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Sample records for carotid aneurysm hemodynamics

  1. 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.

  2. Effects of Variations of Flow and Heart Rate on Intra-Aneurysmal Hemodynamics in a Ruptured Internal Carotid Artery Aneurysm During Exercise

    PubMed Central

    Sarrami-Foroushani, Ali; Nasr Esfahany, Mohsen; Saligheh Rad, Hamidreza; Firouznia, Kavous; Shakiba, Madjid; Ghanaati, Hossein

    2016-01-01

    Background: Hemodynamics is thought to play an important role in the mechanisms responsible for initiation, growth, and rupture of intracranial aneurysms. Computational fluid dynamic (CFD) analysis is used to assess intra-aneurysmal hemodynamics. Objectives: This study aimed to investigate the effects of variations in heart rate and internal carotid artery (ICA) flow rate on intra-aneurysmal hemodynamics, in an ICA aneurysm, by using computational fluid dynamics. Patients and Methods: Computed tomography angiography (CTA) was performed in a 55 years old female case, with a saccular ICA aneurysm, to create a patient-specific geometrical anatomic model of the aneurysm. The intra-aneurysmal hemodynamic environments for three states with different flow and heart rates were analyzed using patient-specific image-based CFD modeling. Results: Results showed significant changes for the three simulated states. For a proportion of the states examined, results were counterintuitive. Systolic and time-averaged wall shear stress and pressure on the aneurysm wall showed a proportional evolution with the mainstream flow rate. Conclusion: Results reinforced the pivotal role of vascular geometry, with respect to hemodynamics, together with the importance of performing patient-specific CFD analyses, through which the effect of different blood flow conditions on the aneurysm hemodynamics could be evaluated. PMID:27110332

  3. Hemodynamics model of fluid-solid interaction in internal carotid artery aneurysms.

    PubMed

    Bai-Nan, Xu; Fu-Yu, Wang; Lei, Liu; Xiao-Jun, Zhang; Hai-Yue, Ju

    2011-01-01

    The objective of this study is to present a relatively simple method to reconstruct cerebral aneurysms as 3D numerical grids. The method accurately duplicates the geometry to provide computer simulations of the blood flow. Initial images were obtained by using CT angiography and 3D digital subtraction angiography in DICOM format. The image was processed by using MIMICS software, and the 3D fluid model (blood flow) and 3D solid model (wall) were generated. The subsequent output was exported to the ANSYS workbench software to generate the volumetric mesh for further hemodynamic study. The fluid model was defined and simulated in CFX software while the solid model was calculated in ANSYS software. The force data calculated firstly in the CFX software were transferred to the ANSYS software, and after receiving the force data, total mesh displacement data were calculated in the ANSYS software. Then, the mesh displacement data were transferred back to the CFX software. The data exchange was processed in workbench software. The results of simulation could be visualized in CFX-post. Two examples of grid reconstruction and blood flow simulation for patients with internal carotid artery aneurysms were presented. The wall shear stress, wall total pressure, and von Mises stress could be visualized. This method seems to be relatively simple and suitable for direct use by neurosurgeons or neuroradiologists, and maybe a practical tool for planning treatment and follow-up of patients after neurosurgical or endovascular interventions with 3D angiography.

  4. High-flow bypass and wrap-clipping for ruptured blood blister-like aneurysm of the internal carotid artery using intraoperative monitoring of cerebral hemodynamics

    PubMed Central

    Kubo, Yoshitaka; Koji, Takahiro; Yoshida, Kenji; Saito, Hideo; Ogawa, Akira; Ogasawara, Kuniaki

    2015-01-01

    Aneurysms at non-branching sites in the supraclinoid internal carotid artery (ICA) can be classified as “blood blister-like aneurysms” (BBAs), which have blood blister-like configurations and fragile walls. While surgical treatment for the BBA in the acute stage is recommended, the optimal surgical procedure remains controversial. In the study reported here, we describe the case of a 37-year-old woman with a ruptured BBA in the ophthalmic segment of the right ICA who underwent wrap-clipping with external carotid artery–internal carotid artery bypass by intraoperative estimation of the measurement of cortical cerebral blood flow (CoBF) using a thermal diffusion flow probe. Trapping of the ICA in the acute stage of subarachnoid hemorrhage may result in ischemic complications secondary to hemodynamic hypoperfusion or occlusion of the perforating artery, and/or delayed vasospasm, even with concomitant bypass surgery. We believe that it is important to perform scheduled external carotid artery–internal carotid artery bypass before trapping of the ICA in patients with a ruptured BBA in the acute stage of subarachnoid hemorrhage and to perform wrap-clipping rather than trapping. This would provide much more CoBF if a reduction of CoBF occurs after trapping occlusion of the ICA including a ruptured BBA according to intraoperative CoBF monitoring. As far as we are aware, the case reported here is the first report on high-flow bypass and wrap-clipping for a ruptured BBA of the ICA using intraoperative monitoring of cerebral hemodynamics. PMID:26082641

  5. Hemodynamic Intervention of Cerebral Aneurysms

    NASA Astrophysics Data System (ADS)

    Meng, Hui

    2005-11-01

    Cerebral aneurysm is a pathological vascular response to hemodynamic stimuli. Endovascular treatment of cerebral aneurysms essentially alters the blood flow to stop them from continued growth and eventual rupture. Compared to surgical clipping, endovascular methods are minimally invasive and hence rapidly gaining popularity. However, they are not always effective with risks of aneurysm regrowth and various complications. We aim at developing a Virtual Intervention (VI) platform that allows: patient-specific flow calculation and risk prediction as well as recommendation of tailored intervention based on quantitative analysis. This is a lofty goal requiring advancement in three areas of research: (1). Advancement of image-based CFD; (2) Understanding the biological/pathological responses of tissue to hemodynamic factors in the context of cerebral aneurysms; and (3) Capability of designing and testing patient-specific endovascular devices. We have established CFD methodologies based on anatomical geometry obtained from 3D angiographic or CT images. To study the effect of hemodynamics on aneurysm development, we have created a canine model of a vascular bifurcation anastomosis to provide the hemodynamic environment similar to those in CA. Vascular remodeling was studied using histology and compared against the flow fields obtained from CFD. It was found that an intimal pad, similar to those frequently seen clinically, developed at the flow impingement site, bordering with an area of `groove' characteristic of an early stage of aneurysm, where the micro environment exhibits an elevated wall shear stresses. To further address the molecular mechanisms of the flow-mediated aneurysm pathology, we are also developing in vitro cell culture systems to complement the in vivo study. Our current effort in endovascular device development focuses on novel stents that alters the aneurysmal flow to promote thrombotic occlusion as well as favorable remodeling. Realization of an

  6. A study of the hemodynamics of anterior communicating artery aneurysms

    NASA Astrophysics Data System (ADS)

    Cebral, Juan R.; Castro, Marcelo A.; Putman, Christopher M.

    2006-03-01

    In this study, the effects of unequal physiologic flow conditions in the internal carotid arteries on the intra-aneurysmal hemodynamics of anterior communicating artery aneurysms were investigated. Patient-specific vascular computational fluid dynamics models of five cerebral aneurysms were constructed from bilateral 3D rotational angiography images. The aneurysmal hemodynamics was analyzed under a range of physiologic flow conditions including the effects of unequal mean flows and phase shifts between the flow waveforms of the left and right internal carotid arteries. A total of five simulations were performed for each patient, and unsteady wall shear stress (WSS) maps were created for each flow condition. Time dependent curves of average WSS magnitude over selected regions on the aneurysms were constructed and used to analyze the influence of the inflow conditions. It was found that mean flow imbalances in the feeding vessels tend to shift the regions of elevated WSS (flow impingement region) towards the dominating inflow jet and to change the magnitude of the WSS peaks. However, the overall qualitative appearance of the WSS distribution and velocity simulations is not substantially affected. In contrast, phase differences tend to increase the temporal complexity of the hemodynamic patterns and to destabilize the intra-aneurysmal flow pattern. However, these effects are less important when the A1 confluence is less symmetric, i.e. dominated by one of the A1 segments. Conditions affecting the flow characteristics in the parent arteries of cerebral aneurysms with more than one avenue of inflow should be incorporated into flow models.

  7. Image based numerical simulation of hemodynamics in a intracranial aneurysm

    NASA Astrophysics Data System (ADS)

    Le, Trung; Ge, Liang; Sotiropoulos, Fotis; Kallmes, David; Cloft, Harry; Lewis, Debra; Dai, Daying; Ding, Yonghong; Kadirvel, Ramanathan

    2007-11-01

    Image-based numerical simulations of hemodynamics in a intracranial aneurysm are carried out. The numerical solver based on CURVIB (curvilinear grid/immersed boundary method) approach developed in Ge and Sotiropoulos, JCP 2007 is used to simulate the blood flow. A curvilinear grid system that gradually follows the curved geometry of artery wall and consists of approximately 5M grid nodes is constructed as the background grid system and the boundaries of the investigated artery and aneurysm are treated as immersed boundaries. The surface geometry of aneurysm wall is reconstructed from an angiography study of an aneurysm formed on the common carotid artery (CCA) of a rabbit and discretized with triangular meshes. At the inlet a physiological flow waveform is specified and direct numerical simulations are used to simulate the blood flow. Very rich vortical dynamics is observed within the aneurysm area, with a ring like vortex sheds from the proximal side of aneurysm, develops and impinge onto the distal side of the aneurysm as flow develops, and destructs into smaller vortices during later cardiac cycle. This work was supported in part by the University of Minnesota Supercomputing Institute.

  8. Numerical simulation of aneurysm hemodynamics

    NASA Astrophysics Data System (ADS)

    MacVicar, Stephen; Huynh, Sophia; Rossmann, Jenn

    2003-11-01

    Rupture of intracranial aneurysms is the leading cause of spontaneous subarachnoid hemorrhage, with high rates of morbidity and mortality. Numerical simulations of flow in a variety of two-dimensional and three-dimensional saccular aneurysm geometries were performed to evaluate possible sites and mechanisms for aneurysm growth and rupture. The governing equations were solved in their finite volume formulation for both steady and pulsatile flows. Recirculation zones and secondary flows were observed in aneurysms and arteries. Regions of elevated and oscillating shear stress were observed, often at the aneurysm's distal shoulder. The influence of several geometric factors, including vessel curvature, branching angle, and aneurysm shape, on flow patterns and fluid mechanical forces was studied, with the goal of assessing the risks posed by given aneurysm geometry.

  9. Time evolution and hemodynamics of cerebral aneurysms

    NASA Astrophysics Data System (ADS)

    Sforza, Daniel M.; Putman, Christopher; Tateshima, Satoshi; Viñuela, Fernando; Cebral, Juan

    2011-03-01

    Cerebral aneurysm rupture is a leading cause of hemorrhagic strokes. Because they are being more frequently diagnosed before rupture and the prognosis of subarachnoid hemorrhage is poor, clinicians are often required to judge which aneurysms are prone to progression and rupture. Unfortunately, the processes of aneurysm initiation, growth and rupture are not well understood. Multiple factors associated to these processes have been identified. Our goal is to investigate two of them, arterial hemodynamics (using computational fluid dynamics) and the peri-aneurysmal environment, by studying a group of growing cerebral aneurysms that are followed longitudinally in time. Six patients with unruptured untreated brain aneurysms which exhibited growth during the observation period were selected for the study. Vascular models of each aneurysm at each observation time were constructed from the corresponding computed tomography angiography (CTA) images. Subsequently, models were aligned, and geometrical differences quantified. Blood flow was modeled with the 3D unsteady incompressible Navier-Stokes equation for a Newtonian fluid, and wall shear stress distribution and flow patterns were calculated and visualized. Analysis of the simulations and changes in geometry revealed asymmetric growth patterns and suggests that areas subject to vigorous flows, i.e. relative high wall shear stress and concentrated streamlines patterns; correspond to regions of aneurysm growth. Furthermore, in some cases the geometrical evolution of aneurysms is clearly affected by contacts with bone structures and calcifications in the wall, and as a consequence the hemodynamics is greatly modified. Thus, in these cases the peri-aneurysmal environment must be considered when analyzing aneurysm evolution.

  10. Hemodynamic Impact of a Spontaneous Cervical Dissection on an Ipsilateral Saccular Aneurysm

    PubMed Central

    See, Alfred P.; Penn, David L.; Du, Rose; Frerichs, Kai U

    2016-01-01

    The dynamic, hemodynamic impact of a cervical dissection on an ipsilateral, intracranial saccular aneurysm has not been well illustrated. This 45-year-old female was found to have a small, supraclinoid aneurysm ipsilateral to a spontaneous cervical internal carotid artery dissection. With healing of the dissection, the aneurysm appeared to have significantly enlarged. Retrospective review of the magnetic resonance imaging (MRI) at the time of the initial dissection demonstrated thrombus, similar in overall morphology to the angiographic appearance of the "enlarged" aneurysm. As the dissection healed far proximal to the intradural portion of the internal carotid artery, this suggested that the aneurysm was likely a typical, saccular posterior communicating artery aneurysm that had thrombosed and then recanalized secondary to flow changes from the dissection. The aneurysm was coiled uneventfully, in distinction from more complex treatment approaches such as flow diversion or proximal occlusion to treat an enlarging, dissecting pseudoaneurysm. This case illustrates that flow changes from cervical dissections may result in thrombosis of downstream saccular aneurysms. With healing, these aneurysms may recanalize and be misidentified as enlarging dissecting pseudoaneurysms. Review of an MRI from the time of the dissection facilitated the conclusion that the aneurysm was a saccular posterior communicating artery aneurysm, influencing treatment approach. PMID:27790401

  11. Endovascular Treatment of Extracranial Internal Carotid Aneurysms Using Endografts

    SciTech Connect

    Baldi, Sebastian Rostagno, Roman D.; Zander, Tobias; Llorens, Rafael; Schonholz, Claudio; Maynar, Manuel

    2008-03-15

    Aneurysms of the extracranial internal carotid artery (EICA) are infrequent. They are difficult to treat with conventional surgery because of their distal extension into the skull base. We report three cases of EICA aneurysms in two symptomatic patients successfully treated with polytetrafluoroethylene self-expanding endografts using an endovascular approach. The aneurysms were located distal to the carotid bifurcation and extended to the subpetrous portion of the internal carotid artery.

  12. Successful Endovascular Treatment of a Left Common Carotid Artery Aneurysm Following Failed Surgery of a Right Common Carotid Artery Aneurysm

    SciTech Connect

    Cil, Barbaros E. Ucar, Ibrahim; Ozsoy, Fatma; Arat, Anil; Yorgancioglu, Cem; Boeke, Erkmen

    2005-04-15

    Aneurysm of the common carotid artery is a rare and serious disease requiring prompt treatment in order to avoid neurologic complications. A 39-year-old man presented with voice impairment and a pulsatile mass at the right side of his neck and was found by color Doppler examination to have bilateral common carotid artery aneurysms of unknown origin. The right-sided large aneurysm was treated with placement of an 8 mm interposition Gore-Tex graft between the right common and internal carotid arteries. The surgical graft thrombosed 7 days after the surgery but the left-sided aneurysm was successfully treated by a Jostent peripheral stent-graft. Color Doppler examination showed a patent stent and no filling of the aneurysm on his first and sixth-month follow-up. Bilateral common carotid artery aneurysm is an exceptionally unusual condition and endovascular treatment of carotid artery aneurysms with covered stents may become an effective treatment alternative for these lesions.

  13. Computational hemodynamic study of intracranial aneurysms coexistent with proximal artery stenosis

    NASA Astrophysics Data System (ADS)

    Castro, Marcelo A.; Peloc, Nora L.; Putman, Christopher M.; Cebral, Juan R.

    2012-03-01

    Intracranial aneurysms and artery stenosis are vascular diseases with different pathophysiological characteristics. However, although unusual, aneurysms may coexist in up to 5% of patients with stenotic plaque, according to a previous study. Another study showed that incidental detection of cerebral aneurysm in the same cerebral circulation as the stenotic plaque was less than 2%. Patients with concomitant carotid artery stenosis and unruptured intracranial aneurysms 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 purpose of this study is to investigate the intraaneurysmal hemodynamic changes before and after treatment of stenotic plaque. Idealized models were constructed with different stenotic grade, distance and relative position to the aneurysm. Digital removal of the stenotic plaque was performed in the reconstructed model of a patient with both pathologies. Computational fluid dynamic simulations were performed using a finite element method approach. Blood velocity field and hemodynamic forces were recorded and analyzed. Changes in the flow patterns and wall shear stress values and distributions were observed in both ideal and image-based models. Detailed investigation of wall shear stress distributions in patients with both pathologies is required to make the best management decision.

  14. Hemodynamic Alterations after Stent Implantation in 15 Cases of Intracranial Aneurysms

    PubMed Central

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

    2016-01-01

    Background Stent-assisted coiling technology has been widely used in the treatment of intracranial aneurysms. In current study, we investigated the intra-aneurysmal hemodynamic alterations after stent implantation and its association with aneurysm location. Methods 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 patient-specific geometries before and after stenting, we built virtual stenting computational fluid dynamics (CFD) simulation models. Results Before and after 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; and the spatially averaged value of flow velocity in the perpendicular plane of 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, WSS in ICA-OphA aneurysms and PcoA aneurysms decreased by 14.4% (P = 0.012) and 16.6% (P = 0.018) respectively, and flow velocity also reduced by 10.3% (P = 0.029) and 10.5% (P = 0.013), respectively. Changes in WSS, flow velocity, and pressure were not significantly different between ICA-OphA aneurysms and PcoA aneurysms (P > 0.05). Stent implantation did not significantly change the peak systolic pressure in both aneurysm types. Conclusion After stent implantation, intra-aneurysmal flow velocity and WSS decreased independent of aneurysm type (ICA-OphA and PcoA). Little change was observed on peak systolic pressure. PMID:26746828

  15. Cortical non-aneurysmal subarachnoid hemorrhage post-carotid endarterectomy: a case report and literature review.

    PubMed

    Thanabalasundaram, Gopiga; Hernández-Durán, Silvia; Leslie-Mazwi, Thabele; Ogilvy, Christopher S

    2013-01-01

    Cerebral hyperperfusion syndrome is a well-recognized and potentially fatal complication of carotid revascularization. However, the occurrence of non-aneurysmal subarachnoid hemorrhage as a manifestation of cerebral hyperperfusion syndrome post-carotid endarterectomy is uncommon. We report a case of a patient who presented with headache following carotid endarterectomy for a critically occluded common carotid artery. This progressed to deteriorating consciousness and seizures. Investigations revealed a left cortical non-aneurysmal subarachnoid hemorrhage. Non-aneurysmal subarachnoid hemorrhage is a rare post-operative complication of carotid endarterectomy. Immediate management with aggressive blood pressure control is key to prevent permanent neurological deficits. Cerebral hyperperfusion syndrome (CHS) after carotid revascularization procedures is an uncommon and potentially fatal complication. Pathophysiologically it is attributed to impaired autoregulatory mechanisms and results in disruption of cerebral hemodynamics with increased regional cerebral blood flow (Cardiol Rev 20:84-89, 2012; J Vasc Surg 49:1060-1068, 2009). The condition is characterized by throbbing ipsilateral frontotemporal or periorbital headache. Other symptoms include vomiting, confusion, macular edema, focal motor seizures with frequent secondary generalization, focal neurological deficits, and intraparenchymal or subarachnoid hemorrhage (SAH) (Lancet Neurol 4:877-888, 2005). The incidence of CHS varies from 0.2% to 18.9% after carotid endarterectomy (CEA), with a typical reported incidence of less than 3% in larger studies (Cardiol Rev 20:84-89, 2012; Neurosurg 107:1130-1136, 2007). Uncontrolled hypertension, an arterially isolated cerebral hemisphere, and contralateral carotid occlusion are the main risk factors (Lancet Neurol 4:877-888, 2005; J Neurol Neurosurg Psychiatry 83:543-550, 2012). We present a case of non-aneurysmal SAH after CEA, with focus on its presentation, risk factors

  16. Extracranial carotid artery aneurysm due to Behcet's disease.

    PubMed

    Albeyoglu, Sebnem; Cinar, Bayer; Eren, Tunc; Filizcan, Ugur; Bayserke, Olgar; Aslan, Cenk

    2010-12-01

    Behçet's disease is a chronic systemic inflammatory disorder associated with recurrent oral and genital ulcers and iritis. Vascular lesions are encountered in 7%-29% of patients, gravely affecting the course of the disease. Extracranial carotid aneurysms due to Behçet's disease are extremely rare. We describe a surgically treated case of Behçet's disease in a 28-year-old man who presented with a rapidly enlarging left common carotid artery aneurysm.

  17. 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

  18. An internal carotid artery aneurysm presenting with dysarthria.

    PubMed

    Davey, P T; Rychlik, I; O'Donnell, M; Baker, R; Rennie, I

    2013-10-01

    A 72-year-old woman presented to her general practitioner with a 4-week history of right neck swelling. Clinical examination elicited a pulsatile mass consistent with a carotid artery aneurysm. Five days later the patient noticed her tongue movements had become awkward with associated dysarthria. Computed tomography confirmed a 4cm internal carotid artery aneurysm arising just distally to the carotid bifurcation. She proceeded to transfemoral diagnostic carotid angiography. Balloon occlusion of the right internal carotid artery origin was performed for a ten-minute period without any neurological deficit. The decision was taken to proceed to surgical ligation of the origin of the internal carotid artery. Her symptoms of dysarthria have resolved.

  19. Association between Internal Carotid Artery Morphometry and Posterior Communicating Artery Aneurysm

    PubMed Central

    Kim, Dae-Won

    2007-01-01

    Purpose The goal of this study was to directly measure the association between the internal carotid artery (ICA) morphometry and the presence of ICA-posterior communicating artery (PCOM) aneurysm. Materials and Methods The authors intraoperatively measured the length of the supraclinoid ICA because it is impossible to radiologically determine the exact location of the anterior clinoid process. We used an image analyzer with a CT angiogram to measure the angle between the skull midline and the terminal segment of the ICA (ICA angle), as well as the diameter of the ICA. The lengths and diameters of the supraclinoid ICA and the ICA angle were compared among PCOM aneurysms, anterior communicating artery (ACOM) aneurysms, and middle cerebral artery (MCA) bifurcation aneurysms (n = 27 each). Additionally, the lengths and the diameters of M1 and A1 were compared for each aneurysm. Results The lengths of the supraclinoid ICA were 11.9 ± 2.3mm. The lengths of the supraclinoid ICA in patients with ICA-PCOM aneurysms (9.7 ± 2.8mm) were shorter than those of patients with ACOM aneurysms (13.8 ± 2.2mm, Student's t-test, p < 0.001) and with MCA bifurcation aneurysms (12.2 ± 1.9 mm, Student's t-test, p < 0.001). The diameters of the supraclinoid ICA and A1 in patients with ACOM aneurysms were larger than those in patients with MCA bifurcation aneurysms (Student's t-test, p < 0.05). There were no significant differences in the lengths of M1 and A1, ICA angle, or diameter of M1 for each aneurysm. Conclusion These results suggest that the relatively shorter length of the supraclinoid ICA may be a novel risk factor for the development of ICA-PCOM aneurysm with higher hemodynamic stress. PMID:17722235

  20. Quantifying the Large-Scale Hemodynamics of Intracranial Aneurysms

    PubMed Central

    Byrne, G.; Mut, F.; Cebral, J.

    2013-01-01

    BACKGROUND AND PURPOSE Hemodynamics play an important role in the mechanisms that govern the initiation, growth, and possible rupture of intracranial aneurysms. The purpose of this study was to objectively characterize these dynamics, classify them, and connect them to aneurysm rupture. MATERIALS AND METHODS Image-based computational fluid dynamic simulations were used to re-create the hemodynamics of 210 patient-specific intracranial aneurysm geometries. The hemodynamics were then classified according to their spatial complexity and temporal stability by using quantities derived from vortex core lines and proper orthogonal decomposition. RESULTS The quantitative classification was compared with a previous qualitative classification performed by visual inspection. Receiver operating characteristic curves provided area-under-the-curve estimates for spatial complexity (0.905) and temporal stability (0.85) to show that the 2 classifications were in agreement. Statistically significant differences were observed in the quantities describing the hemodynamics of ruptured and unruptured intracranial aneurysms. Specifically, ruptured aneurysms had more complex and more unstable flow patterns than unruptured aneurysms. Spatial complexity was more strongly associated with rupture than temporal stability. CONCLUSIONS Complex-unstable blood flow dynamics characterized by longer core line length and higher entropy could induce biologic processes that predispose an aneurysm for rupture. PMID:23928142

  1. Correlation Between Aneurysm Size and Hemodynamics in One Individual with Multiple Small Intracranial Aneurysms

    PubMed Central

    Britz, Gavin

    2016-01-01

    Objective A large number of cases are needed in the patient-specific modeling of intracranial aneurysms to establish the statistical significance due to individual variation of risk factors that are difficult to account for. However, these risk factors are critical in hemorrhage risk as demonstrated in large clinical studies. Rupture risks for aneurysms in an individual are easier to compare because these aneurysms are under the same physiological environment, and their only differences are the local hemodynamic factors associated with their anatomic locations. Methods Eight small aneurysms (< 7 mm) from one individual were analyzed using patient-specific hemodynamic modeling. Four scenarios with different perfusion assumptions were performed to account for the flow rate at two smaller communicating arteries. Wall shear stresses (WSS) at these aneurysms were compared to determine their relationship with the aneurysm size. Results Each of the three largest aneurysms is either the most proximal or distal aneurysm in a given artery so that blood pressure does not have a direct influence on aneurysm size. No wall shear stress-derived hemodynamic variables are found to be related to aneurysm size. Discussion A study of multiple aneurysms from one individual offers a unique opportunity to examine various hemodynamic factors without selection biases. Aneurysms greater than 4 mm (Group 1) have a higher product of maximum WSS and area of low WSS; aneurysms smaller than 4 mm (Group 2) have a lower product of maximum WSS and area of low WSS. In addition, aneurysm size is linearly correlated with the flow rate at the parent artery in each group. PMID:27555981

  2. Correlation Between Aneurysm Size and Hemodynamics in One Individual with Multiple Small Intracranial Aneurysms.

    PubMed

    Jou, Liangder; Britz, Gavin

    2016-07-12

    Objective A large number of cases are needed in the patient-specific modeling of intracranial aneurysms to establish the statistical significance due to individual variation of risk factors that are difficult to account for. However, these risk factors are critical in hemorrhage risk as demonstrated in large clinical studies. Rupture risks for aneurysms in an individual are easier to compare because these aneurysms are under the same physiological environment, and their only differences are the local hemodynamic factors associated with their anatomic locations. Methods Eight small aneurysms (< 7 mm) from one individual were analyzed using patient-specific hemodynamic modeling. Four scenarios with different perfusion assumptions were performed to account for the flow rate at two smaller communicating arteries. Wall shear stresses (WSS) at these aneurysms were compared to determine their relationship with the aneurysm size. Results Each of the three largest aneurysms is either the most proximal or distal aneurysm in a given artery so that blood pressure does not have a direct influence on aneurysm size. No wall shear stress-derived hemodynamic variables are found to be related to aneurysm size. Discussion A study of multiple aneurysms from one individual offers a unique opportunity to examine various hemodynamic factors without selection biases. Aneurysms greater than 4 mm (Group 1) have a higher product of maximum WSS and area of low WSS; aneurysms smaller than 4 mm (Group 2) have a lower product of maximum WSS and area of low WSS. In addition, aneurysm size is linearly correlated with the flow rate at the parent artery in each group.

  3. Surgical management of unruptured posterior carotid artery wall aneurysms.

    PubMed

    O'Shaughnessy, Brian A; Getch, Christopher C; Bendok, Bernard R; Batjer, H Hunt

    2003-07-15

    Intracranial aneurysms arising from the posterior wall of the supraclinoid carotid artery are extremely common lesions. The aneurysm dilation typically occurs in immediate proximity to the origin of the posterior communicating artery and, less commonly, the anterior choroidal artery (AChA). Because of the increasingly widespread use of noninvasive neuroimaging methods to evaluate patients believed to harbor cerebral lesions, many of these carotid artery aneurysms are now documented in their unruptured state, prior to occurrence of subarachnoid hemorrhage. Based on these factors, the management of unruptured posterior carotid artery (PCA) wall aneurysms is an important element of any neurosurgical practice. Despite impressive recent advances in endovascular therapy, the placement of microsurgical clips to exclude aneurysms with preservation of all afferent and efferent vasculature remains the most efficacious and durable therapy. To date, an optimal outcome is only achieved when the neurosurgeon is able to combine systematic preoperative neurovascular assessment with meticulous operative technique. In this report, the authors review their surgical approach to PCA wall aneurysms, which is greatly based on the extensive neurovascular experience of the senior author. Focus is placed on their methods of preoperative evaluation and operative technique, with emphasis on neurovascular anatomy and the significance of oculomotor nerve compression. They conclude by discussing surgery-related complications, with a particular focus on intraoperative rupture of aneurysms and their management, and the postoperative ischemic AChA syndrome.

  4. Hemodynamics before and after bleb formation in cerebral aneurysms

    NASA Astrophysics Data System (ADS)

    Cebral, Juan R.; Radaelli, Alessandro; Frangi, Alejandro; Putman, Christopher M.

    2007-03-01

    We investigate whether blebs in cerebral aneurysms form in regions of low or high wall shear stress (WSS), and how the intraaneurysmal hemodynamic pattern changes after bleb formation. Seven intracranial aneurysms harboring well defined blebs were selected from our database and subject-specific computational models were constructed from 3D rotational angiography. For each patient, a second anatomical model representing the aneurysm before bleb formation was constructed by smoothing out the bleb. Computational fluid dynamics simulations were performed under pulsatile flow conditions for both models of each aneurysm. In six of the seven aneurysms, the blebs formed in a region of elevated WSS associated to the inflow jet impaction zone. In one, the bleb formed in a region of low WSS associated to the outflow zone. In this case, the inflow jet maintained a fairly concentrated structure all the way to the outflow zone, while in the other six aneurysms it dispersed after impacting the aneurysm wall. In all aneurysms, once the blebs formed, new flow recirculation regions were formed inside the blebs and the blebs progressed to a state of low WSS. Assuming that blebs form due to a focally damaged arterial wall, these results seem to indicate that the localized injury of the vessel wall may be caused by elevated WSS associated with the inflow jet. However, the final shape of the aneurysm is probably also influenced by the peri-aneurysmal environment that can provide extra structural support via contact with structures such as bone or dura matter.

  5. Intracranial Pseudoaneurysms, Fusiform Aneurysms and Carotid-Cavernous Fistulas

    PubMed Central

    Lv, Xianli; Jiang, Chuhan; Li, Youxiang; Lv, Ming; Zhang, Jingbo; Wu, Zhongxue

    2008-01-01

    Summary The study assessed the effectiveness and safety of endovascular covered stents in the management of intracranial pseudoaneurysms, fusiform aneurysms and direct carotid-cavernous fistulas. Fourteen endovascular covered stents were used to repair three pseudoaneurysms, six fu-siform aneurysms and six direct carotid-cavernous fistulas. Aneurysms were in the carotid artery in seven cases, in the vertebral artery two cases. It was not possible to treat two additional cases transcutaneously for technical reasons
2/15. Percutaneous closure of the lesions with an endovascular covered stent was successful in 13 of 15 cases. Initial follow-up showed good stent patency. No complications were observed after stent implantation. During follow-up, stent thromboses were detected in two of nine patients with follow-up digital subtracted angiography. One carotid-cavernous fistula of Barrow Type A transformed into Barrow Type D at nine month follow-up study was cured with a procudure of Onyx-18 injection. Endovascular covered stents may be an option for percutaneous closure of intracranial pseudoaneurysms, fusiform aneurysms and direct carotid-cavernous fistulas. Endoluminal vascular repair with covered stents offers an alternative therapeutic approach to conventional modalities. PMID:20557743

  6. Exposure of the intracavernous carotid artery in aneurysm surgery.

    PubMed

    Ohmoto, T; Nagao, S; Mino, S; Ito, T; Honma, Y; Fujiwara, T

    1991-02-01

    The pterional intradural approach was used in five cases of large and giant carotid-ophthalmic aneurysms and in two cases of intracavernous aneurysms that arose from the anterior siphon knee in the cavernous sinus (CS) and extended into the carotid cistern. In four cases of large carotid-ophthalmic aneurysms removal of the anterior clinoid process and the roof of the optic canal gave easy access to the pericarotid ring. The anteromedial part of the pericarotid ring was dissected to expose the extradural portion of the internal carotid artery (ICA) proximal to the neck and to make enough room between the wall of the CS and the extradural portion of the ICA, thus allowing easy clipping of the neck. In one case of a giant carotid-ophthalmic aneurysm extending into the CS with an extradural origin of the ophthalmic artery and in two cases of an intracavernous aneurysm arising from the siphon knee, neck clipping was performed by opening the lateral wall and roof of the CS after removal of the optic strut. The opening of the lateral wall anterior to the 3rd nerve facilitated wide exposure of the anterior siphon knee. The horizontal portion of the intracavernous ICA as well as the whole aspect of the aneurysm could be exposed as a result of the extended opening of the cavernous roof anterior to the posterior clinoid process. Successful operative results were obtained in all seven patients. A visual field detect as an operative complication was noted in one patient. No disturbance of ocular movements was noted.

  7. Ultrasonic Imaging of Hemodynamic Force in Carotid Blood Flow

    NASA Astrophysics Data System (ADS)

    Nitta, N.; Homma, K.

    Hemodynamic forces including blood pressure and shear stress affect vulnerable plaque rupture in arteriosclerosis and biochemical activation of endothelium such as NO production. In this study, a method for estimating and imaging shear stress and pressure gradient distributions in blood vessel as the hemodynamic force based on viscosity estimation is presented. Feasibility of this method was investigated by applying to human carotid blood flow. Estimated results of shear stress and pressure gradient distributions coincide with the ideal distributions obtained by numerical simulation and flow-phantom experiment.

  8. [Thrombosis of the ending internal carotid artery complicating giant aneurysm].

    PubMed

    Truffert, A; Jouvenot, M; Coulaud, X; Dandelot, J B

    1993-01-01

    A 30-year old man suddenly developed left hemiplegia. CT scan and cerebral angiography showed complete thrombosis of a right internal carotid giant aneurysm. Anterograde propagation of the thrombus in the parent artery led to ipsilateral hemispheric infarction, an exceptional presenting symptom of such vascular malformation. The diagnostic and etiopathogenic aspects are briefly discussed.

  9. Treatment of Carotid Siphon Aneurysms with a Microcell Stent

    PubMed Central

    Leonardi, M.; Dall’Olio, M.; Princiotta, C.; Simonetti, L.

    2008-01-01

    Summary The treatment of giant, large, multiple or wide-necked carotid siphon aneurysms has always represented a challenge for neurosurgeons and neuroradiologists. Very recently the use of stents with tiny holes has been proposed by two companies: Balt Silk Stent in Europe and Pi-peline in America. We have used the Silk stent on a few patients and describe our first case who now has an eleven month follow-up. The carotid siphon presented three converging aneurysms sharing a very large common neck. The Silk stent (Balt Extrusion, Montmorency, France) was deployed through a 4F Balt introducer. The procedure was uneventful and very quick. As soon as the stent was positioned contrast medium stagnation was displayed within the aneur-ysm. The patient’s post-operative course was normal and she was discharged three days later in good health. PMID:20557742

  10. Post-Treatment Hemodynamics of a Basilar Aneurysm and Bifurcation

    PubMed Central

    Ortega, J.; Hartman, J.; Rodriguez, J.; Maitland, D.

    2009-01-01

    To investigate whether or not a successful aneurysm treatment procedure can subject a parent artery to harmful hemodynamic stresses, computational fluid dynamics simulations are performed on a patient-specific basilar aneurysm and bifurcation before and after a virtual endovascular treatment. Prior to treatment, the aneurysm at systole is filled with a periodic train of vortex tubes, which form at the aneurysm neck and advect upwards into the dome. Following the treatment procedure however, the motion of the vortex train is inhibited by the aneurysm filling material, which confines the vortex tubes to the region beneath the aneurysm neck. Analysis of the post-treatment flow field indicates that the impingement of the basilar artery flow upon the treated aneurysm neck and the close proximity of a vortex tube to the parent artery wall increase the maximum wall shear stresses to values approximately equal to 50 Pa at systole. Calculation of the time-averaged wall shear stresses indicates that there is a 1.4 × 9 10−7 m2 area on the parent artery exposed to wall shear stresses greater than 37.9 Pa, a value shown by Fry [Circ. Res. 22(2):165–197, 1968] to cause severe damage to the endothelial cells that line the artery wall. The results of this study demonstrate that it is possible for a treatment procedure, which successfully isolates the aneurysm from the circulation and leaves no aneurysm neck remnant, to elevate the hemodynamic stresses to levels that are injurious to the artery wall. PMID:18629647

  11. Investigation of cerebral hemodynamics and collateralization in asymptomatic carotid stenoses.

    PubMed

    AlMuhanna, Khalid; Zhao, Limin; Kowalewski, Gregory; Beach, Kirk W; Lal, Brajesh K; Sikdar, Siddhartha

    2012-01-01

    Stroke is the second leading cause of death in the world, and one of the major causes of disability. Approximately 30% of ischemic strokes are due to plaque rupture in the carotid arteries. The most popular diagnostic method uses Doppler ultrasound to find the percent stenosis. However, other factors, such as the hemodynamics around the plaque may play a larger role in identifying the risk of plaque rupture. It has been shown previously in simulations that non-collateral flow in the circle of Willis (COW) could cause an increase of the intraluminal velocity around carotid plaque. This added strain may increase the vulnerability of the plaque to rupture. We investigated asymmetries in flow waveforms in the middle cerebral artery (MCA) in asymptomatic patients with carotid artery stenosis. We compared clinical results of velocity waveforms in the MCA, acquired using transcranial Doppler (TCD), with a simple linear simulation model of the intra- and extracranial arterial network to investigate the relationship between contralateral and ipsilateral flow profiles in the MCA for patients with asymptomatic carotid stenosis. In 17 out of 23 patients we found waveforms consistent with those predicted for a collateralized COW, with minimal differences in delay, velocity magnitude and resistivity index. In 6 cases, some unexpected findings were noted, such as large delays for 2 patients ≤ 50% stenosis, and a large velocity difference with low delay for 4 patients. More studies are needed to elucidate the role of incomplete intracranial collateralization on the hemodynamics around carotid plaque and to use imaging of the COW to corroborate our results.

  12. Analysis and Comparison of 2-D Hemodynamic Numerical Simulation of Elastic Aneurysm and Rigid Aneurysm

    NASA Astrophysics Data System (ADS)

    Zhao, J. W.; Ding, G. H.; Yin, W. Y.; Yang, X. J.; Shi, W. C.; Zhang, X. L.

    The objective of this study is to investigate the effect of hemodynamic parameters on the formation, growth and rupture of an aneurysm. Our simulation of the elastic and rigid aneurysm is based on a DSA or other clinic image. The simulatied results are that there are great differences in the distribution of velocity magnitude at some sections which are predicted by the two models. For the elastic wall model, the distribution of velocity magnitude of one outlet is obviously off-center, which influences the distribution of wall shear stress (WSS) and exchange of substance through the vessel wall. The currents of the distributions of WSS along the wall of aneurysm for the two models are similar. But there are obvious differences between the two models in the values especially at the neck of aneurysm. This study demonstrates obviously that the elastic wall model suits the simulation for growth and rupture of an aneurysm better.

  13. Post-Treatment Hemodynamics of a Basilar Aneurysm and Bifurcation

    SciTech Connect

    Ortega, J; Hartman, J; Rodriguez, J; Maitland, D

    2008-01-16

    Aneurysm re-growth and rupture can sometimes unexpectedly occur following treatment procedures that were initially considered to be successful at the time of treatment and post-operative angiography. In some cases, this can be attributed to surgical clip slippage or endovascular coil compaction. However, there are other cases in which the treatment devices function properly. In these instances, the subsequent complications are due to other factors, perhaps one of which is the post-treatment hemodynamic stress. To investigate whether or not a treatment procedure can subject the parent artery to harmful hemodynamic stresses, computational fluid dynamics simulations are performed on a patient-specific basilar aneurysm and bifurcation before and after a virtual endovascular treatment. The simulations demonstrate that the treatment procedure produces a substantial increase in the wall shear stress. Analysis of the post-treatment flow field indicates that the increase in wall shear stress is due to the impingement of the basilar artery flow upon the aneurysm filling material and to the close proximity of a vortex tube to the artery wall. Calculation of the time-averaged wall shear stress shows that there is a region of the artery exposed to a level of wall shear stress that can cause severe damage to endothelial cells. The results of this study demonstrate that it is possible for a treatment procedure, which successfully excludes the aneurysm from the vascular system and leaves no aneurysm neck remnant, to elevate the hemodynamic stresses to levels that are injurious to the immediately adjacent vessel wall.

  14. Combined Visualization of Vessel Deformation and Hemodynamics in Cerebral Aneurysms.

    PubMed

    Meuschke, Monique; Voss, Samuel; Beuing, Oliver; Preim, Bernhard; Lawonn, Kai

    2017-01-01

    We present the first visualization tool that combines patient-specific hemodynamics with information about the vessel wall deformation and wall thickness in cerebral aneurysms. Such aneurysms bear the risk of rupture, whereas their treatment also carries considerable risks for the patient. For the patient-specific rupture risk evaluation and treatment analysis, both morphological and hemodynamic data have to be investigated. Medical researchers emphasize the importance of analyzing correlations between wall properties such as the wall deformation and thickness, and hemodynamic attributes like the Wall Shear Stress and near-wall flow. Our method uses a linked 2.5D and 3D depiction of the aneurysm together with blood flow information that enables the simultaneous exploration of wall characteristics and hemodynamic attributes during the cardiac cycle. We thus offer medical researchers an effective visual exploration tool for aneurysm treatment risk assessment. The 2.5D view serves as an overview that comprises a projection of the vessel surface to a 2D map, providing an occlusion-free surface visualization combined with a glyph-based depiction of the local wall thickness. The 3D view represents the focus upon which the data exploration takes place. To support the time-dependent parameter exploration and expert collaboration, a camera path is calculated automatically, where the user can place landmarks for further exploration of the properties. We developed a GPU-based implementation of our visualizations with a flexible interactive data exploration mechanism. We designed our techniques in collaboration with domain experts, and provide details about the evaluation.

  15. "Subclinoid" carotid aneurysm with erosion of the anterior clinoid process and fatal intraoperative rupture.

    PubMed

    Korosue, K; Heros, R C

    1992-08-01

    We present the case of a patient with an aneurysm of the right internal carotid artery with subarachnoid hemorrhage. The aneurysm had resulted in erosion of the anterior clinoid process, but this was not recognized preoperatively. Intraoperative rupture during drilling of the clinoid necessitated vigorous packing that led to unintended carotid occlusion with subsequent fatal cerebral infarction. Preoperative recognition of the clinoid erosion may have prevented this catastrophe. To call attention to the potential for intraoperative rupture during exposure, we suggest the term subclinoid aneurysm to refer to aneurysms of the internal carotid artery that grow superolaterally and remain confined under the anterior clinoid process.

  16. 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.

  17. Hemodynamic analysis of intracranial aneurysms using phase-contrast magnetic resonance imaging and computational fluid dynamics

    NASA Astrophysics Data System (ADS)

    Zhao, Xuemei; Li, Rui; Chen, Yu; Sia, Sheau Fung; Li, Donghai; Zhang, Yu; Liu, Aihua

    2017-03-01

    Additional hemodynamic parameters are highly desirable in the clinical management of intracranial aneurysm rupture as static medical images cannot demonstrate the blood flow within aneurysms. There are two ways of obtaining the hemodynamic information—by phase-contrast magnetic resonance imaging (PCMRI) and computational fluid dynamics (CFD). In this paper, we compared PCMRI and CFD in the analysis of a stable patient's specific aneurysm. The results showed that PCMRI and CFD are in good agreement with each other. An additional CFD study of two stable and two ruptured aneurysms revealed that ruptured aneurysms have a higher statistical average blood velocity, wall shear stress, and oscillatory shear index (OSI) within the aneurysm sac compared to those of stable aneurysms. Furthermore, for ruptured aneurysms, the OSI divides the positive and negative wall shear stress divergence at the aneurysm sac.

  18. Unruptured Giant Intracranial Aneurysm of the Internal Carotid Artery: Late Ocular Symptoms.

    PubMed

    Zorić Geber, Mia; Krolo, Iva; Zrinscak, Ognjen; Tedeschi Reiner, Eugenia; Zivkovic, Dario Josip

    2016-01-01

    An unruptured giant intracranial aneurysm of the internal carotid artery may tend to present with late ocular symptoms. This is the case of a 58-year-old female patient with a giant unruptured aneurysm of the right internal carotid artery. The patient presented with exclusively progressive reduction of visual acuity and visual field defects due to the mass effect of the growing aneurysm. The rupture of the aneurysm occurred before planned treatment. Clinical suspicion and timely recognition as well as prompt treatment play an important role in the final outcome of the management of giant unruptured intracerebral aneurysms.

  19. Approximating hemodynamics of cerebral aneurysms with steady flow simulations.

    PubMed

    Geers, A J; Larrabide, I; Morales, H G; Frangi, A F

    2014-01-03

    Computational fluid dynamics (CFD) simulations can be employed to gain a better understanding of hemodynamics in cerebral aneurysms and improve diagnosis and treatment. However, introduction of CFD techniques into clinical practice would require faster simulation times. The aim of this study was to evaluate the use of computationally inexpensive steady flow simulations to approximate the aneurysm's wall shear stress (WSS) field. Two experiments were conducted. Experiment 1 compared for two cases the time-averaged (TA), peak systole (PS) and end diastole (ED) WSS field between steady and pulsatile flow simulations. The flow rate waveform imposed at the inlet was varied to account for variations in heart rate, pulsatility index, and TA flow rate. Consistently across all flow rate waveforms, steady flow simulations accurately approximated the TA, but not the PS and ED, WSS field. Following up on experiment 1, experiment 2 tested the result for the TA WSS field in a larger population of 20 cases covering a wide range of aneurysm volumes and shapes. Steady flow simulations approximated the space-averaged WSS with a mean error of 4.3%. WSS fields were locally compared by calculating the absolute error per node of the surface mesh. The coefficient of variation of the root-mean-square error over these nodes was on average 7.1%. In conclusion, steady flow simulations can accurately approximate the TA WSS field of an aneurysm. The fast computation time of 6 min per simulation (on 64 processors) could help facilitate the introduction of CFD into clinical practice.

  20. Cerebral foreign body reaction after carotid aneurysm stenting

    PubMed Central

    Lorentzen, Anastasia Orlova; Nome, Terje; Bakke, Søren Jacob; Scheie, David; Stenset, Vidar

    2016-01-01

    Flow diverter stents are new important tools in the treatment of large, giant, or wide-necked aneurysms. Their delivery and positioning may be difficult due to vessel tortuosity. Common adverse events include intracranial hemorrhage and ischemic stroke, which usually occurs within the same day, or the next few days after the procedure. We present a case where we encountered an unusual intracerebral complication several months after endovascular treatment of a large left internal carotid artery aneurysm, and where brain biopsy revealed foreign body reaction to hydrophilic polymer fragments distally to the stent site. Although previously described, embolization of polymer material from intravascular equipment is rare. We could not identify any other biopsy verified case in the literature, with this particular presentation of intracerebral polymer embolization – a multifocal inflammation spread out through the white matter of one hemisphere without hemorrhage or ischemic changes. PMID:26510943

  1. 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

  2. Hemodynamic Characteristics Regarding Recanalization of Completely Coiled Aneurysms: Computational Fluid Dynamic Analysis Using Virtual Models Comparison

    PubMed Central

    Park, Wonhyoung; Song, Yunsun; Park, Kye Jin; Koo, Hae-Won; Yang, Kuhyun

    2016-01-01

    Purpose Hemodynamic factors are considered to play an important role in initiation and progression of the recurrence after endosaccular coiling of the intracranial aneurysms. We made paired virtual models of completely coiled aneurysms which were subsequently recanalized and compared to identify hemodynamic characteristics related to the recurred aneurysmal sac. Materials and Methods We created paired virtual models of computational fluid dynamics (CFD) in five aneurysms which were initially regarded as having achieved complete occlusion and then recurred during follow-up. Paired virtual models consisted of the CFD model of 3D rotational angiography obtained in the recurred aneurysm and the control model of the initial, parent artery after artificial removal of the coiled and recanalized aneurysm. Using the CFD analysis of the virtual model, we analyzed the hemodynamic characteristics on the neck of each aneurysm before and after its recurrence. Results High wall shear stress (WSS) was identified at the cross-sectionally identified aneurysm neck at which recurrence developed in all cases. A small vortex formation with relatively low velocity in front of the neck was also identified in four cases. The aneurysm recurrence locations corresponded to the location of high WSS and/or small vortex formation. Conclusion Recanalized aneurysms revealed increased WSS and small vortex formation at the cross-sectional neck of the aneurysm. This observation may partially explain the hemodynamic causes of future recanalization after coil embolization. PMID:26958410

  3. Internal Carotid Artery Reconstruction Using Multiple Fenestrated Clips for Complete Occlusion of Large Paraclinoid Aneurysms

    PubMed Central

    Lee, Sang Kook

    2013-01-01

    Objective Although surgical techniques for clipping paraclinoid aneurysms have evolved significantly in recent times, direct microsurgical clipping of large and giant paraclinoid aneurysms remains a formidable surgical challenge. We review here our surgical experiences in direct surgical clipping of large and giant paraclinoid aneurysms, especially in dealing with anterior clinoidectomy, distal dural ring resection, optic canal unroofing, clipping techniques, and surgical complications. Methods Between September 2001 and February 2012, we directly obliterated ten large and giant paraclinoid aneurysms. In all cases, tailored orbito-zygomatic craniotomies with extradural and/or intradural clinoidectomy were performed. The efficacy of surgical clipping was evaluated with postoperative digital subtraction angiography and computed tomographic angiography. Results Of the ten cases reported, five each were of ruptured and unruptured aneurysms. Five aneurysms occurred in the carotid cave, two in the superior hypophyseal artery, two in the intracavernous, and one in the posterior wall. The mean diameter of the aneurysms sac was 18.8 mm in the greatest dimension. All large and giant paraclinoid aneurysms were obliterated with direct neck clipping without bypass. With the exception of the one intracavenous aneurysm, all large and giant paraclinoid aneurysms were occluded completely. Conclusion The key features of successful surgical clipping of large and giant paraclinoid aneurysms include enhancing exposure of proximal neck of aneurysms, establishing proximal control, and completely obliterating aneurysms with minimal manipulation of the optic nerve. Our results suggest that internal carotid artery reconstruction using multiple fenestrated clips without bypass may potentially achieve complete occlusion of large paraclinoid aneurysms. PMID:24527189

  4. Retrograde Suction Decompression with an Inahara Carotid Shunt for Clipping a Large Distal Internal Carotid Artery Aneurysm

    PubMed Central

    Park, Yong-Sook

    2017-01-01

    We describe a technique to clip a large internal carotid artery (ICA) aneurysm via a retrograde suction decompression (RSD). A large aneurysm in the right distal ICA involving the bifurcation region measuring 1.2×1.1×0.7 cm with posterior projection was managed with assisted RSD technique. The anterior choroidal artery emerged from the side wall of the aneurysm. An Inahara shunt was inserted into the ICA with neck dissection, and RSD was applied after completely clipping the aneurysm. RSD with an Inahara carotid shunt is useful for complete visualization of the aneurysm, including its surrounding structures, and for proximal control of the parent vessels, subsequently achieving satisfactory clip placement. PMID:28120578

  5. BILATERAL ANEURYSMS OF THE INTERNAL CAROTID ARTERY—Successful Surgical Approach in One Stage

    PubMed Central

    Weyand, Robert D.; Schmerl, E. F.; Rhee, James L.

    1959-01-01

    When intracranial aneurysm is suspected, carotid arteriogram should be done not only on the suspected side but always on both sides. Without surgical intervention the prognosis of bilateral aneurysms is notoriously poor. With the aid of hypothermic anesthesia it is now possible to operate on both sides in a single procedure. This was demonstrated in a case in which both carotid arteries were simultaneously occluded twice during the surgical repair of bilateral carotid aneurysms. Occlusion was done once for eight minutes and once for ten minutes, without clinical evidence of brain damage. ImagesFigure 1.Figure 2. PMID:13671362

  6. The impact of deformation of an aneurysm model under pulsatile flow on hemodynamic analysis.

    PubMed

    Kawakami, T; Takao, H; Ichikawa, C; Kamiya, K; Murayama, Y; Motosuke, M

    2016-08-01

    Hemodynamic analysis of cerebral aneurysms has been widely carried out to clarify the mechanisms of their growth and rupture. In several cases, patient-specific aneurysm models made of transparent polymers have been used. Even though periodic changes in aneurysms due to the pulsation of blood flow could be important, the deformation of the model geometry and its effect on hemodynamic evaluation has not been fully investigated. In addition, the fabrication accuracy of aneurysm models has not been evaluated even though it may affect the hemodynamic parameters to be analyzed. In this study, the fabrication accuracy of a silicone aneurysm model was investigated. Additionally, the deformation of the model under pulsatile flow as well as its correlation with flow behavior was evaluated. Consequently, a fabrication method for an aneurysm model with high accuracy was established and the importance of the wall thickness of the model was also specified.

  7. Cerebral aneurysms: relations between geometry, hemodynamics and aneurysm location in the cerebral vasculature

    NASA Astrophysics Data System (ADS)

    Passerini, Tiziano; Veneziani, Alessandro; Sangalli, Laura; Secchi, Piercesare; Vantini, Simone

    2010-11-01

    In cerebral blood circulation, the interplay of arterial geometrical features and flow dynamics is thought to play a significant role in the development of aneurysms. In the framework of the Aneurisk project, patient-specific morphology reconstructions were conducted with the open-source software VMTK (www.vmtk.org) on a set of computational angiography images provided by Ospedale Niguarda (Milano, Italy). Computational fluid dynamics (CFD) simulations were performed with a software based on the library LifeV (www.lifev.org). The joint statistical analysis of geometries and simulations highlights the possible association of certain spatial patterns of radius, curvature and shear load along the Internal Carotid Artery (ICA) with the presence, position and previous event of rupture of an aneurysm in the entire cerebral vasculature. Moreover, some possible landmarks are identified to be monitored for the assessment of a Potential Rupture Risk Index.

  8. Stretched Platinum Coil During Cerebral Aneurysm Embolization After Direct Carotid Puncture: Two Case Reports

    SciTech Connect

    Sedat, J. Chau, Y.; Litrico, S.; Rasandrarijao, D.; Lonjon, M.; Paquis, P.

    2007-11-15

    We describe two cases of coil unraveling that occurred during cerebral aneurysm embolization after direct carotid puncture. The unraveled coil was stretched and buried in the subcutaneous part of the neck. No immediate or long-term complication was observed.

  9. Changes in the intra-aneurysmal hemodynamics due to stent placement in sidewall and bifurcating cerebrovascular aneurysms

    NASA Astrophysics Data System (ADS)

    Cantón, Gádor; Levy, David I.; Lasheras, Juan C.

    2003-11-01

    We report on an in-vitro study of the alterations in the flow characteristics in saccular aneurysm resulting from very-high-porosity stenting (Neuroform^TM) across the aneurysmal neck. Two different silicone flexible models were considered representing two characteristic shapes and locations of intracranial aneurysms. A Digital Particle Image Velocimetry (DPIV) system was used to measure the in-vitro pulsatile velocity field within the aneurysm, at the aneurysm neck-parent artery interface, and within the parent artery. A programmable pulsatile pump is used to supply the parent artery with the waveform corresponding to the flow in the internal carotid artery. In the case of the sidewall aneurysms, three stents were placed and measurements inside the aneurysmal pouch were taken after the deployment of each stent. Two crossing stents were placed in a Y configuration in the case of the bifurcating aneurysm and measurements were taken after deployment of both of them. Placing stents across the aneurysmal neck of sidewall and bifurcating cerebrovascular aneurysms does not modify the general features of the flow (a persistent three-dimensional swirling motion), but results in a small but measurable reduction in the magnitude of the peak velocity inside the aneurysmal pouch (7-8%). In the sidewall case, the reduction in the peak velocity is shown to be enhanced to 15-20% after placing the three stents.

  10. Numerical predictions of hemodynamics following surgeries in cerebral aneurysms

    NASA Astrophysics Data System (ADS)

    Rayz, Vitaliy; Lawton, Michael; Boussel, Loic; Leach, Joseph; Acevedo, Gabriel; Halbach, Van; Saloner, David

    2014-11-01

    Large cerebral aneurysms present a danger of rupture or brain compression. In some cases, clinicians may attempt to change the pathological hemodynamics in order to inhibit disease progression. This can be achieved by changing the vascular geometry with an open surgery or by deploying a stent-like flow diverter device. Patient-specific CFD models can help evaluate treatment options by predicting flow regions that are likely to become occupied by thrombus (clot) following the procedure. In this study, alternative flow scenarios were modeled for several patients who underwent surgical treatment. Patient-specific geometries and flow boundary conditions were obtained from magnetic resonance angiography and velocimetry data. The Navier-Stokes equations were solved with a finite volume solver Fluent. A porous media approach was used to model flow-diverter devices. The advection-diffusion equation was solved in order to simulate contrast agent transport and the results were used to evaluate flow residence time changes. Thrombus layering was predicted in regions characterized by reduced velocities and shear stresses as well as increased flow residence time. The simulations indicated surgical options that could result in occlusion of vital arteries with thrombus. Numerical results were compared to experimental and clinical MRI data. The results demonstrate that image-based CFD models may help improve the outcome of surgeries in cerebral aneurysms. acknowledge R01HL115267.

  11. Effect of Hemodynamics on Outcome of Subtotally Occluded Paraclinoid Aneurysms after Stent-Assisted Coil Embolization

    PubMed Central

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

    2016-01-01

    BACKGROUND and OBJECTIVE Endovascular treatment of paraclinoid aneurysms is preferred in clinical practice. Flow alterations caused by stents and coils may affect treatment outcome. Our aim was to assess hemodynamic changes following stent-assisted coil embolization in subtotally embolized paraclinoid aneurysms with residual necks that were predisposed to recanalization. METHODS We studied 27 paraclinoid aneurysms (seven recanalized and 20 stable) treated with coils and Enterprise™ stents. Computational fluid dynamics simulations were performed on patient-specific aneurysm geometries using virtual stenting and porous media technology. RESULTS After stent placement in 27 cases, aneurysm flow velocity decreased significantly, 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. Compared between 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). CONCLUSION Aneurysm flow velocity can be significantly decreased by stent placement and coil embolization. However, hemodynamics at the aneurysm neck plane was 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 stent-assisted coil embolization. PMID:26610731

  12. 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

  13. Verification of a research prototype for hemodynamic analysis of cerebral aneurysms.

    PubMed

    Suzuki, Takashi; Ioan Nita, Cosmin; Rapaka, Saikiran; Takao, Hiroyuki; Mihalef, Viorel; Fujimura, Soichiro; Dahmani, Chihebeddine; Sharma, Puneet; Mamori, Hiroya; Ishibashi, Toshihiro; Redel, Thomas; Yamamoto, Makoto; Murayama, Yuichi

    2016-08-01

    Owing to its clinical importance, there has been a growing body of research on understanding the hemodynamics of cerebral aneurysms. Traditionally, this work has been performed using general-purpose, state-of-the-art commercial solvers. This has meant requiring engineering expertise for making appropriate choices on the geometric discretization, time-step selection, choice of boundary conditions etc. Recently, a CFD research prototype has been developed (Siemens Healthcare GmbH, Prototype - not for diagnostic use) for end-to-end analysis of aneurysm hemodynamics. This prototype enables anatomical model preparation, hemodynamic computations, advanced visualizations and quantitative analysis capabilities. In this study, we investigate the accuracy of the hemodynamic solver in the prototype against a commercially available CFD solver ANSYS CFX 16.0 (ANSYS Inc., Canonsburg, PA, www.ansys.com) retrospectively on a sample of twenty patient-derived aneurysm models, and show good agreement of hemodynamic parameters of interest.

  14. Hemodynamic effects of long-term morphological changes in the human carotid sinus.

    PubMed

    Seong, Jaehoon; Jeong, Woowon; Smith, Nataliya; Towner, Rheal A

    2015-04-13

    Previous investigations of morphology for human carotid artery bifurcation from infancy to young adulthood found substantial growth of the internal carotid artery with advancing age, and the development of the carotid sinus at the root of the internal carotid artery during teenage years. Although the reasons for the appearance of the carotid sinus are not clearly understood yet, it has been hypothesized that the dilation of the carotid sinus serves to support pressure sensing, and slows the blood flow to reduce pulsatility to protect the brain. In order to understand this interesting evolvement at the carotid bifurcation in the aspects of fluid mechanics, we performed in vitro phase-contrast MR flow experiments using compliant silicone replicas of age-dependent carotid artery bifurcations. The silicone models in childhood, adolescence, and adulthood were fabricated using a rapid prototyping technique, and incorporated with a bench-top flow mock circulation loop using a computer-controlled piston pump. The results of the in vitro flow study showed highly complex flow characteristics at the bifurcation in all age-dependent models. However, the highest magnitude of kinetic energy was found at the internal carotid artery in the child model. The high kinetic energy in the internal carotid artery during childhood might be one of the local hemodynamic forces that initiate morphological long-term development of the carotid sinus in the human carotid bifurcation.

  15. Giant Extracranial Aneurysm of the Internal Carotid Artery in Neurofibromatosis Type 1

    PubMed Central

    Moratti, C.; Andersson, T.

    2012-01-01

    Summary Neurofibromatosis type 1 (NF-1) is an autosomal dominant disorder characterized by cutaneous pigmentations, neurofibromas, Lisch nodules and neuroectodermal tumors. Supra-aortic vessel aneurysms may affect patients with NF-1 and can be associated with rupture, ischemic complications and compression symptoms. We describe a 48-year-old woman with NF-1 and an extracranial 3×5 cm right internal carotid artery aneurysm. After balloon test occlusion the patient was treated with parent artery sacrifice which led to significant shrinkage on follow-up MR and reduction of compression symptoms. The literature concerning internal carotid artery aneurysms associated with NF-1 is reviewed evaluating the possible therapeutic options. PMID:22958775

  16. Influence of Parent Artery Segmentation and Boundary Conditions on Hemodynamic Characteristics of Intracranial Aneurysms

    PubMed Central

    Hua, Yufeng; Oh, Je Hoon

    2015-01-01

    Purpose The purpose of this study is to explore the influence of segmentation of the upstream and downstream parent artery and hemodynamic boundary conditions (BCs) on the evaluated hemodynamic factors for the computational fluid dynamics (CFD) analysis of intracranial aneurysms. Materials and Methods Three dimensional patient-specific aneurysm models were analyzed by applying various combinations of inlet and outlet BCs. Hemodynamic factors such as velocity pattern, streamline, wall shear stress, and oscillatory shear index at the systolic time were visualized and compared among the different cases. Results Hemodynamic factors were significantly affected by the inlet BCs while there was little influence of the outlet BCs. When the inlet length was relatively short, different inlet BCs showed different hemodynamic factors and the calculated hemodynamic factors were also dependent on the inlet length. However, when the inlet length (L) was long enough (L>20D, where D is the diameter of inlet section), the hemodynamic factors became similar regardless of the inlet BCs and lengths. The error due to different inlet BCs was negligible. The effect of the outlet length on the hemodynamic factors was similar to that of the inlet length. Conclusion Simulated hemodynamic factors are highly sensitive to inlet BCs and upstream parent artery segmentation. The results of this work can provide an insight into how to build models and to apply BCs for more accurate estimation of hemodynamic factors from CFD simulations of intracranial aneurysms. PMID:26256976

  17. Image-based modeling of hemodynamics in coronary artery aneurysms caused by Kawasaki disease.

    PubMed

    Sengupta, Dibyendu; Kahn, Andrew M; Burns, Jane C; Sankaran, Sethuraman; Shadden, Shawn C; Marsden, Alison L

    2012-07-01

    Kawasaki Disease (KD) is the leading cause of acquired pediatric heart disease. A subset of KD patients develops aneurysms in the coronary arteries, leading to increased risk of thrombosis and myocardial infarction. Currently, there are limited clinical data to guide the management of these patients, and the hemodynamic effects of these aneurysms are unknown. We applied patient-specific modeling to systematically quantify hemodynamics and wall shear stress in coronary arteries with aneurysms caused by KD. We modeled the hemodynamics in the aneurysms using anatomic data obtained by multi-detector computed tomography (CT) in a 10-year-old male subject who suffered KD at age 3 years. The altered hemodynamics were compared to that of a reconstructed normal coronary anatomy using our subject as the model. Computer simulations using a robust finite element framework were used to quantify time-varying shear stresses and particle trajectories in the coronary arteries. We accounted for the cardiac contractility and the microcirculation using physiologic downstream boundary conditions. The presence of aneurysms in the proximal coronary artery leads to flow recirculation, reduced wall shear stress within the aneurysm, and high wall shear stress gradients at the neck of the aneurysm. The wall shear stress in the KD subject (2.95-3.81 dynes/sq cm) was an order of magnitude lower than the normal control model (17.10-27.15 dynes/sq cm). Particle residence times were significantly higher, taking 5 cardiac cycles to fully clear from the aneurysmal regions in the KD subject compared to only 1.3 cardiac cycles from the corresponding regions of the normal model. In this novel quantitative study of hemodynamics in coronary aneurysms caused by KD, we documented markedly abnormal flow patterns that are associated with increased risk of thrombosis. This methodology has the potential to provide further insights into the effects of aneurysms in KD and to help risk stratify patients for

  18. Ophthalmic artery aneurysm treated by surgical clipping and balloon-assisted temporary carotid occlusion.

    PubMed

    Dehdashti, Amir R

    2015-07-01

    A 29-year-old woman is diagnosed with a large broad-base right ophthalmic artery aneurysm. Despite an intact visual field, she complained of mild right visual blurriness. Between endovascular and surgical treatments, surgery was favored due to her young age. It was decided to perform the surgery with simultaneous endovascular temporary carotid balloon occlusion. A right pterional craniotomy and intradural anterior clinoidectomy were performed, the balloon was positioned in the petrous carotid, and the distal durai ring was opened exposing the proximal neck. Under temporary proximal carotid balloon occlusion and distal carotid clip occlusion, the aneurysm was fully dissected and clipped. Intraoperative angiogram confirmed complete aneurysm occlusion and patency of the ophthalmic artery. The patient's neurological exam remained unchanged. The video can be found here: http://youtu.be/BIQKTl9bDqA .

