instability after detachment. Copyright © 2012. Published by Elsevier B.V.

Hemodynamic simulations in coronary aneurysms of children with Kawasaki disease

NASA Astrophysics Data System (ADS)

Sengupta, Dibyendu; Burns, Jane; Marsden, Alison

2009-11-01

Kawasaki disease (KD) is a serious pediatric illness affecting the cardiovascular system. One of the most serious complications of KD, occurring in about 25% of untreated cases, is the formation of large aneurysms in the coronary arteries, which put patients at risk for myocardial infarction. In this project we performed patient specific computational simulations of blood flow in aneurysmal left and right coronary arteries of a KD patient to gain an understanding about their hemodynamics. Models were constructed from CT data using custom software. Typical pulsatile flow waveforms were applied at the model inlets, while resistance and RCR lumped models were applied and compared at the outlets. Simulated pressure waveforms compared well with typical physiologic data. High wall shear stress values are found in the narrow region at the base of the aneurysm and low shear values occur in regions of recirculation. A Lagrangian approach has been adopted to perform particle tracking and compute particle residence time in the recirculation. Our long-term goal will be to develop links between hemodynamics and the risk for thrombus formation in order to assist in clinical decision-making.

Recovery of cognitive function after surgery for aneurysmal subarachnoid hemorrhage.

PubMed

Samra, Satwant K; Giordani, Bruno; Caveney, Angela F; Clarke, William R; Scott, Phillip A; Anderson, Steven; Thompson, Byron G; Todd, Michael M

2007-06-01

Abnormalities in neurocognitive function are common after surgery for aneurysmal subarachnoid hemorrhage, even among patients with good functional outcomes. The time course of neurocognitive recovery, along with the long-term effects of mild intraoperative hypothermia (33 degrees C) and aneurysm location, is unknown. We determined these in a subset of subarachnoid hemorrhage patients enrolled in the Intraoperative Hypothermia for Aneurysm Surgery Trial (IHAST). We performed a longitudinal, multicenter, prospective, blinded study of adult IHAST patients with a Glasgow Outcome Score=1 or 2 (independent function), 3 months postsurgery and a matched control group (n=45). Subjects were tested with a 5-test cognitive function battery and standard neurological evaluations at 3, 9 and 15 months postsurgery. The primary outcome measure was a composite score on cognitive test performance. There were 303 IHAST patients available for inclusion: 218 eligible, 185 enrolled (89 hypothermic, 96 normothermic). Significant cognitive improvement was noted from 3 to 9 (P<0.001) and 3 to 15 (P<0.001) months in both hypothermic and normothermic groups, even after adjusting for practice effects observed in the control group. No significant change was identified between 9 and 15 months. Neither mild hypothermia nor aneurysm location (anterior communicating artery versus others) had a significant effect on recovery over time or frequency of cognitive impairment. Compared with control group, the frequency of cognitive impairment (Z score <-1.96) in all patients at 3, 9 and 15 months was 36%, 26% and 23%, respectively. In this population, cognitive improvement continued beyond 3 months, with a plateau between 9 and 15 months. This was not affected by the use of intraoperative hypothermia or anatomical location of aneurysm.

A review of the surgical management of right-sided aortic arch aneurysms

PubMed Central

Barr, James G.; Sepehripour, Amir H.; Jarral, Omar A.; Tsipas, Pantelis; Kokotsakis, John; Kourliouros, Antonios; Athanasiou, Thanos

2016-01-01

Aneurysms and dissections of the right-sided aortic arch are rare and published data are limited to a few case reports and small series. The optimal treatment strategy of this entity and the challenges associated with their management are not yet fully investigated and conclusive. We performed a systematic review of the literature to identify all patients who underwent surgical or endovascular intervention for right aortic arch aneurysms or dissections. The search was limited to the articles published only in English. We focused on presentation and critically assessed different management strategies and outcomes. We identified 74 studies that reported 99 patients undergoing surgical or endovascular intervention for a right aortic arch aneurysm or dissection. The median age was 61 years. The commonest presenting symptoms were chest or back pain and dysphagia. Eighty-eight patients had an aberrant left subclavian artery with only 11 patients having the mirror image variant of a right aortic arch. The commonest pathology was aneurysm arising from a Kommerell's diverticulum occurring in over 50% of the patients. Twenty-eight patients had dissections, 19 of these were Type B and 9 were Type A. Eighty-one patients had elective operations while 18 had emergency procedures. Sixty-seven patients underwent surgical treatment, 20 patients had hybrid surgical and endovascular procedures and 12 had totally endovascular procedure. There were 5 deaths, 4 of which were in patients undergoing emergency surgery and none in the endovascular repair group. Aneurysms and dissections of a right-sided aortic arch are rare. Advances in endovascular treatment and hybrid surgical and endovascular management are making this rare pathology amenable to these approaches and may confer improved outcomes compared with conventional extensive repair techniques. PMID:27001673

Three-year experience with interventional neuroradiology for management of cerebral aneurysms at a single Australian centre.

PubMed

McLaughlin, Aden; Rice, Hal; de Viliers, Laetitia; Withers, Teresa; Pearson, David; Arnell, Moira; Walters, Kerin; Czuchwicki, Sarah; Bulmer, Andrew; Winearls, James

2018-02-01

Over the last decade interventional neuroradiology (NR) has become the mainstay of managing cerebral aneurysms. The aim of our study was to review our growing experiences with interventional NR and quantify morbidity and mortality associated with these procedures. The electronic medical records of all patients admitted to the Gold Coast (University) Hospital Intensive Care Unit following subarachnoid haemorrhage (SAH) or elective interventional NR management of cerebral aneurysms between January 2012 and December 2014 were retrieved. Primary outcomes of interest were death, thromboembolic and haemorrhagic events during hospital admission. One hundred and fifty-two patients underwent interventional NR procedures for cerebral aneurysms. This consisted of 92 (60.5%) elective cases and 60 (39.5%) emergency cases following SAH. The all-cause mortality rate and the rate of thromboembolic and haemorrhagic events for the entire cohort were 5.9%, 11.2% and 7.2% respectively. Intra-procedural complications occurred in 6.6% of the entire cohort. Median length of follow-up was 448 days, with 91.6% of the entire cohort followed up. At follow-up, 64.1% of patients had no neurological deficits, 29% had mild non-specific deficits and 6.9% had significant disability. Interventional NR represents the primary treatment modality for all patients presenting to our service with cerebral aneurysm. Our results are encouraging and are comparable to published data in the international literature. Reducing the burden of thromboembolism in patients undergoing endovascular treatment of their aneurysmal disease is our main research focus currently, and we aim to improve outcomes for this patient group. © 2017 The Royal Australian and New Zealand College of Radiologists.

Epidemiology, genetic, natural history and clinical presentation of giant cerebral aneurysms.

PubMed

Lonjon, M; Pennes, F; Sedat, J; Bataille, B

2015-12-01

Giant cerebral aneurysms represent 5% of intracranial aneurysms, and become symptomatic between 40 and 70 years with a female predominance. In the paediatric population, the giant aneurysm rate is higher than in the adult population. Classified as saccular, fusiform and serpentine, the natural history of giant cerebral aneurysms is characterized by thrombosis, growth and rupture. The pathogenesis of these giant aneurysms is influenced by a number of risk factors, including genetic variables. Genome-wide association studies have identified some chromosomes highlighting candidate genes. Although these giant aneurysms can occur at the same locations as their smaller counterparts, a predilection for the cavernous location has been observed. Giant aneurysms present with symptoms caused by a mass effect depending on their location or by rupture; ischemic manifestations rarely reveal the aneurysm. If the initial clinical descriptions have been back up by imagery, the clinical context with a pertinent analysis of the risk factors remain the cornerstone for the management decisions of these lesions. Five year cumulative rupture rates for patients with giant aneurysm were 40% for those located on the anterior part of circle of Willis and 50% for those on the posterior part. The poor outcome of untreated patients justifies the therapeutic risks. Copyright © 2015. Published by Elsevier Masson SAS.

Fluid-structure interaction modeling of aneurysmal arteries under steady-state and pulsatile blood flow: a stability analysis.

PubMed

Sharzehee, Mohammadali; Khalafvand, Seyed Saeid; Han, Hai-Chao

2018-02-01

Tortuous aneurysmal arteries are often associated with a higher risk of rupture but the mechanism remains unclear. The goal of this study was to analyze the buckling and post-buckling behaviors of aneurysmal arteries under pulsatile flow. To accomplish this goal, we analyzed the buckling behavior of model carotid and abdominal aorta with aneurysms by utilizing fluid-structure interaction (FSI) method with realistic waveforms boundary conditions. FSI simulations were done under steady-state and pulsatile flow for normal (1.5) and reduced (1.3) axial stretch ratios to investigate the influence of aneurysm, pulsatile lumen pressure and axial tension on stability. Our results indicated that aneurysmal artery buckled at the critical buckling pressure and its deflection nonlinearly increased with increasing lumen pressure. Buckling elevates the peak stress (up to 118%). The maximum aneurysm wall stress at pulsatile FSI flow was (29%) higher than under static pressure at the peak lumen pressure of 130 mmHg. Buckling results show an increase in lumen shear stress at the inner side of the maximum deflection. Vortex flow was dramatically enlarged with increasing lumen pressure and artery diameter. Aneurysmal arteries are more susceptible than normal arteries to mechanical instability which causes high stresses in the aneurysm wall that could lead to aneurysm rupture.

A novel strategy to translate the biomechanical rupture risk of abdominal aortic aneurysms to their equivalent diameter risk: method and retrospective validation.

PubMed

Gasser, T C; Nchimi, A; Swedenborg, J; Roy, J; Sakalihasan, N; Böckler, D; Hyhlik-Dürr, A

2014-03-01

To translate the individual abdominal aortic aneurysm (AAA) patient's biomechanical rupture risk profile to risk-equivalent diameters, and to retrospectively test their predictability in ruptured and non-ruptured aneurysms. Biomechanical parameters of ruptured and non-ruptured AAAs were retrospectively evaluated in a multicenter study. General patient data and high resolution computer tomography angiography (CTA) images from 203 non-ruptured and 40 ruptured aneurysmal infrarenal aortas. Three-dimensional AAA geometries were semi-automatically derived from CTA images. Finite element (FE) models were used to predict peak wall stress (PWS) and peak wall rupture index (PWRI) according to the individual anatomy, gender, blood pressure, intra-luminal thrombus (ILT) morphology, and relative aneurysm expansion. Average PWS diameter and PWRI diameter responses were evaluated, which allowed for the PWS equivalent and PWRI equivalent diameters for any individual aneurysm to be defined. PWS increased linearly and PWRI exponentially with respect to maximum AAA diameter. A size-adjusted analysis showed that PWS equivalent and PWRI equivalent diameters were increased by 7.5 mm (p = .013) and 14.0 mm (p < .001) in ruptured cases when compared to non-ruptured controls, respectively. In non-ruptured cases the PWRI equivalent diameters were increased by 13.2 mm (p < .001) in females when compared with males. Biomechanical parameters like PWS and PWRI allow for a highly individualized analysis by integrating factors that influence the risk of AAA rupture like geometry (degree of asymmetry, ILT morphology, etc.) and patient characteristics (gender, family history, blood pressure, etc.). PWRI and the reported annual risk of rupture increase similarly with the diameter. PWRI equivalent diameter expresses the PWRI through the diameter of the average AAA that has the same PWRI, i.e. is at the same biomechanical risk of rupture. Consequently, PWRI equivalent diameter facilitates a straightforward interpretation of biomechanical analysis and connects to diameter-based guidelines for AAA repair indication. PWRI equivalent diameter reflects an additional diagnostic parameter that may provide more accurate clinical data for AAA repair indication. Copyright © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Antihyperglycemic Agents Are Inversely Associated With Intracranial Aneurysm Rupture.

PubMed

Can, Anil; Castro, Victor M; Yu, Sheng; Dligach, Dmitriy; Finan, Sean; Gainer, Vivian S; Shadick, Nancy A; Savova, Guergana; Murphy, Shawn; Cai, Tianxi; Weiss, Scott T; Du, Rose

2018-01-01

Previous studies have suggested a protective effect of diabetes mellitus on aneurysmal subarachnoid hemorrhage risk. However, reports are inconsistent, and objective measures of hyperglycemia in these studies are lacking. Our aim was to investigate the association between aneurysmal subarachnoid hemorrhage and antihyperglycemic agent use and glycated hemoglobin levels. The medical records of 4701 patients with 6411 intracranial aneurysms, including 1201 prospective patients, diagnosed at the Massachusetts General Hospital and Brigham and Women's Hospital between 1990 and 2016 were reviewed and analyzed. Patients were separated into ruptured and nonruptured groups. Univariate and multivariate logistic regression analyses were performed to determine the association between aneurysmal subarachnoid hemorrhage and antihyperglycemic agents and glycated hemoglobin levels. Propensity score weighting was used to account for selection bias. In both unweighted and weighted multivariate analysis, antihyperglycemic agent use was inversely and significantly associated with ruptured aneurysms (unweighted odds ratio, 0.58; 95% confidence interval, 0.39-0.87; weighted odds ratio, 0.57; 95% confidence interval, 0.34-0.96). In contrast, glycated hemoglobin levels were not significantly associated with rupture status. Antihyperglycemic agent use rather than hyperglycemia is associated with decreased risk of aneurysmal subarachnoid hemorrhage, suggesting a possible protective effect of glucose-lowering agents in the pathogenesis of aneurysm rupture. © 2017 American Heart Association, Inc.

The significant impact of framing coils on long-term outcomes in endovascular coiling for intracranial aneurysms: how to select an appropriate framing coil.

PubMed

Ishida, Wataru; Sato, Masayuki; Amano, Tatsuo; Matsumaru, Yuji

2016-09-01

OBJECTIVE The importance of a framing coil (FC)-the first coil inserted into an aneurysm during endovascular coiling, also called a lead coil or a first coil-is recognized, but its impact on long-term outcomes, including recanalization and retreatment, is not well established. The purposes of this study were to test the hypothesis that the FC is a significant factor for aneurysmal recurrence and to provide some insights on appropriate FC selection. METHODS The authors retrospectively reviewed endovascular coiling for 280 unruptured intracranial aneurysms and gathered data on age, sex, aneurysm location, aneurysm morphology, maximal size, neck width, adjunctive techniques, recanalization, retreatment, follow-up periods, total volume packing density (VPD), volume packing density of the FC, and framing coil percentage (FCP; the percentage of FC volume in total coil volume) to clarify the associated factors for aneurysmal recurrence. RESULTS Of 236 aneurysms included in this study, 33 (14.0%) had recanalization, and 18 (7.6%) needed retreatment during a mean follow-up period of 37.7 ± 16.1 months. In multivariate analysis, aneurysm size (odds ratio [OR] = 1.29, p < 0.001), FCP < 32% (OR 3.54, p = 0.009), and VPD < 25% (OR 2.96, p = 0.015) were significantly associated with recanalization, while aneurysm size (OR 1.25, p < 0.001) and FCP < 32% (OR 6.91, p = 0.017) were significant predictors of retreatment. VPD as a continuous value or VPD with any cutoff value could not predict retreatment with statistical significance in multivariate analysis. CONCLUSIONS FCP, which is equal to the FC volume as a percentage of the total coil volume and is unaffected by the morphology of the aneurysm or the measurement error in aneurysm length, width, or height, is a novel predictor of recanalization and retreatment and is more significantly predictive of retreatment than VPD. To select FCs large enough to meet the condition of FCP ≥ 32% is a potential relevant factor for better long-term outcomes. These findings support our hypothesis that the FC is a significant factor for aneurysmal recurrence.

The inflammatory response to ruptured abdominal aortic aneurysm is altered by endovascular repair.

PubMed

Makar, R R; Badger, S A; O'Donnell, M E; Soong, C V; Lau, L L; Young, I S; Hannon, R J; Lee, B

2013-01-01

Introduction. Ruptured abdominal aortic aneurysm (rAAA) causes a significant inflammatory response. The study aims to investigate this response following endovascular and open repair of ruptured AAA. Patients and Methods. Consecutive rAAA patients had either endovascular aneurysm repair (EVAR) or open repair (OR). Blood samples were taken for cytokines, lipid hydroperoxides (LOOH), antioxidants, and neutrophil elastase/ α 1-anti-trypsin complexes (NE/AAT) before surgery, 6 hours after clamp release and 1, 3, 5 days postoperatively. Results. 30 patients were included in the study, with 14 undergoing eEVAR and 16 eOR, with comparable baseline comorbidities, age, and parameters. IL-6 peaked higher in eOR patients (P = 0.04), while p75TNFr was similar between groups except at day 5 (P = 0.04). The NE/AAT concentrations were higher in eOR patients (P = 0.01), particularly in the first postoperative day, and correlated with blood (r = 0.398, P = 0.029) and platelet (r = 0.424, P = 0.020) volume transfused. C-reactive protein rose and lipid hydroperoxide fell in both groups without significant intergroup difference. Vitamins C and E, lycopene, and β -carotene levels were similar between groups. Conclusion. EVAR is associated with lower systemic inflammatory response compared to OR. Its increased future use may thereby improve outcomes for patients.

The Inflammatory Response to Ruptured Abdominal Aortic Aneurysm Is Altered by Endovascular Repair

PubMed Central

Makar, R. R.; Badger, S. A.; O'Donnell, M. E.; Soong, C. V.; Lau, L. L.; Young, I. S.; Hannon, R. J.; Lee, B.

2013-01-01

Introduction. Ruptured abdominal aortic aneurysm (rAAA) causes a significant inflammatory response. The study aims to investigate this response following endovascular and open repair of ruptured AAA. Patients and Methods. Consecutive rAAA patients had either endovascular aneurysm repair (EVAR) or open repair (OR). Blood samples were taken for cytokines, lipid hydroperoxides (LOOH), antioxidants, and neutrophil elastase/α1-anti-trypsin complexes (NE/AAT) before surgery, 6 hours after clamp release and 1, 3, 5 days postoperatively. Results. 30 patients were included in the study, with 14 undergoing eEVAR and 16 eOR, with comparable baseline comorbidities, age, and parameters. IL-6 peaked higher in eOR patients (P = 0.04), while p75TNFr was similar between groups except at day 5 (P = 0.04). The NE/AAT concentrations were higher in eOR patients (P = 0.01), particularly in the first postoperative day, and correlated with blood (r = 0.398, P = 0.029) and platelet (r = 0.424, P = 0.020) volume transfused. C-reactive protein rose and lipid hydroperoxide fell in both groups without significant intergroup difference. Vitamins C and E, lycopene, and β-carotene levels were similar between groups. Conclusion. EVAR is associated with lower systemic inflammatory response compared to OR. Its increased future use may thereby improve outcomes for patients. PMID:24363936

The Biochemical Basis of Hydroxymethylglutaryl-CoA Reductase Inhibitors as Neuroprotective Agents in Aneurysmal Subarachnoid Hemorrhage

PubMed Central

Wong, George Kwok Chu; Poon, Wai Sang

2010-01-01

Aneurysmal subarachnoid hemorrhage (SAH) has the highest morbidity and mortality rates of all types of stroke. Many aneurysmal SAH patients continue to suffer from significant neurological morbidity and mortality directly related to delayed cerebral ischemia. Pilot clinical studies of the use of Hydroxymethylglutaryl-CoA Reductase Inhibitors (statins) in aneurysmal SAH patients have reported a reduction in delayed cerebral ischemia and better clinical outcomes. We review the biochemical effects of statins on endothelium vascular function, glutamate-mediated neurotoxicity, inflammatory changes, and oxidative injuries, with reference to their possible neuroprotective effects in aneurysmal SAH.

High-dose aspirin for Kawasaki disease: outdated myth or effective aid?

PubMed

Amarilyo, Gil; Koren, Yael; Brik Simon, Dafna; Bar-Meir, Maskit; Bahat, Hilla; Helou, Mona Hanna; Mendelson, Amir; Hezkelo, Nofar; Chodick, Gabriel; Berkun, Yackov; Eisenstein, Eli; Butbul Aviel, Yonatan; Barkai, Galia; Bolkier, Yoav; Padeh, Shai; Brik, Riva; Hashkes, Phillip J; Harel, Liora; Uziel, Yosef

2017-01-01

To compare the efficacy and safety of intravenous immunoglobulin (IVIG) plus high-dose aspirin (HDA) vs. IVIG plus low-dose aspirin (LDA) for the treatment of Kawasaki disease, with an emphasis on coronary artery outcomes. This study was a retrospective, medical record review of paediatric patients with Kawasaki disease comparing 6 centres that routinely used HAD for initial treatment and 2 that used LDA in 2004-2013. Treatment response and adverse events were compared. The primary outcome measure was the occurrence of coronary aneurysm at the subacute or convalescent stage. The cohort included 358 patients, of whom 315 were initially treated with adjunctive HDA and 43 with LDA. There were no demographic differences between the groups. Coronary aneurysms occurred in 10% (20/196) of the HDA group and 4% (1/24) of the LDA group (p=0.34). Equivalence tests indicate it is unlikely that the risk of coronary aneurysm in LDA exceeds HDA by more than 3.5%. There were no significant between-group differences in the need for glucocorticoid pulse therapy or disease recurrence. Coronary ectasia rate and hospitalisation time were significantly greater in the HDA group. Adverse events were similar in the two groups. We found no significant clinical benefit in using IVIG+HDA in Kawasaki disease compared to IVIG+LDA. The use of adjunctive HDA in this setting should be reconsidered.

Third nerve palsy caused by compression of the posterior communicating artery aneurysm does not depend on the size of the aneurysm, but on the distance between the ICA and the anterior-posterior clinoid process.

PubMed

Anan, Mitsuhiro; Nagai, Yasuyuki; Fudaba, Hirotaka; Kubo, Takeshi; Ishii, Keisuke; Murata, Kumi; Hisamitsu, Yoshinori; Kawano, Yoshihisa; Hori, Yuzo; Nagatomi, Hirofumi; Abe, Tatsuya; Fujiki, Minoru

2014-08-01

Third nerve palsy (TNP) caused by a posterior communicating artery (PCoA) aneurysm is a well-known symptom of the condition, but the characteristics of unruptured PCoA aneurysm-associated third nerve palsy have not been fully evaluated. The aim of this study was to analyze the anatomical features of PCoA aneurysms that caused TNP from the viewpoint of the relationship between the ICA and the skull base. Forty-eight unruptured PCoA aneurysms were treated surgically between January 2008 and September 2013. The characteristics of the aneurysms were evaluated. Thirteen of the 48 patients (27%) had a history of TNP. The distance between the ICA and the anterior-posterior clinoid process (ICA-APC distance) was significantly shorter in the TNP group (p<0.01), but the maximum size of the aneurysms was not (p=0.534). Relatively small unruptured PCoA aneurysms can cause third nerve palsy if the ICA runs close to the skull base. Copyright © 2014 Elsevier B.V. All rights reserved.

Morphological Variables Associated With Ruptured Middle Cerebral Artery Aneurysms.

PubMed

Zhang, Jian; Can, Anil; Mukundan, Srinivasan; Steigner, Michael; Castro, Victor M; Dligach, Dmitriy; Finan, Sean; Yu, Sheng; Gainer, Vivian; Shadick, Nancy A; Savova, Guergana; Murphy, Shawn; Cai, Tianxi; Wang, Zhong; Weiss, Scott T; Du, Rose

2018-05-30

Geometric factors of intracranial aneurysms and surrounding vasculature could affect the risk of aneurysm rupture. However, large-scale assessments of morphological parameters correlated with intracranial aneurysm rupture in a location-specific manner are scarce. To investigate the morphological characteristics associated with ruptured middle cerebral artery (MCA) aneurysms. Five hundred sixty-one patients with 638 MCA aneurysms diagnosed between 1990 and 2016 who had available computed tomography angiography (CTA) were included in this study. CTAs were evaluated using the Vitrea Advanced Visualization software for 3-dimensional (3D) reconstruction. Morphological parameters examined in each model included aneurysm projection, wall irregularity, presence of a daughter dome, presence of hypoplastic or aplastic A1 arteries and hypoplastic or fetal posterior communicating arteries (PCoA), aneurysm height and width, neck diameter, bottleneck factor, aspect and size ratio, height/width ratio, and diameters and angles of surrounding parent and daughter vessels. Univariable and multivariable statistical analyses were performed to determine the association of morphological characteristics with rupture of MCA aneurysms. Logistic regression was used to build a predictive MCA score. Greater bottleneck and size ratio, and irregular, multilobed, temporally projecting MCA aneurysms are associated with higher rupture risk, whereas higher M1/M2 ratio, larger width, and the presence of an ipsilateral or bilateral hypoplastic PCoA were inversely associated with rupture. The MCA score had good predictive capacity with area under the receiver operating curve = 0.88. These practical morphological parameters specific to MCA aneurysms are easy to assess when examining 3D reconstructions of unruptured aneurysms and could aid in risk evaluation in these patients.

Delayed aneurysm rupture due to residual blood flow at the inflow zone of the intracranial paraclinoid internal carotid aneurysm treated with the Pipeline embolization device: Histopathological investigation

PubMed Central

Ikeda, Hiroyuki; Kikuchi, Takayuki; Ando, Mitsushige; Chihara, Hideo; Arai, Daisuke; Hattori, Etsuko; Miyamoto, Susumu

2015-01-01

Cerebral aneurysm rupture is a serious complication that can occur after flow diverter (FD) placement, but the underlying mechanisms remain unclear. We encountered a case in which direct stress on the aneurysm wall caused by residual blood flow at the inflow zone near the neck during the process of thrombosis after FD placement appeared associated with aneurysm rupture. The patient was a 67-year-old woman with progressive optic nerve compression symptoms caused by a large intracranial paraclinoid internal carotid aneurysm. The patient had undergone treatment with a Pipeline embolization device (PED) with satisfactory adherence between the PED and vessel wall. Surgery was completed without complications, and optic nerve compression symptoms improved immediately after treatment. Postoperative clinical course was satisfactory, but the patient suddenly died 34 days postoperatively. Autopsy confirmed the presence of subarachnoid hemorrhage caused by rupture of the internal carotid aneurysm that had been treated with PED. Although the majority of the aneurysm lumen including the outflow zone was thrombosed, a non-thrombosed area was observed at the inflow zone. Perforation was evident in the aneurysm wall at the inflow zone near the neck, and this particular area of aneurysm wall was not covered in thrombus. Macrophage infiltration was not seen on immunohistochemical studies of the aneurysm wall near the perforation. A hemodynamically unstable period during the process of complete thrombosis of the aneurysm lumen after FD placement may be suggested, and blood pressure management and appropriate management with antiplatelet therapy may be important. PMID:26500232

A Comparative Study of Different Hypothermic Circulatory Arrest Strategies on Aortic Surgery.

ClinicalTrials.gov

2018-03-22

Morality; Hypothermic Circulatory Arrest Time; Aortic-cross Clamping Time; Cardiopulmonary Bypass Time; Operation Time; Re-Thoracotomy; ICU Stay; Mechanical Ventilation Time; Blood Transfusion; Neurological Disorder; Dialysis; Aneurysm; Endoleak; Hospital Stay

Analysis of Surgical Freedom Variation Across the Basilar Artery Bifurcation: Towards a Deeper Insight Into Approach Selection for Basilar Apex Aneurysms.