  19. Rescue microsurgery with bypass and stent removal following Pipeline treatment of a giant internal carotid artery terminus aneurysm.

    PubMed

    Bowers, Christian A; Taussky, Philip; Park, Min S; Neil, Jayson A; Couldwell, William T

    2015-12-01

    We report the microsurgical rescue and removal of a Pipeline stent embolization of a giant internal carotid artery terminus aneurysm. After the initial placement of a Pipeline Embolization Device (PED), it migrated proximally to the cavernous carotid with the distal end free in the middle of the aneurysm, resulting in only partial aneurysm neck coverage. The patient underwent microsurgical rescue with trapping, bypass, and opening of the aneurysm with PED removal. The vessel remained patent in the proximal segment previously covered by the Pipeline stent. Microsurgical rescue for definitive aneurysm treatment with PED removal can be safe and effective for aneurysms unsuccessfully treated with PED.

  20. 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.

  1. 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).

  2. Stent-Assisted Clip Placement for Complex Internal Carotid Artery Intracranial Aneurysms

    PubMed Central

    Qureshi, Adnan I.; Chughtai, Morad; Khan, Asif A.; Suri, M. Fareed K.; Sherr, Gregory T.

    2016-01-01

    BACKGROUND We report two procedures using a stent-assisted microsurgical clip placement to treat complex intracranial aneurysms originating from supraclinoid segment of the internal carotid artery. CASE DESCRIPTIONS In both procedures, primary clip placement was considered technically difficult due to either complex morphology or inferior protrusion of aneurysm fundus within the interclinoid space. A nitinol self-expanding stent was placed across the neck of the aneurysm either preoperatively or intraoperatively. Obliteration of aneurysm and patency of the artery was confirmed by angiography after clip placement. CONCLUSION Description of an integrated open microsurgical and endovascular approach and review of literature pertaining to considerations for treatment approach are discussed. PMID:26958150

  3. Primary internal carotid artery aneurysm in a 15-year-old male: case report and review of the literature.

    PubMed

    Lopez, Daniel; Sarac, Timur; Lorenz, Robert

    2015-01-01

    Extracranial internal carotid artery aneurysms are a rare entity in the adult population. Very little information is known in the pediatric population. We present a case of a 15-year-old male with an isolated internal carotid artery aneurysm and a review of the literature.

  4. Hybrid endovascular repair of thoracic aortic aneurysm in a patient with Behçet's disease following right to left carotid-carotid bypass grafting.

    PubMed

    Hong, Soonchang; Park, Han Ki; Shim, Won-Heum; Youn, Young-Nam

    2011-03-01

    Endovascular repair of inflammatory aortic aneurysms has been reported as an alternative to open surgical treatment. In selective cases, adjunctive bypass surgery may be required to provide an adequate landing zone. We report a case of endovascular repair of an inflammatory aortic aneurysm in a patient with Behçet's disease using a carotid-carotid bypass graft to provide an adequate landing zone. A 45-yr-old man with a voice change was referred to our hospital with the diagnosis of saccular aneurysm of the distal aortic arch resulting from vasculitis. Computed tomography showed a thoracic aortic aneurysm with thrombosis. Right to left carotid-carotid bypass grafting was performed. After 8 days, the patient underwent an endovascular stent graft placement distal to the origin of the innominate artery. The patient was discharged with medication and without postoperative complications after 5 days. Hybrid endovascular treatment may be suitable a complementary modality for repairing inflammatory aortic aneurysms.

  5. 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

  6. Hemodynamic Changes in Treated Cerebral Aneurysms and Correlations with Long-Term Outcomes

    NASA Astrophysics Data System (ADS)

    McGah, Patrick; Barbour, Michael; Levitt, Michael; Kim, Louis; Aliseda, Alberto

    2014-11-01

    The hemodynamic conditions in patients with cerebral aneurysms undergoing treatment, e.g. flow diverting stents or coil embolization, are investigated via computational simulations. Patient-specific 3D models of the vasculature are derived from rotational angiography. Patient-specific flow and pressure boundary conditions are prescribed utilizing intravascular pressure and velocity measurements. Pre-treatment and immediate post-treatment hemodynamics are studied in eight cases so as to ascertain the effect of the treatment on the intra-aneurysmal flow and wall shear stress. We hypothesize that larger reductions in intra-aneurysmal inflow and wall shear stress after treatment are correlated with an increased likelihood of aneurysmal occlusion and treatment success. Results indicate reductions of the intra-aneurysmal inflow and wall shear stress in all cases. Preliminary clinical six-month follow-up data, assessing if the treatment has been successful, shows that the cases with a persistent aneurysm had a smaller reduction in inflow and wall shear stress magnitude in the immediate post-treatment conditions. This suggests that CFD can be used to quantify a treatment's probability of success by computing the change in pre-and-post-treatment hemodynamics in cerebral aneurysms. NIH-NINDS.

  7. Internal Carotid Artery Blister-Like Aneurysm Caused by Aspergillus – Case Report

    PubMed Central

    Ogawa, Masaki; Sakurai, Keita; Kawaguchi, Takatsune; Naiki-Ito, Aya; Nakagawa, Motoo; Okita, Kenji; Matsukawa, Noriyuki; Shibamoto, Yuta

    2015-01-01

    Summary Background Blister-like aneurysm of the supraclinoid internal carotid artery (ICA) is a well-documented cause of subarachnoid hemorrhage. Generally, this type of aneurysm is associated with various conditions such as hypertension, arteriosclerosis, and ICA dissection. Although Aspergillus is the most common organism causing intracranial fungal aneurysmal formation, there is no report of a blister-like aneurysm caused by Aspergillus infection. Case Report An 83-year-old man received corticosteroid pulse therapy followed by oral steroid therapy for an inflammatory pseudotumor of the clivus. Two months later, the patient was transported to an emergency department due to the diffuse subarachnoid hemorrhage, classified as Fisher group 4. Subsequent 3D computed tomography angiogram revealed a blister-like aneurysm at the superior wall of the left ICA. Six days later, the patient died of subarachnoid hemorrhage caused by the left ICA aneurysm rerupture. Autopsy revealed proliferation of Aspergillus hyphae in the wall of the aneurysm. Notably, that change was present more densely in the inner membrane than in the outer one. Thus, it was considered that Aspergillus hyphae caused infectious aneurysm formation in the left ICA via hematogenous seeding rather than direct invasion. Conclusions The blister-like aneurysm is a rare but important cause of subarachnoid hemorrhage. This case report documents another cause of blister-like aneurysms, that is an infectious aneurysm associated with Aspergillus infection. PMID:25848441

  8. Successful Coil Embolization for a "Three-Hump" Internal Carotid Artery Anterior Wall Aneurysm

    PubMed Central

    Fukushima, Y.; Miyasaka, Y.; Takagi, H.; Kurata, A.; Suzuki, S.; Fujii, K.

    2006-01-01

    Summary We describe an unusually shaped aneurysm arising from the anterior wall of the internal carotid artery (ICA) that was treated successfully with Guglielmi detachable coils (GDCs). A 38-year-old woman presented with sudden onset of headache and was transferred to our hospital. Computed tomography revealed thin subarachnoid hemorrhage in the basal cisterns. Three-dimensional rotational angiography clearly showed a "three-hump" anterior wall aneurysm of the ICA. The two distal humps of the aneurysm were successfully obliterated with GDCs, but the proximal hump was too small to treat by coil embolization. The patient was discharged without neurological deficit. Anterior wall (blisterlike) aneurysms of the ICA have a high risk of rupture due to fragility of the wall. These aneurysms are considered difficult to manage by traditional surgical approaches. Our experience suggests that endovascular GDC embolization is a good alternative treatment modality for patients with such an aneurysm. PMID:20569593

  9. Carotid rete mirabile associated with subarachnoid hemorrhage from intracranial aneurysm: A case report and systematic review

    PubMed Central

    Yamaki, Vitor Nagai; Júnior, Fernando Mendes Paschoal; Piske, Ronie Leo; Teixeira, Manoel Jacobsen; Bor-Seng-Shu, Edson

    2015-01-01

    Carotid rete mirabile (CRM) is a rare physiological vascular network in humans that is most often found in Eastern populations. This paper describes a CRM associated with an aneurysmal subarachnoid hemorrhage (aSAH) and discusses the details of the patient’s treatment. A 28-year-old woman was admitted to our service with clinical signs and symptoms of a spontaneous aSAH. Computed tomography revealed a diffuse and extensive SAH (Fisher group IV), while an angiogram showed an abnormal collateral network in the right carotid system and a hypoplastic aspect to the internal carotid artery (ICA) on the same side. In addition, a saccular aneurysm with a diameter of 9.5 mm was present in the ophthalmic segment of the left ICA. This case is extremely uncommon. To avoid rebleeding in the patient, we successfully treated the patient by clipping the aneurysmal lesion. No procedure was performed for the CRM. PMID:25934776

  10. [A case of accessory middle cerebral artery associated with internal carotid artery aneurysm (author's transl)].

    PubMed

    Munekata, K; Omori, H; Kanazawa, Y; Miyazaki, S; Fukushima, H; Kamata, K

    1979-12-01

    A case of accessory middle cerebral artery associated with internal carotid artery aneurysm was reported. A 50-year-old female was admitted to our hospital with complaints of headache, nausea, vomiting and conciousness disturbance. Lumbar puncture showed bloody CSF. Right carotid angiogram revealed saccular aneurysm of the internal carotid-posterior communicating artery and accessory middle cerebral artery originating from the horizontal portion of the right anterior cerebral artery. No other vascular lesion was observed on other angiograms. Operation was performed 2 days after admission. The neck of the aneurysm was clipped. Postoperative aseptic meningitis was cured by frequent lumbar punctures, and her course was uneventful. The etiological hypothesis of these cerebral vascular anomalies was briefly discussed.

  11. Extracranial Internal Carotid Artery Aneurysms: Report of a Ruptured Case and Review of the Literature

    SciTech Connect

    Siablis, Dimitrios Karnabatidis, Dimitrios; Katsanos, Konstantinos; Mastronikolis, Nikos; Zabakis, Peter; Kraniotis, Pantelis

    2004-08-15

    Aneurysms of the extracranial carotid arteries (ECAA) are extremely rare. Schechter et al. documented 835 cases in the literature up to 1977. One hundred and sixteen cases of ECAA have been documented in the Chinese literature since 1981, suggesting a higher prevalence of carotid aneurysmal disease in China than in the West. Four percent of all peripheral artery aneurysms are reported to be ECAA. Those arising from the internal carotid artery (EICAA) are even more rare. Two recent reviews reported 24 and 25 cases of EICAA during 21 and 17 years, respectively, the majority of them is treated surgically. Our literature review revealed only a few true EICAA managed endovascularly, but none of them with a covered stent. We describe a rare such case of ruptured atherosclerotic EICAA which was treated percutaneously.

  12. Coupling hemodynamics with vascular wall mechanics and mechanobiology to understand intracranial aneurysms

    PubMed Central

    Humphrey, J.D.

    2009-01-01

    Arteries exhibit a remarkable ability to adapt in response to sustained alterations in hemodynamic loading, to heal in response to injuries, and to compensate in response to diverse disease conditions. Nevertheless, such compensatory adaptations are limited and many vascular disorders, if untreated, lead to significant morbidity or mortality. Parallel advances in vascular biology, medical imaging, biomechanics, and computational methods promise to provide increased insight into many arterial diseases, including intracranial aneurysms. In particular, although it may be possible to identify useful clinical correlations between either the blood flow patterns within or the shape of aneurysms and their rupture-potential, our ultimate goal should be to couple studies of hemodynamics with those of wall mechanics and the underlying mechanobiology so that we can understand better the mechanisms by which aneurysms arise, enlarge, and rupture and thereby identify better methods of treatment. This paper presents one such approach to fluid-solid-growth (FSG) modeling of intracranial aneurysms. PMID:20526461

  13. Morphologic and Hemodynamic Analysis in the Patients with Multiple Intracranial Aneurysms: Ruptured versus Unruptured

    PubMed Central

    Jing, Linkai; Fan, Jixing; Wang, Yang; Li, Haiyun; Wang, Shengzhang; Yang, Xinjian; Zhang, Ying

    2015-01-01

    Background and Purpose The authors evaluated the impact of morphologic and hemodynamic factors on multiple intracranial aneurysms and aimed to identify which parameters can be reliable indexes as one aneurysm ruptured, and the others did not. Methods Between June 2011 and May 2014, 69 patients harboring multiple intracranial aneurysms (69 ruptured and 86 unruptured) were analyzed from 3D-digital subtraction angiography (DSA) images and computational fluid dynamics (CFD). Morphologic and hemodynamic parameters were evaluated for significance with respect to rupture. Receiver operating characteristic (ROC) analysis identified area under the curve (AUC) and optimal thresholds separating ruptured from unruptured intracranial aneurysms for each parameter. Significant parameters were examined by binary logistic regression analysis to identify independent discriminators. Results Nine morphologic (size, neck width, surface area, volume, diameter of parent arteries, aspect ratio, size ratio, lateral/bifurcation type and regular/irregular type) and 6 hemodynamic (WSSmean, WSSmin, OSI, LSA, flow stability and flow complexity) parameters achieved statistical significance (p<0.05). Six morphologic (size, surface area, volume, aspect ratio, size ratio and regular/irregular type) and five hemodynamic (WSSmean, WSSmin, LSA, flow stability and flow complexity) parameters had high AUC values (AUC>0.7). By binary logistic regression analysis, large aspect ratio and low WSSmean were the independently significant rupture factors (AUC, 0.924; 95% CI, 0.883–0.965). Conclusions Large aspect ratio and low WSSmean were independently associated with the rupture status of multiple intracranial aneurysms. PMID:26147995

  14. Cerebral hemodynamic changes and electroencephalography during carotid endarterectomy

    SciTech Connect

    Algotsson, L.; Messeter, K.; Rehncrona, S.; Skeidsvoll, H.; Ryding, E. )

    1990-05-01

    Some patients undergoing endarterectomy for occlusive carotid artery disease run a risk of brain ischemia during cross-clamping of the artery. The present study of 15 patients was undertaken to evaluate changes in cerebral blood flow (CBF), as measured with an intravenous (IV) tracer (133Xenon) technique, and to relate CBF changes to changes in the electroencephalogram (EEG). CBF was measured before and after induction of anesthesia, during cross-clamping of the carotid artery, after release of the clamps, and at 24 hours after the operation. All the patients were anesthetized with methohexitone, fentanyl, and nitrous oxide and oxygen. EEG was continuously recorded during the operation. Carotid artery shunts were not used. In 8 patients, cross-clamping of the carotid artery did not influence the EEG. In this group of patients, induction of anesthesia caused a 38% decrease in CBF, which presumably reflects the normal reaction to the anesthetic agent given. There were no further changes in CBF during cross-clamping. In 7 patients, the EEG showed signs of deterioration during the intraoperative vascular occlusion. In these patients, anesthesia did not cause any CBF change, whereas cross-clamping the artery induced a 33% decrease in CBF. In individual patients, the severity of EEG changes correlated with the decrease in CBF. The absence of a change in CBF by anesthesia and a decrease due to cross-clamping of the carotid artery may be explained by the presence of a more advanced cerebrovascular disease and an insufficiency to maintain CBF during cross-clamping.

  15. Comparison of the in vitro hemodynamic performance of new flow diverters for bypass of brain aneurysms.

    PubMed

    Trager, Asher L; Sadasivan, Chander; Lieber, Baruch B

    2012-08-01

    One possible treatment for cerebral aneurysms is a porous tubular structure, similar to a stent, called a flow diverter. A flow diverter can be placed across the neck of a cerebral aneurysm to induce the cessation of flow and initiate the formation of an intra-aneurysmal thrombus. This excludes the aneurysm from the parent artery and returns the flow of blood to normal. Previous flow diverting devices have been analyzed to determine optimal characteristics, such as braiding angle and wire diameter. From this information, a new optimized device was designed to achieve equivalent hemodynamic performance to the previous best device, but with better longitudinal flexibility to preserve physiological arterial configuration. The new device was tested in vitro in an elastomeric replica of the rabbit elastase induced aneurysm model and is now in the process of being tested in vivo. Particle image velocimetry was utilized to determine the velocity field in the plane of symmetry of the model under pulsatile flow conditions. Device hemodynamic performance indices such as the hydrodynamic circulation were evaluated from the velocity fields. Comparison of these indices with the previous best device and a control shows that the significant design changes of the device did not change its hemodynamic attributes (p > 0.05).

  16. Accuracy of Computational Cerebral Aneurysm Hemodynamics Using Patient-Specific Endovascular Measurements

    NASA Astrophysics Data System (ADS)

    McGah, Patrick; Levitt, Michael; Barbour, Michael; Mourad, Pierre; Kim, Louis; Aliseda, Alberto

    2013-11-01

    We study the hemodynamic conditions in patients with cerebral aneurysms through endovascular measurements and computational fluid dynamics. Ten unruptured cerebral aneurysms were clinically assessed by three dimensional rotational angiography and an endovascular guidewire with dual Doppler ultrasound transducer and piezoresistive pressure sensor at multiple peri-aneurysmal locations. These measurements are used to define boundary conditions for flow simulations at and near the aneurysms. The additional in vivo measurements, which were not prescribed in the simulation, are used to assess the accuracy of the simulated flow velocity and pressure. We also performed simulations with stereotypical literature-derived boundary conditions. Simulated velocities using patient-specific boundary conditions showed good agreement with the guidewire measurements, with no systematic bias and a random scatter of about 25%. Simulated velocities using the literature-derived values showed a systematic over-prediction in velocity by 30% with a random scatter of about 40%. Computational hemodynamics using endovascularly-derived patient-specific boundary conditions have the potential to improve treatment predictions as they provide more accurate and precise results of the aneurysmal hemodynamics. Supported by an R03 grant from NIH/NINDS

  17. Computational hemodynamics in cerebral aneurysms: the effects of modeled versus measured boundary conditions.

    PubMed

    Marzo, Alberto; Singh, Pankaj; Larrabide, Ignacio; Radaelli, Alessandro; Coley, Stuart; Gwilliam, Matt; Wilkinson, Iain D; Lawford, Patricia; Reymond, Philippe; Patel, Umang; Frangi, Alejandro; Hose, D Rod

    2011-02-01

    Modeling of flow in intracranial aneurysms (IAs) requires flow information at the model boundaries. In absence of patient-specific measurements, typical or modeled boundary conditions (BCs) are often used. This study investigates the effects of modeled versus patient-specific BCs on modeled hemodynamics within IAs. Computational fluid dynamics (CFD) models of five IAs were reconstructed from three-dimensional rotational angiography (3DRA). BCs were applied using in turn patient-specific phase-contrast-MR (pc-MR) measurements, a 1D-circulation model, and a physiologically coherent method based on local WSS at inlets. The Navier-Stokes equations were solved using the Ansys®-CFX™ software. Wall shear stress (WSS), oscillatory shear index (OSI), and other hemodynamic indices were computed. Differences in the values obtained with the three methods were analyzed using boxplot diagrams. Qualitative similarities were observed in the flow fields obtained with the three approaches. The quantitative comparison showed smaller discrepancies between pc-MR and 1D-model data, than those observed between pc-MR and WSS-scaled data. Discrepancies were reduced when indices were normalized to mean hemodynamic aneurysmal data. The strong similarities observed for the three BCs models suggest that vessel and aneurysm geometry have the strongest influence on aneurysmal hemodynamics. In absence of patient-specific BCs, a distributed circulation model may represent the best option when CFD is used for large cohort studies.

  18. Retreatment of Recurrent Internal Carotid-Posterior Communicating Artery Aneurysm after Coil Embolization.

    PubMed

    Toyota, Shingo; Taki, Takuyu; Wakayama, Akatsuki; Yoshimine, Toshiki

    2015-01-01

    Internal carotid-posterior communicating artery (IC-PC) aneurysms account for more than 20% of all intracranial aneurysms. As a result of the increase in coiling, there has also been an increase in recurrent IC-PC aneurysms after coiling. We present our experience of 10 recurrent IC-PC aneurysms after coiling that were retreated using surgical or endovascular techniques in order to discuss the choice of treatment and the points of clipping without removal of coils. From 2007 to 2014, 10 recurrent IC-PC aneurysms after coiling were retreated. When the previous frames covered the aneurysms all around or almost around except a part of the neck, coiling was chosen. In other cases, clipping was chosen. Clipping was attempted without removal of coils when it was technically feasible. Among the 10 IC-PC aneurysms retreated, 3 were retreated with coiling and 7 were retreated with clipping. In all three cases retreated with coiling, almost complete occlusion was accomplished. In the seven cases retreated with clipping, coil extrusion was observed during surgery in six cases. In most of them, it was necessary to dissect strong adhesions around the coiled aneurysms and to utilize temporary occlusion of the internal carotid artery. In all seven cases, neck clipping was accomplished without the removal of coils. There were no neurological complications in any cases. The management of recurrent lesions of embolized IC-PC aneurysms requires appropriate choice of treatment using both coiling and clipping. Clipping, especially without the removal of coils, plays an important role in safe treatment.

  19. 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

  20. Lattice Boltzmann method simulating hemodynamics in the three-dimensional stenosed and recanalized human carotid bifurcations

    NASA Astrophysics Data System (ADS)

    Kang, XiuYing

    2015-01-01

    By using the lattice Boltzmann method (LBM) pulsatile blood flows were simulated in three-dimensional moderate stenosed and recanalized carotid bifurcations to understand local hemodynamics and its relevance in arterial atherosclerosis formation and progression. The helical flow patterns, secondary flow and wall dynamical pressure spatiotemporal distributions were investigated, which leads to the disturbed shear forces in the carotid artery bifurcations. The wall shear stress distributions indicated by time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), and the relative residence time (RRT) in a cardiac cycle revealed the regions where atherosclerotic plaques are prone to form, extend or rupture. This study also illustrates the point that locally disturbed flow may be considered as an indicator for early atherosclerosis diagnosis. Additionally the present work demonstrates the robust and highly efficient advantages of the LBM for the hemodynamics study of the human blood vessel system.

  1. A Mathematical Model of Intracranial Saccular Aneurysms: Evidence of Hemodynamic Instability

    NASA Astrophysics Data System (ADS)

    Calvisi, Michael; Davis, Stephen; Miksis, Michael

    2010-11-01

    Intracranial saccular aneurysms tend to form at the apex of arterial bifurcations and often assume a nominally spherical shape. In certain cases, the aneurysm growth can become unstable and lead to rupture. While the mechanisms of instability are not well understood, hemodynamics almost certainly play an important role. In this talk, a mathematical model of a saccular aneurysm is presented that describes the shape deformations of an initially spherical membrane interacting with a viscous fluid in the interior. The governing equations are derived from the equations of a thin shell supplemented with a constitutive model that is representative of aneurysmal tissue. Among the key findings are that two families of free vibration modes exist and, for certain values of the membrane properties, one family of nonspherical, axisymmetric modes is unstable to small perturbations. In addition, the presence of a vortical interior flow of sufficient strength can excite resonance of the membrane -- an unstable phenomenon that might cause eventual rupture.

  2. The hemodynamics in intracranial aneurysm ruptured region with active contrast leakage during computed tomography angiography

    NASA Astrophysics Data System (ADS)

    Li, Ming-Lung; Wang, Yi-Chou; Liou, Tong-Miin; Lin, Chao-An

    2014-10-01

    Precise locations of rupture region under contrast agent leakage of five ruptured cerebral artery aneurysms during computed tomography angiography, which is to our knowledge for the first time, were successfully identified among 101 patients. These, together with numerical simulations based on the reconstructed aneurysmal models, were used to analyze hemodynamic parameters of aneurysms under different cardiac cyclic flow rates. For side wall type aneurysms, different inlet flow rates have mild influences on the shear stresses distributions. On the other hand, for branch type aneurysms, the predicted wall shear stress (WSS) correlates strongly with the increase of inlet vessel velocity. The mean and time averaged WSSes at rupture regions are found to be lower than those over the surface of the aneurysms. Also, the levels of the oscillatory shear index (OSI) are higher than the reported threshold value, supporting the assertion that high OSI correlates with rupture of the aneurysm. However, the present results also indicate that OSI level at the rupture region is relatively lower.

  3. The Hemodynamic Effects of Blood Flow-Arterial Wall Interaction on Cerebral Aneurysms

    NASA Astrophysics Data System (ADS)

    Oshima, Marie

    2005-11-01

    Mechanical stresses such as wall shear induced by blood flow play an important role on cardiovascular diseases and cerebral disorders like arterioscleroses and cerebral aneurysm. In order to obtain a better understanding of mechanism of formation, growth, and rupture of cerebral aneurysm, this paper focuses on investigation of cerebral hemodynamics and its effects on aneurismal wall. The paper mainly consists of three parts. Since it is important to obtain the detailed information on the hemodynamic properties in the cerebral circulatory system, the first part discusses a large-scale hemodynamic simulation of the Cerebral Arterial Circle of Willis. The second part presents the simulation and in-vitro experiment of cerebral aneurysm with the consideration of blood flow-arterial wall interaction. Both simulations in the first and the second parts are conducted in a patient specific manner using medical images and also include modeling of boundary conditions to emulate realistic hemodynamic conditions. The present mathematical model, however, includes only macroscopic mechanical functions. Therefore, in the third part, the paper touches upon on future prospects in modeling of microscopic functions such as the effects of endothelial cells and multi physics functions such as physiological effects.

  4. Analysis of intracranial aneurysm wall motion and its effects on hemodynamic patterns

    NASA Astrophysics Data System (ADS)

    Oubel, Estanislao; De Craene, Mathieu; Putman, Christopher M.; Cebral, Juan R.; Frangi, Alejandro F.

    2007-03-01

    Hemodynamics, and in particular Wall Shear Stress (WSS), is thought to play a critical role in the progression and rupture of intracranial aneurysms. Wall motion is related to local biomechanical properties of the aneurysm, which in turn are associated with the amount of damage undergone by the tissue. The underlying hypothesis in this work is that injured regions show differential motion with respect to normal ones, allowing a connection between local wall biomechanics and a potential mechanism of wall injury such as elevated WSS. In a previous work, a novel method was presented combining wall motion estimation using image registration techniques with Computational Fluid Dynamics (CFD) simulations in order to provide realistic intra-aneurysmal flow patterns. It was shown that, when compared to compliant vessels, rigid models tend to overestimate WSS and produce smaller areas of elevated WSS and force concentration, being the observed differences related to the magnitude of the displacements. This work aims to further study the relationships between wall motion, flow patterns and risk of rupture in aneurysms. To this end, four studies containing both 3DRA and DSA studies were analyzed, and an improved version of the method developed previously was applied to cases showing wall motion. A quantification and analysis of the displacement fields and their relationships to flow patterns are presented. This relationship may play an important role in understanding interaction mechanisms between hemodynamics, wall biomechanics, and the effect on aneurysm evolution mechanisms.

  5. CFD and PIV analysis of hemodynamics in a growing intracranial aneurysm.

    PubMed

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

    2012-02-01

    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 images acquired at 1-y intervals. Physical silicone models were constructed from the computed tomography angiography 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.

  6. In-vitro study of the hemodynamics of intracraneal saccular aneurysms

    NASA Astrophysics Data System (ADS)

    Cantón, G.; Varga, C. M.; Lasheras, J. C.; Levy, D. I.

    2001-11-01

    The study of the hemodynamic forces which cause the formation, growth and eventual rupture of aneurysms in the intracranial arteries is of great importance, since cerebral aneurysms are the most common cause of intracranial hemorrhage in adult population. The hemodynamic forces that are believed to contribute to the degeneration of the internal elastic membrane of the arteries are shear stresses, and pressure. The goal of this study is to investigate, through in-vitro models, the effects of blood pressure, cardiac rate, and geometry of the arterial bifurcati on on the distribution of pressure and shear stresses on the walls of saccular aneurysms. A range of arterial geometries is studied while simulating both the pulsatility of the flow and the compliance of the arterial wall. A Particle Image Velocimetry (PIV) system based on a double Nd:Yag pulse laser was used to measure the three dimensional velocity field inside the aneurysm and in the arterial bifurcation. The resulting distribution of pressure and shear stresses are analyzed in the context of the various three-dimensional vortical structures forming in these flows. Furthermore, the effect of placing stents of varying stiffness and porosity on the shear stresses along the aneurysm wall are also investigated.

  7. Bony protuberances on the anterior and posterior clinoid processes lead to traumatic internal carotid artery aneurysm following craniofacial injury.

    PubMed

    Cheong, Jin Hwan; Kim, Jae Min; Kim, Choong Hyun

    2011-01-01

    Traumatic intracranial aneurysms are rare, comprising 1% or less of all cerebral aneurysms. The majority of these aneurysms arise at the skull base or in the distal anterior and middle cerebral arteries or their branches following direct mural injury or acceleration-induced shearing force. We present a 50-year-old patient in whom subarachnoid hemorrhage (SAH) was developed as a result of traumatic aneurysm rupture after a closed craniofacial injury. Through careful evaluation of the three-dimensional computed tomography and conventional angiographies, the possible mechanism of the traumatic internal carotid artery trunk aneurysm is correlated with a hit injury by the bony protuberances on the anterior and posterior clinoid processes. This traumatic aneurysm was successfully obliterated with clipping and wrapping technique. The possibility of a traumatic intracranial aneurysm should be considered when patient with SAH demonstrates bony protuberances on the clinoid process as a traumatic aneurysm may result from mechanical injury by the sharp bony edges.

  8. Numerical analysis of the hemodynamic effect of plaque ulceration in the stenotic carotid artery bifurcation

    NASA Astrophysics Data System (ADS)

    Wong, Emily Y.; Milner, Jaques S.; Steinman, David A.; Poepping, Tamie L.; Holdsworth, David W.

    2009-02-01

    The presence of ulceration in carotid artery plaque is an independent risk factor for thromboembolic stroke. However, the associated pathophysiological mechanisms - in particular the mechanisms related to the local hemodynamics in the carotid artery bifurcation - are not well understood. We investigated the effect of carotid plaque ulceration on the local time-varying three-dimensional flow field using computational fluid dynamics (CFD) models of a stenosed carotid bifurcation geometry, with and without the presence of ulceration. CFD analysis of each model was performed with a spatial finite element discretization of over 150,000 quadratic tetrahedral elements and a temporal discretization of 4800 timesteps per cardiac cycle, to adequately resolve the flow field and pulsatile flow, respectively. Pulsatile flow simulations were iterated for five cardiac cycles to allow for cycle-to-cycle analysis following the damping of initial transients in the solution. Comparison between models revealed differences in flow patterns induced by flow exiting from the region of the ulcer cavity, in particular, to the shape, orientation and helicity of the high velocity jet through the stenosis. The stenotic jet in both models exhibited oscillatory motion, but produced higher levels of phase-ensembled turbulence intensity in the ulcerated model. In addition, enhanced out-of-plane recirculation and helical flow was observed in the ulcerated model. These preliminary results suggest that local fluid behaviour may contribute to the thrombogenic risk associated with plaque ulcerations in the stenotic carotid artery bifurcation.

  9. Influence of Abdominal Aortic Aneurysm Shape on Hemodynamics

    DTIC Science & Technology

    2014-09-19

    know to promote atherosclerosis . 1 Introduction The vascular condition known as abdominal aortic aneurysm (AAA) is a dilatation of at least 1.5 times...flow with oscillat- ing WSS is associated with atherosclerosis (Tarbell et al. 2014). Evidence also suggests that high WSS with sharp spacial gradients

  10. Is aspect ratio sufficient to classify intra-aneurysmal hemodynamics- a parametric approach

    NASA Astrophysics Data System (ADS)

    Durka, Michael; Robertson, Anne

    2013-11-01

    Intracranial aneurysms are a vascular pathology in which a localized bulge is formed in the arterial wall, most often in a saccular shape. It is believed that the blood flow field within the aneurysm plays a critical role in the degradation of the wall. Aneurysm rupture has a high mortality risk. Since only a small fracture of aneurysms rupture, and common treatments have their own risks, it is desirable to identify a useful means of assessing rupture risk. Therefore, numerous groups have endeavored to identify a correlation between rupture risk and sac geometry or flow dynamics. However, no clinically useful parameters have been identified to date. Prior work has suggested that the aspect ratio (sac height/neck) could be useful for risk stratification due to its influence on the sac hemodynamics. In this work, we make of a previously developed parametric model of the aneurysm geometry to evaluate the influence of aspect ratio (sac height/sac neck) on flow dynamics, using computational fluid dynamics. In particular, we assess the influence of aspect ratio on the number of vortices in the aneurysm sac over a wide range of sac geometries. The conclusions obtained for the parametric model are then assessed in 20 clinical cases.

  11. In Vitro Validation of Patient-Specific Hemodynamic Simulations in Coronary Aneurysms Caused by Kawasaki Disease

    PubMed Central

    Kung, Ethan; Kahn, Andrew M.; Burns, Jane C.; Marsden, Alison

    2014-01-01

    To perform experimental validation of computational fluid dynamics (CFD) applied to patient specific coronary aneurysm anatomy of Kawasaki disease. We quantified hemodynamics in a patient-specific coronary artery aneurysm physical phantom under physiologic rest and exercise flow conditions. Using phase contrast MRI (PCMRI), we acquired 3-component flow velocity at two slice locations in the aneurysms. We then performed numerical simulations with the same geometry and inflow conditions, and performed qualitative and quantitative comparisons of velocities between experimental measurements and simulation results. We observed excellent qualitative agreement in flow pattern features. The quantitative spatially and temporally varying differences in velocity between PCMRI and CFD were proportional to the flow velocity. As a result, the percent discrepancy between simulation and experiment was relatively constant regardless of flow velocity variations. Through 1D and 2D quantitative comparisons, we found a 5–17% difference between measured and simulated velocities. Additional analysis assessed wall shear stress differences between deformable and rigid wall simulations. This study demonstrated that CFD produced good qualitative and quantitative predictions of velocities in a realistic coronary aneurysm anatomy under physiological flow conditions. The results provide insights on factors that may influence the level of agreement, and a set of in vitro experimental data that can be used by others to compare against CFD simulation results. The findings of this study increase confidence in the use of CFD for investigating hemodynamics in the specialized anatomy of coronary aneurysms. This provides a basis for future hemodynamics studies in patient-specific models of Kawasaki disease. PMID:25050140

  12. Magnetic Particle Imaging for High Temporal Resolution Assessment of Aneurysm Hemodynamics

    PubMed Central

    Frölich, Andreas; Spallek, Johanna; Forkert, Nils D.; Faizy, Tobias D.; Werner, Franziska; Knopp, Tobias; Krause, Dieter; Fiehler, Jens; Buhk, Jan-Hendrik

    2016-01-01

    Purpose The purpose of this work was to demonstrate the capability of magnetic particle imaging (MPI) to assess the hemodynamics in a realistic 3D aneurysm model obtained by additive manufacturing. MPI was compared with magnetic resonance imaging (MRI) and dynamic digital subtraction angiography (DSA). Materials and Methods The aneurysm model was of saccular morphology (7 mm dome height, 5 mm cross-section, 3–4 mm neck, 3.5 mm parent artery diameter) and connected to a peristaltic pump delivering a physiological flow (250 mL/min) and pulsation rate (70/min). High-resolution (4 h long) 4D phase contrast flow quantification (4D pc-fq) MRI was used to directly assess the hemodynamics of the model. Dynamic MPI, MRI, and DSA were performed with contrast agent injections (3 mL volume in 3 s) through a proximally placed catheter. Results and Discussion 4D pc-fq measurements showed distinct pulsatile flow velocities (20–80 cm/s) as well as lower flow velocities and a vortex inside the aneurysm. All three dynamic methods (MPI, MRI, and DSA) also showed a clear pulsation pattern as well as delayed contrast agent dynamics within the aneurysm, which is most likely caused by the vortex within the aneurysm. Due to the high temporal resolution of MPI and DSA, it was possible to track the contrast agent bolus through the model and to estimate the average flow velocity (about 60 cm/s), which is in accordance with the 4D pc-fq measurements. Conclusions The ionizing radiation free, 4D high resolution MPI method is a very promising tool for imaging and characterization of hemodynamics in human. It carries the possibility of overcoming certain disadvantages of other modalities like considerably lower temporal resolution of dynamic MRI and limited 2D characteristics of DSA. Furthermore, additive manufacturing is the key for translating powerful pre-clinical techniques into the clinic. PMID:27494610

  13. Effect of saccular aneurysm and parent artery morphology on hemodynamics of cerebral bifurcation aneurysms.

    PubMed

    Farnoush, A; Qian, Y; Takao, H; Murayama, Y; Avolio, A

    2012-01-01

    Morphological descriptors of aneurysms have been used to assess aneurysm rupture. This study investigated the relation between the morphological parameters and the flow related parameter of energy loss (EL). Four size indices and one shape index were assessed in idealized middle cerebral artery models with various aneurysm morphologies. Four patient-specific aneurysms (2 ruptured, 2 unruptured) were virtually manipulated by removing the aneurysms from their parent arteries and merging them with the idealized bifurcation models. EL was calculated from the energy difference between inflow and outflow. The results indicate that among size indices, EL is mostly dependent on bottleneck factor and less dependent on the aspect ratio. Results also showed that there is a direct relationship between nonsphericity index (NSI) and EL in manipulated models. No specific correlation was found between EL and NSI in patient-specific models.

  14. Particle-hemodynamics simulations and design options for surgical reconstruction of diseased carotid artery bifurcations.

    PubMed

    Hyun, S; Kleinstreuer, C; Longest, P W; Chen, C

    2004-04-01

    Based on the hypothesis that aggravating hemodynamic factors play a key role in the onset of arterial diseases, the methodology of "virtual prototyping" of branching blood vessels was applied to diseased external carotid artery (ECA) segments. The goals were to understand the underlying particle-hemodynamics and to provide various geometric design options for improved surgical reconstruction based on the minimization of critical hemodynamic wall parameters (HWPs). First, a representative carotid artery bifurcation (CAB) and then CABs with stenosed ECAs, i.e., a distally occluded ECA and an ECA stump, were analyzed based on transient three-dimensional blood flow solutions, employing a user-enhanced commercial finite volume code. Specifically, the HWPs, i.e., oscillatory shear index, wall shear stress angle gradient, near-wall residence time of monocytes, and near-wall helicity angle difference were evaluated to compare the merits of each design option, including a reconstructed near-optimal junction which generates the lowest HWP-values. The results provide physical insight to the biofluid dynamics of branching blood vessels and guide vascular surgeons as well as stent manufacturers towards interventions leading to high sustained patency rates.

  15. Simulation and virtual-reality visualization of blood hemodynamics: the virtual aneurysm

    NASA Astrophysics Data System (ADS)

    Lee, Daren; Valentino, Daniel J.; Duckwiler, Gary R.; Karplus, Walter J.

    2001-05-01

    Intracranial aneurysms are the primary cause of non- traumatic subarachnoid hemorrhage. Difficulties in identifying which aneurysms will grow and rupture arise because the physicians lack important anatomic and hemodynamic information. Through simulation, this data can be captured, but visualization of large simulated data sets becomes cumbersome and tedious, often resulting in visual clutter and ambiguity. TO address these visualization issues, we developed an automated algorithm that decomposes the patterns of 3D, unsteady blood flow into behavioral components to reduce the visual complexity while retaining the structure and information of the original data. Our structural approach analyzes sets of pathlines and groups them together based on spatial locality and shape similarity. Adaptive thresholding is used to refine each component grouping to obtain the largest and tightest cluster. These components can then be visualized individually or superimposed together to formulate a rich understanding of the flow patterns in the aneurysm.

  16. 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.

  17. Spontaneous subarachnoid hemorrhage due to ruptured cavernous internal carotid artery aneurysm after medical prolactinoma treatment.

    PubMed

    Khalsa, Siri Sahib; Hollon, Todd C; Shastri, Ravi; Trobe, Jonathan D; Gemmete, Joseph J; Pandey, Aditya S

    2016-06-08

    Aneurysms of the cavernous segment of the internal carotid artery (ICA) are believed to have a low risk of subarachnoid haemorrhage (SAH), given the confines of the dural rings and the anterior clinoid process. The risk may be greater when the bony and dural protection has been eroded. We report a case of spontaneous SAH from rupture of a cavernous ICA aneurysm in a patient whose large prolactinoma had markedly decreased in size as the result of cabergoline treatment. After passing a balloon test occlusion, the patient underwent successful endovascular vessel deconstruction. This case suggests that an eroding skull base lesion may distort normal anterior cranial base anatomy and allow communication between the cavernous ICA and subarachnoid space. The potential for SAH due to cavernous ICA aneurysm rupture should be recognised in patients with previous pituitary or other skull base lesions adjacent to the cavernous sinus.

  18. Carotid endarterectomy (CE) of the internal carotid artery (ICA) with and without patch angioplasty: comparison of hemodynamical and morphological parameters.

    PubMed

    Hirschl, M; Bernt, R A; Hirschl, M M

    1989-01-01

    The aim of this study was to show, if patch angioplasty or direct closure of the blood vessel following carotid endarterectomy of the ICA resulted in any hemodynamical or morphological differences. Studies were carried out in eighteen and twenty patients, respectively within an average postoperative period of twenty-six month. All patients were examined with continuous-wave Doppler ultrasound, multi-channel pulse Doppler ultrasound and Duplex ultrasonography scanning. Comparing the two groups, differences are predominantly found at or near the site of the endarterectomized segment. Patients who received PTFE (Gore-Tex) patch angioplasty to close the arteriotomy, show in about 50% of all cases a dilatation--pantaloon effect (10)--at the carotid bifurcation (lumina greater than 1.1 cm) when investigating the vessel lumen with duplex sonography. This results in a statistical significant increase in turbulent flow disturbances at the bulb and the origin of the ICA. Furthermore, ICA flow velocity patterns after the endarterectomy point are still within the normal range when compared with patients not receiving a patch plasty, but still significantly elevated. Changes of the vessel wall, as such as intima elevation and intraluminal deposits are more frequently found distal to the endarterectomized segment and do obviously reduce the lumen. However, changes of flow volumina were not quantifiable. Atherosclerotic patients who underwent surgical treatment show as a characteristic finding due to atherosclerosis, a less laminar flow-pattern within the whole extracranial area, when compared with a normal healthy population.

  19. Volume Changes of Experimental Carotid Sidewall Aneurysms Due to Embolization with Liquid Embolic Agents: A Multidetector CT Angiography Study

    SciTech Connect

    Dudeck, O. Okuducu, A. F.; Jordan, O.; Tesmer, K.; Pech, M.; Weigang, E.; Ruefenacht, D. A.; Doelker, E.; Felix, R.

    2006-12-15

    Iodine-containing polyvinyl alcohol polymer (I-PVAL) is a novel precipitating liquid embolic that allows for artifact-free evaluation of CT angiography (CTA). As accurate aneurysm volumetry can be performed with multidetector CTA, we determined volumes of experimental aneurysms before, immediately after, and 4 weeks after embolization of 14 porcine experimental carotid sidewall aneurysms with this liquid embolic. An automated three-dimensional software measurement tool was used for volumetric analysis of volume-rendering CTA data. Furthermore, intra-aneurysmal pressure changes during liquid embolization were measured in four silicone aneurysms and potential polymer volume changes within 4 weeks were assessed in vitro. Liquid embolic injection was performed during temporary balloon occlusion of the aneurysm neck, resulting in a mean occlusion rate of 98.3%. Aneurysms enlarged significantly during embolization by 61.1 {+-} 28.9%, whereas a significant shrinkage of 5.6 {+-} 2.7% was observed within the follow-up period. Histologic analysis revealed an inflammatory foreign body reaction with partial polymer degradation. In silicone aneurysm models, intra-aneurysmal pressure remained unchanged during liquid embolic injection, whereas balloon inflation resulted in a mean pressure increase of 31.2 {+-} 0.7%. No polymer shrinkage was observed in vitro. The aneurysm enlargement noted was presumably due to pressure elevation after balloon inflation, which resulted in dilatation of the weak venous wall of the newly constructed aneurysm-another shortcoming of this experimental aneurysm model. The volume decrease after 4 weeks expressed partial polymer degradation.

  20. Flow diversion in vasculitic intracranial aneurysms? Repair of giant complex cavernous carotid aneurysm in polyarteritis nodosa using Pipeline embolization devices: first reported case.

    PubMed

    Martinez Santos, Jaime; Kaderali, Zul; Spears, Julian; Rubin, Laurence A; Marotta, Thomas R

    2016-07-01

    Intracranial aneurysms in polyarteritis nodosa (PAN) are exceedingly rare lesions with unpredictable behavior that pose real challenges to microsurgical and endovascular interventions owing to their inflammatory nature. We introduce a safe and effective alternative for treating these aneurysms using Pipeline embolization devices (PEDs). A 20-year-old man presented with diplopia, headaches, chronic abdominal pain, and weight loss. Diagnostic evaluations confirmed PAN, including bilateral giant cavernous carotid aneurysms. Cyclophosphamide and steroids achieved significant and sustained clinical improvement, with a decision to follow the aneurysms serially. Seven years later the left unruptured aneurysm enlarged, causing a sudden severe headache and a cavernous sinus syndrome. Treatment of the symptomatic aneurysm was pursued using flow diversion (PED) and the internal carotid artery was successfully reconstructed with a total of four overlapping PEDs. At 6 months follow-up, complete exclusion of the aneurysm was demonstrated, with symptomatic recovery. This is the first description of using a flow-diverting technique in an inflammatory vasculitis. In this case, PEDs not only attained a definitive closure of the aneurysm but also reconstructed the damaged and fragile arterial segment affected with vasculitis.

  1. Flow diversion in vasculitic intracranial aneurysms? Repair of giant complex cavernous carotid aneurysm in polyarteritis nodosa using Pipeline embolization devices: first reported case.

    PubMed

    Santos, Jaime Martinez; Kaderali, Zul; Spears, Julian; Rubin, Laurence A; Marotta, Thomas R

    2015-05-29

    Intracranial aneurysms in polyarteritis nodosa (PAN) are exceedingly rare lesions with unpredictable behavior that pose real challenges to microsurgical and endovascular interventions owing to their inflammatory nature. We introduce a safe and effective alternative for treating these aneurysms using Pipeline embolization devices (PEDs). A 20-year-old man presented with diplopia, headaches, chronic abdominal pain, and weight loss. Diagnostic evaluations confirmed PAN, including bilateral giant cavernous carotid aneurysms. Cyclophosphamide and steroids achieved significant and sustained clinical improvement, with a decision to follow the aneurysms serially. Seven years later the left unruptured aneurysm enlarged, causing a sudden severe headache and a cavernous sinus syndrome. Treatment of the symptomatic aneurysm was pursued using flow diversion (PED) and the internal carotid artery was successfully reconstructed with a total of four overlapping PEDs. At 6 months follow-up, complete exclusion of the aneurysm was demonstrated, with symptomatic recovery. This is the first description of using a flow-diverting technique in an inflammatory vasculitis. In this case, PEDs not only attained a definitive closure of the aneurysm but also reconstructed the damaged and fragile arterial segment affected with vasculitis.

  2. Endovascular Treatment of Internal Carotid and Vertebral Artery Aneurysms Using a Novel Pericardium Covered Stent

    PubMed Central

    Vulev, I.; Klepanec, A.; Bazik, R.; Balazs, T.; Illes, R.; Steno, J.

    2012-01-01

    Summary Intracranial aneurysm is a fairly common (often asymptomatic) condition. Subarachnoid hemorrhage associated with aneurysmal rupture is a potentially lethal event with a mortality rate as high as 50 percent and a high rate of disability among those who survive the initial hemorrhage, such that recently published guidelines support treatment of intracerebral aneurysms. The current treatment options include surgical clipping and endovascular treatment, but these are not without significant problems. Despite the trend toward endovascular treatment the rate of recurrence and complications is high. Current published evidence of the use of covered stent is limited to stents covered with polytetrafluoroethylene. It is now recognized that mammalian extracellular matrix represents an excellent scaffold material suitable for many therapeutic applications and glutaraldehyde treated pericardium has been widely used for many years due to its desirable features such as low immunogenicity and durability. This report describes the first published experience with the Aneugraft Pericardium Covered Stent (ITGI Medical, OR Akiva, Israel) in the treatment of internal carotid and vertebral artery aneurysms in three patients. In all three cases, the implantation of this novel device has resulted in successful closure of aneurysms. PMID:22681731

  3. Endovascular management of a carotid aneurysm into the sphenoid sinus presenting with epistaxis

    PubMed Central

    Gascou, Grégory; Trévillot, Vincent; Bonafé, Alain; Crampette, Louis; Machi, Paolo

    2015-01-01

    Non-traumatic cavernous internal carotid artery (ICA) aneurysms are rare, and favour the occurrence of massive recurrent epistaxis, which is associated with a high mortality rate. We report the case of a 67-year-old woman presenting a ruptured ICA aneurysm extending into the sphenoid sinus, revealed by epistaxis. Selective coil embolization of the aneurysm was performed. Flow-diverter stents were deployed in order to utterly exclude the aneurysm and prevent revascularization. Anti-platelet treatment was provided to lower the risk of in-stent thrombosis. A left frontal hematoma associated with a subarachnoid haemorrhage occurred at day 2. Outcome was favourable with no neurological sequelae, and no clinical recurrence of epistaxis occurred. A 4 months follow-up digital subtraction angiography showed a complete exclusion of the aneurysm. In addition, a magnetic resonance cerebral angiography at 16 months showed stable results. Thus, this two-stage endovascular procedure has proven its effectiveness in preventing epistaxis recurrence while preserving the ICA patency. PMID:26494406

  4. Technical Failure of Giant Supraclinoid Aneurysm after Internal Carotid Artery Occlusion

    PubMed Central

    Liu, Dong; Lv, Ming; Li, Youxiang; Yang, Xinjian; Wu, Zhongxue

    2014-01-01

    Summary We describe three cases of technical failure in patients with giant supraclinoid aneurysm treated with internal carotid artery (ICA) occlusion. Case 1 was a 65-year-old woman who presented with a two-month history of headache accompanied by blurred vision of the left eye. Case 2 was a 43-year-old woman who presented with a six-month history of headache accompanied by blurred vision of the right eye. Case 3 was a 21-year-old man admitted due to headache and blurred vision of the left eye, accompanied by left oculomotor nerve palsy for three months. Cerebral angiography revealed giant supraclinoid aneurysms in these patients. All of them were treated with ICA occlusion. One case had recurrent headache symptoms after the first procedure and was retreated. Two cases suffered from post-procedural intracranial hemorrhagic complications. Before ICA occlusion for giant supraclinoid aneurysm, balloon occlusion test was used to evaluate the collateral anastomosis between the external carotid artery (ECA) and the ICA, and still plays an important role in preventing treatment failure. PMID:25496684

  5. Recurrent Carotid Cavernous Fistula Originating from a Giant Cerebral Aneurysm after Placement of a Covered Stent

    PubMed Central

    Baek, Jung Wook; Lee, Young Seo; Jeong, Young-Gyun; Jeong, Hae Woong; Baek, Jin Wook; Seo, Jung Hwa

    2016-01-01

    We report the case of a recurrent carotid cavernous fistula (CCF) originating from a giant cerebral aneurysm (GCA) after placement of a covered stent. A 47-year-old woman presented with sudden onset of severe headache, and left-sided exophthalmos and ptosis. Cerebral angiography revealed a CCF caused by rupture of a GCA in the cavernous segment of the left internal carotid artery. Two covered stents were placed at the neck of the aneurysm. The neurological symptoms improved at first, but were aggravated in the 6 months following the treatment. Contrast agent endoleak was seen in the distal area of the stent. Even though additional treatments were attempted via an endovascular approach, the CCF could not be cured. However, after trapping the aneurysm using coils and performing superficial temporal artery-middle cerebral artery bypass, the neurological symptoms improved. In cases of recurrent CCF originating from a GCA after placement of a covered stent, it is possible to treat the CCF by endovascular trapping and surgical bypass. PMID:27847780

  6. Supraclinoid Internal Carotid Artery Fenestration Harboring an Unruptured Aneurysm and Another Remote Ruptured Aneurysm: Case Report and Review of the Literature

    PubMed Central

    Park, Seong-Ho

    2012-01-01

    A fenestration of the supraclinoid internal carotid artery (ICA) is a rare congenital condition. We report an aneurysm arising from the proximal end of an ICA fenestration that was treated by endovascular coiling. Three-dimensional rotational angiography of preoperative cerebral angiography provided an understanding of the complex anatomy of the aneurysms associated with the fenestration and may facilitate the clinical decision regarding the treatment option. Endovascular coiling appears to be safe and effective for treating an aneurysm originating from a fenestration on the supraclinoid ICA, which is a difficult lesion to treat using a conventional surgical approach. PMID:23346545

  7. Microscopic anterior clinoidectomy with micro-rongeurs for a superior projecting paraclinoid internal carotid artery aneurysm: a technical note.

    PubMed

    Ota, Takahiro; Mizutani, Tohru

    2013-08-01

    Anterior clinoidectomy is an essential manoeuvre for clipping paraclinoid internal carotid artery (ICA) aneurysms. However, the use of a drill or an ultrasonic bone curette in an anterior clinoidectomy involves a high risk for heat or mechanical injury of the superior projecting paraclinoid aneurysm. We report our technique for microscopic anterior clinoidectomy performed only using a micro-rongeur. The case of a superior projecting paraclinoid ICA aneurysm is presented. The anterior clinoid process was removed with our specially crafted micro-rongeurs, while we observed the extradural and intradural routes under a microscope. The aneurysm was completely clipped without any resulting neurological deficits. This technique can be safely used for paraclinoid ICA aneurysms, especially for superiorly projecting aneurysms.

  8. Use of the Sundt Clip Graft in a Previously Coiled Internal Carotid Artery Blister-Like Aneurysm

    PubMed Central

    Cho, Jae Ik

    2014-01-01

    Owing to the focal wall defect covered with thin fibrous tissues, an aneurysm arising from the dorsal wall of the internal carotid artery (ICA) is difficult to manage either surgically or endovascularly and is often associated with high morbidity and mortality. Unfortunately, the definitive treatment modality of such highly risky aneurysm has not yet been demonstrated. Upon encountering the complex intracranial pathophysiology of such a highly precarious aneurysm, a neurosurgeon would be faced with a challenge to decide on an optimal approach. This is a case of multiple paraclinoid aneurysms including the ICA dorsal wall aneurysm, presented with spontaneous subarachnoid hemorrhage. With respect to treatment, direct clipping with a Sundt graft clip was performed after multiple endovascular interventions had failed. This surgical approach can be a treatment modality for a blood blister-like aneurysm after failed endovascular intervention(s). PMID:25628810

  9. Realistic non-Newtonian viscosity modelling highlights hemodynamic differences between intracranial aneurysms with and without surface blebs.

    PubMed

    Hippelheuser, James E; Lauric, Alexandra; Cohen, Alex D; Malek, Adel M

    2014-11-28

    Most computational fluid dynamic (CFD) simulations of aneurysm hemodynamics assume constant (Newtonian) viscosity, even though blood demonstrates shear-thinning (non-Newtonian) behavior. We sought to evaluate the effect of this simplifying assumption on hemodynamic forces within cerebral aneurysms, especially in regions of low wall shear stress, which are associated with rupture. CFD analysis was performed for both viscosity models using 3D rotational angiography volumes obtained for 26 sidewall aneurysms (12 with blebs, 12 ruptured), and parametric models incorporating blebs at different locations (inflow/outflow zone). Mean and lowest 5% values of time averaged wall shear stress (TAWSS) computed over the dome were compared using Wilcoxon rank-sum test. Newtonian modeling not only resulted in higher aneurysmal TAWSS, specifically in areas of low flow and blebs, but also showed no difference between aneurysms with or without blebs. In contrast, for non-Newtonian analysis, bleb-bearing aneurysms showed significantly lower 5% TAWSS compared to those without (p=0.005), despite no significant difference in mean dome TAWSS (p=0.32). Non-Newtonian modeling also accentuated the differences in dome TAWSS between ruptured and unruptured aneurysms (p<0.001). Parametric models further confirmed that realistic non-Newtonian viscosity resulted in lower bleb TAWSS and higher focal viscosity, especially when located in the outflow zone. The results show that adopting shear-thinning non-Newtonian blood viscosity in CFD simulations of intracranial aneurysms uncovered hemodynamic differences induced by bleb presence on aneurysmal surfaces, and significantly improved discriminant statistics used in risk stratification. These findings underline the possible implications of using a realistic model of blood viscosity in predictive computational hemodynamics.

  10. Endovascular treatment of unruptured aneurysms of cavernous and ophthalmic segment of internal carotid artery with flow diverter device Pipeline

    PubMed Central

    Mounayer, Charbel; Seruga, Tomaz

    2016-01-01

    Abstract Background Intra-arterial treatment of aneurysms by redirecting blood flow is a newer method. The redirection is based on a significantly more densely braided wire stent. The stent wall keeps the blood in the lumen of the stent and slows down the turbulent flow in the aneurysms. Stagnation of blood in the aneurysm sac leads to the formation of thrombus and subsequent exclusion of the aneurysm from the circulation. The aim of the study was to evaluate flow diverter device Pipeline for broad neck and giant aneurysm treatment. Methods Fifteen patients with discovered aneurysm of the internal carotid artery were treated between November 2010 and February 2014. The majority of aneurysms of the internal carotid artery were located intradural at the ophthalmic part of the artery. The patients were treated using a flow diverter device Pipeline, which was placed over the aneurysm neck. Treatment success was assessed clinically and angiographically using O’Kelly Marotta scale. Results Control angiography immediately after the release of the stent showed stagnation of the blood flow in the aneurysm sac. In none of the patients procedural and periprocedural complications were observed. 6 months after the procedure, control CT or MR angiography showed in almost all cases exclusion of the aneurysm from the circulation and normal blood flow in the treated artery. Neurological status six months after the procedure was normal in all patients. Conclusions Treatment of aneurysms with flow diverter Pipeline device is a safe and significantly less time consuming method in comparison with standard techniques. This new method is a promising approach in treatment of broad neck aneurysms. PMID:27904445

  11. A hemodynamic-based dimensionless parameter for predicting rupture of intracranial aneurysms

    NASA Astrophysics Data System (ADS)

    Asgharzadeh, Hafez; Varble, Nicole; Meng, Hui; Borazjani, Iman

    2016-11-01

    Rupture of an intracranial aneurysm (IA) is a disease with high rates of mortality. Given the risk associated with the aneurysm surgery, quantifying the likelihood of aneurysm rupture is essential. There are many risk factors that could be implicated in the rupture of an aneurysm. However, the hemodynamic factors are believed to be the most influential ones. Here, we carry out three-dimensional high resolution simulations on human subjects IAs to test a dimensionless number, denoted as An number, to classify the flow mode. An number is defined as the ratio of the time takes the parent artery flow transports through the expansion region to the time required for vortex formation. Furthermore, we investigate the correlation of IA flow mode and WSS/OSI on the human subject IAs. Finally, we test if An number can distinguish ruptured from unruptured IAs on a database containing 204 human subjects IAs. This work was supported by National Institute Of Health (NIH) Grant R03EB014860 and the Center of Computational Research (CCR) of University at Buffalo.

  12. Epistaxis and pituitary apoplexy due to ruptured internal carotid artery aneurysm embedded within pituitary adenoma

    PubMed Central

    Peng, Zesheng; Tian, Daofeng; Wang, Hongliu; Kong, Derek Kai; Zhang, Shenqi; Liu, Baohui; Deng, Gang; Xu, Zhou; Wu, Liquan; Ji, Baowei; Wang, Long; Cai, Qiang; Li, Mingchang; Wang, Junmin; Zhang, Aimin; Chen, Qianxue

    2015-01-01

    Epistaxis due to ruptured internal carotid artery (ICA) aneurysm embedded within a pituitary adenoma (PA) has seldom been reported in the literature. Here we want to elaborate the incidence, mechanisms, clinical manifestations, and treatment strategy for this condition. The first survived case of a patient with epistaxis and pituitary apoplexy due to ruptured aneurysm embedded within PA was reported and the literature was reviewed. A 53-year-old male patient presented to our institution with sudden onset epistaxis and progressive vision loss. Neurological examination revealed bilateral ptosis and dilated unresponsive pupils. A CT scan showed a large mass in the pituitary fossa with bony erosion. MRI revealed a large pituitary tumor and abnormal signal intensity in the tumor. No aneurysm was noted during the pre-operative MR angiography. Abundant arterial bleeding suddenly occurred during urgent transsphenoidal surgery. Digital subtraction angiography confirmed the presence of a 14 mm unexpected saccular aneurysm of right ICA in the cavernous sinus with the dome protruding into the sella turcica. Balloon test occlusion of the right ICA was undertaken and permanent occlusion was performed. The patient recovered well and received bromocriptine and thyroid hormone replacement therapy during the follow-up period. At 14-month followup, the patient had no neurological deficits, no features of ischaemia relating to the right ICA therapeutic occlusion. Our case indicated that epistaxis and pituitary apoplexy could be due to the rupture of an ICA aneurysm embedded in a PA. Clinical suspicion should remain high when evaluating any case of epistaxis and pituitary apoplexy. Optimal treatment should take into consideration individual features of the tumor, aneurysm, and patient. Making the correct diagnosis as well as identifying an appropriate management strategy is critical in the care of such patients. PMID:26823732

  13. Bilateral carotid and vertebral rete mirabile with vein of Galen aneurysmal malformation: an unreported association

    PubMed Central

    Mondel, Prabath Kumar; Saraf, Rashmi; Limaye, Uday S

    2014-01-01

    Rete mirabile is a fine meshwork of anastomosing vessels that replace the parent artery. A 30-year-old woman complained of slurring of speech, right eye proptosis, recurrent vomiting, and loss of bladder and bowel control, followed by drowsiness lasting 30–40 min, for the past 6 months. On cross sectional imaging and angiography, the patient was found to have a vein of Galen aneurysmal malformation, with bilateral carotid and vertebral rete mirabile. The patient was offered both endovascular and open surgical options but she refused any form of surgical treatment and opted for conservative management. At the 6 month follow-up, she continued to have occasional episodes of headache and vomiting but was otherwise normal. We describe the clinical, cross sectional, and angiographic features of this patient. A comparison with other patients with bilateral carotid and vertebral rete mirabile is also reported. PMID:25414211

  14. [Cerebral vasospasm after coil embolization for unruptured internal carotid artery aneurysm: case report].

    PubMed

    Ogata, Atsushi; Suzuyama, Kenji; Koga, Hisao; Takase, Yukinori; Matsushima, Toshio

    2010-01-01

    A 38-year-old woman was admitted to our hospital with a 3-day history of severe headache associated with some nausea and vomiting. MRI did not show any evidence of subarachnoid hemorrhage, but MRA and CTA showed an aneurysm on the paraclinoid region of the right internal carotid artery. She was successfully treated by coil embolization. MRA taken 7 days after the treatment showed marked vasospam. Fortunately, her therapeutic course was uneventful and she was discharged without any neurological deficits. Vasospasm without subarachnoid hemorrhage is a rare event. Here, we review the literature and discuss potential mechanisms for vasospasm in the absence of subarachnoid hemorrhage.

  15. Mining data from CFD simulation for aneurysm and carotid bifurcation models.

    PubMed

    Miloš, Radović; Dejan, Petrović; Nenad, Filipović

    2011-01-01

    Arterial geometry variability is present both within and across individuals. To analyze the influence of geometric parameters, blood density, dynamic viscosity and blood velocity on wall shear stress (WSS) distribution in the human carotid artery bifurcation and aneurysm, the computer simulations were run to generate the data pertaining to this phenomenon. In our work we evaluate two prediction models for modeling these relationships: neural network model and k-nearest neighbor model. The results revealed that both models have high prediction ability for this prediction task. The achieved results represent progress in assessment of stroke risk for a given patient data in real time.

  16. Finite element modeling of endovascular coiling and flow diversion enables hemodynamic prediction of complex treatment strategies for intracranial aneurysm.

    PubMed

    Damiano, Robert J; Ma, Ding; Xiang, Jianping; Siddiqui, Adnan H; Snyder, Kenneth V; Meng, Hui

    2015-09-18

    Endovascular interventions using coil embolization and flow diversion are becoming the mainstream treatment for intracranial aneurysms (IAs). To help assess the effect of intervention strategies on aneurysm hemodynamics and treatment outcome, we have developed a finite-element-method (FEM)-based technique for coil deployment along with our HiFiVS technique for flow diverter (FD) deployment in patient-specific IAs. We tested four clinical intervention strategies: coiling (1-8 coils), single FD, FD with adjunctive coils (1-8 coils), and overlapping FDs. By evaluating post-treatment hemodynamics using computational fluid dynamics (CFD), we compared the flow-modification performance of these strategies. Results show that a single FD provides more reduction in inflow rate than low packing density (PD) coiling, but less reduction in average velocity inside the aneurysm. Adjunctive coils add no additional reduction of inflow rate beyond a single FD until coil PD exceeds 11%. This suggests that the main role of FDs is to divert inflow, while that of coils is to create stasis in the aneurysm. Overlapping FDs decreases inflow rate, average velocity, and average wall shear stress (WSS) in the aneurysm sac, but adding a third FD produces minimal additional reduction. In conclusion, our FEM-based techniques for virtual coiling and flow diversion enable recapitulation of complex endovascular intervention strategies and detailed hemodynamics to identify hemodynamic factors that affect treatment outcome.

  17. Hemodynamic performance of coil embolization and stentassisted coil embolization treatments: a numerical comparative study based on subject-specific models of cerebral aneurysms

    NASA Astrophysics Data System (ADS)

    Wang, Shengzhang; Zhang, Yisen; Lu, Gang; Yang, Xinjian; Zhang, Xiaolong; Ding, Guanghong

    2011-11-01

    Hemodynamic characteristics such as blood velocity, blood pressure, flow impingement, wall shear stress and oscillatory shear index are considered to play important roles in the initiation, growth, rupture and recurrence of the cerebral aneurysms. Endovascular therapy is widely implemented to treat the cerebral aneurysms by releasing coils into the aneurysm sac for limiting the blood flow to the sac and stent-assisted coil embolization is adopted to occlude the wide-necked or complex aneurysms. Some researchers believe that stents are not only a mechanical device but may act as a biological system and contribute to vessel wall healing. Hemodynamics simulation helps people understand the effect of hemodynamic characteristics on the recurrence of the coiled aneurysm and it also benefits the interventional planning of neurosurgeons. This study constructed the numerical model for a subject-specific ICA aneurysm treated with stent-assisted coil embolization, which combined the coiled model of the aneurysm with a porous stent placement, and simulated the pulsatile blood flow in these aneurysm models. When a stent was placed across the aneurysm orifice in the coiled aneurysm, the high wall shear stress around the distal aneurysm root was reduced more than that of the coiled aneurysm without a stent. The simulated results point to the conclusion that the stent not only protects the parent artery from occlusion due to extension of coils or thrombosis, but may also reduce the recurrence risk of the stent-assisted coiled aneurysm.

  18. Hemodynamic flow modeling through an abdominal aorta aneurysm using data mining tools.

    PubMed

    Filipovic, Nenad; Ivanovic, Milos; Krstajic, Damjan; Kojic, Milos

    2011-03-01

    Geometrical changes of blood vessels, called aneurysm, occur often in humans with possible catastrophic outcome. Then, the blood flow is enormously affected, as well as the blood hemodynamic interaction forces acting on the arterial wall. These forces are the cause of the wall rupture. A mechanical quantity characteristic for the blood-wall interaction is the wall shear stress, which also has direct physiological effects on the endothelial cell behavior. Therefore, it is very important to have an insight into the blood flow and shear stress distribution when an aneurysm is developed in order to help correlating the mechanical conditions with the pathogenesis of pathological changes on the blood vessels. This insight can further help in improving the prevention of cardiovascular diseases evolution. Computational fluid dynamics (CFD) has been used in general as a tool to generate results for the mechanical conditions within blood vessels with and without aneurysms. However, aneurysms are very patient specific and reliable results from CFD analyses can be obtained by a cumbersome and time-consuming process of the computational model generation followed by huge computations. In order to make the CFD analyses efficient and suitable for future everyday clinical practice, we have here employed data mining (DM) techniques. The focus was to combine the CFD and DM methods for the estimation of the wall shear stresses in an abdominal aorta aneurysm (AAA) underprescribed geometrical changes. Additionally, computing on the grid infrastructure was performed to improve efficiency, since thousands of CFD runs were needed for creating machine learning data. We used several DM techniques and found that our DM models provide good prediction of the shear stress at the AAA in comparison with full CFD model results on real patient data.

  19. Asymptomatic aneurysm of the cavernous and supraclinoid internal carotid artery in a patient with Balamuthia mandrillaris encephalitis.

    PubMed

    Orozco, Ludwig D; Khan, Majid A; Fratkin, Jonathan D; Hanigan, William C

    2011-08-01

    This is the first report to our knowledge of the successful treatment of an asymptomatic mycotic aneurysm associated with Balamuthia mandrillaris encephalitis. A 27-year-old male with end-stage renal disease presented with generalized seizures following renal transplantation. MRI demonstrated multiple brain masses and an aneurysm of the cavernous and supraclinoid carotid artery. Autopsy of the donor's brain revealed Balamuthia encephalitis. The patient was placed on an anti-amebic regimen, his condition improved, and 126 days after the kidney transplant, MRI brain showed resolution of the aneurysm and improvement of the enhancing lesions. Balamuthia mandrillaris has been shown to cause a granulomatous encephalitis, with prominent vasculitis. This is the first report to demonstrate the risk of aneurysm formation associated with this infection. Prolonged anti-amebic treatment resulted in resolution of the aneurysm without clinical evidence of subarachnoid hemorrhage.

  20. Blister-like aneurysms of the supraclinoid internal carotid artery: challenging endovascular treatment with stent-assisted coiling.

    PubMed

    Ahn, Jung Yong; Cho, Jun Hyung; Jung, Jin Young; Lee, Byung Hee; Yoon, Pyeong Ho

    2008-09-01

    ''Blister-like'' aneurysms of the supraclinoid segment of the internal carotid artery are usually small and have fragile walls, necessitating special care to prevent rebleeding. These lesions are considered high-risk aneurysms because of the technical difficulties associated with their surgical and endovascular treatment. In this report, we describe the use of stent-assisted, repeated coil embolization in the treatment of a ruptured blister-like aneurysm that experienced rapid growth. Stent-assisted coil embolization is an alternative, but sometimes hazardous, treatment for select blister-like aneurysms. Careful serial follow-up angiography will provide documentation as to the long-term stability of the endovascularly treated blister-like aneurysm described here, but early results are encouraging. Alternatively, placement of telescoped stents or graft-stent devices offers promise for future endovascular therapy.

  1. Does Lower Limb Exercise Worsen Renal Artery Hemodynamics in Patients with Abdominal Aortic Aneurysm?

    PubMed Central

    Zhang, Nan; Xu, Zaipin; Deng, Xiaoyan; Liu, Ming; Liu, Xiao

    2015-01-01

    Renal artery stenosis (RAS) and renal complications emerge in some patients after endovascular aneurysm repair (EVAR) to treat abdominal aorta aneurysm (AAA). The mechanisms for the causes of these problems are not clear. We hypothesized that for EVAR patients, lower limb exercise could negatively influence the physiology of the renal artery and the renal function, by decreasing the blood flow velocity and changing the hemodynamics in the renal arteries. To evaluate this hypothesis, pre- and post-operative models of the abdominal aorta were reconstructed based on CT images. The hemodynamic environment was numerically simulated under rest and lower limb exercise conditions. The results revealed that in the renal arteries, lower limb exercise decreased the wall shear stress (WSS), increased the oscillatory shear index (OSI) and increased the relative residence time (RRT). EVAR further enhanced these effects. Because these parameters are related to artery stenosis and atherosclerosis, this preliminary study concluded that lower limb exercise may increase the potential risk of inducing renal artery stenosis and renal complications for AAA patients. This finding could help elucidate the mechanism of renal artery stenosis and renal complications after EVAR and warn us to reconsider the management and nursing care of AAA patients. PMID:25946196

  2. Severe hyperprolactinemia associated with internal carotid artery aneurysm: differential diagnosis between prolactinoma and hypothalamic-pituitary disconnection.

    PubMed

    Duarte, Felipe Henning Gaia; Machado, Marcio Carlos; Lima, Joilma Rodrigues de; Salgado, Luiz Roberto

    2008-10-01

    Sellar and parasellar masses blocking inhibitory hypothalamic dopaminergic tonus can produce hyperprolactinemia. One of these conditions, seldom reported, is internal carotid artery aneurysm causing pituitary stalk compression and hyperprolactinemia, the majority of which is related to small increases in serum prolactin levels. The aim of this study is to report the case of a patient with an internal carotid aneurysm and severe hiperprolactinemia. A 72 years old female patient, on oncology follow-up for clinically controlled cervical carcinoma, was evaluated due to worsening chronic headaches. During the investigation, computed tomography and magnetic resonance imaging (MRI) showed a sellar mass associated with high prolactin level (1.403 microg/L) that initially was considered a macroprolactinoma, and treated with bromocriptine. However, subsequent pituitary MRI suggested an internal carotid aneurysm, which was confirmed by an angioresonance imaging of cerebral vessels. On low bromocriptine dose (1.25 mg/day), there was a prompt normalization of prolactin levels with a great increase (> 600 microg/L) after withdrawal, which was confirmed several times, suggesting HPD. We report a patient with internal carotid artery aneurysm with severe hyperprolactinemia never reported before in patients with HPD, and the need for a differential diagnosis with macroprolactinomas even considering high prolactin levels.

  3. Three-dimensional hemodynamic design optimization of stents for cerebral aneurysms.

    PubMed

    Lee, Chang-Joon; Srinivas, Karkenahalli; Qian, Yi

    2014-03-01

    Flow-diverting stents occlude aneurysms by diverting the blood flow from entering the aneurysm sac. Their effectiveness is determined by the thrombus formation rate, which depends greatly on stent design. The aim of this study was to provide a general framework for efficient stent design using design optimization methods, with a focus on stent hemodynamics as the starting point. Kriging method was used for completing design optimization. Three different cases of idealized stents were considered, and 40-60 samples from each case were evaluated using computational fluid dynamics. Using maximum velocity and vorticity reduction as objective functions, the optimized designs were identified from the samples. A number of optimized stent designs have been found from optimization, which revealed that a combination of high pore density and thin struts is desired. Additionally, distributing struts near the proximal end of aneurysm neck was found to be effective. The success of the methods and framework devised in this study offers a future possibility of incorporating other disciplines to carry out multidisciplinary design optimization.

  4. Virtual angiography for visualization and validation of computational fluid dynamics models of aneurysm hemodynamics

    NASA Astrophysics Data System (ADS)

    Ford, Matthew D.; Stuhne, Gordan R.; Nikolov, Hristo N.; Lownie, Stephen P.; Holdsworth, David W.; Steinman, David A.

    2005-04-01

    It has recently become possible to simulate aneurysmal blood flow dynamics in a patient-specific manner via the coupling of 3D X-ray angiography and computational fluid dynamics (CFD). Before such image-based CFD models can be used in a predictive capacity, however, it must be shown that they indeed reproduce the in vivo hemodynamic environment. Motivated by the fact that there is currently no technique for measuring complex blood velocity fields in vivo, in this paper we describe how cine X-ray angiograms may be simulated for the purpose of indirectly validating patient-specific CFD models. Mirroring the radiological procedure, a virtual angiogram is constructed by first simulating the time-varying injection of contrast agent into a previously computed patient-specific CFD model. A time-series of images is then constructed by simulating attenuation of X-rays through the simulated 3D contrast-agent flow dynamics. Virtual angiographic images and residence time maps, here derived from an image-based CFD model of a giant aneurysm, are shown to be in excellent agreement with the corresponding clinical images and maps, but only when the interaction between the quasi-steady contrast-agent injection and the pulsatile wash-out are properly accounted for. These virtual angiographic techniques therefore pave the way for validating image-based CFD models against routinely available clinical data, and also provide a means of visualizing complex, 3D blood flow dynamics in a clinically relevant manner. However, they also clearly show how the contrast-agent injection perturbs the normal blood flow dynamics, further highlighting the utility of CFD as a window into the true aneurysmal hemodynamics.

  5. Hemodynamic correlates of late systolic flow velocity augmentation in the carotid artery.

    PubMed

    Heffernan, Kevin S; Lefferts, Wesley K; Augustine, Jacqueline A

    2013-01-01

    Background. The contour of the common carotid artery (CCA) blood flow velocity waveform changes with age; CCA flow velocity increases during late systole, and this may contribute to cerebrovascular disease. Late systolic flow velocity augmentation can be quantified using the flow augmentation index (FAIx). We examined hemodynamic correlates of FAIx to gain insight into determinants of CCA flow patterns. Methods. CCA Doppler ultrasound and wave intensity analysis (WIA) were used to assess regional hemodynamics in 18 young healthy men (age 22 ± 1 years). Forward waves (W 1) and backward waves (negative area, NA) were measured and used to calculate the reflection index (NA/W 1 = RIx). Additional parameters included W 2 which is a forward travelling expansion/decompression wave of myocardial origin that produces suction, CCA single-point pulse wave velocity (PWV) as a measure of arterial stiffness, and CCA pressure augmentation index (AIx). Results. Primary correlates of FAIx included W 2 (r = - 0.52, P < 0.05), logRIx (r = 0.56, P < 0.05), and AIx (r = 0.60, P < 0.05). FAIx was not associated with CCA stiffness (P > 0.05). Conclusions. FAIx is a complex ventricular-vascular coupling parameter that is associated with both increased expansion wave magnitude (increased suction from the left ventricle) and increased pressure from wave reflections.

  6. Effects of carotid hypotension on aortic hemodynamics in the unanesthetized dog.

    PubMed

    Cox, R H; Fronek, A; Peterson, L H

    1975-11-01

    The effects of occlusion of the brachiocephalic artery on aortic hemodynamics were assessed in 12 chronically instrumented dogs in the unanesthetized state. Continuous measurements of ascending aorta pressure and flow were made. In the steady state following occlusion, heart rate increased by 36% and mean arterial pressure by 45%, while cardiac output was unchanged from preocclusion levels. Hydraulic power delivery to the systemic circulation by the left ventricle was increased during occlusion, while the fraction of total power associated with pulsations decreased. Values of peripheral resistance and ascending aorta input impedance were both increased during occlusion. Graded occlusions of the brachiocephalic artery produced graded, monotonic increases in the entire aortic impedance spectrum between 2 and 20 Hz with more sensitive responses occurring with the smaller, submaximal responses. Considered with results of previous studies, these results suggest that activation of smooth muscle in large conduit arteries is also associated with the pressor response which accompanies carotid hypotension and that such activation has a hemodynamically significant effect.

  7. Direct Surgery of Previously Coiled Large Internal Carotid Ophthalmic Aneurysm for the Purpose of Optic Nerve Decompression.

    PubMed

    Kawabata, Shuhei; Toyota, Shingo; Kumagai, Tetsuya; Goto, Tetsu; Mori, Kanji; Taki, Takuyu

    2017-01-01

    Background Progressive visual loss after coil embolization of a large internal carotid ophthalmic aneurysm has been widely reported. It is generally accepted that the primary strategy for this complication should be conservative, including steroid therapy; however, it is not well known as to what approach to take when the conservative therapy is not effective. Case Presentation We report a case of a 55-year-old female presenting with progressive visual loss after the coiling of a ruptured large internal carotid ophthalmic aneurysm. As the conservative therapy had not been effective, we performed neck clipping of the aneurysm with optic canal unroofing, anterior clinoidectomy, and partial removal of the embolized coils for the purpose of optic nerve decompression. After the surgery, the visual symptom was improved markedly. Conclusions It is suggested that direct surgery for the purpose of optic nerve decompression may be one of the options when conservative therapy is not effective for progressive visual disturbance after coil embolization.

  8. Interpositional carotid artery bypass strategies in the surgical management of aneurysms and tumors of the skull base.

    PubMed

    Liu, James K; Couldwell, William T

    2003-03-15

    Cerebral revascularization is an important component in the surgical management of complex skull base tumors and aneurysms. Patients who harbor complex aneurysms that cannot be clipped directly and in whom parent vessel occlusion cannot be tolerated may require cerebrovascular bypass surgery. In cases in which skull base tumors encase the carotid artery (CA) and a resection is desired, a cerebrovascular bypass may be necessary in planned CA occlusion or sacrifice. In this review the authors discuss options for performing high-flow anterograde interposition CA bypass for lesions of the skull base. The authors review three important bypass techniques involving saphenous vein grafts: the cervical-to-petrous internal carotid artery (ICA), petrous-to-supraclinoid ICA, and cervical-to-supraclinoid ICA bypass. These revascularization techniques are important tools in the surgical treatment of complex aneurysms and tumors of the skull base and cavernous sinus.

  9. Paraclinoid carotid artery aneurysms with the dome eroding the anterior clinoid process: preoperative depiction of topography and surgical tactics--two case reports.

    PubMed

    Nagasawa, S; Ogawa, R; Suyama, Y; Ohta, T

    1996-09-01

    A 70-year-old male and a 55-year-old female presented with unruptured aneurysms in the clinoid segment of the carotid artery. Intraoperative rupture during removal of the anterior clinoid process resulted in unintended carotid artery occlusion in the former patient, causing hemispherical infarction and death. However, the aneurysm was successfully clipped due to preoperative recognition of the aneurysmal dome in the clinoid process in the latter. Magnetic resonance angiography and three-dimensional computed tomography angiography source images provide detailed visualization of the topographic anatomy around the paraclinoid aneurysms and are helpful for definite surgical planning.

  10. Embolization of a giant pediatric, posttraumatic, skull base internal carotid artery aneurysm with a liquid embolic agent.

    PubMed

    Reig, Adam S; Simon, Scott; Mericle, Robert A

    2009-11-01

    Many treatments for posttraumatic, skull base aneurysms have been described. Eight months after an all-terrain-vehicle accident, this 12-year-old girl presented with right-side Horner syndrome caused by a 33 x 19-mm internal carotid artery aneurysm at the C-1 level. We chose to treat the aneurysm with a new liquid embolic agent for wide-necked, side-wall aneurysms (Onyx HD 500). We felt this treatment would result in less morbidity than surgery and was less likely to occlude the parent artery than placement of a covered stent, especially in a smaller artery in a pediatric patient. Liquid embolic agents also appear to be associated with a lower chance of recanalization and lower cost compared with stent-assisted coil embolization. After the patient was treated with loading doses of aspirin, clopidogrel bisulfate, and heparin, 99% of the aneurysm was embolized with 9 cc of the liquid embolic agent. There were no complications, and the patient remained neurologically stable. Follow-up angiography revealed durable aneurysm occlusion after 1 year. The cost of Onyx was less than the cost of coils required for coil embolization of similarly sized intracranial aneurysms at our institution. Liquid embolic agents can provide a safe, efficacious, and cost-effective approach to treatment of select giant, posttraumatic, skull base aneurysms in pediatric patients.

  11. Anterior Optic Pathway Compression Due to Internal Carotid Artery Aneurysms: Neurosurgical Management and Outcomes

    PubMed Central

    Park, Wonhyoung; Park, Jung Cheol; Han, Kyunghwa; Ahn, Jae Sung; Kwun, Byung Duk

    2015-01-01

    Background and Purpose Compression of the anterior optic pathway results in visual deficits that can lead to the detection of unruptured aneurysms in the internal carotid artery (ICA). The general types of treatment modalities for aneurysms and visual deficits include surgery and endosaccular coiling. This study retrospectively analyzed and compared the resolution of visual deficits following surgery or endosaccular coiling. Methods We reviewed data on 33 patients with unruptured ICA aneurysms who presented with visual field deficits caused by mass effects over the anterior optic pathway. Statistical analyses were performed to identify the variables associated with the recovery of visual symptoms. Results Eighteen patients underwent aneurysm clipping, 2 underwent bypass surgery with endovascular trapping, and 2 underwent endovascular trapping without bypass surgery (group A). Ten patients received endosaccular coiling (group B). The visual outcomes included the following: in group A, 17 patients (73.9%) demonstrated improvement and 6 patients (26.1%) demonstrated no changes or worse outcomes; in group B, 2 patients (20.0%) demonstrated improvement and 8 patients (80.0%) demonstrated no changes or worse outcomes. Group A was associated with a higher rate of favorable outcome than group B (P = 0.007). According to the multivariate analysis, treatment without endosaccular coiling (group A) was the only variable significantly associated with improvement of visual outcome (P = 0.005; OR = 28.523; 95% CI = 2.683-303.171). Conclusions Treatment modality was the only predictor of improvement in visual deficits. Treatment without endosaccular coiling resulted in visual improvement significantly more often in comparison with endosaccular coiling. PMID:26438000

  12. Hybrid procedure combining clip on wrapping and stent placement for ruptured supraclinoid blood blister-like aneurysm of the internal carotid artery.

    PubMed

    Nagasaki, Hirokazu; Narikiyo, Michihisa; Nagayama, Gota; Nagao, Seiya; Tsuboi, Yoshifumi; Kambayashi, Chisaku

    2017-03-01

    Blood blister-like aneurysms of the supraclinoid portion of the internal carotid artery are rare, fragile, and thin-walled lesions with a higher rate of rebleeding. Our case underwent a hybrid procedure combining direct surgical and endovascular approach.

  13. Numerical analysis of 3D blood flow and common carotid artery hemodynamics in the carotid artery bifurcation with stenosis.

    PubMed

    Antonova, N; Dong, X; Tosheva, P; Kaliviotis, E; Velcheva, I

    2014-01-01

    The results for blood flow in the carotid artery bifurcation on the basis of numerical simulation of Navier-Stokes equations are presented in this study. Four cases of carotid bifurcation are considered: common carotid artery (CCA) bifurcation without stenoses and cases with one, two and three stenoses are also presented. The results are obtained by performing numerical simulations considering one pulse wave period based on the finite volume discretization of Navier-Stokes equations. The structures of the flow around the bifurcation are obtained and the deformation of the pulse wave from common carotid artery (CCA) to the internal carotid artery (ICA) and external carotid artery (ECA) is traced. The axial velocity and wall shear stress (WSS) distribution and contours are presented considering the characteristic time points. The results of the WSS distribution around the bifurcation allow a prediction of the probable sites of stenosis growth.

  14. Subarachnoid Hemorrhage Due to Rupture of an Intracavernous Carotid Artery Aneurysm Coexisting with a Prolactinoma under Cabergoline Treatment

    PubMed Central

    Akutsu, Nobuyuki; Hosoda, Kohkichi; Ohta, Kohei; Tanaka, Hirotomo; Taniguchi, Masaaki; Kohmura, Eiji

    2014-01-01

    We report an unusual case of subarachnoid hemorrhage caused by intraoperative rupture of an intracavernous carotid artery aneurysm coexisting with a prolactinoma. A 58-year-old man presenting with diplopia was found to have a left intracavernous carotid artery aneurysm encased by a suprasellar tumor on magnetic resonance imaging. His serum prolactin level was 5036 ng/mL. Proximal ligation of the left internal carotid artery with a superficial temporal artery to middle cerebral artery anastomosis was scheduled. Because the patient's diplopia had deteriorated, we started him on cabergoline at a dose of 0.25 mg once a week. One month after administration of cabergoline, the diplopia was improved to some extent and serum prolactin was decreased to 290 ng/ml. Six weeks after starting the cabergoline, the patient underwent a left frontotemporal craniotomy to treat the aneurysm. When the dura mater was opened, abnormal brain swelling and obvious subarachnoid hemorrhage were observed. Postoperative computed tomography demonstrated a thick subarachnoid hemorrhage. This case suggests that medical therapy for a pituitary adenoma should be started after treatment for a coexisting intracavernous aneurysm is completed. PMID:25083394

  15. Subarachnoid Hemorrhage Due to Rupture of an Intracavernous Carotid Artery Aneurysm Coexisting with a Prolactinoma under Cabergoline Treatment.

    PubMed

    Akutsu, Nobuyuki; Hosoda, Kohkichi; Ohta, Kohei; Tanaka, Hirotomo; Taniguchi, Masaaki; Kohmura, Eiji

    2014-08-01

    We report an unusual case of subarachnoid hemorrhage caused by intraoperative rupture of an intracavernous carotid artery aneurysm coexisting with a prolactinoma. A 58-year-old man presenting with diplopia was found to have a left intracavernous carotid artery aneurysm encased by a suprasellar tumor on magnetic resonance imaging. His serum prolactin level was 5036 ng/mL. Proximal ligation of the left internal carotid artery with a superficial temporal artery to middle cerebral artery anastomosis was scheduled. Because the patient's diplopia had deteriorated, we started him on cabergoline at a dose of 0.25 mg once a week. One month after administration of cabergoline, the diplopia was improved to some extent and serum prolactin was decreased to 290 ng/ml. Six weeks after starting the cabergoline, the patient underwent a left frontotemporal craniotomy to treat the aneurysm. When the dura mater was opened, abnormal brain swelling and obvious subarachnoid hemorrhage were observed. Postoperative computed tomography demonstrated a thick subarachnoid hemorrhage. This case suggests that medical therapy for a pituitary adenoma should be started after treatment for a coexisting intracavernous aneurysm is completed.

  16. The Numerical Study of the Hemodynamic Characteristics in the Patient-Specific Intracranial Aneurysms before and after Surgery

    PubMed Central

    Byun, Jun Soo; Choi, Sun-Young

    2016-01-01

    The patient-specific pre- and postsurgery cerebral arterial geometries in the study were reconstructed from computed tomography angiography (CTA). Three-dimensional computational fluid dynamics models were used to investigate the hemodynamic phenomena in the cerebral arteries before and after surgery of the aneurysm under realistic conditions. CFD simulations for laminar flow of incompressible Newtonian fluid were conducted by using commercial software, ANSYS v15, with the rigid vascular wall assumption. The study found that the flow patterns with the complex vortical structures inside the aneurysm were similar. We also found that the inflow jet streams were coming strongly in aneurysm sac in the presurgery models, while the flow patterns in postsurgery models were quite different from those in presurgery models. The average wall shear stress after surgery for model 1 was approximately three times greater than that before surgery, while it was about twenty times greater for model 2. The area of low WSS in the daughter saccular aneurysm region in model 2 is associated with aneurysm rupture. Thus the distribution of WSS in aneurysm region provides useful prediction for the risk of aneurysm rupture. PMID:27274764

  17. The Numerical Study of the Hemodynamic Characteristics in the Patient-Specific Intracranial Aneurysms before and after Surgery.

    PubMed

    Byun, Jun Soo; Choi, Sun-Young; Seo, Taewon

    2016-01-01

    The patient-specific pre- and postsurgery cerebral arterial geometries in the study were reconstructed from computed tomography angiography (CTA). Three-dimensional computational fluid dynamics models were used to investigate the hemodynamic phenomena in the cerebral arteries before and after surgery of the aneurysm under realistic conditions. CFD simulations for laminar flow of incompressible Newtonian fluid were conducted by using commercial software, ANSYS v15, with the rigid vascular wall assumption. The study found that the flow patterns with the complex vortical structures inside the aneurysm were similar. We also found that the inflow jet streams were coming strongly in aneurysm sac in the presurgery models, while the flow patterns in postsurgery models were quite different from those in presurgery models. The average wall shear stress after surgery for model 1 was approximately three times greater than that before surgery, while it was about twenty times greater for model 2. The area of low WSS in the daughter saccular aneurysm region in model 2 is associated with aneurysm rupture. Thus the distribution of WSS in aneurysm region provides useful prediction for the risk of aneurysm rupture.

  18. A novel low profile wireless flow sensor to monitor hemodynamic changes in cerebral aneurysm

    NASA Astrophysics Data System (ADS)

    Chen, Yanfei; Jankowitz, Brian T.; Cho, Sung Kwon; Chun, Youngjae

    2015-03-01

    A proof of concept of low-profile flow sensor has been designed, fabricated, and subsequently tested to demonstrate its feasibility for monitoring hemodynamic changes in cerebral aneurysm. The prototype sensor contains three layers, i.e., a thin polyurethane layer was sandwiched between two sputter-deposited thin film nitinol layers (6μm thick). A novel superhydrophilic surface treatment was used to create hemocompatible surface of thin nitinol electrode layers. A finite element model was conducted using ANSYS Workbench 15.0 Static Structural to optimize the dimensions of flow sensor. A computational fluid dynamics calculations were performed using ANSYS Workbench Fluent to assess the flow velocity patterns within the aneurysm sac. We built a test platform with a z-axis translation stage and an S-beam load cell to compare the capacitance changes of the sensors with different parameters during deformation. Both LCR meter and oscilloscope were used to measure the capacitance and the resonant frequency shifts, respectively. The experimental compression tests demonstrated the linear relationship between the capacitance and applied compression force and decreasing the length, width and increasing the thickness improved the sensor sensitivity. The experimentally measured resonant frequency dropped from 12.7MHz to 12.48MHz, indicating a 0.22MHz shift with 200g ( 2N) compression force while the theoretical resonant frequency shifted 0.35MHz with 50g ( 0.5N). Our recent results demonstrated a feasibility of the low-profile flow sensor for monitoring haemodynamics in cerebral aneurysm region, as well as the efficacy of the use of the surface treated thin film nitinol for the low-profile sensor materials.

  19. Hands-On Particle Image Velocimetry Experience for Bioengineering Students Using the Interactive Flowcoach System to Understand Aneurysm Hemodynamics

    NASA Astrophysics Data System (ADS)

    Roszelle, Breigh N.; Okcay, Murat; Oztekin, B. Uygar; Frakes, David H.

    2012-11-01

    The Flowcoach system is a flow visualization and analysis platform from Interactive Flow Studies that uses particle image velocimetry (PIV) and computational fluid dynamics to provide interactive fluid dynamics education. In the spring of 2012, Flowcoach was used at Arizona State University to help teach bioengineering students about biofluid mechanics. A custom insert was made for Flowcoach to model an anatomical aneurysm that could be treated with a high-porosity flow diverting stent. Students performed PIV on the treated aneurysm model in small lab groups using Flowcoach and then wrote reports comparing their results to those from an untreated aneurysm model. The students were surveyed before and after the project and asked to rate their understanding of general biofluid mechanics, as well as experimental fluid mechanics and aneurysmal hemodynamics. Of the 76 students surveyed, 86% indicated an increase in their understanding of biofluid mechanics, and 90% indicated an increase in their understanding of both PIV and cerebral aneurysm hemodynamics. Students' written feedback showed that they felt Flowcoach and the interactive learning experience it provided were both interesting and beneficial to their future careers as engineers.

  20. Delayed pan-hypopituitarism as a complication following endovascular treatment of bilateral internal carotid artery aneurysms. A case report and review.

    PubMed

    Hall, Jonathan; Caputo, Carmela; Chung, Carlos; Holt, Michael; Wang, Yi Yuen

    2015-04-01

    Pan-hypopituitarism has been reported in patients who are subsequently found to have a cerebral aneurysm and there have been reports of pituitary dysfunction immediately following both surgical and endovascular treatment. The authors report a rare case of delayed pan-hypopituitarism following endovascular treatment of bilateral internal carotid artery aneurysms with coil embolisation and flow-diverting stents.

  1. Fluid-Structure Interaction Modeling of Intracranial Aneurysm Hemodynamics: Effects of Different Assumptions

    NASA Astrophysics Data System (ADS)

    Rajabzadeh Oghaz, Hamidreza; Damiano, Robert; Meng, Hui

    2015-11-01

    Intracranial aneurysms (IAs) are pathological outpouchings of cerebral vessels, the progression of which are mediated by complex interactions between the blood flow and vasculature. Image-based computational fluid dynamics (CFD) has been used for decades to investigate IA hemodynamics. However, the commonly adopted simplifying assumptions in CFD (e.g. rigid wall) compromise the simulation accuracy and mask the complex physics involved in IA progression and eventual rupture. Several groups have considered the wall compliance by using fluid-structure interaction (FSI) modeling. However, FSI simulation is highly sensitive to numerical assumptions (e.g. linear-elastic wall material, Newtonian fluid, initial vessel configuration, and constant pressure outlet), the effects of which are poorly understood. In this study, a comprehensive investigation of the sensitivity of FSI simulations in patient-specific IAs is investigated using a multi-stage approach with a varying level of complexity. We start with simulations incorporating several common simplifications: rigid wall, Newtonian fluid, and constant pressure at the outlets, and then we stepwise remove these simplifications until the most comprehensive FSI simulations. Hemodynamic parameters such as wall shear stress and oscillatory shear index are assessed and compared at each stage to better understand the sensitivity of in FSI simulations for IA to model assumptions. Supported by the National Institutes of Health (1R01 NS 091075-01).

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

    PubMed Central

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

    2017-01-01

    Background and Purpose 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). Methods 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. Results 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. Conclusion 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. PMID:28243348

  3. Traumatic aneurysm of the supraclinoid internal carotid artery and an associated carotid-cavernous fistula: vascular reconstruction performed using intravascular implantation of stents and coils. Case report.

    PubMed

    Lee, Chang-Young; Yim, Man-Bin; Kim, Il-Man; Son, Eun-Ik; Kim, Dong-Won

    2004-01-01

    This report documents the treatment of a traumatic aneurysm of the supraclinoid internal carotid artery (ICA) that was associated with a carotid-cavernous fistula (CCF), which appeared following closed head trauma. This life-threatening lesion, which is very rare, required aggressive management achieved using intravascular stents and coils. A 19-year-old man presented with severe traumatic intracerebral and subarachnoid hematoma after he had suffered a severe closed head injury in a motor vehicle accident. Cerebral angiography performed 11 days after the injury demonstrated a traumatic aneurysm and severe narrowing of the right supraclinoid ICA, which was consistent with a dissection-induced stenosis associated with a direct CCF. Both lesions were successfully obliterated with preservation of the parent artery by using stents in conjunction with coils. Follow-up angiography obtained 7 months postoperatively revealed persistent obliteration of the aneurysm and CCF as well as patency of the parent artery. The patient remained asymptomatic during the clinical follow-up period of 14 months. Endovascular treatment involving the use of a stent combined with coils appears to be a feasible, minimally invasive option for treatment of this hard-to-treat lesion.

  4. Multidisciplinary approach to the management of an extracranial internal carotid artery aneurysm approaching the base of the skull in a young patient.

    PubMed

    Pennell, Christopher; Westfall, Scott

    2011-07-01

    Internal carotid artery aneurysms are rare in young patients, especially those without connective tissue disorders or vessel trauma. We present the case of a 29-year-old man who was referred for an asymptomatic pulsatile mass. Computed tomographic angiography identified a true aneurysm between the carotid bifurcation and the base of the skull. This location combined with extensive perineural fibrosis made dissection difficult. Collaboration with an otolaryngologist provided enough distal internal carotid artery exposure for a saphenous vein interposition graft to be placed. Despite initial cranial nerve dysfunction, which later resolved completely, the patient tolerated the procedure well and remains asymptomatic 2 years postoperatively.

  5. Penetration of the Optic Nerve and Falciform Ligament by an Internal Carotid Artery-Ophthalmic Artery Aneurysm: Case Reoport

    PubMed Central

    TAKAGI, Yasushi; MIYAMOTO, Susumu

    2014-01-01

    We report a case of an internal carotid artery (ICA)-ophthalmic artery aneurysm with penetration of the optic nerve. In addition, this case penetrated the falciform ligament, which severely disturbed optic canal unroofing during surgery. This is the first reported case in which penetration of the optic nerve and falciform ligament has been shown. To remove the anterior clinoid process in this case, the ultrasonic bone curette was a useful tool. PMID:24140766

  6. Clinical Outcome of Paraclinoid Internal Carotid Artery Aneurysms After Microsurgical Neck Clipping in Comparison with Endovascular Embolization

    PubMed Central

    Bae, Dong-Hyun; Won, Yu-Deok; Choi, Kyu-Sun; Cheong, Jin-Hwan; Yi, Hyeong-Joong; Kim, Choong-Hyun

    2014-01-01

    Objective Because of the complex anatomical association among vascular, dural, and bony structures, paraclinoid internal carotid artery (ICA) aneurysms remain a major challenge for vascular neurosurgeons. We studied the clinical outcomes of 61 paraclinoid ICA aneurysms after microsurgical clipping in comparison with endovascular coiling. Materials and Methods Between January 2008 and December 2012, we treated 61 paraclinoid ICA aneurysms created by surgical clipping or endovascular coiling. Preoperative neurologic status and postoperative outcome were evaluated using the Glasgow coma scale (GCS) and the modified Rankin scale (mRS). Postoperative hydrocephalus and vasospasm were reviewed using the patients' medical charts. Results Most patients were in good clinical condition before the operations and had good treatment outcomes. Clinical vasospasm was observed after the operation in five patients, and hydrocephalus occurred in six patients. No statistically significant difference regarding aneurysm size, sex, GCS score, H-H grade, and mRS was observed between the surgical clipping group and the endovascular coiling group. In addition, the treatment results and complications did not show statistically significant difference in either group. Conclusion Surgical occlusion of paraclinoid ICA aneurysms is difficult; however, no significant differences were observed in the treatment results or complications when compared with coil embolization. In particular, use of an adequate surgical technique may lead to better outcomes than those for coil embolization in the treatment of large and/or wide-neck paraclinoid ICA aneurysms. PMID:25340024

  7. Surgical strategy to minimize ischemia during trapping/resection of giant extracranial carotid artery aneurysm stratified by collateral evaluation

    PubMed Central

    Hongo, Hiroki; Inoue, Tomohiro; Tamura, Akira; Saito, Isamu

    2017-01-01

    Background: Extracranial carotid artery aneurysm (ECAA) is a rare clinical entity, and no standard treatment strategy has been established for this condition. Methods: Data from three patients who underwent surgical treatment of enlarging giant ECAAs were retrospectively reviewed. Based on the collateral status, as evaluated by preoperative digital subtraction angiography (DSA), surgical strategy was stratified into (1) high flow bypass followed by cervical ICA (internal carotid artery) ligation, when the collateral status was judged as poor/fair or (2) direct cervical repair with patch application after aneurysmal wall resection when the collateral status was judged as robust. Postoperative results were evaluated by magnetic resonance imaging (MRI). Results: Postoperative follow-up (day 0 to 1, as well as midterm at approximately 6 months) confirmed completely trapped aneurysm with successful robust bypass and robust anterograde flow of the reconstructed cervical carotid artery on magnetic resonance angiography with no additional ischemic lesions on diffusion weighted imaging and T2-weighted imaging when compared with preoperative imaging in all three patients. Postoperatively, there was no stroke event during the midterm follow-up at 6 months. Conclusions: Clinical results of ECAAs treated by a surgical strategy stratified based on collateral status, as evaluated by preoperative DSA, were favorable, without postoperative ischemic event, and with satisfactory mid-term MRI results. PMID:28303208

  8. [Dissecting aneurysms at the bases of the brachiocephalic artery and the left common carotid artery due to localized dissection of the aortic arch; report of a case].

    PubMed

    Higashi, Shigeki; Yoshida, Y; Mitsuoka, H

    2007-07-01

    A 43-year-old male lost consciousness immediately after archery practice, and was brought to our hospital by ambulance. Angiography showed dissecting aneurysms at the bases of the brachiocephalic artery and the left common carotid artery, causing compression of these arteries. Under cardiopulmonary bypass with selective cerebral perfusion, the blood supply to these arteries was restored with a bifurcated graft. Surgical specimen showed localized dissection of the aortic arch at the bifurcation to the brachiocephalic artery and the left common carotid artery, with the formation of dissecting aneurysms at the bases of both arteries. The aneurysms were filled with thrombi. In addition to these dissecting aneurysms, there were arterial dissections involving the brachiocephalic artery and the bilateral common carotid arteries. Histopathological examination of the vessel wall showed no evidence of atherosclerosis or vasculitis, and no abnormalities in the arrangement of elastic fibers.

  9. Fungal Internal Carotid Artery Aneurysm Treated by Trapping and High-Flow Bypass: A Case Report and Literature Review

    PubMed Central

    YAMAGUCHI, Junya; KAWABATA, Teppei; MOTOMURA, Ayako; HATANO, Norikazu; SEKI, Yukio

    2016-01-01

    We report a case of unruptured fungal internal carotid artery (ICA) aneurysm and review the pertinent literature. A 79-year-old man presented with decreased visual acuity on the right side, and he was diagnosed with retrobulbar optic neuritis. Medical treatment with steroids resulted in Aspergillus meningoencephalitis spreading to the bottom of bilateral frontal lobes, caused by an intracranial extension of sphenoid sinusitis. Magnetic resonance imaging (MRI) performed 26 days after the start of antifungal therapy showed a denovo right ICA aneurysm projecting anteriorly into the sphenoid sinus. As the aneurysm grew rapidly, it was trapped surgically after establishing a high-flow bypass from the external carotid artery to the middle cerebral artery. The patient’s postoperative course was uneventful. Anti-fungal medication was continued until plasma concentrations of beta-D-glucan decreased to within normal limits. Although fungal ICA aneurysm carries a high mortality rate, early detection and prompt treatment by trapping and high-flow bypass can lead to good clinical outcome. PMID:26804189

  10. Quantification of hemodynamics in abdominal aortic aneurysms during rest and exercise using magnetic resonance imaging and computational fluid dynamics.

    PubMed

    Les, Andrea S; Shadden, Shawn C; Figueroa, C Alberto; Park, Jinha M; Tedesco, Maureen M; Herfkens, Robert J; Dalman, Ronald L; Taylor, Charles A

    2010-04-01

    Abdominal aortic aneurysms (AAAs) affect 5-7% of older Americans. We hypothesize that exercise may slow AAA growth by decreasing inflammatory burden, peripheral resistance, and adverse hemodynamic conditions such as low, oscillatory shear stress. In this study, we use magnetic resonance imaging and computational fluid dynamics to describe hemodynamics in eight AAAs during rest and exercise using patient-specific geometric models, flow waveforms, and pressures as well as appropriately resolved finite-element meshes. We report mean wall shear stress (MWSS) and oscillatory shear index (OSI) at four aortic locations (supraceliac, infrarenal, mid-aneurysm, and suprabifurcation) and turbulent kinetic energy over the entire computational domain on meshes containing more than an order of magnitude more elements than previously reported results (mean: 9.0-million elements; SD: 2.3 M; range: 5.7-12.0 M). MWSS was lowest in the aneurysm during rest 2.5 dyn/cm(2) (SD: 2.1; range: 0.9-6.5), and MWSS increased and OSI decreased at all four locations during exercise. Mild turbulence existed at rest, while moderate aneurysmal turbulence was present during exercise. During both rest and exercise, aortic turbulence was virtually zero superior to the AAA for seven out of eight patients. We postulate that the increased MWSS, decreased OSI, and moderate turbulence present during exercise may attenuate AAA growth.

  11. From bench to bedside: utility of the rabbit elastase aneurysm model in preclinical studies of intracranial aneurysm treatment.

    PubMed

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

    2016-05-01

    Preclinical 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) the 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 preclinical studies using this model are applied in the treatment of intracranial aneurysms in humans. The model has 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 extracranial location of the model 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, but further work is needed to develop aneurysm models that simulate the histopathologic and morphologic characteristics of growing and ruptured aneurysms.

  12. CFD: computational fluid dynamics or confounding factor dissemination? The role of hemodynamics in intracranial aneurysm rupture risk assessment.

    PubMed

    Xiang, J; Tutino, V M; Snyder, K V; Meng, H

    2014-10-01

    Image-based computational fluid dynamics holds a prominent position in the evaluation of intracranial aneurysms, especially as a promising tool to stratify rupture risk. Current computational fluid dynamics findings correlating both high and low wall shear stress with intracranial aneurysm growth and rupture puzzle researchers and clinicians alike. These conflicting findings may stem from inconsistent parameter definitions, small datasets, and intrinsic complexities in intracranial aneurysm growth and rupture. In Part 1 of this 2-part review, we proposed a unifying hypothesis: both high and low wall shear stress drive intracranial aneurysm growth and rupture through mural cell-mediated and inflammatory cell-mediated destructive remodeling pathways, respectively. In the present report, Part 2, we delineate different wall shear stress parameter definitions and survey recent computational fluid dynamics studies, in light of this mechanistic heterogeneity. In the future, we expect that larger datasets, better analyses, and increased understanding of hemodynamic-biologic mechanisms will lead to more accurate predictive models for intracranial aneurysm risk assessment from computational fluid dynamics.

  13. In-stent stenosis in the patient with internal carotid aneurysm after treated by the Willis covered stent

    PubMed Central

    Liu, Lun-Xin; Song, Meng-Yuan; Xie, Xiao-Dong

    2017-01-01

    Abstract In-stent stenosis after treated by Willis covered stent—case reports. Background: Advancements in minimally invasive technology have allowed endovascular reconstruction of internal carotid aneurysm. However, in-stent stenosis is an important and well-characterized complication of stenting after the treatment of internal carotid aneurysm. Case description: We would present 2 patients who were diagnosed with in-stent stenosis after the treatment of Willis covered stent. Case 1: A 57-year-old female with 2-week history of headache and vomiting before admission, whose digital subtraction angiography (DSA) demonstrated left internal carotid C6 aneurysm and showed about 20% stenosis 3 months later since operation in the position where Willis covered stent was deployed. Case 2: A 23-year-old male with skull base fracture, subarachnoid hemorrhage, right femoral fracture for 14 days and epistaxis for 9 hours caused by a car accident, whose DSA demonstrated left internal carotid paracliniod pseudoaneurysm. One year later, the patient went to our center again because he had headache and dizziness for 6 months after the interventional operation. His DSA demonstrated about 80% stenosis in the position where Willis covered stent was deployed. The clinical and radiologic characteristics and the experience in dealing with the stenosis are presented. Conclusions: In-stent stenosis after treated with Willis covered is uncommon, but not rare. Operators should pay more attention to the in-stent stenosis during the period of follow-up observation and monitor P2Y12 Reaction Unit (PRU) in the antiplatelet period, especially for the Willis covered stent. What is more, the treatment for stenosis ought to be carefully considered. PMID:28207524

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

    PubMed Central

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

    2016-01-01

    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. PMID:27869217

  15. 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.

  16. Effects of Reynolds and Womersley Numbers on the Hemodynamics of Intracranial Aneurysms

    PubMed Central

    Asgharzadeh, Hafez

    2016-01-01

    The effects of Reynolds and Womersley numbers on the hemodynamics of two simplified intracranial aneurysms (IAs), that is, sidewall and bifurcation IAs, and a patient-specific IA are investigated using computational fluid dynamics. For this purpose, we carried out three numerical experiments for each IA with various Reynolds (Re = 145.45 to 378.79) and Womersley (Wo = 7.4 to 9.96) numbers. Although the dominant flow feature, which is the vortex ring formation, is similar for all test cases here, the propagation of the vortex ring is controlled by both Re and Wo in both simplified IAs (bifurcation and sidewall) and the patient-specific IA. The location of the vortex ring in all tested IAs is shown to be proportional to Re/Wo2 which is in agreement with empirical formulations for the location of a vortex ring in a tank. In sidewall IAs, the oscillatory shear index is shown to increase with Wo and 1/Re because the vortex reached the distal wall later in the cycle (higher resident time). However, this trend was not observed in the bifurcation IA because the stresses were dominated by particle trapping structures, which were absent at low Re = 151.51 in contrast to higher Re = 378.79. PMID:27847544

  17. [Markedly dilated cervical carotid arteries in a patient with a ruptured aneurysm of the anterior communicating artery: a case report].

    PubMed

    Nakai, H; Kawata, Y; Tomabechi, M; Aizawa, S; Ohgami, S; Yonemasu, Y; Muraoka, S

    1993-04-01

    We reported a case of ruptured aneurysm of the anterior communicating artery with marked dilatation of bilateral cervical carotid arteries. A 38 year old female suffered a subarachnoid hemorrhage. Angiography on admission revealed markedly dilated cervical carotid arteries with smooth lumen and a few segmental areas with mild constrictions in their entire course up to the carotid canals (their maximal sagittal diameters exceeded those of a cervical vertebral body). A saccular aneurysm was also seen at the junction of right A1, A2, and Acom. External carotid arteries were normal in size. Vertebral arteries were not examined because of failures of selective cannulation. The patient was operated upon and trapping of Acom was performed. During the operation, no definite arteriosclerotic changes were identified in the intracranial arteries. Histopathological examination of the surgical specimens revealed marked hyperplasia of the smooth muscle of the tunica media with intact internal elastic lamina both in a superficial temporal artery and a middle meningeal artery. During the operation, pneumothorax developed due to the rupture of bullae in the right lung. Past history of this patient disclosed hypertension noted a few years previously, and frequent severe bruises following minor trauma. Repeated angiography performed three months after the operation disclosed unchanged dilatation of the cervical carotid arteries as well as mild intraluminal irregularities in the proximal one third of the left renal artery. This patient died of pneumonia one year after the operation, but autopsy was not permitted. Possible diagnosis of this patient was discussed, with particular emphasis on fibromuscular dysplasia and Ehlers-Danlos type IV (arterial, ecchymotic, or Sack-Barabas type).(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Direct Surgery of Previously Coiled Large Internal Carotid Ophthalmic Aneurysm for the Purpose of Optic Nerve Decompression

    PubMed Central

    Kawabata, Shuhei; Toyota, Shingo; Kumagai, Tetsuya; Goto, Tetsu; Mori, Kanji; Taki, Takuyu

    2017-01-01

    Background Progressive visual loss after coil embolization of a large internal carotid ophthalmic aneurysm has been widely reported. It is generally accepted that the primary strategy for this complication should be conservative, including steroid therapy; however, it is not well known as to what approach to take when the conservative therapy is not effective. Case Presentation We report a case of a 55-year-old female presenting with progressive visual loss after the coiling of a ruptured large internal carotid ophthalmic aneurysm. As the conservative therapy had not been effective, we performed neck clipping of the aneurysm with optic canal unroofing, anterior clinoidectomy, and partial removal of the embolized coils for the purpose of optic nerve decompression. After the surgery, the visual symptom was improved markedly. Conclusions It is suggested that direct surgery for the purpose of optic nerve decompression may be one of the options when conservative therapy is not effective for progressive visual disturbance after coil embolization. PMID:28229036

  19. Arrested blood flow during false aneurysm formation in the carotid arteries of cattle slaughtered with and without stunning.

    PubMed

    Gregory, N G; Schuster, P; Mirabito, L; Kolesar, R; McManus, T

    2012-02-01

    The time to onset of arrested blood flow and the size of false aneurysms in the severed carotid arteries were assessed in 126 cattle during halal slaughter without stunning. Thirty six cattle (29%) showed early arrest of blood flow. In 6%, both the left and right carotid arteries in the same animal stopped bleeding before 60s had elapsed following the neck cut. The time to early arrested blood flow was on average 21s, and this was accompanied by enlargement with false aneurysms which occluded the arteries. In the arteries which were still bleeding at 60s after the neck was cut the artery size was normal. Based on comparative data from different slaughter premises it appeared that making the cut in the neck at the first cervical vertebra instead of the second to fourth cervical vertebrae reduced the frequency of false aneurysm formation and early arrested blood flow. This was confirmed in a separate controlled trial where 100 cattle were stunned with a captive bolt and the arteries were examined following neck cutting at either the C1 or C3 positions.

  20. A computational simulation of the effect of hybrid treatment for thoracoabdominal aortic aneurysm on the hemodynamics of abdominal aorta

    PubMed Central

    Wen, Jun; Yuan, Ding; Wang, Qingyuan; Hu, Yao; Zhao, Jichun; Zheng, Tinghui; Fan, Yubo

    2016-01-01

    Hybrid visceral-renal debranching procedures with endovascular repair have been proposed as an appealing technique to treat conventional thoracoabdominal aortic aneurysm (TAAA). This approach, however, still remained controversial because of the non-physiological blood flow direction of its retrograde visceral revascularization (RVR) which is generally constructed from the aortic bifurcation or common iliac artery. The current study carried out the numerical simulation to investigate the effect of RVR on the hemodynamics of abdominal aorta. The results indicated that the inflow sites for the RVR have great impact on the hemodynamic performance. When RVR was from the distal aorta, the perfusion to visceral organs were adequate but the flow flux to the iliac artery significantly decreased and a complex disturbed flow field developed at the distal aorta, which endangered the aorta at high risk of aneurysm development. When RVR was from the right iliac artery, the abdominal aorta was not troubled with low WSS or disturbed flow, but the inadequate perfusion to the visceral organs reached up to 40% and low WSS and flow velocity predominated appeared at the right iliac artery and the grafts, which may result in the stenosis in grafts and aneurysm growth on the host iliac artery. PMID:27029949

  1. A computational simulation of the effect of hybrid treatment for thoracoabdominal aortic aneurysm on the hemodynamics of abdominal aorta.

    PubMed

    Wen, Jun; Yuan, Ding; Wang, Qingyuan; Hu, Yao; Zhao, Jichun; Zheng, Tinghui; Fan, Yubo

    2016-03-31

    Hybrid visceral-renal debranching procedures with endovascular repair have been proposed as an appealing technique to treat conventional thoracoabdominal aortic aneurysm (TAAA). This approach, however, still remained controversial because of the non-physiological blood flow direction of its retrograde visceral revascularization (RVR) which is generally constructed from the aortic bifurcation or common iliac artery. The current study carried out the numerical simulation to investigate the effect of RVR on the hemodynamics of abdominal aorta. The results indicated that the inflow sites for the RVR have great impact on the hemodynamic performance. When RVR was from the distal aorta, the perfusion to visceral organs were adequate but the flow flux to the iliac artery significantly decreased and a complex disturbed flow field developed at the distal aorta, which endangered the aorta at high risk of aneurysm development. When RVR was from the right iliac artery, the abdominal aorta was not troubled with low WSS or disturbed flow, but the inadequate perfusion to the visceral organs reached up to 40% and low WSS and flow velocity predominated appeared at the right iliac artery and the grafts, which may result in the stenosis in grafts and aneurysm growth on the host iliac artery.

  2. A computational simulation of the effect of hybrid treatment for thoracoabdominal aortic aneurysm on the hemodynamics of abdominal aorta

    NASA Astrophysics Data System (ADS)

    Wen, Jun; Yuan, Ding; Wang, Qingyuan; Hu, Yao; Zhao, Jichun; Zheng, Tinghui; Fan, Yubo

    2016-03-01

    Hybrid visceral-renal debranching procedures with endovascular repair have been proposed as an appealing technique to treat conventional thoracoabdominal aortic aneurysm (TAAA). This approach, however, still remained controversial because of the non-physiological blood flow direction of its retrograde visceral revascularization (RVR) which is generally constructed from the aortic bifurcation or common iliac artery. The current study carried out the numerical simulation to investigate the effect of RVR on the hemodynamics of abdominal aorta. The results indicated that the inflow sites for the RVR have great impact on the hemodynamic performance. When RVR was from the distal aorta, the perfusion to visceral organs were adequate but the flow flux to the iliac artery significantly decreased and a complex disturbed flow field developed at the distal aorta, which endangered the aorta at high risk of aneurysm development. When RVR was from the right iliac artery, the abdominal aorta was not troubled with low WSS or disturbed flow, but the inadequate perfusion to the visceral organs reached up to 40% and low WSS and flow velocity predominated appeared at the right iliac artery and the grafts, which may result in the stenosis in grafts and aneurysm growth on the host iliac artery.

  3. Transvenous approach for the treatment of direct carotid cavernous fistula following Pipeline embolization of cavernous carotid aneurysm: a report of two cases and review of the literature

    PubMed Central

    Lin, Li-Mei; Colby, Geoffrey P; Jiang, Bowen; Pero, Guglielmo; Boccardi, Edoardo; Coon, Alexander L

    2014-01-01

    Flow diverters are increasingly used for the endovascular treatment of cerebral aneurysms. A rare complication from flow diversion is delayed aneurysm rupture, which can lead to carotid–cavernous fistula (CCF) in the setting of cavernous carotid aneurysms (CCAs). Direct CCFs pose unique management challenges, given the lack of transarterial access to the fistula. We present two cases of direct CCFs following treatment of CCAs with the Pipeline embolization device (PED). Case 1 was a middle-aged patient with a symptomatic 10 mm wide-necked left CCA. Six weeks after PED treatment the patient developed diplopia secondary to direct CCF. Case 2 was a middle-aged patient with a symptomatic 17 mm left CCA treated with PED. One-month follow-up angiography demonstrated a direct CCF. Both patients underwent successful coil embolization of the CCF through a transvenous approach. Direct CCF formation following PED deployment for CCA is a rare complication. Parent vessel sacrifice may be avoided with transvenous occlusion of the fistula. PMID:25073525

  4. Flow diversion and coil embolization may perform best in conjunction for treatment of intracranial aneurysms: a hemodynamic investigation

    NASA Astrophysics Data System (ADS)

    Damiano, Robert; Ma, Ding; Siddiqui, Adnan; Meng, Hui

    2015-11-01

    Coiling and flow diversion is the current standard for treatment of intracranial aneurysms (IAs). Coils deployed into the IA sac trigger its thrombotic occlusion, while flow diverters (FDs) deployed across the IA ostium redirect blood flow and reconstruct the parent vessel. Despite the wide adoption of these interventions, poor treatment outcomes have been reported. Recent clinical reports indicate that IA patients treated with both coils and FDs had better outcomes, compared to individual strategies alone. To better understand the hemodynamic mechanisms underlying coiling and flow diversion, we applied our advanced FEM-based device modeling toolset in conjunction with CFD to investigate 3 clinical strategies: coiling, FD, and FD with adjunctive coiling. Using 3 patient-specific IAs as test beds, we assessed the hemodynamic modifications induced by each strategy. Hemodynamic modifications in inflow rate, velocity, and wall shear stress revealed that coils were most effective at reducing intra-aneurysmal flow, while FD worked best at reducing flow into the IA sac. When coils were combined with FD, these effects appeared to be synergistically enhanced. Our modeling results support clinical observations that flow diversion and coiling may work best in conjunction for treating IAs. Funded by the National Institutes of Health (1R01 NS 091075-01).

  5. Junctional Internal Carotid Artery Aneurysms: The Schrödinger's Cat of Vascular Neurosurgery.

    PubMed

    Carlson, Andrew P; Loveren, Harry R van; Youssef, A Samy; Agazzi, Siviero

    2015-03-01

    Objectives Despite advances in neuroimaging, it is not always definitive whether a paraclinoid aneurysm is intradural or entirely extradural. We illustrate the potential use of surgical exploration in these aneurysms that we refer to as "junctional" aneurysms. Methods Retrospective review of eight patients with unruptured aneurysms who underwent a planned surgical exploration of a junctional aneurysm. Results Of the eight patients, three underwent exploration of the aneurysm during surgery for a different aneurysm. All three of these were found to be extradural. Five patients underwent a craniotomy for the exclusive purpose of clarifying the location of the aneurysm. Two of these cases were found to be intradural and were clipped. Two cases were found to be extradural. In one patient, the initially extradural aneurysm was converted into an intradural aneurysm during removal of the anterior clinoid process, necessitating surgical clipping. One transient third nerve palsy was observed. Discussion Until further progress in neuroimaging allows clinicians to determine unequivocally the exact anatomical location of a paraclinoid aneurysm, we advocate the use of the term junctional aneurysm to reflect the clinical uncertainty inherent in management decisions made regarding these aneurysms. We have illustrated a strategy of surgical exploration in select patients.

  6. Junctional Internal Carotid Artery Aneurysms: The Schrödinger's Cat of Vascular Neurosurgery

    PubMed Central

    Carlson, Andrew P.; Loveren, Harry R. van; Youssef, A. Samy; Agazzi, Siviero

    2014-01-01

    Objectives Despite advances in neuroimaging, it is not always definitive whether a paraclinoid aneurysm is intradural or entirely extradural. We illustrate the potential use of surgical exploration in these aneurysms that we refer to as “junctional” aneurysms. Methods Retrospective review of eight patients with unruptured aneurysms who underwent a planned surgical exploration of a junctional aneurysm. Results Of the eight patients, three underwent exploration of the aneurysm during surgery for a different aneurysm. All three of these were found to be extradural. Five patients underwent a craniotomy for the exclusive purpose of clarifying the location of the aneurysm. Two of these cases were found to be intradural and were clipped. Two cases were found to be extradural. In one patient, the initially extradural aneurysm was converted into an intradural aneurysm during removal of the anterior clinoid process, necessitating surgical clipping. One transient third nerve palsy was observed. Discussion Until further progress in neuroimaging allows clinicians to determine unequivocally the exact anatomical location of a paraclinoid aneurysm, we advocate the use of the term junctional aneurysm to reflect the clinical uncertainty inherent in management decisions made regarding these aneurysms. We have illustrated a strategy of surgical exploration in select patients. PMID:25844299

  7. Effect of Turbulence on the Temporal Variation of Hemodynamic Stresses in Aneurysm Model under Resting and Exercise Conditions

    NASA Astrophysics Data System (ADS)

    Khanafer, Khalil

    2005-11-01

    A numerical model is developed to analyze pulsatile turbulent flow in axisymmetric abdominal aortic aneurysm models (AAM) using realistic physiological resting and exercise waveforms. The transport equations are solved using the finite element formulation based on the Galerkin method of weighted residuals. The κ-ɛ model is used in this work to simulate turbulence characteristics of the convective flow by incorporating Boussinesq eddy-viscosity model. A number of interesting features of the flow field resulting from using realistic physiological waveforms are obtained for various pertinent parameters. Such parameters include Reynolds number, size of aneurysm, flexibility of aneurysm's wall, and the propagation of pressure and flow waves through AAM. The effect of non-Newtonian behavior of blood on hemodynamic stresses and compared with Newtonian behavior through AAM is investigated in the present study. The results of the present work illustrate that maximum turbulent shear stress occurs at the distal end of the AAA model. Furthermore, turbulence is found to have a significant effect on the pressure distribution along AAA wall for both physiological waveforms. This work paves the road for researchers in the area of AAA risk rupture to improve their understanding on the mechanics of aneurysm rupture enhanced by increased flow turbulence.

  8. Unruptured internal carotid-posterior communicating artery aneurysm splitting the oculomotor nerve: a case report and literature review.

    PubMed

    Toyota, Shingo; Taki, Takuyu; Wakayama, Akatsuki; Yoshimine, Toshiki

    2014-08-01

    Objective To report a rare case of unruptured internal carotid-posterior communicating artery (IC-PC) aneurysm splitting the oculomotor nerve treated by clipping and to review the previously published cases. Case Presentation A 42-year-old man suddenly presented with left oculomotor paresis. Three-dimensional digital subtraction angiography (3D DSA) demonstrated a left IC-PC aneurysm with a bulging part. During surgery, it was confirmed that the bulging part split the oculomotor nerve. After the fenestrated oculomotor nerve was dissected from the bulging part with a careful microsurgical technique, neck clipping was performed. After the operation, the symptoms of oculomotor nerve paresis disappeared within 2 weeks. Conclusions We must keep in mind the possibility of an anomaly of the oculomotor nerve, including fenestration, and careful observation and manipulation should be performed to preserve the nerve function during surgery, even though it is very rare.

  9. Microsurgical Relations between Internal Carotid Artery–Posterior Communicating Artery (ICA-PComA) Segment Aneurysms and Skull Base: An Anatomoclinical Study

    PubMed Central

    González-Darder, José M.; Quilis-Quesada, Vicent; Talamantes-Escribá, Fernando; Botella-Maciá, Laura; Verdú-López, Francisco

    2012-01-01

    Purpose The study of the clinical, anatomic, imaging, and microsurgical characteristics of the aneurysms of the internal carotid-posterior communicating artery (ICA-PComA) segment and their relationships with the skull base structures. Methods The anatomic relationships of PComA with neurovascular elements and skull base structures were studied in cadavers. The clinical, imaging, and microsurgical findings of 84 microsurgically treated ICA-PComA aneurysms compiled in a prospective database were reviewed. Results The most important anatomic relations of the PComA and ICA-PComA aneurysms are with the oculomotor nerve around the oculomotor triangle that forms the roof of the cavernous sinus. Aneurysms of the ICA-PComA are classified according to the orientation of the aneurysmal sac in infratentorial, supratentorial, and tentorial. Infratentorial aneurysms frequently present with subarachnoid hemorrhage (SAH) and oculomotor nerve paralysis. They have relations with skull base structures that often make it necessary to totally or partially resect the anterior clinoid process (6.7%) or anterior petroclinoid dural fold (15%). Supratentorial aneurysms course with SAH and without oculomotor nerve involvement, but they often are associated with intracranial hematoma. Conclusion ICA-PComA aneurysms have complex anatomic relations. The orientation of the aneurysmal fundus induces relevant differences in the anatomic relations, clinical presentation, and microsurgical approach to ICA-PComA aneurysms. PMID:24083126

  10. Understanding the role of hemodynamics in the initiation, progression, rupture, and treatment outcome of cerebral aneurysm from medical image-based computational studies.

    PubMed

    Castro, Marcelo A

    2013-01-01

    About a decade ago, the first image-based computational hemodynamic studies of cerebral aneurysms were presented. Their potential for clinical applications was the result of a right combination of medical image processing, vascular reconstruction, and grid generation techniques used to reconstruct personalized domains for computational fluid and solid dynamics solvers and data analysis and visualization techniques. A considerable number of studies have captivated the attention of clinicians, neurosurgeons, and neuroradiologists, who realized the ability of those tools to help in understanding the role played by hemodynamics in the natural history and management of intracranial aneurysms. This paper intends to summarize the most relevant results in the field reported during the last years.

  11. Investigation of hemodynamics in the development of dissecting aneurysm within patient-specific dissecting aneurismal aortas using computational fluid dynamics (CFD) simulations.

    PubMed

    Tse, Kwong Ming; Chiu, Peixuan; Lee, Heow Pueh; Ho, Pei

    2011-03-15

    Aortic dissecting aneurysm is one of the most catastrophic cardiovascular emergencies that carries high mortality. It was pointed out from clinical observations that the aneurysm development is likely to be related to the hemodynamics condition of the dissected aorta. In order to gain more insight on the formation and progression of dissecting aneurysm, hemodynamic parameters including flow pattern, velocity distribution, aortic wall pressure and shear stress, which are difficult to measure in vivo, are evaluated using numerical simulations. Pulsatile blood flow in patient-specific dissecting aneurismal aortas before and after the formation of lumenal aneurysm (pre-aneurysm and post-aneurysm) is investigated by computational fluid dynamics (CFD) simulations. Realistic time-dependent boundary conditions are prescribed at various arteries of the complete aorta models. This study suggests the helical development of false lumen around true lumen may be related to the helical nature of hemodynamic flow in aorta. Narrowing of the aorta is responsible for the massive recirculation in the poststenosis region in the lumenal aneurysm development. High pressure difference of 0.21 kPa between true and false lumens in the pre-aneurismal aorta infers the possible lumenal aneurysm site in the descending aorta. It is also found that relatively high time-averaged wall shear stress (in the range of 4-8 kPa) may be associated with tear initiation and propagation. CFD modeling assists in medical planning by providing blood flow patterns, wall pressure and wall shear stress. This helps to understand various phenomena in the development of dissecting aneurysm.

  12. Using vortex corelines to analyze the hemodynamics of patient specific cerebral aneurysm models

    NASA Astrophysics Data System (ADS)

    Byrne, Greg; Mut, Fernando; Cebral, Juan

    2012-02-01

    We construct one-dimensional sets known as vortex corelines for computational fluid dynamic (CFD) simulations of blood flow in patient specific cerebral aneurysm models. These sets identify centers of swirling blood flow that may play an important role in the biological mechanisms causing aneurysm growth, rupture, and thrombosis. We highlight three specific applications in which vortex corelines are used to assess flow complexity and stability in cerebral aneurysms, validate numerical models against PIV-based experimental data, and analyze the effects of flow diverting devices used to treat intracranial aneurysms.