PubMed

Tayebi Meybodi, Ali; Benet, Arnau; Rodriguez Rubio, Roberto; Yousef, Sonia; Lawton, Michael T

2018-03-03

The orbitozygomatic approach is generally advocated over the pterional approach for basilar apex aneurysms. However, the impact of the extensions of the pterional approach on the obtained maneuverability over multiple vascular targets (relevant to basilar apex surgery) has not been studied before. To analyze the patterns of surgical freedom change across the basilar bifurcation between the pterional, orbitopterional, and orbitozygomatic approaches. Surgical freedom was assessed for 3 vascular targets important in basilar apex aneurysm surgery (ipsilateral and contralateral P1-P2 junctions, and basilar apex), and compared between the pterional, orbitopterional, and orbitozygomatic approaches in 10 cadaveric specimens. Transitioning from the pterional to orbitopterional approach, the surgical freedom increased significantly at all 3 targets (P < .05). However, the gain in surgical freedom declined progressively from the most superficial target (60% for ipsilateral P1-P2 junction) to the deepest target (35% for contralateral P1-P2 junction). Conversely, transitioning from the orbitopterional to the orbitozygomatic approach, the gain in surgical freedom was minimal for the ipsilateral P1-P2 and basilar apex (<4%), but increased dramatically to 19% at the contralateral P1-P2 junction. The orbitopterional approach provides a remarkable increase in surgical maneuverability compared to the pterional approach for the basilar apex target and the relevant adjacent arterial targets. However, compared to the orbitopterional, the orbitozygomatic approach adds little maneuverability except for the deepest target (ie, contralateral P1-P2 junction). Therefore, the orbitozygomatic approach may be most efficacious with larger basilar apex aneurysms limiting the control over of the contralateral P1 PCA.

In Vitro Measurement of Tissue Integrity during Saccular Aneurysm Embolizations for Simulator-Based Training

PubMed Central

Tercero, C.; Ikeda, S.; Ooe, K.; Fukuda, T.; Arai, F.; Negoro, M.; Takahashi, I.; Kwon, G.

2012-01-01

Summary In the domain of endovascular neurosurgery, the measurement of tissue integrity is needed for simulator-based training and for the development of new intravascular instruments and treatment techniques. In vitro evaluation of tissue manipulation can be achieved using photoelastic stress analysis and vasculature modeling with photoelastic materials. In this research we constructed two types of vasculature models of saccular aneurysms for differentiation of embolization techniques according to the respect for tissue integrity measurements based on the stress within the blood vessel model wall. In an aneurysm model with 5 mm dome diameter, embolization using MicroPlex 10 (Complex 1D, with 4 mm diameter loops), a maximum area of 3.97 mm2 with stress above 1 kPa was measured. This area increased to 5.50 mm2 when the dome was touched deliberately with the release mechanism of the coil, and to 4.87 mm2 for an embolization using Micrusphere, (Spherical 18 Platinum Coil). In a similar way trans-cell stent-assisted coil embolization was also compared to human blood pressure simulation using a model of a wide-necked saccular aneurysm with 7 mm diameter. The area with stress above 1kPa was below 1 mm2 for the pressure simulation and maximized at 3.79 mm2 during the trans-cell insertion of the micro-catheter and at 8.92 mm2 during the embolization. The presented results show that this measurement system is useful for identifying techniques compromising tissue integrity, comparing and studying coils and embolization techniques for a specific vasculature morphology and comparing their natural stress variations such as that produced by blood pressure. PMID:23217635

Computational fluid dynamics (CFD) using porous media modeling predicts recurrence after coiling of cerebral aneurysms

PubMed Central

Ishida, Fujimaro; Tsuji, Masanori; Furukawa, Kazuhiro; Shiba, Masato; Yasuda, Ryuta; Toma, Naoki; Sakaida, Hiroshi; Suzuki, Hidenori

2017-01-01

Objective This study aimed to predict recurrence after coil embolization of unruptured cerebral aneurysms with computational fluid dynamics (CFD) using porous media modeling (porous media CFD). Method A total of 37 unruptured cerebral aneurysms treated with coiling were analyzed using follow-up angiograms, simulated CFD prior to coiling (control CFD), and porous media CFD. Coiled aneurysms were classified into stable or recurrence groups according to follow-up angiogram findings. Morphological parameters, coil packing density, and hemodynamic variables were evaluated for their correlations with aneurysmal recurrence. We also calculated residual flow volumes (RFVs), a novel hemodynamic parameter used to quantify the residual aneurysm volume after simulated coiling, which has a mean fluid domain > 1.0 cm/s. Result Follow-up angiograms showed 24 aneurysms in the stable group and 13 in the recurrence group. Mann-Whitney U test demonstrated that maximum size, dome volume, neck width, neck area, and coil packing density were significantly different between the two groups (P < 0.05). Among the hemodynamic parameters, aneurysms in the recurrence group had significantly larger inflow and outflow areas in the control CFD and larger RFVs in the porous media CFD. Multivariate logistic regression analyses demonstrated that RFV was the only independently significant factor (odds ratio, 1.06; 95% confidence interval, 1.01–1.11; P = 0.016). Conclusion The study findings suggest that RFV collected under porous media modeling predicts the recurrence of coiled aneurysms. PMID:29284057

Efficacy Analysis of a Script-based Guide for EVAR Execution: is it Possible to Reduce Patient Exposure to Contrast, Operative Time and Blood Loss even when Advanced Technologies are not Available?

PubMed

Molinari, Giovani José Dal Poggetto; Guillaumon, Ana Terezinha; Dalbem, Andréia Marques de Oliveira

2015-01-01

Despite the patient and medical staff exposure to radiation in endovascular aneurysm repair, the benefits of this abdominal aortic aneurysm type of surgical management are justified by minor recovery time and hospitalization, as well as an option for patients not elected to conventional open repair. In this minimally invasive surgical approach, time of procedure and radiation doses can be substantial--and the increasing frequency of these procedures and it's complexity have impelled vascular surgeons to face additional and successive risk to occupational radiation exposure. Meticulous study of the computed tomography angiography during the endovascular aneurysm repair preparation allows reduction of unnecessary radiation exposure, as also reduces consecutive image acquisition and contrast use (that may be related to renal overload in susceptible patients). Some studies have proposed strategies to optimize endovascular intervention to reduce contrast use and X-ray exposure. Although they might prove to be effective, they rely on use of additional specific and advanced equipment, available only in major centers. As an alternative to this expensive and restrict technology, it is presented a simpler technique through image manipulation on software OsiriX, aiming to reduce both exposures. To analyze the efficacy of the adoption of a study protocol and a script-based guide in preparation for endovascular aneurysm repair through verifying its impact over the surgical procedure--as referred to intravascular contrast infuse, effects over renal function, blood loss and operatory time. A longitudinal prospective study from March 2014 through March 2015, where 30 performed endovascular aneurysm repair were compared to a historic control group. The planning for endovascular aneurysm repair through the patient's tomographic image manipulation in the prospective group was performed with OsiriX MD software. A script-based guide upon gathering detailed computed tomography angiography images was elaborated by the author and distributed to the performing surgical team for appreciation, instruction and pre operatory judgment. Based upon the script, the C-arm gantry angle was specifically corrected in each case of endovascular aneurysm repair, for image optimization and aneurysm's neck visualization. Arteriography was performed under digital subtraction angiography after catheters were positioned according to predicted level description in the referred guide. Statistical analysis were performed with a significance level of 5% (P value<0.05). There was a statistically significant relationship between the two studied periods and the variables: contrast volume (284.5 vs. 31.8 mL), operative time (207.5 vs. 140.4 min.) and blood loss (798.1 vs. 204.4 mL), revealing that they are considerably larger in the historical control group than in the script guided current group. There was no difference related to the volume of contrast used in the two groups and the occurrence of renal impairment. In the present paper it was possible to demonstrate the impact of the ability to manipulate digital formats of medical images without the need of sophisticated equipment, in adoption of a guide based on the compilation of informations collected with assistance of an accessible software performed on a personal computer. Although we could not prove relation to occurrence of renal impairment, there were direct results on reduction of intravascular contrast use, even as surgical time and blood loss, compared to a previous historical period.

Reversal of Vascular Calcification and Aneurysms in a Rat Model Using Dual Targeted Therapy with EDTA- and PGG-Loaded Nanoparticles

PubMed Central

Nosoudi, Nasim; Chowdhury, Aniqa; Siclari, Steven; Karamched, Saketh; Parasaram, Vaideesh; Parrish, Joe; Gerard, Patrick; Vyavahare, Narendra

2016-01-01

Degeneration of elastic lamina and vascular calcification are common features of vascular pathology such as aortic aneurysms. We tested whether dual therapy with targeted nanoparticles (NPs) can remove mineral deposits (by delivery of a chelating agent, ethylene diamine tetraacetic acid (EDTA)) and restore elastic lamina (by delivery of a polyphenol, pentagalloyl glucose (PGG)) to reverse moderate aneurysm development. EDTA followed by PGG NP delivery led to reduction in macrophage recruitment, matrix metalloproteinase (MMP) activity, elastin degradation and calcification in the aorta as compared to delivery of control blank NPs. Such dual therapy restored vascular elastic lamina and improved vascular function as observed by improvement in circumferential strain. Therefore, dual targeted therapy may be an attractive option to remove mineral deposits and restore healthy arterial structures in moderately developed aneurysms. PMID:27698934

Aneurysm

MedlinePlus

Aneurysm - splenic artery; Aneurysm - popliteal artery; Aneurysm - mesenteric artery ... It is not clear exactly what causes aneurysms. Some aneurysms are ... the artery wall may be a cause. Common locations for aneurysms ...

Medical Treatment of Aortic Aneurysms in Marfan Syndrome and other Heritable Conditions

PubMed Central

Jost, Christine H. Attenhofer; Greutmann, Matthias; Connolly, Heidi M.; Weber, Roland; Rohrbach, Marianne; Oxenius, Angela; Kretschmar, Oliver; Luscher, Thomas F.; Matyas, Gabor

2014-01-01

Thoracic aortic aneurysms can be triggered by genetic disorders such as Marfan syndrome (MFS) and related aortic diseases as well as by inflammatory disorders such as giant cell arteritis or atherosclerosis. In all these conditions, cardiovascular risk factors, such as systemic arterial hypertension, may contribute to faster rate of aneurysm progression. Optimal medical management to prevent progressive aortic dilatation and aortic dissection is unknown. β-blockers have been the mainstay of medical treatment for many years despite limited evidence of beneficial effects. Recently, losartan, an angiotensin II type I receptor antagonist (ARB), has shown promising results in a mouse model of MFS and subsequently in humans with MFS and hence is increasingly used. Several ongoing trials comparing losartan to β-blockers and/or placebo will better define the role of ARBs in the near future. In addition, other medications, such as statins and tetracyclines have demonstrated potential benefit in experimental aortic aneurysm studies. Given the advances in our understanding of molecular mechanisms triggering aortic dilatation and dissection, individualized management tailored to the underlying genetic defect may be on the horizon of individualized medicine. We anticipate that ongoing research will address the question whether such genotype/pathogenesis-driven treatments can replace current phenotype/syndrome-driven strategies and whether other forms of aortopathies should be treated similarly. In this work, we review currently used and promising medical treatment options for patients with heritable aortic aneurysmal disorders. PMID:24527681

Treatment of Brain Arteriovenous Malformations with Hemodynamic Aneurysms: A Series of 131 Consecutive Cases.

PubMed

Eliava, Shalva; Dmitriev, Alexey; Shekhtman, Oleg; Yakovlev, Sergey; Kheireddin, Ali; Pilipenko, Yuriy

2018-02-01

The natural history of hemodynamic aneurysms (HAs) associated with brain arteriovenous malformations (AVMs) remains controversial, with no single approach to treatment. The purpose of this study was to justify preventive treatment tactics for HAs that pose an increased risk of rupture based on hemodynamic studies demonstrating hypertension in the afferent bed after AVM exclusion. This retrospective analysis included 131 of 1740 patients (8%) with brain AVMs and at least 1 aneurysm treated at Burdenko Neurosurgical Institute between 2000 and 2016. Treatment consisted of microsurgery, endovascular interventions, or a combination of modalities. Patients were evaluated with the modified Rankin Scale before and after treatment. A total of 205 aneurysms were discovered. Multiple HAs were found in 46 patients (35%), and were significantly more often associated with posterior fossa AVMs; in addition, most were distally located. There was no difference in the incidence of hemorrhage between proximal and distal HAs. Microsurgical treatment was marked by high radicalism; 85% of HAs and 94% of AVMs were totally excluded based on control studies. In 10 cases, aneurysms were found after AVM removal, including 4 de novo aneurysms. In 1 case, the aneurysm regressed after AVM treatment. The mortality rate was 2.3%. Preoperative imaging should be carefully examined for associated aneurysms before and after surgical treatment. Our data suggests that HA exclusion, either as the first step or simultaneously with AVM treatment, is most beneficial to patients. Copyright © 2017 Elsevier Inc. All rights reserved.

Ruptured Distal Posterior Inferior Cerebellar Artery (PICA) Aneurysms Associated with Cerebellar Arterial Venous Malformations (AVMs): A Case Series and Review of the Literature Demonstrating the Need for Angiographic Evaluation and Feasibility of Endovascular Treatment.

PubMed

Case, David; Kumpe, David; Cava, Luis; Neumann, Robert; White, Andrew; Roark, Christopher; Seinfeld, Joshua

2017-01-01

The characteristics, diagnosis, and preferred management strategies for distal posterior inferior cerebellar artery (PICA) aneurysms associated with cerebellar arteriovenous malformation (AVMs) are poorly understood. We present a case series with attention to aneurysm angioarchitecture, diagnostic imaging, treatment approaches, and a thorough review of the literature. With this information, we demonstrate a specific anatomical pattern for these aneurysms, an underreported need for conventional digital subtraction angiography (DSA) during evaluation, along with the utility of endovascular treatment with liquid embolic agents. Neurosurgical patients from 2005 to 2016 were reviewed to identify PICA aneurysms along with distal PICA aneurysms. Details of their presentation, imaging studies, associated AVMs and treatment were recorded. A thorough literature search of previous case series and case reports of distal PICA aneurysms with and without associated small cerebellar AVMs was performed with PubMed and Google Scholar. Thirty-four patients with PICA aneurysms were identified at our institution, 12 of which were in a distal segment. All 12 of these patients underwent DSA as a part of their evaluation. Of the 12 patients with distal PICA aneurysms, 9 presented with subarachnoid hemorrhage and intraventricular hemorrhage. Five of these patients had a small occult cerebellar AVM. All nine patients presenting with a ruptured distal PICA aneurysm had a Fischer grade 4 subarachnoid hemorrhage. Of the five patients with a small occult cerebellar AVM, the AVM nidus was missed on computed tomography angiogram (CTA) interpretation but easily visualized with DSA. CTA followed by DSA with concurrent endovascular treatment was performed in 9 of the 12 patients with distal PICA aneurysms. Two of the 12 patients were treated with microsurgical clip ligation, and one mycotic aneurysm was identified and treated with antibiotics. Parent vessel sacrifice was used distal to the aneurysm in all 5 associated AVM cases with liquid embolic agents as well as AVM embolization in 3 of the 5 cases. Fifty-one well-described case reports of distal PICA aneurysms associated with small cerebellar AVMs have been reported in the literature. A total of 12 well-described case series of distal PICA aneurysms that comment on associated AVMs describe an associated small cerebellar AVM incidence of 4%-50%. In our case series, the incidence of an associated small cerebellar AVM with a distal PICA aneurysm was 42%. In cases of distal PICA aneurysms, there is a frequent association of a small cerebellar AVM. In our series, CTA was an inadequate diagnostic study to identify the associated AVM, and DSA was necessary to definitely visualize the AVM nidus. Endovascular treatment of the aneurysm and AVM with the use of liquid embolic agents was a feasible and useful management strategy. Copyright © 2016 Elsevier Inc. All rights reserved.

Endovascular Management of Ruptured Pancreaticoduodenal Artery Aneurysms Associated with Celiac Axis Stenosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suzuki, Kojiro, E-mail: Kojiro@med.nagoya-u.ac.jp; Tachi, Yasushi; Ito, Shinji

2008-11-15

The purpose of this study was to assess the efficacy of transcatheter arterial embolization for ruptured pancreaticoduodenal artery (PDA) aneurysms associated with celiac axis stenosis (CS). Seven patients (four men and three women; mean age, 64; range, 43-84) were treated with transcatheter arterial embolization between 2002 and 2007. They were analyzed with regard to the clinical presentation, radiological finding, procedure, and outcome. All patients presented with sudden epigastric pain or abdominal discomfort. Contrast-enhanced CT showed a small aneurysm and retroperitoneal hematoma around the pancreatic head in all patients. The aneurysms ranged from 0.3 to 0.9 cm in size. In onemore » patient, two aneurysms were detected. The aneurysms were located in the pancreaticoduodenal artery (n = 5) and the dorsal pancreatic artery (n = 3). Embolization was performed with microcoils in all aneurysms (n = 8). N-Butyl 2-cyanoacrylate (n = 1) and gelatine particle (n = 1) were also used. Complete occlusion was achieved in four patients. In the other three patients, a significantly reduced flow to the aneurysm remained at final angiography. However, these aneurysms were thrombosed on follow-up CT within 2 weeks. And there was no recurrence of the symptoms and bleeding during follow-up (mean, 28 months; range, 5-65 months) in all patients. In conclusion, transcatheter arterial embolization for PDA aneurysms associated with CS is effective. Significant reduction of the flow to the aneurysm at final angiography may be predictive of future thrombosis.« less

Update on the prevention of death from ruptured abdominal aortic aneurysm.

PubMed

Jacomelli, Jo; Summers, Lisa; Stevenson, Anne; Lees, Tim; Earnshaw, Jonothan J

2017-09-01

Objectives To monitor the early effect of a national population screening programme for abdominal aortic aneurysm in 65-year-old men. Setting The study used national statistics for death rates from abdominal aortic aneurysm (Office of National Statistics) and hospital admission data in England (Hospital Episode Statistics). Methods Information concerning deaths from abdominal aortic aneurysm (ruptured and non-ruptured) (1999-2014) and hospital admissions for ruptured abdominal aortic aneurysm (2000-2015) was examined. Results The absolute number of deaths from abdominal aortic aneurysm in men and women aged 65 and over has decreased by around 30% from 2001 to 2014, but as the population has increased, the relative reduction was 45.6% and 40.0%, respectively. Some 65% of all abdominal aortic aneurysm deaths are in men aged over 65; women aged 65 and over account for around 31%. Deaths from ruptured abdominal aortic aneurysm in men aged 60-74 (the screened group) appear to be declining at the same rate as in men aged 75 and over. The relative decline in admissions to hospital with ruptured abdominal aortic aneurysm may be greater in men and women aged 60-74 (which contains the screened group of men), than those older, giving the first possible evidence that abdominal aortic aneurysm screening is having an effect. Conclusion The death rate from abdominal aortic aneurysm is declining rapidly in England. There is the first evidence that screening may be contributing to this reduction.

Canadian experience with the pipeline embolization device for repair of unruptured intracranial aneurysms.

PubMed

O'Kelly, C J; Spears, J; Chow, M; Wong, J; Boulton, M; Weill, A; Willinsky, R A; Kelly, M; Marotta, T R

2013-02-01

Flow-diverting stents, such as the PED, have emerged as a novel means of treating complex intracranial aneurysms. This retrospective analysis of the initial Canadian experience provides insight into technical challenges, clinical and radiographic outcomes, and complication rates after the use of flow-diverting stents for unruptured aneurysms. Cases were compiled from 7 Canadian centers between July 2008 and December 2010. Each center prospectively tracked their initial experience; these data were retrospectively updated and pooled for analysis. During the defined study period, 97 cases of unruptured aneurysm were treated with the PED, with successful stent deployment in 94 cases. The overall complete or near-complete occlusion rate was 83%, with a median follow-up at 1.25 years (range 0.25-2.5 years). Progressive occlusion was witnessed over time, with complete or near-complete occlusion in 65% of aneurysms followed through 6 months, and 90% of aneurysms followed through 1 year. Multivariate analysis found previous aneurysm treatment and female sex predictive of persistent aneurysm filling. Most patients were stable or improved (88%), with the most favorable outcomes observed in patients with cavernous carotid aneurysms. The overall mortality rate was 6%. Postprocedural aneurysm hemorrhage occurred in 3 patients (3%), while ipsilateral distal territory hemorrhage was observed in 4 patients (3.4%). Flow-diverting stents represent an important tool in the treatment of complex intracranial aneurysms. The relative efficacy and morbidity of this treatment must be considered in the context of available alternate interventions.

Flow-independent dynamics in aneurysm (FIDA): pressure measurements following partial and complete flow impairment in experimental aneurysm model

PubMed Central

Watanabe, Masaki; Chaudhry, Saqib A; Qureshi, Adnan I

2014-01-01

Background: There have been growing concerns regarding delayed aneurysm rupture subsequent to the flow-diverting stent deployment. Therefore, more investigations are needed regarding hemodynamic changes secondary to flow-diverting stent deployment. Objective: To study intra-aneurysmal and perianeurysmal pressures after partial and complete flow impairment into the aneurysm. Methods A silicone model of an 8-mm-sized aneurysm (neck diameter: 5 mm, vessel size: 4 mm) was used. The aneurysm wall was encapsulated and sealed within a 5 ml syringe filled with saline and a pressure sensor guide wire (ComboWire, Volcano Corp.) to detect pressure changes in the perivascular compartment (outer aneurysm wall). A second pressure sensor guide wire was advanced inside the aneurysm sac. Both pressure sensors were continuously measuring pressure inside and outside the aneurysm under pulsatile flow under the following conditions: 1) baseline (reference); 2) a 16 mm by 3.75 mm flow-diverting stent (ev3/Covidien Vascular, Mansfield, MA) deployed in front of the aneurysm; 3) two flow-diverting stents (16 mm by 3.5 mm) were deployed; and 4) a covered stent (4 mm by 16 mm VeriFlex coronary artery stent covered with rubber sheet) was deployed. Results: Mean (±SD) baseline pressures inside and outside the aneurysm were 53.9 (±2.4) mmHg (range 120–40 mmHg) and 15.4 (±0.7) mmHg (range 40–8mmHg), respectively. There was no change in pressure inside and outside the aneurysm after deploying the first and second flow-diverting stents (partial flow impairment) and it remained at 53.9 (±2.7) mmHg and 14.9 (±1) mmHg for the pressure inside and outside the aneurysm, respectively. The pressure recording from outside the aneurysm dropped from 15.4 (±0.7) mmHg to 0.3 (±0.7) mmHg after deploying the covered stent (complete flow impairment). There was no change in pressure inside the aneurysm after deploying the covered stent. Mean (±SD) pressure within the aneurysm was 55.1 (±1.7) mmHg and it remained 54.7 (±1.7) mmHg after covered stent deployment. Conclusion: Our findings suggest a major discordance between the pressures within the aneurysm and partial or complete flow impairment (flow independent). The outer wall pressure is reduced after covered stent placement. These finding may assist clinicians in better understanding of aneurysm hemodynamics and rupture after flow-diverting stent deployment. PMID:25298859

Testing flow diversion in animal models: a systematic review.

PubMed

Fahed, Robert; Raymond, Jean; Ducroux, Célina; Gentric, Jean-Christophe; Salazkin, Igor; Ziegler, Daniela; Gevry, Guylaine; Darsaut, Tim E

2016-04-01

Flow diversion (FD) is increasingly used to treat intracranial aneurysms. We sought to systematically review published studies to assess the quality of reporting and summarize the results of FD in various animal models. Databases were searched to retrieve all animal studies on FD from 2000 to 2015. Extracted data included species and aneurysm models, aneurysm and neck dimensions, type of flow diverter, occlusion rates, and complications. Articles were evaluated using a checklist derived from the Animal Research: Reporting of In Vivo Experiments (ARRIVE) guidelines. Forty-two articles reporting the results of FD in nine different aneurysm models were included. The rabbit elastase-induced aneurysm model was the most commonly used, with 3-month occlusion rates of 73.5%, (95%CI [61.9-82.6%]). FD of surgical sidewall aneurysms, constructed in rabbits or canines, resulted in high occlusion rates (100% [65.5-100%]). FD resulted in modest occlusion rates (15.4% [8.9-25.1%]) when tested in six complex canine aneurysm models designed to reproduce more difficult clinical contexts (large necks, bifurcation, or fusiform aneurysms). Adverse events, including branch occlusion, were rarely reported. There were no hemorrhagic complications. Articles complied with 20.8 ± 3.9 of 41 ARRIVE items; only a small number used randomization (3/42 articles [7.1%]) or a control group (13/42 articles [30.9%]). Preclinical studies on FD have shown various results. Occlusion of elastase-induced aneurysms was common after FD. The model is not challenging but standardized in many laboratories. Failures of FD can be reproduced in less standardized but more challenging surgical canine constructions. The quality of reporting could be improved.

Influence of warfarin therapy on the occurrence of postoperative endoleaks and aneurysm sac enlargement after endovascular abdominal aortic aneurysm repair.

PubMed

Seike, Yoshimasa; Tanaka, Hiroshi; Fukuda, Tetsuya; Itonaga, Tatsuya; Morita, Yoshiaki; Oda, Tatsuya; Inoue, Yosuke; Sasaki, Hiroaki; Minatoya, Kenji; Kobayashi, Junjiro

2017-04-01

This study aims to determine whether warfarin therapy influences the occurrence of endoleaks or aneurysm sac enlargement after endovascular aortic repair (EVAR). A total of 367 patients who underwent EVAR for abdominal aortic aneurysm between 2007 and 2013 were recruited for this study. Satisfactory follow-up data including completed computed tomography scan follow-up for more than 2 years were available for 209 patients, and the mean follow-up time was 37 ± 12 months. Twenty-nine (16%) patients were on warfarin therapy (warfarin group), whereas 180 (84%) patients were not on warfarin therapy (control group). Two- and four-year freedom rates for persistent type II endoleaks were significantly lower in patients of the warfarin group compared with the control group (85 and 49% vs 93 and 91%, respectively; P = 0.0001). Similarly, 2- and 4-year freedom rates for sac enlargement (>5 mm) were significantly lower in patients of the warfarin group compared with the control group (83 and 61% vs 92 and 82%, respectively; P = 0.0036). Using Cox regression analysis, the warfarin therapy was identified to be an independent positive predictor of sac enlargement after EVAR [hazard ratio (HR): 2.4; 95% confidence interval (CI): 1.08-5.40; P = 0.032], together with persistent type II endoleak. Warfarin therapy was also an independent predictor for persistent type II endoleak (HR: 3.7; 95% CI: 1.81-7.41; P < 0.0001) together with the number of patent lumbar arteries. Results suggested that warfarin therapy was significantly associated with an increased risk for persistent II endoleak and sac enlargement after EVAR. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Non-contrast 3D time-of-flight magnetic resonance angiography for visualization of intracranial aneurysms in patients with absolute contraindications to CT or MRI contrast.