  13. Impact of Endovascular Technique on Fluoroscopy Usage: Stent-Assisted Coiling versus Flow Diversion for Paraclinoid Internal Carotid Artery Aneurysms

    PubMed Central

    Miller, Timothy R; Jindal, Gaurav; Krejza, Jaroslaw; Gandhi, Dheeraj

    2014-01-01

    Summary Flow diversion is increasingly being utilized for the treatment of internal carotid artery (ICA) aneurysms. The purpose of this study was to evaluate the impact of endovascular technique--flow diversion versus stent-assisted coiling (SAC) on fluoroscopy time in patients treated for wide-neck paraclinoid ICA aneurysms. A retrospective review identified the 20 most recent consecutive patients treated for wide-neck paraclinoid ICA aneurysms by flow diversion and SAC respectively. Fluoroscopy time, cumulative dose area-product (DAP), contrast usage, intra-procedural complications, and total procedure time were collected and compared between the two treatment techniques. Treatment groups were comparable in terms of demographics, contrast usage, and clinical and angiographic outcomes. Flow diversion was associated with a significant reduction in fluoroscopy time (52.0 minutes versus 77.4 minutes), and demonstrated a strong trend towards shorter total procedure time (172 minutes versus 202 minutes). Average patient radiation exposure as measured by DAP was lower in the flow diversion group, 13225 mGyxcm2 versus 15124 mGyxcm2, although this finding was not statistically significant. There was no significant difference in contrast usage between the two groups, 152 ml and 159 (flow diversion and SAC respectively). The rate of complete aneurysm occlusion was higher in the flow diversion group (80% versus 60%). Endovascular treatment of paraclinoid ICA aneurysms with flow diversion is associated with shorter fluoroscopy times compared to stent-assisted coiling. There is also a likely reduction in overall procedure time. These results should be considered when recommending a treatment course for patients with such lesions. PMID:25489897

  14. Ruptured aneurysm at the cortical segment of the distal posterior inferior cerebellar artery associated with hemodynamic stress after basilar artery occlusion

    PubMed Central

    Marutani, Akiko; Nakagawa, Ichiro; Park, Hun Soo; Tamura, Kentaro; Motoyama, Yasushi; Nakase, Hiroyuki

    2016-01-01

    Background: A distal posterior inferior cerebellar artery (PICA) de novo aneurysm at the cortical segment after atherosclerotic basilar artery occlusion is extremely rare. Here, we report the case of a ruptured distal PICA de novo aneurysm 8 years after basilar artery occlusion. Case Description: A 75-year-old man experienced sudden disturbance of consciousness; computed tomography demonstrated cerebellar and subarachnoid hemorrhage due to a ruptured distal PICA aneurysm. Neck clipping of the aneurysm prevented re-rupture initially, and superficial temporal artery-superior cerebellar artery (STA-SCA) bypass was performed 3 months after admission. Postoperative angiography confirmed patency of the bypass, and the patient was discharged without any new neurological deficits. Conclusion: This report describes a case of de novo development of a saccular distal PICA aneurysm after atherosclerotic basilar artery occlusion. We believe that increased hemodynamic stress at the PICA might have contributed to the occurrence and rupture of the aneurysm. STA-SCA bypass, introduced in the territory of the cerebellar hemisphere, reduces hemodynamic stress, which would prevent the occurrence of de novo aneurysm and recurrent bleeding. PMID:28144485

  15. Hemodynamic Changes Caused by Flow Diverters in Rabbit Aneurysm Models: Comparison of Virtual and Realistic FD Deployments Based on Micro-CT Reconstruction.

    PubMed

    Xu, Jinyu; Deng, Benqiang; 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.

  16. Towards the evaluation of the pathological state of ascending thoracic aneurysms: integration of in-vivo measurements and hemodynamic simulations

    NASA Astrophysics Data System (ADS)

    Boccadifuoco, Alessandro; Mariotti, Alessandro; Celi, Simona; Martini, Nicola; Salvetti, Maria Vittoria

    2016-11-01

    Ascending thoracic aortic aneurysms are cardiovascular diseases consisting in a dilation of the ascending thoracic aorta. Since indicating a weakness of the arterial wall, they can lead to major complications with significant mortality rate. Clinical decisions about surgery are currently based on the maximum aortic diameter, but this single index does not seem a reliable indicator of the pathological state of the aorta. Numerical simulations of the blood flow inside the aneurysm may give supplementary information by quantifying important indices that are difficult to be measured, like the wall shear stress. Our aim is to develop an efficient platform in which in-vivo measurements are used to perform the hemodynamic simulations on a patient-specific basis. In particular, we used real geometries of thoracic aorta and focused on the use of clinical information to impose accurate boundary conditions at the inlet/outlets of the computational model. Stochastic analysis was also performed, to evaluate how uncertainties in the boundary parameters affect the main hemodynamic indicators, by considering both rigid and deformable walls. Stochastic calibration of numerical parameters against clinical data is in progress and results will be possibly shown.

  17. Comparison Between Balloon-Assisted and Stent-Assisted Technique for Treatment of Unruptured Internal Carotid Artery Aneurysms

    PubMed Central

    Park, Keun Young; Kim, Dong Joon

    2016-01-01

    Purpose To compare clinical and angiographic outcomes between balloon-assisted (BAC) and stent-assisted coiling for internal carotid artery unruptured aneurysms (ICA-UA). Materials and Methods A total of 227 ICA-UA in 190 patients were treated with BAC (120 patients, 141 ICA-UA) or SAC (70 patients, 86 ICA-UA. We compared characteristics of patients and ICA-UA, and clinical and angiographic outcomes between groups. Results Aneurysm size and neck diameter were greater for SAC than in BAC, but aneurysm volume and coil packing density were not different between groups. Immediate angiographic occlusion grade was better for BAC than for SAC. Periprocedural thromboembolic events were more frequent during SAC (11.6%) than BAC (2.4%) per aneurysm, but hemorrhagic events were the opposite (2.4% for BAC and none for SAC per aneurysm) (p < 0.05). At discharge, treatment-related morbi-mortality rates were 1.6% for BAC and 1.4% per patient for SAC. At clinical follow-up (BAC, 118 patients [98.3%] for a mean of 48.4 months; SAC, 69 patients [98.6%], for a mean of 37.4 months), 1 additional treatment-related infarction occurred during SAC, resulting in a modified Rankin scale score of 4. Thus, overall treatment-related morbi-mortality rates were 1.7% in BAC and 2.9% in SAC. At imaging follow-up (BAC, 135 aneurysms [95.7%] for 28.3 months; SAC, 81 aneurysms [94.1%] for 23.9 months), BAC and SAC showed stable or improved occlusion in 94.1% and 95.0%, minor recurrence in 4.4% and 2.5%, and major recurrence in 1.5% and 2.5%, respectively. Conclusion Both BAC and SAC were safe and effective techniques for ICA-UA. There were no differences in morbi-mortality and recurrence rates between groups. PMID:27621946

  18. Controlateral cavernous syndrome, brainstem congestion and posterior fossa venous thrombosis with cerebellar hematoma related to a ruptured intracavernous carotid artery aneurysm.

    PubMed

    Aldea, Sorin; Guedin, Pierre; Roccatagliata, Luca; Boulin, Anne; Auliac, Stéphanie; Dupuy, Michel; Cerf, Charles; Gaillard, Stéphan; Rodesch, Georges

    2011-06-01

    Intracavernous carotid artery aneurysms (ICCAs) are rarely associated with life-threatening complications. We describe a 55-year-old woman who, after the rupture of an intracavernous carotid artery aneurysm, presented with a contralateral cavernous sinus syndrome and severe posterior fossa and spinal cord symptoms. Following parent artery occlusion, thrombosis of the posterior fossa and spinal cord veins caused a progressive worsening of the neurological status to a "locked-in" state. The patient fully recovered with anticoagulation therapy. Comprehension of the pathophysiological mechanism associated with the rupture of ICCA and early diagnosis of the related symptoms are essential in order to plan a correct treatment that includes the management of the aneurysm rupture and of possible complications related to venous thrombosis.

  19. 4D flow preliminary investigation of a direct carotid cavernous fistula due to a ruptured intracavernous aneurysm

    PubMed Central

    Nakagawa, Shunsuke; Murai, Yasuo; Wada, Takeshi; Tateyama, Kojiro

    2015-01-01

    Inadequate information is available about the cerebral blood flow and surgical strategies of a direct aneurysmal carotid cavernous fistula (daCCF). We report a quantitative analysis of flow velocity and volume using preoperative time-resolved phase-contrast MRI (four-dimensional (4D) flow MRI) in a daCCF. This is the first report of 4D flow findings with a daCCF. A 55-year-old woman developed a sudden headache and bruit of the right orbit, and MRI suggested the presence of a daCCF. Quantitative analysis using preoperative 4D flow MRI revealed the flow volume of the right internal carotid artery. The daCCF was successfully treated by high-flow bypass using a radial artery graft and internal carotid artery trapping. Postoperative angiography showed a complete obliteration of the daCCF. Studies to collect data from additional cases are required so that 4D flow findings can be further used in the management of daCCFs. PMID:25612750

  20. Hemodynamics and right-ventricle functional characteristics of a swine carotid artery-jugular vein shunt model of pulmonary arterial hypertension: An 18-month experimental study

    PubMed Central

    Luo, Xiaoju; Huang, Yuanyuan; He, Yun; Li, Zhixian

    2015-01-01

    The continuous changes in pulmonary hemodynamic properties and right ventricular (RV) function in pulmonary arterial hypertension (PAH) have not been fully characterized in large animal model of PAH induced by a carotid artery–jugular vein shunt. A minipig model of PAH was induced by a surgical anastomosis between the left common carotid artery and the left jugular vein. The model was validated by catheter examination and pathologic analyses, and the hemodynamic features and right-ventricle functional characteristics of the model were continuously observed by Doppler echocardiography. Of the 45 minipigs who received the surgery, 27 survived and were validated as models of PAH, reflected by mean pulmonary artery pressure ≥25 mmHg, and typical pathologic changes of pulmonary arterial remodeling and RV fibrosis. Non-invasive indices of pulmonary hemodynamics (pulmonary artery accelerating time and its ratio to RV ventricular ejection time) were temporarily increased, then reduced later, similar to changes in tricuspid annular displacement. The Tei index of the RV was elevated, indicating a progressive impairment in RV function. Surgical anastomosis between carotid artery and jugular vein in a minipig is effective to establish PAH, and non-invasive hemodynamic and right-ventricle functional indices measured by Doppler echocardiography may be used as early indicators of PAH. PMID:25595189

  1. Extracranial-Intracranial Bypass Surgery for Stroke Prevention in Hemodynamic Cerebral Ischemia: The Carotid Occlusion Surgery Study: A Randomized Trial

    PubMed Central

    Powers, William J.; Clarke, William R.; Grubb, Robert L.; Videen, Tom O; Adams, Harold P.; Derdeyn, Colin P.

    2013-01-01

    Context Patients with symptomatic atherosclerotic internal carotid artery occlusion (AICAO) and hemodynamic cerebral ischemia are at high risk for subsequent stroke when treated medically. Objective Test the hypothesis that extracranial-intracranial (EC-IC) bypass surgery, added to best medical therapy, reduces subsequent ipsilateral ischemic stroke in patients with recently symptomatic AICAO and hemodynamic cerebral ischemia. Design Parallel group, randomized, open-label, blinded-adjudication clinical treatment trial conducted from 2002–2010. Setting 49 clinical centers and 18 positron emission tomography (PET) centers in the United States and Canada. The majority were academic medical centers. Participants Arteriographically-confirmed AICAO causing hemispheric symptoms within 120 days and hemodynamic cerebral ischemia identified by ipsilateral increased oxygen extraction fraction measured by PET. 195 were randomized: 97 to surgery and 98 to no surgery. Follow-up for the primary endpoint until occurrence, 2 years, or end of trial was 99% complete. No participant withdrew because of adverse events. Interventions Anastomosis of superficial temporal artery branch to a middle cerebral artery cortical branch for the surgical group. Anti-thrombotic therapy and risk factor intervention were recommended for all. Main Outcome Measure For all participants who were assigned to surgery and received surgery, the combination of (1) all stroke and death from surgery through 30 days post surgery and (2) ipsilateral ischemic stroke within 2 years of randomization. For the nonsurgical group and participants assigned to surgery who did not receive surgery was the combination of (1) all stroke and death from randomization to randomization plus 30 days and (2) ipsilateral ischemic stroke within two years of randomization. Results The trial was terminated early for futility. Two-year rates for the primary endpoint were 21.0% (95% CI, 12.8% to 29.2%; 20 events) for the surgical group

  2. Comparison of Endovascular Treatments of Ruptured Dissecting Aneurysms of the Intracranial Internal Carotid Artery and Vertebral Artery with a Review of the Literature

    PubMed Central

    Byoun, Hyoung Soo; Choi, Kyu Sun; Chun, Hyoung Joon; Ko, Yong; Bak, Koang Hum

    2016-01-01

    Objective Subarachnoid hemorrhage (SAH) caused by rupture of an internal carotid artery (ICA) or vertebral artery (VA) dissecting aneuryesm is rare. Various treatment strategies have been used for ruptured intracranial dissections. The purpose of this study is to compare the clinical and angiographic characteristics and outcomes of endovascular treatment for ruptured dissecting aneurysms of the intracranial ICA and VA. Methods The authors retrospectively reviewed a series of patients with SAH caused by ruptured intracranial ICA and VA dissecting aneurysms from March 2009 to April 2014. The relevant demographic and angiographic data were collected, categorized and analyzed with respect to the outcome. Results Fifteen patients were identified (6 ICAs and 9 VAs). The percentage of patients showing unfavorable initial clinical condition and a history of hypertension was higher in the VA group. The initial aneurysm detection rate and the percentage of fusiform aneurysms were higher in the VA group. In the ICA group, all patients were treated with double stent-assisted coiling, and showed favorable outcomes. In the VA group, 2 patients were treated with double stent-assisted coiling and 7 with endovascular trapping. Two patients died and 1 patient developed severe disability. Conclusion Clinically, grave initial clinical condition and hypertension were more frequent in the VA group. Angiographically, bleb-like aneurysms were more frequent in the ICA group and fusiform aneurysms were more frequent in the VA group. Endovascular treatment of these aneurysms is feasible and the result is acceptable in most instances. PMID:27651862

  3. The effect of hemodynamics on the failure of endovascular coiling in cerebral aneurysms

    NASA Astrophysics Data System (ADS)

    Cha, Kyung Se; Lieber, Baruch B.

    2005-11-01

    Today the treatment of intracranial aneurysms with endovascular coils is an established procedure which has several advantages compared to surgical clipping. However, coil compaction with recanalization remains a long term problem and is observed in approximately 50% of large and giant aneurysm cases over a 5-6 year follow-up period. Clinical data suggest that the coil packing density and the location and size of the aneurysm are important parameters in the long term outcome, suggesting that the repeated impulses exerted by the impingement of the pulsatile blood flow on the coil are mainly responsible for coil compaction. To test this hypothesis we will present: 1. patient specific simulations of two different clinical cases having high and low coil compaction risk respectively; 2. a systematic study on the effects of various geometrical parameters (bifurcation angle, ratio of aneurysm neck size to parent vessel diameter) on the magnitude of the total force on the coil, using idealized configurations. In all cases the three-dimensional laminar flow computations have been carried out using an unstructured, finite-element, Navier-Stokes solver. It will be shown that the ratio of aneurysm neck size to parent vessel diameter has the largest influence on the maximum force on the coil, which is less sensitive to the bifurcation angle.

  4. The Computational Fluid Dynamics Rupture Challenge 2013--Phase II: Variability of Hemodynamic Simulations in Two Intracranial Aneurysms.

    PubMed

    Berg, Philipp; Roloff, Christoph; Beuing, Oliver; Voss, Samuel; Sugiyama, Shin-Ichiro; Aristokleous, Nicolas; Anayiotos, Andreas S; Ashton, Neil; Revell, Alistair; Bressloff, Neil W; Brown, Alistair G; Chung, Bong Jae; Cebral, Juan R; Copelli, Gabriele; Fu, Wenyu; Qiao, Aike; Geers, Arjan J; Hodis, Simona; Dragomir-Daescu, Dan; Nordahl, Emily; Bora Suzen, Yildirim; Owais Khan, Muhammad; Valen-Sendstad, Kristian; Kono, Kenichi; Menon, Prahlad G; Albal, Priti G; Mierka, Otto; Münster, Raphael; Morales, Hernán G; Bonnefous, Odile; Osman, Jan; Goubergrits, Leonid; Pallares, Jordi; Cito, Salvatore; Passalacqua, Alberto; Piskin, Senol; Pekkan, Kerem; Ramalho, Susana; Marques, Nelson; Sanchi, Stéphane; Schumacher, Kristopher R; Sturgeon, Jess; Švihlová, Helena; Hron, Jaroslav; Usera, Gabriel; Mendina, Mariana; Xiang, Jianping; Meng, Hui; Steinman, David A; Janiga, Gábor

    2015-12-01

    With the increased availability of computational resources, the past decade has seen a rise in the use of computational fluid dynamics (CFD) for medical applications. There has been an increase in the application of CFD to attempt to predict the rupture of intracranial aneurysms, however, while many hemodynamic parameters can be obtained from these computations, to date, no consistent methodology for the prediction of the rupture has been identified. One particular challenge to CFD is that many factors contribute to its accuracy; the mesh resolution and spatial/temporal discretization can alone contribute to a variation in accuracy. This failure to identify the importance of these factors and identify a methodology for the prediction of ruptures has limited the acceptance of CFD among physicians for rupture prediction. The International CFD Rupture Challenge 2013 seeks to comment on the sensitivity of these various CFD assumptions to predict the rupture by undertaking a comparison of the rupture and blood-flow predictions from a wide range of independent participants utilizing a range of CFD approaches. Twenty-six groups from 15 countries took part in the challenge. Participants were provided with surface models of two intracranial aneurysms and asked to carry out the corresponding hemodynamics simulations, free to choose their own mesh, solver, and temporal discretization. They were requested to submit velocity and pressure predictions along the centerline and on specified planes. The first phase of the challenge, described in a separate paper, was aimed at predicting which of the two aneurysms had previously ruptured and where the rupture site was located. The second phase, described in this paper, aims to assess the variability of the solutions and the sensitivity to the modeling assumptions. Participants were free to choose boundary conditions in the first phase, whereas they were prescribed in the second phase but all other CFD modeling parameters were not

  5. Hemodynamics in the Circle of Willis with Internal Carotid Artery Stenosis under Cervical Rotatory Manipulation: A Finite Element Analysis

    PubMed Central

    Lin, Weishen; Ma, Xiaokang; Deng, Datai; Li, Yikai

    2015-01-01

    Background The circle of Willis (CoW) plays an important role in cerebral collateral circulation. The hemodynamics changes in the CoW have usually been associated with the internal carotid artery (ICA) stenosis, but whether rotatory manipulation will affect it remains unknown. Material/Methods In this study we attempted to analyze the influence of rotatory manipulation on the hemodynamics in the CoW in models with or without ICA stenosis by means of finite element analysis. For this purpose, the CoW was reasonably simplified and a fluid-solid coupling 3D finite element model was created by using MIMICS10.0 and ANSYS14.5. The healthy (without stenosis) and the diseased (ratios of stenosis include 15%, 30%, 45%, 60%, 70%, 80%, and 90%) situations were simulated. A remote displacement of 60° was applied at a distal ICA (the right ICA was chosen here) to imitate the rotatory manipulation. Blood flow was then monitored at the anterior communicating artery (ACoA) and posterior communicating arteries (PCoA). Results Before the conduction of rotatory manipulation, blood flow changed significantly only when the stenosis ratio was increased to more than 70%, and the situation did not have significant difference after the application of remote displacement except the model with stenosis ration of 90%. Conclusions The result suggests that the rotatory manipulation does not have an obvious influence on the blood flow in the CoW when the stenosis of ICA is less than 90%, and this kind of manipulation is suggested to be a safe technique in most of the clinical applications. PMID:26103051

  6. Hemodynamic role of ophthalmic artery collateral in internal carotid artery occlusion.

    PubMed

    Tatemichi, T K; Chamorro, A; Petty, G W; Khandji, A; Oropeza, L A; Duterte, D I; Mohr, J P

    1990-03-01

    We performed duplex and transcranial Doppler studies in 36 patients with angiographically documented internal carotid artery occlusion (ICAO) to determine the effect of ophthalmic artery collateral (OAC) on measures of vascular resistivity both proximal and distal to the occlusion. Resistance in the common carotid artery, measured by the resistivity index, was significantly lower in the group with OAC than in those without OAC, indicating a shunt to the low resistance intracranial circuit. The pulsatility index (PI) of the Doppler signal in the ipsilateral middle cerebral artery, a measure of both inflow pressure and distal vascular resistance, did not differ between those with and without OAC. However, the presence of circle of Willis collateral pathways (anterior communicating and/or posterior communicating artery) did appear to have a significant effect on pulsatility. When both were present angiographically, PI was higher than in the group with only 1 Willisian collateral. These findings suggest that OAC has a marginal effect on vascular resistance in arterial bed distal to an ICAO, while Willisian collaterals appear to have a more important role in cerebral perfusion, as measured indirectly by Doppler methods.

  7. Hemodynamics

    PubMed Central

    Secomb, Timothy W.

    2016-01-01

    A review is presented of the physical principles governing the distribution of blood flow and blood pressure in the vascular system. The main factors involved are the pulsatile driving pressure generated by the heart, the flow characteristics of blood, and the geometric structure and mechanical properties of the vessels. The relationship between driving pressure and flow in a given vessel can be understood by considering the viscous and inertial forces acting on the blood. Depending on the vessel diameter and other physical parameters, a wide variety of flow phenomena can occur. In large arteries, the propagation of the pressure pulse depends on the elastic properties of the artery walls. In the microcirculation, the fact that blood is a suspension of cells strongly influences its flow properties and leads to a non-uniform distribution of hematocrit among microvessels. The forces acting on vessel walls include shear stress resulting from blood flow and circumferential stress resulting from blood pressure. Biological responses to these forces are important in the control of blood flow and the structural remodeling of vessels, and also play a role in major disease processes including hypertension and atherosclerosis. Consideration of hemodynamics is essential for a comprehensive understanding of the functioning of the circulatory system. PMID:27065172

  8. Cerebrospinal Fluid Enhancement on Fluid Attenuated Inversion Recovery Images After Carotid Artery Stenting with Neuroprotective Balloon Occlusions: Hemodynamic Instability and Blood-Brain Barrier Disruption

    SciTech Connect

    Ogami, Ryo Nakahara, Toshinori; Hamasaki, Osamu; Araki, Hayato; Kurisu, Kaoru

    2011-10-15

    Purpose: A rare complication of carotid artery stenting (CAS), prolonged reversible neurological symptoms with delayed cerebrospinal fluid (CSF) space enhancement on fluid attenuated inversion recovery (FLAIR) images, is associated with blood-brain barrier (BBB) disruption. We prospectively identified patients who showed CSF space enhancement on FLAIR images. Methods: Nineteen patients-5 acute-phase and 14 scheduled-underwent 21 CAS procedures. Balloon catheters were navigated across stenoses, angioplasty was performed using a neuroprotective balloon, and stents were placed with after dilation under distal balloon protection. CSF space hyperintensity or obscuration on FLAIR after versus before CAS indicated CSF space enhancement. Correlations with clinical factors were examined. Results: CSF space was enhanced on FLAIR in 12 (57.1%) cases. Postprocedural CSF space enhancement was significantly related to age, stenosis rate, acute-stage procedure, and total occlusion time. All acute-stage CAS patients showed delayed enhancement. Only age was associated with delayed CSF space enhancement in scheduled CAS patients. Conclusions: Ischemic intolerance for severe carotid artery stenosis and temporary neuroprotective balloon occlusion, causing reperfusion injury, seem to be the main factors that underlie BBB disruption with delayed CSF space enhancement shortly after CAS, rather than sudden poststenting hemodynamic change. Our results suggest that factors related to hemodynamic instability or ischemic intolerance seem to be associated with post-CAS BBB vulnerability. Patients at risk for hemodynamic instability or with ischemic intolerance, which decrease BBB integrity, require careful management to prevent intracranial hemorrhagic and other post-CAS complications.

  9. Aneurysm

    MedlinePlus

    ... Arterial aneurysms. In: Cronenwett JL, Johnston KW, eds. Rutherford's Vascular Surgery . 8th ed. Philadelphia, PA: Elsevier Saunders; ... general considerations. In: Cronenwett JL, Johnston KW, eds. Rutherford's Vascular Surgery . 8th ed. Philadelphia, PA: Elsevier Saunders; ...

  10. 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

  11. Obliteration of a giant fusiform carotid terminus-M1 aneurysm after distal clip application and extracranial-intracranial bypass. Case report.

    PubMed

    Ferroli, P; Ciceri, E; Parati, E; Minati, L; Broggi, G

    2007-06-01

    Giant intracranial aneurysms may not be amenable to direct surgical clipping or endovascular coiling because of three critical factors: 1) lack of clear aneurysmal neck; 2) giant size; 3) involvement with critical perforating or branch vessels. Techniques of flow redirection, however, may offer an alternative treatment strategy for these difficult lesions. In this paper, we report on the use of this alternative strategy in the successful treatment of a left giant fusiform carotid terminus-M1 aneurysm in a 16 year-old boy suffering from Ehler-Danlos disease. This patient was admitted to our Institution because his aneurysm was continuing to be increasing in size, despite a previous ligation of his left cervical ICA which was performed at another institution 2 years earlier after the patient had experienced a hemorrhagic stroke. Upon admission, a neurological examination revealed a slight motor aphasia with mild right hemiparesis, remnant of the ancient stroke. Because of its size and the involvement with M1 perforating arteries, a direct aneurysm attack was deemed inadvisable. After an initial ECA-ICA high flow bypass which spontaneously thrombosed, we performed a repeated high flow bypass with the application of a single clip on M1, right distal to the fusiform dilatation. After an uneventful postoperative course, we were unable to observe any new neurological deficits after surgery. A CT scan on postoperative day 1 revealed that the aneurysm had undergone a spontaneous thrombosis which was completely obliterated at the time of a 6-month follow-up angiogram. At that time, the ECA-ICA bypass was found to be patent. In conclusion the alternative of flow alteration strategies can be successfully used in the treatment of aneurysms that cannot be safely trapped or occluded by traditional neurosurgical methods.

  12. Aortic coarctation and carotid artery aneurysm in a patient with Hardikar syndrome: Cardiovascular implications for affected individuals.

    PubMed

    Ryan, Kaitlin M; Ellis, Alexander R; Raafat, Reem; Bhoj, Elizabeth J; Hakonarson, Hakon; Li, Dong; Schrier Vergano, Samantha

    2016-02-01

    Hardikar syndrome is a multiple congenital anomaly syndrome first characterized in 1992 by Hardikar et al. to describe two individuals with cholestasis, cleft lip/palate, retinal pigmentation, intestinal abnormalities, and genitourinary anomalies. Between 1992 and 2002, four individuals with Hardikar syndrome were reported in the literature. The fourth individual [Maluf et al. (2002), Transplantation 74:1058-1061; Poley and Proud (2008) Am J Med Genet Part A 146A:2473-2479], who had progressive cholestatic liver disease ultimately requiring liver transplantation, has continued to be followed at our institution. Recently, at the age of 14 years, during an evaluation for refractory hypertension, she was found to have developed coarctation of the aorta that was treated with aortic angioplasty and stenting, dramatically improving her hypertension. Further vascular investigation also revealed a small aneurysm of her carotid artery requiring neurosurgical evaluation and anticoagulant therapy. To our knowledge, these vascular anomalies have not been reported in Hardikar syndrome and the high association of congenital heart disease in the individuals with Hardikar syndrome has not been further addressed. Herein, we discuss this additional clinical information, speculate briefly on possible molecular etiologies, and discuss potential cardiac surveillance recommendations. We hope that broadening the known phenotype of this very rare disorder will further aid clinicians in their management and surveillance for these individuals.

  13. Hemodynamic study of internal carotid artery stenosis and occlusion: value of combined isotopic measurements of regional cerebral blood flow and blood volume

    SciTech Connect

    Derlon, J.M.; Bouvard, G.; Lechevalier, B.; Dupuy, B.; Maiza, D.; Hubert, P.; Courtheoux, P.; Peres, J.C.; Houtteville, J.P.

    1986-05-01

    The assessment of the intracranial hemodynamic consequences of obstructive lesions of the carotid artery by measuring resting rCBF is inadequate because cerebral blood flow may remain constant in spite of significant drops in the intraluminal pressure due to autoregulation. Moreover, flow may be permanently decreased following cerebral infarction, even if the arterial anatomical conditions have resumed their normal state because of the decreased metabolic demand of an infarcted area. Measurement of the regional cerebral blood volume (rCBV) helps with the hemodynamic assessment of these conditions, since there is a linear and inverse relationship between intraarterial pressure and intracranial blood volume. In 24 patients exhibiting various carotid and ischemic brain lesions we studied both rCBF and rCBV. The latter is a comparative measure between hemispheres obtained by single photon emission tomography after autotransfusion of 99mTechnetium labeled erythrocytes. There was no correlation between rCBF and clinical status, CT scan or arterial lesions. There was no correlation between rCBV and clinical status or CT scan. There was, however, an interesting correlation between rCBV and the severity of the arterial lesion. The rCBV was symmetrical in all patients with normal or moderately stenotic carotid arteries before and after operation. In some patients with severe unilateral stenosis or occlusion, there was a significant relative increase of rCBV in the hemisphere downstream from the lesion, which disappeared after surgery (endarterectomy or extra-intracranial bypass). In some patients with severe and bilateral carotid lesions, we noted an asymmetry in rCBV that disappeared after a unilateral operation. Other patients with similar lesions develop asymmetry only after an operation that resulted in a relative increase in rCBV in the hemisphere supplied by the non-operated artery.

  14. Direct suction decompression and fenestrated clip reconstruction of complex paraclinoid carotid artery aneurysm: operative video and nuances of skull base technique.

    PubMed

    Liu, James K

    2015-07-01

    Direct microsurgical clipping of complex paraclinoid carotid artery aneuryms remains a formidable technical challenge due to the auneurysm's deep location at the skull base, with adjacent bony anatomy, large size, wide neck, and complex neuroanatomical relationships. In this operative video atlas manuscript, the author demonstrates a step-by-step technique for microsurgical clip reconstruction of a large complex ventral paraclinoid carotid artery aneurysm, using a trapping and direct suction decompression strategy followed by multiple fenestrated clip reconstruction of the internal carotid artery (ICA) via a modified orbitozygomatic approach. The nuances of skull base techniques are illustrated including extradural optic nerve decompression, extradural anterior clinoidectomy, incision of the falciform ligament to untether the optic nerve, and release of the distal durai ring to obtain proximal control. Reconstruction of the ICA and preservation of the anterior choroidal artery were achieved with multiple fenestrated clips. Aneurysm obliteration and patency of flow through the ICA was confirmed on video indocyanine green and catheter angiography. Although novel endovascular strategies continue to evolve, these microsurgical skull base techniques should remain in the surgical armamentarium for treating these complex cranial base vascular lesions. The video can be found here: http://youtu.be/IPS6lslk1ds.

  15. Retrograde suction decompression of a large internal carotid aneurysm using a balloon guide catheter combined with a blood-returning circuit and STA-MCA bypass: a technical note.

    PubMed

    Matano, Fumihiro; Mizunari, Takayuki; Kominami, Shushi; Suzuki, Masanori; Fujiki, Yu; Kubota, Asami; Kobayashi, Shiro; Murai, Yasuo; Morita, Akio

    2017-04-01

    It is difficult to treat large internal carotid aneurysms with simple surgical clipping. Here, we present a retrograde suction decompression (RSD) procedure for large internal carotid aneurysms using a balloon guide catheter combined with a blood-returning circuit and a superficial temporal artery to middle cerebral artery (STA-MCA) bypass.All patients underwent an STA-MCA bypass before the temporary occlusion of the internal carotid artery (ICA). A 6-French sheath was inserted into the common carotid artery (CCA), and a 6-French Patrive balloon catheter was placed into the ICA 5 cm past the bifurcation. Aneurysm exposure was obtained; temporary clips were placed on the proximal M1, A1, and posterior communicating (Pcom) segments; and an extension tube was then connected to the balloon catheter. A three-way stopcock was placed, and aspiration was performed through the device to collapse the aneurysm. The aspirated blood was returned to a venous line with an added heparin to prevent anemia after aspiration. During the decompression, the blood flow to the cortical area was supplied through the STA-MCA bypass. After the aneurysm collapse, the surgeon carefully dissected the perforating artery from the aneurysm dome or neck, and permanent clips were then placed on the aneurysm neck. Our procedure has several advantages, such as STA-MCA bypass without external carotid artery occlusion for preventing ischemic complications of the cortical area, anemia may be avoided because of the return of the aspirated blood, and a hybrid operation room is not required to perform this method.

  16. Aneurysms

    MedlinePlus

    ... Adults Making Your Wishes Known Home & Community Home › Aging & Health A to Z › Aneurysms Font size A A A Print Share Glossary Basic Facts & Information Causes & Symptoms Diagnosis & Tests Care & Treatment Lifestyle & Management Other Resources Caregiving How ...

  17. Endovascular parent-artery occlusion of large or giant unruptured internal carotid artery aneurysms. A long-term single-center experience.

    PubMed

    Shimizu, Kampei; Imamura, Hirotoshi; Mineharu, Yohei; Adachi, Hidemitsu; Sakai, Chiaki; Tani, Shoichi; Arimura, Koichi; Beppu, Mikiya; Sakai, Nobuyuki

    2017-03-01

    The development of stent-like devices has increased treatment options for complex internal carotid artery (ICA) aneurysms, but the optimal treatment remains unclear. The purpose of this study was to evaluate the safety and efficacy of endovascular parent-artery occlusion (PAO) for ICA aneurysms. We retrospectively reviewed 28 patients with unruptured ICA aneurysms ⩾10mm treated with PAO between April 2002 and March 2015 at our institution. Patients who developed neurologic symptoms or with venous-phase delay >2s during balloon test occlusion were not treated by PAO. Patients with venous-phase delays of 1-2s underwent superficial temporal artery to middle cerebral artery (STA-MCA) bypass prior to PAO. The median patient age was 65 (range, 26-84)years. Nineteen aneurysms (68%) were located in the cavernous segment. The median aneurysm size was 25 (range 11-40)mm. Venous-phase delay of 1-2s was observed in five patients. Perioperative ischemic complications (N=9, 32%), which occurred within 30days after treatment, were significantly associated with venous-phase delays of 1-2s (p<0.01) and history of hypertension (p<0.01). Six-month morbidity was observed in one (3.6%) patient. Complete occlusion at final follow-up and delayed (i.e. ⩾31days after treatment) ischemic events were observed in 100% and 0% of patients, respectively, over a median period of 63 (range, 6-147) months. Despite the high frequency of perioperative ischemic episodes, endovascular PAO with selective use of STA-MCA bypass showed excellent long-term outcomes in patients with unruptured ICA aneurysms ⩾10mm.

  18. The effects of stroma-free and dextran-conjugated hemoglobin on hemodynamics and carotid blood flow in hemorrhaged guinea pigs.

    PubMed

    Caron, A; Menu, P; Faivre-Fiorina, B; Labrude, P; Vigneron, C

    1999-01-01

    Hemoglobin solutions are potential resuscitative fluids with volume expanding and oxygen delivery abilities developed to reduce the use of blood transfusion. Most hemoglobin solutions in clinical trials increase transiently arterial pressure by inhibiting nitric oxide-dependent vasodilation. Our objective was to compare the effects on central hemodynamics and carotid blood flow of two hemoglobin solutions after resuscitation from hemorrhage in anesthetized guinea pigs. After anesthesia and instrumentation, severe hemorrhage was induced by withdrawing 50% of the blood volume. Resuscitation was performed after 15 min of hypovolemia with 5% albumin, stroma-free hemoglobin, or hemoglobin conjugated to dextran-benzenetetracarboxylate (Dex-BTC-Hb). The mean arterial pressure (MAP), carotid blood flow (CBF), vascular resistance index and heart rate (HR) were monitored for 3 hours after resuscitation. After hemorrhage, MAP and CBF dropped to 57.6 +/- 4.4% and 58.9 +/- 3.7% of control values respectively. Albumin failed to maintain hemodynamics in the decompensatory phase of shock. Both hemoglobin solutions gave rise to a transient increase in MAP (35%); stroma-free hemoglobin increased the CBF (150%) and resistance index (24%) whereas Dex-BTC-Hb had no effect on CBF and vascular resistances. None of the solutions affected the HR. Modified hemoglobin has attenuated effects on CBF and resistance index compared to stroma-free hemoglobin. This may be due to a balance between the stimulation of nitric oxide synthesis by shear-stress and the inhibition of vasodilation by nitric oxide trapping.

  19. New Bone Formation after Ligation of the External Carotid Artery and Resection of a Large Aneurysmal Bone Cyst of the Mandible with Reconstruction: A Case Report

    PubMed Central

    Perumal, Colin; Mohamed, Ashraf; Singh, Avin

    2011-01-01

    The aneurysmal bone cyst (ABC) is a benign cystic and expanding osteolytic lesion consisting of bone-filled spaces of variable size, separated by connective tissue containing trabeculae of bone or osteoid tissue and osteoclast giant cells. Radiographic findings may vary from unicystic or moth-eaten radiolucencies to extensive multilocular lesions with bilateral expansion and destruction of mandibular cortices. Treatment modalities include curettage (with reported recurrences) and resection with immediate reconstruction. The main arterial and feeder vessels may be embolized to prevent profuse intraoperative blood loss and achieve a bloodless surgical field. Failed embolization may necessitate ligation of the external carotid artery of the affected side. PMID:23450035

  20. Monitoring of hemodynamic change in patients with carotid artery stenosis during the tilt test using wearable near-infrared spectroscopy.

    PubMed

    Igarashi, Takahiro; Sakatani, Kaoru; Fujiwara, Norio; Murata, Yoshihiro; Suma, Takeshi; Shibuya, Tadashi; Hirayama, Teruyasu; Katayama, Yoichi

    2013-01-01

    Transient ischemic attack (TIA) is a major complication in patients with carotid artery stenosis. Patients with severe stenosis sometimes complain of orthostatic dizziness, such as syncope. The purpose of this study was to examine the usefulness of near-infrared spectroscopy (NIRS) for evaluating cerebral circulation in patients with carotid artery stenosis during head-up tilt test (HUTT). Fourteen patients with carotid artery stenosis and nine normal control subjects participated. In addition to blood pressure monitoring, hemoglobin (Hb) values (oxy-Hb, deoxy-Hb, and total Hb) were recorded by a wearable NIRS instrument with a high time resolution during HUTT. Oxy-Hb, which decreased initially when the test table was elevated, subsequently increased in normal volunteers and patients with carotid artery stenosis and did not differ significantly between the two groups. However, the oxy-Hb reduction in the carotid artery stenosis group (-0.02 ± 0.03 a.u.) at 30 s after elevation of the table was significantly larger than in the normal group (0.02 ± 0.02 a.u., P < 0.01). Our results indicate that oxy-Hb reduction in patients with carotid artery stenosis may be related to orthostatic dizziness. We concluded that NIRS monitoring is useful for evaluating cerebral autoregulation in patients with severe carotid artery stenosis.

  1. Urgent treatment of severe symptomatic direct carotid cavernous fistula caused by ruptured cavernous internal carotid artery aneurysm using high-flow bypass, proximal ligation, and direct distal clipping: Technical case report

    PubMed Central

    Hasegawa, Hirotaka; Inoue, Tomohiro; Tamura, Akira; Saito, Isamu

    2014-01-01

    Background: Direct carotid cavernous fistula (CCF) secondary to ruptured carotid cavernous aneurysms (CCAs) is rare, but patients with this condition who develop acutely worsening and severe neuro-ophthalmic symptoms require urgent treatment. Endovascular methods are the first-line option, but this modality may not be available on an urgent basis. Case Description: In this article, we report a 45-year-old female with severe direct CCF due to rupture of the CCA. She presented with intractable headache and acute worsening of double vision and visual acuity. Emergent radiographic study revealed high-flow fistula tracked from the CCA toward the contralateral cavernous sinus and drained into the engorged left superior orbital vein. To prevent permanent devastating neuro-ophthalmic damages, urgent high-flow bypass with placement of a radial artery graft was performed followed by right cervical internal carotid artery (ICA) ligation and the clipping of the ICA at the C3 portion, proximal to the ophthalmic artery. In the immediate postoperative period, her symptoms resolved and angiography confirmed patency of the high-flow bypass and complete occlusion of the CCF. Conclusion: With due consideration of strategy and techniques to secure safety, open surgical intervention with trapping and bypass is a good treatment option for direct severe CCF when the endovascular method is not available, not possible, or is unsuccessful. PMID:24818056

  2. Surgical flow modification of the anterior cerebral artery-anterior communicating artery complex in the management of giant aneurysms of internal carotid artery bifurcation: An alternative for a difficult clip reconstruction

    PubMed Central

    Pahl, Felix Hendrik; de Oliveira, Matheus Fernandes; Beer-Furlan, André Luiz; Rotta, José Marcus

    2016-01-01

    Background: Internal carotid artery bifurcation (ICAb) aneurysms account for about 2–15% of all intracranial aneurysms. In giant and complex cases, treatment may be difficult and dangerous, once some aneurysms have wide neck and anterior cerebral artery (ACA) and middle cerebral artery (MCA) may arise from the aneurysm itself. Clip reconstruction may be difficult in such cases. Whenever possible, the occlusion of ACA transform the bifurcation in a single artery reconstruction (ICA to MCA), much easier than a bifurcation reconstruction. Methods: In patients with giant and complex ICAb aneurysms, we propose routine preoperative angiography with anatomical evaluation of anterior communicating artery (ACoA) patency during cervical common carotid compression with concomitant contralateral carotid artery injection. This allowed visualization of the expected reversal of flow in the A1 segment–ACoA complex. When test is positive, we can perform ipsilateral ACA (A1 segment) clip occlusion and flow modification of the ACA-ACoA complex transforming a three vessel (ICA, ACA, and MCA) reconstruction into a two vessel (ICA and MCA) reconstruction. Results: Two patients were treated, with 100% of occlusion and good outcome. Conclusions: Surgical treatment of giant and complex ICAb may be achieved with acceptable morbidity. PMID:27313968

  3. Xenon/CT CBF measurements as valuable diagnostic tool in a case of bilateral occlusive cerebrovascular disease associated with intracranial aneurysm.

    PubMed

    Shumann, M U; Mirzai, S; Samii, M; Vorkapic, P

    1996-01-01

    A patient with the coincidental occurrence of a right internal carotid artery (ICA) stenosis and asymptomatic ipsilateral infraclinoidal ICA aneurysm is presented. CBF measurements including testing of the cerebrovascular reserve capacity (CRC) demonstrated a compromise of cerebral blood flow (CBF) within the anterior circulation of the affected side. We treated the patient in one operation by aneurysm clipping and subsequent carotid endarterectomy (CEA). 10 months later she presented with an occlusion of the contralateral ICA. CBF measurements showed sufficient resting flow and CRC on both sides. One year later repeat measurements disclosed a lowered resting CBF and diminished CRC on the affected side. Extracranial/Intracranial (EC/IC) artery bypass improved both symptoms and CBF/CRC values. The authors propose to treat symptomatic ICA stenosis and concurrent silent ipsilateral intracranial aneurysms at once if the patient is eligible for aneurysm surgery. CBF measurements should be performed before surgery. In a medically compromised patient carotid endarterectomy alone appears to be justifiable. In cases of symptomatic aneurysm and concurrent ICA stenosis a CEA can be added to aneurysm clipping to improve the hemodynamic situation for a better postoperative management. Xenon/CT investigations are suitable to provide important cerebral blood flow information. Together with angiography and clinical judgment it allows to identify patients with hemodynamic insufficiency. These are suitable candidates for an operative procedure to augment cerebral blood flow and to improve symptoms.

  4. Effects of Intraluminal Thrombus on Patient-Specific Abdominal Aortic Aneurysm Hemodynamics via Stereoscopic Particle Image Velocity and Computational Fluid Dynamics Modeling

    PubMed Central

    Chen, Chia-Yuan; Antón, Raúl; Hung, Ming-yang; Menon, Prahlad; Finol, Ender A.; Pekkan, Kerem

    2014-01-01

    The pathology of the human abdominal aortic aneurysm (AAA) and its relationship to the later complication of intraluminal thrombus (ILT) formation remains unclear. The hemodynamics in the diseased abdominal aorta are hypothesized to be a key contributor to the formation and growth of ILT. The objective of this investigation is to establish a reliable 3D flow visualization method with corresponding validation tests with high confidence in order to provide insight into the basic hemodynamic features for a better understanding of hemodynamics in AAA pathology and seek potential treatment for AAA diseases. A stereoscopic particle image velocity (PIV) experiment was conducted using transparent patient-specific experimental AAA models (with and without ILT) at three axial planes. Results show that before ILT formation, a 3D vortex was generated in the AAA phantom. This geometry-related vortex was not observed after the formation of ILT, indicating its possible role in the subsequent appearance of ILT in this patient. It may indicate that a longer residence time of recirculated blood flow in the aortic lumen due to this vortex caused sufficient shear-induced platelet activation to develop ILT and maintain uniform flow conditions. Additionally, two computational fluid dynamics (CFD) modeling codes (Fluent and an in-house cardiovascular CFD code) were compared with the two-dimensional, three-component velocity stereoscopic PIV data. Results showed that correlation coefficients of the out-of-plane velocity data between PIV and both CFD methods are greater than 0.85, demonstrating good quantitative agreement. The stereoscopic PIV study can be utilized as test case templates for ongoing efforts in cardiovascular CFD solver development. Likewise, it is envisaged that the patient-specific data may provide a benchmark for further studying hemodynamics of actual AAA, ILT, and their convolution effects under physiological conditions for clinical applications. PMID:24316984

  5. The Interference Phenomenon of Microcatheters in the Jailing Treatment for Internal Carotid Artery Side Wall Aneurysms with an Open Cell Stent System

    PubMed Central

    Yoo, Minwook; Kim, Seung-Hwan; Choi, Byeong-Sam; Kim, Hae Yu; Lee, SungJun; Kim, Sung Tae; Jeong, Hae Woong

    2016-01-01

    Objective Excelsior XT-27 (Stryker Neurovascular, Fremont, CA, USA) or Rebar 27 (eV3 Covidien, Irvine, CA, USA) microcatheters have recently been used to overcome the limitations of the Renegade Hi-Flo microcatheter such as interference between two microcatheters (one for stent delivery and the other for cerebral aneurysm coiling) during the jailing technique. We evaluated differences and influential factors related to the interference phenomenon according to these two microcatheters group. Materials and Methods Between June 2011 and September 2013, the jailing technique was applied to 94 internal cerebral artery (ICA) aneurysms. The jailing technique with the Neuroform EZ stent system was performed using Renegade (n = 22), Rebar (n = 35), and XT-27 microcatheters (n = 37). In the Renegade Hi-Flo microcatheter group, the jailing technique was successful in 19/22 patients (86.4%) and interference between the two microcatheters occurred in 6/21 patients (28.6%). In the Rebar and XT-27 microcatheter group, the jailing technique was successful in 71/72 patients (98.6%) and interference between the two microcatheters occurred in 1/72 patients (1.4%). Results There was a significant difference in the interference between the two delivered microcatheters group (p-value < 0.000) and the carotid siphon angle (p-value: 0.004) in the univariate analysis. In the multiple logistic regression analysis, the Rebar and XT-27 microcatheter group (odds ratio [OD] [95% confidence interval (CI)]; 31.277 [3.138-311.729], p-value: 0.003) and the carotid siphon angle (OD [95%CI]; 0.959 [0.922-0.997], p-value: 0.035) were found to be influential factors in the interference phenomenon. Conclusion The Rebar 27 and XT-27 microcatheters were more successful and exhibited less interference between the two microcatheters than the Renegade Hi-Flo microcatheter. PMID:28184346

  6. Oculomotor Paralysis, Postorbital Pain, and Hypopituitarism as First Presentations of Metastatic Gastric Cancer in the Pituitary Flourished by Internal Carotid Aneurysm

    PubMed Central

    Yang, Chuanwei; Zhang, Hongqiang; Zhang, Shiqiang; Liu, Ling; Ma, Binbin; Lou, Jiacheng; Sun, Xiaorui; Zhang, Bo

    2015-01-01

    Abstract Metastatic gastric cancer in the pituitary (MGCP) is rare. Few are known on the clinical and radiological characteristics of MGCP. To date, the coexistence of metastatic pituitary tumors and intracranial aneurysms has not been reported in literatures. We present a case of MGCP with internal carotid aneurysm in a 57-year-old woman, who presented with oculomotor paralysis, postorbital pain, and hypopituitarism as onset symptoms. The patient had a history of the surgical removal of gastric cancer. Magnetic resonance imaging and single-photon emission computed tomography revealed a recurrent sellar mass with intracranial and multiple bone metastases. The patient underwent subtotal removal of the tumor, followed by conformal radiotherapy and chemotherapy. Ten months after surgery, the patient died due to deterioration of her overall condition. We also reviewed and analyzed the clinical data, imaging features, and treatment methods of additional 4 cases with MGCP, which were reported in literatures. This study provides important clinical information for the diagnosis and treatment of MGCP. PMID:26683972

  7. Carotid hemodynamics is associated with monocyte count determined by serum homocysteine level in patients with essential hypertension.

    PubMed

    Jotoku, Masanori; Okura, Takafumi; Miyoshi, Ken-Ichi; Irita, Jun; Nagao, Tomoaki; Kukida, Masayoshi; Tanino, Akiko; Kudo, Kayo; Enomoto, Daijiro; Pei, Zouwei; Higaki, Jitsuo

    2015-01-01

    To examine the association between pulsatility index (PI) in the common carotid artery (CCA) as a marker of vascular resistance and cardiovascular risk factors, including serum homocysteine and inflammation, 67 hypertensive patients were enrolled. PI correlated with homocysteine and interleukin-6, monocyte count, gender, age and BMI, with monocyte count and age being independent determinants for PI. In turn, monocyte count correlated with homocysteine, tumor necrosis factor-alpha, and HDL-cholesterol, BMI, and gender, with HDL-cholesterol and homocysteine being independent determinants for monocyte count. These results indicated monocyte count determined by homocysteine is associated with arterial stiffness in hypertensive patients.

  8. Solitaire AB stent-assisted coiling embolization for the treatment of ruptured very small intracranial aneurysms.

    PubMed

    Zhang, Jifang; Wang, Donghai; Li, Xingang

    2015-12-01

    Recent advances in neuroradiological techniques have increasingly improved the diagnosis rate for very small aneurysms, particularly with the widespread use of three-dimensional cerebral angiography. However, the treatment of very small aneurysms remains a considerable challenge for neurosurgeons. Endovascular coiling has emerged as a potential treatment option for intracranial aneurysms. The aim of the present study was to evaluate the safety and efficacy of Solitaire AB stent-assisted coiling embolization for the treatment of ruptured very small intracranial aneurysms. This retrospective study included nine consecutive patients with ruptured very small intracranial aneurysms (≤3 mm) that underwent Solitaire AB stent-assisted coiling embolization. The aneurysms were located in the ophthalmic branch of the internal carotid artery (n=2), the posterior communicating branch of the internal carotid artery (n=4), the top of the basilar artery (n=1) and the middle cerebral artery (n=2). Solitaire AB stents were successfully implanted in all nine patients. Of the nice individuals, six patients exhibited complete occlusion at Raymond grade I and three patients exhibited occlusion at Raymond grade II. No aneurysm rupture was observed during the surgery. During the follow-up period of 8-13 months, no intracranial hemorrhage occurred. A total of seven patients underwent follow-up digital subtraction angiography at 5-10 months post-intervention. No recurrence of the aneurysms and no stenosis or occlusion of the parent arteries was observed. Therefore, Solitaire AB stent-assisted coil embolization was demonstrated to be a safe and effective treatment for ruptured very small intracranial aneurysms. The long-term efficacy of this technique may be improved by increasing the packing density around the aneurysmal neck and improving the hemodynamics.

  9. Carotid bypass for carotid occlusion.

    PubMed

    Hage, Ziad A; Behbahani, Mandana; Amin-Hanjani, Sepideh; Charbel, Fady T

    2015-07-01

    The 2-year risk of ipsilateral ischemic stroke following internal carotid artery occlusion (ICAO) in a patient undergoing maximal medical therapy is 5-8% per year. While medical therapy may reduce the risk of stroke, it does not completely eliminate it. Since the 1985 extracranial-intracranial (EC-IC) bypass study, additional trials have been conducted to further investigate the usefulness of EC-IC bypass surgery in more selected patients with cerebral ischemia and impaired hemodynamic reserve. These important studies will be briefly reviewed in this article, as well as a discussion regarding the utility of bypass surgery for ICAO in current clinical practice. In addition, a short discussion regarding the pathophysiology of carotid occlusion will be presented. We will also highlight our own institutional patient selection criteria based on the latest methods for hemodynamic assessment, as well as our intraoperative flow assisted surgical techniques (FAST), and post-operative patient follow-up.

  10. Simultaneous Endovascular Treatment of Tandem Internal Carotid Lesions: Case Report and Review of Literature.

    PubMed

    Cvetic, Vladimir; Dragas, Marko; Colic, Momcilo; Vukasinovic, Ivan; Radmili, Oliver; Ilic, Nikola; Koncar, Igor; Bascarevic, Vladimir; Ristanovic, Natasa; Davidovic, Lazar

    2016-07-01

    The incidence of concomitant extracranial carotid artery stenosis and ipsilateral intracranial carotid aneurysm has been reported to vary between 2.8% and 5%. These complex lesions may present a challenge for treatment decision-making. This case report describes an asymptomatic male patient with severe carotid bifurcation stenosis, coupled with an unruptured supraclinoid internal carotid aneurysm. Both lesions were treated simultaneously. Patient underwent carotid stenting followed by aneurysm coiling in the same setting without any complication.

  11. Giant thrombosed intracavernous carotid artery aneurysm presenting as Tolosa–Hunt syndrome in a patient harboring a new pathogenic neurofibromatosis type 1 mutation: a case report and review of the literature

    PubMed Central

    Conforti, Renata; Cirillo, Mario; Marrone, Valeria; Galasso, Rosario; Capaldo, Guglielmo; Giugliano, Teresa; Scuotto, Assunta; Piluso, Giulio; Melone, Mariarosa AB

    2014-01-01

    Neurofibromatosis type 1 (NF1) is a relatively common single-gene disorder, and is caused by heterozygous mutations in the NF1 gene that result in a loss of activity or in a nonfunctional neurofibromin protein. Despite the common association of NF1 with neurocutaneous features, its pathology can extend to numerous tissues not derived from the neural crest. Among the rare cerebrovascular abnormalities in NF1, more than 85% of cases are of purely occlusive or stenotic nature, with intracranial aneurysm being uncommon. Predominantly, the aneurysms are located in the internal carotid arteries (ICAs), being very rare bilateral aneurysms. This report describes a very unusual case of fusiform aneurysms of both ICAs in a Caucasian NF1 patient, with a new pathogenic intragenic heterozygous deletion of the NF1 gene, presenting at age 22 years with Tolosa–Hunt syndrome, because of partial thrombosis of the left giant intracavernous aneurysm. Medical treatment with anticoagulant therapy allowed a good outcome for the patient. In conclusion, early identification of cerebral arteriopathy in NF1 and close follow-up of its progression by neuroimaging may lead to early medical or surgical intervention and prevention of significant neurologic complications. PMID:24476631

  12. Investigation of the Hemodynamic Effect of Stent Wires on Renal Arteries in Patients with Abdominal Aortic Aneurysms Treated with Suprarenal Stent-Grafts

    SciTech Connect

    Sun Zhonghua; Chaichana, Thanapong

    2009-07-15

    The purpose of the study was to investigate the hemodynamic effect of stent struts (wires) on renal arteries in patients with abdominal aortic aneurysms (AAAs) treated with suprarenal stent-grafts. Two sample patients with AAA undergoing multislice CT angiography pre- and postsuprarenal fixation of stent-grafts were selected for inclusion in the study. Eight juxtarenal models focusing on the renal arteries were generated from the multislice CT datasets. Four types of configurations of stent wires crossing the renal artery ostium were simulated in the segmented aorta models: a single wire crossing centrally, a single wire crossing peripherally, a V-shaped wire crossing centrally, and multiple wires crossing peripherally. The blood flow pattern, flow velocity, wall pressure, and wall shear stress at the renal arteries pre- and post-stent-grafting were analyzed and compared using a two-way fluid structure interaction analysis. The stent wire thickness was simulated with a diameter of 0.4, 1.0, and 2.0 mm, and hemodynamic analysis was performed at different cardiac cycles. The interference of stent wires with renal blood flow was mainly determined by the thickness of stent wires and the type of configuration of stent wires crossing the renal ostium. The flow velocity was reduced by 20-30% in most of the situations when the stent wire thickness increased to 1.0 and 2.0 mm. Of the four types of configuration, the single wire crossing centrally resulted in the highest reduction of flow velocity, ranging from 21% to 28.9% among three different wire thicknesses. Wall shear stress was also dependent on the wire thickness, which decreased significantly when the wire thickness reached 1.0 and 2.0 mm. In conclusion, our preliminary study showed that the hemodynamic effect of suprarenal stent wires in patients with AAA treated with suprarenal stent-grafts was determined by the thickness of suprarenal stent wires. Research findings in our study are useful for follow-up of

  13. [A Case of Ruptured Internal Carotid-Posterior Communicating Artery Aneurysm Associated with Acute Subdural Hematoma, Extending from the Interhemispheric Space to the Posterior Fossa].

    PubMed

    Otsuka, Hiroaki; Fukuda, Yuhtaka; Yoshimura, Shouta; Somagawa, Chika; Hiu, Takeshi; Ono, Tomonori; Ushijima, Ryujirou; Toda, Keisuke; Tsutsumi, Keisuke

    2016-06-01

    A 69-year-old woman was admitted to our hospital because of a sudden severe headache without a history of head trauma. CT and MRI revealed an acute subdural hematoma (ASDH) extending from the right interhemispheric space to the posterior fossa bilaterally, with a small amount of subarachnoid hemorrhage that was predominantly localized to the left side of the basal cistern. CT angiogram demonstrated a long protruding ruptured aneurysm at the junction of the right internal carotid and posterior communicating arteries (IC/PC AN) with a posteroinferior projection, associated with a small bleb located near the tentorial edge close to the ipsilateral posterior clinoid process, for which she received clipping surgery. Though rare, IC/PC AN could cause pure or nearly pure ASDH in the above-mentioned distribution. Therefore, in patients with such ASDH, especially without a history of head injury or precise information regarding the situation at the time of onset, urgent imaging evaluation and early intervention are essential to prevent devastating re-rupture events.

  14. Risk factors for neurological worsening and symptomatic watershed infarction in internal carotid artery aneurysm treated by extracranial-intracranial bypass using radial artery graft.

    PubMed

    Matsukawa, Hidetoshi; Tanikawa, Rokuya; Kamiyama, Hiroyasu; Tsuboi, Toshiyuki; Noda, Kosumo; Ota, Nakao; Miyata, Shiro; Oda, Jumpei; Takeda, Rihee; Tokuda, Sadahisa; Kamada, Kyousuke

    2016-08-01

    OBJECT The revascularization technique, including bypass created using the external carotid artery (ECA), radial artery (RA), and M2 portion of middle cerebral artery (MCA), has remained indispensable for treatment of complex aneurysms. To date, it remains unknown whether diameters of the RA, superficial temporal artery (STA), and C2 portion of the internal carotid artery (ICA) and intraoperative MCA blood pressure have influences on the outcome and the symptomatic watershed infarction (WI). The aim of the present study was to evaluate the factors for the symptomatic WI and neurological worsening in patients treated by ECA-RA-M2 bypass for complex ICA aneurysm with therapeutic ICA occlusion. METHODS The authors measured the sizes of vessels (RA, C2, M2, and STA) and intraoperative MCA blood pressure (initial, after ICA occlusion, and after releasing the RA graft bypass) in 37 patients. Symptomatic WI was defined as presence of the following: postoperative new neurological deficits, WI on postoperative diffusion-weighted imaging, and ipsilateral cerebral blood flow reduction on SPECT. Neurological worsening was defined as the increase in 1 or more modified Rankin Scale scores. First, the authors performed receiver operating characteristic curve analysis for continuous variables and the binary end point of the symptomatic WI. The clinical, radiological, and physiological characteristics of patients with and without the symptomatic WI were compared using the log-rank test. Then, the authors compared the variables between patients with and without neurological worsening at discharge and at the 12-month follow-up examination or last hospital visit. RESULTS Symptomatic WI was observed in 2 (5.4%) patients. The mean MCA pressure after releasing the RA graft (< 55 mm Hg; p = 0.017), mean (MCA pressure after releasing the RA graft)/(initial MCA pressure) (< 0.70 mm Hg; p = 0.032), and mean cross-sectional area ratio ([RA/C2 diameter](2) < 0.40 mm [p < 0.0001] and [STA/C2

  15. Subject-specific modeling of intracranial aneurysms

    NASA Astrophysics Data System (ADS)

    Cebral, Juan R.; Hernandez, Monica; Frangi, Alejandro; Putman, Christopher; Pergolizzi, Richard; Burgess, James

    2004-04-01

    Characterization of the blood flow patterns in cerebral aneurysms is important to explore possible correlations between the hemodynamics conditions and the morphology, location, type and risk of rupture of intracranial aneurysms. For this purpose, realistic patient-specific models are constructed from computed tomography angiography and 3D rotational angiography image data. Visualizations of the distribution of hemodynamics forces on the aneurysm walls as well as the intra-aneurysmal flow patterns are presented for a number of cerebral aneurysms of different sizes, types and locations. The numerical models indicate that there are different classes of intra-aneurysmal flow patterns, that may carry different risks of rupture.

  16. New technique for the preservation of the left common carotid artery in zone 2a endovascular repair of thoracic aortic aneurysm.

    PubMed

    Juszkat, Robert; Kulesza, Jerzy; Zarzecka, Anna; Jemielity, Marek; Staniszewski, Ryszard; Majewski, Wacław

    2011-02-01

    To describe a technique for the preservation of the left common carotid artery (CCA) in zone 2 endovascular repair of thoracic aortic aneurysm. This technique involves the placement of a guide wire into the left CCA via the right brachial artery before stent graft deployment to enable precise visualization and protection of the left CCA during the whole procedure. Of the 107 patients with thoracic endovascular aortic repair in our study, 32 (30%) had the left subclavian artery intentionally covered (landing zone 2). Eight (25%) of those 32 had landing zone 2a-the segment distally the origin of the left CCA, halfway between the origin of the left CCA and the left subclavian artery. In all patients, a guide wire was positioned into the left CCA via the right brachial artery before stent graft deployment. It is a retrospective study in design. In seven patients, stent grafts were positioned precisely. In the remaining patient, the positioning was imprecise; the origin of the left CCA was partially covered by the graft. A stent was implanted into the left CCA to restore the flow into the vessel. All procedures were performed successfully. The technique of placing a guide wire into the left CCA via the right brachial artery before stent graft deployment is a safe and effective method that enables the precise visualization of the left CCA during the whole procedure. Moreover, in case of inadvertent complete or partial coverage of the origin of the left CCA, it supplies safe and quick access to the artery for stent implantation.

  17. Paraclinoid aneurysm concealed by sphenoid wing meningioma.

    PubMed

    Petrecca, Kevin; Sirhan, Denis

    2009-02-01

    The coexistence of brain tumours and aneurysms is rare. In all previously reported cases the aneurysm was detectable by angiography. We report here a case in which a paraclinoid internal carotid artery aneurysm was coexistent and concealed from angiographic detection by an adjacent parasellar meningioma.

  18. First Case of Endovascular Treatment of Ruptured Internal Carotid Artery Aneurysm Using Stent Assisted Coiling at the Department of Neurosurgery in Skopje.

    PubMed

    Filipce, Venko; Caparoski, Aleksandar; Milosevic, Zoran

    2015-01-01

    The management of intracranial aneurysms has changed dramatically in recent years. The science and technology advancement have resulted in new therapeutic options for their treatment. There is an increased interest among neurosurgeons to perform endovascular procedures for intracranial aneurysms. This has become a part of the neurosurgical residency in the US. We are presenting our first experience of ruptured aneurysm coiling using stent assisted technique.

  19. Aneurysms of medium-sized arteries in Marfan syndrome.

    PubMed

    Awais, Mazen; Williams, David M; Deeb, G Michael; Shea, Michael J

    2013-11-01

    Marfan syndrome is a relatively common connective tissue disorder that causes skin, ocular, skeletal, and cardiovascular abnormalities. High morbidity and mortality occur with aortic aneurysm and dissection. Other large-artery aneurysms, including carotid, subclavian, and iliac artery aneurysms, have also been associated with Marfan syndrome. It is not clear whether small- to medium-sized artery aneurysms are associated with Marfan syndrome. This report describes 4 patients with Marfan syndrome who have associated small- to medium-sized artery aneurysms with several complications. Additional investigations are needed to determine whether Marfan syndrome can cause small- to medium-sized artery aneurysms and how patients with these aneurysms should be treated.

  20. Nocardia abscessus-related intracranial aneurysm of the internal carotid artery with associated brain abscess: A case report and review of the literature.

    PubMed

    Farran, Yvette; Antony, Suresh

    2016-01-01

    Nocardia infections primarily begin in the lungs and spread hematogenously to other sites in the body. Thus, a Nocardia brain abscess is not a completely uncommon occurrence. However, a Nocardia brain abscess complicated by a middle cerebral artery and infectious intracranial aneurysm is a very rare clinical entity. We present a case of an infectious intracranial aneurysm with an associated Nocardia brain abscess that required surgical intervention and resection. The patient was an immunocompetent 60-year-old male who presented with a chief complaint of headache and was found to have an infected intracranial aneurysm and cerebral abscess. He underwent drainage of the abscess with subsequent resection of the infected aneurysm. Cultures from both the blood vessel and brain tissue grew Nocardia abscessus. He was successfully treated with 6 weeks of ceftriaxone and high-dose trimethoprim-sulfamethoxazole. Infectious intracranial aneurysms of the brain caused by Nocardia are rare occurrences, and only a single previous case has been described in the literature. The outcomes of this condition can be catastrophic if it is not treated with a combination of surgery and intravenous antibiotics. The guidelines for the management of this infection are not well defined at this time.

  1. Cerebral Aneurysms

    MedlinePlus

    ... treatment prevents repeat aneurysm rupture by placing a metal clip at the base of the aneurysm. Individuals ... the aneurysm, where it is used to insert metal coils that induce clot formation within the aneurysm. × ...

  2. Giant Serpentine Aneurysm of the Middle Cerebral Artery

    PubMed Central

    Lee, Seung Joo; Kwun, Byung Duk; Kim, Chang Jin

    2010-01-01

    Giant serpentine aneurysms are rare and have distinct angiographic findings. The rarity, large size, complex anatomy and hemodynamic characteristics of giant serpentine aneurysms make treatment difficult. We report a case of a giant serpentine aneurysm of the right middle cerebral artery (MCA) that presented as headache. Treatment involved a superficial temporal artery (STA)-MCA bypass followed by aneurysm resection. The patient was discharged without neurological deficits, and early and late follow-up angiography disclosed successful removal of the aneurysm and a patent bypass graft. We conclude that STA-MCA bypass and aneurysm excision is a successful treatment method for a giant serpentine aneurysm. PMID:20856671

  3. Carotid Ultrasound

    MedlinePlus

    ... this page from the NHLBI on Twitter. Carotid Ultrasound Also known as carotid duplex. Carotid ultrasound is a painless imaging test that uses high- ... of your carotid arteries. This test uses an ultrasound machine, which includes a computer, a screen, and ...

  4. In vitro investigation of contrast flow jet timing in patient-specific intracranial aneurysms

    PubMed Central

    Desai, Virendra R.; Britz, Garvin W.

    2016-01-01

    Background The direction and magnitude of intra-aneurysmal flow jet are significant risk factors of subarachnoid hemorrhage, and the change of flow jet during an endovascular procedure has been used for prediction of aneurysm occlusion or whether an additional flow diverter (FD) is warranted. However, evaluation of flow jets is often unreliable due to a large variation of flow jet on the digital subtraction angiograms, and this flow pattern variation may result in incorrect clinical diagnosis Therefore, factors contributing to the variation in flow jet are examined at an in vitro setting, and the findings can help us to understand the nature of flow jet and devise a better plan to quantify the aneurysmal hemodynamics accurately. Methods Intra-aneurysmal flows in three patient-specific aneurysms between 11 and 25 mm were investigated in vitro, and a FD was deployed in each aneurysm model. X-ray imaging of these models were performed at injection rates between 0.2 and 2 mL/s. Pulsatile blood pump and aneurysm model were imaged together to determine the timing of flow jet. Results The contrast bolus arrives at the aneurysm early at high contrast injection rates. The flow patterns with slow injection rates exhibit strong inertia that is associated with the systole flow. Flow jets arrive at the aneurysms at the peak systole when the bolus is injected at 0.2 mL/s. The contrast-to-signal ratio is the highest at the injection rate of 0.5 mL/s. Effect of flow diversion can only be assessed at an injection rate greater than 0.5 mL/s. Conclusions Intra-aneurysmal flow jet is highly dependent on the injection rate of the contrast agent. For the internal carotid artery (ICA) aneurysms, the systolic flows can be visualized at slow injection rates (<0.5 mL/s), while the diastolic flow jets are visible at higher injection rates (>1 mL/s). Dependence of flow jet on the contrast injection rate has serious clinical implications and needs to be considered during diagnostic procedures

  5. [A case of successful treatment of concomitant ruptured intracranial aneurysm and visceral aneurysm].

    PubMed

    Diogo, Cláudia; Baltazar, José; Fernandes, Mário

    2012-01-01

    The association between intracranial and visceral aneurysms is very rare, with a bad prognosis. The rupture usually appears in the Emergency Room, and it implies an immediate treatment. We describe the case of a woman with rupture of an anterior communicant artery aneurysm and rupture of a pancreatic duodenal artery aneurysm. The actuation of all specialties allowed the direct surgical treatment of the visceral aneurysm, without the aggravation of the cerebral hemorrhage that the eventual Aorta Artery clamping could provoke. The maintenance of the hemodynamic stability was essential for the posterior treatment of the intracranial aneurysm.

  6. Statins and cerebral hemodynamics

    PubMed Central

    Giannopoulos, Sotirios; Katsanos, Aristeidis H; Tsivgoulis, Georgios; Marshall, Randolph S

    2012-01-01

    HMG-CoA reductase inhibitors (statins) are associated with improved stroke outcome. This observation has been attributed in part to the palliative effect of statins on cerebral hemodynamics and cerebral autoregulation (CA), which are mediated mainly through the upregulation of endothelium nitric oxide synthase (eNOS). Several animal studies indicate that statin pretreatment enhances cerebral blood flow after ischemic stroke, although this finding is not further supported in clinical settings. Cerebral vasomotor reactivity, however, is significantly improved after long-term statin administration in most patients with severe small vessel disease, aneurysmal subarachnoid hemorrhage, or impaired baseline CA. PMID:22929438

  7. Microsurgical treatment of ophthalmic segment aneurysms.

    PubMed

    Gross, Bradley A; Du, Rose

    2013-08-01

    Ophthalmic segment aneurysms refer to superior hypophyseal artery aneurysms, true ophthalmic artery aneurysms, and their dorsal variant. Indications for treatment of these aneurysms include concerning morphological features, large size, visual loss, or rupture. Although narrow-necked aneurysms are ideal endovascular targets, more complex and larger lesions necessitating adjunctive stent or flow-diversion techniques may be suitably treated with long-lasting, effective clip ligation instead. This is particularly relevant in the consideration of ruptured ophthalmic segment aneurysms. This article provides a depiction of microsurgical treatment of ophthalmic segment aneurysms with an accompanying video demonstration. Emphasis is placed on microsurgical anatomy, the intradural anterior clinoidectomy and clipping technique. The intradural anterior clinoidectomy, demonstrated in detail in our Supplementary video, provides significant added exposure of the ophthalmic segment of the internal carotid artery, allowing for improved aneurysm visualization. In the management of superior hypophyseal artery aneurysms, emphasis is placed on identifying and preserving superior hypophyseal artery perforators, using serial fenestrated straight clips rather than a single right-angled fenestrated clip to obliterate the aneurysm. Post-clipping indocyanine green dye angiography is a crucial tool to confirm aneurysm obliteration and the preservation of the parent vasculature and adjacent superior hypophyseal artery perforators. With careful attention to the nuances of microsurgical clipping of ophthalmic segment aneurysms, rewarding results can be obtained.

  8. Carotid barochemoreceptor pathological findings regarding carotid plaque status and aging

    PubMed Central

    Milei, José; Lavezzi, Anna M; Bruni, Barbara; Grana, Daniel R; Azzato, Francisco; Matturri, Luigi

    2009-01-01

    BACKGROUND: Carotid barochemoreceptor pathological lesions have been studied in animals, but few human necropsies have been performed. Therefore, data rely on case patients following surgery, radiotherapy and carotid endarterectomy. Almost no data are available regarding whether the effect of aging prevails over pathological conditions, despite the classic description that glomic fibrosis increases with age. OBJECTIVE: To morphometrically characterize the alterations of the carotid barochemoreceptors and their supplying arteries. METHODS: Patients (n=23) who had suffered and died from stroke, with and without complicated internal carotid atheromatosis, were divided by age (group 1: older than 80 years; group 2: 65 to 80 years; and group 3: younger than 65 years). Carotid segments were obtained at autopsy. The specimens were stained for light microscopy and immunohistochemistry. RESULTS: Carotid glomus presented from moderate-to-severe atrophy and fibrosis. A focal decrease in vascularization (CD34-positive) of the glomus (greater than 50%) was observed in areas of atrophy and fibrosis. Damaged nerve endings (S100 protein-positive) were observed at the media of the carotid sinus. Morphometric data showed no differences between groups for glomus area, number of type 1 and 2 cells, and the wall to lumen arteriole ratio. No statistical differences were demonstrated in the pathological findings of the carotid glomus when comparing complicated with noncomplicated plaques or age groups. CONCLUSION: Severe carotid chemoreceptor damage exists in patients who have died from stroke and suffered from carotid atheromatosis. These findings were independent from aging and plaque type. However, damage was correlated with a marked narrowing of the supplying arterioles as a consequence of hemodynamic and/or metabolic alterations (dyslipidemia, diabetes). PMID:19148350

  9. Spontaneous regression of intracranial aneurysm following remote ruptured aneurysm treatment with pipeline stent assisted coiling.

    PubMed

    Tsimpas, Asterios; Ashley, William W; Germanwala, Anand V

    2016-10-01

    Spontaneous aneurysm regression is a rare phenomenon. We present the interesting case of a 54-year-old woman who was admitted with a Hunt/Hess grade IV, Fisher grade III subarachnoid hemorrhage and multiple intracranial aneurysms. She was treated with coiling of the largest paraclinoid aneurysm and placement of a flow diverting pipeline embolization device that covered all internal carotid artery (ICA) aneurysms. A follow-up angiogram at 6 months showed remodeling of the ICA with complete obliteration of all treated aneurysms. A distant, untreated, right frontal M2 aneurysm regressed spontaneously, after the flow was diverted away from it with the stent. The literature is reviewed, and potential pathophysiological mechanisms leading to aneurysm regression are discussed.

  10. Spontaneous regression of intracranial aneurysm following remote ruptured aneurysm treatment with pipeline stent assisted coiling.

    PubMed

    Tsimpas, Asterios; Ashley, William W; Germanwala, Anand V

    2015-08-13

    Spontaneous aneurysm regression is a rare phenomenon. We present the interesting case of a 54-year-old woman who was admitted with a Hunt/Hess grade IV, Fisher grade III subarachnoid hemorrhage and multiple intracranial aneurysms. She was treated with coiling of the largest paraclinoid aneurysm and placement of a flow diverting pipeline embolization device that covered all internal carotid artery (ICA) aneurysms. A follow-up angiogram at 6 months showed remodeling of the ICA with complete obliteration of all treated aneurysms. A distant, untreated, right frontal M2 aneurysm regressed spontaneously, after the flow was diverted away from it with the stent. The literature is reviewed, and potential pathophysiological mechanisms leading to aneurysm regression are discussed.

  11. Headache attributed to unruptured saccular aneurysm, mimicking hemicrania continua.

    PubMed

    Vikelis, Michail; Xifaras, Michail; Magoufis, Georgios; Gekas, Georgios; Mitsikostas, Dimos Dimitrios

    2005-06-01

    Unruptured cerebral arterial aneurysms most often remain asymptomatic, but they may cause headache or other symptoms or signs. We describe herewith a case of headache attributed to an unruptured internal carotid artery aneurysm, clearly mimicking the phenotype of hemicrania continua. Potential pathophysiological explanations and recommendations for recognition of similar cases are discussed.

  12. Idiopathic Lingual Artery Aneurysm: CT Findings and Endovascular Therapy

    PubMed Central

    Brindle, R.S.; Fernandez, P.M.; Sattenberg, R.J.; Flynn, M.B.; Heidenreich, J.O.

    2010-01-01

    Summary We describe a 65-year-old woman with an asymptomatic idiopathic lingual artery aneurysm which is suspected to be congenital. We review the literature on external carotid artery branch aneurysms, diagnostic evaluation and discuss treatment options for the various types and the specific chosen in the case presented. PMID:20377988

  13. Observation of cerebral aneurysm wall thickness using intraoperative microscopy: clinical and morphological analysis of translucent aneurysm.

    PubMed

    Song, Jihye; Park, Jung Eon; Kim, Hyoung Ryoul; Shin, Yong Sam

    2015-06-01

    Intracranial aneurysms suffer various interactions between hemodynamics and pathobiology, and rupture when this balance disrupted. Aneurysm wall morphology is a result of these interactions and reflects the quality of the maturation. However, it is a poorly documented in previous studies. The purpose of this study is to observe aneurysm wall thickness and describe the characteristics of translucent aneurysm by analyzing clinical and morphological parameters. 253 consecutive patients who underwent clipping surgery in a single institute were retrospectively analyzed. Only middle cerebral artery aneurysms (MCA) which exposed most part of the dome during surgery were included. Aneurysms were categorized based on intraoperative video findings. Aneurysms more than 90 % of super-thin dome and any aneurysms with entirely super-thin-walled daughter sac were defined as translucent aneurysm. A total of 110 consecutive patients with 116 unruptured MCA aneurysms were included. Ninety-two aneurysms (79.3 %) were assigned to the not-translucent group and 24 (20.7 %) to the translucent group. The relative proportion of translucent aneurysm in each age group was highest at ages 50-59 years and absent at ages 30-39 and 70-79 years. There was a trend that translucent aneurysms were smaller in size (p = 0.019). Multivariate logistic analysis showed that translucent aneurysm was strongly correlated with height <3 mm (p = 0.003). We demonstrated that the translucent aneurysms were smaller in size and the aneurysm height <3 mm was related. These results may provide information in determining treatment strategies in patients with small size aneurysm.

  14. Role of Kruppel-like Factor 2 in Intracranial Aneurysm of the Rabbit Model.

    PubMed

    Wu, X; Zhang, J; Huang, Q; Yang, P; Chen, J; Liu, J

    2015-11-08

    We investigated expression of Kruppel—like factor 2 (KLF2) and its correlation with basilar artery blood flow rate in the hemodynamically induced aneurysm model built by different methods. New Zealand rabbits were randomly divided into sham—operated group, unilateral ligation of common carotid artery (CCA) group (UL group) and bilateral ligation of CCA group (BL group). Rabbits were cervix—cut to expose the arteries without ligation (sham group), with right—side ligation (UL group) and bilateral ligation (BL group), respectively. Skull Doppler ultrasound was used to measure basilar artery blood flow rate in each group at week 1, 2, 3, or 4 separately (n=6 for each time point). The animals were killed after the measurements. At each time point, 6 basilar artery bifurcates from each group were collected and sent for staining (HE, EVG, Masson and KLF2 immunohistochemistry staining), while another 6 basilar artery bifurcates were processed with KLF2 Western blotting. Results showed that the average blood flow rate did not change significantly among the 4 time points in the Sham group, but it was insignificantly smaller compared to the UL group. The average blood flow rate in the BL group was significantly higher than that in the other two groups. Pathological tests showed that according to the aneurysm evaluation criteria, the basilar arteries in the Sham group had smooth tip lumina, complete endothelial cells, complete internal elastic membranes, but no fracture, thinning or aneurysm formation. Only 1 of 24 rabbits in the UL group had slight bulges in the tip of basilar artery, though not very severe. Twelve rabbits in the BL group had aneurysmal bulges, significantly different from the other two groups. KLF2 protein expression was not changed significantly with time in the Sham group, but increased slightly with time in the UL group. KLF2 protein expression in the BL group increased significantly only after 1 week and then maintained a high level

  15. Flow Instability and Wall Shear Stress Ocillation in Intracranial Aneurysms

    NASA Astrophysics Data System (ADS)

    Baek, Hyoungsu; Jayamaran, Mahesh; Richardson, Peter; Karniadakis, George

    2009-11-01

    We investigate the flow dynamics and oscillatory behavior of wall shear stress (WSS) vectors in intracranial aneurysms using high-order spectral/hp simulations. We analyze four patient- specific internal carotid arteries laden with aneurysms of different characteristics : a wide-necked saccular aneurysm, a hemisphere-shaped aneurysm, a narrower-necked saccular aneurysm, and a case with two adjacent saccular aneurysms. Simulations show that the pulsatile flow in aneurysms may be subject to a hydrodynamic instability during the decelerating systolic phase resulting in a high-frequency oscillation in the range of 30-50 Hz. When the aneurysmal flow becomes unstable, both the magnitude and the directions of WSS vectors fluctuate. In particular, the WSS vectors around the flow impingement region exhibit significant spatial and temporal changes in direction as well as in magnitude.

  16. Percutaneous Injection of Lidocaine Within the Carotid Body Area in Carotid Artery Stenting: An 'Old-New' Technique

    SciTech Connect

    Mourikis, Dimitrios; Chatoupis, Konstantinos; Katsenis, Konstantinos; Vlahos, Lampros; Chatziioannou, Achilles

    2008-07-15

    Severe bradycardia is a common untoward effect during balloon angioplasty when performing carotid artery stenting. Therefore atropine injection even before dilatation and the presence of an anesthesiologist are advocated in all patients. In the surgical literature, injection of a local anesthetic agent into the carotid sinus before carotid endarterectomy was performed in an attempt to ameliorate perioperative hemodynamic instability. This study was undertaken to test the hypothesis that percutaneous infiltration of the carotid sinus with local anesthetic immediately before balloon dilatation reduces bradycardia and ameliorates the need for atropine injection or the presence of an anesthesiologist. Infiltration of the carotid sinus with 5 ml of 1% lidocaine, 3 min before dilatation, was performed in 30 consecutive patients. No one exhibited any significant rhythm change that required atropine injection. The anesthesiologist did not face any hemodynamic instability during the carotid artery stenting procedure.

  17. Aneurysm in the brain

    MedlinePlus

    Aneurysm - cerebral; Cerebral aneurysm; Aneurysm - intracranial ... July 19, 2016. Szeder V, Tateshima S, Duckwiler GR. Intracranial aneurysms and subarachnoid hemorrhage. In: Daroff RB, Jankovic J, ...

  18. PIV-measured versus CFD-predicted flow dynamics in anatomically realistic cerebral aneurysm models.

    PubMed

    Ford, Matthew D; Nikolov, Hristo N; Milner, Jaques S; Lownie, Stephen P; Demont, Edwin M; Kalata, Wojciech; Loth, Francis; Holdsworth, David W; Steinman, David A

    2008-04-01

    Computational fluid dynamics (CFD) modeling of nominally patient-specific cerebral aneurysms is increasingly being used as a research tool to further understand the development, prognosis, and treatment of brain aneurysms. We have previously developed virtual angiography to indirectly validate CFD-predicted gross flow dynamics against the routinely acquired digital subtraction angiograms. Toward a more direct validation, here we compare detailed, CFD-predicted velocity fields against those measured using particle imaging velocimetry (PIV). Two anatomically realistic flow-through phantoms, one a giant internal carotid artery (ICA) aneurysm and the other a basilar artery (BA) tip aneurysm, were constructed of a clear silicone elastomer. The phantoms were placed within a computer-controlled flow loop, programed with representative flow rate waveforms. PIV images were collected on several anterior-posterior (AP) and lateral (LAT) planes. CFD simulations were then carried out using a well-validated, in-house solver, based on micro-CT reconstructions of the geometries of the flow-through phantoms and inlet/outlet boundary conditions derived from flow rates measured during the PIV experiments. PIV and CFD results from the central AP plane of the ICA aneurysm showed a large stable vortex throughout the cardiac cycle. Complex vortex dynamics, captured by PIV and CFD, persisted throughout the cardiac cycle on the central LAT plane. Velocity vector fields showed good overall agreement. For the BA, aneurysm agreement was more compelling, with both PIV and CFD similarly resolving the dynamics of counter-rotating vortices on both AP and LAT planes. Despite the imposition of periodic flow boundary conditions for the CFD simulations, cycle-to-cycle fluctuations were evident in the BA aneurysm simulations, which agreed well, in terms of both amplitudes and spatial distributions, with cycle-to-cycle fluctuations measured by PIV in the same geometry. The overall good agreement

  19. Reconstructive surgery for segmental arterial mediolysis involving both the internal carotid artery and visceral arteries.

    PubMed

    Obara, Hideaki; Matsumoto, Kenji; Narimatsu, Yoshiaki; Sugiura, Hitoshi; Kitajima, Masaki; Kakefuda, Toshihiro

    2006-03-01

    Segmental arterial mediolysis (SAM) is a rare, nonatherosclerotic, noninflammatory arteriopathy. A 52-year-old man with sudden hemiparesis of the right side was found to have an aneurysm of the left internal carotid artery and concomitant multiple aneurysms of the extrahepatic, celiac, and superior mesenteric arteries. Reconstructive operations using autologous vein graft were performed to treat the aneurysms. The histopathology analyses of resected arterial and aneurysmal specimens showed characteristics consistent with SAM. To our knowledge, a successfully treated case of SAM affecting both the carotid artery and visceral arteries has not previously been described.

  20. Surgical repair of a giant aneurysm of the right subclavian artery.

    PubMed

    Spinelli, Francesco; Stilo, Francesco; Benedetto, Filippo; Lentini, Salvatore

    2010-05-01

    Giant isolated subclavian aneurysm is a rare disease. We report a case of a 66-year-old lady, with a proximal intrathoracic true aneurysm of the right subclavian artery. Due to the absence of a proximal neck, and for the relevant tortuosity of the vessels, we decided to approach the aneurysm through a median sternotomy. The aneurysm was excluded and opened. Then, we performed a direct subclavian-carotid transposition. The postoperative course was uneventful.

  1. [A case of bilateral infraoptic course of ACA associated with multiple cerebral artery aneurysms].

    PubMed

    Ogura, K; Hasegawa, K; Kobayashi, T; Kohno, M; Hondo, H

    1998-06-01

    Infraoptic course of anterior cerebral artery (ACA) is a rare cerebral vascular anomaly frequently associated with intracranial aneurysm. A 58-year-old woman suffered, subarachnoid hemorrhage due to aneurysmal rupture. Carotid angiography revealed multiple aneurysms and bilateral infraoptic course of ACA. Usual A1 segments were not visualized on both sides. These findings were also confirmed by craniotomy. Only 46 cases have been reported including ours. In this paper, we reviewed previously reported cases and the cause of aneurysm formation was discussed.

  2. Brain Aneurysm

    MedlinePlus

    ... tests don't provide enough information. Screening for brain aneurysms The use of imaging tests to screen ... and occupational therapy to relearn skills. Treating unruptured brain aneurysms Surgical clipping or endovascular coiling can be ...

  3. Aortic Aneurysm

    MedlinePlus

    ... these occur in the part of the aorta running through the chest Abdominal aortic aneurysms (AAA) - these occur in the part of the aorta running through the abdomen Most aneurysms are found during ...

  4. Brain Aneurysm

    MedlinePlus

    A brain aneurysm is an abnormal bulge or "ballooning" in the wall of an artery in the brain. They are sometimes called berry aneurysms because they ... often the size of a small berry. Most brain aneurysms produce no symptoms until they become large, ...

  5. Extended use of endovascular aneurysm sealing for ruptured abdominal aortic aneurysms.

    PubMed

    Böckler, Dittmar; Holden, Andrew; Krievins, Dainis; de Vries, Jean-Paul P M; Peters, Andreas S; Geisbüsch, Philipp; Reijnen, Michel

    2016-09-01

    Endovascular repair of abdominal aortic aneurysms (EVAR) is now an established treatment modality for suitable patients presenting with aneurysm rupture. EVAR for ruptured aneurysms reduces transfusion, mechanical ventilation, intensive care. and hospital stay when compared with open surgery. In the emergency setting, however, EVAR is limited by low applicability due to adverse clinical or anatomical characteristics and increased need for reintervention. In addition, ongoing bleeding from aortic side branches post-EVAR can cause hemodynamic instability, larger hematomas, and abdominal compartment syndrome. Endovascular aneurysm sealing, based on polymer filling of the aneurysm, has the potential to overcome some of the limitations of EVAR for ruptured aneurysms and to improve outcomes. Recent literature suggests that endovascular aneurysm sealing can be performed with early mortality similar to that of EVAR for ruptured aortic aneurysms, but experience is limited to a few centers and a small number of patients. The addition of chimney grafts can increase the applicability of endovascular aneurysm sealing in order to treat short-neck and juxtarenal aneurysms as an alternative to fenestrated endografts. Further evaluation of the technique, with larger longitudinal studies, is necessary before advocating wider implementation of endovascular aneurysm sealing in the emergency setting.

  6. Carotid Endarterectomy

    MedlinePlus

    ... is not a cure. Your arteries can become blocked again if your underlying condition, such as high ... or cut, on your neck to expose the blocked section of the carotid artery. Your surgeon will ...

  7. Carotid duplex

    MedlinePlus

    ... moved around your neck. The pressure should not cause any pain. You may also hear a "whooshing" sound. This is normal. ... clotting (thrombosis) Narrowing in the arteries (stenosis) Other ... an abnormal sound called a bruit over the carotid neck arteries. ...

  8. Dynamics of collateral circulation in progressive asymptomatic carotid disease.

    PubMed

    Moll, F L; Eikelboom, B C; Vermeulen, F E; van Lier, H J; Schulte, B P

    1986-03-01

    Inadequacy of collateral arterial flow is the major risk factor for hemispheric infarction in association with spontaneous occlusion of the ipsilateral carotid artery. This prospective study was designed to measure the adaptation of collateral cerebral circulation through the circle of Willis in patients in whom a unilateral carotid stenosis of hemodynamic consequence develops asymptomatically. The collateral cerebral potential is assessed by ocular pneumoplethysmography (OPG) during proximal common carotid artery compression, measuring the collateral ophthalmic artery pressure (COAP). During an average follow-up of almost 3 years (maximum more than 7 years), 45 patients showed asymptomatic development of a unilateral hemodynamically significant carotid stenosis according to OPG evidence. In these patients the mean index COAP/brachial artery pressure did not change on the side of stenosis progression (p greater than 0.05). The developed carotid stenosis had only reduced collateral circulation to the contralateral hemisphere. The risk of inadequate collateral cerebral circulation remained during progression of asymptomatic extracranial arterial obstructive disease.

  9. Image-based analysis of blood flow modification in stented aneurysms

    NASA Astrophysics Data System (ADS)

    Cebral, Juan; Mut, Fernando; Appanaboyina, Sunil; Löhner, Rainald; Miranda, Carlos; Escrivano, Esteban; Lylyk, Pedro; Putman, Christopher

    2009-02-01

    Currently there is increased interest in the use of stents as flow diverters for the treatment of intracranial aneurysms, especially wide necked aneurysms that are difficult to treat by coil embolization or surgical clipping. This paper presents image-based patient-specific computational models of the hemodynamics in cerebral aneurysms before and after treatment with a stent alone, with the goal of better understanding the hemodynamic effects of these devices and their relation to the outcome of the procedures. Stenting of cerebral aneurysms is a feasible endovascular treatment option for aneurysms with wide necks that are difficult to treat with coils or by surgical clipping. However, this requires stents that are capable of substantially modifying the intra-aneurysmal flow pattern in order to cause thrombosis of the aneurysm. The results presented in this paper show that the studied stent was able to change significantly the hemodynamic characteristics of the aneurysm. In addition, it was shown that patient-specific computational models constructed from medical images are capable of realistically representing the in vivo hemodynamic characteristics observed during conventional angiography examinations before and after stenting. This indicates that these models can be used to better understand the effects of different stent designs and to predict the alteration in the hemodynamic pattern of a given aneurysm produced by a given flow diverter. This is important for improving current design of flow diverting devices and patient treatment plans.

  10. Suggested connections between risk factors of intracranial aneurysms: a review.

    PubMed

    Cebral, Juan R; Raschi, Marcelo

    2013-07-01

    The purpose of this article is to review studies of aneurysm risk factors and the suggested hypotheses that connect the different risk factors and the underlying mechanisms governing the aneurysm natural history. The result of this work suggests that at the center of aneurysm evolution there is a cycle of wall degeneration and weakening in response to changing hemodynamic loading and biomechanic stress. This progressive wall degradation drives the geometrical evolution of the aneurysm until it stabilizes or ruptures. Risk factors such as location, genetics, smoking, co-morbidities, and hypertension seem to affect different components of this cycle. However, details of these interactions or their relative importance are still not clearly understood.

  11. Intracranial Non-traumatic Aneurysms in Children and Adolescents

    PubMed Central

    Sorteberg, Angelika; Dahlberg, Daniel

    2013-01-01

    An intracranial aneurysm in a child or adolescent is a rare, but potentially devastating condition. As little as approximately 1200 cases are reported between 1939 and 2011, with many of the reports presenting diverting results. There is consensus, though, in that pediatric aneurysms represent a pathophysiological entity different from their adult counterparts. In children, there is a male predominance. About two-thirds of pediatric intracranial aneurysms become symptomatic with hemorrhage and the rate of re-hemorrhage is higher than in adults. The rate of hemorrhage from an intracranial aneurysm peaks in girls around menarche. The most common aneurysm site in children is the internal carotid artery, in particular at its terminal ending. Aneurysms in the posterior circulation are more common in children than adults. Children more often develop giant aneurysms, and may become symptomatic from the mass effect of the aneurysm (tumorlike symptoms). The more complex nature of pediatric aneurysms poses a larger challenge to treatment alongside with higher demands to the durability of treatment. Outcome and mortality are similar in children and adults, but long-term outcome in the pediatric population is influenced by the high rate of aneurysm recurrences and de novo formation of intracranial aneurysms. This urges the need for life-long follow-up and screening protocols. PMID:24696670

  12. [Hemodynamic adaptations in proximal cerebrovascular occlusion].

    PubMed

    De Ley, G

    1990-01-01

    In order to gain more insight into the pathophysiology of extracerebral cerebrovascular occlusion, the cerebral hemodynamic behaviour after uni- or bilateral carotid occlusion was investigated. In Wistar rats, acute occlusion of one common carotid artery leads to a moderate bilateral lowering of the resting hemispheric brain blood flow; no interhemispheric perfusion asymmetry is observed. During hypercapnia, however, a manyfold increase of the hemispheric blood flow is seen at the intact side, whereas blood flow increase at the side of the occlusion is suppressed indicating that the cerebrovascular reserve at the side of the occlusion is largely used to preserve resting hemispheric perfusion. During the days (1, 5, 15 and 30) following the occlusion, resting hemispheric blood flow is progressively restored rather rapidly (bilateral normalization on the fifth day) whereas restoration of the cerebrovascular reserve (hemispheric blood flow increase in hypercapnia) proceeds more slowly and a nearly normal hypercapnic response is reached on day thirty. Spontaneously Hypertensive Rats (SHR) show structural abnormalities of their blood vessels during the development of hypertension, leading to impaired adaptation possibilities of the cerebral vasculature after unilateral common carotid occlusion. This is indicated by the striking comparability of the compensation of hemispheric cerebral blood flow (in normo- and hypercapnia) of SH rats five days after unilateral carotid occlusion with the cerebral hemodynamic status of normotensive animals already seen 24 hours after the same occlusion. Consecutive bilateral common carotid occlusion shows that survival rate increases by increasing the interval between both occlusions. This survival relation is much more unfavorable in SH rats. The parallelism between the restoration of the measured CO2-reactivity of the blood flow in the involved hemisphere after unilateral carotid occlusion and the evolution of survival rate after

  13. Trigger factors for rupture of intracranial aneurysms in relation to patient and aneurysm characteristics.

    PubMed

    Vlak, Monique H M; Rinkel, Gabriel J E; Greebe, Paut; van der Bom, Johanna G; Algra, Ale

    2012-07-01

    Female gender, age above 60 years, and an aneurysm larger than 5 mm or location on the posterior circulation are associated with a higher rupture risk of intracranial aneurysms. We hypothesized that this association is explained by a higher susceptibility to (one of) the eight trigger factors that were recently identified. We included 250 patients with aneurysmal subarachnoid hemorrhage. We calculated relative risks (RR) with 95% confidence intervals (95% CI) of aneurysmal rupture for trigger factors according to sex, age, site, and size of the aneurysms by means of the case-crossover design. None of the triggers except for physical exercise differed according to patient and aneurysm characteristics. In the hour after exposure to physical exercise: (1) patients over the age of 60 have a six-times-higher risk of rupture (RR 13; 95% CI 6.3-26) than those of 60 years of age and under (RR 2.3; 1.3-4.1); (2) aneurysms at the internal carotid artery have a higher risk than those at other locations (RR 17; 7.8-37), but this was only statistically significant when compared to anterior communicating artery aneurysms (RR 3.2; 1.6-6.1); (3) aneurysms 5 mm or smaller had a higher risk of rupture (RR 9.5; 4.6-19) than larger aneurysms (RR 2.4; 1.3-4.3); and (4) women and men had similar risks. A higher susceptibility to exercise might explain part of the higher risk of rupture in older patients. Why women and patients with aneurysms larger than 5 mm or posterior circulation aneurysms have a higher risk of rupture remains to be settled.

  14. Update on aneurysm disease: current insights and controversies: peripheral aneurysms: when to intervene - is rupture really a danger?

    PubMed

    Dawson, Joe; Fitridge, Robert

    2013-01-01

    Peripheral artery aneurysms are rarer than abdominal aortic aneurysms (AAA), although the true prevalence is not well known. They often coexist with aortic and other peripheral artery aneurysms. In contrast to AAA, where the principal risk is that of rupture, thromboembolism is more common, contributing a bigger risk in the more common lesions. Although rupture does occur, with incidence related to anatomical site, aneurysm diameter cannot be used to guide management with the same confidence as in AAA. In addition, the rarity of these lesions results in a paucity of evidence with which to guide intervention. Consequently they are difficult lesions to manage, and numerous aneurysm and patient factors must be considered to provide treatment individualised for each case. We discuss popliteal, femoral, carotid, subclavian, upper limb, visceral and false aneurysms, focussing on the risk of rupture and thromboembolism, and current thresholds for intervention, based on the available published literature.

  15. [Evaluation of cerebro-vascular diseases with persistent carotid-basilar anastomosis].

    PubMed

    Harada, K; Uozumi, T; Kurisu, K; Sumida, M; Nakahara, A; Migita, K

    1994-12-01

    Five cases of cerebro-vascular diseases with carotid-basilar anastomosis were evaluated. Case 1: a 73-year-old female was diagnosed as having subarachnoid hemorrhage due to a ruptured aneurysm of the right internal carotid artery-posterior communicating artery bifurcation and demonstrated that a left proatlantal intersegmental artery. Case 2: a 38-year-old female showed intraventricle hemorrhage due to arteriovenous malformation and showed left primitive hypoglossal artery. Case 3: 73-year-old female was diagnosed as having subarachnoid hemorrhage due to a ruptured basilar top aneurysm and demonstrated that a right primitive hypoglossal artery. Case 4: a 29-year-old male with unruptured aneurysm of the left internal carotid artery-posterior communicating artery bifurcation, and right trigeminal artery was detected incidentally by magnetic resonance angiography (MRA). Furthermore, right proatlantal intersegmental artery was detected by conventional angiography. Case 5: a 76-year-old male was diagnosed as having subarachnoid hemorrhage due to a ruptured aneurysm of the anterior communicating artery. MRA showed the aneurysm and a primitive trigeminal artery. No clinical symptom related with carotid-basilar anastomosis was detected. Magnetic resonance angiography (MRA) was useful for diagnosis of asymptomatic carotid-basilar anastomosis. Especially, axial view of MRA by time of flight method detected two cases of a primitive trigeminal artery. And coronal view of MRA by phase contrast method is useful for diagnosis of primitive proatlantal intersegmental artery. More asymptomatic persistent carotid-basilar anastomosis may be detected by MRA.

  16. [A Case of Ruptured Peripheral Cerebral Aneurysm at Abnormal Vessels Associated with Middle Cerebral Artery Stenosis:Similarity to Moyamoya Disease].

    PubMed

    Miyazaki, Hajime; Kohno, Kanehisa; Tanaka, Hideo; Fukumoto, Shinya; Ichikawa, Haruhisa; Onoue, Shinji; Fumoto, Noriyuki; Ozaki, Saya; Maeda, Toshiharu

    2016-04-01

    We report a case of ruptured peripheral cerebral aneurysm at abnormal vessels associated with severe stenosis at the middle cerebral artery (MCA). A 66-year-old woman was admitted at our hospital with headache on foot. Computed tomography (CT) showed intracerebral hemorrhage in the left fronto-basal area. Three-dimensional-CT and conventional angiogram revealed abnormal vessels, which were similar to those seen in moyamoya disease, with a small enhancement close to the hematoma. On day 11, subsequent cerebral angiogram demonstrated an aneurysm at the peripheral portion of an abnormal vessel arising from the left A2. On day 17, soon after the diagnosis of the ruptured aneurysm was made (while still at the subacute stage), we operated on the aneurysm. Superficial temporal artery (STA)-MCA anastomosis was also performed to preserve cerebral blood flow and reduce hemodynamic stress. Several days after the operation, she had transient aphasia due to hyperperfusion of the MCA territory, but eventually recovered with no neurological deficit at discharge. Follow-up study revealed revascularization from the branches of the external carotid artery as well as the STA. On admission, we initially thought that this patient had abnormal vessels associated with arteriosclerotic MCA stenosis. However, the postoperative clinical course as well as the histopathological specimens of both the abnormal artery with the aneurysm and the STA revealed similar findings to those of moyamoya disease. Although this case did not satisfy the criteria for moyamoya disease, it is conceivable that a single arterial occlusive lesion associated with moyamoya-like vessels might develop in the same mechanism with that of moyamoya disease.

  17. Hybrid repair of penetrating aortic ulcer associated with right aortic arch and aberrant left innominate artery arising from aneurysmal Kommerell's diverticulum with simultaneous repair of bilateral common iliac artery aneurysms.

    PubMed

    Guo, Yuanyuan; Yang, Bin; Cai, Hongbo; Jin, Hui

    2014-02-01

    We present the first case of a hybrid endovascular approach to a penetrating aortic ulcer on the left descending aorta with a right aortic arch and aberrant left innominate artery arising from an aneurysmal Kommerell's diverticulum. The patient also had bilateral common iliac artery aneurysms. The three-step procedure consisted of a carotid-carotid bypass, followed by endovascular exclusion of the ulcer and the aneurysmal Kommerell's diverticulum, and then completion by covering the iliac aneurysms. The patient had no complications at 18 months after surgery. In such rare configurations, endovascular repair is a safe therapeutic option.

  18. Brain aneurysm repair

    MedlinePlus

    ... aneurysm repair; Dissecting aneurysm repair; Endovascular aneurysm repair - brain; Subarachnoid hemorrhage - aneurysm ... Your scalp, skull, and the coverings of the brain are opened. A metal clip is placed at ...

  19. Newtonian and non-Newtonian blood flow in coiled cerebral aneurysms.

    PubMed

    Morales, Hernán G; Larrabide, Ignacio; Geers, Arjan J; Aguilar, Martha L; Frangi, Alejandro F

    2013-09-03

    Endovascular coiling aims to isolate the aneurysm from blood circulation by altering hemodynamics inside the aneurysm and triggering blood coagulation. Computational fluid dynamics (CFD) techniques have the potential to predict the post-operative hemodynamics and to investigate the complex interaction between blood flow and coils. The purpose of this work is to study the influence of blood viscosity on hemodynamics in coiled aneurysms. Three image-based aneurysm models were used. Each case was virtually coiled with a packing density of around 30%. CFD simulations were performed in coiled and untreated aneurysm geometries using a Newtonian and a Non-Newtonian fluid models. Newtonian fluid slightly overestimates the intra-aneurysmal velocity inside the aneurysm before and after coiling. There were numerical differences between fluid models on velocity magnitudes in coiled simulations. Moreover, the non-Newtonian fluid model produces high viscosity (>0.007 [Pas]) at aneurysm fundus after coiling. Nonetheless, these local differences and high-viscous regions were not sufficient to alter the main flow patterns and velocity magnitudes before and after coiling. To evaluate the influence of coiling on intra-aneurysmal hemodynamics, the assumption of a Newtonian fluid can be used.

  20. Serpentine Cavernous Aneurysm Presented with Visual Symptoms Improved by Endovascular Coil Trapping

    PubMed Central

    Oh, Myeong-Jin; Shin, Dong-Seong; Se, Rady

    2016-01-01

    This report describes a case of a serpentine fusiform aneurysm of the internal carotid artery in a patient who presented with visual disturbances. The serpentine aneurysm was treated successfully by coil trapping and occlusion of the parent artery, accompanied by balloon dilation. Nine months post-operatively, the patient's visual acuity had improved considerably. PMID:28184349

  1. Multiple fusiform cerebral aneurysms – case report

    PubMed Central

    Jaworska, Katarzyna; Dołowy, Joanna; Kuśmierska, Małgorzata; Kuniej, Tomasz; Jaźwiec, Przemysław

    2012-01-01

    Summary Background: A true aneurysym is a dilation of arterial lumen as a consequence of congenital or acquired abnormalities leading to a reduction of mechanical resistance of vascular wall, most commonly caused by its defected structure in the form of absence or weakening of the muscular and/or elastic layer. From the pathophysiological point of view, cerebral aneurysms can be classified as ‘saccular’ – most commonly occurring, and ‘other types’, including fusiform/dolichoectatic, dissecting, serpentine, posttraumatic, mycotic and giant aneurysms with or without intra-aneurysmal thrombosis. Case Report: We present a rare case of a patient with multiple fusiform dilations of cerebral vessels and giant fusiform aneurysm in supraclinoid segment of the internal carotid artery. The patient presented to hospital because of sudden, severe vertigo with nausea, impaired balance and disturbed vision. Vascular anomalies were detected on CT scanning without contrast. The diagnostic work-up was complemented by CT angiography, MRI and cerebral angiography. Conclusions: Aneurysm located within the intracranial arteries is one of the most common vascular defects of the brain. The number, size and location of aneurysms are highly variable. Aneurysms can have either supra- or infratentorial location, affecting a single or multiple arteries within one or both brain hemispheres. There is often a correlation between the location of the aneurysm and its etiology, as in case of so-called mirror-image aneurysms. Symmetrically located aneurysms may indicate a defect in vascular structure. Asymmetric location, as in the patient described above, is more likely due to acquired causes, mainly atherosclerosis, but also septic emboli or blood disorders. PMID:22802866

  2. Carotid Ultrasound Imaging

    MedlinePlus

    ... Index A-Z Ultrasound - Carotid Carotid ultrasound uses sound waves to produce pictures of the carotid arteries ... pictures of the inside of the body using sound waves. Ultrasound imaging, also called ultrasound scanning or ...

  3. A Case of Large Anterior Paraclinoid Aneurysm with Intraoperative Premature Rupture

    PubMed Central

    Ichimura, Shinya; Inaba, Makoto; Kagami, Hiroshi

    2012-01-01

    We report here troubleshooting of intraoperative premature rupture with large anterior paraclinoid aneurysm, which was successfully clipped. A 61-year-old woman with left nasal hemianopia was referred to our institute. Preoperative three-dimensional computed tomography angiography and a left internal carotid artery angiogram showed a large left anterior clinoid aneurysm adjacent to the anterior clinoid process. Aneurysm was ruptured prematurely and tentative clipping of the dome of the aneurysm was done incidentally to stop bleeding and to reduce the volume of the aneurysm. The anterior clinoid process and superior wall of the orbit were drilled out safely, since the tentative clipping had created sufficient space between the aneurysm and the anterior clinoid process to perform the procedure. The proximal neck was observed and tandem clipping was applied to the aneurysm. Intraoperative and postoperative angiography revealed complete disappearance of the aneurysm. PMID:23946926

  4. A case of large anterior paraclinoid aneurysm with intraoperative premature rupture.

    PubMed

    Ichimura, Shinya; Inaba, Makoto; Kagami, Hiroshi

    2012-10-01

    We report here troubleshooting of intraoperative premature rupture with large anterior paraclinoid aneurysm, which was successfully clipped. A 61-year-old woman with left nasal hemianopia was referred to our institute. Preoperative three-dimensional computed tomography angiography and a left internal carotid artery angiogram showed a large left anterior clinoid aneurysm adjacent to the anterior clinoid process. Aneurysm was ruptured prematurely and tentative clipping of the dome of the aneurysm was done incidentally to stop bleeding and to reduce the volume of the aneurysm. The anterior clinoid process and superior wall of the orbit were drilled out safely, since the tentative clipping had created sufficient space between the aneurysm and the anterior clinoid process to perform the procedure. The proximal neck was observed and tandem clipping was applied to the aneurysm. Intraoperative and postoperative angiography revealed complete disappearance of the aneurysm.

  5. Treatment strategies for aneurysms associated with moyamoya disease.

    PubMed

    Zhang, Lei; Xu, Kan; Zhang, Yandong; Wang, Xin; Yu, Jinlu

    2015-01-01

    The treatment of aneurysms associated with moyamoya disease (MMD) is difficult for neurosurgeons, and little is known of strategy options. This report constitutes a comprehensive review of the literature. We summarize the known treatments and their clinical outcomes according to the site of the aneurysm: in major arteries, peripheral arteries, moyamoya vessels, meningeal arteries, or at the site of anastomosis. The literature review indicates that the treatment of MMD-associated aneurysms varies according to the site of the aneurysm and its hemodynamic characteristics. In particular, the treatment for basilar tip aneurysms remains challenging, since both endovascular embolization and direct clipping are difficult. The potential risk for ischemia should be considered in selecting endovascular or surgical approaches. Revascularization surgery, which is important for the treatment of MMD, also determines the clinical treatment outcome of aneurysms associated with MMD.

  6. Cervical artery tortuosity is associated with intracranial aneurysm.

    PubMed

    Labeyrie, Paul-Emile; Braud, Florent; Gakuba, Clément; Gaberel, Thomas; Orset, Cyrille; Goulay, Romain; Emery, Evelyne; Courthéoux, Patrick; Touzé, Emmanuel

    2017-01-01

    Background Intracranial aneurysms may be associated with an underlying arteriopathy, leading to arterial wall fragility. Arterial tortuosity is a major characteristic of some connective tissue disease. Aim To determine whether intracranial aneurysm is associated with an underlying arteriopathy. Methods Using a case-control design, from May 2012 to May 2013, we selected intracranial aneurysm cases and controls from consecutive patients who had conventional cerebral angiography in our center. Cases were patients with newly diagnosed intracranial aneurysm. Controls were patients who had diagnostic cerebral angiography and free of aneurysm. The prevalence of tortuosity, retrospectively assessed according to standard definitions, was compared between cases and controls and, association between tortuosity and some aneurysm characteristics was examined, in cases only. Results About 659 arteries from 233 patients (112 cases and 121 controls) were examined. Tortuosity was found in 57 (51%) cases and 31 (26%) controls (adjusted OR = 2.71; 95%CI, 1.53-4.80). The same trend was found when looking at each tortuosity subtype (simple tortuosity, coil, kink) or at carotid or vertebral territory separately. In contrast, no association between tortuosity and rupture status, aneurysm number or neck size was found. Conclusions Cervical artery tortuosity is significantly associated with intracranial aneurysm, although not related to main aneurysm characteristics. Our results support the presence of an underlying diffuse arteriopathy in intracranial aneurysm patients.

  7. Flow diversion for complex intracranial aneurysms in young children.

    PubMed

    Navarro, Ramon; Brown, Benjamin L; Beier, Alexandra; Ranalli, Nathan; Aldana, Philipp; Hanel, Ricardo A

    2015-03-01

    Pediatric intracranial aneurysms are exceedingly rare and account for less than 5% of all intracranial aneurysms. Open surgery to treat such aneurysms has been shown to be more durable than endovascular techniques, and durability of treatment is particularly important in the pediatric population. Over the past 2 decades, however, a marked shift in aneurysm treatment from open surgery toward endovascular procedures has occurred for adults. The authors describe their early experience in treating 3 unruptured pediatric brain aneurysms using the Pipeline embolization device (PED). The first patient, a girl with Majewski osteodysplastic primordial dwarfism Type II who was harboring multiple intracranial aneurysms, underwent two flow diversion procedures for a vertebrobasilar aneurysm and a supraclinoid internal carotid artery aneurysm. The second patient underwent PED placement on a previously coiled but enlarging posterior communicating artery aneurysm. All procedures were uneventful, with no postsurgical complications, and led to complete angiographic obliteration of the aneurysms. To the authors' knowledge, this is the first series of flow diversion procedures in children reported in the medical literature. While flow diversion is a new and relatively untested technology in children, outcomes in adults have been promising. For challenging lesions in the pediatric population, flow diversion may have a valuable role as a well-tolerated, safe treatment with durable results. Many issues remain to be addressed, such as the durability of flow diverters over a very long follow-up and vessel response to growth in the presence of an endoluminal device.

  8. Coexistence of intracranial epidermoid tumor and multiple cerebral aneurysms

    PubMed Central

    Yao, Pei-Sen; Lin, Zhang-Ya; Zheng, Shu-Fa; Lin, Yuan-Xiang; Yu, Liang-Hong; Jiang, Chang-Zhen; Kang, De-Zhi

    2017-01-01

    Abstract Rationale: There were a few case reports concerning epidermoid tumor coexisted with multiple cerebral aneurysms. Here, we present one case of coexistence of intracranial epidermoid tumor and multiple cerebral aneurysms and performed a literature review. Patient concerns: A 42 years old male patient was admitted to our institution with complaints of headache and dizziness. Interventions: The radiological examinations showed a hypointense lesion in the right parasellar and petrous apex region and an ipsilateral saccular aneurysm originated from the M2–M3 junction of the right middle cerebral artery (MCA) and a saccular aneurysm of the clinoid segment of right internal carotid artery (ICA). Interventions: The patients underwent a right frontotemporal approach for removal of the epidermoid tumor and clipping of the MCA aneurysm in one stage. The aneurysm located at the clinoid segment of ICA was invisible and untreated during operation. Outcomes: No postoperative complications were found in the patient. The patient's follow up after 5 years of surgical treatment was uneventful, and the untreated aneurysm remains stable. Lessons: The coexistence of intracranial epidermoid tumor and cerebral aneurysm is a rare event. The secondly inflammation in cerebral arterial wall may be responsible for the aneurysm formation. Surgical treatment of the intracranial epidermoid tumor and cerebral aneurysm repair may be an optimal scheme in one stage. PMID:28151901

  9. Mixed aneurysm: A new proposed nomenclature for a rare condition

    PubMed Central

    Crusius, Cassiano U.; de Aguiar, Paulo Henrique P.; Crusius, Marcelo U.

    2017-01-01

    Background: Mixed intracranial aneurysms are vascular lesions appearing in the ruptured saccular aneurysms whose blood is contained by perivascular tissues forming another cavity called pseudoaneurysm. All cases until now have been reported in the literature with subarachnoid hemorrhage. Case Description: A 65-year-old woman presented with multiple brain aneurysms with no history of subarachnoid hemorrhage. Endovascular treatment was chosen for left-sided aneurysms [lateral carotid wall (LCW) and posterior communicating (PCom)]. After the embolization of the LCW aneurysm, the patient developed a left third nerve palsy. A head computed tomography scan was immediately performed which did not show any SAH. The control angiography demonstrated PCom aneurysm with intraaneurysmal contrast retention even in the venous phase, along with modification of the aneurismal sac format, leading to diagnoses of mixed aneurysm. The PCom aneurysm was successfully coiled and an operation was performed to clip the right side aneurysms. The patient was discharged after 10 postoperative days. Conclusion: Mixed intracranial aneurysm has special radiological characteristics that should be promptly recognized to offer the best treatment. PMID:28303209

  10. [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.

  11. Embolization of experimental aneurysms using a heparin-loaded stent graft with micropores

    SciTech Connect

    Nishi, Shogo; Nakayama, Yasuhide; Ueda-Ishibashi, Hatsue; Matsuda, Takehisa

    2003-03-01

    Purpose: For percutaneous transluminal angioplasty (PTA), a heparin-loaded stent graft, composed of a commercially available metallic stent with a microporous and surface-modified thin film, has been developed. Early controlled endothelialization is promoted by a regular array of micropores produced by an excimer laser ablation technique. Early thrombus is prevented by a drug delivery system established by impregnation of photoreactive gelatin with heparin. Our stent grafts were used for embolization of experimental carotid aneurysms with an autologous external jugular vein patch in dogs. Materials and methods: At 1 month after formation, the aneurysms were occluded with stent grafts. Affected arteries were removed with the aneurysms, immediately (two aneurysms in one dog), 1 week (four aneurysms in two dogs), 1 month (three aneurysms in two dogs) and 3 months (four aneurysms in two dogs) after embolization, and were studied histologically to evaluate patency and endothelialization over the intraluminal surface of the thin film. Results: Treated carotid arteries were all patent with occluded aneurysms completely at any periods. Even at 1 week after embolization, endothelialization was confirmed on the surface of the stent graft on the lumen side. At 1 and 3 months, all treated aneurysms with enough patent parent arteries were filled with organized tissues and completely occluded. Conclusion: Our developed stent graft appears to be promising for the treatment of aneurysms, especially with respect to immediate termination of blood inflow and early endothelialization in the neck of the aneurysm.

  12. Stent-Assisted Endovascular Treatment of Anterior Communicating Artery Aneurysms – Literature Review

    PubMed Central

    Kocur, Damian; Ślusarczyk, Wojciech; Przybyłko, Nikodem; Bażowski, Piotr; Właszczuk, Adam; Kwiek, Stanisław

    2016-01-01

    Summary The anterior cerebral artery is a common location of intracranial aneurysms. The standard coil embolization technique is limited by its inability to occlude wide-neck aneurysms. Stent deployment across the aneurysm neck supports the coil mass inside the aneurysmal sac, and furthermore, has an effect on local hemodynamic and biologic changes. In this article, various management strategies and techniques as well as angiographic outcomes and complications related to stent-assisted endovascular treatment of anterior communicating artery aneurysms are presented. This treatment method is safe and associated with low morbidity and mortality rates. PMID:27559426

  13. Treatment of Basilar Aneurysms with SMP Foams

    NASA Astrophysics Data System (ADS)

    Ortega, J. M.; Rodriguez, J. N.; Maitland, D. J.; Wilson, T. S.; Hartman, J.

    2006-11-01

    Researchers in the Medical Division at LLNL are currently developing a shape memory polymer (SMP) foam aneurysm treatment technique. This technique involves the catheter delivery of a compressed piece of SMP foam to an aneurysm. When the foam is heated by laser radiation from a diffusing fiber-optic element embedded within the catheter, the foam expands, filling the aneurysm volume. If proven successful, such a treatment alternative will provide clinicians the ability to not only isolate an aneurysm from the vascular system with one device, but also to customize the shape of the lumen beneath the aneurysm neck. Consequently, the flow patterns beneath the aneurysm neck could potentially be optimized to minimize the hemodynamic stresses on the lumen. In this computational study, multiple lumen shapes are simulated beneath the necks of several patient-specific basilar aneurysms. A comparison is made between the pre-treatment and post-treatment configurations, as well as with a conventional surgical clipping configuration. This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48. UCRL-ABS-222933.

  14. [Recurrence of a giant fusiform aneurysm after neck clipping: case report].

    PubMed

    Iwamuro, Y; Miyake, H; Ito, T; Kumai, J; Kuroda, T; Sugino, T

    1996-04-01

    The patient was a 71-year-old female. On December 20, 1995, she suddenly developed a severe headache with vomiting and was transferred to our hospital. On admission, her conciousness level was 1-2 on the Japan Coma Scale, but there was no neurological deficit except for right oculomotor palsy. Computed tomography showed subarachnoid hemorrhage which had permeated the right lateral ventricle. On cerebral angiography, a giant fusiform aneurysm in the right internal carotid artery was recognized. During the emergency operation, neither neck clipping nor carotid reconstruction was possible because of the tight adhesion of the aneurysm to the peripheral tissue. On account of this, proximal clipping of the carotid artery with external carotid-middle cerebral artery anastomosis with saphenous vein graft was selected. This patient had had an episode of subarachnoid hemorrhage owing to rupture of the right internal carotid-posterior communicating artery aneurysm ten years earlier. At that time, the aneurysmal neck was clipped with a slight residual neck and she left the hospital on foot. Five days later, when the aneurysm was found to be completely thrombosed on CT scan, antiplatelet therapy was started. Although low density areas which corresponded to the regions fed by the right anterior choroidal artery were presented, re-rupture did not occur. Follow-up angiography showed that the aneurysm was completely thrombosed and that the right middle cerebral and the anterior cerebral artery blood was circulated via the vein graft. Among recurrent cases of aneurysm after neck clipping, it is unusual for a giant fusiform aneurysm to be recognized. The growth may have been caused by sclerotic change of the arterial wall. Oculomotor palsy may have delayed the detection of the recurrence of the aneurysm. When residual neck is presented on follow-up angiography, the next angiography should be carried out within at least three years. In this case, antiplatelet therapy was effective to

  15. Carotid artery stenting versus carotid endarterectomy.

    PubMed

    Nanna, Michael G; Gomes, Paulina; Njoh, Roland F; Ward, Charisse; Attaran, Robert R; Mena, Carlos

    2016-09-01

    Stroke remains a significant contributor to morbidity and mortality in developed countries. Carotid artery stenosis is a major cause of stroke. Advances in medical therapy, surgical technique and endovascular maturation has resulted in options for the treatment of carotid stenosis. Here, we present a review of carotid artery stenting and carotid endarterectomy as it applies to trials comparing and contrasting the two treatment options. We also explore the intricacies surrounding reimbursement of these treatment strategies in the USA.

  16. Computational analysis of anterior communicating artery aneurysm shear stress before and after aneurysm formation

    NASA Astrophysics Data System (ADS)

    Castro, Marcelo A.; Putman, Christopher M.; Cebral, Juan R.

    2011-12-01

    It is widely accepted that complexity in the flow pattern at the anterior communicating artery (AComA) is associated with the high rate of aneurysm formation at that location observed in large studies. The purpose of this work is to study associations between hemodynamic patterns, and AComA aneurysm initiation by comparing hemodynamics in the aneurysm and the normal model where the aneurysm was computationally removed. Vascular models of both right and left circulation were independently reconstructed from three-dimensional rotational angiography images using deformable models after image registration of both images, and fused using a surface merging algorithm. The geometric models were then used to generate high-quality volumetric finite element grids of tetrahedra with an advancing front technique. For each patient, the second anatomical model was created by digitally removing the aneurysm. It was iteratively achieved by applying a Laplacian smoothing filter and remeshing the surface. Finite element blood flow numerical simulations were performed for both the pathological and normal models under the same personalized pulsatile flow conditions imposed at the inlets of both models. The Navier-Stokes equations were numerically integrated by using a finite-element formulation. It was observed that aneurysms initiated in regions of high and moderate WSS in the counterpart normal models. Adjacent or close to those regions, low WSS portions of the arterial wall were not affected by the disease. These results are in line with previous observations at other vascular locations.

  17. Combined Visualization of Wall Thickness and Wall Shear Stress for the Evaluation of Aneurysms.

    PubMed

    Glaßer, Sylvia; Lawonn, Kai; Hoffmann, Thomas; Skalej, Martin; Preim, Bernhard

    2014-12-01

    For an individual rupture risk assessment of aneurysms, the aneurysm's wall morphology and hemodynamics provide valuable information. Hemodynamic information is usually extracted via computational fluid dynamic (CFD) simulation on a previously extracted 3D aneurysm surface mesh or directly measured with 4D phase-contrast magnetic resonance imaging. In contrast, a noninvasive imaging technique that depicts the aneurysm wall in vivo is still not available. Our approach comprises an experiment, where intravascular ultrasound (IVUS) is employed to probe a dissected saccular aneurysm phantom, which we modeled from a porcine kidney artery. Then, we extracted a 3D surface mesh to gain the vessel wall thickness and hemodynamic information from a CFD simulation. Building on this, we developed a framework that depicts the inner and outer aneurysm wall with dedicated information about local thickness via distance ribbons. For both walls, a shading is adapted such that the inner wall as well as its distance to the outer wall is always perceivable. The exploration of the wall is further improved by combining it with hemodynamic information from the CFD simulation. Hence, the visual analysis comprises a brushing and linking concept for individual highlighting of pathologic areas. Also, a surface clustering is integrated to provide an automatic division of different aneurysm parts combined with a risk score depending on wall thickness and hemodynamic information. In general, our approach can be employed for vessel visualization purposes where an inner and outer wall has to be adequately represented.

  18. Pressure Drop in Tortuosity/Kinking of the Internal Carotid Artery: Simulation and Clinical Investigation

    PubMed Central

    Wang, Lijun; Zhao, Feng; Wang, Daming; Hu, Shen; Liu, Jiachun; Zhou, Zhilun; Lu, Jun; Qi, Peng; Song, Shiying

    2016-01-01

    Background. Whether carotid tortuosity/kinking of the internal carotid artery leads to cerebral ischemia remains unclear. There is very little research about the hemodynamic variation induced by carotid tortuosity/kinking in the literature. The objective of this study was to research the blood pressure changes induced by carotid tortuosity/kinking. Methods. We first created a geometric model of carotid tortuosity/kinking. Based on hemodynamic boundary conditions, the hemodynamics of carotid tortuosity and kinking were studied via a finite element simulation. Then, an in vitro system was built to validate the numerical simulation results. The mean arterial pressure changes before and after carotid kinking were measured using pressure sensors in 12 patients with carotid kinking. Results. Numerical simulation revealed that the pressure drops increased with increases in the kinking angles. Clinical tests and in vitro experiments confirmed the numerical simulation results. Conclusions. Carotid kinking leads to blood pressure reduction. In certain conditions, kinking may affect the cerebral blood supply and be associated with cerebral ischemia. PMID:27195283

  19. Carotid artery anatomy (image)

    MedlinePlus

    There are four carotid arteries, two on each side of the neck: right and left internal carotid arteries, and right and left external carotid arteries. The carotid arteries deliver oxygen-rich blood from the heart to the head and brain.

  20. Flow patterns and shear stress waveforms in intracranial aneurysms: The effect of pulsatility

    NASA Astrophysics Data System (ADS)

    Sotiropoulos, Fotis; Le, Trung; Borazjani, Iman

    2009-11-01

    The wall shear stress on the dome of intracranial aneurysms has been hypothesized to be an important factor in aneurysm pathology and depends strongly on the hemodynamics inside the dome. The importance of patient-specific geometry on the hemodynamics of aneurysms has long been established but the significance of patient-specific inflow waveform is largely unexplored. In this work we seek to systematically investigate and quantify the effects of inflow waveform on aneurysm hemodynamics. We carry out high resolution numerical simulations for an anatomic intracranial aneurysm obtained from 3D rotational angiography (3DRA) data for various inflow waveforms. We show that both the vortex formation process and wall-shear stress dynamics on the aneurysm dome depend strongly on the characteristics of the inflow waveform. We also present preliminary evidence suggesting that a simple non-dimensional number (named the Aneurysm number), incorporating both geometry and inflow waveform effects, could be a good qualitative predictor of the general hemodynamic patterns that will arise in a given aneurysm geometry for a particular waveform.

  1. Pseudoaneurysm of the Common Carotid Artery in an Infant due to Swallowed Fish Bone

    PubMed Central

    Jean Roger, Moulion Tapouh; Marcus, Fokou; Emmanuel, Fongang; Boniface, Moifo; Alain Georges, Juimo

    2015-01-01

    Carotid artery pseudoaneurysm is a rare condition, particularly in the paediatric population. Only about 30 cases of carotid artery aneurysms in infants have been published until now. This paper reports the case of a giant pseudoaneurysm of the left common carotid artery due to swallowed fish bone by an 8-year-old boy. This pseudoaneurysm was 5.5 cm transverse-diameter and resulted in severe respiratory distress. It was treated by resection and end-to-end anastomosis with satisfactory outcome after one-year follow-up. To the best of our knowledge, this is the largest carotid artery pseudoaneurysm ever described in children. PMID:26783485

  2. Selective delayed management of blunt traumatic left common carotid artery injury using hypothermic circulatory arrest.

    PubMed

    Nakamura, Kunihide; Onitsuka, Toshio; Yano, Mitsuhiro; Yano, Yoshikazu; Saitoh, Tomokazu; Niina, Katsuhiko

    2005-05-01

    Most traumatic carotid artery aneurysms occur at or close to its bifurcation, and traumatic aneurysm of the intrathoracic carotid arteries are rare. We describe a case of false aneurysm at the origin of the left common carotid artery (LCCA) after blunt trauma. A 53-year-old man suffered a blow from a broken steel plate, which flew from a working concrete crusher over his neck when he looked down the machine. Chest computed tomography revealed aneurysm of the LCCA, and aortic arch arteriography demonstrated a false aneurysm of about 3 x 5 cm at the origin of the LCCA, with loss of arterial continuity and abnormal tortuosity above the aneurysm. An ascending aorta to LCCA bypass graft was placed during the cooling period of cardiopulmonary bypass, and mattress sutures were placed in the normal aorta to close the origin of the LCCA under hypothermic circulatory arrest because of the extreme danger of dissection. The LCCA was transected partially at its origin from the aorta. We speculated that the direct lifting force which caused the carotid artery to move upward might produce a tear at the junction of the LCCA and the aortic arch.

  3. Wall shear stress at the initiation site of cerebral aneurysms.

    PubMed

    Geers, A J; Morales, H G; Larrabide, I; Butakoff, C; Bijlenga, P; Frangi, A F

    2017-02-01

    Hemodynamics are believed to play an important role in the initiation of cerebral aneurysms. In particular, studies have focused on wall shear stress (WSS), which is a key regulator of vascular biology and pathology. In line with the observation that aneurysms predominantly occur at regions of high WSS, such as bifurcation apices or outer walls of vascular bends, correlations have been found between the aneurysm initiation site and high WSS. The aim of our study was to analyze the WSS field at an aneurysm initiation site that was neither a bifurcation apex nor the outer wall of a vascular bend. Ten cases with aneurysms on the A1 segment of the anterior cerebral artery were analyzed and compared with ten controls. Aneurysms were virtually removed from the vascular models of the cases to mimic the pre-aneurysm geometry. Computational fluid dynamics (CFD) simulations were created to assess the magnitude, gradient, multidirectionality, and pulsatility of the WSS. To aid the inter-subject comparison of hemodynamic variables, we mapped the branch surfaces onto a two-dimensional parametric space. This approach made it possible to view the whole branch at once for qualitative evaluation. It also allowed us to empirically define a patch for quantitative analysis, which was consistent among subjects and encapsulated the aneurysm initiation sites in our dataset. To test the sensitivity of our results, CFD simulations were repeated with a second independent observer virtually removing the aneurysms and with a 20 % higher flow rate at the inlet. We found that branches harboring aneurysms were characterized by high WSS and high WSS gradients. Among all assessed variables, the aneurysm initiation site most consistently coincided with peaks of temporal variation in the WSS magnitude.