PubMed

Yanamadala, Vijay; Sheth, Sameer A; Walcott, Brian P; Buchbinder, Bradley R; Buckley, Deidre; Ogilvy, Christopher S

2013-08-01

The preoperative evaluation of patients with intracranial aneurysms typically includes a contrast-enhanced vascular study, such as computed tomography angiography (CTA), magnetic resonance angiography (MRA), or digital subtraction angiography. However, there are numerous absolute and relative contraindications to the administration of imaging contrast agents, including pregnancy, severe contrast allergy, and renal insufficiency. Evaluation of patients with contrast contraindications thus presents a unique challenge. We identified three patients with absolute contrast contraindications who presented with intracranial aneurysms. One patient was pregnant, while the other two had previous severe anaphylactic reactions to iodinated contrast. Because of these contraindications to intravenous contrast, we performed non-contrast time-of-flight MRA with 3D reconstruction (TOF MRA with 3DR) with maximum intensity projections and volume renderings as part of the preoperative evaluation prior to successful open surgical clipping of the aneurysms. In the case of one paraclinoid aneurysm, a high-resolution non-contrast CT scan was also performed to assess the relationship of the aneurysm to the anterior clinoid process. TOF MRA with 3DR successfully identified the intracranial aneurysms and adequately depicted the surrounding microanatomy. Intraoperative findings were as predicted by the preoperative imaging studies. The aneurysms were successfully clip-obliterated, and the patients had uneventful post-operative courses. These cases demonstrate that non-contrast imaging is a viable modality to assess intracranial aneurysms as part of the surgical planning process in patients with contrast contraindications. TOF MRA with 3DR, in conjunction with high-resolution non-contrast CT when indicated, provides adequate visualization of the microanatomy of the aneurysm and surrounding structures. Copyright © 2013 Elsevier Ltd. All rights reserved.

Vascular wall flow-induced forces in a progressively enlarged aneurysm model.

PubMed

Neofytou, Panagiotis; Tsangaris, Sokrates; Kyriakidis, Michalis

2008-12-01

The current study is focused on the numerical investigation of the flow field induced by the unsteady flow in the vicinity of an abdominal aortic aneurysm model. The computational fluid dynamics code used is based on the finite volume method, and it has already been used in various bioflow studies. For modelling the rheological behaviour of blood, the Quemada non-Newtonian model is employed, which is suitable for simulating the two-phase character of blood namely a suspension of blood cells in plasma. For examining its non-Newtonian effects a comparison with a corresponding Newtonian flow is carried out. Furthermore, the investigation is focused on the distribution of the flow-induced forces on the interior wall of the aneurysm and in order to study the development of the distribution with the gradual enlargement of the aneurysm, three different degrees of aneurysm-growth have been assumed. Finally and for examining the effect of the distribution on the aneurysm growth, a comparison is made between the pressure and wall shear-stress distributions at the wall for each growth-degree.

Computerized detection of unruptured aneurysms in MRA images: reduction of false positives using anatomical location features

NASA Astrophysics Data System (ADS)

Uchiyama, Yoshikazu; Gao, Xin; Hara, Takeshi; Fujita, Hiroshi; Ando, Hiromichi; Yamakawa, Hiroyasu; Asano, Takahiko; Kato, Hiroki; Iwama, Toru; Kanematsu, Masayuki; Hoshi, Hiroaki

2008-03-01

The detection of unruptured aneurysms is a major subject in magnetic resonance angiography (MRA). However, their accurate detection is often difficult because of the overlapping between the aneurysm and the adjacent vessels on maximum intensity projection images. The purpose of this study is to develop a computerized method for the detection of unruptured aneurysms in order to assist radiologists in image interpretation. The vessel regions were first segmented using gray-level thresholding and a region growing technique. The gradient concentration (GC) filter was then employed for the enhancement of the aneurysms. The initial candidates were identified in the GC image using a gray-level threshold. For the elimination of false positives (FPs), we determined shape features and an anatomical location feature. Finally, rule-based schemes and quadratic discriminant analysis were employed along with these features for distinguishing between the aneurysms and the FPs. The sensitivity for the detection of unruptured aneurysms was 90.0% with 1.52 FPs per patient. Our computerized scheme can be useful in assisting the radiologists in the detection of unruptured aneurysms in MRA images.

Vortex dynamics in ruptured and unruptured intracranial aneurysms

NASA Astrophysics Data System (ADS)

Trylesinski, Gabriel; Varble, Nicole; Xiang, Jianping; Meng, Hui

2013-11-01

Intracranial aneurysms (IAs) are potentially devastating pathological dilations of arterial walls that affect 2-5% of the population. In our previous CFD study of 119 IAs, we found that ruptured aneurysms were correlated with complex flow pattern and statistically predictable by low wall shear stress and high oscillatory shear index. To understand flow mechanisms that drive the pathophysiology of aneurysm wall leading to either stabilization or growth and rupture, we aim at exploring vortex dynamics of aneurysmal flow and provide insight into the correlation between the previous predictive morphological parameters and wall hemodynamic metrics. We adopt the Q-criterion definition of coherent structures (CS) and analyze the CS dynamics in aneurysmal flows for both ruptured and unruptured IA cases. For the first time, we draw relevant biological conclusions concerning aneurysm flow mechanisms and pathophysiological outcome. In pulsatile simulations, the coherent structures are analyzed in these 119 patient-specific geometries obtained using 3D angiograms. The images were reconstructed and CFD were performed. Upon conclusion of this work, better understanding of flow patterns of unstable aneurysms may lead to improved clinical outcome.

Physiological remodeling of bifurcation aneurysms: preclinical results of the eCLIPs device.

PubMed

Marotta, Thomas R; Riina, Howard A; McDougall, Ian; Ricci, Donald R; Killer-Oberpfalzer, Monika

2018-02-01

OBJECTIVE Intracranial bifurcation aneurysms are complex lesions for which current therapy, including simple coiling, balloon- or stent-assisted coiling, coil retention, or intrasaccular devices, is inadequate. Thromboembolic complications due to a large burden of intraluminal metal, impedance of access to side branches, and a high recurrence rate, due largely to the unmitigated high-pressure flow into the aneurysm (water hammer effect), are among the limitations imposed by current therapy. The authors describe herein a novel device, eCLIPs, and its use in a preclinical laboratory study that suggests the device's design and functional features may overcome many of these limitations. METHODS A preclinical model of wide-necked bifurcation aneurysms in rabbits was used to assess functional features and efficacy of aneurysm occlusion by the eCLIPs device. RESULTS The eCLIPs device, in bridging the aneurysm neck, allows coil retention, disrupts flow away from the aneurysm, leaves the main vessel and side branches unencumbered by intraluminal metal, and serves as a platform for endothelial growth across the neck, excluding the aneurysm from the circulation. CONCLUSIONS The eCLIPs device permits physiological remodeling of the bifurcation.

Physical Factors Effecting Cerebral Aneurysm Pathophysiology

PubMed Central

Sadasivan, Chander; Fiorella, David J.; Woo, Henry H.; Lieber, Baruch B.

2013-01-01

Many factors that are either blood-, wall-, or hemodynamics-borne have been associated with the initiation, growth, and rupture of intracranial aneurysms. The distribution of cerebral aneurysms around the bifurcations of the circle of Willis has provided the impetus for numerous studies trying to link hemodynamic factors (flow impingement, pressure, and/or wall shear stress) to aneurysm pathophysiology. The focus of this review is to provide a broad overview of such hemodynamic associations as well as the subsumed aspects of vascular anatomy and wall structure. Hemodynamic factors seem to be correlated to the distribution of aneurysms on the intracranial arterial tree and complex, slow flow patterns seem to be associated with aneurysm growth and rupture. However, both the prevalence of aneurysms in the general population and the incidence of ruptures in the aneurysm population are extremely low. This suggests that hemodynamic factors and purely mechanical explanations by themselves may serve as necessary, but never as necessary and sufficient conditions of this disease’s causation. The ultimate cause is not yet known, but it is likely an additive or multiplicative effect of a handful of biochemical and biomechanical factors. PMID:23549899

Logistic considerations for a successful institutional approach to the endovascular repair of ruptured abdominal aortic aneurysms.

PubMed

Mayer, Dieter; Rancic, Zoran; Pfammatter, Thomas; Hechelhammer, Lukas; Veith, Frank J; Donas, Konstantin; Lachat, Mario

2010-01-01

The value of emergency endovascular aneurysm repair (EVAR) in the setting of ruptured abdominal aortic aneurysm remains controversial owing to differing results. However, interpretation of published results remains difficult as there is a lack of generally accepted protocols or standard operating procedures. Furthermore, such protocols and standard operating procedures often are reported incompletely or not at all, thereby making interpretation of results difficult. We herein report our integrated logistic system for the endovascular treatment of ruptured abdominal aortic aneurysms. Important components of this system are prehospital logistics, in-hospital treatment logistics, and aftercare. Further studies should include details about all of these components, and a description of these logistic components must be included in all future studies of emergency EVAR for ruptured abdominal aortic aneurysms.

Aortic Disease in the Young: Genetic Aneurysm Syndromes, Connective Tissue Disorders, and Familial Aortic Aneurysms and Dissections

PubMed Central

Cury, Marcelo; Zeidan, Fernanda; Lobato, Armando C.

2013-01-01

There are many genetic syndromes associated with the aortic aneurysmal disease which include Marfan syndrome (MFS), Ehlers-Danlos syndrome (EDS), Loeys-Dietz syndrome (LDS), familial thoracic aortic aneurysms and dissections (TAAD), bicuspid aortic valve disease (BAV), and autosomal dominant polycystic kidney disease (ADPKD). In the absence of familial history and other clinical findings, the proportion of thoracic and abdominal aortic aneurysms and dissections resulting from a genetic predisposition is still unknown. In this study, we propose the review of the current genetic knowledge in the aortic disease, observing, in the results that the causative genes and molecular pathways involved in the pathophysiology of aortic aneurysm disease remain undiscovered and continue to be an area of intensive research. PMID:23401778

Minimally Invasive Thumb-sized Pterional Craniotomy for Surgical Clip Ligation of Unruptured Anterior Circulation Aneurysms

PubMed Central

Deshaies, Eric M; Villwock, Mark R; Singla, Amit; Toshkezi, Gentian; Padalino, David J

2015-01-01

Less invasive surgical approaches for intracranial aneurysm clipping may reduce length of hospital stay, surgical morbidity, treatment cost, and improve patient outcomes. We present our experience with a minimally invasive pterional approach for anterior circulation aneurysms performed in a major tertiary cerebrovascular center and compare the results with an aged matched dataset from the Nationwide Inpatient Sample (NIS). From August 2008 to December 2012, 22 elective aneurysm clippings on patients ≤55 years of age were performed by the same dual fellowship-trained cerebrovascular/endovascular neurosurgeon. One patient (4.5%) experienced transient post-operative complications. 18 of 22 patients returned for follow-up imaging and there were no recurrences through an average duration of 22 months. A search in the NIS database from 2008 to 2010, also for patients aged ≤55 years of age, yielded 1,341 hospitalizations for surgical clip ligation of unruptured cerebral aneurysms. Inpatient length of stay and hospital charges at our institution using the minimally invasive thumb-sized pterional technique were nearly half that of NIS (length of stay: 3.2 vs 5.7 days; hospital charges: $52,779 vs. $101,882). The minimally invasive thumb-sized pterional craniotomy allows good exposure of unruptured small and medium-sized supraclinoid anterior circulation aneurysms. Cerebrospinal fluid drainage from key subarachnoid cisterns and constant bimanual microsurgical techniques avoid the need for retractors which can cause contusions, localized venous infarctions, and post-operative cerebral edema at the retractor sites. Utilizing this set of techniques has afforded our patients with a shorter hospital stay at a lower cost compared to the national average. PMID:26325337

IN VITRO QUANTIFICATION OF THE SIZE DISTRIBUTION OF INTRASACCULAR VOIDS LEFT AFTER ENDOVASCULAR COILING OF CEREBRAL ANEURYSMS.

PubMed

Sadasivan, Chander; Brownstein, Jeremy; Patel, Bhumika; Dholakia, Ronak; Santore, Joseph; Al-Mufti, Fawaz; Puig, Enrique; Rakian, Audrey; Fernandez-Prada, Kenneth D; Elhammady, Mohamed S; Farhat, Hamad; Fiorella, David J; Woo, Henry H; Aziz-Sultan, Mohammad A; Lieber, Baruch B

2013-03-01

Endovascular coiling of cerebral aneurysms remains limited by coil compaction and associated recanalization. Recent coil designs which effect higher packing densities may be far from optimal because hemodynamic forces causing compaction are not well understood since detailed data regarding the location and distribution of coil masses are unavailable. We present an in vitro methodology to characterize coil masses deployed within aneurysms by quantifying intra-aneurysmal void spaces. Eight identical aneurysms were packed with coils by both balloon- and stent-assist techniques. The samples were embedded, sequentially sectioned and imaged. Empty spaces between the coils were numerically filled with circles (2D) in the planar images and with spheres (3D) in the three-dimensional composite images. The 2D and 3D void size histograms were analyzed for local variations and by fitting theoretical probability distribution functions. Balloon-assist packing densities (31±2%) were lower ( p =0.04) than the stent-assist group (40±7%). The maximum and average 2D and 3D void sizes were higher ( p =0.03 to 0.05) in the balloon-assist group as compared to the stent-assist group. None of the void size histograms were normally distributed; theoretical probability distribution fits suggest that the histograms are most probably exponentially distributed with decay constants of 6-10 mm. Significant ( p <=0.001 to p =0.03) spatial trends were noted with the void sizes but correlation coefficients were generally low (absolute r <=0.35). The methodology we present can provide valuable input data for numerical calculations of hemodynamic forces impinging on intra-aneurysmal coil masses and be used to compare and optimize coil configurations as well as coiling techniques.

Polycystic kidney disease among 4,436 intracranial aneurysm patients from a defined population.

PubMed

Nurmonen, Heidi J; Huttunen, Terhi; Huttunen, Jukka; Kurki, Mitja I; Helin, Katariina; Koivisto, Timo; von Und Zu Fraunberg, Mikael; Jääskeläinen, Juha E; Lindgren, Antti E

2017-10-31

To define the association of autosomal dominant polycystic kidney disease (ADPKD) with the characteristics of aneurysmal subarachnoid hemorrhage (aSAH) and unruptured intracranial aneurysm (IA) disease. We fused data from the Kuopio Intracranial Aneurysm database (n = 4,436 IA patients) and Finnish nationwide registries into a population-based series of 53 IA patients with ADPKD to compare the aneurysm- and patient-specific characteristics of IA disease in ADPKD and in the general IA population, and to identify risks for de novo IA formation. In total, there were 33 patients with ADPKD with aSAH and 20 patients with ADPKD with unruptured IAs. The median size of ruptured IAs in ADPKD was significantly smaller than in the general population (6.00 vs 8.00 mm) and the proportion of small ruptured IAs was significantly higher (31% vs 18%). Median age at aSAH was 42.8 years, 10 years younger than in the general IA population. Multiple IAs were present in 45% of patients with ADPKD compared to 28% in the general IA population. Cumulative risk of de novo IA formation was 1.3% per patient-year (vs 0.2% in the general IA population). Hazard for de novo aneurysm formation was significantly elevated in patients with ADPKD (Cox regression hazard ratio 7.7, 95% confidence interval 2.8-20; p < 0.0005). Subarachnoid hemorrhage occurs at younger age and from smaller IAs in patients with ADPKD and risk for de novo IAs is higher than in the general Eastern Finnish population. ADPKD should be considered as an indicator for long-term angiographic follow-up in patients with diagnosed IAs. © 2017 American Academy of Neurology.

Healing of Saccular Aneurysms Following Platinum Coil Embolization: Lack of Improved Efficacy with Vitamin C Supplementation

PubMed Central

Dai, Daying; Ding, Yong-Hong; Rezek, Issa; Lewis, Debra A.; Kallmes, David F.; Kadirvel, Ramanathan

2013-01-01

BACKGROUND AND PURPOSE To test the hypothesis that systemic administration of vitamin C, through its action of stimulating collagen synthesis and cross-linking, would decrease the recurrence and improve the occlusion experimental aneurysms treated with platinum coil embolization. METHODS Nineteen experimental aneurysms in female rabbits were embolized with platinum coils (>30% packing density). The animals were divided into three groups: Group 1 (n=6) rabbits served as controls, Group 2 (n=5) rabbits were fed with a vitamin C-supplemented feed and Group 3 (n=8) rabbits were medicated with vitamin C pills. Digital subtraction angiography was used to evaluate stability after embolization. Subjects were euthanized at 12 weeks after coil implantation, and serum vitamin C levels were then measured. Histological samples were examined with a grading system (range, 0-12) based on the neck and dome features. Masson Trichrome staining was employed to evaluate collagen deposition. Parametric data were analyzed with one-way analysis of variance and non-parametric data were examined using a Kruskal-Wallis test. RESULTS There were no significant differences between groups in mean aneurysm size. Mean serum vitamin C concentration was significantly higher in Group 3 and Group 2 compared to Group 1, while vitamin C levels between Group 2 and Group 3 were statistically comparable. Coil compaction was noted in one of six subjects in Group 1 and three of eight subjects in Group 3. All the remaining aneurysms in the test and control groups showed stable occlusion. There were no significant differences in histological scores or collagen deposition among groups. CONCLUSION Vitamin C supplementation following platinum coil embolization does not demonstrate improvement of long-term occlusion rates of aneurysms. PMID:22914744

Healing of saccular aneurysms following platinum coil embolization: lack of improved efficacy with vitamin C supplementation.

PubMed

Dai, Daying; Yong-Hong, Ding; Rezek, Issa; Lewis, Debra A; Kallmes, David F; Kadirvel, Ramanathan

2013-11-01

To test the hypothesis that systemic administration of vitamin C, through its action of stimulating collagen synthesis and crosslinking, would decrease the recurrence and improve the occlusion of experimental aneurysms treated with platinum coils. Experimental aneurysms were created in female rabbits and were embolized with platinum coils (>30% packing density). The animals were divided into three groups: group 1 (n=6) rabbits served as controls, group 2 (n=5) rabbits were fed with a vitamin C supplemented feed and group 3 (n=8) rabbits were medicated with vitamin C pills. Digital subtraction angiography was used to evaluate stability after embolization. Subjects were euthanized at 12 weeks after coil implantation, and serum vitamin C levels were then measured. Histological samples were examined with a grading system (range 0-12) based on the neck and dome features. Masson Trichrome staining was used to evaluate collagen deposition. Parametric data were analyzed with one way analysis of variance and non-parametric data were examined using a Kruskal-Wallis test. There were no significant differences between groups in mean aneurysm size. Mean serum vitamin C concentration was significantly higher in group 3 and group 2 compared with group 1, while vitamin C levels between group 2 and group 3 were statistically comparable. Coil compaction was noted in one of six subjects in group 1 and in three of eight subjects in group 3. All of the remaining aneurysms in the test and control groups showed stable occlusion. There were no significant differences in histological scores or collagen deposition among groups. Vitamin C supplementation following platinum coil embolization does not demonstrate improvement of long term occlusion rates of aneurysms.

Flow Diverter Stents for the Treatment of Anterior Cerebral Artery Aneurysms: Safety and Effectiveness.

PubMed

Clarençon, F; Di Maria, F; Gabrieli, J; Shotar, E; Zeghal, C; Nouet, A; Chiras, J; Sourour, N-A

2017-03-01

Flow diverter stents (FDSs) are increasingly used for the treatment of intracranial aneurysms. Initially developed for the management of giant and large aneurysms, their indications have progressively expanded. The purpose of our study was to evaluate the safety and effectiveness of FDSs for the treatment of anterior cerebral artery (ACA) aneurysms. Among the 94 consecutive patients treated for 100 intracranial aneurysms by means of FDSs in our institution from October 2010 to January 2015, eight aneurysms (8 %) in seven patients were located on the ACA. Three aneurysms were located on the A1 segment, three aneurysms on the anterior communicating artery (ACom) and two on the A2-A3 junction. In three cases, FDS was used for angiographic recurrence after coiling. Five patients were treated with a Pipeline embolization device, one with a NeuroEndograft and the last one with a Silk FDS. Treatment was feasible in all cases. No technical difficulty was reported. No acute or delayed clinical complication was recorded. Modified Rankin Scale was 0 for six patients and one for one patient. Mean angiographic follow-up was 9.7 ± 3.9 months (range 6-15). Total exclusion was observed in five aneurysms (71.4 %) and neck remnant in two (28.6 %) cases. One patient refused the control DSA. Our series shows the safety and effectiveness of FDSs for the treatment of ACA aneurysms.

The long-term outcomes of partial arch repair using the frozen elephant trunk technique for distal arch aortic aneurysm.

PubMed

Sueda, Taijiro; Takahashi, Shinya; Katayama, Keijiro; Morita, Shohei; Watanabe, Masazumi; Kurosaki, Tatsuya

2018-06-22

The purpose of this study was to evaluate the long-term results of partial arch repair using the frozen elephant trunk (FET) technique for distal arch aortic aneurysm and to examine the late complications. Thirty-eight patients with true distal arch aortic aneurysms were repaired with FET introduced through an incision in the proximal arch aorta. Follow-up computed tomography was performed every 6 or 12 months in 36 surviving patients. The maximum dimension of the excluded aneurysmal space was measured to determine whether the aneurysmal space had decreased or disappeared. Late complications were also evaluated during the long-term follow-up. There was 1 hospital death (2.6%) and 1 (2.6%) case of paraplegia. There were 2 late sudden deaths (5.2%) thought to be due to aneurysm rupture and arrhythmia. Postoperative serial-computed tomography showed shrinkage of the excluded aneurysmal space in 33 of 36 patients. Late aneurysmal formation occurred in the anastomotic site in three patients. One patient underwent thoracic endovascular stent grafting 10 years after surgery, 1 patient had total arch replacement 9 years after surgery, and 1 died due to rupture. Frozen elephant trunk was found to be a useful alternative for treating true distal arch aortic aneurysm. However, we must be alert for late aneurysmal formation at the incision site.

Origin, growth, and rupture of saccular aneurysms: a review.

PubMed

Sekhar, L N; Heros, R C

1981-02-01

Pathological and hemodynamic concepts regarding the origin, growth, and rupture of intracranial saccular aneurysms are reviewed. Aneurysms form as a result of an interplay between hemodynamic factors, such as axial stream impingement and the water hammer effect, and structural weaknesses at apices of arterial bifurcations, such as congenital and acquired medial defects, funnel-shaped dilatations, and areas of thinning. Hypertension and time aid the formation of aneurysms. Unknown factors in women and in some families also play a role. Enlargement of aneurysms results from an interplay between mechanical factors, such as self-excitation and resonance, that produce structural fatigue and pathological processes of repair of the aneurysmal wall. Rupture of aneurysms is caused by the same hemodynamic factors that effect growth and is also influenced by extramural pressure. Pathologically, a major rupture may be preceded by fibrinous and leukocytic infiltration of the wall, bleb formation, and a minor hemorrhage. Such minor leaks can be followed by healing and growth. Aneurysms that escape major hemorrhage or heal successfully after a hemorrhage can grow to giant proportions, but remain susceptible to rupture despite their size, unless they become completely thrombosed. Intramural thrombosis may be stimulated by minor leaks and is dependent upon the physical characteristics of aneurysms. Experimental, angiographic, and clinical studies that pertain to the origin, growth, and rupture of aneurysms are also reviewed.

The Incremental Value of Magnetic Resonance Imaging for Identification of Apical Pouch in Patients with Apical Variant of Hypertrophic Cardiomyopathy.

PubMed

Vucicevic, Darko; Lester, Steven J; Appleton, Christopher P; Panse, Prasad M; Schleifer, John William; Wilansky, Susan

2016-04-01

The development of a left ventricular (LV) apical pouch in patients with apical hypertrophic cardiomyopathy (aHCM) has been thought to be the transition point that can become an apical aneurysm, which is linked to higher risk of adverse events. In our study, we sought to compare the ability of transthoracic echocardiography (echo) and cardiac magnetic resonance imaging (cMRI) to accurately identify the presence of an apical pouch or aneurysm in patients with aHCM. We retrospectively reviewed the charts of all consecutive patients that had features of aHCM on imaging. Data from cMRI and echo examinations were abstracted, and the ability of these diagnostic modalities to identify the presence of a LV apical pouch and aneurysm was analyzed. Of 31 patients with aHCM, 17 (54.8%) had an apical pouch and 2 were found to have apical aneurysm (6.5%) on cMRI. Echo with and without perflutren contrast was able to accurately identify both aneurysms, but only 47.1% (8/17) of apical pouches seen by cMRI. Two patients had apical thrombus that was identified by cMRI, but not by echo. Our findings indicate that cMRI is superior to echo in identifying apical pouches in patients with aHCM. Our results also suggest that in patients undergoing echo, the use of perflutren contrast for LV opacification increases the diagnostic yield. Further study is necessary to delineate whether earlier identification of an apical pouch will be of clinical benefit for patients with aHCM by altering clinical management and avoiding adverse cardiovascular events. © 2015, Wiley Periodicals, Inc.

High-flow bypass with radial artery graft followed by internal carotid artery ligation for large or giant aneurysms of cavernous or cervical portion: clinical results and cognitive performance.

PubMed

Ono, Hideaki; Inoue, Tomohiro; Tanishima, Takeo; Tamura, Akira; Saito, Isamu; Saito, Nobuhito

2018-04-01

High-flow bypass followed by ligation of the internal carotid artery (ICA) is an effective treatment, but the impact of abrupt occlusion of the ICA is unpredictable, especially on postoperative cognitive function. The present study evaluated the clinical results as well as cognitive performances after high-flow bypass using radial artery graft (RAG) with supportive superficial temporal artery (STA)-middle cerebral artery (MCA) bypass, followed by ICA ligation. Ten consecutive patients underwent high-flow bypass surgery for large or giant ICA aneurysms of cavernous or cervical portion. Demographics, clinical information, magnetic resonance (MR) imaging, computed tomography, digital subtraction angiography (DSA), intraoperative somatosensory evoked potentials, neuropsychological examinations including the Wechsler Adult Intelligence Scale-Third Edition and the Wechsler Memory Scale-Revised (WMS-R), and follow-up data were analyzed. The aneurysm was located on the cavernous segment in eight cases and cervical segment in two cases, and mean aneurysm size was 27.9 mm. Postoperative DSA demonstrated robust bypass flow from the external carotid artery to MCA via the RAG, and no anterograde flow into the aneurysm. No patient showed new symptoms after the operation. Follow-up clinical study and MR imaging were performed in nine patients and showed no additional ischemic lesion compared with preoperative imaging. Seven patients completed neuropsychological examinations before and after surgery. All postoperative scores except WMS-R composite memory score slightly improved. High-flow bypass followed by ICA ligation can achieve good clinical outcomes. Successful high-flow bypass using RAG with supportive STA-MCA bypass and ICA ligation does not adversely affect postoperative cognitive function.