  4. Integrating the theories of Darwin and Bernoulli: maladaptive baroreceptor network dysfunction may explain the pathogenesis of aortic aneurysms.

    PubMed

    Conley, Buford R; Doux, John D; Lee, Patrick Y; Bazar, Kimberly A; Daniel, Stephanie M; Yun, Anthony J

    2005-01-01

    Current treatment options for aortic aneurysms are suboptimal and their pathogenic mechanisms remain unclear. We propose the existence of a coordinated multi-node baroreceptor network that measures pressures at all vascular bifurcations and enables system-wide hemodynamic coordination and vasomotor regulation, in accordance with the principle of Bernoulli. While the presence of baroreceptors at bifurcations remains unknown, behavior at the level of systems predicts their existence, possibly as glomus cell derivatives. We propose that pressure misregistration among sensor nodes at different vascular bifurcations can precipitate feed-forward dysfunctions that promote thrombosis, inflammation, and vasomotor dysregulation resulting in aneurysm formation. One example of this phenomenon is aortic aneurysm, which is currently attributed to focal anatomic defects. As plaque builds in the infrarenal aorta, the increased blood velocity through this segment can widen the difference between pressures sensed at the iliac and the renal artery bifurcations. Due to the Bernoulli effect, this change creates an incorrect impression of reduced dynamic pressure at the kidneys. The erroneous perception of hypovolemia can induce a pernicious cycle of maladaptive adrenergia and associated coagulation and thrombosis, particularly in the infrarenal aortic segment as the body attempts to normalize renal perfusion. Atherosclerosis can further exacerbate baroreceptor dysfunction by interfering with sensor biology in feed-forward fashion. Hypertension may be a consequence as well as a source of atherosclerosis and aneurysm. The described system may have evolved when trauma-related hypovolemia was a far more prevalent driver of natural selection but may be rendered maladaptive in the setting of modern stressors. Failure to address these factors may explain the suboptimal long-term outcomes with current surgical and endovascular treatments for aneurysms. Implications for other potential sensor

  5. The effect of flow recirculation on abdominal aortic aneurysm

    NASA Astrophysics Data System (ADS)

    Taib, Ishkrizat; Amirnordin, Shahrin Hisham; Madon, Rais Hanizam; Mustafa, Norrizal; Osman, Kahar

    2012-06-01

    The presences of flow recirculation at the abdominal aortic aneurysm (AAA) region yield the unpredictable failure of aneurismal wall. The failure of the aneurismal wall is closely related to the hemodynamic factor. Hemodynamic factor such as pressure and velocity distribution play a significance role of aneurysm growth and rupture. By using the computational approach, the influence of hemodynamic factor is investigated using computational fluid dynamic (CFD) method on the virtual AAA model. The virtual 3D AAAs model was reconstructed from Spiral Computed Tomography scan (CT-scan). The blood flow is assumed as being transient, laminar and Newtonian within a rigid section of the vessel. The blood flow also driven by an imposed of pressure gradient in the form of physiological waveform. The pulsating blood flow is also considered in this simulation. The results on pressure distribution and velocity profile are analyzed to interpret the behaviour of flow recirculation. The results show the forming of vortices is seen at the aneurysm bulge. This vortices is form at the aneurysm region then destroyed rapidly by flow recirculation. Flow recirculation is point out much higher at distal end of aneurysm closed to iliac bifurcation. This phenomenon is managed to increase the possibility of aneurysm growth and rupture.

  6. A New Murine Model of Endovascular Aortic Aneurysm Repair

    PubMed Central

    Rouer, Martin; Meilhac, Olivier; Delbosc, Sandrine; Louedec, Liliane; Pavon-Djavid, Graciela; Cross, Jane; Legagneux, Josette; Bouilliant-Linet, Maxime; Michel, Jean-Baptiste; Alsac, Jean-Marc

    2013-01-01

    Endovascular aneurysm exclusion is a validated technique to prevent aneurysm rupture. Long-term results highlight technique limitations and new aspects of Abdominal aortic aneurysm (AAA) pathophysiology. There is no abdominal aortic aneurysm endograft exclusion model cheap and reproducible, which would allow deep investigations of AAA before and after treatment. We hereby describe how to induce, and then to exclude with a covered coronary stentgraft an abdominal aortic aneurysm in a rat. The well known elastase induced AAA model was first reported in 19901 in a rat, then described in mice2. Elastin degradation leads to dilation of the aorta with inflammatory infiltration of the abdominal wall and intra luminal thrombus, matching with human AAA. Endovascular exclusion with small covered stentgraft is then performed, excluding any interactions between circulating blood and the aneurysm thrombus. Appropriate exclusion and stentgraft patency is confirmed before euthanasia by an angiography thought the left carotid artery. Partial control of elastase diffusion makes aneurysm shape different for each animal. It is difficult to create an aneurysm, which will allow an appropriate length of aorta below the aneurysm for an easy stentgraft introduction, and with adequate proximal and distal neck to prevent endoleaks. Lots of failure can result to stentgraft introduction which sometimes lead to aorta tear with pain and troubles to stitch it, and endothelial damage with post op aorta thrombosis. Giving aspirin to rats before stentgraft implantation decreases failure rate without major hemorrhage. Clamping time activates neutrophils, endothelium and platelets, and may interfere with biological analysis. PMID:23851958

  7. Single-stage endovascular treatment in patients with severe extracranial large vessel stenosis and concomitant ipsilateral unruptured intracranial aneurysm

    PubMed Central

    Kaçar, Emre; Nas, Ömer Fatih; Erdoğan, Cüneyt; Hakyemez, Bahattin

    2015-01-01

    PURPOSE We aimed to evaluate the safety and effectiveness of single-stage endovascular treatment in patients with severe extracranial large vessel stenosis and concomitant ipsilateral unruptured intracranial aneurysm. METHODS Hospital database was screened for patients who underwent single-stage endovascular treatment between February 2008 and June 2013 and seven patients were identified. The procedures included unilateral carotid artery stenting (CAS) (n=4), bilateral CAS (n=2), and proximal left subclavian artery stenting (n=1) along with ipsilateral intracranial aneurysm treatment (n=7). The mean internal carotid artery stenosis was 81.6% (range, 70%–95%), and the subclavian artery stenosis was 90%. All aneurysms were unruptured. The mean aneurysm diameter was 7.7 mm (range, 5–13 mm). The aneurysms were ipsilateral to the internal carotid artery stenosis (internal carotid artery aneurysm) in five patients, and in the anterior communicating artery in one patient. The patient with subclavian artery stenosis had a fenestration aneurysm in the proximal basilar artery. Stenting of the extracranial large vessel stenosis was performed before aneurysm treatment in all patients. In two patients who underwent bilateral CAS, the contralateral carotid artery stenosis, which had no aneurysm distally, was treated initially. RESULTS There were no procedure-related complications or technical failure. The mean clinical follow-up period was 18 months (range, 9–34 months). One patient who underwent unilateral CAS experienced contralateral transient ischemic attack during the clinical follow-up. There was no restenosis on six-month follow-up angiograms, and all aneurysms were adequately occluded. CONCLUSION A single-stage procedure appears to be feasible for treatment of patients with severe extracranial large vessel stenosis and concomitant ipsilateral intracranial aneurysm. PMID:26359875

  8. A Parallel Lattice Boltzmann Model of a Carotid Artery

    NASA Astrophysics Data System (ADS)

    Boyd, J.; Ryan, S. J.; Buick, J. M.

    2008-11-01

    A parallel implementation of the lattice Boltzmann model is considered for a three dimensional model of the carotid artery. The computational method and its parallel implementation are described. The performance of the parallel implementation on a Beowulf cluster is presented, as are preliminary hemodynamic results.

  9. Case Report: A Troublesome Ophthalmic Artery Aneurysm

    PubMed Central

    Meling, T. R.; Sorteberg, W.; Bakke, S. J.; Jacobsen, E. A.; Lane, P.; Vajkoczy, P.

    2014-01-01

    Objective and Importance When treating large unruptured ophthalmic artery (OA) aneurysms causing progressive blindness, surgical clipping is still the preferred method because aneurysm sac decompression may relieve optic nerve compression. However, endovascular treatment of OA aneurysms has made important progress with the introduction of stents. Although this development is welcomed, it also makes the choice of treatment strategy less straightforward than in the past, with the potential of missteps. Clinical Presentation A 56-year-old woman presented with a long history of progressive unilateral visual loss and magnetic resonance imaging showing a 20-mm left-sided OA aneurysm. Intervention Because of her long history of very poor visual acuity, we considered her left eye to be irredeemable and opted for endovascular therapy. The OA aneurysms was treated with stent and coils but continued to grow, threatening the contralateral eye. Because she failed internal carotid artery (ICA) balloon test occlusion, we performed a high-flow extracranial-intracranial bypass with proximal ICA occlusion in the neck. However, aneurysm growth continued due to persistent circulation through reversed blood flow in distal ICA down to the OA and the cavernous portion of the ICA. Due to progressive loss of her right eye vision, we surgically occluded the ICA proximal to the posterior communicating artery and excised the coiled, now giant, OA aneurysm. This improved her right eye vision, but her left eye was permanently blind. Conclusion This case report illustrates complications of the endovascular and surgical treatment of a large unruptured OA aneurysm. PMID:25485220

  10. Aneurysm growth and de novo aneurysms during aneurysm surveillance.

    PubMed

    Serrone, Joseph C; Tackla, Ryan D; Gozal, Yair M; Hanseman, Dennis J; Gogela, Steven L; Vuong, Shawn M; Kosty, Jennifer A; Steiner, Calen A; Krueger, Bryan M; Grossman, Aaron W; Ringer, Andrew J

    2016-12-01

    OBJECTIVE Many low-risk unruptured intracranial aneurysms (UIAs) are followed for growth with surveillance imaging. Growth of UIAs likely increases the risk of rupture. The incidence and risk factors of UIA growth or de novo aneurysm formation require further research. The authors retrospectively identify risk factors and annual risk for UIA growth or de novo aneurysm formation in an aneurysm surveillance protocol. METHODS Over an 11.5-year period, the authors recommended surveillance imaging to 192 patients with 234 UIAs. The incidence of UIA growth and de novo aneurysm formation was assessed. With logistic regression, risk factors for UIA growth or de novo aneurysm formation and patient compliance with the surveillance protocol was assessed. RESULTS During 621 patient-years of follow-up, the incidence of aneurysm growth or de novo aneurysm formation was 5.0%/patient-year. At the 6-month examination, 5.2% of patients had aneurysm growth and 4.3% of aneurysms had grown. Four de novo aneurysms formed (0.64%/patient-year). Over 793 aneurysm-years of follow-up, the annual risk of aneurysm growth was 3.7%. Only initial aneurysm size predicted aneurysm growth (UIA < 5 mm = 1.6% vs UIA ≥ 5 mm = 8.7%, p = 0.002). Patients with growing UIAs were more likely to also have de novo aneurysms (p = 0.01). Patient compliance with this protocol was 65%, with younger age predictive of better compliance (p = 0.01). CONCLUSIONS Observation of low-risk UIAs with surveillance imaging can be implemented safely with good adherence. Aneurysm size is the only predictor of future growth. More frequent (semiannual) surveillance imaging for newly diagnosed UIAs and UIAs ≥ 5 mm is warranted.

  11. Assessment of Influences of Stenoses in Right Carotid Artery on Left Carotid Artery Using Wall Stress Marker

    PubMed Central

    Ghagare, Dushali; Chattopadhyay, Himadri

    2017-01-01

    Purpose. Atherosclerosis is a diseased condition of blood vessel. It causes partial blockage in lumen of vessel and affects hemodynamic of localized flowing blood. Complex geometries like region of bifurcation also affects hemodynamic to a larger extent. Complexity further increases in presence of stenoses at region of bifurcation. Such morphological change in vessel largely affects parent as well as corresponding sister and daughter vessels. In this paper, complexity in hemodynamic of blood in pair of carotid arteries (left and right carotid arteries) is evaluated in presence of stenoses at basilar segment of right artery in three-dimensional domain using reconstructed tomographic images of patient. Methods. Transient information of blood flow is obtained using four-dimensional phase-contrast MRI technique. Haematocrit component of blood at diseased condition is considered using Power Law and Quemada model. Numerical techniques are used to solve pressure-coupled governing equations of flowing blood. Results. Dysfunctions of endothelial cells near the wall are characterised by evaluating shear stress markers. Wall shear stress and its gradient based and harmonic based descriptors are calculated over complete geometry during one cardiac cycle. Conclusion. Internal branch of left carotid artery and external branch of right carotid artery are found prone to secondary stenoses in presence of primary stenoses at basilar segment of right carotid artery. PMID:28191460

  12. Common Carotid Artery Stump Syndrome Due to Mobile Thrombus Detected by Carotid Duplex Ultrasonography.

    PubMed

    Omoto, Shusaku; Hasegawa, Yuki; Sakai, Kenichiro; Matsuno, Hiromasa; Arai, Ayumi; Terasawa, Yuka; Mitsumura, Hidetaka; Iguchi, Yasuyuki

    2016-10-01

    Carotid stump syndrome is a cause of recurrent embolic stroke following occlusion of the ipsilateral internal carotid artery. The present report describes a case of recurrent cerebral embolism ipsilateral to a chronically occluded left common carotid artery (CCA), i.e., "CCA stump syndrome." Doppler color flow imaging showed anterograde flow in the left internal and external carotid arteries, which were supplied by collateral flow from the superior thyroid artery inflowing just proximal to the left carotid bifurcation. According to carotid duplex ultrasonography (CDU), a low-echoic mobile thrombus was noted at the distal stump of the occluded CCA, which presumably caused distal embolism. The low-echoic mobile thrombus dramatically changed to a homogenously high-echoic thrombus, and there was no recurrence of stroke after antiplatelet and anticoagulant therapy. This is the first report to demonstrate a CDU-verified temporal change in the thrombus at the stump in CCA stump syndrome. CDU is a noninvasive and useful technique to characterize hemodynamics, thrombus morphology, and the response to therapy.

  13. Brain aneurysm repair - discharge

    MedlinePlus

    ... gov/pubmed/22556195 . Szeder V, Tateshima S, Duckwiler GR. Intracranial aneurysms and subarachnoid hemorrhage. In: Daroff RB, Jankovic J, ... chap 67. Read More Aneurysm in the brain Brain aneurysm repair Brain surgery Recovering after stroke Seizures Smoking - ...

  14. Thoracic aortic aneurysm

    MedlinePlus

    ... common cause of a thoracic aortic aneurysm is hardening of the arteries . This condition is more common ... aortic aneurysm repair - open Aortic aneurysm repair - endovascular Hardening of the arteries High blood pressure Marfan syndrome ...

  15. Stent-Assisted Coil Embolization of a Wide-Neck Aneurysm of a Persistent Primitive Hypoglossal Artery

    SciTech Connect

    Baldi, Sebastian Zander, Tobias; Rabellino, Martin; Maynar, Manuel

    2009-03-15

    Persistent primitive hypoglossal artery (PPHA) represents the second most common carotid-vertebrobasilar anastomosis. The association of PPHA with intracranial aneurysms is not unusual. Treatment of aneurysms located on the PPHA itself is challenging due to the increased risk of ischemic complications secondary to the hypoglossal artery often being the sole contributor of flow to the posterior circulation. We report a case of a wide-neck aneurysm in a PPHA successfully treated using a stent-assisted coil embolization technique.

  16. Sac Angiography and Glue Embolization in Emergency Endovascular Aneurysm Repair for Ruptured Abdominal Aortic Aneurysm

    SciTech Connect

    Koike, Yuya Nishimura, Jun-ichi Hase, Soichiro Yamasaki, Motoshige

    2015-04-15

    PurposeThe purpose of this study was to demonstrate a sac angiography technique and evaluate the feasibility of N-butyl cyanoacrylate (NBCA) embolization of the ruptured abdominal aortic aneurysm (AAA) sac in emergency endovascular aneurysm repair (EVAR) in hemodynamically unstable patients.MethodsA retrospective case series of three patients in whom sac angiography was performed during emergency EVAR for ruptured AAA was reviewed. After stent graft deployment, angiography within the sac of aneurysm (sac angiography) was performed by manually injecting 10 ml of contrast material through a catheter to identify the presence and site of active bleeding. In two patients, sac angiography revealed active extravasation of the contrast material, and NBCA embolization with a coaxial catheter system was performed to achieve prompt sealing.ResultsSac angiography was successful in all three patients. In the two patients who underwent NBCA embolization for aneurysm sac bleeding, follow-up computed tomography (CT) images demonstrated the accumulation of NBCA consistent with the bleeding site in preprocedural CT images.ConclusionsEVAR is associated with a potential risk of ongoing bleeding from type II or IV endoleaks into the disrupted aneurysm sac in patients with severe coagulopathy. Therefore, sac angiography and NBCA embolization during emergency EVAR may represent a possible technical improvement in the treatment of ruptured AAA in hemodynamically unstable patients.

  17. [Asymptomatic carotid stenosis at high risk of ipsilateral cerebro-vascular events].

    PubMed

    Becker, F; Loppinet, A

    2004-01-01

    The management of asymptomatic carotid stenosis remains unclear in terms of screening as well as of treatment. The degree of carotid stenosis is not enough to clarify the debate. It seems useful to search among severe carotid stenosis parameters indicating higher ipsilateral stroke risk. Duplex ultrasound and transcranial Doppler offer this opportunity with a diagnostic battery allowing to evaluate hemodynamical risk (degree of stenosis, common carotid flow, MCA signal, cerebral vasoreactivity), thrombo-embolic risk (echostructure of the stenosis, micro-embolic signals, HITS) and progression of the stenosis.

  18. Congenital Absence of the Internal Carotid Artery

    SciTech Connect

    Florio, Francesco; Balzano, Silverio; Nardella, Michele; Strizzi, Vincenzo; Cammisa, Mario; Bozzini, Vincenzo; Catapano, Giuseppe; D'Angelo, Vincenzo

    1999-01-15

    We report three cases of congenital absence of an internal carotid artery (ICA), diagnosed incidentally by digital subtraction angiography. The analysis of the cases is based on the classification of segmental ICA agenesis proposed by Lasjaunias and Berenstein. Usually the patients with this rare vascular anomaly are asymptomatic; some may have symptoms related to cerebrovascular insufficiency, compression by enlarged intracranial collateral vessels, or complications associated with cerebral aneurysms. Diagnosis of congenital absence of ICA is made by skull base computed tomography (CT) scan, CT and magnetic resonance angiography, and conventional or digital subtraction angiography.

  19. Pipeline embolization device as primary treatment for cervical internal carotid artery pseudoaneurysms

    PubMed Central

    Wang, Arthur; Santarelli, Justin; Stiefel, Michael F.

    2017-01-01

    Background: Limited data exists on the durability and occlusion rate of treating extracranial cervical internal carotid artery pseudoaneurysms using the pipeline embolization device (PED) flow-diverting stent. Methods: Three patients presenting with dissecting cervical internal carotid artery pseudoaneurysms were treated with the PED as the sole treatment modality. Results: In all three patients, successful aneurysmal occlusion and parent vessel reconstruction occurred on immediate angiography and continued on 6-month follow-up. No immediate or delayed complications were seen, and all patients remained neurologically intact. Conclusion: Complete aneurysmal occlusion and long-term angiographic occlusion can occur after PED treatment of cervical carotid pseudoaneurysms. In select patients, the PED can be a suitable primary treatment modality with good neurological outcome for cervical carotid pseudoaneurysms. PMID:28217382

  20. Carotid Artery Disease

    MedlinePlus

    ... brain with blood. If you have carotid artery disease, the arteries become narrow, usually because of atherosclerosis. ... one of the causes of stroke. Carotid artery disease often does not cause symptoms, but there are ...

  1. Carotid artery surgery - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100124.htm Carotid artery surgery - series—Normal anatomy To use the sharing ... out of 4 Overview There are four carotid arteries, with a pair located on each side of ...

  2. Harvey W. Cushing and cerebrovascular surgery: Part I, Aneurysms.

    PubMed

    Cohen-Gadol, Aaron A; Spencer, Dennis D

    2004-09-01

    The development of surgical techniques for the treatment of intracranial aneurysms has paralleled the evolution of the specialty of neurological surgery. During the Cushing era, intracranial aneurysms were considered inoperable and only ligation of the carotid artery was performed. Cushing understood the limitations of this approach and advised the need for a more thorough understanding of aneurysm pathology before further consideration could be given to the surgical treatment of cerebral aneurysms. Despite his focus on brain tumors, Cushing's contributions to the discipline of neurovascular surgery are of great importance. With the assistance of Sir Charles Symonds, Cushing described the syndrome of subarachnoid hemorrhage. He considered inserting muscle strips into cerebral aneurysms to promote aneurysm sac thrombosis and designed the "silver clip," which was modified by McKenzie and later used by Dandy to clip the first intracranial aneurysm. Cushing was the first surgeon to wrap aneurysms in muscle fragments to prevent recurrent hemorrhage. He established the foundation on which pioneers such as Norman Dott and Walter Dandy launched the modern era of neurovascular surgery.

  3. 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.

  4. [Interesting radiological and pathological findings of the internal carotid artery observed in a case of cavernous sinusitis (author's transl)].

    PubMed

    Moriyama, T; Fujita, Y; Ono, H; Mori, K

    1977-06-01

    A 47-year-old man was admitted to the neurosurgical department of Nagasaki University Hospital with complaints of high fever, deteriorated conciousness and nonpulsating exophthalmus on the left side. The first carotid angiography which had been done 2 days prior to admission, showed only an irregular narrowing in the cavernous portion of the left carotid artery. The right carotid angiogram did not show any recognizable abnormality. The second angiography which was performed 4 days after the admission, revealed an cylindrical aneurysmal opacification about 0.8 cm in diameter in the left intracavernous portion. The right angiography could not be done at that time. On the 47th hospital day, the third angiogram was performed. There noted again, the aneurysmal opacification in the left carotid artery and furthermore, the right carotid artery was occluded completely at its entrance into the cavernous sinus. On post-mortem examination, the cavernous sinus was filled with coagulated blood which drived from the ruptured left internal carotid artery. Microscopic examination revealed marked invasion of leucocytes to the wall of the internal carotid artery at the cavernous portion in both sides. These findings suggested that a mycotic aneurysm which resulted from the cavernous sinusitis ruptured into the left cavernous sinus and spelled blood compressed the opposite (right) carotid artery within the carvernous sinus which resulted in occlusion of the artery.

  5. Treatment of acute cervical internal carotid artery dissection using the Solitaire FR revascularization device.

    PubMed

    To, Chiu Yuen; Badr, Yaser; Richards, Boyd

    2013-11-01

    During treatment of a right internal carotid artery terminus aneurysm, an acute iatrogenic flow limiting dissection was caused in the cervical internal carotid. The true lumen was catheterized using a Mirage 0.008 microwire over an Excelsior SL-10 microcatheter, which was exchanged for a Marksman microcatheter. A 6 mm × 30 mm Solitaire FR revascularization device was then deployed across the dissection as a salvage technique.

  6. Treatment of acute cervical internal carotid artery dissection using the Solitaire FR revascularization device.

    PubMed

    To, Chiu Yuen; Badr, Yaser; Richards, Boyd

    2012-12-19

    During treatment of a right internal carotid artery terminus aneurysm, an acute iatrogenic flow limiting dissection was caused in the cervical internal carotid. The true lumen was catheterized using a Mirage 0.008 microwire over an Excelsior SL-10 microcatheter, which was exchanged for a Marksman microcatheter. A 6 mm×30 mm Solitaire FR revascularization device was then deployed across the dissection as a salvage technique.

  7. Endovascular treatment of carotid cavernous sinus fistula: A systematic review

    PubMed Central

    Korkmazer, Bora; Kocak, Burak; Tureci, Ercan; Islak, Civan; Kocer, Naci; Kizilkilic, Osman

    2013-01-01

    Carotid cavernous sinus fistulas are abnormal communications between the carotid system and the cavernous sinus. Several classification schemes have described carotid cavernous sinus fistulas according to etiology, hemodynamic features, or the angiographic arterial architecture. Increased pressure within the cavernous sinus appears to be the main factor in pathophysiology. The clinical features are related to size, exact location, and duration of the fistula, adequacy and route of venous drainage and the presence of arterial/venous collaterals. Noninvasive imaging (computed tomography, magnetic resonance, computed tomography angiography, magnetic resonance angiography, Doppler) is often used in the initial work-up of a possible carotid cavernous sinus fistulas. Cerebral angiography is the gold standard for the definitive diagnosis, classification, and planning of treatment for these lesions. The endovascular approach has evolved as the mainstay therapy for definitive treatment in situations including clinical emergencies. Conservative treatment, surgery and radiosurgery constitute other management options for these lesions. PMID:23671750

  8. A systematic review of pipeline embolization device for giant intracranial aneurysms.

    PubMed

    Lv, Xianli; Ge, Huijian; He, Hongwei; Jiang, Chuhan; Li, Youxiang

    2017-01-01

    The experience with respect to the treatment of giant intracranial aneurysms with flow-diversion devices is limited. The aim of the present systematic review was to evaluate the effect of the pipeline embolization device (PED) on giant intracranial aneurysms. Eligible related articles were identified by searching the PubMed, Web of Science, Springer, ScienceDirect, and OVID databases using "giant aneurysm" and "pipeline" as the search items. The date of the last search was November 20, 2015. This systematic review adopted the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. In a total of 9 eligible studies with 200 patients and 215 aneurysms, 40 (18.6%) giant (aneurysm diameter >25mm) intracranial aneurysms treated with PED were analyzed. During a 6 to 34 month follow-up, complete occlusion was achieved in 23 (57.5%) cases. Seven patients (17.5%) developed intracranial hemorrhage, 5 developed ischemic attack (12.5%), and 13 (32.5%) developed a mass effect after PED treatment. The complication rate was 77.8% in PED for giant vertebrobasilar artery aneurysms. The cumulative mortality rate for giant paraclinoid carotid artery and middle cerebral artery aneurysms was 13.3% and increased up to 50% for giant vertebrobasilar artery aneurysms. The complete obliteration rate of PED for giant intracranial aneurysms was approximately 60%. Mass effect is the most mechanism of complications. Complication and mortality rates associated with PED for giant vertebrobasilar artery aneurysms are still extremely high.

  9. Intraoperative rupture in the surgical treatment of patients with intracranial aneurysms.

    PubMed

    Chen, S F; Kato, Y; Kumar, A; Tan, G W; Oguri, D; Oda, J; Watabe, T; Imizu, S; Sano, H; Wang, Z X

    2016-12-01

    Intraoperative rerupture (IOR) during clipping of cerebral aneurysms is a difficult complication of microneurosurgery. The aim of this study was to evaluate the incidence of IOR and analyze the strategies for controlling profound hemorrhage. A total of 165 patients with unruptured intracranial aneurysms and 46 patients with subarachnoid hemorrhage (SAH) treated surgically between April 2010 and March 2011, were reviewed. The data were collected with regard to age, sex, presence of symptoms, confounding factors and strategy for controlling intraoperative hemorrhage was analyzed in terms of location of aneurysms, timing of rupture and severity of IOR. 211 patients with 228 aneurysms were treated in this series. There were a total of six IORs which represented an IOR rate of 2.84% per patient and 2.63% per aneurysm. The highest ruptures rates occurred in patients with internal carotid artery aneurysms (25%). Surgeries in the group with ruptured aneurysms had a much higher rate of IOR compared with surgeries in the group with unruptured aneurysms. Of the six IOR aneurysms, one occurred during predissection, four during microdissection and one during clipping. One was major IOR, three were moderate and two were minor. Intraoperative rupture of an intracranial aneurysm can be potentially devastating in vascular neurosurgery. Aneurysm location, presence of SAH and surgical experience of the operating surgeon seem to be important factors affecting the incidence of IOR.

  10. Validation of Blood Flow Simulations in Intracranial Aneurysms

    NASA Astrophysics Data System (ADS)

    Yu, Yue; Anor, Tomer; Baek, Hyoungsu; Jayaraman, Mahesh; Madsen, Joseph; Karniadakis, George

    2010-11-01

    Catheter-based digital subtraction angiography (DSA) is the most accurate diagnostic procedure for investigating vascular anomalies and cerebral blood flow. Here we describe utilization of DSA in a patient with an intracranial aneursysm to validate corresponding spectral element simulations. Subsequently, we examine via visualization the structure of flow in internal carotid arteries laden with three different types of aneurysms: (1) a wide-necked saccular aneurysm, (2) a narrower-necked saccular aneurysm, and (3) a case with two adjacent saccular aneurysms. We have found through high resolution simulations that in cases (1) and (3) in physiological conditions a hydrodynamic instability occurs during the decelerating systolic phase resulting in a high frequency oscillation (20-50 Hz). We use the in-silico dye visualization to discriminate among different physical mechanisms causing the instability and contrast their effect with case (2) for which an instability arises only at much higher flowrates.

  11. Relationship of A1 segment hypoplasia to anterior communicating artery aneurysm morphology and risk factors for aneurysm formation.

    PubMed

    Rinaldo, Lorenzo; McCutcheon, Brandon A; Murphy, Meghan E; Bydon, Mohamad; Rabinstein, Alejandro A; Lanzino, Giuseppe

    2016-09-30

    OBJECTIVE Hypoplasia of the A1 segment of the anterior cerebral artery is frequently observed in patients with anterior communicating artery (ACoA) aneurysms. The effect of this anatomical variant on ACoA aneurysm morphology is not well understood. METHODS Digital subtraction angiography images were reviewed for 204 patients presenting to the authors' institution with either a ruptured or an unruptured ACoA aneurysm. The ratio of the width of the larger A1 segment to the smaller A1 segment was calculated. Patients with an A1 ratio greater than 2 were categorized as having A1 segment hypoplasia. The relationship of A1 segment hypoplasia to both patient and aneurysm characteristics was then assessed. RESULTS Of 204 patients that presented with an ACoA aneurysm, 34 (16.7%) were found to have a hypoplastic A1. Patients with A1 segment hypoplasia were less likely to have a history of smoking (44.1% vs 62.9%, p = 0.0410). ACoA aneurysms occurring in the setting of a hypoplastic A1 were also found to have a larger maximum diameter (mean 7.7 vs 6.0 mm, p = 0.0084). When considered as a continuous variable, increasing A1 ratio was associated with decreasing aneurysm dome-to-neck ratio (p = 0.0289). There was no significant difference in the prevalence of A1 segment hypoplasia between ruptured and unruptured aneurysms (18.9% vs 10.7%; p = 0.1605). CONCLUSIONS Our results suggest that a hypoplastic A1 may affect the morphology of ACoA aneurysms. In addition, the relative lack of traditional risk factors for aneurysm formation in patients with A1 segment hypoplasia argues for the importance of hemodynamic factors in the formation of ACoA aneurysms in this anatomical setting.

  12. Flow instability and wall shear stress variation in intracranial aneurysms

    PubMed Central

    Baek, H.; Jayaraman, M. V.; Richardson, P. D.; Karniadakis, G. E.

    2010-01-01

    We investigate the flow dynamics and oscillatory behaviour of wall shear stress (WSS) vectors in intracranial aneurysms using high resolution numerical simulations. We analyse three representative patient-specific internal carotid arteries laden with aneurysms of different characteristics: (i) a wide-necked saccular aneurysm, (ii) a narrower-necked saccular aneurysm, and (iii) a case with two adjacent saccular aneurysms. Our simulations show that the pulsatile flow in aneurysms can be subject to a hydrodynamic instability during the decelerating systolic phase resulting in a high-frequency oscillation in the range of 20–50 Hz, even when the blood flow rate in the parent vessel is as low as 150 and 250 ml min−1 for cases (iii) and (i), respectively. The flow returns to its original laminar pulsatile state near the end of diastole. When the aneurysmal flow becomes unstable, both the magnitude and the directions of WSS vectors fluctuate at the aforementioned high frequencies. In particular, the WSS vectors around the flow impingement region exhibit significant spatio-temporal changes in direction as well as in magnitude. PMID:20022896

  13. Transient stenotic-like occlusions as a possible mechanism for renovascular hypertension due to aneurysm.

    PubMed

    Heflin, Linden A; Street, Carrie B; Papavassiliou, Dimitrios V; Kem, David C; Wu, Dee H; O'Rear, Edgar A

    2009-01-01

    The pathophysiologic basis of hypertension secondary to a renal artery aneurysm has not been established. Changes in renal artery geometry and resultant hemodynamic alterations activate the renin-angiotensin-aldosterone system and lead to hypertension. Hemodynamic pressure losses created by blood flowing through an abnormally structured renal artery with an aneurysm predictably would provoke a similar circumstance. The present study provides a hemodynamic rationale for this hypothesis. Using computational fluid dynamics, we have modeled renal flow for selected aneurysmal geometries. These studies reveal that pressure loss across the renal artery does not change ( approximately 0.9 mm Hg) significantly when a nondeformable aneurysm is interposed on the system. The calculations, however, demonstrate that the pressure on the aneurysm walls supports the presence of forces deforming and thereby obstructing the renal artery. A deformed wall was assumed and various degrees of occlusion were modeled. A partial occlusion of 60% resulted in a renal artery pressure loss of approximately 10 mm Hg. These simulations, when applied to aneurysms at various locations on the renal artery and with various degrees of occlusion, consistently resulted in pathologically relevant pressure losses. These findings lead to a new hypothesis of how aneurysms are associated with renovascular hypertension.

  14. [Popliteal aneurysms].

    PubMed

    Vaquero Morillo, F; Zorita Calvo, A; Fernández-Samos Gutiérrez, R; García Vázquez, J; Ortega Martín, J M; Fernández Morán, C

    1992-01-01

    We presented the review of 22 cases of popliteal aneurysms with a follow-time of three years. One case was a woman and 5 cases were bilaterals. The most part of cases begun as a latter acute ischemia. Sixteen cases were treated surgically, with a null rate of mortality, 2 amputations, 4 cases of residual intermittent claudication and 10 no-symptomatic patients, with present distal pulses. Etiology, clinical presentation, diagnosis, technics and results are presented and a comparison with other authors is made. Our experience support an interventionist attitude in cases of elderly nonsymptomatic patients, performed by internal way and saphenous vein substitution.

  15. Carotid labyrinth of amphibians.

    PubMed

    Kusakabe, Tatsumi

    2002-11-01

    The amphibian carotid labyrinth is a characteristic maze-like vascular expansion at the bifurcation of the common carotid artery into the internal and external carotid arteries. The carotid labyrinths of anurans are spherical and those of urodeles are oblong. In the intervascular stroma of both anuran and urodelan carotid labyrinths, the glomus cells (type I cells, chief cells) are distributed singly or in clusters between connective tissue cells and smooth muscle cells. In fluorescence histochemistry, the glomus cells emit intense fluorescence for biogenic monoamines. In fine structure, the glomus cells are characterized by a number of dense-cored vesicles in their cytoplasm. The glomus cells have long, thin cytoplasmic processes, some of which are closely associated with smooth muscle cells, endothelial cells, and pericytes. Afferent, efferent, and reciprocal synapses are found on the glomus cells. The morphogenesis of the carotid labyrinth starts in the larvae at the point where the carotid arch descends to the internal gills. Through the early stages of larval development, the slightly expanded region of the external carotid artery becomes closely connected with the carotid arch. By the end of the foot stage, the expanded region becomes globular, and at the final stage of metamorphosis the carotid labyrinth is close to its adult form. In fine structure, the glomus cells appear as early as the initial stage of larval development. At the middle stages of development, the number of dense-cored vesicles increases remarkably. Distinct afferent synapses are found in juveniles, although efferent synapses can be seen during metamorphosis. The carotid labyrinth is innervated by nerve fibers containing several kinds of regulatory neuropeptides. Double-immunolabeling in combination with a multiple dye filter system demonstrates the coexistence of two different neuropeptides. The amphibian carotid labyrinth has been electrophysiologically confirmed to have arterial chemo

  16. Removal of the anterior clinoid process for exposure of the proximal intracranial carotid artery.

    PubMed

    Nutik, S L

    1988-10-01

    The anatomy of the carotid artery at the level of the anterior clinoid process was studied in autopsy specimens and at surgery. Marking clips placed at surgery were used to correlate anatomical and angiographic findings. Removal of the anterior clinoid process permits visualization of approximately 6 mm more of the proximal internal carotid artery without entering the cavernous sinus. The exposure reaches just to the hairpin bend of the carotid siphon, but the bend is not seen. The curve in the carotid artery which is observed after anterior clinoid removal is distal to the hairpin turn and corresponds to a bend seen on the anteroposterior projection of the angiogram. Temporary occlusion of the carotid artery proximal to a paraclinoid aneurysm is possible after clinoid removal. Complications of the removal include trauma to the third nerve and cerebrospinal fluid rhinorrhea.

  17. Living with Carotid Artery Disease

    MedlinePlus

    ... from the NHLBI on Twitter. Living With Carotid Artery Disease If you have carotid artery disease, you can take steps to manage the ... treatment plan, and getting ongoing care. Having carotid artery disease raises your risk of having a stroke . ...

  18. What Is Carotid Artery Disease?

    MedlinePlus

    ... from the NHLBI on Twitter. What Is Carotid Artery Disease? Carotid artery disease is a disease in ... blood to your face, scalp, and neck. Carotid Arteries Figure A shows the location of the right ...

  19. Endovascular Broad-Neck Aneurysm Creation in a Porcine Model Using a Vascular Plug

    SciTech Connect

    Muehlenbruch, Georg Nikoubashman, Omid; Steffen, Bjoern; Dadak, Mete; Palmowski, Moritz; Wiesmann, Martin

    2013-02-15

    Ruptured cerebral arterial aneurysms require prompt treatment by either surgical clipping or endovascular coiling. Training for these sophisticated endovascular procedures is essential and ideally performed in animals before their use in humans. Simulators and established animal models have shown drawbacks with respect to degree of reality, size of the animal model and aneurysm, or time and effort needed for aneurysm creation. We therefore aimed to establish a realistic and readily available aneurysm model. Five anticoagulated domestic pigs underwent endovascular intervention through right femoral access. A total of 12 broad-neck aneurysms were created in the carotid, subclavian, and renal arteries using the Amplatzer vascular plug. With dedicated vessel selection, cubic, tubular, and side-branch aneurysms could be created. Three of the 12 implanted occluders, two of them implanted over a side branch of the main vessel, did not induce complete vessel occlusion. However, all aneurysms remained free of intraluminal thrombus formation and were available for embolization training during a surveillance period of 6 h. Two aneurysms underwent successful exemplary treatment: one was stent-assisted, and one was performed with conventional endovascular coil embolization. The new porcine aneurysm model proved to be a straightforward approach that offers a wide range of training and scientific applications that might help further improve endovascular coil embolization therapy in patients with cerebral aneurysms.

  20. [Cerebral hemodynamics in patients with neurosensory hearing loss before and after magnetotherapy].

    PubMed

    Morenko, V M; Enin, I P

    2001-01-01

    Magnetotherapy effects on cerebral hemodynamics were studied using rheoencephalography (REG). When the treatment results and changes in cerebral hemodynamics were compared it was evident that normalization or improvement of vascular status in vertebrobasilar and carotid territories registered at REG results in better hearing. This confirms the role of vascular factor in pathogenesis of neurosensory hypoacusis of different etiology and effectiveness of magnetotherapy in such patients.

  1. Morphological age-dependent development of the human carotid bifurcation.

    PubMed

    Seong, Jaehoon; Lieber, Baruch B; Wakhloo, Ajay K

    2005-03-01

    The unique morphology of the adult human carotid bifurcation and its sinus has been investigated extensively, but its long-term, age-dependent development has not. It is important fundamentally and clinically to understand the hemodynamics and developmental forces that play a role in remodeling of the carotid bifurcation and maturation of the sinus in association with brain maturation. This understanding can lead to better prognostication and therapy of carotid disease. We analyzed the change of sinus morphology and the angle of the carotid bifurcation in four postnatal developmental stages (Group I: 0-2 years, Group II: 3-9 years, Group III: 10-19 years, and Group IV: 20-36 years, respectively) using multiprojection digital subtraction angiograms and image post-processing techniques. The most significant findings are the substantial growth of the internal carotid artery (ICA) with age and the development of a carotid sinus at the root of the ICA during late adolescence. The bifurcation angle remains virtually unchanged from infancy to adulthood. However, the angle split between the ICA and external carotid artery (ECA) relative to the common carotid artery (CCA) undergoes significant changes. Initially, the ICA appears to emanate as a side branch. Later in life, to reduce hydraulic resistance in response to increased flow demand by the brain, the bifurcation is remodeled to a construct in which both daughter vessels are a skewed continuation of the parent artery. This study provides a new analysis method to examine the development of the human carotid bifurcation over the developmental years, despite the small and sparse database. A larger database will enable in the future a more extensive analysis such as gender or racial differences.

  2. Vorticity dynamics in an intracranial aneurysm

    NASA Astrophysics Data System (ADS)

    Le, Trung; Borazjani, Iman; Sotiropoulos, Fotis

    2008-11-01

    Direct Numerical Simulation is carried out to investigate the vortex dynamics of physiologic pulsatile flow in an intracranial aneurysm. The numerical solver is based on the CURVIB (curvilinear grid/immersed boundary method) approach developed by Ge and Sotiropoulos, J. Comp. Physics, 225 (2007) and is applied to simulate the blood flow in a grid with 8 million grid nodes. The aneurysm geometry is extracted from MRI images from common carotid artery (CCA) of a rabbit (courtesy Dr.Kallmes, Mayo Clinic). The simulation reveals the formation of a strong vortex ring at the proximal end during accelerated flow phase. The vortical structure advances toward the aneurysm dome forming a distinct inclined circular ring that connects with the proximal wall via two long streamwise vortical structures. During the reverse flow phase, the back flow results to the formation of another ring at the distal end that advances in the opposite direction toward the proximal end and interacts with the vortical structures that were created during the accelerated phase. The basic vortex formation mechanism is similar to that observed by Webster and Longmire (1998) for pulsed flow through inclined nozzles. The similarities between the two flows will be discussed and the vorticity dynamics of an aneurysm and inclined nozzle flows will be analyzed.This work was supported in part by the University of Minnesota Supercomputing Institute.

  3. 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.

  4. 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.

  5. Balloon-assisted guide catheter positioning to overcome extreme cervical carotid tortuosity: technique and case experience

    PubMed Central

    Peeling, Lissa; Fiorella, David

    2014-01-01

    Background and significance We describe a method by which to efficiently and atraumatically achieve distal positioning of a flexible guiding catheter beyond extreme cervical tortuosity using a hypercompliant temporary occlusion balloon. Methods A retrospective review of a prospective neuroendovascular database was used to identify cases in which a hypercompliant balloon catheter (Hyperform or Hyperglide, ev3/Covidien, Irvine, California, USA; Scepter or Scepter XC, Alisa Viejo, California, USA) was used to achieve distal positioning of a flexible guiding catheter (Navion, ev3/Covidien, Irvine, California, USA; Neuron, Penumbra Inc, Alameda, California, USA). After achieving a stable guiding sheath position within the proximal cervical carotid artery, a hypercompliant balloon catheter was manipulated beyond the tortuous cervical internal carotid segment into the distal carotid artery. The balloon was then inflated to anchor it distally within an intracranial (cavernous or petrous) segment of the internal carotid artery. The guiding catheter was then advanced beyond the tortuous cervical segment, over the balloon catheter, as gentle counter traction was applied to the balloon. Results Balloon-assisted guiding catheter placement was used to perform endovascular treatments of 12 anterior circulation aneurysms. One patient underwent coiling alone. Five patients underwent balloon-assisted coiling. One patient underwent balloon and stent assisted coil embolization. Four patients with five carotid aneurysms (one with bilateral carotid aneurysms) underwent vascular reconstruction with the pipeline embolization device. All patients had severe tortuosity of the extracranial carotid system. Three patients had findings consistent with cervical carotid fibromuscular dysplasia. The technique was successful each time it was attempted. No parent artery dissections or catheter induced vasospam were noted in any case. Discussion Hypercompliant balloon catheters can be reliably used

  6. Giant intracranial aneurysms: morphology and clinical presentation.

    PubMed

    dos Santos, Marcio L Tostes; Spotti, Antonio Ronaldo; dos Santos, Rosangela M Tostes; Borges, Moacir Alves; Ferrari, Antonio Fernandes; Colli, Benedicto Oscar; Tognola, Waldir Antônio

    2013-01-01

    The purpose of this study was to correlate the morphology of giant intracranial aneurysms (GIA) with their clinical presentation. Eighty patients with GIA, 14 males and 66 females, were studied. Univariate and multivariate analyses were made to test the associations between morphological and clinical features. The main locations of the unruptured GIA included the carotid cavernous segment, and for the ruptured GIA, the most frequent were the carotid supraclinoid and middle cerebral arteries. There was a significant association among communicating arteries (CA) of "bad" quality and presence of thrombus and calcification (TC). The risk of rupture is 8 times higher in patients with CA of "bad" quality and 11 times higher in patients without TC. GIA are more frequent in the cavernous segment. There is a high rupture risk in the middle cerebral artery. CA of "bad" quality are associated with TC. The rupture risk is significantly higher in patients without TC.

  7. [The management of carotid reestenosis--an experience with the conventional surgery].

    PubMed

    Martins, Carlos; Almeida, Paulo; Castelobranco, Orlanda; Romero, Madalena; Cabral, Gonçalo; Dinis da Gama, A

    2010-01-01

    The authors report a series of 26 consecutive patients, 20 men and 6 women, age range 47-80 years, average age of 66 years, who underwent conventional surgery for the treatment of carotid reestenosis. The surgical management consisted in the resection of a segment of the common carotid-internal carotid arteries and interposition of a prosthetic graft, followed by ligation of the external carotid, in 3 patients; in the remainder 23 cases a venous bypass graft was interposed from the common carotid to the internal carotid artery, above the lesion, with preservation of the external carotid artery flow and ligation of the internal carotid, just below the anastomosis. There was no operative mortality and the significant morbility consisted in a cervical hematoma in one patient, transient disphonia in two cases and transient disphagia in one patient. During the mean follow up time of 43 months, one patient developed a significant reestenosis of the venous graft and another patient developed an aneurysm of the venous graft, both conditions requiring surgical repair. Based on the early and late results of this experience, the authors elect the open conventional surgery as the method of choice for the treatment of carotid reestenosis.

  8. Management of carotid stenosis. History and today

    PubMed Central

    Jargiełło, Tomasz; Drelich-Zbroja, Anna

    2013-01-01

    Internal carotid stenosis constitutes a significant clinical challenge, since it is the cause of 20–25% of ischemic brain strokes. The management of the internal carotid stenosis for many years has been raising controversies amongst neurologists, vascular surgeons and interventional radiologists mainly due to the introduction of endovascular stenting as an alternative to surgical treatment. Its application, however, requires knowledge of specific selection criteria for this kind of treatment as well as of the methods of monitoring patients after stent implantation into the internal carotid artery. Duplex Doppler ultrasound examination is currently a basis for the diagnosis of the arterial stenosis of precranial segments of the carotid arteries. It allows a reliable assessment of not only the course and morphology of the walls, but also of the hemodynamics of blood flow. Interventional treatment is applicable in patients with internal carotid stenosis of ≥70%, which is accompanied by an increase of the systolic flow velocity above 200 cm/s and the end-diastolic velocity above 50–60 cm/s in the stenotic lumen. In most cases, such a diagnosis in duplex Doppler ultrasound examination does not require any confirmation by additional diagnostic methods and if neurological symptoms are also present, it constitutes a single indication for interventional treatment. When deciding about choice of surgical or endovascular method of treatment, the following factors are of crucial importance: morphology of atherosclerotic plaque, its size, echogenicity, homogeneity of its structure, its surface and outlines. By means of ultrasound examinations, patients can be monitored after endovascular stent implantation. They enable evaluation of the degree of stent patency and allow for an early detection of symptoms indicating stenosis recurrence or presence of in-stent thrombosis. When interpreting the findings of the US checkup, it is essential to refer to the initial examination

  9. Management of carotid stenosis. History and today.

    PubMed

    Szczerbo-Trojanowska, Małgorzata; Jargiełło, Tomasz; Drelich-Zbroja, Anna

    2013-03-01

    Internal carotid stenosis constitutes a significant clinical challenge, since it is the cause of 20-25% of ischemic brain strokes. The management of the internal carotid stenosis for many years has been raising controversies amongst neurologists, vascular surgeons and interventional radiologists mainly due to the introduction of endovascular stenting as an alternative to surgical treatment. Its application, however, requires knowledge of specific selection criteria for this kind of treatment as well as of the methods of monitoring patients after stent implantation into the internal carotid artery. Duplex Doppler ultrasound examination is currently a basis for the diagnosis of the arterial stenosis of precranial segments of the carotid arteries. It allows a reliable assessment of not only the course and morphology of the walls, but also of the hemodynamics of blood flow. Interventional treatment is applicable in patients with internal carotid stenosis of ≥70%, which is accompanied by an increase of the systolic flow velocity above 200 cm/s and the end-diastolic velocity above 50-60 cm/s in the stenotic lumen. In most cases, such a diagnosis in duplex Doppler ultrasound examination does not require any confirmation by additional diagnostic methods and if neurological symptoms are also present, it constitutes a single indication for interventional treatment. When deciding about choice of surgical or endovascular method of treatment, the following factors are of crucial importance: morphology of atherosclerotic plaque, its size, echogenicity, homogeneity of its structure, its surface and outlines. By means of ultrasound examinations, patients can be monitored after endovascular stent implantation. They enable evaluation of the degree of stent patency and allow for an early detection of symptoms indicating stenosis recurrence or presence of in-stent thrombosis. When interpreting the findings of the US checkup, it is essential to refer to the initial examination

  10. Growth of Intracranial Aneurysms Arised from Curved Vessels under the Influence of Elevated Wall Shear Stress ─ A Computer Simulation Study

    NASA Astrophysics Data System (ADS)

    Feng, Yixiang; Wada, Shigeo; Tsubota, Ken-Ichi; Yamaguchi, Takami

    Recent studies have suggested that long standing elevated wall shear stress might degenerate the arterial wall and be involved in the pathogenesis of intracranial aneurysm formation and development. The present study focuses on the interplay between the hemodynamic stresses, arterial wall degeneration and deformation. By constructing a computational model and examining the hypotheses that govern the rules to grow an intracranial aneurysm, we simulate the formation and development of intracranial aneurysms. The high wall shear stress is found to propagate towards the proximal and distal end of the formed aneurysm, which becomes the key factor for the expansion of wall degeneration and aneurysm progression. The development of aneurysm is influenced by the wall shear stress threshold, the Reynolds number and the rate of wall degeneration. Our preliminary results indicate that computer simulation can be used in the study of aneurysm mechanics and yields new insight into the mechanism of aneurysm pathophysiology.

  11. Abdominal Aortic Aneurysm (AAA)

    MedlinePlus

    ... Professions Site Index A-Z Abdominal Aortic Aneurysm (AAA) Abdominal aortic aneurysm (AAA) occurs when atherosclerosis or plaque buildup causes the ... weak and bulge outward like a balloon. An AAA develops slowly over time and has few noticeable ...

  12. Abdominal aortic aneurysm

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/000162.htm Abdominal aortic aneurysm To use the sharing features on this page, ... blood to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs when an area of the aorta becomes ...

  13. Cerebral aneurysm (image)

    MedlinePlus

    ... loss of nerve function may indicate that an aneurysm may be causing pressure on adjacent brain tissue. ... changes or other neurological changes can indicate the aneurysm has ruptured and is bleeding into the brain. ...

  14. De Novo intracerebral aneurysm in a child with acquired immunodeficiency syndrome

    PubMed Central

    Bakhaidar, Mohamad G.; Ahamed, Naushad A.; Almekhlafi, Mohammed A.; Baeesa, Saleh S.

    2015-01-01

    Human immunodeficiency virus (HIV) infection associated aneurysmal vasculopathy is a rare complication of HIV infection affecting the pediatric and adult population. We present a case of a 7-year-old male child known to have a congenitally acquired HIV infection presenting with a ruptured left distal internal carotid artery fusiform aneurysm that was diagnosed on MRI scans 6 months prior to his presentation. He underwent craniotomy and successful aneurysm reconstruction. He had uncomplicated postoperative course and experienced a good recovery. This case is among the few reported pediatric cases of HIV-associated cerebral arteriopathy to undergo surgery. We also reviewed the relevant literature of this rare condition. PMID:26166600

  15. [Endovascular coiling of a «true» posterior communicating artery aneurysm].

    PubMed

    Almeida-Pérez, Rafael; Espinosa-García, Héctor; Alcalá-Cerra, Gabriel; de la Rosa-Manjarréz, Ginna; Orozco-Gómez, Fernando

    2014-01-01

    True posterior communicating artery aneurysms originate exclusively from the wall of this artery and should be differentiated from aneurysms of the posterior communicating segment of the distal carotid artery. As these lesions are rare, their anatomical relationships have been poorly described; likewise, reports concerning their endovascular treatment are extremely rare and the technical aspects poorly detailed. A case of a patient with a true aneurysm of the left posterior communicating artery treated by endovascular coiling is presented. A literature review was also conducted to illustrate the anatomical and technical details relevant to achieving its successful treatment.

  16. Subclavian artery aneurysm in a patient with vascular Ehlers-Danlos syndrome.

    PubMed

    Yasuda, Shota; Imoto, Kiyotaka; Uchida, Keiji; Uranaka, Yasuko; Kurosawa, Kenji; Masuda, Munetaka

    2016-02-01

    We describe our experience of surgical treatment in a 28-year-old woman with vascular Ehlers-Danlos syndrome. A right subclavian artery aneurysm was detected. The right vertebral artery arose from the aneurysm. Digital subtraction angiography showed interruption of the left vertebral artery. The aneurysm was excised and the right vertebral artery was anastomosed end-to-side to the right common carotid artery under deep hypothermia and circulatory arrest. The patient remained very well 4 years after surgery, with no late vascular complication.

  17. Numerical simulations of the discontinuous progression of cerebral aneurysms based on fluid-structure interactions study

    NASA Astrophysics Data System (ADS)

    Ma, Xiaoqi; Wang, Yueshe; Yu, Fangjun; Wang, Guoxiang

    2010-05-01

    Investigations into the characteristics of hemodynamics will provide a better understanding of the pathology of cerebral aneurysms for clinicians. In this work, a steady state discontinuous-growth model of the cerebral aneurysms was proposed. With the assumption of the fluid-structure interaction between the wall of blood vessel and blood, a fluid-structure coupling numerical simulation for this model was built using software ANSYS and CFX. The simulation results showed that as the aneurysm volume increased, a blood flow vortex came forth, the vortex region became asymptotically larger, and eddy density became gradually stronger in it. After the emergence of the vortex region, the blood flow in the vicinity of the downstream in the aneurysms volume turned into bifurcated flow, and the location of the flow bifurcated point was shifted with the aneurysm volume growing while directions of the shear stress applied to two sides of the bifurcated point were opposite. The Von Mises stress distribution along the wall of aneurysm volume decreased in the prior period and increased gradually in the later period. The maximum stress was in the neck of the volume and the minimum was on the distal end in the whole process of growth. It was shown that as the aneurysm increased the maximum deformation location of the aneurysm, vertical to the streamline, was transferred from the distal end of the aneurysm to its neck, then back to its distal end of the aneurysm again.

  18. Predictive modeling and in vivo assessment of cerebral blood flow in the management of complex cerebral aneurysms.

    PubMed

    Walcott, Brian P; Reinshagen, Clemens; Stapleton, Christopher J; Choudhri, Omar; Rayz, Vitaliy; Saloner, David; Lawton, Michael T

    2016-06-01

    Cerebral aneurysms are weakened blood vessel dilatations that can result in spontaneous, devastating hemorrhage events. Aneurysm treatment aims to reduce hemorrhage events, and strategies for complex aneurysms often require surgical bypass or endovascular stenting for blood flow diversion. Interventions that divert blood flow from their normal circulation patterns have the potential to result in unintentional ischemia. Recent developments in computational modeling and in vivo assessment of hemodynamics for cerebral aneurysm treatment have entered into clinical practice. Herein, we review how these techniques are currently utilized to improve risk stratification and treatment planning.

  19. Emerging Techniques for Evaluation of the Hemodynamics of Intracranial Vascular Pathology

    PubMed Central

    Huang, Melissa; Chien, Aichi

    2015-01-01

    Advances in imaging modalities have improved the assessment of intracranial hemodynamics using non-invasive techniques. This review examines new imaging modalities and clinical applications of currently available techniques, describes pathophysiology and future directions in hemodynamic analysis of intracranial stenoses, aneurysms and arteriovenous malformations and explores how hemodynamic analysis may have prognostic value in predicting clinical outcomes and assist in risk stratification. The advent of new technologies such as pseudo-continuous arterial spin labeling, accelerated magnetic resonance angiography (MRA) techniques, 4D digital subtraction angiography, and improvements in clinically available techniques such as phase-contrast MRA may change the landscape of vascular imaging and modify current clinical practice guidelines. PMID:25924168

  20. Pulsatile blood flow in Abdominal Aortic Aneurysms

    NASA Astrophysics Data System (ADS)

    Salsac, Anne-Virginie; Lasheras, Juan C.; Singel, Soeren; Varga, Chris

    2001-11-01

    We discuss the results of combined in-vitro laboratory measurements and clinical observations aimed at determining the effect that the unsteady wall shear stresses and the pressure may have on the growth and eventual rupturing of an Abdominal Aortic Aneurysm (AAA), a permanent bulging-like dilatation occurring near the aortic bifurcation. In recent years, new non-invasive techniques, such as stenting, have been used to treat these AAAs. However, the development of these implants, aimed at stopping the growth of the aneurysm, has been hampered by the lack of understanding of the effect that the hemodynamic forces have on the growth mechanism. Since current in-vivo measuring techniques lack the precision and the necessary resolution, we have performed measurements of the pressure and shear stresses in laboratory models. The models of the AAA were obtained from high resolution three-dimensional CAT/SCANS performed in patients at early stages of the disease. Preliminary DPIV measurements show that the pulsatile blood flow discharging into the cavity of the aneurysm leads to large spikes of pressure and wall shear stresses near and around its distal end, indicating a possible correlation between the regions of high wall shear stresses and the observed location of the growth of the aneurysm.

  1. Contralateral Intraparenchymal Hemorrhage Following Aneurysmal Clipping

    PubMed Central

    Kim, Jae-Hoon

    2008-01-01

    Post-clipping intraparenchymal hemorrhage of the contralateral hemisphere is a very unusual phenomenon in a patient with aneurysmal subarachnoid hemorrhage, unless there is an underlying condition. We report a complicated case of 47-year-old man, who underwent uneventful clipping of ruptured aneurysm and experienced vasospasm two weeks later. Vasospasm was treated by intra-arterial nimodipine and systemic hyperdynamic therapy. One week thereafter, he became unconscious due to intraparenchymal hemorrhage on the anterior border-zone of contalateral hemisphere, but intraoperative and pathologic findings failed to disclose any vascular anomaly. We suggest that the anti-spastic regimens cause local hemodynamic redistribution through the vasodilatory effect and in turn, resulted in such an unexpected bleeding. PMID:19096626

  2. The Pterional Approach and Extradural Anterior Clinoidectomy to Clip Paraclinoid Aneurysms

    PubMed Central

    Kim, Jung Soo; Jeon, Kyoung Dong; Choi, Byeong Sam

    2013-01-01

    Objective The surgical clipping of paraclinoid segment internal carotid artery aneurysms is considered difficult because of the complex anatomical location and important neighboring structures. Our experiences of pterional craniotomy and extradural anterior clinoidectomy (EAC) to clip paraclinoid aneurysms are reported herein. Methods We present two patients with paraclinoid aneurysms who underwent surgical clipping using pterional craniotomy and EAC. The clinical results and operative techniques were reviewed from the patients' medical records. Results EAC improves the surgical field in the suprasellar and periclinoid regions. Clinically, a good outcome was obtained in both cases. No surgical complications directly resulting from the EAC were observed. Conclusion Favorable surgical results can be obtained with pterional craniotomy and EAC for the clipping of paraclinoid aneurysms. EAC is advocated for the clipping of paraclinoid aneurysms. PMID:24167811

  3. The Use of Flow Diversion for the Treatment of Intracranial Aneurysms: Expansion of Indications

    PubMed Central

    Brouillard, Adam M; Sun, Xingwen; Siddiqui, Adnan H

    2016-01-01

    Flow diversion is a novel concept for treating anatomically challenging intracranial aneurysms and has gained increasing acceptance. Flow diverter stents, such as the Pipeline Embolization Device (PED) (ev3-Covidien, Irvine, CA, USA), are approved for treating unruptured large and giant aneurysms from the internal carotid artery between the superior hypophyseal and cavernous segments. However, technological advances and recent clinical results suggest that flow diversion can be safely and effectively used in treating ruptured aneurysms, posterior circulation aneurysms, and distal anterior circulation aneurysms. In this brief review, we aim to investigate the recent evidence on the utilization of PEDs in these controversial vascular territories and to discuss whether the indications for flow diversion can be expanded.   PMID:26973807

  4. Management of carotid Dacron patch infection: a case report using median sternotomy for proximal common carotid artery control and in situ polytetrafluoroethylene grafting.

    PubMed

    Illuminati, Giulio; Calio', Francesco G; D'Urso, Antonio; Ceccanei, Gianluca; Pacilè, Maria Antonietta

    2009-01-01

    We report on a 58-year-old male who presented with an enlarging cervical hematoma 3 months following carotid endarterectomy with Dacron patch repair, due to septic disruption of the Dacron patch secondary to presumed infection. The essential features of this case are the control of the proximal common carotid artery gained through a median sternotomy, because the patient was markedly obese with minimal thyromental distance, and the treatment consisting of in situ polytetrafluoroethylene bypass grafting, due to the absence of a suitable autogenous saphenous vein. Median sternotomy is rarely required in case of reintervention for septic false aneurysms and hematomas following carotid endarterectomy but should be considered whenever difficult control of the common carotid artery, when entering the previous cervicotomy, is anticipated. In situ polytetrafluoroethylene grafting can be considered if autogenous vein material is lacking.

  5. Benefits of using dexmedetomidine during carotid endarterectomy: A review

    PubMed Central

    Nair, Abhijit S.

    2014-01-01

    As per current recommendation, patients with acute ischemic stroke should be offered carotid endarterectomy (CEA) within 24-72 hours. The same applies to patients with recurrent transient ischemic attacks (TIA). This time is usually less for hemodynamic optimization of patients who’ve suffered acute ischemic stroke. Hence’ they are hemodynamically labile and can have accelerated hypertension on induction/extubation. This can have disastrous outcomes. It is a common practice among anesthesiologists to avoid angiotensin converting enzyme(ACE) inhibitors or angiotensin receptor blockers on the day of surgery. This also adds to hypertensive issues perioperatively. Dexmedetomidine is a wonderful drug which can be used during CEA. Due to its centrally mediated sympatholytic effect, it confers good hemodynamic control during induction, intraoperatively, and during extubation. We did a search on PubMed and Google for carotid endarterectomies done under general and locoregional anesthesia during which dexmedetomidine was used. The keywords used by us during the search were as follows: anesthesia, carotid endarterectomy, anesthesia. We also searched for use of dexmedetomidine infusion to attenuate hypertensive response to intubation and for providing stability in major surgeries like CABG, craniotomies, bariatric surgeries, and valve replacements. PMID:24843344

  6. Obesity and carotid artery remodeling

    PubMed Central

    Kozakova, M; Palombo, C; Morizzo, C; Højlund, K; Hatunic, M; Balkau, B; Nilsson, P M; Ferrannini, E

    2015-01-01

    Background/Objective: The present study tested the hypothesis that obesity-related changes in carotid intima-media thickness (IMT) might represent not only preclinical atherosclerosis but an adaptive remodeling meant to preserve circumferential wall stress (CWS) in altered hemodynamic conditions characterized by body size-dependent increase in stroke volume (SV) and blood pressure (BP). Subjects/Methods: Common carotid artery (CCA) luminal diameter (LD), IMT and CWS were measured in three different populations in order to study: (A) cross-sectional associations between SV, BP, anthropometric parameters and CCA LD (266 healthy subjects with wide range of body weight (24–159 kg)); (B) longitudinal associations between CCA LD and 3-year IMT progression rate (ΔIMT; 571 healthy non-obese subjects without increased cardiovascular (CV) risk); (C) the impact of obesity on CCA geometry and CWS (88 obese subjects without CV complications and 88 non-obese subjects matched for gender and age). Results: CCA LD was independently associated with SV that was determined by body size. In the longitudinal study, baseline LD was an independent determinant of ΔIMT, and ΔIMT of subjects in the highest LD quartile was significantly higher (28±3 μm) as compared with those in the lower quartiles (8±3, 16±4 and 16±3 μm, P=0.001, P<0.05 and P=0.01, respectively). In addition, CCA CWS decreased during the observational period in the highest LD quartile (from 54.2±8.6 to 51.6±7.4 kPa, P<0.0001). As compared with gender- and age-matched lean individuals, obese subjects had highly increased CCA LD and BP (P<0.0001 for both), but only slightly higher CWS (P=0.05) due to a significant increase in IMT (P=0.005 after adjustment for confounders). Conclusions: Our findings suggest that in obese subjects, the CCA wall thickens to compensate the luminal enlargement caused by body size-induced increase in SV, and therefore, to normalize the wall stress. CCA diameter in obesity could

  7. Computational fluid dynamics of blood flow in coil-embolized aneurysms: effect of packing density on flow stagnation in an idealized geometry.

    PubMed

    Otani, Tomohiro; Nakamura, Masanori; Fujinaka, Toshiyuki; Hirata, Masayuki; Kuroda, Junko; Shibano, Katsuhiko; Wada, Shigeo

    2013-08-01

    Coil embolization is performed to induce flow stagnation in cerebral aneurysms and enhance blood clot formation, thus preventing rupture and further growth. We investigated hemodynamics in differently positioned aneurysms coiled at various packing densities to determine the effective packing density in terms of flow stagnation. As a first step, hemodynamic simulations were conducted for idealized geometries of both terminal- and sidewall-type aneurysms. Porous media modeling was employed to describe blood flow in coil-embolized aneurysms. The stagnant volume ratio (SVR) was analyzed to quantify the efficacy of coil embolization. Regardless of aneurysm type and angle, SVR increased with increasing packing density, but the increase in SVR varied depending on type. For sidewall-type aneurysms, the packing density required to achieve 60 % SVR was 20 %, roughly independent of aneurysm angle; flow stagnation was achieved at low packing density. In contrast, in terminal-type aneurysms, the packing density required to achieve 60 % SVR was highly dependent on aneurysm angle, accomplishing a 20 % packing density only for lower angles. Indications are that a relatively high packing density would be required, particularly when these aneurysms are angled against the parent artery. The packing density required for flow stagnation varies depending on aneurysm type and relative position.

  8. Assessment of shear stress related parameters in the carotid bifurcation using mouse-specific FSI simulations.

    PubMed

    De Wilde, David; Trachet, Bram; Debusschere, Nic; Iannaccone, Francesco; Swillens, Abigail; Degroote, Joris; Vierendeels, Jan; De Meyer, Guido R Y; Segers, Patrick

    2016-07-26

    The ApoE(-)(/)(-) mouse is a common small animal model to study atherosclerosis, an inflammatory disease of the large and medium sized arteries such as the carotid artery. It is generally accepted that the wall shear stress, induced by the blood flow, plays a key role in the onset of this disease. Wall shear stress, however, is difficult to derive from direct in vivo measurements, particularly in mice. In this study, we integrated in vivo imaging (micro-Computed Tomography-µCT and ultrasound) and fluid-structure interaction (FSI) modeling for the mouse-specific assessment of carotid hemodynamics and wall shear stress. Results were provided for 8 carotid bifurcations of 4 ApoE(-)(/)(-) mice. We demonstrated that accounting for the carotid elasticity leads to more realistic flow waveforms over the complete domain of the model due to volume buffering capacity in systole. The 8 simulated cases showed fairly consistent spatial distribution maps of time-averaged wall shear stress (TAWSS) and relative residence time (RRT). Zones with reduced TAWSS and elevated RRT, potential indicators of atherosclerosis-prone regions, were located mainly at the outer sinus of the external carotid artery. In contrast to human carotid hemodynamics, no flow recirculation could be observed in the carotid bifurcation region.

  9. Computational Fluid Dynamics Study of Bifurcation Aneurysms Treated with Pipeline Embolization Device: Side Branch Diameter Study.

    PubMed

    Tang, Abraham Yik-Sau; Chung, Wai-Choi; Liu, Eric Tian-Yang; Qu, Jie-Qiong; Tsang, Anderson Chun-On; Leung, Gilberto Ka-Kit; Leung, Kar-Ming; Yu, Alfred Cheuk-Hang; Chow, Kwok-Wing

    An intracranial aneurysm, abnormal swelling of the cerebral artery, may lead to undesirable rates of mortality and morbidity upon rupture. Endovascular treatment involves the deployment of a flow-diverting stent that covers the aneurysm orifice, thereby reducing the blood flow into the aneurysm and mitigating the risk of rupture. In this study, computational fluid dynamics analysis is performed on a bifurcation model to investigate the change in hemodynamics with various side branch diameters. The condition after the deployment of a pipeline embolization device is also simulated. Hemodynamic factors such as flow velocity, pressure, and wall shear stress are studied. Aneurysms with a larger side branch vessel might have greater risk after treatment in terms of hemodynamics. Although a stent could lead to flow reduction entering the aneurysm, it would drastically alter the flow rate inside the side branch vessel. This may result in side-branch hypoperfusion subsequent to stenting. In addition, two patient-specific bifurcation aneurysms are tested, and the results show good agreement with the idealized models. Furthermore, the peripheral resistance of downstream vessels is investigated by varying the outlet pressure conditions. This quantitative analysis can assist in treatment planning and therapeutic decision-making.

  10. Influence of stent configuration on cerebral aneurysm fluid dynamics.

    PubMed

    Babiker, M Haithem; Gonzalez, L Fernando; Ryan, Justin; Albuquerque, Felipe; Collins, Daniel; Elvikis, Arius; Frakes, David H

    2012-02-02

    Embolic coiling is the most popular endovascular treatment available for cerebral aneurysms. Nevertheless, the embolic coiling of wide-neck aneurysms is challenging and, in many cases, ineffective. Use of highly porous stents to support coiling of wide-neck aneurysms has become a common procedure in recent years. Several studies have also demonstrated that high porosity stents alone can significantly alter aneurysmal hemodynamics, but differences among different stent configurations have not been fully characterized. As a result, it is usually unclear which stent configuration is optimal for treatment. In this paper, we present a flow study that elucidates the influence of stent configuration on cerebral aneurysm fluid dynamics in an idealized wide-neck basilar tip aneurysm model. Aneurysmal fluid dynamics for three different stent configurations (half-Y, Y and, cross-bar) were first quantified using particle image velocimetry and then compared. Computational fluid dynamics (CFD) simulations were also conducted for selected stent configurations to facilitate validation and provide more detailed characterizations of the fluid dynamics promoted by different stent configurations. In vitro results showed that the Y stent configuration reduced cross-neck flow most significantly, while the cross-bar configuration reduced velocity magnitudes within the aneurysmal sac most significantly. The half-Y configuration led to increased velocity magnitudes within the aneurysmal sac at high parent-vessel flow rates. Experimental results were in strong agreement with CFD simulations. Simulated results indicated that differences in fluid dynamic performance among the different stent configurations can be attributed primarily to protruding struts within the bifurcation region.

  11. Massive Hemorrhage From Multiple Hepatic Artery Aneurysms.

    PubMed

    Kahn, S Lowell; McClain, Jonathan; Kaufman, Jeffrey L

    2016-10-01

    A 66-year-old man, with an abnormal porta hepatis, consistent with tumor or inflammation, developed massive bleeding from one of numerous hepatic artery aneurysms, and coil embolization achieved control of bleeding. He died of subsequent multisystem organ failure, and the most likely diagnosis was either polyarteritis nodosa or segmental arterial mediolysis. Although the dual hepatic blood supply allows a degree of arterial embolization, this case demonstrates the risks associated with large territory hepatic arterial embolization in the presence of hemodynamic instability. We discuss the management issues related to massive hepatic bleeding when no surgical approach is possible.

  12. Anesthetic approaches in carotid body tumor surgery

    PubMed Central

    Kavakli, Ali Sait; Ozturk, Nilgun Kavrut

    2016-01-01

    OBJECTIVE: Carotid body tumors (CBT) are benign tumors that originate from neural non-chromaffin cells that are typically localized near carotid bifurcation. Surgical removal of the tumor is the most appropriate treatment. General anesthesia is preferred anesthetic technique for CBT surgery. Basic elements of anesthetic management are protection of hemodynamic stability and maintaining cerebral perfusion pressure (CPP). The aim of this study was to evaluate anesthetic management of CBT surgery and present the literature knowledge. METHODS: The study included 10 consecutive patients with diagnosis of CBT who underwent surgery at Antalya Training and Research Hospital, in Antalya, Turkey, between 2013 and 2016. Preoperative demographic details; comorbidities; side of surgical site; duration of operation; length of intensive care unit (ICU) and hospital stay; change of intraoperative blood pressure; use of inotropic drugs, blood products, and analgesics; postoperative visual analogue scale (VAS) pain score; and complications were recorded. RESULTS: According to Shamblin classification, 3 tumors were type I and the remaining 7 were type II. Tumors were located on right side in 6 patients, and on left in 4. Blood loss sufficient to require transfusion was observed in 1 patient. Average intraoperative blood loss was 287±68 mL. Tachycardia and hypertension were observed in 1 patient; bradycardia and hypotension were seen in 4 patients. Infusion for inotropic support was administered to 1 patient. Mean duration of operation was 109±20 minutes. Mean VAS score was 4±1, mean ICU tramadol consumption was 80±25 mg. Duration of stay in ICU and hospital were 2.4±1.1 hours and 3.8±0.7 days, respectively. Mortality and neurological complications were not seen in postoperative period. CONCLUSION: CBT surgery requires close and complex anesthesia management. Protection of hemodynamic stability against sudden hemodynamic changes, monitoring, and maintaining CPP are the most

  13. Pediatric isolated bilateral iliac aneurysm.

    PubMed

    Chithra, R; Sundar, R Ajai; Velladuraichi, B; Sritharan, N; Amalorpavanathan, J; Vidyasagaran, T

    2013-07-01

    Aneurysms are rare in children. Isolated iliac artery aneurysms are very rare, especially bilateral aneurysms. Pediatric aneurysms are usually secondary to connective tissue disorders, arteritis, or mycotic causes. We present a case of a 3-year-old child with bilateral idiopathic common iliac aneurysms that were successfully repaired with autogenous vein grafts.

  14. Evaluation of hemodynamics changes during interventional stent placement using Doppler optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Vuong, Barry; Genis, Helen; Wong, Ronnie; Ramjist, Joel; Jivraj, Jamil; Farooq, Hamza; Sun, Cuiru; Yang, Victor X. D.

    2015-03-01

    Carotid atherosclerosis is a critical medical concern that can lead to ischemic stroke. Local hemodynamic patterns have also been associated with the development of atherosclerosis, particularly in regions with disturbed flow patterns such as bifurcations. Traditionally, this disease was treated using carotid endarterectomy, however recently there is an increasing trend of carotid artery stenting due to its minimally invasive nature. It is well known that this interventional technique creates changes in vasculature geometry and hemodynamic patterns due to the interaction of stent struts with arterial lumen, and is associated with complications such as distal emboli and restenosis. Currently, there is no standard imaging technique to evaluate regional hemodynamic patterns found in stented vessels. Doppler optical coherence tomography (DOCT) provides an opportunity to identify in vivo hemodynamic changes in vasculature using high-resolution imaging. In this study, blood flow profiles were examined at the bifurcation junction in the internal carotid artery (ICA) in a porcine model following stent deployment. Doppler imaging was further conducted using pulsatile flow in a phantom model, and then compared to computational fluid dynamics (CFD) simulation of a virtual bifurcation to assist with the interpretation of emphin vivo results.

  15. Internal carotid artery rupture caused by carotid shunt insertion

    PubMed Central

    Illuminati, Giulio; Caliò, Francesco G.; Pizzardi, Giulia; Vietri, Francesco

    2015-01-01

    Introduction Shunting is a well-accepted method of maintaining cerebral perfusion during carotid endarterectomy (CEA). Nonetheless, shunt insertion may lead to complications including arterial dissection, embolization, and thrombosis. We present a complication of shunt insertion consisting of arterial wall rupture, not reported previously. Presentation of case A 78-year-old woman underwent CEA combined with coronary artery bypass grafting (CABG). At the time of shunt insertion an arterial rupture at the distal tip of the shunt was detected and was repaired via a small saphenous vein patch. Eversion CEA and subsequent CABG completed the procedure whose postoperative course was uneventful. Discussion Shunting during combined CEA-CABG may be advisable to assure cerebral protection from possible hypoperfusion due to potential hemodynamic instability of patients with severe coronary artery disease. Awareness and prompt management of possible shunt-related complications, including the newly reported one, may contribute to limiting their harmful effect. Conclusion Arterial wall rupture is a possible, previously not reported, shunt-related complication to be aware of when performing CEA. PMID:26255001

  16. Finite Element Modeling of Endovascular Intervention Enables Hemodynamic Prediction of Complex Treatment Strategies for Coiling and Flow Diversion

    PubMed Central

    Damiano, Robert J.; Ma, Ding; Xiang, Jianping; Siddiqui, Adnan H.; Snyder, Kenneth V.; Meng, Hui

    2016-01-01

    Endovascular interventions using coil embolization and flow diversion are becoming the mainstream treatment for intracranial aneurysms (IAs). To help assess the effect of intervention strategies on aneurysm hemodynamics and treatment outcome, we have developed a finite-element-method (FEM)-based technique for coil deployment along with our HiFiVS technique for flow diverter (FD) deployment in patient-specific IAs. We tested four clinical intervention strategies: coiling (1–8 coils), single FD, FD with adjunctive coils (1–8 coils), and overlapping FDs. By evaluating post-treatment hemodynamics using computational fluid dynamics (CFD), we compared the flow-modification performance of these strategies. Results show that a single FD provides more reduction in inflow rate than low PD coiling, but less reduction in average velocity inside the aneurysm. Adjunctive coils add no additional reduction of inflow rate beyond a single FD until coil PD exceeds 11%. This suggests that the main role of FDs is to divert inflow, while that of coils is to create stasis in the aneurysm. Overlapping FDs decreases inflow rate, average velocity, and average wall shear stress (WSS) in the aneurysm sac, but adding a third FD produces minimal additional reduction. In conclusion, our FEM-based techniques for virtual coiling and flow diversion enable recapitulation of complex endovascular intervention strategies and detailed hemodynamics to identify hemodynamic factors that affect treatment outcome. PMID:26169778

  17. Sternum-Sparing Hybrid Repair of a Symptomatic Innominate Artery Aneurysm in a Frail Patient with Bovine Aortic Arch.

    PubMed

    Pellenc, Quentin; Avramenko, Alla; Mordant, Pierre; Castier, Yves

    2016-08-01

    We present the case of a 65-year-old man with a bovine aortic arch variation, who presented a symptomatic aneurysm of the innominate artery. Standard open repair was contraindicated and an hybrid approach was performed, regarding general status (Organisation Mondiale de la Santé (OMS) Performance Status score 3 and American Society of Anesthesiologists Physical Status classification system score 3). Right common carotid artery and right subclavian artery were revascularized surgically from the left common carotid artery. Proximal aneurysm exclusion was performed with a vascular plug. Follow-up computed tomography angiography confirmed the exclusion of the innominate artery aneurysm. Vascular plugs can be used safely through a sternum-sparing hybrid approach to treat symptomatic innominate artery aneurysms in frail patients.

  18. Two Cases of Super-Giant Coronary Aneurysms after Kawasaki Disease

    PubMed Central

    Lee, Joowon; Kwon, Bo Sang; Bae, Eun Jung; Noh, Chung Il

    2014-01-01

    Acute giant coronary aneurysm after Kawasaki disease (KD) is a catastrophic complication that can be fatal and very difficult to manage. However, no fixed consensus has been reached for the management of super-giant coronary aneurysms in the acute setting. Here, we report the successful management of young children with super-giant coronary aneurysms after KD. Based on our experience, hemodynamic stabilization to prevent further coronary dilation or rupture and strict anticoagulation to avoid thrombus formation are mandatory in the management of this condition. PMID:24497892

  19. Invasive hemodynamics of constrictive pericarditis.

    PubMed

    Doshi, Shrenik; Ramakrishnan, Sivasubramanian; Gupta, Saurabh Kumar

    2015-01-01

    Cardiac catheterization and hemodynamic study is the gold standard for the diagnosis of pericardial constriction. Careful interpretation of the hemodynamic data is essential to differentiate it from other diseases with restrictive physiology. In this hemodynamic review we shall briefly discuss the physiologic basis of various hemodynamic changes seen in a patient with constrictive pericarditis.

  20. Simulation of unsteady laminar flow in models of terminal aneurysm of the basilar artery

    NASA Astrophysics Data System (ADS)

    Valencia, Alvaro

    2005-05-01

    Blood flow dynamics play an important role in the pathogenesis and treatment of intracranial aneurysms. The evaluation of the velocity field in the aneurysm dome and neck is important for the correct placement of endovascular coils, in addition the temporal and spatial variations of wall shear stress in the aneurysm are correlated with its growth and rupture. The present numerical investigation describes the hemodynamics in two models of terminal aneurysm of the basilar artery. Aneurysm models with an aspect ratio of 1.0 and 1.67 were studied. Each model was subject to a steady, sinusoidal and physiologically representative waveform of inflow for a mean Reynolds number of 560. Symmetric and asymmetric outflow conditions in the branches were also studied.

  1. A virtual coiling technique for image-based aneurysm models by dynamic path planning.

    PubMed

    Morales, Hernán G; Larrabide, Ignacio; Geers, Arjan J; San Román, Luis; Blasco, Jordi; Macho, Juan M; Frangi, Alejandro F

    2013-01-01

    Computational algorithms modeling the insertion of endovascular devices, such as coil or stents, have gained an increasing interest in recent years. This scientific enthusiasm is due to the potential impact that these techniques have to support clinicians by understanding the intravascular hemodynamics and predicting treatment outcomes. In this work, a virtual coiling technique for treating image-based aneurysm models is proposed. A dynamic path planning was used to mimic the structure and distribution of coils inside aneurysm cavities, and to reach high packing densities, which is desirable by clinicians when treating with coils. Several tests were done to evaluate the performance on idealized and image-based aneurysm models. The proposed technique was validated using clinical information of real coiled aneurysms. The virtual coiling technique reproduces the macroscopic behavior of inserted coils and properly captures the densities, shapes and coil distributions inside aneurysm cavities. A practical application was performed by assessing the local hemodynamic after coiling using computational fluid dynamics (CFD). Wall shear stress and intra-aneurysmal velocities were reduced after coiling. Additionally, CFD simulations show that coils decrease the amount of contrast entering the aneurysm and increase its residence time.

  2. Velocity profile and wall shear stress of saccular aneurysms at the anterior communicating artery.

    PubMed

    Yamaguchi, Ryuhei; Ujiie, Hiroshi; Haida, Sayaka; Nakazawa, Nobuhiko; Hori, Tomokatsu

    2008-01-01

    It has recently been shown that the aspect ratio (dome/neck) of an aneurysm correlates well with intraaneurysmal blood flow. Aneurysms with an aspect ratio larger than 1.6 carry a higher risk of rupture. We examined the effect of aspect ratio (AR) on intra-aneurysmal flow using experimental models. Flow visualization with particle imaging velocimetry and measurement of wall shear stress using laser Doppler anemometry were performed on three different aneurysm models: AR 0.5, 1.0, and 2.0. Intraaneurysmal flow consists of inflow, circulation, and outflow. Rapid inflow impinged on the distal neck creating a stagnant point. Rapid flow and maximum wall shear stress were observed in the vicinity of the stagnant point. By changing the Reynold's number, the stagnant point moved. By increasing the AR of the aneurysm, vortices inside the aneurysm sac closed and very slow flow was observed, resulting in very low shear stress markedly at a Reynold's number of 250, compatible with the diastolic phase. In the aneurysm model AR 2.0, both rapid flow at the neck and vortices inside the aneurysm are sufficient to activate platelets, making a thrombus that may anchor on the dome where very slow flow takes place. Hemodynamics in aneurysms larger than AR 2.0 definitely contribute to thrombus formation.

  3. Thrombosis and spontaneous recanalization of a giant intracranial aneurysm: diagnostic and management pearls in a pediatric patient.

    PubMed

    Kooshkabadi, Ali; Jankowitz, Brian; Choi, Phillip A; Weiner, Gregory M; Greene, Stephanie

    2015-01-01

    The authors present the case of a boy who was successfully managed through the spontaneous thrombosis of a cavernous internal carotid artery (ICA) aneurysm, the subsequent occlusion of the ICA, its recanalization, and ultimate endovascular sacrifice, using only two angiograms because of the diagnostic capability of CT angiography. Spontaneous recanalization of the ICA following occlusion in the setting of a giant aneurysm has not been previously reported.

  4. Carotid Artery Screening

    MedlinePlus

    ... plaque and the injury it causes is called atherosclerosis . Over time, the walls of affected arteries thicken ... disease (CAD) obesity physical inactivity family history of atherosclerosis and/or stroke Screening Recommendations Carotid Duplex US ...

  5. Carotid Artery Disease

    MedlinePlus

    ... sites within the artery. This process is called atherosclerosis. Carotid arteries that are clogged with plaques are ... at greater risk of high blood pressure and atherosclerosis. High blood-fat levels. High levels of low- ...

  6. Carotid artery disease

    MedlinePlus

    ... a stroke recover most or all of their functions. Others die of the stroke itself or from complications. About half of people ... patients with extracranial carotid and vertebral artery disease: executive summary: ... American Association of Neuroscience Nurses, American Association ...

  7. 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.

  8. Direct carotid cavernous fistula after submucous resection of the nasal septum.

    PubMed

    Bizri, A R; al-Ajam, M; Zaytoun, G; al-Kutoubi, A

    2000-01-01

    A carotid cavernous fistula (CCF) is an abnormal arteriovenous anastomosis between the carotid artery and the cavernous sinus. Etiologies of this condition reported in the literature so far include facial trauma, rupture of an intracavernous aneurysm of the carotid artery, Ehler-Danlos syndrome and fibromuscular dysplasia of the cerebral arteries. Such fistulae were reported as complications of rhinoplasty, transsphenoidal surgery, embolization of cavernous sinus meningioma, and rhinocerebral mucormycosis. CCF may also occur spontaneously in children or as a congenital malformation. However, to our knowledge, submucous resection of the nasal septum has not been reported before to cause direct carotid-cavernous fistula. CT and angiographic findings are presented and a review of the literature for reported causes of CCF is made as well as a brief discussion of the possible pathophysiology.

  9. Functional hemodynamic monitoring

    PubMed Central

    Pinsky, Michael R; Payen, Didier

    2005-01-01

    Hemodynamic monitoring is a central component of intensive care. Patterns of hemodynamic variables often suggest cardiogenic, hypovolemic, obstructive, or distributive (septic) etiologies to cardiovascular insufficiency, thus defining the specific treatments required. Monitoring increases in invasiveness, as required, as the risk for cardiovascular instability-induced morbidity increases because of the need to define more accurately the diagnosis and monitor the response to therapy. Monitoring is also context specific: requirements during cardiac surgery will be different from those in the intensive care unit or emergency department. Solitary hemodynamic values are useful as threshold monitors (e.g. hypotension is always pathological, central venous pressure is only elevated in disease). Some hemodynamic values can only be interpreted relative to metabolic demand, whereas others have multiple meanings. Functional hemodynamic monitoring implies a therapeutic application, independent of diagnosis such as a therapeutic trial of fluid challenge to assess preload responsiveness. Newer methods for assessing preload responsiveness include monitoring changes in central venous pressure during spontaneous inspiration, and variations in arterial pulse pressure, systolic pressure, and aortic flow variation in response to vena caval collapse during positive pressure ventilation or passive leg raising. Defining preload responsiveness using these functional measures, coupled to treatment protocols, can improve outcome from critical illness. Potentially, as these and newer, less invasive hemodynamic measures are validated, they could be incorporated into such protocolized care in a cost-effective manner. PMID:16356240

  10. Intra-aneurysmal flow with helix and mesh stent placement across side-wall aneurysm pore of a straight parent vessel.

    PubMed

    Liou, Tong-Miin; Liou, Shun-Nan; Chu, Kai-Lung

    2004-02-01

    Pulsatile flow fields in a cerebrovascular side-wall aneurysm model with a wide ostium after stenting are presented in terms of particle tracking velocimetry measurements and flow visualization. Among the stent parameters the shape, helix versus mesh, was selected to study its effect on the changes of intraaneurysmal hemodynamics for the reference of minimally invasive endovascular aneurysm treatment. The blocking ratio of the stents was fixed at 30%. The Womersley number was 3.9 and the mean, peak, and minimal Reynolds numbers based on the bulk average velocity and diameter of the parent vessel were 600, 850, and 300, respectively. Four consecutive flow-rate phases were selected to characterize the intra-aneurysmal flow. The results are characterized in terms of velocity vector field, regional average velocity, and intra-aneurysmal vorticity/circulation/wall shear stress. It is found that the hemodynamic features inside the aneurysm alter markedly with the shape of the stent and the size of the orifice. Both stents investigated induce favorable changes in the intra-aneurysmal flow stasis as well as direction and undulation of wall shear stresses. A comparison of the results of the helix to mesh stent shows that the former is more favorable for endovascular treatment.

  11. Pipeline for uncoilable or failed aneurysms: 3-year follow-up results.

    PubMed

    Becske, Tibor; Potts, Matthew B; Shapiro, Maksim; Kallmes, David F; Brinjikji, Waleed; Saatci, Isil; McDougall, Cameron G; Szikora, István; Lanzino, Giuseppe; Moran, Christopher J; Woo, Henry H; Lopes, Demetrius K; Berez, Aaron L; Cher, Daniel J; Siddiqui, Adnan H; Levy, Elad I; Albuquerque, Felipe C; Fiorella, David J; Berentei, Zsolt; Marosföi, Miklós; Cekirge, Saruhan H; Nelson, Peter K

    2016-10-14

    OBJECTIVE The long-term effectiveness of endovascular treatment of large and giant wide-neck aneurysms using traditional endovascular techniques has been disappointing, with high recanalization and re-treatment rates. Flow diversion with the Pipeline Embolization Device (PED) has been recently used as a stand-alone therapy for complex aneurysms, showing significant improvement in effectiveness while demonstrating a similar safety profile to stent-supported coil treatment. However, relatively little is known about its long-term safety and effectiveness. Here the authors report on the 3-year safety and effectiveness of flow diversion with the PED in a prospective cohort of patients with large and giant internal carotid artery aneurysms enrolled in the Pipeline for Uncoilable or Failed Aneurysms (PUFS) trial. METHODS The PUFS trial is a prospective study of 107 patients with 109 aneurysms treated with the PED. Primary effectiveness and safety end points were demonstrated based on independently monitored 180-day clinical and angiographic data. Patients were enrolled in a long-term follow-up protocol including 1-, 3-, and 5-year clinical and imaging follow-up. In this paper, the authors report the midstudy (3-year) effectiveness and safety data. RESULTS At 3 years posttreatment, 74 subjects with 76 aneurysms underwent catheter angiography as required per protocol. Overall, complete angiographic aneurysm occlusion was observed in 71 of these 76 aneurysms (93.4% cure rate). Five aneurysms were re-treated, using either coils or additional PEDs, for failure to occlude, and 3 of these 5 were cured by the 3-year follow-up. Angiographic cure with one or two treatments of Pipeline embolization alone was therefore achieved in 92.1%. No recanalization of a previously completely occluded aneurysm was noted on the 3-year angiograms. There were 3 (2.6%) delayed device- or aneurysm-related serious adverse events, none of which led to permanent neurological sequelae. No major or minor

  12. Treatment of Complex Intracranial Aneurysms Using Flow-Diverting Silk® Stents

    PubMed Central

    Buyukkaya, Ramazan; Kocaeli, Hasan; Yildirim, Nalan; Cebeci, Hakan; Erdogan, Cüneyt; Hakyemez, Bahattin

    2014-01-01

    Summary This study describes the peri-procedural and late complications and angiographic follow-up results of 32 patients with 34 complex aneurysms treated with flow diverter Silk stents in a single centre. In this retrospective study, 40 Silk stents (SS) were implanted in 34 complex intracranial aneurysms in 32 patients. In our series, 20 (58.8%) carotid-ophthalmic internal carotid artery (ICA), six (17.6%) cavernous ICA, two (5.9%) supraclinoid ICA, two (5.9%) petrosal ICA (the same patient- bilateral) and four (11.8%) posterior circulation aneurysms were treated. One of the posterior circulation lesions was a fenestrated-type aneurysm. Twenty wide-necked, saccular; eight neck remnant; four fusiform and two blister-like aneurysms were included in our series. SS were successfully implanted in all patients (100%). Misdeployment occurred in 17.6% of patients. In two of these patients adequate stent openness was achieved via Hyperglide balloon dilatation. Coil embolization in addition to SS placement was utilized in four aneurysms. One patient (3%) experienced transient morbidity due to a thromboembolic event and there was one mortality (3%) due to remote intraparenchymal haemorrhage. Complete occlusion of 27/33 (81.8 %) and 29/33 (87.9 %) aneurysms was achieved six and 12 months after the procedure, respectively. In-stent intimal hyperplasia was detected in 6.1 % patients. Flow-diverter Silk stent implantation is an effective method of treating complex aneurysms with acceptable mortality and morbidity rates. Complete occlusion is achieved in most of the complex aneurysms. PMID:25496683

  13. Management of giant intracranial ICA aneurysms with combined extracranial-intracranial anastomosis and endovascular occlusion.

    PubMed

    Serbinenko, F A; Filatov, J M; Spallone, A; Tchurilov, M V; Lazarev, V A

    1990-07-01

    Nine patients with giant internal carotid artery (ICA) aneurysms (greater than 2.5 cm in diameter) were subjected to a combined extracranial-intracranial (EC-IC) bypass procedure and endovascular ICA occlusion during 1987 and 1988. The procedures were performed under one anesthetic. In all cases the collateral circulation had been judged insufficient on the basis of a strict preoperative testing protocol including: cerebral panangiography, electroencephalography, somatosensory potential recording, and cerebral blood flow monitoring during manual compression of the ICA in the neck. There were four intracavernous ICA aneurysms, four carotid-ophthalmic artery aneurysms, and one supraclinoid ICA aneurysm. All patients showed symptoms and signs of compression of the surrounding nervous structures. In the five cases of intradural lesions, the artery was occluded at the level of the aneurysm neck, so the ophthalmic artery had to be occluded. There was, nevertheless, no case of worsening of vision following surgery, and all nine patients showed significant improvement following the combined procedure. A combined EC-IC bypass procedure and endovascular ICA occlusion allows for immediate verification of the surgical results and appears to be a worthwhile method for treating giant intracranial aneurysms.

  14. 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

  15. Laser Doppler anemometer measurements of pulsatile flow in a model carotid bifurcation.

    PubMed

    Ku, D N; Giddens, D P

    1987-01-01

    Hemodynamics at the human carotid bifurcation is important to the understanding of atherosclerotic plaque initiation and progression as well as to the diagnosis of clinically important disease. Laser Doppler anemometry was performed in a large scale model of an average human carotid. Pulsatile waveforms and physiologic flow divisions were incorporated. Disturbance levels and shear stresses were computed from ensemble averages of the velocity waveform measurements. Flow in the common carotid was laminar and symmetric. Flow patterns in the sinus, however, were complex and varied considerably during the cycle. Strong helical patterns and outer wall flow separation waxed and waned during each systole. The changing flow patterns resulted in an oscillatory shear stress at the outer wall ranging from -13 to 9 dyn cm-2 during systole with a time-averaged mean of only -0.5 dyn cm-2. This contrasts markedly with an inner wall shear stress range of 17-50, (mean 26) dyn cm-2. The region of transient separation was confined to the carotid sinus outer wall with no reverse velocities detected in the distal internal carotid. Notable disturbance velocities were also time-dependent, occurring only during the deceleration phase of systole and the beginning of diastole. The present pulsatile flow studies have aided in identifying hemodynamic conditions which correlate with early intimal thickening and predict the physiologic level of flow disturbances in the bulb of undiseased internal carotid arteries.

  16. [Carotid ultrasonography: evaluation of carotid ultrasonography].

    PubMed

    Taniuchi, Ryosui

    2007-02-01

    Carotid ultrasonography is a laboratory procedure showing how arteriosclerosis screening can diagnose carotid artery occlusion and high-grade stenosis. It is useful for inspection in general practice because of its non-invasiveness, development of sonography equipment, laboratory methods and the establishment of an evaluation method. We generally use a linear array probe of around 7-8MHz for carotid observation and combine the B mode method, color and power Doppler method, and pulsed Doppler method for inspection. At vessel analysis, the intima-media thickness, the property of plaque and stenotic ratio are evaluated. We observe the direction of bloodstream and presence of stricture by Doppler color flow imaging and measure flow velocity and the wave pattern by pulsed Doppler method and, with the B mode method, evaluate the extent or degree of stricture. This can be depicted well using a convex array probe and sector array probe when the mental change caused by disease is deep, and depiction is difficult by linear array probe.

  17. A dimensionless parameter for classifying hemodynamics in intracranial

    NASA Astrophysics Data System (ADS)

    Asgharzadeh, Hafez; Borazjani, Iman

    2015-11-01

    Rupture of an intracranial aneurysm (IA) is a disease with high rates of mortality. Given the risk associated with the aneurysm surgery, quantifying the likelihood of aneurysm rupture is essential. There are many risk factors that could be implicated in the rupture of an aneurysm. However, the most important factors correlated to the IA rupture are hemodynamic factors such as wall shear stress (WSS) and oscillatory shear index (OSI) which are affected by the IA flows. Here, we carry out three-dimensional high resolution simulations on representative IA models with simple geometries to test a dimensionless number (first proposed by Le et al., ASME J Biomech Eng, 2010), denoted as An number, to classify the flow mode. An number is defined as the ratio of the time takes the parent artery flow transports across the IA neck to the time required for vortex ring formation. Based on the definition, the flow mode is vortex if An>1 and it is cavity if An<1. We show that the specific definition of Le et al. works for sidewall but needs to be modified for bifurcation aneurysms. In addition, we show that this classification works on three-dimensional geometries reconstructed from three-dimensional rotational angiography of human subjects. Furthermore, we verify the correlation of IA flow mode and WSS/OSI on the human subject IA. This work was supported partly by the NIH grant R03EB014860, and the computational resources were partly provided by CCR at UB. We thank Prof. Hui Meng and Dr. Jianping Xiang for providing us the database of aneurysms and helpful discussions.

  18. 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

  19. Palmar artery aneurysm

    PubMed Central

    Shutze, Ryan A.; Liechty, Joseph

    2017-01-01

    Aneurysms of the hand are rarely encountered and more rarely reported. The least common locations of these aneurysms are the palmar and digital arteries. The etiologies of these entities are quite varied, although they usually present as a pulsatile mass. Following a thorough evaluation, including arterial anatomic imaging, they should be repaired. The reported results following repair have been good. Herein we report a girl with a spontaneous palmar artery aneurysm and its management. PMID:28127131

  20. Vein of Galen Aneurysms

    PubMed Central

    Komiyama, M.; Nakajima, H.; Nishikawa, M.; Yamanaka, K.; Iwai, Y.; Yasui, T.; Morikawa, T.; Kitano, S.; Sakamoto, H.; Nishio, A.

    2001-01-01

    Summary Eleven patients with so-called “vein of Galen aneurysms ” are reported, six of whom presented with vein of Galen aneurysmal malformations (four with choroidal type and two with mural type malformations). The remaining five patients presented with vein of Galen aneurysmal dilatations secondarily due to an arteriovenous malformation in one patient, an arteriovenous fistula in another, dural arteriovenous fistulas in two patients, and a varix in another. Treatments for these patients were individualised with consideration given to the clinical manifestations and the angioarchitecture of their lesions. Endovascular intervention played a critical role in the treatment of these vein of Galen aneurysms. PMID:20663385

  1. Microguidewire Looping to Traverse Stented Parent Arteries of Intracranial Aneurysms

    PubMed Central

    Cho, Young Dae; Rhim, Jong Kook; Yoo, Dong Hyun; Kang, Hyun-Seung; Kim, Jeong Eun; Han, Moon Hee

    2017-01-01

    Objective Stents are widely used in coil embolization of intracranial aneurysms, but on occasion, a microcatheter must traverse a stented segment of artery (so-called trans-cell technique) to select an aneurysm, or double stenting may necessary. In such situations, microguidewire passage and microcatheter delivery through a tortuous stented parent artery may pose a technical challenge. Described herein is a microguidewire looping technique to facilitate endovascular navigation in these circumstances. Methods To apply this technique, the microguidewire tip is looped before entering the stented parent artery and then advanced distally past the stented segment, with the loop intact. Rounding of the tip prevents interference from stent struts during passage. A microcatheter is subsequently passed into the stented artery for positioning near the neck of aneurysm, with microguidewire assistance. The aneurysm is then selected, steering the microcatheter tip (via inner microguidewire) into the dome. Results This technique proved successful during coil embolization of nine saccular intracranial aneurysms (internal carotid artery [ICA], 6; middle cerebral artery, 2; basilar tip, 1), performing eight trans-cell deliveries and one additional stenting. Selective endovascular embolization was enabled in all patients, resulting in excellent clinical and radiologic outcomes, with no morbidity or mortality directly attributable to microguidewire looping. Conclusion Microguidewire looping is a reasonable alternative if passage through a stented artery is not feasible by traditional means, especially at paraclinoid ICA sites. PMID:28264249

  2. Operative treatment of aneurysms and Coanda effect: a working hypothesis.

    PubMed

    Robinson, J L; Roberts, A

    1972-12-01

    The Coanda effect has been known to mechanical engineers for many decades. Consideration of this effect both by a neurosurgeon and a mechanical engineer revealed that it might be of importance during the operative treatment of intracranial aneurysms. If a jet effect were produced in the stream of blood after clipping an aneurysm, most of the flow of blood might be directed down only one limb of a bifurcation occurring in a vessel near to a clipped aneurysm. Blood might also be entrained from the other limb of the bifurcation. This boundary wall effect, which can occur without the rate of flow through the vessel being altered appreciably, could explain some of the unfortunate sequelae of aneurysm surgery which occur in the absence of any obvious cause such as postoperative thrombosis, etc. A possible mechanism for some of the complications after gradual occlusion of the common carotid artery in the neck is also proposed on this basis. Other details of how this data might be of clinical significance, together with suggestions for how to avoid fluidic effects during aneurysm surgery, are presented.

  3. “True” posterior communicating aneurysms: Three cases, three strategies

    PubMed Central

    Nery, Breno; Araujo, Ricardo; Burjaili, Bruno; Smith, Timothy R.; Rodrigues, Jose Carlos; Silva, Marcelo Nery

    2016-01-01

    Background: The authors provide a review of true aneurysms of the posterior communicating artery (PCoA). Three cases admitted in our hospital are presented and discussed as follows. Case Descriptions: First patient is a 51-year-old female presenting with a Fisher II, Hunt-Hess III (headache and confusion) subarachnoid hemorrhage (SAH) from a ruptured true aneurysm of the right PCoA. She underwent a successful ipsilateral pterional craniotomy for aneurysm clipping and was discharged on postoperative day 4 without neurological deficit. Second patient is a 53-year-old female with a Fisher I, Hunt-Hess III (headache, mild hemiparesis) SAH and multiple aneurisms, one from left ophthalmic carotid artery and one (true) from right PCoA. These lesions were approached and successfully treated by a single pterional craniotomy on the left side. The patient was discharged 4 days after surgery, with complete recovery of muscle strength during follow-up. Third patient is a 69-year-old male with a Fisher III, Hunt-Hess III (headache and confusion) SAH, from a true PCoA on the right. He had a left subclavian artery occlusion with flow theft from the right vertebral artery to the left vertebral artery. The patient underwent endovascular treatment with angioplasty and stent placement on the left subclavian artery that resulted in aneurysm occlusion. Conclusion: In conclusion, despite their seldom occurrence, true PCoA aneurysms can be successfully treated with different strategies. PMID:26862441

  4. The effects of hemodynamic lag on functional connectivity and behavior after stroke.

    PubMed

    Siegel, Joshua S; Snyder, Abraham Z; Ramsey, Lenny; Shulman, Gordon L; Corbetta, Maurizio

    2016-12-01

    Stroke disrupts the brain's vascular supply, not only within but also outside areas of infarction. We investigated temporal delays (lag) in resting state functional magnetic resonance imaging signals in 130 stroke patients scanned two weeks, three months and 12 months post stroke onset. Thirty controls were scanned twice at an interval of three months. Hemodynamic lag was determined using cross-correlation with the global gray matter signal. Behavioral performance in multiple domains was assessed in all patients. Regional cerebral blood flow and carotid patency were assessed in subsets of the cohort using arterial spin labeling and carotid Doppler ultrasonography. Significant hemodynamic lag was observed in 30% of stroke patients sub-acutely. Approximately 10% of patients showed lag at one-year post-stroke. Hemodynamic lag corresponded to gross aberrancy in functional connectivity measures, performance deficits in multiple domains and local and global perfusion deficits. Correcting for lag partially normalized abnormalities in measured functional connectivity. Yet post-stroke FC-behavior relationships in the motor and attention systems persisted even after hemodynamic delays were corrected. Resting state fMRI can reliably identify areas of hemodynamic delay following stroke. Our data reveal that hemodynamic delay is common sub-acutely, alters functional connectivity, and may be of clinical importance.

  5. Fluid-structure Interaction Modeling of Aneurysmal Conditions with High and Normal Blood Pressures

    NASA Astrophysics Data System (ADS)

    Torii, Ryo; Oshima, Marie; Kobayashi, Toshio; Takagi, Kiyoshi; Tezduyar, Tayfun E.

    2006-09-01

    Hemodynamic factors like the wall shear stress play an important role in cardiovascular diseases. To investigate the influence of hemodynamic factors in blood vessels, the authors have developed a numerical fluid-structure interaction (FSI) analysis technique. The objective is to use numerical simulation as an effective tool to predict phenomena in a living human body. We applied the technique to a patient-specific arterial model, and with that we showed the effect of wall deformation on the WSS distribution. In this paper, we compute the interaction between the blood flow and the arterial wall for a patient-specific cerebral aneurysm with various hemodynamic conditions, such as hypertension. We particularly focus on the effects of hypertensive blood pressure on the interaction and the WSS, because hypertension is reported to be a risk factor in rupture of aneurysms. We also aim to show the possibility of FSI computations with hemodynamic conditions representing those risk factors in cardiovascular disease. The simulations show that the transient behavior of the interaction under hypertensive blood pressure is significantly different from the interaction under normal blood pressure. The transient behavior of the blood-flow velocity, and the resulting WSS and the mechanical stress in the aneurysmal wall, are significantly affected by hypertension. The results imply that hypertension affects the growth of an aneurysm and the damage in arterial tissues.

  6. Bronchial Aneurysms Mimicking Aortic Aneurysms: Endovascular Treatment in Two Patients

    SciTech Connect

    Vernhet, Helene; Bousquet, Claudine; Jean, Betty; Lesnik, Alvian; Durand, Gerard; Giron, Jacques; Senac, Jean Paul

    1999-05-15

    Bronchial artery dilatation and aneurysm formation is a potential complication of local inflammation, especially in bronchiectasis. When the bronchial artery has an ectopic origin from the inferior segment of the aortic arch, aneurysms may mimick aortic aneurysms. Despite this particular location, endovascular treatment is possible. We report two such aneurysms that were successfully embolized with steel coils.

  7. Screening for Carotid Artery Stenosis

    MedlinePlus

    ... Task Force learned about the potential benefits and harms of screening for carotid artery stenosis: Health professionals ... blood flow through the arteries. Potential Benefits and Harms of Carotid Artery Stenosis Screening and Treatment The ...

  8. Endoscope-assisted clipping of a superior hypophyseal artery aneurysm without removal of the anterior clinoid process. Case report.

    PubMed

    Kinouchi, Hiroyuki; Futawatari, Katsuya; Mizoi, Kazuo; Higashiyama, Naoki; Kojima, Hisashi; Sakamoto, Tetsuya

    2002-04-01

    A 47-year-old man presented with a superior hypophyseal artery aneurysm and an ipsilateral posterior communicating artery aneurysm. Both lesions were successfully clipped without removal of the anterior clinoid process or retraction of the optic nerve by using endoscopic guidance. The endoscope was introduced into the prechiasmatic cistern and provided a clear visual field around the aneurysm that could not be seen via the operating microscope. The endoscope was useful in the identification of the medially projecting lesion and the small perforating branches of the ophthalmic segment of the internal carotid artery. A fenestrated clip could be introduced around the neck of the aneurysm and placed in the best position under endoscopic guidance. Endoscopy-assisted clipping is potentially a very useful procedure for aneurysm surgery.

  9. Endovascular Stent Grafting for Aortic Arch Aneurysm in Aortoiliac Occlusive Disease following Aortic Arch Debranching and Aortobifemoral Reconstruction

    PubMed Central

    Canbay, Cagla; Onal, Yilmaz; Beyaz, Metin Onur; Sayin, Omer Ali; Barburoglu, Mehmet; Yornuk, Mesut; Acunas, Bulent; Alpagut, Ufuk; Dayioglu, Enver

    2017-01-01

    Treatment of thoracic aortic aneurysms constitutes high mortality and morbidity rates despite improvements in surgery, anesthesia, and technology. Endovascular stent grafting may be an alternative therapy with lower risks when compared with conventional techniques. However, sometimes the branches of the aortic arch may require transport to the proximal segments prior to successful thoracic aortic endovascular stent grafting. Atherosclerosis is accounted among the etiology of both aneurysms and occlusive diseases that can coexist in the same patient. In these situations stent grafting may even be more complicated. In this report, we present the treatment of a 92-year-old patient with aortic arch aneurysm and proximal descending aortic aneurysm. For successful thoracic endovascular stent grafting, the patient needed an alternative route other than the native femoral and iliac arteries for the deployment of the stent graft. In addition, debranching of left carotid and subclavian arteries from the aortic arch was also required for successful exclusion of the thoracic aneurysm.

  10. Accessory left gastric artery aneurysms in granulomatosis with polyangiitis: a case report and literature review

    PubMed Central

    Tomosugi,, Toshihide; Takahashi, Takuji; Kawase, Yoshihisa; Yoshida, Koichi; Hayashi, Shogo; Sugiyama, Takefumi; Shimizu, Mitsuya; Shoka, Michita; Sawaki, Kohichi; Onishi, Eiji; Hayashi, Naomi; Matsushita, Hidenobu; Okochi, Osamu

    2017-01-01

    ABSTRACT Aneurysm formation is a potential complication of granulomatosis with polyangiitis (GPA), previously known as Wegener’s granulomatosis. It is a very rare complication, but immediate diagnosis and therapy should be performed because an aneurysm can be life-threatening if it ruptures. An accessory left gastric artery (ALGA) is also a rare variant gastric artery that may obtain its blood supply from the left hepatic artery and left gastric artery. We herein describe a 57-year-old Japanese man who was diagnosed with GPA complicated by aneurysm rupture in an ALGA. Emergency surgery was performed after failure of arterial coil embolization to interrupt blood flow in the ALGA. The patient underwent partial resection of the lesser omentum, which contained all aneurysms. During partial resection of the lesser omentum, both the left gastric artery and ALGA were ligated because they were thought to be feeders of the aneurysms. Postoperative recovery was uneventful; no bleeding or recurrence of the aneurysms occurred. Immediate diagnosis and therapy should be performed for patients with GPA with symptoms of vascular ischemia or aortitis. Endovascular intervention is the first-choice therapy especially for hemodynamically stable patients with ruptured aneurysms or aneurysms located on variant arteries, which may have multiple blood supplies. In the present case, although endovascular treatment failed, the approach described herein was helpful during open surgery. PMID:28303064

  11. Treatment Challenges of a Primary Vertebral Artery Aneurysm Causing Recurrent Ischemic Strokes

    PubMed Central

    Peruzzotti-Jametti, Luca; Fanelli, Giovanna; Simionato, Franco; Chiesa, Roberto; Rinaldi, Enrico; Comi, Giancarlo; Sessa, Maria

    2017-01-01

    Background. Extracranial vertebral artery aneurysms are a rare cause of embolic stroke; surgical and endovascular therapy options are debated and long-term complication may occur. Case Report. A 53-year-old man affected by neurofibromatosis type 1 (NF1) came to our attention for recurrent vertebrobasilar embolic strokes, caused by a primary giant, partially thrombosed, fusiform aneurysm of the left extracranial vertebral artery. The aneurysm was treated by endovascular approach through deposition of Guglielmi Detachable Coils in the proximal segment of the left vertebral artery. Six years later the patient presented stroke recurrence. Cerebral angiography and Color Doppler Ultrasound well characterized the unique hemodynamic condition developed over the years responsible for the new embolic event: the aneurysm had been revascularized from its distal portion by reverse blood flow coming from the patent vertebrobasilar axis. A biphasic Doppler signal in the left vertebral artery revealed a peculiar behavior of the blood flow, alternately directed to the aneurysm and backwards to the basilar artery. Surgical ligation of the distal left vertebral artery and excision of the aneurysm were thus performed. Conclusion. This is the first described case of NF1-associated extracranial vertebral artery aneurysm presenting with recurrent embolic stroke. Complete exclusion of the aneurysm from the blood circulation is advisable to achieve full resolution of the embolic source. PMID:28168068

  12. Current status of computational fluid dynamics for cerebral aneurysms: the clinician's perspective.

    PubMed

    Wong, George K C; Poon, W S

    2011-10-01

    The ultimate management goal for unruptured intracranial aneurysms is to select the aneurysms at risk of rupture and treat them. Computational fluid dynamics (CFD) utilizes mechanical engineering principles to explicate what occurs in tubes (vessels) and bulges (aneurysms). CFD parameters have been related to the biological processes that occur in the aneurysm wall, and models have been developed to predict the risk of aneurysm rupture. A PubMed search from 1 January 1970 to 30 November 2010 was carried out using the keywords "computational fluid dynamics" AND "cerebral aneurysm". References were also reviewed for relevant articles. All relevant articles were then reviewed by a vascular neurosurgeon, who found that the hemodynamic parameters of wall shear stress (WSS), WSS gradient, inflow jet, impingement zone, and aneurysm inflow-angle (IA) lack the predictive values required for clinical practice. CFD study can now be simulated and reproduced in a simple and fast analysis of steady, non-pulsatile flow with phase contrast magnetic resonance-derived volumetric inflow rate but the key question of whether a patient-specific CFD model can predict the rupture risk of unruptured intracranial aneurysms remains to be determined in future studies incorporating multivariate analysis. CFD models will become available for routine clinical practice as the computational power of computers further improves.

  13. [Grafting of carotid arteries].

    PubMed

    Belov, Iu V; Stepanenko, A B; Gens, A P; Bazylev, V V; Seleznev, M N; Savichev, D D

    2005-01-01

    Over 5-years, 167 reconstructive surgeries for stenosis of internal carotid arteries (ICA) were performed in 124 patients. Mean age of the patients was 63.5 years. One hundred and twenty-nine carotid endarterectomies (CEAE) in 86 patients and 38 reconstructive operations of ICA in 38 patients were performed. There were no lethal outcomes in short- and long-term postoperative period. In short-term period after prosthesis of ICA restenosis was revealed in 3% patients, after eversion CEAE in 3% patients the embolism was seen, after standard CEAE restenosis were diagnosed in 8% patients and thrombosis -- in 3%. In long-term period after grafting of ICA the strokes were seen in 3%, stenosis -- in 6% patients, after eversion endarterectomy -- in 0 and 3% patients, and after standard CEAE -- in 3 and 24% patients, respectively. It is concluded that grafting of ICA is adequate surgical method of reconstruction and stroke prevention in specific variants of carotid atherosclerosis.

  14. Flow changes due to placing multiple stents across the neck of sidewall and bifurcating aneurysms

    NASA Astrophysics Data System (ADS)

    Cantón, Gádor; Lasheras, Juan C.; Levy, David I.

    2004-11-01

    The last fifteen years have seen the development of new materials and devices for the treatment of cerebral aneurysms via an endovascular approach. In this study we aim to investigate, from the hemodynamical point of view, the effect of the deployment of multiple Neuroform stents (without the use of any coils or other packing agents) in the flow inside the aneurysmal sac. Although there are reports concerning the favorable clinical output after using this new technique, there is not a complete quantitative study of the changes in the flow and hemodynamic forces inside the aneurysmal pouch resulting from the placement of multiple stents across its neck. For this purpose, a Digital Particle Image Velocimetry (DPIV) technique is used to measure the pulsatile blood velocity field at the entrance and inside the sac of silicone models of sidewall and bifurcating aneurysms with prototypical shapes. Measurements of the circulation inside the sac show that the use of multiple flexible intravascular stents can effectively reduce the strength of the vortex forming inside the aneurysmal sac with subsequent decrease in the magnitude of the shear stresses acting on the aneurysmal wall.

  15. Treatment of Giant Intracranial Aneurysms

    PubMed Central

    Lv, X.; Jiang, C.; Li, Y.; Yang, X.; Zhang, J.; Wu, Z.

    2009-01-01

    Summary We report on report the clinical outcome obtained in treatment of giant intracranial aneurysms (GAs). Between 2005 and 2007, 51 patients with 51 GAs presented at our hospital. Twentynine were treated with primary parent vessel occlusion without distal bypass and ten underwent treatment preserving the parent artery. Twelve patients could not be treated endovascularly. Selective embolization (including two remodeling techniques and two stent-coil embolizations) resulted in only one cure. Two patients died as a result of subarachnoid hemorrhage periprocedurely. Twenty-nine patients treated primarily with parent vessel occlusion and three patients treated with covered stent were considered cured after their treatments. Only one patient treated with parent vessel occlusion experienced ischemia during follow-up, which resulted in a mild neurological deficit. Of the twelve patients who could not be treated endovascularly, one succumbed to surgery, four died while being treated conservatively, and three were lost to follow-up. Parent artery occlusion, covered stent and coil occlusion provide effective protection against bleeding. In treatment of paraclinoid GAs of the internal carotid artery, the use of a stent, and stent-assisted coil embolization may be a pitfall. PMID:20465907

  16. MR and CT diagnosis of carotid pseudoaneurysm in children following surgical resection of craniopharyngioma.

    PubMed

    Lakhanpal, S K; Glasier, C M; James, C A; Angtuaco, E J

    1995-01-01

    We report the cases of two children who underwent CT, MR, MRA and angiography in the diagnosis of postoperative aneurysmal dilatation of the supraclinoid carotid arteries following surgical resection of craniopharyngioma. Craniopharyngiomas are relatively common lesions, accounting for 6-7% of brain tumors in children. They are histologically benign, causing symptoms by their growth within the sella and suprasellar cistern with compression of adjacent structures, especially the pituitary gland, hypothalamus and optic nerves, chiasm, and tracts. Complete surgical resection, particularly of large tumors, is complicated by the fact that the lesions are usually found within the circle of Willis, with displacement and adherence to the adventitia of these vessels [1, 2]. Recent reports in the neurosurgical literature have described aneurysmal dilatation of the supraclinoid internal carotid arteries following aggressive surgical resection of craniopharyngioma [3, 4].

  17. Kinking of internal carotid artery: is it a risk factor for cerebro-vascular damage in patients undergoing cardiac surgery?

    PubMed

    Borioni, R; Garofalo, M; Actis Dato, G M; Pierri, M D; Caprara, E; Albano, P; Chiariello, L

    1994-08-01

    The incidence of carotid artery kinking is reported from 4% to 25% in different studies. During cardiopulmonary by-pass (CPB) in cardiac surgery the hemodynamic effects related to the kinking could produce hypoperfusion especially if associated with atherosclerotic lesions of the carotid arteries. We report our experience of 653 patients (538 males, 115 females, mean age 58.3 years) studied by coronaroangiography and internal carotid artery duplex scanning during the period January 1991-December 1992. Thirty-seven patients (22 males, 15 females, mean age 64.9 years), revealed anomalies of the internal carotid artery classificated as tortuosity (9 patients; 24.4%), and kinking (28 patients; 75.6%). All but 4 patients underwent cardiac surgery isolated or associated with carotid thrombo-endarterectomy (TEA) with Dacron patch arterioplasty. Three patients died (8.1%), one of them from cerebrovascular accident. He was a patient who had thromboembolism from the ascending aorta but without associated atherosclerotic lesions of carotid arteries. Asymptomatic isolated internal carotid artery kinking does not seem to be a risk factor for neurological complications during CPB. If carotid kinking is symptomatic and associated with atherosclerotic plaque producing internal carotid artery stenosis greater than 75%, we strongly suggest surgical treatment before cardiac operation.

  18. Embolization of Brain Aneurysms and Fistulas

    MedlinePlus

    ... Resources Professions Site Index A-Z Embolization of Brain Aneurysms and Arteriovenous Malformations/Fistulas Embolization of brain ... Brain Aneurysms and Fistulas? What is Embolization of Brain Aneurysms and Fistulas? Embolization of brain aneurysms and ...

  19. Ruptured Pancreaticoduodenal Artery Aneurysm Associated with Median Arcuate Ligament Compression and Aortic Dissection Successfully Treated with Embolotherapy

    PubMed Central

    Terada, Takuro; Tamaki, Masato

    2015-01-01

    A 51-year-old man with a ruptured pancreaticoduodenal artery (PDA) aneurysm caused by compression of the celiac artery by the median arcuate ligament and aortic dissection involving the celiac axis was transferred to our hospital for endovascular treatment. A 4-F catheter was advanced into the superior mesenteric artery through the narrow true lumen via the left brachial artery, and coil embolization of the aneurysm was successfully performed. In this case, rapid increase of blood flow in the superior mesenteric artery, which compensated for the decreased celiac blood flow by aortic dissection, increased hemodynamic stress on the PDA, leading to aneurysmal rupture. PMID:25848431

  20. [Ruptured sinus of Valsalva aneurysm and pregnancy: what anesthetic technique should be preferred for a scheduled cesarean section?].

    PubMed

    Peláez Romero, R; Grigorov, I; Giménez, I; Aguilar, J L; Atanassoff, P

    2010-03-01

    Sinus of Valsalva aneurysm is a rare cardiac abnormality rupture the right sinus and if ruptured open into the right ventricle or atrium. Usually silent, may cause significant hemodynamic changes. Few cases of ruptured Valsalva sinus aneurysm have been reported in the literature, and the course of this condition during pregnancy and anesthetic management have scarcely been mentioned. We report the case of a primipara with a Valsalva sinus aneurysm that ruptured into the right ventricle. Cardiac function worsened as pregnancy progressed. A cesarean section under spinal anesthesia was scheduled.

  1. Evaluation of an asymmetric stent patch design for a patient specific intracranial aneurysm using computational fluid dynamic (CFD) calculations in the computed tomography (CT) derived lumen

    NASA Astrophysics Data System (ADS)

    Kim, Minsuok; Ionita, Ciprian; Tranquebar, Rekha; Hoffmann, Kenneth R.; Taulbee, Dale B.; Meng, Hui; Rudin, Stephen

    2006-03-01

    Stenting may provide a new, less invasive therapeutic option for cerebral aneurysms. However, a conventional porous stent may be insufficient in modifying the blood flow for clinical aneurysms. We designed an asymmetric stent consisting of a low porosity patch welded onto a porous stent for an anterior cerebral artery aneurysm of a specific patient geometry to block the strong inflow jet. To evaluate the effect of the patch on aneurysmal flow dynamics, we "virtually" implanted it into the patient's aneurysm geometry and performed Computational Fluid Dynamics (CFD) analysis. The patch was computationally deformed to fit into the vessel lumen segmented from the patient CT reconstructions. After the flow calculations, a patch with the same design was fabricated using laser cutting techniques and welded onto a commercial porous stent, creating a patient-specific asymmetric stent. This stent was implanted into a phantom, which was imaged with X-ray angiography. The hemodynamics of untreated and stented aneurysms were compared both computationally and experimentally. It was found from CFD of the patient aneurysm that the asymmetric stent effectively blocked the strong inflow jet into the aneurysm and eliminated the flow impingement on the aneurysm wall at the dome. The impact zone with elevated wall shear stress was eliminated, the aneurysmal flow activity was substantially reduced, and the flow was considerably reduced. Experimental observations corresponded well qualitatively with the CFD results. The demonstrated asymmetric stent could lead to a new minimally invasive image guided intervention to reduce aneurysm growth and rupture.

  2. Carotid Artery Screening

    MedlinePlus

    ... or radiologist then places the transducer on the skin in various locations, sweeping over the area of interest or angling the sound beam from a different location to better see an area of concern. Doppler sonography and Carotid IMT US are performed using the ...

  3. [Syncope and carotid paraganglioma].

    PubMed

    Bizueto-Rosas, Héctor; Salazar-Reyes, Anabel; Moran-Reyes, Ely Guadalupe; González-Arcos, Gregorio; Hernández-Pérez, Noemí A; Solorio-Rosette, Hugo F; Soto-Hernández, Gabriel

    2014-01-01

    Syncope is a medical emergency, which is more or less frequent. Its prevalence increases with age. It is defined as the loss of consciousness and postural tone resulting from a transient alteration of cerebral flow. It appears suddenly, but it does not leave behind any sequela or after-effects. Out of two groups, the neutrally mediated (or neuromediated) syncope, especially the one called carotid sinus hypersensitivity, is related to the carotid sinus paraganglioma. It is triggered by sinus pressure, which results in sudden death by overstimulation. In the next article, we show the case of a sexagenarian female patient with a disabling syncope and a 7 cm carotid body paraganglioma, which did not allow her the minimum movement of lateral dorsiflexion or extension of the neck. For this reason, the patient had to remain hospitalized, in a dorsal decubitus position with semiflexion of the neck. Before the surgery was practiced, a temporary pacemaker was used, and after the resection of the carotid body paraganglioma, in accordance to the patient's studies of cardiac electrophysiology, she was discharged without electrical nerve stimulation.

  4. Carotid artery surgery

    MedlinePlus

    ... may help lower your chance of having a stroke. But you will need to make lifestyle changes to help prevent plaque buildup, blood clots, and other problems in your carotid arteries over time. You may need to change your diet and start an exercise program, if your doctor tells you exercise is ...

  5. 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

  6. Computational modeling of flow-altering surgeries in basilar aneurysms.

    PubMed

    Rayz, V L; Abla, A; Boussel, L; Leach, J R; Acevedo-Bolton, G; Saloner, D; Lawton, M T

    2015-05-01

    In cases where surgeons consider different interventional options for flow alterations in the setting of pathological basilar artery hemodynamics, a virtual model demonstrating the flow fields resulting from each of these options can assist in making clinical decisions. In this study, image-based computational fluid dynamics (CFD) models were used to simulate the flow in four basilar artery aneurysms in order to evaluate postoperative hemodynamics that would result from flow-altering interventions. Patient-specific geometries were constructed using MR angiography and velocimetry data. CFD simulations carried out for the preoperative flow conditions were compared to in vivo phase-contrast MRI measurements (4D Flow MRI) acquired prior to the interventions. The models were then modified according to the procedures considered for each patient. Numerical simulations of the flow and virtual contrast transport were carried out in each case in order to assess postoperative flow fields and estimate the likelihood of intra-aneurysmal thrombus deposition following the procedures. Postoperative imaging data, when available, were used to validate computational predictions. In two cases, where the aneurysms involved vital pontine perforator arteries branching from the basilar artery, idealized geometries of these vessels were incorporated into the CFD models. The effect of interventions on the flow through the perforators was evaluated by simulating the transport of contrast in these vessels. The computational results were in close agreement with the MR imaging data. In some cases, CFD simulations could help determine which of the surgical options was likely to reduce the flow into the aneurysm while preserving the flow through the basilar trunk. The study demonstrated that image-based computational modeling can provide guidance to clinicians by indicating possible outcome complications and indicating expected success potential for ameliorating pathological aneurysmal flow

  7. Treatment of intracranial aneurysms using flow-diverting silk stents (BALT): a single centre experience.

    PubMed

    Leonardi, M; Cirillo, L; Toni, F; Dall'olio, M; Princiotta, C; Stafa, A; Simonetti, L; Agati, R

    2011-09-01

    The Silk stent (Balt, Montmorency, France) is a retractable device designed to achieve curative reconstruction of the parent artery associated with an intracranial aneurysm. We present our initial experience with the Silk flow-diverting stent in the management and follow-up of 25 patients presenting with intracranial aneurysms.Twenty-five patients (age range, 34-81 years; 24 female) were treated with the Silk flow-diverting device. Aneurysms ranged in size from small (5), large (10) and giant (10) and included wide-necked aneurysms, multiple, nonsaccular, and recurrent intracranial aneurysms. Nine aneurysms were treated for headache, 14 for mass effect. None presented with haemorrhage. All patients were pretreated with dual antiplatelet medications for at least 72 hours before surgery and continued taking both agents for at least three months after treatment. A total of 25 Silk stents were used. Control MR angiography and/or CT angiography was typically performed prior to discharge and at one, three, six and 12 months post treatment. A follow-up digital subtraction angiogram was performed between six and 19 months post treatment.Complete angiographic occlusion or subtotal occlusion was achieved in 15 patients in a time frame from three days to 12 months. Three deaths and one major complication were encountered during the study period. Two patients, all with cavernous giant aneurysms, experienced transient exacerbations of preexisting cranial neuropathies and headache after the Silk treatment. Both were treated with corticosteroids, and symptoms resolved completely within a month.In our experience the Silk stent has proven to be a valuable tool in the endovascular treatment of intracranial giant partially thrombosed aneurysms and aneurysms of the internal carotid artery cavernous segment presenting with mass effect. The time of complete occlusion of the aneurysms and the risk of the bleeding is currently not predictable.

  8. Evaluation of intracranial aneurysms with CT angiography: current status and future direction

    NASA Astrophysics Data System (ADS)

    Sato, Yutaka; Sickels, William; Quets, Jerome; Crosby, Daniel; Chang, Shereen; Cook-Granroth, Janice; Hoffman, Eric A.

    1997-05-01

    Purpose: To develop a valid, reliable and accurate system of measurement of intracranial aneurysm geometry using volumetric data obtained by CT angiography. Materials and methods: A simple model of lateral saccular aneurysm was created. Three models were prepared with different size of aneurysm sac and neck. Volumetric data was acquired using a Toshiba Xpress SX helical scanner. Geometry of an aneurysm model obtained by workstation linked to the scanner applying volume rendering display and dedicated UNIX based computer applying MPR based method. These results were compared with actual caliper measurements of the model. A clinical case of lateral aneurysm arising from the supraclinoid internal carotid artery was also studied. Results: Both the volume rendered image based method and MPR based method provided accurate geometric information of an aneurysm sac and its neck. Conclusions: Volume rendering technique requires editing by a well-informed operator and subjective, while the MPR based method is more objective and better suited for quantitative analysis. Using these mutually complimentary tools, critical geometric information of an aneurysm can be extracted from volumetric data provided by CTA.

  9. Endovascular treatment of recurrent intracranial aneurysms following previous microsurgical clipping with the Pipeline Embolization Device.