Gene expression profile of blood cells for the prediction of delayed cerebral ischemia after intracranial aneurysm rupture: a pilot study in humans.

PubMed

Baumann, Antoine; Devaux, Yvan; Audibert, Gérard; Zhang, Lu; Bracard, Serge; Colnat-Coulbois, Sophie; Klein, Olivier; Zannad, Faiez; Charpentier, Claire; Longrois, Dan; Mertes, Paul-Michel

2013-01-01

Delayed cerebral ischemia (DCI) is a potentially devastating complication after intracranial aneurysm rupture and its mechanisms remain poorly elucidated. Early identification of the patients prone to developing DCI after rupture may represent a major breakthrough in its prevention and treatment. The single gene approach of DCI has demonstrated interest in humans. We hypothesized that whole genome expression profile of blood cells may be useful for better comprehension and prediction of aneurysmal DCI. Over a 35-month period, 218 patients with aneurysm rupture were included in this study. DCI was defined as the occurrence of a new delayed neurological deficit occurring within 2 weeks after aneurysm rupture with evidence of ischemia either on perfusion-diffusion MRI, CT angiography or CT perfusion imaging, or with cerebral angiography. DCI patients were matched against controls based on 4 out of 5 criteria (age, sex, Fisher grade, aneurysm location and smoking status). Genome-wide expression analysis of blood cells obtained at admission was performed by microarrays. Transcriptomic analysis was performed using long oligonucleotide microarrays representing 25,000 genes. Quantitative PCR: 1 µg of total RNA extracted was reverse-transcribed, and the resulting cDNA was diluted 10-fold before performing quantitative PCR. Microarray data were first analyzed by 'Significance Analysis of Microarrays' software which includes the Benjamini correction for multiple testing. In a second step, microarray data fold change was compared using a two-tailed, paired t test. Analysis of receiver-operating characteristic (ROC) curves and the area under the ROC curves were used for prediction analysis. Logistic regression models were used to investigate the additive value of multiple biomarkers. A total of 16 patients demonstrated DCI. Significance Analysis of Microarrays software failed to retrieve significant genes, most probably because of the heterogeneity of the patients included in the microarray experiments and the small size of the DCI population sample. Standard two-tailed paired t test and C-statistic revealed significant associations between gene expression and the occurrence of DCI: in particular, the expression of neuroregulin 1 was 1.6-fold upregulated in patients with DCI (p = 0.01) and predicted DCI with an area under the ROC curve of 0.96. Logistic regression analyses revealed a significant association between neuroregulin 1 and DCI (odds ratio 1.46, 95% confidence interval 1.02-2.09, p = 0.02). This pilot study suggests that blood cells may be a reservoir of prognostic biomarkers of DCI in patients with intracranial aneurysm rupture. Despite an evident lack of power, this study elicited neuroregulin 1, a vasoreactivity-, inflammation- and angiogenesis-related gene, as a possible candidate predictor of DCI. Larger cohort studies are needed but genome-wide microarray-based studies are promising research tools for the understanding of DCI after intracranial aneurysm rupture. © 2013 S. Karger AG, Basel.

[Aneurysm of the atrial septum diagnosed by trans-esophageal echocardiography].

PubMed

Juszczyk, Z; Attir, A; Kamińska, M

1991-01-01

We report an uncommon case of atrial septal aneurysm associated with mitral valve prolapse. A 28 year old woman was studied with transthoracic and transesophageal echocardiography (TEE). Transthoracic echocardiography suggested mitral valve prolapse. TEE with color mapping was performed. Atrial septal aneurysm and mitral valve prolapse was found. The study has shown that TEE can evaluate accurately some of the anatomic features of atrial septal aneurysm and color flow mapping can provide accurate information about the blood flow in the lesion. We believe that TEE may be the safest and most accurate investigative technique for diagnosing this rare lesion.

Exploring the age of intracranial aneurysms using carbon birth dating: preliminary results.

PubMed

Etminan, Nima; Dreier, Rita; Buchholz, Bruce A; Bruckner, Peter; Steiger, Hans-Jakob; Hänggi, Daniel; Macdonald, R Loch

2013-03-01

There is a controversy about the time span over which cerebral aneurysms develop. In particular, it is unknown whether collagen in ruptured aneurysms undergoes more rapid turnover than in unruptured aneurysms.(14)C birth dating of collagen could be used to address this question. Aneurysmal domes from patients undergoing surgical treatment for ruptured or unruptured aneurysms were excised. Aneurysmal collagen was isolated and purified after pepsin digestion. Collagen from mouse tendons served as controls. F(14)C levels in collagen were analyzed by accelerator mass spectrometry and correlated with patient age and aneurysm size. Analysis of 10 aneurysms from 9 patients (6 ruptured, 3 unruptured) revealed an average aneurysm collagen age of <5 years, generally irrespective of patient age and aneurysm size or rupture status. Interestingly, F(14)C levels correlated with patient age as well as aneurysm size in ruptured aneurysm collagen samples. Our preliminary data suggest that collagen extracted from intracranial aneurysms generally has a high turnover, associated with aneurysm size and patient age. The correlation of patient age and aneurysm F(14)C levels could explain models of aneurysm development. Although preliminary, our findings may have implications for the biological and structural stability of ruptured and unruptured intracranial aneurysms.

Role of 0D peripheral vasculature model in fluid-structure interaction modeling of aneurysms

NASA Astrophysics Data System (ADS)

Torii, Ryo; Oshima, Marie; Kobayashi, Toshio; Takagi, Kiyoshi; Tezduyar, Tayfun E.

2010-06-01

Patient-specific simulations based on medical images such as CT and MRI offer information on the hemodynamic and wall tissue stress in patient-specific aneurysm configurations. These are considered important in predicting the rupture risk for individual aneurysms but are not possible to measure directly. In this paper, fluid-structure interaction (FSI) analyses of a cerebral aneurysm at the middle cerebral artery (MCA) bifurcation are presented. A 0D structural recursive tree model of the peripheral vasculature is incorporated and its impedance is coupled with the 3D FSI model to compute the outflow through the two branches accurately. The results are compared with FSI simulation with prescribed pressure variation at the outlets. The comparison shows that the pressure at the two outlets are nearly identical even with the peripheral vasculature model and the flow division to the two branches is nearly the same as what we see in the simulation without the peripheral vasculature model. This suggests that the role of the peripheral vasculature in FSI modeling of the MCA aneurysm is not significant.

Hemodynamic Changes Caused by Flow Diverters in Rabbit Aneurysm Models: Comparison of Virtual and Realistic FD Deployments Based on Micro-CT Reconstruction

PubMed Central

Fang, Yibin; Yu, Ying; Cheng, Jiyong; Wang, Shengzhang; Wang, Kuizhong; Liu, Jian-Min; Huang, Qinghai

2013-01-01

Adjusting hemodynamics via flow diverter (FD) implantation is emerging as a novel method of treating cerebral aneurysms. However, most previous FD-related hemodynamic studies were based on virtual FD deployment, which may produce different hemodynamic outcomes than realistic (in vivo) FD deployment. We compared hemodynamics between virtual FD and realistic FD deployments in rabbit aneurysm models using computational fluid dynamics (CFD) simulations. FDs were implanted for aneurysms in 14 rabbits. Vascular models based on rabbit-specific angiograms were reconstructed for CFD studies. Real FD configurations were reconstructed based on micro-CT scans after sacrifice, while virtual FD configurations were constructed with SolidWorks software. Hemodynamic parameters before and after FD deployment were analyzed. According to the metal coverage (MC) of implanted FDs calculated based on micro-CT reconstruction, 14 rabbits were divided into two groups (A, MC >35%; B, MC <35%). Normalized mean wall shear stress (WSS), relative residence time (RRT), inflow velocity, and inflow volume in Group A were significantly different (P<0.05) from virtual FD deployment, but pressure was not (P>0.05). The normalized mean WSS in Group A after realistic FD implantation was significantly lower than that of Group B. All parameters in Group B exhibited no significant difference between realistic and virtual FDs. This study confirmed MC-correlated differences in hemodynamic parameters between realistic and virtual FD deployment. PMID:23823503

Predictors of residual flow in embolized intracranial ruptured aneurysms at early follow-up.

PubMed

Serafin, Zbigniew; Strześniewski, Piotr; Beuth, Wojciech

2014-01-01

The possibility of recanalization and the need for retreatment are the most important drawbacks of intracranial aneurysm embolization. The purpose of the study was to prospectively analyze the results of early follow-up angiography of embolized ruptured aneurysms in an attempt to determine factors predicting the presence of residual flow. Evaluation included 72 patients with 72 aneurysms, which were followed-up 3 months after the treatment. Analysis of residual flow predictors included: age and gender, clinical state in Hunt-Hess scale, aneurysm localization, aneurysm three dimensions and volume, neck width, sac-to-neck ratio, initial result of embolization, number of coils used and the use of hydrogel coils and stents. Mean sac diameter was 6.5±3.9 mm, and mean neck width was 2.9±1.4 mm. Follow-up angiography presented residual flow in 26 aneurysms (36.1%): class 2 in 8 aneurysms (11.1%), and class 3 in 18 cases (25.0%). Stable aneurysm filling was observed in 45 cases (62.5%), progression of residual flow in 25 cases (34.7%), and regression in 2 cases (2.8%). According to ROC analysis independent predictors of residual flow were aneurysm neck diameter (AUC 0.857, 95% CI: 0.755-0.928, p<0.0001) and sac-to-neck ratio (AUC 0.817, 95% CI: 0.708-0.898, p<0.0001). Cut-off point of the ROC curve was established at 2.8 mm for neck diameter, and 1.73 for sac-to-neck ratio. Aneurysm neck diameter and sac-to-neck ratio are independently related to the residual flow in embolized ruptured aneurysms at early follow-up.

Changing Paradigms in the Endovascular Management of Ruptured Anterior Communicating Artery Aneurysms.

PubMed

Moon, Karam; Park, Min S; Albuquerque, Felipe C; Levitt, Michael R; Mulholland, Celene B; McDougall, Cameron G

2017-10-01

Approximately 17% of ruptured anterior communicating artery (ACoA) aneurysms were deemed unsuitable for coil embolization during the Barrow Ruptured Aneurysm Trial (BRAT), most commonly due to unfavorable dome-to-neck ratio or small size. To compare patients treated by coil embolization for ruptured ACoA aneurysms during the trial to those treated after the trial to determine whether advances in endovascular techniques have allowed for effective treatment of these lesions. All cases of ruptured ACoA aneurysms treated by endovascular modalities during BRAT (2003-2007) and post-BRAT (2007-2012) were reviewed for patient and aneurysm characteristics, treatment types, and clinical and angiographic outcomes at 3-yr or last follow-up. The BRAT ACoA cohort included 39 patients treated with coiling (excluding those crossed over to clipping). The post-BRAT cohort included 93 patients who were significantly older (mean age, 59.5 vs 52.8 yr, P = .005) than the BRAT cohort; there were no significant cohort differences in sex, Hunt and Hess grade, or mean aneurysm size. The use of balloon remodeling was significantly higher in the post-BRAT cohort (31.2% [29/93] vs 5.1% [2/39], P = .001), as was the proportion of wide-necked aneurysms treated (66.7% [62/93] vs 30.8% [12/39], P < .001). There was no significant difference in clinical outcome or retreatment rate between the 2 cohorts (P = .90 and P = .48, respectively). ACoA lesions thought unamenable to endovascular therapy in an earlier randomized trial are now successfully coiled with increased use of adjunctive techniques, without sacrificing patient outcome or treatment durability. Copyright © 2016 by the Congress of Neurological Surgeons.

Visceral Artery Aneurysms in Liver Transplant Candidates and in Patients after Liver Transplantation

PubMed Central

Maggi, Umberto; Dondossola, Daniele; Consonni, Dario; Gatti, Stefano; Arnoldi, Rossella; Bossi, Manuela; Rossi, Giorgio

2011-01-01

There are only few reviews concerning visceral aneurysms in cirrhotics, and a small number of papers on visceral aneurysms in liver transplant patients. The present paper investigates this condition in both groups of patients in a 10-year-retrospective study. PMID:22216310

Greater rupture risk for familial as compared to sporadic unruptured intracranial aneurysms.

PubMed

Broderick, Joseph P; Brown, Robert D; Sauerbeck, Laura; Hornung, Richard; Huston, John; Woo, Daniel; Anderson, Craig; Rouleau, Guy; Kleindorfer, Dawn; Flaherty, Matthew L; Meissner, Irene; Foroud, Tatiana; Moomaw, E Charles J; Connolly, E Sander

2009-06-01

The risk of intracranial aneurysm (IA) rupture in asymptomatic members of families who have multiple affected individuals is not known. First-degree unaffected relatives of those with a familial history of IA who had a history of smoking or hypertension but no known IA were offered cerebral MR angiography (MRA) and followed yearly as part of a National Institute of Neurological Diseases and Stroke-funded study of familial IA (Familial Intracranial Aneurysm [FIA] Study). A total of 2874 subjects from 542 FIA Study families were enrolled. After study enrollment, MRAs were performed in 548 FIA Study family members with no known history of IA. Of these 548 subjects, 113 subjects (20.6%) had 148 IAs by MRA of whom 5 subjects had IA >or=7 mm. Two subjects with an unruptured IA by MRA/CT angiography (3-mm and 4-mm anterior communicating artery) subsequently had rupture of their IA. This represents an annual rate of 1.2 ruptures per 100 subjects (1.2% per year; 95% CI, 0.14% to 4.3% per year). None of the 435 subjects with a negative MRA have had a ruptured IA. Survival curves between the MRA-positive and -negative cohorts were significantly different (P=0.004). This rupture rate of unruptured IA in the FIA Study cohort of 1.2% per year is approximately 17 times higher than the rupture rate for subjects with an unruptured IA in the International Study of Unruptured Aneurysm Study with a matched distribution of IA size and location 0.069% per year. Small unruptured IAs in patients from FIA Study families may have a higher risk of rupture than sporadic unruptured IAs of similar size, which should be considered in the management of these patients.

Use of regional mechanical properties of abdominal aortic aneurysms to advance finite element modeling of rupture risk.

PubMed

Tierney, Áine P; Callanan, Anthony; McGloughlin, Timothy M

2012-02-01

To investigate the use of regional variations in the mechanical properties of abdominal aortic aneurysms (AAA) in finite element (FE) modeling of AAA rupture risk, which has heretofore assumed homogeneous mechanical tissue properties. Electrocardiogram-gated computed tomography scans from 3 male patients with known infrarenal AAA were used to characterize the behavior of the aneurysm in 4 different segments (posterior, anterior, and left and right lateral) at maximum diameter and above the infrarenal aorta. The elasticity of the aneurysm (circumferential cyclic strain, compliance, and the Hudetz incremental modulus) was calculated for each segment and the aneurysm as a whole. The FE analysis inclusive of prestress (pre-existing tensile stress) produced a detailed stress pattern on each of the aneurysm models under pressure loading. The 4 largest areas of stress in each region were considered in conjunction with the local regional properties of the segment to define a specific regional prestress rupture index (RPRI). In terms of elasticity, there were average reductions of 68% in circumferential cyclic strain and 63% in compliance, with a >5-fold increase in incremental modulus, between the healthy and the aneurysmal aorta for each patient. There were also regional variations in all elastic properties in each individual patient. The average difference in total stress inclusive of prestress was 59%, 67%, and 15%, respectively, for the 3 patients. Comparing the strain from FE models with the CT scans revealed an average difference in strain of 1.55% for the segmented models and 3.61% for the homogeneous models, which suggests that the segmented models more accurately reflect in vivo behavior. RPRI values were calculated for each segment for all patients. A greater understanding of the local material properties and their use in FE models is essential for greater accuracy in rupture prediction. Quantifying the regional behavior will yield insight into the changes in patient-specific aneurysms and increase understanding about the progression of aneurysmal disease.

Comparison of Intraoperative Indocyanine Green Angiography and Digital Subtraction Angiography for Clipping of Intracranial Aneurysms

PubMed Central

Doss, Vinodh T.; Goyal, Nitin; Humphries, William; Hoit, Dan; Arthur, Adam; Elijovich, Lucas

2015-01-01

Background Residual aneurysm after microsurgical clipping carries a risk of aneurysm growth and rupture. Digital subtraction angiography (DSA) remains the standard to determine the adequacy of clipping. Intraoperative indocyanine green (ICG) angiography is increasingly utilized to confirm optimal clip positioning across the neck and to evaluate the adjacent vasculature. Objective We evaluated the correlation between ICG and DSA in clipped intracranial aneurysms. Methods A retrospective study of patients who underwent craniotomy and microsurgical clipping of intracranial aneurysms with ICG for 2 years. Patient characteristics, presentation details, operative reports, and pre- and postclipping angiographic images were reviewed to determine the adequacy of the clipping. Results Forty-seven patients underwent clipping with ICG and postoperative DSA: 57 aneurysms were clipped; 23 patients (48.9%) presented with subarachnoid hemorrhage. Nine aneurysms demonstrated a residual on DSA not identified on ICG (residual sizes ranged from 0.5 to 4.3 mm; average size: 1.8 mm). Postoperative DSA demonstrated no branch occlusions. Conclusion Intraoperative ICG is useful in the clipping of intracranial aneurysms to ensure a gross patency of branch vessels; however, the presence of residual aneurysms and subtle changes in flow in branch vessels is best seen by DSA. This has important clinical implications with regard to follow-up imaging and surgical/endovascular management. PMID:26279659

Continuous infusion of low-dose unfractionated heparin after aneurysmal subarachnoid hemorrhage: a preliminary study of cognitive outcomes.

PubMed

James, Robert F; Khattar, Nicolas K; Aljuboori, Zaid S; Page, Paul S; Shao, Elaine Y; Carter, Lacey M; Meyer, Kimberly S; Daniels, Michael W; Craycroft, John; Gaughen, John R; Chaudry, M Imran; Rai, Shesh N; Everhart, D Erik; Simard, J Marc

2018-05-11

OBJECTIVE Cognitive dysfunction occurs in up to 70% of aneurysmal subarachnoid hemorrhage (aSAH) survivors. Low-dose intravenous heparin (LDIVH) infusion using the Maryland protocol was recently shown to reduce clinical vasospasm and vasospasm-related infarction. In this study, the Montreal Cognitive Assessment (MoCA) was used to evaluate cognitive changes in aSAH patients treated with the Maryland LDIVH protocol compared with controls. METHODS A retrospective analysis of all patients treated for aSAH between July 2009 and April 2014 was conducted. Beginning in 2012, aSAH patients were treated with LDIVH in the postprocedural period. The MoCA was administered to all aSAH survivors prospectively during routine follow-up visits, at least 3 months after aSAH, by trained staff blinded to treatment status. Mean MoCA scores were compared between groups, and regression analyses were performed for relevant factors. RESULTS No significant differences in baseline characteristics were observed between groups. The mean MoCA score for the LDIVH group (n = 25) was 26.4 compared with 22.7 in controls (n = 22) (p = 0.013). Serious cognitive impairment (MoCA ≤ 20) was observed in 32% of controls compared with 0% in the LDIVH group (p = 0.008). Linear regression analysis demonstrated that only LDIVH was associated with a positive influence on MoCA scores (β = 3.68, p =0.019), whereas anterior communicating artery aneurysms and fevers were negatively associated with MoCA scores. Multivariable linear regression analysis resulted in all 3 factors maintaining significance. There were no treatment complications. CONCLUSIONS This preliminary study suggests that the Maryland LDIVH protocol may improve cognitive outcomes in aSAH patients. A randomized controlled trial is needed to determine the safety and potential benefit of unfractionated heparin in aSAH patients.

Fluid Structure Interaction Analysis on Sidewall Aneurysm Models

NASA Astrophysics Data System (ADS)

Hao, Qing

2016-11-01

Wall shear stress is considered as an important factor for cerebral aneurysm growth and rupture. The objective of present study is to evaluate wall shear stress in aneurysm sac and neck by a fluid-structure-interaction (FSI) model, which was developed and validated against the particle image velocimetry (PIV) data. In this FSI model, the flow characteristics in a straight tube with different asymmetric aneurysm sizes over a range of Reynolds numbers from 200 to 1600 were investigated. The FSI results agreed well with PIV data. It was found that at steady flow conditions, when Reynolds number above 700, one large recirculating vortex would be formed, occupying the entire aneurysm sac. The center of the vortex is located at region near to the distal neck. A pair of counter rotating vortices would however be formed at Reynolds number below 700. Wall shear stresses reached highest level at the distal neck of the aneurysmal sac. The vortex strength, in general, is stronger at higher Reynolds number. Fluid Structure Interaction Analysis on Sidewall Aneurysm Models.

Effect of hemodynamics on outcome of subtotally occluded paraclinoid aneurysms after stent-assisted coil embolization.

PubMed

Liu, Jian; Jing, Linkai; Wang, Chao; Paliwal, Nikhil; Wang, Shengzhang; Zhang, Ying; Xiang, Jianping; Siddiqui, Adnan H; Meng, Hui; Yang, Xinjian

2016-11-01

Endovascular treatment of paraclinoid aneurysms is preferred in clinical practice. Flow alterations caused by stents and coils may affect treatment outcome. To assess hemodynamic changes following stent-assisted coil embolization (SACE) in subtotally embolized paraclinoid aneurysms with residual necks that were predisposed to recanalization. We studied 27 paraclinoid aneurysms (seven recanalized and 20 stable) treated with coils and Enterprise stents. Computational fluid dynamic simulations were performed on patient-specific aneurysm geometries using virtual stenting and porous media technology. After stent placement in 27 cases, aneurysm flow velocity decreased significantly, the reduction gradually increasing from the neck plane (11.9%), to the residual neck (12.3%), to the aneurysm dome (16.3%). Subsequent coil embolization was performed after stent placement and the hemodynamic factors decreased further and significantly at all aneurysm regions except the neck plane. In a comparison of recanalized and stable cases, univariate analysis showed no significant differences in any parameter before treatment. After stent-assisted coiling, only the reduction in area-averaged velocity at the neck plane differed significantly between recanalized (8.1%) and stable cases (20.5%) (p=0.016). Aneurysm flow velocity can be significantly decreased by stent placement and coil embolization. However, hemodynamics at the aneurysm neck plane is less sensitive to coils. Significant reduction in flow velocity at the neck plane may be an important factor in preventing recanalization of paraclinoid aneurysms after subtotal SACE. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Association Between Vascular Anatomy and Posterior Communicating Artery Aneurysms.

PubMed

Can, Anil; Ho, Allen L; Emmer, Bart J; Dammers, Ruben; Dirven, Clemens M F; Du, Rose

2015-11-01

Hemodynamic stress, conditioned by the geometry and morphology of the vessel trees, plays an important role in the formation of intracranial aneurysms. The aim of this study was to identify image-based location-specific morphologic parameters that are associated with posterior communicating artery (PCoA) aneurysms. Morphologic parameters obtained from computed tomography angiography of 56 patients with PCoA aneurysms and 23 control patients were evaluated with 3D Slicer, an open-source image analysis software, to generate 3-dimensional models of the aneurysms and surrounding vasculature. Segment lengths, diameters, and vessel-to-vessel angles were examined. To control for genetic and clinical risk factors, the unaffected contralateral side of patients with unilateral PCoA aneurysms was used as a control group for internal carotid artery (ICA)-related parameters. A separate control group with visible PCoAs and aneurysms elsewhere was used as a control group for PCoA-related parameters. Internal carotid artery-related parameters were not statistically different between the PCoA aneurysm and control groups. Univariate and multivariate subgroup analysis for patients with visualized PCoAs demonstrated that a larger PCoA diameter was significantly associated with the presence of a PCoA aneurysm (odds ratio = 12.1, 95% confidence interval = 1.3-17.1, P = 0.04) after adjusting for other morphologic parameters. Larger PCoA diameters are associated with the presence of PCoA aneurysms. These parameters may provide objective metrics to assess aneurysm formation and growth risk stratification in high-risk patients. Copyright © 2015 Elsevier Inc. All rights reserved.

A Matched Case-Control Study on Open and Endovascular Treatment of Popliteal Artery Aneurysms.

PubMed

Dorigo, W; Fargion, A; Masciello, F; Piffaretti, G; Pratesi, G; Giacomelli, E; Pratesi, C

2018-01-01

To compare early and late results of open and endovascular management of popliteal artery aneurysm in a retrospective single-center matched case-control study Methods: From 1981 to 2015, 309 consecutive interventions for popliteal artery aneurysm were performed in our institution, in 59 cases with endovascular repair and in 250 cases with open repair. Endovascular repair was preferred in older asymptomatic patients, while open repair was offered more frequently to patients with a thrombosed popliteal artery aneurysm and a poor run-off status. A one-to-one coarsened exact matching on the basis of the baseline demographic, clinical, and anatomical covariates significantly different between the two treatment options was performed and two equivalent groups of 56 endovascular repairs and open repairs were generated. The two groups were compared in terms of perioperative results with χ 2 test and of follow-up outcomes with the Kaplan-Meier curves and log-rank test. There were no differences between the two groups in terms of perioperative outcomes. Median duration of follow-up was 38 months. Five-year survival rates were 94% in endovascular repair group and 89.5% in open repair group (p = 0.4, log-rank 0.6). Primary patency rates at 1, 3, and 5 years were 81%, 78%, and 72% in endovascular repair group and 82.5%, 80%, and 64% in open repair group (p = 0.8, log-rank 0.01). Freedom from reintervention at 5 years was 65.5% in endovascular repair group and 76% in open repair group (p = 0.2, log-rank 1.2). Secondary patency at 1, 3, and 5 years was 94%, 86%, and 74% in endovascular repair group, and 94%, 89%, and 71% in open repair group, respectively (p = 0.9, log-rank 0.01). The rates of limb preservation at 5 years were 94% in endovascular repair group and 86.4% in open repair group (p = 0.3, log-rank 0.8). Open repair and endovascular repair of popliteal artery aneurysms provided in this retrospective single-center experience similar perioperative and follow-up results in equivalent groups of patients.

Evaluation of flow with dynamic x-ray imaging for aneurysms

NASA Astrophysics Data System (ADS)

Dohatcu, Andreea Cristina

The main goal of this thesis is to evaluate blood flow inside cerebrovascular aneurysms using dynamic x-ray imaging. X-ray contrast substance (dye) was auto injected in elastomer aneurysm models placed in a flow loop (for in-vitro studies) to trace flow passing through aneurysms. More specifically, an improved Time-Density Curves (TDC) Roentgen-videodensitometric tracking technique, that included looking to designated regions (R) within an aneurysm rather than focusing on the entire aneurysm, was employed to get information about blood flow using cine-angiographic sequences. It is the first time R-TDC technique has been used. In complex real-time interventions on patients, 2D/3D angiographic analysis of contrast media flow is the only reliable and rapid source of information that we have in order to assess the seriousness of the disease, suggest the treatment, and verify the result of the treatment. The present study focused on finding a "correlation metric" to quantitatively describe the flow behavior within the aneurysms and examine the hemodynamic implications of several treatments using flow modulating devices applied to saccular and bifurcation geometries aneurysms. The main idea in treatment of an aneurysm is rapid reduction of the risk of rupture. This is usually done endovascularly now by totally occluding the aneurysm by packing it with mechanical or chemical agents. Our research, however, involves a new method of blocking the neck using various types of asymmetric vascular stents (AVS). We proposed and analyzed, using R-TDCs, the feasibility of a new modified endovascular method of treatment based on alteration of blood flow through the aneurysm by partial occlusion only. In-vitro studies using aneurysm phantoms with patient-specific aneurysm models were performed. Also, for the first time the new methods were used in in-vivo studies as well, on rabbit-model experimental data, in an attempt to correlate thrombogenic response of a living organism to flow characteristics as a result of interaction with an AVS. A comparison with optical-dye-dilution data and 3D Computational Fluid Dynamics virtual angiography (CFD) data in similar conditions was also performed. Task oriented optimization of x-ray system parameters with regard to the needs of obtaining TDCs so as to obtain more accurate information of contrast media flow into aneurysms from angiographic images, were done. This includes a comparison between a commercial x-ray Flat Panel Detector (FPD) and an in-house new x-ray micro detector prototype, the Micro-Angiographic Fluoroscope (MAF). X-ray dose levels given in clinical procedures similar in length and complexity to aneurysm treatments, were studied on a statistical representative batch. It was concluded that there is a need for reduction of radiation-induced skin injuries to patients following interventional procedures. Hence, we developed and assessed a method to evaluate the variation of image quality (which impacts the success of TDC analysis) and dose with the acquisition mode operation logic and the automatic-brightness-control (ABC); this method was applied to two clinical interventional fluoroscopic imaging systems: one with an Image Intensifier (II) and the other with a Flat Panel Detector (FPD). The resultant ABC tracking curves obtained for the various imaging modes available on a given system can then be used for proper selection of technique to achieve the needed contrast signal to noise ratio to acquire adequate data for TDC evaluation, while controlling the patient dose.

Endovascular treatment of a true posterior communicating artery aneurysm.

PubMed

Munarriz, Pablo M; Castaño-Leon, Ana M; Cepeda, Santiago; Campollo, Jorge; Alén, Jose F; Lagares, Alfonso

2014-01-01

Posterior communicating artery (PCoA) aneurysms are most commonly located at the junction of the internal carotid artery and the PCoA. "True" PCoA aneurysms, which originate from the PCoA itself, are rarely encountered. Most previously reported cases were treated surgically mainly before the endovascular option became available. A 53-year-old male presented with sudden onset of right hemiparesis and aphasia. Left middle cerebral artery stroke was diagnosed. Further studies revealed a 3 mm left PCoA aneurysm arising from the PCoA itself, attached to neither the internal carotid artery nor the posterior cerebral artery. Endovascular treatment was performed and the aneurysm was coiled completely. Technical advances in endovascular interventional technology have permitted an additional approach to these lesions. The possible endovascular significance of the treatment of true PCoA aneurysms is discussed.

[An aortic and femoral aneurysm revealing Behçet's disease].

PubMed

Lyazidi, Y; Abissegue, Y; Chtata, H T; Taberkant, M

2015-12-01

Vascular involvement in Behçet's disease is rare, but may be inaugural in many cases. We report a case of Behçet's disease revealed by two pre-rupture aneurysms - a subrenal abdominal aortic aneurysm and a femoral aneurysm. This patient had only one of the International Study Group for Behçet's disease diagnostic criteria: pseudofolliculitis. Behçet's disease must be considered as a possible diagnosis in patients with unexplained inflammatory arteriopathy. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

The pathogenesis shared between abdominal aortic aneurysms and intracranial aneurysms: a microarray analysis.

PubMed

Wang, Wen; Li, Hao; Zhao, Zheng; Wang, Haoyuan; Zhang, Dong; Zhang, Yan; Lan, Qing; Wang, Jiangfei; Cao, Yong; Zhao, Jizong

2018-04-01

Abdominal aortic aneurysms (AAAs) and intracranial saccular aneurysms (IAs) are the most common types of aneurysms. This study was to investigate the common pathogenesis shared between these two kinds of aneurysms. We collected 12 IAs samples and 12 control arteries from the Beijing Tiantan Hospital and performed microarray analysis. In addition, we utilized the microarray datasets of IAs and AAAs from the Gene Expression Omnibus (GEO), in combination with our microarray results, to generate messenger RNA expression profiles for both AAAs and IAs in our study. Functional exploration and protein-protein interaction (PPI) analysis were performed. A total of 727 common genes were differentially expressed (404 was upregulated; 323 was downregulated) for both AAAs and IAs. The GO and pathway analyses showed that the common dysregulated genes were mainly enriched in vascular smooth muscle contraction, muscle contraction, immune response, defense response, cell activation, IL-6 signaling and chemokine signaling pathways, etc. The further protein-protein analysis identified 35 hub nodes, including TNF, IL6, MAPK13, and CCL5. These hub node genes were enriched in inflammatory response, positive regulation of IL-6 production, chemokine signaling pathway, and T/B cell receptor signaling pathway. Our study will gain new insight into the molecular mechanisms for the pathogenesis of both types of aneurysms and provide new therapeutic targets for the patients harboring AAAs and IAs.

Flow in cerebral aneurysms: 4D Flow MRI measurements and CFD models

NASA Astrophysics Data System (ADS)

Rayz, Vitaliy; Schnell, Susanne

2017-11-01

4D Flow MRI is capable of measuring blood flow in vivo, providing time-resolved velocity fields in 3D. The dynamic range of the 4D Flow MRI is determined by a velocity sensitivity parameter (venc), set above the expected maximum velocity, which can result in noisy data for slow flow regions. A dual-venc 4D flow MRI technique, where both low- and high-venc data are acquired, can improve velocity-to-noise ratio and, therefore, quantification of clinically-relevant hemodynamic metrics. In this study, patient-specific CFD simulations were used to evaluate the advantages of the dual-venc approach for assessment of the flow in cerebral aneurysms. The flow in 2 cerebral aneurysms was measured in vivo with dual-venc 4D Flow MRI and simulated with CFD, using the MRI data to prescribe flow boundary conditions. The flow fields obtained with computations were compared to those measured with a single- and dual-venc 4D Flow MRI. The numerical models resolved small flow structures near the aneurysmal wall, that were not detected with a single-venc acquisition. Comparison of the numerical and imaging results shows that the dual-venc approach can improve the accuracy of the 4D Flow MRI measurements in regions characterized by high-velocity jets and slow recirculating flows.

Endovascular Treatment of Cerebral Aneurysm with Coils and Onyx

PubMed Central

Ueno, J.; Tohma, N.

2004-01-01

Summary We investigated endovascular treatment of cerebral aneurysm by coil and Onyx in vivo experiment in order to promote the advantages of coil embolization,. The aim of this study was to clarify the advantages and problems of coil and Onyx embolization and to evaluate its potentials for application in clinical medicine. We set experimental aneurysms made of external jugular vein to bilateral carotid arteries of 10 Beagle dogs and embolized aneurysm with coils and Onyx. Two months later, the dogs were sacrificed and took out the experimental aneurysms and examined them histologically. We have experienced Onyx migration into the vessel at the beginning of our experiment. Technical problems were as follows; Onyx was not easily visible on DSA monitor particularly in tight coil packing. Catheter tip was often stuck to the Onyx in the aneurysm. Protect balloon could not completely protect the Onyx leakage into the vessel. Microscopic examinations were as follows; The aneurysm was filled with Onyx, coils, and inflammatory reactants. The orifice of the aneurysm was packed with augmented fibrous tissue. 1. This method increased contact between the aneurysm wall and coils. 2. Onyx filled the intra-aneurismal space more tightly. 3. Coils prevented Onyx from flowing out into the vessel. 4. In Onyx, intimal layer was more rapidly formed at the neck of the aneurysm than coils only. 5. The most important problems during Onyx embolization is how to prevent Onyx migration into the vessel. We should like to propose the guideline for Onyx embolization. PMID:20587272

Endovascular Treatments in Combination with Extracranial-Intracranial Bypass for Complex Intracranial Aneurysms.

PubMed

Sato, Kenichi; Endo, Hidenori; Fujimura, Miki; Endo, Toshiki; Matsumoto, Yasushi; Shimizu, Hiroaki; Tominaga, Teiji

2018-05-01

Although most intracranial aneurysms can be treated with microsurgery or endovascular procedure alone, a subset of aneurysms may require a combined approach. The purpose of this study was to assess the efficacy of endovascular interventions combined with bypass surgery for the treatment of complex intracranial aneurysms. We retrospectively reviewed medical records from a prospectively maintained patient database to identify patients who underwent endovascular treatment of an intracranial aneurysm at our institutes between 2007 and 2017. We recruited patients who received a preplanned combination of endovascular treatment and extracranial-intracranial bypass surgery. Forty-four patients (44 aneurysms) were treated with a combined approach. Twenty-four patients presented with subarachnoid hemorrhage. Treatment strategies included endovascular parent artery occlusion with the bypass surgery to restore cerebral blood flow (n = 12), endovascular trapping with bypass surgery to isolate incorporated branches (n = 12), and intra-aneurysmal coil embolization with bypass surgery to isolate incorporated branches (n = 20). During a mean period of 35.6 months, follow-up catheter angiography was performed in 35 of 44 patients (79.5%) and demonstrated complete aneurysm obliteration in 29 patients (82.9%) and bypass patency in 33 (94.3%). The postoperative aneurysm-related mortality and morbidity rates were 6.8% and 13.6%, respectively. Combined endovascular and surgical bypass procedures are useful for the treatment of complex intracranial aneurysms when conventional surgical or endovascular techniques are not feasible and show acceptable rates of morbidity and mortality. Copyright © 2018 Elsevier Inc. All rights reserved.

Description of human AAA by cytokine and immune cell aberrations compared to risk-factor matched controls.

PubMed

Wang, S Keisin; Green, Linden A; Gutwein, Ashley R; Drucker, Natalie A; Motaganahalli, Raghu L; Gupta, Alok K; Fajardo, Andres; Murphy, Michael P

2018-04-28

The pathogenesis driving the formation of abdominal aortic aneurysms continues to be poorly understood. Therefore, we systemically define the cytokine and circulating immune cell environment observed in human abdominal aortic aneurysm compared with risk-factor matched controls. From 2015 to 2017, a total of 274 patients donated blood to the Indiana University Center for Aortic Disease. Absolute concentrations of circulating cytokines were determined, using enzyme-linked immunosorbent assays while the expression of circulating immune cell phenotypes were assayed via flow cytometric analysis. Human abdominal aortic aneurysm is characterized by a significant depletion of the antigen-specific, CD4 + Tr1 regulatory lymphocyte that corresponds to an upregulation of the antigen-specific, inflammatory Th17 cell. We found no differences in the incidence of Treg, B10, and myeloid-derived suppressor regulatory cells. Similarly, no disparities were noted in the following inflammatory cytokines: IL-1β, C-reactive protein, tumor necrosis factor α, interferon γ, and IL-23. However, significant upregulation of the inflammatory cytokines osteopontin, IL-6, and IL-17 were noted. Additionally, no changes were observed in the regulatory cytokines IL-2, IL-4, IL-13, TNF-stimulated gene 6 protein, and prostaglandin E2, but we did observe a significant decrease in the essential regulatory cytokine IL-10. In this investigation, we systematically characterize the abdominal aortic aneurysm-immune environment and present preliminary evidence that faulty immune regulation may also contribute to aneurysm formation and growth. Copyright © 2018 Elsevier Inc. All rights reserved.

Augmented reality in the surgery of cerebral aneurysms: a technical report.

PubMed

Cabrilo, Ivan; Bijlenga, Philippe; Schaller, Karl

2014-06-01

Augmented reality is the overlay of computer-generated images on real-world structures. It has previously been used for image guidance during surgical procedures, but it has never been used in the surgery of cerebral aneurysms. To report our experience of cerebral aneurysm surgery aided by augmented reality. Twenty-eight patients with 39 unruptured aneurysms were operated on in a prospective manner with augmented reality. Preoperative 3-dimensional image data sets (angio-magnetic resonance imaging, angio-computed tomography, and 3-dimensional digital subtraction angiography) were used to create virtual segmentations of patients' vessels, aneurysms, aneurysm necks, skulls, and heads. These images were injected intraoperatively into the eyepiece of the operating microscope. An example case of an unruptured posterior communicating artery aneurysm clipping is illustrated in a video. The described operating procedure allowed continuous monitoring of the accuracy of patient registration with neuronavigation data and assisted in the performance of tailored surgical approaches and optimal clipping with minimized exposition. Augmented reality may add to the performance of a minimally invasive approach, although further studies need to be performed to evaluate whether certain groups of aneurysms are more likely to benefit from it. Further technological development is required to improve its user friendliness.

External validation of Vascular Study Group of New England risk predictive model of mortality after elective abdominal aorta aneurysm repair in the Vascular Quality Initiative and comparison against established models.

PubMed

Eslami, Mohammad H; Rybin, Denis V; Doros, Gheorghe; Siracuse, Jeffrey J; Farber, Alik

2018-01-01

The purpose of this study is to externally validate a recently reported Vascular Study Group of New England (VSGNE) risk predictive model of postoperative mortality after elective abdominal aortic aneurysm (AAA) repair and to compare its predictive ability across different patients' risk categories and against the established risk predictive models using the Vascular Quality Initiative (VQI) AAA sample. The VQI AAA database (2010-2015) was queried for patients who underwent elective AAA repair. The VSGNE cases were excluded from the VQI sample. The external validation of a recently published VSGNE AAA risk predictive model, which includes only preoperative variables (age, gender, history of coronary artery disease, chronic obstructive pulmonary disease, cerebrovascular disease, creatinine levels, and aneurysm size) and planned type of repair, was performed using the VQI elective AAA repair sample. The predictive value of the model was assessed via the C-statistic. Hosmer-Lemeshow method was used to assess calibration and goodness of fit. This model was then compared with the Medicare, Vascular Governance Northwest model, and Glasgow Aneurysm Score for predicting mortality in VQI sample. The Vuong test was performed to compare the model fit between the models. Model discrimination was assessed in different risk group VQI quintiles. Data from 4431 cases from the VSGNE sample with the overall mortality rate of 1.4% was used to develop the model. The internally validated VSGNE model showed a very high discriminating ability in predicting mortality (C = 0.822) and good model fit (Hosmer-Lemeshow P = .309) among the VSGNE elective AAA repair sample. External validation on 16,989 VQI cases with an overall 0.9% mortality rate showed very robust predictive ability of mortality (C = 0.802). Vuong tests yielded a significant fit difference favoring the VSGNE over then Medicare model (C = 0.780), Vascular Governance Northwest (0.774), and Glasgow Aneurysm Score (0.639). Across the 5 risk quintiles, the VSGNE model predicted observed mortality significantly with great accuracy. This simple VSGNE AAA risk predictive model showed very high discriminative ability in predicting mortality after elective AAA repair among a large external independent sample of AAA cases performed by a diverse array of physicians nationwide. The risk score based on this simple VSGNE model can reliably stratify patients according to their risk of mortality after elective AAA repair better than other established models. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Changes in blood flow due to stented parent artery expansion in an intracranial aneurysm.

PubMed

Mori, Futoshi; Ohta, Makoto; Matsuzawa, Teruo

2015-01-01

Stent placement is thought to obstruct the inflow of blood to an aneurysm. However, we introduced parent artery expansion and demonstrated that this may reduce the blood flow by the stent. In our previous study using idealized shapes, the results showed that flow reduction was greater than 22.2%, even if the expansion rate was only 6%. Furthermore, the parent artery expansion is predominantly caused by the effect of flow reduction as compared to that of flow reduction due to the obstruction of flow under stent placement. However, a realistic shape is complex and the blood flow also becomes complex flow. It is not understood whether the results of flow in the idealized shape are reflective of flow from a realistic 3D model. Therefore, we examined the effect of parent artery expansion using a realistic model. The aim is to clarify the effects of parent artery expansion on inflow rate, wall shear stress, and oscillatory shear index. We used a patient-specific geometry of a human internal carotid artery with an aneurysm. The geometry of parent artery expansion due to oversized stent constructed based on the voronoi diagram. We performed calculations in the unsteady-state situations using constructed models. The complexity of the flow in the aneurysm decreases in case of expanded parent artery. The inflow rate decreases by 33.6% immediately after parent artery expansion alone without a stent. The effect of the parent artery expansion on flow reduction is larger than that of the obstruction flow by stent placement. In addition, wall shear stress and oscillatory shear index on the aneurysm wall decrease by change in blood flow due to the parent artery expansion. The effects of the parent artery expansion in a realistic aneurysm model with different stent lengths were evaluated on the basis of a numerical simulation. Although the flow was complex, the parent artery expansion with stent reduces the inflow to the aneurysm and wall shear stress and oscillatory shear index on the aneurysm. Therefore, we suggest that changes in the blood flow because of the parent artery expansion may be identified and, sometimes, is more effective than the obstruction flow due to the stent placement.

Surgical and medical management of extracranial carotid artery aneurysms.

PubMed

Fankhauser, Grant T; Stone, William M; Fowl, Richard J; O'Donnell, Mark E; Bower, Thomas C; Meyer, Fredric B; Money, Samuel R

2015-02-01

Extracranial carotid artery aneurysms (ECCAs) are extremely rare with limited information about management options. Our purpose was to review our institution's experience with ECCAs during 15 years and to discuss the presentation and treatment of these aneurysms. A retrospective review of patients diagnosed with ECCAs from 1998 to 2012 was performed. Symptoms, risk factors, etiology, diagnostic methods, treatments, and outcomes were reviewed. During the study period, 141 aneurysms were diagnosed in 132 patients (mean age, 61 years; 69 men). There were 116 (82%) pseudoaneurysms and 25 (18%) true aneurysms; 69 (49%) aneurysms were asymptomatic, whereas 72 (52%) had symptoms (28 painless masses; 10 transient ischemic attacks; 10 vision symptoms; 9 ruptures; 8 strokes; 4 painful mass; 1 dysphagia; 1 tongue weakness; 1 bruit). Causes of true aneurysms included fibromuscular dysplasia in 15 patients, Ehlers-Danlos syndrome in three, Marfan syndrome in one, and uncharacterized connective tissue diseases in two. Of 25 true aneurysms, 11 (44%) were symptomatic; 15 (60%) true aneurysms underwent open surgical treatment, whereas 10 (40%) were managed nonoperatively. Postoperative complications included one stroke during a mean follow-up of 31 months (range, 0-166 months). No aneurysms managed nonoperatively required intervention during a mean follow-up of 77 months (range, 1-115 months). Of 116 pseudoaneurysms, 60 (52%) were symptomatic; 33 (29%) pseudoaneurysms underwent open surgery, 18 (15%) underwent endovascular intervention, and 65 (56%) were managed medically. Pseudoaneurysm after endarterectomy (28 patients; 24%) presented at a mean of 82 months from the surgical procedure. Mean follow-up for all aneurysms was 33.9 months. One (0.7%) aneurysm-related death occurred (rupture treated palliatively). No patient undergoing nonoperative management suffered death or major morbidity related to the aneurysm. Nonoperative management was more common in asymptomatic patients (71%) than in symptomatic patients (31%). ECCAs are uncommon and may be manifested with varying symptoms. All segments of the carotid artery are susceptible, although the internal is most commonly affected. Open surgical intervention was more common in patients with symptoms and with true aneurysms. Patients with pseudoaneurysms were more likely to undergo endovascular intervention. Nonoperative treatment is safe in selected patients. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Self-expandable macroporous nitinol stents for transfemoral exclusion of aortic aneurysms in dogs: preliminary results.

PubMed

Hagen, B; Harnoss, B M; Trabhardt, S; Ladeburg, M; Fuhrmann, H; Franck, C

1993-01-01

This experimental study evaluated the feasibility of excluding artificially created aortic aneurysms in dogs with transfemorally inserted nitinol stents, serving as intraluminal bypass. Infrarenal aortic aneurysms were created in eleven dogs (28-35 kg) by end-to-end anastomosis of sacciform conduits. Single and double wire-knitted, macroporous, superelastic, self-expanding nitinol stents without any additional wrapping or in-between fabrics served as endovascular grafts. The pore size of the double-knitted stents was less than 0.7 mm2. Angiography following stent placement showed immediate exclusion of the aneurysms for the double-knitted stents. For the single-knitted stents (2 cases), partial exclusion was achieved only after considerable delay. CT studies in the dogs with the double-knitted stents revealed patency of the grafts after 3 to 5 weeks with the aneurysms totally thrombosed. So far gross pathology of 1 dog at 24 h and 1 at 12 months revealed patency of the stents. At 12 months histopathology showed a neointima covering the inner stent surface with the aneurysm filled by an organized thrombus. It is concluded, that an "open" stent with a tight meshwork appears to be a suitable device to instantly exclude artificial aneurysms of the canine aorta.

Predictors of shunt-dependent hydrocephalus following aneurysmal subarachnoid hemorrhage: a pilot study in a single Egyptian institute.

PubMed

Aboul-Ela, Hashem M; Salah El-Din, Ahmed M; Zaater, Ahmed A; Shehab, Mohamed; El Shahawy, Ossama A

2018-01-01

Acute hydrocephalus can cause neurological deterioration after aneurysmal subarachnoid hemorrhage (aSAH). Predicting which patient would require shunting is challenging. This prospective study was conducted upon twenty patients who suffered acute hydrocephalus due to subarachnoid hemorrhage of ruptured aneurysms. Surgical or non-surgical management of hydrocephalus was conducted. Glasgow Coma scale (GCS) was assessed, and hydrocephalus was graded by bicaudate index. Fisher grade was determined from CT scan. Aneurysm site was determined by conventional or CT angiography. Either surgical clipping or endovascular coiling of aneurysms was performed. Initially, 3 (15%) patients had emergency CSF diversion on admission due to poor GCS on arrival. Initially, the remaining 17 patients were managed conservatively. Five patients did not require any intervention. Twelve patients had external ventricular drainage placement, 4 were weaned, and 8 failed weaning. High bicaudate index (> 0.2) correlated with shunting. Aneurysm site correlated well with shunting (ACoA or PCoA). Patients with fair GCS can be managed conservatively. Any deterioration warrants shifting to CSF diversion. Higher bicaudate index will usually need CSF diversion. The value of Fisher carries no significant value. Aneurysm location (ACoA or PCoA) correlates with an increased incidence of ventriculoperitoneal shunt placement.

Identification of vortex structures in a cohort of 204 intracranial aneurysms

PubMed Central

Trylesinski, Gabriel; Xiang, Jianping; Snyder, Kenneth; Meng, Hui

2017-01-01

An intracranial aneurysm (IA) is a cerebrovascular pathology that can lead to death or disability if ruptured. Abnormal wall shear stress (WSS) has been associated with IA growth and rupture, but little is known about the underlying flow physics related to rupture-prone IAs. Previous studies, based on analysis of a few aneurysms or partial views of three-dimensional vortex structures, suggest that rupture is associated with complex vortical flow inside IAs. To further elucidate the relevance of vortical flow in aneurysm pathophysiology, we studied 204 patient IAs (56 ruptured and 148 unruptured). Using objective quantities to identify three-dimensional vortex structures, we investigated the characteristics associated with aneurysm rupture and if these features correlate with previously proposed WSS and morphological characteristics indicative of IA rupture. Based on the Q-criterion definition of a vortex, we quantified the degree of the aneurysmal region occupied by vortex structures using the volume vortex fraction (vVF) and the surface vortex fraction (sVF). Computational fluid dynamics simulations showed that the sVF, but not the vVF, discriminated ruptured from unruptured aneurysms. Furthermore, we found that the near-wall vortex structures co-localized with regions of inflow jet breakdown, and significantly correlated to previously proposed haemodynamic and morphologic characteristics of ruptured IAs. PMID:28539480

Identification of vortex structures in a cohort of 204 intracranial aneurysms.

PubMed

Varble, Nicole; Trylesinski, Gabriel; Xiang, Jianping; Snyder, Kenneth; Meng, Hui

2017-05-01

An intracranial aneurysm (IA) is a cerebrovascular pathology that can lead to death or disability if ruptured. Abnormal wall shear stress (WSS) has been associated with IA growth and rupture, but little is known about the underlying flow physics related to rupture-prone IAs. Previous studies, based on analysis of a few aneurysms or partial views of three-dimensional vortex structures, suggest that rupture is associated with complex vortical flow inside IAs. To further elucidate the relevance of vortical flow in aneurysm pathophysiology, we studied 204 patient IAs (56 ruptured and 148 unruptured). Using objective quantities to identify three-dimensional vortex structures, we investigated the characteristics associated with aneurysm rupture and if these features correlate with previously proposed WSS and morphological characteristics indicative of IA rupture. Based on the Q -criterion definition of a vortex, we quantified the degree of the aneurysmal region occupied by vortex structures using the volume vortex fraction ( vVF ) and the surface vortex fraction ( sVF ). Computational fluid dynamics simulations showed that the sVF , but not the vVF , discriminated ruptured from unruptured aneurysms. Furthermore, we found that the near-wall vortex structures co-localized with regions of inflow jet breakdown, and significantly correlated to previously proposed haemodynamic and morphologic characteristics of ruptured IAs. © 2017 The Author(s).

Flow diverter device for the treatment of small middle cerebral artery aneurysms.

PubMed

Briganti, Francesco; Delehaye, Luigi; Leone, Giuseppe; Sicignano, Carmine; Buono, Giuseppe; Marseglia, Mariano; Caranci, Ferdinando; Tortora, Fabio; Maiuri, Francesco

2016-03-01

Experience with the endovascular treatment of middle cerebral artery (MCA) aneurysms by flow diverter devices (FDD) is still limited. This study examines the results and complications of FDD for small aneurysms at this location. From February 2010 to December 2013, 14 patients (10 women; mean age 59 years) with 15 small MCA aneurysms were treated with FDD. All procedures were performed with the Pipeline embolization device (PED). Complete occlusion was obtained in 12/15 aneurysms (80%) and partial occlusion in 3 (20%). Among 13 aneurysms with a side branch, this was patent at the angiographic control in 4 cases, showed decreased filling in 6, and was occluded in 3 (with neurological deficits in 2). All PEDs were patent at follow-up. Post-procedural ischemic complications occurred in 4 (27%) procedures with permanent neurological deficit (modified Rankin score 2) in 3 (21%). No early or delayed aneurysm rupture, no subarachnoid or intraparenchymal hemorrhage and no deaths occurred. Endovascular treatment with FDD is a relatively safe treatment for small MCA aneurysms resulting in a high occlusion rate. The findings of this study suggest that complete occlusion after endovascular treatment with FDD can be delayed (>6 months). Ischemic complications may occur as early or delayed, particularly at clopidogrel interruption. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Postprocedural, midterm, and long-term results of cerebral aneurysms treated with flow-diverter devices: 7-year experience at a single center.

PubMed

Briganti, Francesco; Leone, Giuseppe; Cirillo, Luigi; de Divitiis, Oreste; Solari, Domenico; Cappabianca, Paolo

2017-06-01

OBJECTIVE Flow diversion has emerged as a viable treatment option for selected intracranial aneurysms and recently has been gaining traction. The aim of this study was to evaluate the safety and effectiveness of flow-diverter devices (FDDs) over a long-term follow-up period. METHODS The authors retrospectively reviewed all cerebral aneurysm cases that had been admitted to the Division of Neurosurgery of the Università degli Studi di Napoli between November 2008 and November 2015 and treated with an FDD. The records of 60 patients (48 females and 12 males) harboring 69 cerebral aneurysms were analyzed. The study end points were angiographic evidence of complete aneurysm occlusion, recanalization rate, occlusion of the parent artery, and clinical and radiological evidence of brain ischemia. The occlusion rate was evaluated according to the O'Kelly-Marotta (OKM) Scale for flow diversion, based on the degree of filling (A, total filling; B, subtotal filling; C, entry remnant; D, no filling). Postprocedural, midterm, and long-term results were strictly analyzed. RESULTS Complete occlusion (OKM D) was achieved in 63 (91%) of 69 aneurysms, partial occlusion (OKM C) in 4 (6%), occlusion of the parent artery in 2 (3%). Intraprocedural technical complications occurred in 3 patients (5%). Postprocedural complications occurred in 6 patients (10%), without neurological deficits. At the 12-month follow-up, 3 patients (5%) experienced asymptomatic cerebral infarction. No further complications were observed at later follow-up evaluations (> 24 months). There were no reports of any delayed aneurysm rupture, subarachnoid or intraparenchymal hemorrhage, ischemic complications, or procedure- or device-related deaths. CONCLUSIONS Endovascular treatment with an FDD is a safe treatment for unruptured cerebral aneurysms, resulting in a high rate of occlusion. In the present study, the authors observed effective and stable aneurysm occlusion, even at the long-term follow-up. Data in this study also suggest that ischemic complications can occur at a later stage, particularly at 12-18 months. On the other hand, no other ischemic or hemorrhagic complications occurred beyond 24 months.

Role of C-arm VasoCT in the use of endovascular WEB flow disruption in intracranial aneurysm treatment.

PubMed

Caroff, J; Mihalea, C; Neki, H; Ruijters, D; Ikka, L; Benachour, N; Moret, J; Spelle, L

2014-07-01

The WEB aneurysm embolization system is still under evaluation but seems to be a promising technique to treat wide-neck bifurcation aneurysms. However, this device is barely visible using conventional DSA; thus, high-resolution contrast-enhanced flat panel detector CT (VasoCT) may be useful before detachment to assess the sizing and positioning of the WEB. The purpose of this study was to evaluate the interest of VasoCT during WEB procedures. From March 2012 to July 2013, twelve patients (10 women and 2 men; age range, 44-55 years) were treated for 13 intracranial aneurysms with the WEB device. DSA and VasoCT were used and compared to depict any protrusion of the device in parent arteries before detachment. Two neuroradiologists reviewed each VasoCT scan, and the quality was graded on a subjective quality scale. The mesh of the WEB was very well-depicted in all cases, allowing a very good assessment of its deployment. Device protrusion was clearly detected with VasoCT in 5 cases, leading to WEB repositioning or size substitution. During follow-up, VasoCT also allows good assessment of eventual residual blood flow inside the aneurysm or the WEB device. Unlike DSA, VasoCT is an excellent tool to assess WEB deployment and positioning. In our experience, it allowed a precise evaluation of the WEB sizing and its relation to the parent vessel. Such information very likely enhances the ability to safely use this device, avoiding potential thromboembolic events in cases of protrusion in the parent arteries. © 2014 by American Journal of Neuroradiology.

Stent-assisted coiling of wide-neck bifurcation aneurysms with a branch incorporated in the aneurysm base: long-term follow-up in 49 patients with 53 aneurysms.

PubMed

Lubicz, Boris; Morais, Ricardo; Bruyère, Pierre-Julien; Ligot, Noémie; Mine, Benjamin

2017-06-01

Wide-neck bifurcation intracranial aneurysms (WNBA) with a branch incorporated in the aneurysm base remain difficult to treat by embolization. We aim to report our long-term follow-up of stent-assisted coiling (SAC) in this subgroup of patients. This study was approved by our local ethical committee. A retrospective review of our prospectively maintained database identified all patients treated in our institution by SAC for a WNBA with a branch incorporated in the aneurysm base. Technical issues, immediate, long-term outcomes were evaluated. Between 2007 and 2015, 49 patients with 53 intracranial aneurysms (IAs) (52 unruptured, 1 ruptured) were identified and successfully treated. No morbidity/mortality occurred. The incorporated branch was preserved in all patients but one who was treated during a vasospasm phase. At the first 6-month imaging control, the branch was patent. Immediate occlusion was near-complete in 11/53 aneurysms (20.8%), neck remnant in 20/53 aneurysms (37.7%), and incomplete in 22/53 aneurysms (41.5%). Available imaging follow-up of 47 IAs, ranging from 3 to 84 months (mean 26 months ± 19.6 months), showed 27 progressive thrombosis (57.4%), 17 stable occlusions (36.2%), 1 minor recanalization (2.1%), and 2 significant recanalizations that were retreated (4.3%). The latest imaging control showed 30 near-complete occlusions (63.8%), 13 neck remnants (27.7%), and 4 incomplete occlusions (8.5%). Stent-assisted coiling is safe and effective for the treatment of WNBA with a branch incorporated in the aneurysm base. Despite poor immediate anatomical results, long-term follow-up shows a high rate of progressive thrombosis achieving adequate and stable occlusion in most patients.

In vitro strain measurements in cerebral aneurysm models for cyber-physical diagnosis.

PubMed

Shi, Chaoyang; Kojima, Masahiro; Anzai, Hitomi; Tercero, Carlos; Ikeda, Seiichi; Ohta, Makoto; Fukuda, Toshio; Arai, Fumihito; Najdovski, Zoran; Negoro, Makoto; Irie, Keiko

2013-06-01

The development of new diagnostic technologies for cerebrovascular diseases requires an understanding of the mechanism behind the growth and rupture of cerebral aneurysms. To provide a comprehensive diagnosis and prognosis of this disease, it is desirable to evaluate wall shear stress, pressure, deformation and strain in the aneurysm region, based on information provided by medical imaging technologies. In this research, we propose a new cyber-physical system composed of in vitro dynamic strain experimental measurements and computational fluid dynamics (CFD) simulation for the diagnosis of cerebral aneurysms. A CFD simulation and a scaled-up membranous silicone model of a cerebral aneurysm were completed, based on patient-specific data recorded in August 2008. In vitro blood flow simulation was realized with the use of a specialized pump. A vision system was also developed to measure the strain at different regions on the model by way of pulsating blood flow circulating inside the model. Experimental results show that distance and area strain maxima were larger near the aneurysm neck (0.042 and 0.052), followed by the aneurysm dome (0.023 and 0.04) and finally the main blood vessel section (0.01 and 0.014). These results were complemented by a CFD simulation for the addition of wall shear stress, oscillatory shear index and aneurysm formation index. Diagnosis results using imaging obtained in August 2008 are consistent with the monitored aneurysm growth in 2011. The presented study demonstrates a new experimental platform for measuring dynamic strain within cerebral aneurysms. This platform is also complemented by a CFD simulation for advanced diagnosis and prediction of the growth tendency of an aneurysm in endovascular surgery. Copyright © 2013 John Wiley & Sons, Ltd.

Validation of real-time three-dimensional echocardiography for quantifying left ventricular volumes in the presence of a left ventricular aneurysm: in vitro and in vivo studies

NASA Technical Reports Server (NTRS)

Qin, J. X.; Jones, M.; Shiota, T.; Greenberg, N. L.; Tsujino, H.; Firstenberg, M. S.; Gupta, P. C.; Zetts, A. D.; Xu, Y.; Ping Sun, J.;

Risk factors and consequences of unexpected trapping for ruptured anterior communicating artery aneurysms

PubMed Central

Fukuda, Hitoshi; Iwasaki, Koichi; Murao, Kenichi; Yamagata, Sen; Lo, Benjamin W.Y.; Macdonald, R. Loch

2014-01-01

Background: While clipping cerebral aneurysms at the neck is optimal, in some cases this is not possible and other strategies are necessary. The purpose of this study was to describe the incidence, risk factors, and outcomes for inability to clip reconstruct ruptured anterior communicating artery (ACoA) aneurysms. Methods: Of the 70 cases of ruptured ACoA aneurysms between January 2006 and December 2013, our institutional experience revealed four cases of small ACoA aneurysms that had been considered clippable prior to operation but required trapping. When a unilateral A2 segment of anterior cerebral artery (ACA) was compromised by trapping, revascularization was performed by bypass surgery. Clinical presentation, angiographic characteristics, operative approach, intraoperative findings, and treatment outcomes were assessed. Results: Very small aneurysm under 3 mm was a risk factor for unexpected trapping. The reason for unexpected trapping was laceration of the aneurysmal neck in two cases, and lack of clippaple component due to disintegration of entire aneurysmal wall at the time of rupture in the others. Aneurysms with bilateral A1 were treated with sole trapping through pterional approach in two cases. The other two cases had hypoplastic unilateral A1 segment of ACA and were treated with combination of aneurysm trapping and revascularization of A2 segment of ACA through interhemispheric approach. No patients had new cerebral infarctions of cortical ACA territory from surgery. Cognitive dysfunction was observed in three cases, but all patients became independent at 12-month follow up. Conclusions: Unexpected trapping was performed when ruptured ACoA aneurysms were unclippable. Trapping with or without bypass can result in reasonable outcomes, with acceptable risk of cognitive dysfunction. PMID:25101201

Relationship between aneurysm occlusion and flow diverting device oversizing in a rabbit model.

PubMed

Hodis, Simona; Ding, Yong-Hong; Dai, Daying; Lingineni, Ravi; Mut, Fernando; Cebral, Juan; Kallmes, David; Kadirvel, Ramanathan

2016-01-01

Implanted, actual flow diverter pore density is thought to be strongly influenced by proper matching between the device size and parent artery diameter. The objective of this study was to characterize the correlation between device sizing, metal coverage, and the resultant occlusion of aneurysms following flow diverter treatment in a rabbit model. Rabbit saccular aneurysms were treated with flow diverters (iso-sized to proximal parent artery, 0.5 mm oversized, or 1.0 mm oversized, respectively, n=6 for each group). Eight weeks after implantation, the angiographic degree of aneurysm occlusion was graded (complete, near-complete, or incomplete). The ostium of the explanted aneurysm covered with the flow diverter struts was photographed. Based on gross anatomic findings, the metal coverage and pore density at the ostium of the aneurysm were calculated and correlated with the degree of aneurysm occlusion. Angiographic results showed there were no statistically significant differences in aneurysm geometry and occlusion among groups. The mean parent artery diameter to flow diverter diameter ratio was higher in the 1.0 mm oversized group than in the other groups. Neither the percentage metal coverage nor the pore density showed statistically significant differences among groups. Aneurysm occlusion was inversely correlated with the ostium diameter, irrespective of the size of the device implanted. Device sizing alone does not predict resultant pore density or metal coverage following flow diverter implantation in the rabbit aneurysm model. Aneurysm occlusion was not impacted by either metal coverage or pore density, but was inversely correlated with the diameter of the ostium. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

The 100 most cited articles in the endovascular management of intracranial aneurysms.

PubMed

Maingard, Julian; Phan, Kevin; Ren, Yifan; Kok, Hong Kuan; Thijs, Vincent; Hirsch, Joshua A; Lee, Michael J; Chandra, Ronil V; Brooks, Duncan Mark; Asadi, Hamed

2018-01-19

Endovascular interventions for intracranial aneurysms have evolved substantially over the past several decades. A citation rank list is used to measure the scientific and/or clinical impact of an article. Our objective was to identify and analyze the characteristics of the 100 most cited articles in the field of endovascular therapy for intracranial aneurysms. We performed a retrospective bibliometric analysis between July and August 2017. Articles were searched on the Science Citation Index Expanded database using Web of Science in order to identify the most cited articles in the endovascular therapy of intracranial aneurysms since 1945. Using selected key terms ('intracranial aneurysm', 'aneurysm', 'aneurysmal subarachnoid', 'endovascular', 'coiling', 'stent-assisted', 'balloon-assisted', 'flow-diversion') yielded a total of 16 314 articles. The top 100 articles were identified and analyzed to extract relevant information, including citation count, authorship, article type, subject matter, institution, country of origin, and year of publication. Citations for the top 100 articles ranged from 133 to 1832. All articles were cited an average of 27 times per year. There were 45 prospective studies, including 7 level-II randomized controlled trials. Most articles were published in the 2000s (n=53), and the majority constituted level III or level IV evidence. Half of the top 100 articles arose from the USA. This study provides a comprehensive overview of the most cited articles in the endovascular management of intracranial aneurysms. It recognizes the contributions made by key authors and institutions, providing an important framework to an enhanced understanding of the evidence behind the endovascular treatment of aneurysms. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A microfabricated microfluidic bioMEMS device to model human brain aneurisms: the aneurysm-on-a-chip

NASA Astrophysics Data System (ADS)

Reece, Lisa M.; Khor, Jian Wei; Thakur, Raviraj; Amin, Ahmed; Wereley, Steven T.; Leary, James F.

2015-03-01

Aneurysms are pockets of blood that collect outside blood vessel walls forming dilatations and leaving arterial walls very prone to rupture. There is little information concerning the causes of intracranial aneurysm formation, growth, and rupture. Current treatments include: (1) clipping, and (2) coil embolization, including stent-assisted coiling. Further, the evolution of any aneurysm is assumed to be caused by the remodeling of the affected blood vessel's material constituents (tunica intima, tunica media, or tunica adventitia). Velocity, pressure, and wall shear stresses aid in the disease development of aneurysmal growth, while the shear force mechanisms effecting wound closure are elusive. To study aneurysm pathogenesis, a lab-on-a-chip device is the key to discovering the underlying mechanisms of these lesions. A two-dimensional microfluidic model, the Aneurysm-on-a-Chip™ (AOC), was the logical answer to study particle flow within an aneurysm "sac". The AOC apparatus can track particles/cells when it is coupled to particle image velocimetry software (PIV) package. The AOC fluid flow was visualized using standard microscopy techniques with commercial microparticles and human aortic smooth muscle cells (HASMC). Images were taken during fluid flow experiments and PIV was utilized to monitor the flow of particles within the "sac" region, as well as particles entering and exiting the device. Quiver plots were generated from fluid flow experiments using standard 7 μm latex particles and fixed HASMC in PBS. PIV analysis shows that the particles flowed nicely from input to output. Wall shear stress provided evidence that there was some back flow at the edges of the "sac" - an indicator of aneurysm development in human patients.

Endovascular treatment of a true posterior communicating artery aneurysm

PubMed Central

Munarriz, Pablo M.; Castaño-Leon, Ana M.; Cepeda, Santiago; Campollo, Jorge; Alén, Jose F.; Lagares, Alfonso

2014-01-01

Background: Posterior communicating artery (PCoA) aneurysms are most commonly located at the junction of the internal carotid artery and the PCoA. “True” PCoA aneurysms, which originate from the PCoA itself, are rarely encountered. Most previously reported cases were treated surgically mainly before the endovascular option became available. Case Description: A 53-year-old male presented with sudden onset of right hemiparesis and aphasia. Left middle cerebral artery stroke was diagnosed. Further studies revealed a 3 mm left PCoA aneurysm arising from the PCoA itself, attached to neither the internal carotid artery nor the posterior cerebral artery. Endovascular treatment was performed and the aneurysm was coiled completely. Conclusion: Technical advances in endovascular interventional technology have permitted an additional approach to these lesions. The possible endovascular significance of the treatment of true PCoA aneurysms is discussed. PMID:25422786

Cerebral aneurysms: Formation, progression and developmental chronology

PubMed Central

Etminan, Nima; Buchholz, Bruce A.; Dreier, Rita; Bruckner, Peter; Torner, James C.; Steiger, Hans-Jakob; Hänggi, Daniel; Macdonald, R. Loch

2015-01-01

The prevalence of unruptured intracranial aneurysms (UAIs) in the general population is up to 3%. Existing epidemiological data suggests that only a small fraction of UIAs progress towards rupture over the lifetime of an individual, but the surrogates for subsequent rupture and the natural history of UIAs are discussed very controversially at present. In case of rupture of an UIA, the case-fatality is up to 50%, which therefore continues to stimulate interest in the pathogenesis of cerebral aneurysm formation and progression. Actual data on the chronological development of cerebral aneurysm has been especially difficult to obtain and, until recently, the existing knowledge in this respect is mainly derived from animal or mathematical models or short-term observational studies. Here, we highlight the current data on cerebral aneurysm formation and progression as well as a novel approach to investigate the developmental chronology of cerebral aneurysms. PMID:24323717

Acute postoperative neurological deterioration associated with surgery for ruptured intracranial aneurysm: incidence, predictors, and outcomes.

PubMed

Mahaney, Kelly B; Todd, Michael M; Bayman, Emine O; Torner, James C

2012-06-01

Subarachnoid hemorrhage (SAH) results in significant morbidity and mortality, even among patients who reach medical attention in good neurological condition. Many patients have neurological decline in the perioperative period, which contributes to long-term outcomes. The focus of this study is to characterize the incidence of, characteristics predictive of, and outcomes associated with acute postoperative neurological deterioration in patients undergoing surgery for ruptured intracranial aneurysm. The Intraoperative Hypothermia for Aneurysm Surgery Trial (IHAST) was a multicenter randomized clinical trial that enrolled 1001 patients and assesssed the efficacy of hypothermia as neuroprotection during surgery to secure a ruptured intracranial aneurysm. All patients had a radiographically confirmed SAH, were classified as World Federation of Neurosurgical Societies (WFNS) Grade I-III immediately prior to surgery, and underwent surgery to secure the ruptured aneurysm within 14 days of SAH. Neurological assessment with the National Institutes of Health Stroke Scale (NIHSS) was performed preoperatively, at 24 and 72 hours postoperatively, and at time of discharge. The primary outcome variable was a dichotomized scoring based on an IHAST version of the Glasgow Outcome Scale (GOS) in which a score of 1 represents a good outcome and a score > 1 a poor outcome, as assessed at 90-days' follow-up. Data from IHAST were analyzed for occurrence of a postoperative neurological deterioration. Preoperative and intraoperative variables were assessed for associations with occurrence of postoperative neurological deterioration. Differences in baseline, intraoperative, and postoperative variables and in outcomes between patients with and without postoperative neurological deterioration were compared with Fisher exact tests. The Wilcoxon rank-sum test was used to compare variables reported as means. Multiple logistic regression was used to adjust for covariates associated with occurrence of postoperative deficit. Acute postoperative neurological deterioration was observed in 42.6% of the patients. New focal motor deficit accounted for 65% of postoperative neurological deterioration, while 60% was accounted for using the NIHSS total score change and 51% by Glasgow Coma Scale score change. Factors significantly associated with occurrence of postoperative neurological deterioration included: age, Fisher grade on admission, occurrence of a procedure prior to aneurysm surgery (ventriculostomy), timing of surgery, systolic blood pressure during surgery, ST segment depression during surgery, history of abnormality in cardiac valve function, use of intentional hypotension during surgery, duration of anterior cerebral artery occlusion, intraoperative blood loss, and difficulty of aneurysm exposure. Of the 426 patients with postoperative neurological deterioration at 24 hours after surgery, only 46.2% had a good outcome (GOS score of 1) at 3 months, while 77.7% of those without postoperative neurological deterioration at 24 hours had a good outcome (p < 0.05). Neurological injury incurred perioperatively or in the acute postoperative period accounts for a large percentage of poor outcomes in patients with good admission WFNS grades undergoing surgery for aneurysmal SAH. Avoiding surgical factors associated with postoperative neurological deterioration and directing investigative efforts at developing improved neuroprotection for use in aneurysm surgery may significantly improve long-term neurological outcomes in patients with SAH.

Emergency abdominal aortic aneurysm repair with a preferential endovascular strategy: mortality and cost-effectiveness analysis.

PubMed

Kapma, Marten R; Groen, Henk; Oranen, Bjorn I; van der Hilst, Christian S; Tielliu, Ignace F; Zeebregts, Clark J; Prins, Ted R; van den Dungen, Jan J; Verhoeven, Eric L

2007-12-01

To assess mortality and treatment costs of a new management protocol with preferential use of emergency endovascular aneurysm repair (eEVAR) for acute abdominal aortic aneurysm (AAA). From September 2003 until February 2005, 49 consecutive patients (45 men; mean age 71 years) with acute AAA were entered into a prospective study of a new management protocol that featured preferential use of eEVAR (n=18); patients with unsuitable anatomy or who were hemodynamically unstable underwent open repair (n=31). Mortality data and costs of treatment were compared in this mixed prospective group to a historical control group consisting of 147 patients (128 men; mean age 71 years) who underwent open repair from January 1998 to December 2001. All direct medical costs were included from the moment of admission until discharge from the hospital. Mortality in the mixed prospective group (18%) was lower than in the historical control group (31%), but the difference did not reach statistical significance (p=0.099). The mean total cost in the mixed prospective group was 17,164 euro compared to 21,084 euro in the historical open repair group (p=0.255). A preferential eEVAR protocol for acute AAA can decrease mortality and does not increase overall costs during initial treatment, but larger studies are needed to determine if these trends are statistically significant.

Strain measurement of abdominal aortic aneurysm with real-time 3D ultrasound speckle tracking.

PubMed

Bihari, P; Shelke, A; Nwe, T H; Mularczyk, M; Nelson, K; Schmandra, T; Knez, P; Schmitz-Rixen, T

2013-04-01

Abdominal aortic aneurysm rupture is caused by mechanical vascular tissue failure. Although mechanical properties within the aneurysm vary, currently available ultrasound methods assess only one cross-sectional segment of the aorta. This study aims to establish real-time 3-dimensional (3D) speckle tracking ultrasound to explore local displacement and strain parameters of the whole abdominal aortic aneurysm. Validation was performed on a silicone aneurysm model, perfused in a pulsatile artificial circulatory system. Wall motion of the silicone model was measured simultaneously with a commercial real-time 3D speckle tracking ultrasound system and either with laser-scan micrometry or with video photogrammetry. After validation, 3D ultrasound data were collected from abdominal aortic aneurysms of five patients and displacement and strain parameters were analysed. Displacement parameters measured in vitro by 3D ultrasound and laser scan micrometer or video analysis were significantly correlated at pulse pressures between 40 and 80 mmHg. Strong local differences in displacement and strain were identified within the aortic aneurysms of patients. Local wall strain of the whole abdominal aortic aneurysm can be analysed in vivo with real-time 3D ultrasound speckle tracking imaging, offering the prospect of individual non-invasive rupture risk analysis of abdominal aortic aneurysms. Copyright © 2013 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

A two-system, single-analysis, fluid-structure interaction technique for modelling abdominal aortic aneurysms.

PubMed

Kelly, S C; O'Rourke, M J

2010-01-01

This work reports on the implementation and validation of a two-system, single-analysis, fluid-structure interaction (FSI) technique that uses the finite volume (FV) method for performing simulations on abdominal aortic aneurysm (AAA) geometries. This FSI technique, which was implemented in OpenFOAM, included fluid and solid mesh motion and incorporated a non-linear material model to represent AAA tissue. Fully implicit coupling was implemented, ensuring that both the fluid and solid domains reached convergence within each time step. The fluid and solid parts of the FSI code were validated independently through comparison with experimental data, before performing a complete FSI simulation on an idealized AAA geometry. Results from the FSI simulation showed that a vortex formed at the proximal end of the aneurysm during systolic acceleration, and moved towards the distal end of the aneurysm during diastole. Wall shear stress (WSS) values were found to peak at both the proximal and distal ends of the aneurysm and remain low along the centre of the aneurysm. The maximum von Mises stress in the aneurysm wall was found to be 408kPa, and this occurred at the proximal end of the aneurysm, while the maximum displacement of 2.31 mm occurred in the centre of the aneurysm. These results were found to be consistent with results from other FSI studies in the literature.

Atrial septal aneurysm--a potential cause of systemic embolism. An echocardiographic study.

PubMed Central

Gallet, B; Malergue, M C; Adams, C; Saudemont, J P; Collot, A M; Druon, M C; Hiltgen, M

1985-01-01

Atrial septal aneurysm is an uncommon condition. Between 1981 and 1984 10 cases of atrial septal aneurysm were diagnosed by real time cross sectional echocardiography performed in 4840 patients. The aneurysm was associated either with mitral valve prolapse (three patients) or with atrial septal defect (three patients) or occurred in isolation (four patients, two of whom had had a previous embolic event leading to the diagnosis of atrial septal aneurysm by cross sectional echocardiography). During cross sectional echocardiography the aneurysm appeared as a localised bulging of the interatrial septum, which was best seen in the subcostal four chamber view and in the parasternal short axis view at the level of the aortic root. The aneurysm either protruded into only the right atrium (five patients) or moved backwards and forwards between the right and the left atria during the cardiac cycle (five patients). This motion pattern might be related to changes in the interatrial pressure gradient. The two patients who had had a systemic embolism were given anticoagulant treatment, but none underwent surgery. It is concluded that the true prevalence of atrial septal aneurysm might have been underestimated before the routine use of cross sectional echocardiography, that cross sectional echocardiography enables definitive diagnosis of this condition by a non-invasive technique, and that an atrial septal aneurysm should be suspected and looked for by cross sectional echocardiography after an unexplained systemic embolism. Images PMID:3970786

F2-isoprostanes and F4-neuroprostanes as markers of intracranial aneurysm development.

PubMed

Syta-Krzyżanowska, Anna; Jarocka-Karpowicz, Iwona; Kochanowicz, Jan; Turek, Grzegorz; Rutkowski, Robert; Gorbacz, Krzysztof; Mariak, Zenon; Skrzydlewska, Elżbieta

2018-04-24

Intracranial aneurysms are common, occurring in about 1-2% of the population. Saccular aneurysm is a pouch-like pathological dilatation of an intracranial artery that develops when the cerebral artery wall becomes too weak to resist hemodynamic pressure and distends. The aim of this study was to determine whether the development of intracranial aneurysms and subarachnoid hemorrhage (SAH) affects neuronal phospholipid metabolism, and what influence different invasive treatments have on brain free radical phospholipid metabolism. The level of polyunsaturated fatty acid (PUFA) cyclization products - F2-isoprostanes and F4-neuroprostanes - was examined using liquid chromatography - mass spectrometry (LC-MS) in the plasma of patients with brain aneurysm and resulting subarachnoid hemorrhage. It was revealed that an aneurysm leads to the enhancement of lipid peroxidation with a significant increase in plasma F2-isoprostanes and F4-neuroprostanes (more than 3-fold and 11-fold, respectively) in comparison to healthy subjects. The rupture of an aneurysm results in hemorrhage and an additional increase in examined prostaglandin derivatives. The embolization and clipping of aneurysms contribute to a gradual restoration of metabolic homeostasis in brain cells, which is visible in the decrease in PUFA cyclization products. The results indicate that aneurysm development is associated with enhanced inflammation and oxidative stress, factors which favor lipid peroxidation, particularly in neurons, whose membranes are rich in docosahexaenoic acid, a precursor of F4-neuroprostanes.

The natural history of splanchnic artery aneurysms and outcomes after operative intervention.

PubMed

Corey, Michael R; Ergul, Emel A; Cambria, Richard P; English, Sean J; Patel, Virendra I; Lancaster, R Todd; Kwolek, Christopher J; Conrad, Mark F

2016-04-01

Splanchnic artery aneurysms (SAAs) are uncommon, and standards for surveillance and intervention are lacking. The goal of this study was to review our 20-year experience with managing SAAs. The Research Patient Data Registry at the Massachusetts General Hospital was queried, and all patients with SAAs identified by axial imaging from 1994 to 2014 were included. Aneurysms were stratified into two cohorts: those that underwent early intervention (<6 months after lesion discovery) and those that received surveillance. Primary study end points included aneurysm growth or rupture during surveillance and patient 30-day morbidity or mortality after aneurysm repair. There were 264 SAAs identified in 250 patients. In 166 patients, 176 SAAs (66.6%) were placed into the surveillance cohort; 38 SAAs (21.6%) did not have subsequent axial imaging and were considered lost to follow-up. Mean aneurysm size in the surveillance cohort at first imaging study was 16.28 mm (8-41 mm), and mean surveillance time was 36.1 months (2-155 months); 126 SAAs (91.3%) remained stable in size over time, and 8 SAAs (5.8%) required intervention for aneurysm growth after a mean of 24 months. There were no ruptures in the surveillance cohort. There were 88 SAAs (33.3%) repaired early. Mean size of SAAs that were repaired early was 31.1 mm (10-140 mm). For intact SAAs, 30-day morbidity and mortality rates after repair were 13% and 3%, respectively. In the early repair cohort, 13 SAAs (14.7%) were ruptured at presentation. The 30-day morbidity and mortality rates after rupture were 54% and 8%, respectively. Five ruptured SAAs (38%) were anatomically located in the pancreaticoduodenal arcade. On univariate analysis, pancreaticoduodenal aneurysms were strongly associated with rupture (P = .0002). Small SAAs (≤25 mm) are not prone to significant expansion and do not require frequent surveillance imaging. Imaging every 3 years for small SAAs is adequate. Aneurysms of the pancreaticoduodenal arcade and gastroduodenal aneurysms are more likely to rupture and therefore warrant a more aggressive interventional approach. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

Aortic elongation in aortic aneurysm and dissection: the Tübingen Aortic Pathoanatomy (TAIPAN) project.

PubMed

Krüger, Tobias; Sandoval Boburg, Rodrigo; Lescan, Mario; Oikonomou, Alexandre; Schneider, Wilke; Vöhringer, Luise; Lausberg, Henning; Bamberg, Fabian; Blumenstock, Gunnar; Schlensak, Christian

2018-01-24

To study the lengths and diameters of aortic segments in healthy and diseased aortas and to assess the role of aortic elongation in Type A aortic dissection (TAD) prediction. Ectasia and aneurysm were defined by ascending aorta diameters of 45-54 mm and ≥55 mm, respectively. Computed tomography angiography studies of 256 healthy, 102 ectasia, 38 aneurysm, 17 pre-TAD and 166 TAD aortas were analysed using curved multiplanar reformats. The study groups were structurally equal. The diameter of the ascending aorta was 35 mm in the control group and was larger (P < 0.001) in the pre-TAD (43 mm) and TAD (56 mm) groups. The length of the ascending aorta from the aortic annulus to the brachiocephalic trunk was 92 mm in the control group, 113 mm in the ectasia group, 120 mm in the aneurysm group and 111 mm and 118 mm in the pre-TAD and TAD groups (all P < 0.001 compared with the control group). An ascending aorta length of 120 mm was exceeded in 2% of the control group, 31% of the ectasia group, 50% of the aneurysm group, 24% of the pre-TAD group and 48% of the TAD group. The correlation between the diameter and the length of the ascending aorta was r = 0.752; therefore, both parameters must be examined separately. A score considering both parameters identified 23.5% of pre-TAD patients, significantly more than the diameter alone, and 31.4% of ectasia aortas were elongated. Patients with ectatic (45-54 mm diameter) and elongated (≥120 mm) ascending aortas represent a high-risk subpopulation for TAD. © The Author(s) 2018. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Thinner regions of intracranial aneurysm wall correlate with regions of higher wall shear stress: a 7.0 tesla MRI

PubMed Central

Blankena, Roos; Kleinloog, Rachel; Verweij, Bon H.; van Ooij, Pim; ten Haken, Bennie; Luijten, Peter R.; Rinkel, Gabriel J.E.; Zwanenburg, Jaco J.M.

2016-01-01

Purpose To develop a method for semi-quantitative wall thickness assessment on in vivo 7.0 tesla (7T) MRI images of intracranial aneurysms for studying the relation between apparent aneurysm wall thickness and wall shear stress. Materials and Methods Wall thickness was analyzed in 11 unruptured aneurysms in 9 patients, who underwent 7T MRI with a TSE based vessel wall sequence (0.8 mm isotropic resolution). A custom analysis program determined the in vivo aneurysm wall intensities, which were normalized to signal of nearby brain tissue and were used as measure for apparent wall thickness (AWT). Spatial wall thickness variation was determined as the interquartile range in AWT (the middle 50% of the AWT range). Wall shear stress was determined using phase contrast MRI (0.5 mm isotropic resolution). We performed visual and statistical comparisons (Pearson’s correlation) to study the relation between wall thickness and wall shear stress. Results 3D colored AWT maps of the aneurysms showed spatial AWT variation, which ranged from 0.07 to 0.53, with a mean variation of 0.22 (a variation of 1.0 roughly means a wall thickness variation of one voxel (0.8mm)). In all aneurysms, AWT was inversely related to WSS (mean correlation coefficient −0.35, P<0.05). Conclusions A method was developed to measure the wall thickness semi-quantitatively, using 7T MRI. An inverse correlation between wall shear stress and AWT was determined. In future studies, this non-invasive method can be used to assess spatial wall thickness variation in relation to pathophysiologic processes such as aneurysm growth and –rupture. PMID:26892986

Treatment of recurrent aneurysms using the Woven EndoBridge (WEB): anatomical and clinical results.

PubMed

Gawlitza, Matthias; Soize, Sebastien; Januel, Anne-Christine; Mihalea, Cristian; Metaxas, Georgios-Emmanouil; Cognard, Christophe; Pierot, Laurent

2018-07-01

The safety and efficacy of the Woven EndoBridge (WEB) for the treatment of naïve intracranial aneurysms has been confirmed. To analyze the safety and efficacy of the WEB in the treatment of recurrent aneurysms. Anatomical and clinical results in consecutive patients with a recurrent aneurysm, who were treated using the WEB device in two French neurointerventional centers, were evaluated. Seventeen patients with 17 aneurysms were included. Treatment was feasible in 16 patients. In seven patients (41.2%), ancillary devices were used. Permanent morbidity due to a thromboembolic complication occurred in one patient (5.9%). There was no mortality. Follow-up angiographic studies were available for 15 patients after a mean of 12.1±6.1 months. Rates of complete occlusion, neck remnant, and aneurysm remnant were 33.3%, 40.0%, and 26.7%, respectively. Treatment of recurrent aneurysms using the WEB device may be reasonably safe and effective. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Aneurysm of the intradural artery of Adamkiewicz treated with muslin wrapping: technical case report.

PubMed

Vishteh, A G; Brown, A P; Spetzler, R F

1997-01-01

An exceedingly rare, isolated spinal arterial aneurysm and its management are presented. A 30-year-old man who presented with severe lower back pain and headache underwent a computed tomographic study of his head that disclosed nothing abnormal and a lumbar puncture that revealed bloody, xanthochromic cerebrospinal fluid. The findings from cerebral angiography were normal, and the results from spinal angiography were consistent with a diagnosis of an aneurysm of the artery of Adamkiewicz. A transthoracic approach with a partial T11 vertebrectomy gained exposure to this anteriorly located lesion. A fusiform aneurysm of the intradural portion of the artery of Adamkiewicz was discovered. Excision of the aneurysm with a vascular bypass was deemed impossible. The lesion was treated with muslin wrapping. One year after surgery, the patient remains at his baseline neurological condition. A review of the literature revealed only one other reported case of a ruptured aneurysm of the artery of Adamkiewicz, which was discovered postmortem. Therefore, this case represents the first report of a diagnosed and treated artery of Adamkiewicz aneurysm.

Identification of EGFLAM, SPATC1L and RNASE13 as novel susceptibility loci for aortic aneurysm in Japanese individuals by exome-wide association studies

PubMed Central

Yamada, Yoshiji; Sakuma, Jun; Takeuchi, Ichiro; Yasukochi, Yoshiki; Kato, Kimihiko; Oguri, Mitsutoshi; Fujimaki, Tetsuo; Horibe, Hideki; Muramatsu, Masaaki; Sawabe, Motoji; Fujiwara, Yoshinori; Taniguchi, Yu; Obuchi, Shuichi; Kawai, Hisashi; Shinkai, Shoji; Mori, Seijiro; Arai, Tomio; Tanaka, Masashi

2017-01-01

We performed an exome-wide association study (EWAS) to identify genetic variants - in particular, low-frequency or rare variants with a moderate to large effect size - that confer susceptibility to aortic aneurysm with 8,782 Japanese subjects (456 patients with aortic aneurysm, 8,326 control individuals) and with the use of Illumina HumanExome-12 DNA Analysis BeadChip or Infinium Exome-24 BeadChip arrays. The correlation of allele frequencies for 41,432 single nucleotide polymorphisms (SNPs) that passed quality control to aortic aneurysm was examined with Fisher's exact test. Based on Bonferroni's correction, a P-value of <1.21×10−6 was considered statistically significant. The EWAS revealed 59 SNPs that were significantly associated with aortic aneurysm. None of these SNPs was significantly (P<2.12×10−4) associated with aortic aneurysm by multivariable logistic regression analysis with adjustment for age, gender and hypertension, although 8 SNPs were related (P<0.05) to this condition. Examination of the correlation of these latter 8 SNPs to true or dissecting aortic aneurysm separately showed that rs1465567 [T/C (W229R)] of the EGF-like, fibronectin type III, and laminin G domains gene (EGFLAM) (dominant model; P=0.0014; odds ratio, 1.63) was significantly (P<0.0016) associated with true aortic aneurysm. We next performed EWASs for true or dissecting aortic aneurysm separately and found that 45 and 19 SNPs were significantly associated with these conditions, respectively. Multivariable logistic regression analysis with adjustment for covariates revealed that rs113710653 [C/T (E231K)] of the spermatogenesis- and centriole associated 1-like gene (SPATC1L) (dominant model; P=0.0002; odds ratio, 5.32) and rs143881017 [C/T (R140H)] of the ribonuclease A family member 13 gene (RNASE13) (dominant model; P=0.0006; odds ratio, 5.77) were significantly (P<2.78×10−4 or P<6.58×10−4, respectively) associated with true or dissecting aortic aneurysm, respectively. EGFLAM and SPATC1L may thus be susceptibility loci for true aortic aneurysm and RNASE13 may be such a locus for dissecting aneurysm in Japanese individuals. PMID:28339009

Three-year audit and cost assessment of open abdominal aortic aneurysm repair in a district general hospital.

PubMed

El Kafsi, J; Wake, J; Lintott, P; Northeast, A; McLaren, A

2009-11-01

The aims of this study were to audit the outcome of elective open abdominal aortic aneurysm (AAA) repair in a district general hospital, as well as investigate the true costs for this procedure in relation to the national tariff. A database is maintained on AAA surgery in the trust. Data were supplemented by drawing information from blood bank and clinical notes. Patients with symptomatic or emergency aneurysms were excluded. Data from January 2005 to December 2007 were obtained on demographics, morbidity, 30-day mortality and blood usage. Costs were obtained from the trust finance department. Between January 2005 and December 2007, 79 elective AAA procedures were undertaken. Median age was 75 years (range, 52-85 years), median aneurysm size was 63 mm (range, 42-105 mm) and median ITU stay was 3 days (range, 1-41 days). Major morbidity rate was 20.3% (16 of 79 patients) and 30-day mortality overall was 5.1% (4 of 79 patients). Average cost per case was pound15,012.91 (range, pound4,040.03- pound82,158.00), when National Tariff is pound6,722.00 ( pound5,649.00 x local Market Forces Factor of 1.19). Loss per case for our trust was pound8,290.91 with a total annual loss of pound218,299.56. Morbidity and mortality in this district general hospital compare well with national studies; however, the total cost is far in excess of the national tariff.

Colorectal cancer associated with abdominal aortic aneurysm: results of EVAR followed by colectomy.

PubMed

Illuminati, Giulio; Ceccanei, Gianluca; Pacilè, Maria A; Pizzardi, Giulia; Palumbo, Piergaspare; Vietri, Francesco

2013-01-01

The association of colorectal cancer and abdominal aortic aneurysm (AAA) is infrequent but poses special problems of priority of treatment under elective circumstances. The purpose of this study was to retrospectively evaluate the outcome of 16 consecutive patients undergoing endovascular aneurysm repair (EVAR) followed by colectomy. Operative mortality was nil. Operative morbidity included two transient rise of serum creatinine level and one extraperitoneal anastomotic leakage which evolved favourably with conservative treatment. EVAR allowed a very short delay of treatment of colorectal cancer after aneurysm repair, minimizing operative complications.

Morbidity and mortality associated with creation of elastase-induced saccular aneurysms in a rabbit model

PubMed Central

Lewis, Debra A; Ding, Yong Hong; Dai, Daying; Kadirvel, Ramanathan; Danielson, Mark A; Cloft, Harry J; Kallmes, David F

2008-01-01

Background and Purpose Elastase-induced aneurysms in rabbits have been proposed as a useful preclinical tool for device development. The object of this study is to report rates of morbidity and mortality associated with creation and embolization of the elastase-induced rabbit aneurysm, and to assess the impact of operator experience on these rates. Methods Elastase-induced model aneurysms were created in New Zealand White rabbits (n=700). One neuroradiologist/investigator, naïve to the aneurysm creation procedure at the outset of the experiments, performed all surgeries. All morbidity and deaths related to aneurysm creation (n=700) and embolization procedures (n=529) were categorized into acute and chronic deaths. Data were analyzed with single regression analysis and ANOVA. To assess the impact of increasing operator experience, the number of animals was broken into 50 animal increments. Results There were 121 (17%) deaths among 700 subjects. Among 700 aneurysm creation procedures, 59 deaths (8.4%) were noted. Among 529 aneurysm embolization procedures, 43 deaths (8.1%) were noted. Nineteen additional deaths (2.7% of 700 subjects) were unrelated to procedures. Simple regression indicated mortality associated with procedures diminished with increasing operator experience (R2=0.38; p=0.0180) and that for each 50 rabbit increment mortality is reduced on average by 0.6 percent. Conclusions Mortality rates of approximately 8% are associated with both experimental aneurysm creation and with embolization in the rabbit, elastase-induced aneurysm model. Increasing operator experience is inversely correlated with mortality and the age of the rabbit is positively associated with morbidity. PMID:19001536

Radio aneurysm coils for noninvasive detection of cerebral embolization failures: a preliminary study.

PubMed

Mohammadi, Abdolreza Rashidi; Chen, Keqin; Ali, Mohamed Sultan Mohamed; Takahata, Kenichi

2011-12-15

The rupture of a cerebral aneurysm is the most common cause of subarachnoid hemorrhage. Endovascular embolization of the aneurysms by implantation of Guglielmi detachable coils (GDC) has become a major treatment approach in the prevention of a rupture. Implantation of the coils induces formation of tissues over the coils, embolizing the aneurysm. However, blood entry into the coiled aneurysm often occurs due to failures in the embolization process. Current diagnostic methods used for aneurysms, such as X-ray angiography and computer tomography, are ineffective for continuous monitoring of the disease and require extremely expensive equipment. Here we present a novel technique for wireless monitoring of cerebral aneurysms using implanted embolization coils as radiofrequency resonant sensors that detect the blood entry. The experiments show that commonly used embolization coils could be utilized as electrical inductors or antennas. As the blood flows into a coil-implanted aneurysm, parasitic capacitance of the coil is modified because of the difference in permittivity between the blood and the tissues grown around the coil, resulting in a change in the coil's resonant frequency. The resonances of platinum GDC-like coils embedded in aneurysm models are detected to show average responses of 224-819 MHz/ml to saline injected into the models. This preliminary demonstration indicates a new possibility in the use of implanted GDC as a wireless sensor for embolization failures, the first step toward realizing long-term, noninvasive, and cost-effective remote monitoring of cerebral aneurysms treated with coil embolization. Copyright © 2011 Elsevier B.V. All rights reserved.

Treatment of Recurrent Intracranial Aneurysms After Clipping: A Report of 23 Cases and a Review of the Literature.

PubMed

Hokari, Masaaki; Kazumara, Ken; Nakayama, Naoki; Ushikoshi, Satoshi; Sugiyama, Taku; Asaoka, Katsunori; Uchida, Kazuki; Shimbo, Daisuke; Itamoto, Koji; Yokoyama, Yuka; Isobe, Masanori; Imai, Tetsuaki; Osanai, Toshiya; Houkin, Kiyohiro

2016-08-01

There are no established treatment strategies for aneurysms that recur after clipping. In this study, we present cases of patients who experienced recurrent aneurysms after clipping and subsequently underwent surgical intervention. Between 2004 and 2015, we surgically treated 23 aneurysms that recurred at a previously clipped site. Patient characteristics and clinical history were retrospectively reviewed. Patients included 19 women and 4 men 45-81 years old. Aneurysms recurred 3-31 years (mean, 15.4 years) after the initial operation. For 18 cases, the first clinical presentation was a subarachnoid hemorrhage; aneurysms were incidentally diagnosed in 5 patients. Aneurysm locations were as follows: 9 on the internal carotid artery; 4 on the middle cerebral artery; 7 on the anterior communicating artery; 2 on the distal anterior cerebral artery; and 1 on the basilar artery. The reasons for retreatment included subarachnoid hemorrhage (n = 9) and aneurysm regrowth detected on follow-up examinations (n = 14). Endovascular treatment was performed in 10 cases, and direct surgery was performed in 13 cases (clipping in 8, clipping or trapping with bypass in 5). Various complex vascular reconstructions, including high-flow bypass and intracranial-intracranial in situ bypass, were performed for recurrent aneurysms. In our experience, coil embolization is a safe and effective procedure for treating recurrent aneurysms. When cases are unsuitable for coil embolization, surgical treatment often requires neurosurgeons not only to overcome the general technical difficulty of reoperative clipping but also to perform challenging vascular reconstruction. Copyright © 2016. Published by Elsevier Inc.

Endovascular Treatment of Cerebral Aneurysms in Relation to Their Parent Artery Wall: A Single Center Study

PubMed Central

Mitsos, A.P.; Giannakopoulou, M.D.; Kaklamanos, I.G.; Kapritsou, M.; Konstantinou, M.I.; Fotis, T.; Mamoura, K.V.; Mariolis-Sapsakos, T.; Ntountas, I.T.; Konstantinou, E.A.

2013-01-01

We report our two-year experience in the endovascular treatment of brain aneurysms in relation to their parent artery wall. We prospectively recorded patients with intracranial aneurysms (107 ruptured - 38 unruptured) treated with coiling during a two-year period: 145 patients, 94 females and 51 males - mean age 56 years. The aneurysms were divided into side-wall (A) and bifurcation (B) groups. A total occlusion rate was noted in post-embolization angiograms in 101 aneurysms (70%) with a morbidity of 4%. No angiographic recurrence arose in the six-month follow-up. The two groups had a similar total occlusion rate (68.31% and 71.8% respectively), while the complication rate was 3% in group A and 4.7% in group B. Significant differences between the two groups were noted in the number of assisted coiling cases: 28 out of 60 cases (46.7%) in group A - 14 out of 85 cases (16.5%) in group B. Further statistical analysis showed strong dependencies for the type of endovascular procedure between the ruptured and unruptured aneurysms in both groups (p 0.000<0.05), but no dependencies between the aneurysm occlusion rate and the ruptured or non-ruptured aneurysms, or between the occlusion rate and the type of endovascular procedure (p 0.552 >0.05 and 0.071 >0.05 respectively). In conclusion, the anatomic relation of the aneurysm sac with the wall of the parent artery is important, as significant differences in endovascular practice, devices and techniques were noted between side-wall and bifurcation aneurysms. PMID:23859171

Nickel-related adverse reactions in the treatment of cerebral aneurysms: a literature review.

PubMed

Tsang, Anderson Chun On; Nicholson, Patrick; Pereira, Vitor Mendes

2018-04-20

Nickel is the most common metal allergen and predominantly affects women. It is also the ubiquitous component in the alloys used to manufacture intracranial devices for aneurysm treatments, including aneurysm clips, self-expanding stents, flow-diverting stents and endosaccular occlusion devices. Adverse events related to nickel-allergy after deployment of such devices are uncommon but can be severe, resulting in dilemmas in the choice of treatment strategies and devices in managing nickel-sensitive patients with intracranial aneurysms. A literature search in accordance with the PRISMA guidelines was performed to identify studies reporting on nickel-related adverse events in cerebral aneurysm treatment. The material of the culprit devices, clinical presentation, histological feature and treatment were reviewed. The clinical consideration and management options for nickel allergy patients were discussed. Nickel is a major component of the cobalt-alloy used in aneurysm clips, and of nitinol which is commonly used in flow-diverters and intracranial stents. There were 9 papers reporting 10 unique cases of nickel-related adverse events after aneurysm treatment. Half of the cases occurred after aneurysm clipping and the remaining 5 was attributed to endovascular devices. Two presented with dermatological and 8 with neurological manifestations including cerebral edema and cerebritis. Neurological complication related to nickel in cerebral aneurysm treatments is rare but remains a concern due to the high prevalence of nickel allergy in the population. Surgeons and interventionists should consider the metal-allergy history and its potential clinical significance in managing nickel-allergic patients with aneurysms. Copyright © 2018 Elsevier Inc. All rights reserved.

Morphological parameters associated with ruptured posterior communicating aneurysms.

PubMed

Ho, Allen; Lin, Ning; Charoenvimolphan, Nareerat; Stanley, Mary; Frerichs, Kai U; Day, Arthur L; Du, Rose

2014-01-01

The rupture risk of unruptured intracranial aneurysms is known to be dependent on the size of the aneurysm. However, the association of morphological characteristics with ruptured aneurysms has not been established in a systematic and location specific manner for the most common aneurysm locations. We evaluated posterior communicating artery (PCoA) aneurysms for morphological parameters associated with aneurysm rupture in that location. CT angiograms were evaluated to generate 3-D models of the aneurysms and surrounding vasculature. Univariate and multivariate analyses were performed to evaluate morphological parameters including aneurysm volume, aspect ratio, size ratio, distance to ICA bifurcation, aneurysm angle, vessel angles, flow angles, and vessel-to-vessel angles. From 2005-2012, 148 PCoA aneurysms were treated in a single institution. Preoperative CTAs from 63 patients (40 ruptured, 23 unruptured) were available and analyzed. Multivariate logistic regression revealed that smaller volume (p = 0.011), larger aneurysm neck diameter (0.048), and shorter ICA bifurcation to aneurysm distance (p = 0.005) were the most strongly associated with aneurysm rupture after adjusting for all other clinical and morphological variables. Multivariate subgroup analysis for patients with visualized PCoA demonstrated that larger neck diameter (p = 0.018) and shorter ICA bifurcation to aneurysm distance (p = 0.011) were significantly associated with rupture. Intracerebral hemorrhage was associated with smaller volume, larger maximum height, and smaller aneurysm angle, in addition to lateral projection, male sex, and lack of hypertension. We found that shorter ICA bifurcation to aneurysm distance is significantly associated with PCoA aneurysm rupture. This is a new physically intuitive parameter that can be measured easily and therefore be readily applied in clinical practice to aid in the evaluation of patients with PCoA aneurysms.

Morphological Parameters Associated with Ruptured Posterior Communicating Aneurysms

PubMed Central

Ho, Allen; Lin, Ning; Charoenvimolphan, Nareerat; Stanley, Mary; Frerichs, Kai U.; Day, Arthur L.; Du, Rose

2014-01-01

The rupture risk of unruptured intracranial aneurysms is known to be dependent on the size of the aneurysm. However, the association of morphological characteristics with ruptured aneurysms has not been established in a systematic and location specific manner for the most common aneurysm locations. We evaluated posterior communicating artery (PCoA) aneurysms for morphological parameters associated with aneurysm rupture in that location. CT angiograms were evaluated to generate 3-D models of the aneurysms and surrounding vasculature. Univariate and multivariate analyses were performed to evaluate morphological parameters including aneurysm volume, aspect ratio, size ratio, distance to ICA bifurcation, aneurysm angle, vessel angles, flow angles, and vessel-to-vessel angles. From 2005–2012, 148 PCoA aneurysms were treated in a single institution. Preoperative CTAs from 63 patients (40 ruptured, 23 unruptured) were available and analyzed. Multivariate logistic regression revealed that smaller volume (p = 0.011), larger aneurysm neck diameter (0.048), and shorter ICA bifurcation to aneurysm distance (p = 0.005) were the most strongly associated with aneurysm rupture after adjusting for all other clinical and morphological variables. Multivariate subgroup analysis for patients with visualized PCoA demonstrated that larger neck diameter (p = 0.018) and shorter ICA bifurcation to aneurysm distance (p = 0.011) were significantly associated with rupture. Intracerebral hemorrhage was associated with smaller volume, larger maximum height, and smaller aneurysm angle, in addition to lateral projection, male sex, and lack of hypertension. We found that shorter ICA bifurcation to aneurysm distance is significantly associated with PCoA aneurysm rupture. This is a new physically intuitive parameter that can be measured easily and therefore be readily applied in clinical practice to aid in the evaluation of patients with PCoA aneurysms. PMID:24733151

Nanoparticles Effectively Target Rapamycin Delivery to Sites of Experimental Aortic Aneurysm in Rats.

PubMed

Shirasu, Takuro; Koyama, Hiroyuki; Miura, Yutaka; Hoshina, Katsuyuki; Kataoka, Kazunori; Watanabe, Toshiaki

2016-01-01

Several drugs targeting the pathogenesis of aortic aneurysm have shown efficacy in model systems but not in clinical trials, potentially owing to the lack of targeted drug delivery. Here, we designed a novel drug delivery system using nanoparticles to target the disrupted aortic aneurysm micro-structure. We generated poly(ethylene glycol)-shelled nanoparticles incorporating rapamycin that exhibited uniform diameter and long-term stability. When injected intravenously into a rat model in which abdominal aortic aneurysm (AAA) had been induced by infusing elastase, labeled rapamycin nanoparticles specifically accumulated in the AAA. Microscopic analysis revealed that rapamycin nanoparticles were mainly distributed in the media and adventitia where the wall structures were damaged. Co-localization of rapamycin nanoparticles with macrophages was also noted. Rapamycin nanoparticles injected during the process of AAA formation evinced significant suppression of AAA formation and mural inflammation at 7 days after elastase infusion, as compared with rapamycin treatment alone. Correspondingly, the activities of matrix metalloproteinases and the expression of inflammatory cytokines were significantly suppressed by rapamycin nanoparticle treatment. Our findings suggest that the nanoparticle-based delivery system achieves specific delivery of rapamycin to the rat AAA and might contribute to establishing a drug therapy approach targeting aortic aneurysm.

Nanoparticles Effectively Target Rapamycin Delivery to Sites of Experimental Aortic Aneurysm in Rats

PubMed Central

Shirasu, Takuro; Koyama, Hiroyuki; Miura, Yutaka; Hoshina, Katsuyuki; Kataoka, Kazunori; Watanabe, Toshiaki

2016-01-01

Several drugs targeting the pathogenesis of aortic aneurysm have shown efficacy in model systems but not in clinical trials, potentially owing to the lack of targeted drug delivery. Here, we designed a novel drug delivery system using nanoparticles to target the disrupted aortic aneurysm micro-structure. We generated poly(ethylene glycol)-shelled nanoparticles incorporating rapamycin that exhibited uniform diameter and long-term stability. When injected intravenously into a rat model in which abdominal aortic aneurysm (AAA) had been induced by infusing elastase, labeled rapamycin nanoparticles specifically accumulated in the AAA. Microscopic analysis revealed that rapamycin nanoparticles were mainly distributed in the media and adventitia where the wall structures were damaged. Co-localization of rapamycin nanoparticles with macrophages was also noted. Rapamycin nanoparticles injected during the process of AAA formation evinced significant suppression of AAA formation and mural inflammation at 7 days after elastase infusion, as compared with rapamycin treatment alone. Correspondingly, the activities of matrix metalloproteinases and the expression of inflammatory cytokines were significantly suppressed by rapamycin nanoparticle treatment. Our findings suggest that the nanoparticle-based delivery system achieves specific delivery of rapamycin to the rat AAA and might contribute to establishing a drug therapy approach targeting aortic aneurysm. PMID:27336852

Turbulence significantly increases pressure and fluid shear stress in an aortic aneurysm model under resting and exercise flow conditions.

PubMed

Khanafer, Khalil M; Bull, Joseph L; Upchurch, Gilbert R; Berguer, Ramon

2007-01-01

The numerical models of abdominal aortic aneurysm (AAA) in use do not take into account the non-Newtonian behavior of blood and the development of local turbulence. This study examines the influence of pulsatile, turbulent, non-Newtonian flow on fluid shear stresses and pressure changes under rest and exercise conditions. We numerically analyzed pulsatile turbulent flow, using simulated physiological rest and exercise waveforms, in axisymmetric-rigid aortic aneurysm models (AAMs). Discretization of governing equations was achieved using a finite element scheme. Maximum turbulence-induced shear stress was found at the distal end of an AAM. In large AAMs (dilated to undilated diameter ratio = 3.33) at peak systolic flow velocity, fluid shear stress during exercise is 70.4% higher than at rest. Our study provides a numerical, noninvasive method for obtaining detailed data on the forces generated by pulsatile turbulent flow in AAAs that are difficult to study in humans and in physical models. Our data suggest that increased flow turbulence results in increased shear stress in aneurysms. While pressure readings are fairly uniform along the length of an aneurysm, the kinetic energy generated by turbulence impacting on the wall of the distal half of the aneurysm increases fluid and wall shear stress at this site. If the increased fluid shear stress results in further dilation and hence further turbulence, wall stress may be a mechanism for aneurysmal growth and eventual rupture.

An examination of aneurysm rerupture rates with epsilon aminocaproic acid.

PubMed

Schuette, Albert J; Hui, Ferdinand K; Obuchowski, Nancy A; Walkup, Raymond R; Cawley, Charles M; Barrow, Daniel L; Samuels, Owen B

2013-08-01

Epsilon aminocaproic acid (EACA) has been used in the past to prevent cerebral aneurysm rerupture. Recent studies have indicated that short-term treatment with EACA can lower rebleeding rates without significantly increasing ischemic or thrombotic complications or permanent shunt rates. The goal of this study is to determine the efficacy of EACA in the prevention of aneurysm rerupture at a high volume subarachnoid hemorrhage center. We conducted a retrospective study of 355 consecutive subarachnoid hemorrhage patients over a 2-year period under our current protocol for EACA use. Patients were divided by presentation time to our institution and whether the patient received EACA. The primary endpoints of the study were rebleeding rates, ischemic complications, thrombotic complications, vasospasm, shunt rates, and outcomes. Rerupture rates were reduced by half in the entire pool of patients on EACA after controlling for Hunt and Hess Scores and Fisher Scores. In patients who received early aneurysm treatment, this effect persisted but was non-statistically significant due to the small numbers of reruptures. In addition, there was no evidence to suggest that EACA increased ischemic or thrombotic complications, vasospasm, or VPS rates. In patients presenting earlier than 24 h to our institution, there was a non-significant trend toward worse outcomes after EACA use. This trend was reversed in patients arriving after 24 h. There is evidence to suggest that EACA is protective from aneurysm rerupture without significant ischemic or thrombotic complications when used for less than 72 h. However, if the aneurysm is treated, this effect is modest indicating that early aneurysm treatment remains the gold standard for rerupture prevention.

Endovascular repair of descending thoracic aortic aneurysm: an evidence-based analysis.

PubMed

2005-01-01

To conduct an assessment on endovascular repair of descending thoracic aortic aneurysm (TAA). Aneurysm is the most common condition of the thoracic aorta requiring surgery. Aortic aneurysm is defined as a localized dilatation of the aorta. Most aneurysms of the thoracic aorta are asymptomatic and incidentally discovered. However, TAA tends to enlarge progressively and compress surrounding structures causing symptoms such as chest or back pain, dysphagia (difficulty swallowing), dyspnea (shortness of breath), cough, stridor (a harsh, high-pitched breath sound), and hoarseness. Significant aortic regurgitation causes symptoms of congestive heart failure. Embolization of the thrombus to the distal arterial circulation may occur and cause related symptoms. The aneurysm may eventually rupture and create a life-threatening condition. The overall incidence rate of TAA is about 10 per 100,000 person-years. The descending aorta is involved in about 30% to 40% of these cases. The prognosis of large untreated TAAs is poor, with a 3-year survival rate as low as 25%. Intervention is strongly recommended for any symptomatic TAA or any TAA that exceeds twice the diameter of a normal aorta or is 6 cm or larger. Open surgical treatment of TAA involves left thoracotomy and aortic graft replacement. Surgical treatment has been found to improve survival when compared with medical therapy. However, despite dramatic advances in surgical techniques for performing such complex operations, operative mortality from centres of excellence are between 8% and 20% for elective cases, and up to 50% in patients requiring emergency operations. In addition, survivors of open surgical repair of TAAs may suffer from severe complications. Postoperative or postprocedural complications of descending TAA repair include paraplegia, myocardial infarction, stroke, respiratory failure, renal failure, and intestinal ischemia. Endovascular aortic aneurysm repair (EVAR) using a stent graft, a procedure called endovascular stent-graft (ESG) placement, is a new alternative to the traditional surgical approach. It is less invasive, and initial results from several studies suggest that it may reduce mortality and morbidity associated with the repair of descending TAAs. The goal in endovascular repair is to exclude the aneurysm from the systemic circulation and prevent it from rupturing, which is life-threatening. The endovascular placement of a stent graft eliminates the systemic pressure acting on the weakened wall of the aneurysm that may lead to the rupture. However, ESG placement has some specific complications, including endovascular leak (endoleak), graft migration, stent fracture, and mechanical damage to the access artery and aortic wall. The Talent stent graft (manufactured by Medtronic Inc., Minneapolis, MN) is licensed in Canada for the treatment of patients with TAA (Class 4; licence 36552). The design of this device has evolved since its clinical introduction. The current version has a more flexible delivery catheter than did the original system. The prosthesis is composed of nitinol stents between thin layers of polyester graft material. Each stent is secured with oversewn sutures to prevent migration. Objectives To compare the effectiveness and cost-effectiveness of ESG placement in the treatment of TAAs with a conventional surgical approachTo summarize the safety profile and effectiveness of ESG placement in the treatment of descending TAAsMeasures of Effectiveness Primary Outcome Mortality rates (30-day and longer term)Secondary Outcomes Technical success rate of introducing a stent graft and exclusion of the aneurysm sac from systemic circulationRate of reintervention (through surgical or endovascular approach)Measures of Safety Complications were categorized into 2 classes: Those specific to the ESG procedure, including rates of aneurysm rupture, endoleak, graft migration, stent fracture, and kinking; andThose due to the intervention, either surgical or endovascular. These include paraplegia, stroke, cardiovascular events, respiratory failure, real insufficiency, and intestinal ischemia.Inclusion Criteria Studies comparing the clinical outcomes of ESG treatment with surgical approachesStudies reporting on the safety and effectiveness of the ESG procedure for the treatment of descending TAAsExclusion Criteria Studies investigating the clinical effectiveness of ESG placement for other conditions such as aortic dissection, aortic ulcer, and traumatic injuries of the thoracic aortaStudies investigating the aneurysms of the ascending and the arch of the aortaStudies using custom-made graftsLiterature Search The Medical Advisory Secretariat searched The International Network of Agencies for Health Technology Assessment and the Cochrane Database of Systematic Reviews for health technology assessments. It also searched MEDLINE, EMBASE, Medline In-Process & Other Non-Indexed Citations, and Cochrane CENTRAL from January 1, 2000 to July 11, 2005 for studies on ESG procedures. The search was limited to English-language articles and human studies. One health technology assessment from the United Kingdom was identified. This systematic review included all pathologies of the thoracic aorta; therefore, it did not match the inclusion criteria. The search yielded 435 citations; of these, 9 studies met inclusion criteria. Mortality The results of a comparative study found that in-hospital mortality was not significantly different between ESG placement and surgery patients (2 [4.8%] for ESG vs. 6 [11.3%] for surgery).Pooled data from case series with a mean follow-up ranging from 12 to 38 months showed a 30-day mortality and late mortality rate of 3.9% and 5.5%, respectively. These rates are lower than are those reported in the literature for surgical repair of TAA.Case series showed that the most common cause of early death in patients undergoing endovascular repair is aortic rupture, and the most common causes of late death are cardiac events and aortoesophageal or aortobronchial fistula.Technical Success Rate Technical success rates reported by case series are 55% to 100% (100% and 94.4% in 2 studies with all elective cases, 89% in a study with 5% emergent cases, and 55% in a study with 42% emergent cases).Surgical Reintervention In the comparative study, 3 (7.1%) patients in the ESG group and 14 (26.5%) patients in the surgery group required surgical reintervention. In the ESG group, the reasons for surgical intervention were postoperative bleeding at the access site, paraplegia, and type 1 endoleak. In the surgical group, the reasons for surgery were duodenal perforation, persistent thoracic duct leakage, false aneurysm, and 11 cases of postoperative bleeding.Pooled data from case series show that 9 (2.6%) patients required surgical intervention. The reasons for surgical intervention were endoleak (3 cases), aneurysm enlargement and suspected infection (1 case), aortic dissection (1 case), pseudoaneurysm of common femoral artery (1 case), evacuation of hematoma (1 case), graft migration (1 case), and injury to the access site (1 case).Endovascular Revision In the comparative study, 3 (7.1%) patients required endovascular revision due to persistent endoleak.Pooled data from case series show that 19 (5.3%) patients required endovascular revision due to persistent endoleak.Graft Migration Two case series reported graft migration. In one study, 3 proximal and 4 component migrations were noted at 2-year follow-up (total of 5%). Another study reported 1 (3.7%) case of graft migration. Overall, the incidence of graft migration was 2.6%.Aortic Rupture In the comparative study, aortic rupture due to bare stent occurred in 1 case (2%). The pooled incidence of aortic rupture or dissection reported by case series was 1.4%.Postprocedural Complications In the comparative study, there were no statistically significant differences between the ESG and surgery groups in postprocedural complications, except for pneumonia. The rate of pneumonia was 9% for those who received an ESG and 28% for those who had surgery (P = .02). There were no cases of paraplegia in either group. The rate of other complications for ESG and surgery including stroke, cardiac, respiratory, and intestinal ischemia were all 5.1% for ESG placement and 10% for surgery. The rate for mild renal failure was 16% in the ESG group and 30% in the surgery group. The rate for severe renal failure was 11% for ESG placement and 10% for surgery.POOLED DATA FROM CASE SERIES SHOW THE FOLLOWING POSTPROCEDURAL COMPLICATION RATES IN THE ESG PLACEMENT GROUP: paraplegia (2.2%), stroke (3.9%), cardiac (2.9%), respiratory (8.7%), renal failure (2.8%), and intestinal ischemia (1%).Time-Related Outcomes The results of the comparative study show statistically significant differences between the ESG and surgery group for mean operative time (ESG, 2.7 hours; surgery, 5 hours), mean duration of intensive care unit stay (ESG, 11 days; surgery, 14 days), and mean length of hospital stay (ESG, 10 days; surgery, 30 days).The mean duration of intensive care unit stay and hospital stay derived from case series is 1.6 and 7.8 days, respectively. ONTARIO-BASED ECONOMIC ANALYSIS: In Ontario, the annual treatment figures for fiscal year 2004 include 17 cases of descending TAA repair procedures (source: Provincial Health Planning Database). Fourteen of these have been identified as "not ruptured" with a mean hospital length of stay of 9.23 days, and 3 cases have been identified as "ruptured," with a mean hospital length of stay of 28 days. However, because one Canadian Classification of Health Interventions code was used for both procedures, it is not possible to determine how many were repaired with an EVAR procedure or with an open surgical procedure. (ABSTRACT TRUNCATED)

Endovascular stent-graft repair of failed endovascular abdominal aortic aneurysm repair.

PubMed

Baril, Donald T; Silverberg, Daniel; Ellozy, Sharif H; Carroccio, Alfio; Jacobs, Tikva S; Sachdev, Ulka; Teodorescu, Victoria J; Lookstein, Robert A; Marin, Michael L

2008-01-01

Despite high initial technical success, the long-term durability of endovascular abdominal aortic aneurysm repair (EVAR) continues to be a concern. Following EVAR, patients can experience endoleaks, device migration, device fractures, or aneurysm growth that may require intervention. The purpose of this study was to review all patients treated with secondary endovascular devices at our institution for failed EVAR procedures. Over an 8-year period, 988 patients underwent EVAR, of whom 42 (4.3%) required secondary interventions involving placement of additional endovascular devices. Data regarding patient characteristics, aneurysm size, initial device type, time until failure, failure etiology, secondary interventions, and outcomes were reviewed. The mean time from initial operation until second operation was 34.1 months. Failures included type I endoleaks in 38 patients (90.5%), type III endoleaks in two patients (4.8%), and enlarging aneurysms without definite endoleaks in two patients (4.8%). The overall technical success rate for secondary repair was 92.9% (39/42). Perioperative complications occurred in nine patients (21.4%), including wound complications (n = 6), cerebrovascular accident (CVA) (n = 1), foot drop (n = 1), and death (n = 1). Mean follow-up following secondary repair was 16.4 months (range 1-50). Eighty-six percent of patients treated with aortouni-iliac devices had successful repairs compared to 45% of patients treated with proximal cuffs. Ten patients (23.8%) had persistent or recurrent type I or type III endoleaks following revision. Of these, four had tertiary interventions, including two patients who had additional devices placed. Failures following EVAR occur in a small but significant number of patients. When anatomically possible, endovascular revision offers a safe means of treating these failures. Aortouni-iliac devices appear to offer a more durable repair than the proximal cuff for treatment of proximal type I endoleaks. Midterm results indicate that these patients may require additional procedures but have a low rate of aneurysm-related mortality. Longer-term follow-up is necessary to determine the durability of these endovascular revisions.

Trends in treatment of ruptured abdominal aortic aneurysm: impact of endovascular repair and implications for future care.

PubMed

Park, Brian D; Azefor, Nchang; Huang, Chun-Chih; Ricotta, John J

2013-04-01

Our aim was to determine national trends in treatment of ruptured abdominal aortic aneurysm (RAAA), with specific emphasis on open surgical repair (OSR) and endovascular aneurysm repair (EVAR) and its impact on mortality and complications. Data from the Nationwide Inpatient Sample (NIS) from 2005 to 2009 were queried to identify patients older than 59 years with RAAA. Three groups were studied: nonoperative (NO), EVAR, and OSR. Chi-square analysis was used to determine the relationship between treatment type and patient demographics, clinical characteristics, and hospital type. The impact of EVAR compared with OSR on mortality and overall complications was examined using logistic regression analysis. We identified 21,206 patients with RAAA from 2005 to 2009, of which 16,558 (78.1%) underwent operative repair and 21.8% received no operative treatment. In the operative group, 12,761 (77.1%) underwent OSR and 3,796 (22.9%) underwent EVAR. Endovascular aneurysm repair was more common in teaching hospitals (29.1% vs 15.2%, p < .0001) and in urban versus rural settings. Nonoperative approach was twice as common in rural versus urban hospitals. Reduced mortality was seen in patients transferred from another institutions (31.2% vs 39.4%, p = 0.014). Logistic regression analysis demonstrated a benefit of EVAR on both complication rate (OR = 0.492; CI, 0.380-0.636) and mortality (OR=0.535; CI, 0.395-0.724). Endovascular aneurysm repair use is increasing for RAAA and is more common in urban teaching hospitals while NO therapy is more common in rural hospitals. Endovascular aneurysm repair is associated with reduced mortality and complications across all age groups. Efforts to reduce mortality from RAAA should concentrate on reducing NO and OSR in patients who are suitable for EVAR. Copyright © 2013 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Comparison of standard- and low-tube voltage 320-detector row volume CT angiography in detection of intracranial aneurysms with digital subtraction angiography as gold standard.

PubMed

Sun, Gang; Ding, Juan; Lu, Yang; Li, Min; Li, Li; Li, Guo-ying; Zhang, Xu-ping

2012-03-01

The aim of this study was to prospectively assess the effect of low-tube voltage (80 kVp) 320-detector row volume computed tomographic (CT) angiography (L-VCTA) in the detection of intracranial aneurysms, with three-dimensional (3D) spin digital subtraction angiography (DSA) as the gold standard. Forty-eight patients with clinically suspected subarachnoid hemorrhages were divided into two groups. One group underwent L-VCTA and DSA, while the other group underwent conventional-tube voltage (120 kVp) volume CT angiography (C-VCTA) and DSA. Vascular enhancement, image quality, detection accuracy of aneurysms, and radiation dose were compared between the two groups. For objective image quality, the L-VCTA group had higher mean vessel attenuation, correlated with higher image noise and lower signal-to-noise ratio, than the C-VCTA group. For subjective image quality, there were no significant differences between the two groups regarding scores for arterial enhancement, depiction of small arterial detail, interference of venous structures, and overall image quality scores. The mean effective dose for the L-VCTA group was significantly lower than for the C-VCTA group (0.56 ± 0.25 vs 1.84 ± 0.002 mSv), with a reduction of radiation dose of 69.73%. With 3D DSA as the reference standard, the sensitivity, specificity, and accuracy in the L-VCTA and C-VCTA groups were 94.12%, 100%, 94.4% and 100%, 100%, and 100%, respectively. In both groups, there were significant correlations for maximum aneurysm diameter measurements between volume CT angiography and 3D DSA; no statistical difference in the mean maximum diameter of each aneurysm was measured between volume CT angiography and 3D DSA. L-VCTA is helpful in detecting intracranial aneurysms, with results similar to those of 3D DSA, but at a lower radiation dose than C-VCTA. Copyright © 2012 AUR. Published by Elsevier Inc. All rights reserved.

Efficacy of perfusion cooling of the epidural space and cerebrospinal fluid drainage during repair of extent I and II thoracoabdominal aneurysm.

PubMed

Tabayashi, K; Motoyoshi, N; Saiki, Y; Kokubo, H; Takahashi, G; Masuda, S; Shibuya, T; Akasaka, J; Oda, K; Kamata, M; Iguti, A

2008-12-01

The aim of this study was to evaluate spinal cord injury and mortality resulting from repair of extent I and II thoracoabdominal aneurysm. The authors compared patients operated under mild hypothermia with or without epidural perfusion cooling (EPC) and cerebrospinal fluid drainage (CSFD). From 1988 to 2007, 116 patients underwent replacement of the thoracoabdominal aorta; the procedure was performed in 38 patients with the aid of mild hypothermia alone (group A), and in 78 patients with the aid of EPC, mild hypothermia and CSFD (group B). Two catheters for epidural perfusion cooling were inserted in group B, in which one catheter was inserted into the epidural space to infuse chilled saline, and the other was inserted into the subdural space to drain the cerebrospinal fluid and to measure temperature and pressure. There were no significant differences in mean age, etiology of aortic disease, and aneurysm extent between the two groups. There were no significant differences in cardiopulmonary bypass time, the lowest nasopharyngeal temperature and operation time between the two study groups. The incidence of spinal cord injury in group A (16.2%) was significantly higher than in group B (3.8%, P=0.03). Hospital mortality in groups A and B was 10.5% and 2.6%, respectively (P=0.08). There was no significant difference in postoperative complications between the two study groups. The combination of EPC and CSFD was effective in lowering the incidence of postoperative spinal cord injury in the repair of extent I and II thoracoabdominal aortic aneurysm.

In vitro analysis of platelet function in acute aneurysmal subarachnoid haemorrhage.

PubMed

von der Brelie, Christian; Subai, Alexander; Limperger, Verena; Rohde, Veit; Dempfle, Astrid; Boström, Azize

2018-04-01

Platelet function might play an essential role in the pathogenesis of delayed cerebral ischemia (DCI) after aneurysmal subarachnoid haemorrhage (SAH). Thus, impaired platelet function and disturbed primary haemostasis induced by intake of acetylsalicylic acid (ASA) might influence the rate of DCI. Primary haemostasis and platelet function can be measured with in vitro diagnosis (platelet function analyser test, PFA 100). The aim of this study is to evaluate the rate of DCI, haemorrhagic complications and the neurological outcome. Two groups were compared (patients with regular platelet function versus patients with impaired platelet function). This is a retrospective observational study. An initial cohort of 787 patients with SAH has been treated from January 2005 to September 2012. Seventy-nine patients (10%) with aneurysmal SAH, a history of ASA medication and PFA testing within the first 24 h after aneurysm rupture have been included. The overall rate of DCI in the present study was 43%. In vitro platelet function testing showed pathological primary haemostasis in 69.6%. The DCI rate was higher in patients with regular tested primary haemostasis (p = 0.02, OR = 3.16, 95%CI = [1.19; 8.83]). However, outcome assessment by mGOS did not show a significant difference between the groups. Patients with impaired primary haemostasis did not display a higher rate of haemorrhagic complications. Impairment of primary haemostasis resulting from an impairment of platelet function at an early stage after SAH might lead to a lower rate of DCI. In vitro testing of platelet function might be useful to predict the occurrence of DCI in the course.

Trends in aortic aneurysm- and dissection-related mortality in the state of São Paulo, Brazil, 1985–2009: multiple-cause-of-death analysis

PubMed Central

2012-01-01

Background Aortic aneurysm and dissection are important causes of death in older people. Ruptured aneurysms show catastrophic fatality rates reaching near 80%. Few population-based mortality studies have been published in the world and none in Brazil. The objective of the present study was to use multiple-cause-of-death methodology in the analysis of mortality trends related to aortic aneurysm and dissection in the state of Sao Paulo, between 1985 and 2009. Methods We analyzed mortality data from the Sao Paulo State Data Analysis System, selecting all death certificates on which aortic aneurysm and dissection were listed as a cause-of-death. The variables sex, age, season of the year, and underlying, associated or total mentions of causes of death were studied using standardized mortality rates, proportions and historical trends. Statistical analyses were performed by chi-square goodness-of-fit and H Kruskal-Wallis tests, and variance analysis. The joinpoint regression model was used to evaluate changes in age-standardized rates trends. A p value less than 0.05 was regarded as significant. Results Over a 25-year period, there were 42,615 deaths related to aortic aneurysm and dissection, of which 36,088 (84.7%) were identified as underlying cause and 6,527 (15.3%) as an associated cause-of-death. Dissection and ruptured aneurysms were considered as an underlying cause of death in 93% of the deaths. For the entire period, a significant increased trend of age-standardized death rates was observed in men and women, while certain non-significant decreases occurred from 1996/2004 until 2009. Abdominal aortic aneurysms and aortic dissections prevailed among men and aortic dissections and aortic aneurysms of unspecified site among women. In 1985 and 2009 death rates ratios of men to women were respectively 2.86 and 2.19, corresponding to a difference decrease between rates of 23.4%. For aortic dissection, ruptured and non-ruptured aneurysms, the overall mean ages at death were, respectively, 63.2, 68.4 and 71.6 years; while, as the underlying cause, the main associated causes of death were as follows: hemorrhages (in 43.8%/40.5%/13.9%); hypertensive diseases (in 49.2%/22.43%/24.5%) and atherosclerosis (in 14.8%/25.5%/15.3%); and, as associated causes, their principal overall underlying causes of death were diseases of the circulatory (55.7%), and respiratory (13.8%) systems and neoplasms (7.8%). A significant seasonal variation, with highest frequency in winter, occurred in deaths identified as underlying cause for aortic dissection, ruptured and non-ruptured aneurysms. Conclusions This study introduces the methodology of multiple-causes-of-death to enhance epidemiologic knowledge of aortic aneurysm and dissection in São Paulo, Brazil. The results presented confer light to the importance of mortality statistics and the need for epidemiologic studies to understand unique trends in our own population. PMID:23046791

Treatment of Visceral Aneurysm Using Multilayer Stent: Two-Year Follow-Up Results in Five Consecutive Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balderi, Alberto, E-mail: balders@libero.it; Antonietti, Alberto, E-mail: antonietti.a@ospedale.cuneo.it; Pedrazzini, Fulvio, E-mail: pedrazzini.f@ospedale.cuneo.it

Purpose: The present study was performed to analyze the midterm results (five consecutive patients, 2-year follow-up) of the endovascular management of visceral artery aneurysms using the Cardiatis Multilayer Flow Modulator (CMFM) (Cardiatis, Isnes, Belgium), a self-expandable stent. Materials and Methods: From August 2009 to January 2011, we implanted five CMFMs in five patients (all men; mean age 73 years) to treat two common hepatic artery aneurysms, one celiac trunk aneurysm, one splenic artery aneurysm, and one superior mesenteric artery aneurysm (diameter 25-81 mm). The primary end point was technical success. The secondary end point was stent patency, absence of aneurysmmore » rupture or reperfusion, and shrinking of the sac at 6-, 12-, and 24-month follow-up using computed tomography angiography. Follow-up ranged from 24 to 48 months (mean 31.2). Results: Technical success was achieved in all patients. Complete exclusion of the aneurysm with sac shrinking was achieved in two patients. Two stents became occluded at 6- and 24-month follow-up, respectively; both patients were asymptomatic and were not retreated. One patient developed sac reperfusion due to incomplete aneurysm exclusion. Conclusion: Long-term results in a wider population are needed to validate the effectiveness of the CMFM.« less