    PubMed

    Ding, Dale; Starke, Robert M; Evans, Avery J; Jensen, Mary E; Liu, Kenneth C

    2014-07-01

    The treatment of intracranial aneurysms with microsurgical clipping is associated with a very low rate of recurrence. However, in cases of aneurysm recurrence after previous clipping, microsurgical dissection due to adhesions and fibrosis may be challenging, and it may be difficult to safely occlude the recurrent lesion without the risk of significant morbidity. Flow-diverting stents have drastically changed the landscape of endovascular neurosurgery. We present two patients with large, recurrent supraclinoid internal carotid artery (ICA) aneurysms which were previously clipped 17 and 23 years ago at outside institutions. Both recurrent lesions were treated with the Pipeline Embolization Device (PED; ev3 Endovascular, Irvine, CA, USA) without radiographic or clinical complications. In the first patient, the 15 mm aneurysm significantly decreased in size at 6 month angiographic follow-up. The 21 mm aneurysm in the second patient was completely occluded 7 months following PED treatment. The moderate degree of in-stent stenosis present on initial follow-up imaging resolved on angiography 11 months post-treatment. The management of recurrent aneurysms after clipping is sparsely reported in the literature due to its infrequent occurrence. In carefully selected cases, flow-diverting stents may be used for complex aneurysms of the distal ICA, even for those which have recurred following microsurgical clipping.

  10. Intracranial aneurysms: Diagnostics accuracy of three-dimensional, fourier transform, time-of-flight MR angiography

    SciTech Connect

    Korogi, Yukunori; Takahashi, Mutsumasa; Mabuchi, Nobuhisa; Miki, Hitoshi; Fujiwara, Satoru; Horikawa, Yoshiharu; Nakagawa, Toshio; O`Uchi, Toshihiro; Watabe, Tsuneya; Shiga, Hayao

    1994-10-01

    To assess the accuracy of three-dimensional, Fourier transform, time-of-flight magnetic resonance (MR) angiography in the identification of intracranial aneurysms. MR angiograms of 126 patients (59 male and 67 female patients, aged 12-77 years) with various intracranial vascular lesions were evaluated. Seventy-eight aneurysms, including 60 less than 5 mm in diameter, in 61 patients were depicted at conventional angiography. Eight projection images, as well as one axial collapsed MR angiogram obtained with a maximum-intensity projection algorithm, were used for evaluation. Sensitivity for the five observers ranged from 58% to 68% (mean, 63%). Higher sensitivity was achieved for anterior communicating and middle cerebral artery aneurysms, while that for internal carotid artery aneurysms was poor. Sensitivities for small and medium aneurysms ranged from 50% to 60% (mean, 56%) and from 77% to 94% (mean, 85%), respectively. MR angiography can depict intracranial aneurysms 5 mm or larger with good accuracy but is less useful for the identification of smaller aneurysms. 12 refs., 5 figs., 5 tabs.

  11. Inflammatory abdominal aortic aneurysm.

    PubMed

    Savarese, R P; Rosenfeld, J C; DeLaurentis, D A

    1986-05-01

    Between January 1976 and December 1982, 181 patients with abdominal aortic aneurysms were treated surgically, and in 13 patients the aneurysms were found to be inflammatory. Inflammatory aneurysms of the abdominal aorta (IAAA) share important characteristics with typical atherosclerotic abdominal aortic aneurysms. Diagnosis and surgical management of IAAA are distinctive which suggests that IAAA should be considered separately, as a varient of typical abdominal aortic aneurysms. IAAA occur predominantly in males. The presenting symptoms are often idiosyncratic and include severe abdominal or back pain, or both, and ureteral obstruction; the diagnosis of IAAA should be considered when these symptoms are present. Although grossly and microscopically, the perianeurysmal fibrosis resembles idiopathic retroperitoneal fibrosis, the two conditions can be differentiated. At the present time, ultrasonography and computed tomography appear to offer reliable means for diagnosing IAAA. The presence of IAAA, whether established preoperatively or discovered unexpectedly at operation, necessitate certain modifications in the surgical approach, in order to avoid injuring the duodenum and the venous structures. Most patients can be successfully treated by resection and graft replacement. Rupture of the aneurysm in IAAA appears to be less frequent than in typical atherosclerotic abdominal aortic aneurysm.

  12. Flow diverters for treatment of intracranial aneurysms: current status and ongoing clinical trials.

    PubMed

    Wong, George K C; Kwan, Marco C L; Ng, Rebecca Y T; Yu, Simon C H; Poon, W S

    2011-06-01

    The ultimate treatment goal for intracranial aneurysms is to reconstruct the vessel wall and correct the hemodynamic disturbance. A flow diverter is a stent placed in the parent artery to reduce blood flow in the aneurysm sac to the point of stagnation, gradual thrombosis, and neointimal remodeling to maintain outflow in the side branches and perforators. Here, we review the two commercially available flow diverters, the Pipeline Embolization Device (PED) and the SILK flow diverter (SFD). The rates of severe hemorrhagic complications have been reported to be 2% for the PED and 0.8% for the SFD. The results of studies completed thus far show that endovascular reconstruction with flow diverters is an effective treatment of wide-necked, fusiform, large, and giant unruptured intracranial aneurysms, with 5% to 10% of patients experiencing permanent major morbidity and mortality. The results of ongoing studies may resolve whether flow diverters can replace coil embolization for the treatment of all, or selected, intracranial aneurysms.

  13. Renal artery aneurysms.

    PubMed

    González, J; Esteban, M; Andrés, G; Linares, E; Martínez-Salamanca, J I

    2014-01-01

    A renal artery aneurysm is defined as a dilated segment of renal artery that exceeds twice the diameter of a normal renal artery. Although rare, the diagnosis and incidence of this entity have been steadily increasing due to the routine use of cross-sectional imaging. In certain cases, renal artery aneurysms may be clinically important and potentially lethal. However, knowledge of their occurrence, their natural history, and their prognosis with or without treatment is still limited. This article aims to review the recent literature concerning renal artery aneurysms, with special consideration given to physiopathology, indications for treatment, different technical options, post-procedure complications and treatment outcomes.

  14. Pediatric cerebral aneurysms.

    PubMed

    Gemmete, Joseph J; Toma, Ahmed K; Davagnanam, Indran; Robertson, Fergus; Brew, Stefan

    2013-11-01

    Childhood intracranial aneurysms differ from those in the adult population in incidence and gender prevalence, cause, location, and clinical presentation. Endovascular treatment of pediatric aneurysms is the suggested approach because it offers both reconstructive and deconstructive techniques and a better clinical outcome compared with surgery; however, the long-term durability of endovascular treatment is still questionable, therefore long-term clinical and imaging follow-up is necessary. The clinical presentation, diagnosis, and treatment of intracranial aneurysms in children are discussed, and data from endovascular treatments are presented.

  15. [Pharyngeal hemorrhaging due to iatrogenic false aneurysm. Complication after cannulation of the internal jugular vein].

    PubMed

    Kreckel, V; Langwara, H

    2009-03-01

    Catheterization of the internal jugular vein is used for temporary access to the central vein in patients with acute or chronic renal failure. The most frequent problem is the arterial puncture and accidental placement of the large catheter in an artery. This case report describes a rare secondary complication by accidental catheterization of the right common carotid artery after intended dual lumen catheter insertion into the right internal jugular vein. A false aneurysm with pharyngeal hemorrhaging developed 2 weeks after the puncture. The diagnosis was made using colour-Doppler ultrasound and the aneurysm was treated with vascular surgery.

  16. Modeling of cerebral aneurysm using equivalent electrical circuit (Lumped Model).

    PubMed

    Abdi, M; Karimi, A; Navidbakhsh, M; Hassani, K; Faghihi, S

    2014-03-01

    The circle of Willis (CoW) is a key asset in brain performance as it supports adequate blood supply to the brain. The lumped method (electrical equivalent circuits) is a useful model to simulate the process of the human cardiovascular system. In this study, the whole cardiovascular system is modeled, using an equivalent electrical circuit to investigate an aneurysm in an artery. The cerebrovascular system consists of 29 compartments, which includes the CoW. Each vessel is modeled by a resistor, a capacitor and an inductor. Using MATLAB Simulink, the left and right ventricles are modeled by controlled voltage sources and diodes. The effects of the left internal carotid artery aneurysm (Fusiform) on the pressure of the efferent arteries in the circle of Willis are studied. The modeling results are entirely in agreement with the available clinical observations. The results of the present study may have clinical implications for modeling different cardiovascular diseases, such as arterial stiffness and atherosclerosis.

  17. [Surgical prevention of stroke in patients with carotid stenosis].

    PubMed

    Pyshkina, L I; Khatagova, D T; Kabanov, A A; Darvish, N A; Alibekova, Zh M

    2014-01-01

    Objectives. To study the cerebral and central hemodynamics in patients with stenotic lesions of inner carotid arteries (ICA) before and after reconstructive surgery. Material and methods. Fifty-nine patients, aged from 46 to 78 years, with >50% atherosclerotic stenosis of ICA who underwent preventive carotid endarterectomy (CEAE) were examined. The isolate stenosis of ICA was identified in 13.6% of patients, concomitant lesions of brachiocephalic arteries in 86.4%. Atherosclerotic lesions of coronary arteries were found in 91.1% of patients and those of arteries of lower extremities in 45.8%. In 25.5% of patients, the heart surgery was performed before the current hospitalization. Heterogeneous atherosclerotic plaques with dense or hyperdense components were more frequents in symptomatic stenosis (63.3%). The maximal stenosis was identified in heterogeneous hyperechogenic plaques, the minimal ones in homogenous hypoechogenic plaques. Parameters of central hemodynamics were better in patients with 2nd stage of reconstructive surgeries. The emission fraction decreased proportionally to the degree of stenosis. The parameters of cerebral hemodynamics were significantly decreased in ICA stenosis and improved in the early post-surgery period. Results. CEAE promoted the improvement of cognitive functions and the recovery of motor functions. The best positive dynamics was recorded in asymptomatic ICA stenosis. Poor outcome (transitory ischemic attacks, urgent surgery, restenosis) was found in patients with low levels of central and cerebral hemodynamics 12-24 months after the discharge. Moreover, smoking and the degree of stenosis predicted poor outcome. Conclusions. Surgical treatment in combination with the complex pharmacotherapy (hypotensive drugs, antiaggregants and statins) had the maximal effect, including the remote period.

  18. Treatment of complex intracranial aneurysms using flow-diverting silk® stents. An analysis of 32 consecutive patients.

    PubMed

    Buyukkaya, Ramazan; Kocaeli, Hasan; Yildirim, Nalan; Cebeci, Hakan; Erdogan, Cüneyt; Hakyemez, Bahattin

    2014-12-01

    This study describes the peri-procedural and late complications and angiographic follow-up results of 32 patients with 34 complex aneurysms treated with flow diverter Silk stents in a single centre. In this retrospective study, 40 Silk stents (SS) were implanted in 34 complex intracranial aneurysms in 32 patients. In our series, 20 (58.8%) carotid-ophthalmic internal carotid artery (ICA), six (17.6%) cavernous ICA, two (5.9%) supraclinoid ICA, two (5.9%) petrosal ICA (the same patient- bilateral) and four (11.8%) posterior circulation aneurysms were treated. One of the posterior circulation lesions was a fenestrated-type aneurysm. Twenty wide-necked, saccular; eight neck remnant; four fusiform and two blister-like aneurysms were included in our series. SS were successfully implanted in all patients (100%). Misdeployment occurred in 17.6% of patients. In two of these patients adequate stent openness was achieved via Hyperglide balloon dilatation. Coil embolization in addition to SS placement was utilized in four aneurysms. One patient (3%) experienced transient morbidity due to a thromboembolic event and there was one mortality (3%) due to remote intraparenchymal haemorrhage. Complete occlusion of 27/33 (81.8 %) and 29/33 (87.9 %) aneurysms was achieved six and 12 months after the procedure, respectively. In-stent intimal hyperplasia was detected in 6.1 % patients. Flow-diverter Silk stent implantation is an effective method of treating complex aneurysms with acceptable mortality and morbidity rates. Complete occlusion is achieved in most of the complex aneurysms.

  19. Unilateral Agenesis of Internal Carotid Artery with Intercavernous Anastomosis: A Rare Case Report

    PubMed Central

    Kumaresh, Athiyappan; Vasanthraj, Praveen Kumar; Chandrasekharan, Anupama

    2015-01-01

    Unilateral agenesis of internal carotid artery (ICA) with intercavernous anastomosis is a rare congenital anomaly. We present a case of a 25-year-old female with 2-month history of holocranial headache. Neurological examination was unremarkable. Magnetic resonance imaging (MRI) with magnetic resonance angiography (MRA) showed absence of left ICA with an abnormal intercavernous vessel in the sella. Computed tomography (CT) showed absence of the left carotid canal. Doppler ultrasonography (USG) showed high resistance flow in the left common carotid artery (CCA). Since no hemorrhage or aneurysm was seen, patient was managed conservatively and is on regular follow-up. Based on our knowledge, this is the first case to demonstrate the features of unilateral agenesis of ICA with intercavernous anastomosis in X-ray, Doppler USG, CT, and MRI scans of the brain. PMID:25806142

  20. Reversible Cerebral Vasoconstriction Syndrome With Involvement of External Carotid Artery Branches

    PubMed Central

    Shaik, S.; Chhetri, S. K.; Roberts, G.; Wuppalapati, S.

    2014-01-01

    A 44-year-old woman presented with recurrent episodes of thunderclap headache. Neurological examination and computed tomography brain imaging were unremarkable. Cerebrospinal fluid findings were consistent with subarachnoid hemorrhage. Computed tomography angiography of the circle of Willis showed multiple areas of segmental vasoconstriction. This finding was confirmed on cerebral catheter angiography, with segmental vasoconstriction involving bilateral internal carotid, posterior cerebral, and external carotid branches. No aneurysm or other vascular abnormality was identified. She received treatment with nimodipine. A selective serotonin reuptake inhibitor, started 4 weeks earlier, was discontinued. Follow-up angiography after 3 months demonstrated complete resolution of the segmental vasoconstriction, confirming the diagnosis of reversible cerebral vasoconstriction syndrome (RCVS). She remained headache free at follow-up. To our knowledge, external carotid artery branch involvement in RCVS has been described only in one previous occasion. PMID:24982719

  1. Ruptured jejunal artery aneurysm

    PubMed Central

    Costa, Sílvia; Costa, Alexandre; Pereira, Tiago; Maciel, Jorge

    2013-01-01

    Visceral artery aneurysms (VAAs), unlike aortic aneurysms, are very rare, but are also a potentially lethal vascular disease. Jejunal artery aneurysms only account for less than 3% of VAAs, but have a 30% risk of rupture, with 20% death rate, presenting with only few and vague symptoms. We report the case of a 76-year-old man presenting at the emergency department (ED) with a crampy epigastric pain and vomiting. An ultrasound performed diagnosed free abdominal fluid and immediate CT scan diagnosed jejunal artery aneurysm spontaneously rupturing, followed by hypovolaemic shock. Emergent surgery was undertaken, and aneurysmectomy, followed by partial enterectomy with primary anastomosis were performed, because of segmentary jejunal ischaemia. The patient's recovery was unremarkable. High level of suspicion, rapid diagnosis capability and prompt surgical or endovascular intervention, as well as an effective teamwork in the ED are critical to avoid the devastating consequences of ruptured VAAs. PMID:23771962

  2. [Inflammatory abdominal aortic aneurysm].

    PubMed

    Mikami, Y; Kyogoku, M

    1994-08-01

    Inflammatory abdominal aortic aneurysm (IAAA) is a distinct clinicopathological entity, characterized by: (1) clinical presentation, such as back pain, weight loss, and increased ESR, (2) patchy and/or diffuse lymphoplasmacytic infiltration, and (3) marked periaortic fibrosis resulting in thickening of the aneurysmal wall and occasional retroperitoneal fibrosis. Its pathogenesis is unknown, but some authors support the theory that IAAA is a subtype of atherosclerotic abdominal aortic aneurysm because of close relationship between IAAA and atherosclerotic change. In this article, we describe clinical and histological features of IAAA on the basis of the literature and our review of 6 cases of IAAA, emphasizing the similarity and difference between IAAA and atherosclerotic abdominal aortic aneurysm. Our review supports that marked lamellar fibrosis completely replacing the media and adventitia, patchy lymphocytic infiltration (mostly B cells) and endarteritis obliterans are characteristic features of IAAA.

  3. Abdominal Aortic Aneurysm (AAA)

    MedlinePlus

    ... US) : Ultrasound is a highly accurate way to measure the size of an aneurysm. A physician may also use a special technique called Doppler ultrasound to examine blood flow through the aorta. Occasionally the aorta may not ...

  4. Aortic Aneurysm Statistics

    MedlinePlus

    ... this? Submit What's this? Submit Button Related CDC Web Sites Heart Disease Stroke High Blood Pressure Salt ... to Prevent and Control Chronic Diseases Million Hearts® Web Sites with More Information About Aortic Aneurysm For ...

  5. Cerebral Aneurysms Fact Sheet

    MedlinePlus

    ... affects the risk of rupture. What are the dangers? Aneurysms may burst and bleed into the brain, ... Research Coordinating Committees CounterACT Rigor & Reproducibility Scientific Resources Animal Models Cell/Tissue/DNA Clinical and Translational Resources ...

  6. What Is an Aneurysm?

    MedlinePlus

    ... rupture causes dangerous bleeding inside the body. A dissection is a split in one or more layers ... layers of the artery wall. Both rupture and dissection often are fatal. Overview Most aneurysms occur in ...

  7. Transluminal Attenuation Gradient for Thrombotic Risk Assessment in Kawasaki Disease Patients with Coronary Artery Aneurysms

    NASA Astrophysics Data System (ADS)

    Grande Gutierrez, Noelia; Kahn, Andrew; Burns, Jane; Marsden, Alison

    2014-11-01

    Kawasaki Disease (KD) can result in coronary aneurysms in up to 25% of patients if not treated early putting patients at risk of thrombus formation, myocardial infarction and sudden death. Clinical guidelines for administering anti-coagulation therapy currently rely on anatomy alone. Previous studies including patient specific modeling and computer simulations in KD patients have suggested that hemodynamic data can predict regions susceptible to thrombus formation. In particular, high Particle Residence Time gradient (PRTg) regions have shown to correlate with regions of thrombus formation. Transluminal Attenuation Gradient (TAG) is determined from the change in radiological attenuation per vessel length. TAG has been used for characterizing coronary artery stenoses, however this approach has not yet been used in aneurysmal vessels. The aim of this study is to analyze the correlation between TAG and PRTg in KD patients with aneurysms and evaluate the use of TAG as an index to quantify thrombotic risk. Patient specific anatomic models for fluids simulations were constructed from CT angiographic image data from 3 KD aneurysm patients and one normal control. TAG values for the aneurysm patients were markedly lower than for the non-aneurysmal patient (mean -18.38 vs. -2). In addition, TAG values were compared to PRTg obtained for each patient. Thrombotic risk stratification for KD aneurysms may be improved by incorporating TAG and should be evaluated in future prospective studies.

  8. Rheological Changes After Stenting of a Cerebral Aneurysm: A Finite Element Modeling Approach

    SciTech Connect

    Ohta, Makoto; Wetzel, Stephan G. Dantan, Philippe; Bachelet, Caroline; Lovblad, Karl O.; Yilmaz, Hasan; Flaud, Patrice; Ruefenacht, Daniel A.

    2005-12-15

    Hemodynamic changes in intracranial aneurysms after stent placement include the appearance of areas with stagnant flow and low shear rates. We investigated the influence of stent placement on blood flow velocity and wall shear stress of an intracranial aneurysm using a finite element modeling approach. To assess viscosity changes induced by stent placement, the rheology of blood as non-Newtonian fluid was taken into account in this model. A two-dimensional model with a parent artery, a smaller branching artery, and an aneurysm located at the bifurcation, before and after stent placement, was used for simulation. Flow velocity plots and wall shear stress before and after stent placement was calculated over the entire cardiac circle. Values for dynamic viscosity were calculated with a constitutive equation that was based on experimental studies and yielded a viscosity, which decreases as the shear rate increases. Stent placement lowered peak velocities in the main vortex of the aneurysm by a factor of at least 4 compared to peak velocities in the main artery, and it considerably decreased the wall shear stress of the aneurysm. Dynamic viscosity increases after stent placement persisted over a major part of the cardiac cycle, with a factor of up to 10, most pronounced near the dome of the aneurysm. Finite element modeling can offer insight into rheological changes induced by stent treatment of aneurysms and allows visualizing dynamic viscosity changes induced by stent placement.

  9. Management of Carotid Artery Trauma

    PubMed Central

    Lee, Thomas S.; Ducic, Yadranko; Gordin, Eli; Stroman, David

    2014-01-01

    With increased awareness and liberal screening of trauma patients with identified risk factors, recent case series demonstrate improved early diagnosis of carotid artery trauma before they become problematio. There remains a need for unified screening criteria for both intracranial and extracranial carotid trauma. In the absence of contraindications, antithrombotic agents should be considered in blunt carotid artery injuries, as there is a significant risk of progression of vessel injury with observation alone. Despite CTA being used as a common screening modality, it appears to lack sufficient sensitivity. DSA remains to be the gold standard in screening. Endovascular techniques are becoming more widely accepted as the primary surgical modality in the treatment of blunt extracranial carotid injuries and penetrating/blunt intracranial carotid lessions. Nonetheless, open surgical approaches are still needed for the treatment of penetrating extracranial carotid injuries and in patients with unfavorable lesions for endovascular intervention. PMID:25136406

  10. Aneurysmal Subarachnoid Hemorrhage.

    PubMed

    D'Souza, Stanlies

    2015-07-01

    Aneurysmal subarachnoid hemorrhage (SAH) is a worldwide health burden with high fatality and permanent disability rates. The overall prognosis depends on the volume of the initial bleed, rebleeding, and degree of delayed cerebral ischemia (DCI). Cardiac manifestations and neurogenic pulmonary edema indicate the severity of SAH. The International Subarachnoid Aneurysm Trial (ISAT) reported a favorable neurological outcome with the endovascular coiling procedure compared with surgical clipping at the end of 1 year. The ISAT trial recruits were primarily neurologically good grade patients with smaller anterior circulation aneurysms, and therefore the results cannot be reliably extrapolated to larger aneurysms, posterior circulation aneurysms, patients presenting with complex aneurysm morphology, and poor neurological grades. The role of hypothermia is not proven to be neuroprotective according to a large randomized controlled trial, Intraoperative Hypothermia for Aneurysms Surgery Trial (IHAST II), which recruited patients with good neurological grades. Patients in this trial were subjected to slow cooling and inadequate cooling time and were rewarmed rapidly. This methodology would have reduced the beneficial effects of hypothermia. Adenosine is found to be beneficial for transient induced hypotension in 2 retrospective analyses, without increasing the risk for cardiac and neurological morbidity. The neurological benefit of pharmacological neuroprotection and neuromonitoring is not proven in patients undergoing clipping of aneurysms. DCI is an important cause of morbidity and mortality following SAH, and the pathophysiology is likely multifactorial and not yet understood. At present, oral nimodipine has an established role in the management of DCI, along with maintenance of euvolemia and induced hypertension. Following SAH, hypernatremia, although less common than hyponatremia, is a predictor of poor neurological outcome.

  11. Aneurysmal Subarachnoid Hemorrhage

    PubMed Central

    2015-01-01

    Aneurysmal subarachnoid hemorrhage (SAH) is a worldwide health burden with high fatality and permanent disability rates. The overall prognosis depends on the volume of the initial bleed, rebleeding, and degree of delayed cerebral ischemia (DCI). Cardiac manifestations and neurogenic pulmonary edema indicate the severity of SAH. The International Subarachnoid Aneurysm Trial (ISAT) reported a favorable neurological outcome with the endovascular coiling procedure compared with surgical clipping at the end of 1 year. The ISAT trial recruits were primarily neurologically good grade patients with smaller anterior circulation aneurysms, and therefore the results cannot be reliably extrapolated to larger aneurysms, posterior circulation aneurysms, patients presenting with complex aneurysm morphology, and poor neurological grades. The role of hypothermia is not proven to be neuroprotective according to a large randomized controlled trial, Intraoperative Hypothermia for Aneurysms Surgery Trial (IHAST II), which recruited patients with good neurological grades. Patients in this trial were subjected to slow cooling and inadequate cooling time and were rewarmed rapidly. This methodology would have reduced the beneficial effects of hypothermia. Adenosine is found to be beneficial for transient induced hypotension in 2 retrospective analyses, without increasing the risk for cardiac and neurological morbidity. The neurological benefit of pharmacological neuroprotection and neuromonitoring is not proven in patients undergoing clipping of aneurysms. DCI is an important cause of morbidity and mortality following SAH, and the pathophysiology is likely multifactorial and not yet understood. At present, oral nimodipine has an established role in the management of DCI, along with maintenance of euvolemia and induced hypertension. Following SAH, hypernatremia, although less common than hyponatremia, is a predictor of poor neurological outcome. PMID:25272066

  12. Splenic artery aneurysm.

    PubMed

    Tcbc-Rj, Rui Antônio Ferreira; Ferreira, Myriam Christina Lopes; Ferreira, Daniel Antônio Lopes; Ferreira, André Gustavo Lopes; Ramos, Flávia Oliveira

    2016-01-01

    Splenic artery aneurysms - the most common visceral artery aneurysms - are found most often in multiparous women and in patients with portal hypertension. Indications for treatment of splenic artery aneurysm or pseudoaneurysm include specific symptoms, female gender and childbearing age, presence of portal hypertension, planned liver transplantation, a pseudoaneurysm of any size, and an aneurysm with a diameter of more than 2.5cm. Historically, the treatment of splenic artery aneurysm has been surgical ligation of the splenic artery, ligation of the aneurysm, or aneurysmectomy with or without splenectomy, depending on the aneurysm location. There are other percutaneous interventional techniques. The authors present a case of a splenic artery aneurysm in a 51-year-old woman, detected incidentally. RESUMO Aneurismas da artéria esplênica - os aneurismas arteriais viscerais mais comuns - são encontrados mais frequentemente em mulheres multíparas e em pacientes com hipertensão portal. As indicações para o seu tratamento incluem sintomas específicos, sexo feminino e idade fértil, presença de hipertensão portal, paciente em fila de transplante hepático, um pseudoaneurisma de qualquer tamanho, e um aneurisma com um diâmetro superior a 2,5cm. Historicamente, o tratamento do aneurisma da artéria esplênica tem sido a ligadura cirúrgica da artéria esplênica, a ligadura do aneurisma ou a aneurismectomia, com ou sem esplenectomia, dependendo do local do aneurisma. Existem outras técnicas intervencionistas percutâneas. Os autores apresentam o caso de um aneurisma de artéria esplênica em uma mulher de 51 anos de idade, diagnosticado incidentalmente.

  13. How Is Carotid Artery Disease Treated?

    MedlinePlus

    ... from the NHLBI on Twitter. How Is Carotid Artery Disease Treated? Treatments for carotid artery disease may ... plaque removed and normal blood flow restored. Carotid Artery Angioplasty and Stenting Doctors use a procedure called ...

  14. How Can Carotid Artery Disease Be Prevented?

    MedlinePlus

    ... from the NHLBI on Twitter. How Can Carotid Artery Disease Be Prevented? Taking action to control your risk factors can help prevent or delay carotid artery disease and stroke . Your risk for carotid artery ...

  15. Angiographic analysis for phantom simulations of endovascular aneurysm treatments with a new fully retrievable asymmetric flow diverter

    NASA Astrophysics Data System (ADS)

    Yoganand, Aradhana; Wood, Rachel P.; Jimenez, Carlos; Siddiqui, Adnan; Snyder, Kenneth; Setlur Nagesh, S. V.; Bednarek, D. R.; Rudin, S.; Baier, Robert; Ionita, Ciprian N.

    2015-03-01

    Digital Subtraction Angiography (DSA) is the main diagnostic tool for intracranial aneurysms (IA) flow-diverter (FD) assisted treatment. Based on qualitative contrast flow evaluation, interventionists decide on subsequent steps. We developed a novel fully Retrievable Asymmetric Flow-Diverter (RAFD) which allows controlled deployment, repositioning and detachment achieve optimal flow diversion. The device has a small low porosity or solid region which is placed such that it would achieve maximum aneurysmal in-jet flow deflection with minimum impairment to adjacent vessels. We tested the new RAFD using a flow-loop with an idealized and a patient specific IA phantom in carotid-relevant physiological conditions. We positioned the deflection region at three locations: distally, center and proximally to the aneurysm orifice and analyzed aneurysm dome flow using DSA derived maps for mean transit time (MTT) and bolus arrival times (BAT). Comparison between treated and untreated (control) maps quantified the RAFD positioning effect. Average MTT, related to contrast presence in the aneurysm dome increased, indicating flow decoupling between the aneurysm and parent artery. Maximum effect was observed in the center and proximal position (~75%) of aneurysm models depending on their geometry. BAT maps, correlated well with inflow jet direction and magnitude. Reduction and jet dispersion as high as about 50% was observed for various treatments. We demonstrated the use of DSA data to guide the placement of the RAFD and showed that optimum flow diversion within the aneurysm dome is feasible. This could lead to more effective and a safer IA treatment using FDs.

  16. Is it safe to sacrifice the superior hypophyseal artery in aneurysm clipping? A report of two cases.

    PubMed

    El Refaee, Ehab Ahmed; Baldauf, Jörg; Balau, Valentin; Rosenstengel, Christian; Schroeder, Henry

    2013-12-01

    Clipping of paraclinoid internal carotid artery aneurysms related to the superior hypophyseal artery (SHA) carries risk of occlusion of this artery when originating distal to the neck of the aneurysm. Sometimes it is inevitable to sacrifice the artery to achieve total aneurysm occlusion. Otherwise a residual aneurysm would remain, which may lead to aneurysm regrowth and subsequent rupture. However, consequences of SHA sacrifice are rarely reported in the literature. In the two presented cases, the SHA was found originating distal to the neck and within the wall of the aneurysm, making the optimal clipping of the aneurysm at the neck unfeasible without trapping of the SHA. Intraoperative indocyanine green (ICG) angiography revealed a retrograde blood flow in the SHA distal to the clip in both patients, indicating some collateral circulation. No endocrinologic deficits were encountered after surgery. The vision was not affected in one patient. In the other patient, bilateral visual field defects occurred, which improved partially in the follow-up 2 months after surgery. The consequences of SHA occlusion are difficult to predict. A large variety of anatomical variations of the vascular anatomy exists. Intraoperative ICG angiography may help to estimate collateral blood flow but is not able to predict visual decline. Although final conclusions cannot be drawn from two patients, it seems that in case of multiplicity of superior hypophyseal complex, sacrifice of one even larger branch is safe. However, visual sequelae have to be taken into consideration when a single SHA has to be sacrificed for total aneurysm clipping.

  17. AView: An Image-based Clinical Computational Tool for Intracranial Aneurysm Flow Visualization and Clinical Management.

    PubMed

    Xiang, Jianping; Antiga, Luca; Varble, Nicole; Snyder, Kenneth V; Levy, Elad I; Siddiqui, Adnan H; Meng, Hui

    2016-04-01

    Intracranial aneurysms (IAs) occur in around 3% of the entire population. IA rupture is responsible for the most devastating type of hemorrhagic strokes, with high fatality and disability rates as well as healthcare costs. With increasing detection of unruptured aneurysms, clinicians are routinely faced with the dilemma whether to treat IA patients and how to best treat them. Hemodynamic and morphological characteristics are increasingly considered in aneurysm rupture risk assessment and treatment planning, but currently no computational tools allow routine integration of flow visualization and quantitation of these parameters in clinical workflow. In this paper, we introduce AView, a prototype of a clinician-oriented, integrated computation tool for aneurysm hemodynamics, morphology, and risk and data management to aid in treatment decisions and treatment planning in or near the procedure room. Specifically, we describe how we have designed the AView structure from the end-user's point of view, performed a pilot study and gathered clinical feedback. The positive results demonstrate AView's potential clinical value on enhancing aneurysm treatment decision and treatment planning.

  18. Flow Changes after Endovascular Treatment of a Wide-Neck Anterior Communicating Artery Aneurysm by using X-configured Kissing Stents (Cross-Kissing Stents) Technique

    SciTech Connect

    Zelenak, Kamil; Zelenakova, Jana; DeRiggo, Julius; Kurca, Egon; Boudny, Jaroslav; Polacek, Hubert

    2011-12-15

    Endovascular treatment for a wide-neck anterior communicating artery (AcomA) aneurysm remains technically challenging. Stent-assisted embolization has been proposed as an alternative of treatment of complex aneurysms. The X-configuration double-stent-assisted technique was used to achieve successful coiling of wide-neck AcomA aneurysm. Implanted stent can alter intra-arterial flow. Follow-up angiograms 4 months later showed flow changes due to used X-technique of stents implantation and filling of the anterior cerebral artery from the opposite internal carotid artery.

  19. Leo Stent for Endovascular Treatment of Broad-Necked and Fusiform Intracranial Aneurysms

    PubMed Central

    Juszkat, R.; Nowak, S.; Smól, S.; Kociemba, W.; Blok, T.; Zarzecka, A.

    2007-01-01

    Summary The advent of intracranial stents has widened the indications for endovascular treatment of broad-necked and fusiform aneurysms. Leo stent is a self-expandable, nitinol, braided stent dedicated to intracranial vessels. The aim of this study is to present our experience in endovascular treatment of broad-necked and fusiform intracranial aneurysms using self-expanding, nitinol Leo stents. Between February 2004 and November 2006, 25 broad-necked and three fusiform aneurysms in 28 patients were treated using Leo stents in our centre. There were 18 patients who experienced acute subarachnoid haemorrhage due to aneurysm rupture, two patients who experienced SAH at least 12 months ago and in eight patients aneurysms were found incidentally. Aneurysms were located as follows: internal carotid artery15, basilar artery5, basilar tip3, posterior inferior cerebral artery2, M1/M2 segment1, A2 segment1 and vertebral artery1. There were no difficulties with stent deployment and delivery. All patients after acute SAH (n=18) underwent stent implantation and coil embolization in one procedure. The remaining patients underwent coil embolization in a staged procedure. Immediate aneurysm occlusion of more than 95% was achieved in all patients who underwent stent placement and coil embolization in one procedure. There were three thromboembolic complications encountered in patients in an acute setting of SAH, preloaded only on acetylsalicylic acid. Use of abciximab led to patency within the stent and parent vessel. However, one of these patients presented rebleeding from the aneurysm during administration of abciximab and died. Application of Leo stents in cases of broadnecked and fusiform intracranial aneurysms is safe and effective with a low complication rate. PMID:20566117

  20. Rasmussen's aneurysm: A forgotten scourge☆

    PubMed Central

    Chatterjee, Kshitij; Colaco, Brendon; Colaco, Clinton; Hellman, Michael; Meena, Nikhil

    2015-01-01

    Rasmussen's aneurysm is an inflammatory pseudo-aneurysmal dilatation of a branch of pulmonary artery adjacent to a tuberculous cavity. Life threatening massive hemoptysis from the rupture of a Rasmussen's aneurysm is an uncommon yet life threatening complication of cavitary tuberculosis (TB). We present a case of a young woman who presented with low-grade fever and hemoptysis. Computed tomographic (CT) angiography showed biapical cavitary lesions and actively bleeding aneurysms involving pulmonary artery, which successfully underwent glue embolization. PMID:26744661

  1. Carotid Artery Stenting versus Endarterectomy

    PubMed Central

    Gahremanpour, Amir; Perin, Emerson C.; Silva, Guilherme

    2012-01-01

    For about 2 decades, investigators have been comparing carotid endarterectomy with carotid artery stenting in regard to their effectiveness and safety in treating carotid artery stenosis. We conducted a systematic review to summarize and appraise the available evidence provided by randomized trials, meta-analyses, and registries comparing the clinical outcomes of the 2 procedures. We searched the MEDLINE, SciVerse Scopus, and Cochrane databases and the bibliographies of pertinent textbooks and articles to identify these studies. The results of clinical trials and, consequently, the meta-analyses of those trials produced conflicting results regarding the comparative effectiveness and safety of carotid endarterectomy and carotid stenting. These conflicting results arose because of differences in patient population, trial design, outcome measures, and variability among centers in the endovascular devices used and in operator skills. Careful appraisal of the trials and meta-analyses, particularly the most recent and largest National Institutes of Healthsponsored trial (the Carotid Revascularization Endarterectomy vs Stenting Trial [CREST]), showed that carotid stenting and endarterectomy were associated with similar rates of death and disabling stroke. Within the 30-day periprocedural period, carotid stenting was associated with higher risks of stroke, especially for patients aged >70 years, whereas carotid endarterectomy was associated with a higher risk of myocardial infarction. The slightly higher cost of stenting compared with endarterectomy was within an acceptable range by cost-effectiveness standards. We conclude that carotid artery stenting is an equivalent alternative to carotid endarterectomy when patient age and anatomy, surgical risk, and operator experience are considered in the choice of treatment approach. PMID:22949763

  2. Mouse models of intracranial aneurysm.

    PubMed

    Wang, Yutang; Emeto, Theophilus I; Lee, James; Marshman, Laurence; Moran, Corey; Seto, Sai-wang; Golledge, Jonathan

    2015-05-01

    Subarachnoid hemorrhage secondary to rupture of an intracranial aneurysm is a highly lethal medical condition. Current management strategies for unruptured intracranial aneurysms involve radiological surveillance and neurosurgical or endovascular interventions. There is no pharmacological treatment available to decrease the risk of aneurysm rupture and subsequent subarachnoid hemorrhage. There is growing interest in the pathogenesis of intracranial aneurysm focused on the development of drug therapies to decrease the incidence of aneurysm rupture. The study of rodent models of intracranial aneurysms has the potential to improve our understanding of intracranial aneurysm development and progression. This review summarizes current mouse models of intact and ruptured intracranial aneurysms and discusses the relevance of these models to human intracranial aneurysms. The article also reviews the importance of these models in investigating the molecular mechanisms involved in the disease. Finally, potential pharmaceutical targets for intracranial aneurysm suggested by previous studies are discussed. Examples of potential drug targets include matrix metalloproteinases, stromal cell-derived factor-1, tumor necrosis factor-α, the renin-angiotensin system and the β-estrogen receptor. An agreed clear, precise and reproducible definition of what constitutes an aneurysm in the models would assist in their use to better understand the pathology of intracranial aneurysm and applying findings to patients.

  3. Thoracic aorta aneurysm open repair in heart transplant recipient; the anesthesiologist's perspective

    PubMed Central

    Monaco, Fabrizio; Oriani, Alessandro; De Luca, Monica; Bignami, Elena; Sala, Alessandra; Chiesa, Roberto; Melissano, Germano; Zangrillo, Alberto

    2016-01-01

    Many years following transplantation, heart transplant recipients may require noncardiac major surgeries. Anesthesia in such patients may be challenging due to physiological and pharmacological problems regarding allograft denervation and difficult immunosuppressive management. Massive hemorrhage, hypoperfusion, renal, respiratory failure, and infections are some of the most frequent complications related to thoracic aorta aneurysm repair. Understanding how to optimize hemodynamic and infectious risks may have a substantial impact on the outcome. This case report aims at discussing risk stratification and anesthetic management of a 54-year-old heart transplant female recipient, affected by Marfan syndrome, undergoing thoracic aorta aneurysm repair. PMID:26750703

  4. The Changes of Flow Characteristics Caused by a Stent in Fusiform Aneurysm Models

    DTIC Science & Technology

    2007-11-02

    human carotid artery. B. Flow Visualization We used a flow visualization method incorporating photochromic dye in order to observe the flow...fields. A photochromic dye shows photochromic behavior by changing its color by the excitation of light of an appropriate wavelength. We used TNSB (1...visualization technique using photochromic dye was applied to the fusiform aneurysm models. The qualitative observation of tracer lines showed

  5. Disappearance of a small intracranial aneurysm as a result of vessel straightening and in-stent stenosis following use of an Enterprise vascular reconstruction device.

    PubMed

    Takemoto, Koichiro; Tateshima, Satoshi; Rastogi, Sachin; Gonzalez, Nestor; Jahan, Reza; Duckwiler, Gary; Vinuela, Fernando

    2013-01-17

    In-stent stenosis after stent-assisted coil embolization is a rare but well-known complication. A 32-year-old woman with an unruptured wide-necked left internal carotid artery (ICA) terminus aneurysm and an ipsilateral very small anterior choroidal artery aneurysm underwent stent-assisted coil embolization for the ICA terminus aneurysm. The 4-month follow-up angiography revealed diffuse in-stent stenosis and disappearance of the untreated anterior choroidal artery aneurysm, retaining the patency of the anterior choroidal artery. To our knowledge, this is the first report to demonstrate the course of in-stent stenosis and disappearance of an untreated small intracranial aneurysm as a result. We report this unique case and discuss the interesting mechanism underlying this phenomenon, and also provide a review of the relevant literature.

  6. Disappearance of a small intracranial aneurysm as a result of vessel straightening and in-stent stenosis following use of an Enterprise vascular reconstruction device.

    PubMed

    Takemoto, Koichiro; Tateshima, Satoshi; Rastogi, Sachin; Gonzalez, Nestor; Jahan, Reza; Duckwiler, Gary; Vinuela, Fernando

    2014-01-01

    In-stent stenosis after stent-assisted coil embolization is a rare but well-known complication. A 32-year-old woman with an unruptured wide-necked left internal carotid artery (ICA) terminus aneurysm and an ipsilateral very small anterior choroidal artery aneurysm underwent stent-assisted coil embolization for the ICA terminus aneurysm. The 4-month follow-up angiography revealed diffuse in-stent stenosis and disappearance of the untreated anterior choroidal artery aneurysm, retaining the patency of the anterior choroidal artery. To our knowledge, this is the first report to demonstrate the course of in-stent stenosis and disappearance of an untreated small intracranial aneurysm as a result. We report this unique case and discuss the interesting mechanism underlying this phenomenon, and also provide a review of the relevant literature.

  7. Systemic Pulsatile Pressure in Type II Endoleaks After Stent Grafting of Experimental Abdominal Aortic Aneurysms

    SciTech Connect

    Pitton, Michael Bernhard Schmenger, Patrick; Dueber, Christoph; Neufang, Achim; Thelen, Manfred

    2003-06-15

    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 = 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.

  8. Covered Stents in the Treatment of Peripheral Arterial Aneurysms: Procedural Results and Midterm Follow-Up

    SciTech Connect

    Beregi, Jean-Paul; Prat, Alain; Willoteaux, Serge; Vasseur, Marc-Antoine; Boularand, Valerie; Desmoucelle, Frederic

    1999-01-15

    Purpose: To evaluate initial and midterm results of percutaneous treatment of peripheral aneurysms using covered stents. Methods: Between June 1994 and December 1997 we used covered stents (EndoPro System or Passager) on 19 patients with peripheral aneurysms (7 iliac, 5 subclavian, 3 femoral, 3 popliteal, 1 carotid). Results: Successful aneurysm exclusion was achieved in 18 of 19 patients (95%). In the short term (<30 days), one patient died of puncture site hemorrhage complicated by myocardial infarction; two femoral stents were surgically removed because of leakage. At subsequent follow-up (mean 20 months) two further unrelated deaths occurred. At 1 year (intention-to-treat) the stent was patent in 13 of 19 patients (68%) and the aneurysm was excluded in 17 of 19 (89%). Conclusion: Treatment of peripheral aneurysms with covered stents has a high rate of immediate procedural success. Continued exclusion of the aneurysms is achieved in a large proportion of patients but there is a relatively high rate of stent thrombosis.

  9. Wall shear stress and pressure distribution on aneurysms and infundibulae in the posterior communicating artery bifurcation.

    PubMed

    Baek, Hyoungsu; Jayaraman, Mahesh V; Karniadakis, George Em

    2009-12-01

    A growing number of cases of rupture at an infundibulum, progression of infundibulum to a frank aneurysm, and subarachnoid hemorrhage (SAH) in the posterior communicating artery (PCoA) have been reported. Using patient-specific geometric models of the supraclinoid internal carotid artery (ICA) with PCoA infundibulum or aneurysm, high-resolution computational fluid dynamics simulations were performed by solving the Navier-Stokes equations with a spectral/hp element method. Simulation results show that the flow impinges at the distal wall of infundibulum near the outside of the ICA bend and creates a region of higher pressure (4-5 mmHg) surrounded by a band of a high wall shear stress (WSS) (20-30 N/m(2) on average). At the proximal end of the infundibulum, another stagnation area is formed characterized by low WSS (<1 N/m(2)) and high oscillating shear index. This impingement region seems to coincide with the locations of the rupture of infundibulae or progression to aneurysms. In addition, the pulsatile flow becomes unstable due to the presence of aneurysms or aneurysm-like infundibulae, and this leads to WSS temporal fluctuations inside the aneurysm, which may accelerate the degenerative processes in the vessel walls.

  10. The effect of aneurismal-wall mechanical properties on patient-specific hemodynamic simulations: two clinical case reports

    NASA Astrophysics Data System (ADS)

    Chen, Jialiang; Wang, Shengzhang; Ding, Guanghong; Yang, Xinjian; Li, Haiyun

    2009-10-01

    Hemodynamic factors such as the wall shear stress play an important role in the pathogenesis and treatment of cerebral aneurysms. In present study, we apply computational fluid-structure interaction analyses on cerebral aneurysms with two different constitutive relations for aneurismal wall in order to investigate the effect of the aneurismal wall mechanical properties on the simulation results. We carry out these analyses by using two patient-specific models of cerebral aneurysms of different sizes located in different branches of the circle of Willis. The models are constructed from 3D rotational angiography image data and blood flow dynamics is studied under physiologically representative waveform of inflow. From the patient models analyzed in this investigation, we find that the deformations of cerebral aneurysms are very small. But due to the nonlinear character of the Navier-Stokes equations, these small deformations could have significant influences on the flow characteristics. In addition, we find that the aneurismal-wall mechanical properties have great effects on the deformation distribution of the aneurysm, which also affects the wall shear stress distribution and flow patterns. Therefore, how to define a proper constitutive relation for aneurismal wall should be considered carefully in the hemodynamic simulation.

  11. Hemodynamics in an Aorta with Bicuspid and Trileaflet Valves

    NASA Astrophysics Data System (ADS)

    Gilmanov, Anvar; Sotiropoulos, Fotis

    2015-11-01

    Bicuspid aortic valve (BAV) is a congenital heart defect that has been associated with serious aortopathies, such as ascending aortic aneurysm, aortic stenosis, aortic regurgitation, infective endocarditis, aortic dissection, calcific aortic valve and dilatation of ascending aorta. Two main hypotheses - the genetic and the hemodynamic are discussed in literature to explain the development and progression of aortopathies in patients with BAV. In this study we seek to investigate the possible role of hemodynamic factors as causes of BAV-associated aortopathy. We employ the Curvilinear Immersed Boundary (CURVIB) method coupled with an efficient thin-shell finite element (TS-FE) formulation for tissues to carry out fluid-structure interaction simulations of a healthy tri-leaflet aortic valve (TAV) and a BAV placed in the same anatomic aorta. The computed results reveal major differences between the TAV and BAV flow patterns. These include: the dynamics of the aortic valve vortex ring formation and break up; the large scale flow patterns in the ascending aorta; and the shear stress magnitude on the aortic wall. The computed results are in qualitative agreement with in vivo Magnetic Resonance Imaging (MRI) data and suggest that the linkages between BAV aortopathy and hemodynamics deserve further investigation. This work is supported by the Lillehei Heart Institute at the University of Minnesota and the Minnesota Supercomputing Institute.

  12. Removal of anterior clinoid process for basilar tip aneurysm: clinical and cadaveric analysis.

    PubMed

    Sato, S; Sato, M; Oizumi, T; Nishizawa, M; Ishikawa, M; Inamasu, G; Kawase, T

    2001-06-01

    The difficulty in the operation for basilar tip aneurysm is the restriction in surgical working space. To resolve this problem, aggressive skull base surgery has been reported, but these techniques are not prevalent. Pterional and subtemporal approaches are commonly used for basilar tip aneurysms. In an attempt to increase the surgical working space during the pterional approach, the anterior clinoid process and the roof of the optic nerve were removed extradurally to increase the mobilization of the intracranial internal carotid artery and optic nerve. The effects of removing the anterior clinoid process and microanatomy in the perioptic area were analyzed by cadaveric procedures in 10 cases (20 sides). With this procedure, the internal carotid artery can be retracted medially with a spatula 6.1 +/- 0.8 mm (mean +/- SD). The length and the area of dural fold in the bone defect region in the optic canal roof are 2.1 mm and 13.6 mm. In 10 clinical cases, this procedure allowed enough space to approach the basilar tip aneurysm without disturbing the internal carotid artery blood flow. The clinical outcome was satisfactory.

  13. Establishment of the intracranial hemodynamic model based on contrast medium and clinical applications

    PubMed Central

    Cheng, Yaoer; He, Wen

    2016-01-01

    Abstract Ischemic cerebrovascular diseases are one of the most common vascular diseases in aged people and CT perfusion (CTP) is a very popular tool to detect the ischemic changes in brain vascular. The present study aims to establish a novel intracranial hemodynamic model to simulate anterior cerebral artery blood flow, and compare the actual and simulated hemodynamic parameters of healthy people and patients with carotid stenosis or occlusion. A mathematical model of the intracranial hemodynamic was generated using MATLAB software, and data from patients with or without infarct disease (57 and 44 cases, respectively) were retrospectively collected to test the new model. The actual time-density curve (TDC) of anterior cerebral artery was obtained from the original intracranial CTP data, and simulated TDC was calculated from our intracranial hemodynamic model. All model parameters were adjusted according to patients’ sex, height, and weight. Time to peak enhancement (TTP), maximum enhancement (ME), and mean transit time (MTT) were selected to evaluate the status of hemodynamics. In healthy people, there were no significant differences of TTP and ME between actual and simulated curves. For patients with infarct symptoms, ME was significantly decreased in actual data compared with simulated curve, while there was no obvious difference of TTP between actual and simulated data. Moreover, MTT was delayed in infarct patients compared with healthy people. Our group generated a computer-based, physiologic model to simulate intracranial hemodynamics. The model successfully simulated anterior cerebral artery hemodynamics in normal healthy people and showed noncompliant ME and MTT in infarct patients, reflecting their abnormal cerebral hemodynamic status. The digital model is reliable and may help optimize the protocol of contrast medium enhancement in intracranial CT, and provide a solid tool to study intracranial hemodynamics. PMID:27930555

  14. [Inflammatory abdominal aortic aneurysm].

    PubMed

    Siebenmann, R; Schneider, K; von Segesser, L; Turina, M

    1988-06-11

    348 cases of abdominal aortic aneurysm were reviewed for typical features of inflammatory aneurysm (IAAA) (marked thickening of aneurysm wall, retroperitoneal fibrosis and rigid adherence of adjacent structures). IAAA was present in 15 cases (14 male, 1 female). When compared with patients who had ordinary aneurysms, significantly more patients complained of back or abdominal pain (p less than 0.01). Erythrocyte sedimentation rate was highly elevated. Diagnosis was established in 7 of 10 computed tomographies. 2 patients underwent emergency repair for ruptured aneurysm. Unilateral ureteral obstruction was present in 4 cases and bilateral in 1. Repair of IAAA was performed by a modified technique. Histological examination revealed thickening of the aortic wall, mainly of the adventitial layer, infiltrated by plasma cells and lymphocytes. One 71-year-old patient operated on for rupture of IAAA died early, and another 78-year-old patient after 5 1/2 months. Control computed tomographies revealed spontaneous regression of inflammatory infiltration after repair. Equally, hydronephrosis due to ureteral obstruction could be shown to disappear or at least to decrease. IAAA can be diagnosed by computed tomography with high sensitivity. Repair involves low risk, but modification of technique is necessary. The etiology of IAAA remains unclear.

  15. [Inflammatory abdominal aortic aneurysm].

    PubMed

    Ziaja, K; Sedlak, L; Urbanek, T; Kostyra, J; Ludyga, T

    2000-01-01

    The reported incidence of inflammatory abdominal aortic aneurysm (IAAA) is from 2% to 14% of patients with abdominal aortic aneurysm and the etiology of this disease is still discussed--according to the literature several pathogenic theories have been proposed. From 1992 to 1997 32 patients with IAAA were operated on. The patients were mostly symptomatic--abdominal pain was present in 68.75% cases, back pain in 31.25%, fever in 12.5% and weight loss in 6.25% of the operated patients. In all the patients ultrasound examination was performed, in 4 patients CT and in 3 cases urography. All the patients were operated on and characteristic signs of inflammatory abdominal aortic aneurysm like: thickened aortic wall, perianeurysmal infiltration or retroperitoneal fibrosis with involvement of retroperitoneal structures were found. In all cases surgery was performed using transperitoneal approach; in three cases intraoperatively contiguous abdominal organs were injured, which was connected with their involvement into periaortic inflammation. In 4 cases clamping of the aorta was done at the level of the diaphragmatic hiatus. 3 patients (9.37%) died (one patient with ruptured abdominal aortic aneurysm). Authors present diagnostic procedures and the differences in the surgical tactic, emphasizing the necessity of the surgical therapy in patients with inflammatory abdominal aortic aneurysm.

  16. [Carotid duplex ultrasonography for neurosurgeons].

    PubMed

    Sadahiro, Hirokazu; Ishihara, Hideyuki; Oka, Fumiaki; Suzuki, Michiyasu

    2011-12-01

    Carotid duplex ultrasonography (CDU) is one of the most well-known imaging methods for arteriosclerosis and ischemic stroke. For neurosurgeons, it is very important for the details of carotid plaque to be thoroughly investigated by CDU. Symptomatic carotid plaque is very fragile and easily changes morphologically, and so requires frequent CDU examination. Furthermore, after carotid endarterectomy (CEA) and carotid artery stenting (CAS), restenosis is evaluated with CDU. CDU facilitates not only morphological imaging in the B mode, but also allows a flow study with color Doppler and duplex imaging. So, CDU can help assess the presence of proximal and intracranial artery lesions in spite of only having a cervical view, and the patency of the extracranial artery to intracranial artery bypass is revealed with CDU, which shows a rich velocity and low pulsatility index (PI) in duplex imaging. For the examiner, it is necessary to ponder on what duplex imaging means in examinations, and to summarize all imaging finding.

  17. Blood flow dynamic improvement with aneurysm repair detected by a patient-specific model of multiple aortic aneurysms.

    PubMed

    Sughimoto, Koichi; Takahara, Yoshiharu; Mogi, Kenji; Yamazaki, Kenji; Tsubota, Ken'ichi; Liang, Fuyou; Liu, Hao

    2014-05-01

    Aortic aneurysms may cause the turbulence of blood flow and result in the energy loss of the blood flow, while grafting of the dilated aorta may ameliorate these hemodynamic disturbances, contributing to the alleviation of the energy efficiency of blood flow delivery. However, evaluating of the energy efficiency of blood flow in an aortic aneurysm has been technically difficult to estimate and not comprehensively understood yet. We devised a multiscale computational biomechanical model, introducing novel flow indices, to investigate a single male patient with multiple aortic aneurysms. Preoperative levels of wall shear stress and oscillatory shear index (OSI) were elevated but declined after staged grafting procedures: OSI decreased from 0.280 to 0.257 (first operation) and 0.221 (second operation). Graftings may strategically counter the loss of efficient blood delivery to improve hemodynamics of the aorta. The energy efficiency of blood flow also improved postoperatively. Novel indices of pulsatile pressure index (PPI) and pulsatile energy loss index (PELI) were evaluated to characterize and quantify energy loss of pulsatile blood flow. Mean PPI decreased from 0.445 to 0.423 (first operation) and 0.359 (second operation), respectively; while the preoperative PELI of 0.986 dropped to 0.820 and 0.831. Graftings contributed not only to ameliorate wall shear stress or oscillatory shear index but also to improve efficient blood flow. This patient-specific modeling will help in analyzing the mechanism of aortic aneurysm formation and may play an important role in quantifying the energy efficiency or loss in blood delivery.

  18. Cerebral hemodynamics and endothelial function in patients with Fabry disease

    PubMed Central

    2013-01-01

    Background Cerebral vasculopathy have been described in Fabry disease, in which altered cerebral blood flow, vascular remodelling or impairment of endothelial function could be involved. Our study aims to evaluate these three possibilities in a group of Fabry patients, and compare it to healthy controls. Methods Cerebral hemodynamics, vascular remodelling and systemic endothelial function were investigated in 10 Fabry patients and compared to data from 17 healthy controls. Transcranial Doppler was used to study blood flow velocity of intracranial arteries and cerebral vasomotor reactivity. For the study of vascular remodelling and endothelial function, intima-media thickness of common carotid arteries, flow-mediated dilation in brachial artery and serum levels of soluble VCAM-1, TNF-α, high-sensitive CRP and IL-6 were measured. Differences between groups were evaluated using appropriate tests. Results No relevant differences were observed in cerebral hemodynamic parameters, intima-media thickness or flow-mediated dilation. There was a trend for low serum levels of IL-6 and high serum levels of TNF-α and high-sensitive CRP in Fabry patients; plasma concentrations of soluble VCAM-1 were significantly higher in Fabry disease patients than in healthy volunteers (p = 0.02). Conclusions In our sample, we did not find relevant alterations of cerebral hemodynamics in Fabry disease patients. Increased levels of plasmatic endothelial biomarkers seem to be the most important feature indicative of possible vascular dysfunction in Fabry disease patients. PMID:24207059

  19. Clinical results of carotid artery stenting versus carotid endarterectomy

    PubMed Central

    Akinci, Tuba; Derle, Eda; Kibaroğlu, Seda; Harman, Ali; Kural, Feride; Cınar, Pınar; Kilinc, Munire; Akay, Hakki T.; Can, Ufuk; Benli, Ulku S.

    2016-01-01

    Objective: To review our results of carotid artery stenting (CAS) and carotid endarterectomy (CEA). Methods: We evaluated the medical records of patients undergoing carotid artery revascularization procedure, between 2001 and 2013 in Baskent University Hospital, Ankara, Turkey. Carotid artery stenting or CEA procedures were performed in patients with asymptomatic carotid stenosis (≥70%) or symptomatic stenosis (≥50%). Demographic data, procedural details, and clinical outcomes were recorded. Primary outcome measures were in 30-day stroke/transient ischemic attacks (TIA)/amaurosis fugax or death. Secondary outcome measures were nerve injury, bleeding complications, length of stay in hospital, stroke, restenosis (ICA patency), and all-cause death during long-term follow-up. Results: One hundred ninety-four CEA and 115 CAS procedures were performed for symptomatic and/or asymptomatic carotid artery stenosis. There is no significant differences 30-day mortality and neurologic morbidity between CAS (13%) and CEA procedures (7.7%). Length of stay in hospital were significantly longer in CEA group (p=0.001). In the post-procedural follow up, only in symptomatic patients, restenosis rate was higher in the CEA group (p=.045). The other endpoints did not differ significantly. Conclusions: Endovascular stent treatment of carotid artery atherosclerotic disease is an alternative for vascular surgery, especially for patients that are high risk for standard CEA. The increasing experience, development of cerebral protection systems and new treatment protocols increases CAS feasibility. PMID:27744460

  20. Juxtaphyseal aneurysmal bone cysts.

    PubMed

    Rizzo, M; Dellaero, D T; Harrelson, J M; Scully, S P

    1999-07-01

    Aneurysmal bone cysts are benign primary or secondary lesions that commonly arise in long bones and often before skeletal maturity. Little has been written about aneurysmal bone cysts that abut the physeal plate. The records of 15 patients with juxtaphyseal aneurysmal bone cysts were reviewed. Fourteen of the patients were referred with abnormal radiographs after evaluation for pain in the affected limb. One patient presented with abnormal radiographs after fracture about the aneurysmal bone cyst. None of the patients had evidence of growth plate disruption. The children's ages ranged from 2 to 14 years, with a mean of 9.8 years. There were 10 boys and five girls. Lesion locations included: six in the proximal tibia, three in the distal fibula, two in the distal tibia, two in the proximal femur, one in the distal femur, and one in the distal radius. All of the lesions abutted the physeal plate and fell into one of the types in Campanacci's classification of juxtaphyseal aneurysmal bone cysts. Three lesions were classified as Type 1, eight were Type 2, and four were Type 3. This study included no cases of Type 4 or 5 lesions. Treatment of all lesions consisted of excision, curettage, and bone grafting with care taken to preserve the growth plate. Adjunctive cauterization was performed in two cases. There were no incidences of postoperative physeal plate arrest. Overgrowth of the fibula occurred in one patient. Three patients experienced recurrent lesions. One of the children underwent repeat curettage and bone grafting with no additional recurrence. In the other two children with recurrence, the lesion had grown away from the physeal plate while remaining static in size and asymptomatic. Based on this study, juxtaphyseal aneurysmal bone cysts may be treated satisfactorily with intralesional surgery and bone grafting with expectation of normal physeal growth.

  1. Association of parity with carotid diameter and distensibility: multi-ethnic study of atherosclerosis.

    PubMed

    Vaidya, Dhananjay; Bennett, Wendy L; Sibley, Christopher T; Polak, Joseph F; Herrington, David M; Ouyang, Pamela

    2014-08-01

    Pregnancy and childbirth are associated with hemodynamic changes and vascular remodeling. It is not known whether parity is associated with later adverse vascular properties such as larger arterial diameter, wall thickness, and lower distensibility. We used baseline data from 3283 women free of cardiovascular disease aged 45 to 84 years enrolled in the population-based Multi-Ethnic Study of Atherosclerosis. Participants self-reported parity status. Ultrasound-derived carotid artery lumen diameters and brachial artery blood pressures were measured at peak-systole and end-diastole. Common carotid intima-media thickness was also measured. Regression models to determine the association of carotid distensibility coefficient, lumen diameter, and carotid intima-media thickness with parity were adjusted for age, race, height, weight, diabetes mellitus, current smoking, blood pressure medication use, and total and high-density lipoprotein cholesterol levels. The prevalence of nulliparity was 18%. In adjusted models, carotid distensibility coefficient was 0.09×10−5 Pa−1 lower (P=0.009) in parous versus nulliparous women. Among parous women, there was a nonlinear association with the greatest carotid distensibility coefficient seen in women with 2 live births and significantly lower distensibility seen in primiparas (P=0.04) or with higher parity >2 (P=0.005). No such pattern of association with parity was found for lumen diameter or carotid intima-media thickness. Parity is associated with lower carotid artery distensibility, suggesting arterial remodeling that lasts beyond childbirth. These long-term effects on the vasculature may explain the association of parity with cardiovascular events later in life.

  2. The 10-year Trend of Periprocedural Complication Following Carotid Artery Stenting; Single Center Experience

    SciTech Connect

    Hong, Jeong-Ho; Kang, Jihoon; Yeo, Min-Ju; Kim, Beom Joon; Jang, Min Uk; Bae, Hee-Joon; Kwon, O-Ki; Hwang, Gyo Jun; Oh, Chang Wan; Jung, Cheolkyu; Lee, Ji Sung; Han, Moon-Ku

    2015-04-15

    PurposeCarotid endarterectomy and stenting are used to treat carotid stenosis, with the volume of carotid artery procedures increasing over the past decade. We investigated the 10-year trend of periprocedural complications with an increasing procedure volume of carotid stenting at a single tertiary hospital.MethodsWe collected 416 consecutive cases (384 patients) of carotid artery stenting performed for either symptomatic (231 cases, 55.5 %) or asymptomatic (185 cases, 44.5 %) internal carotid artery stenosis at a single center. Periprocedural complication was defined as any stroke, myocardial infarction, or death. Procedure-related outcome included any dissection, hemodynamic event, or periprocedural complication.ResultsThe mean age was 68.8 years (82.8 % males; range of 20–89 years); 23.9 % were older than 75 years. Before the procedure, 99.3 and 56.0 % of patients received antiplatelet and lipid-lowering medication, respectively. The overall periprocedural complication rate was 3.6 % (1.6 and 5.2 % in the asymptomatic and symptomatic group, respectively). The composite outcome of any stroke or death was 3.4 %. Periprocedural complication and procedure-related outcome showed a decremental trend with increasing procedure volume, and this trend remained after adjusting for confounders.ConclusionsOur study suggests that carotid stenting at an experienced center might reduce the periprocedural complications. Our periprocedural complication rate of carotid artery stenting may be comparable to, or somewhat lower than, that reported in other clinical trials.

  3. Brachial-Ankle Pulse Wave Velocity is Associated with Composite Carotid and Coronary Atherosclerosis in a Middle-Aged Asymptomatic Population

    PubMed Central

    Joo, Hyung Joon; Cho, Sang-A; Cho, Jae-Young; Lee, Seunghun; Park, Jae Hyoung; Hwang, Sung Ho; Hong, Soon Jun; Yu, Cheol Woong

    2016-01-01

    Aim: Although arterial stiffness has been associated with the development of atherosclerosis, the role of brachial-ankle pulse wave velocity (baPWV) for diagnosing composite coronary and carotid atherosclerosis has not been completely elucidated. Method: We enrolled 773 asymptomatic individuals who were referred from 25 public health centers in Seoul and who underwent carotid ultrasonography and coronary computed tomography. Noninvasive hemodynamic parameters, including baPWV, were also measured. Composite coronary and carotid atherosclerosis was defined as follows: 1) coronary artery calcium (CAC) score ≥ 100, 2) coronary artery stenosis (CAS) ≥ 50% of diameter stenosis, 3) carotid intima medial thickness (CIMT) ≥ 0.9 mm, or 4) presence of carotid artery plaque (CAP). Results: The incidence of composite coronary and carotid atherosclerosis was 28.2%. Coronary atherosclerosis (CAC and CAS) was significantly associated with carotid atherosclerosis (CIMT and CAP). Subjects with higher baPWV (highest quartile) had a higher prevalence of composite coronary and carotid atherosclerosis (p < .001). Although multivariate analysis failed to show baPWV as an independent predictor for composite atherosclerosis, baPWV had moderate diagnostic power to detect a subject with more than two positive subclinical atherosclerosis exams [area under the curve (AUC), 0.692]. Conclusion: baPWV was associated with the composite coronary and carotid atherosclerotic burden in a community-based asymptomatic population. PMID:27251176

  4. Relationship between carotid intima‐media thickness and arterial stiffness in children after Kawasaki disease

    PubMed Central

    Cheung, Y‐f; Wong, S J; Ho, M H K

    2007-01-01

    Background Evidence of premature atherosclerosis and systemic arterial stiffening in patients after Kawasaki disease is accumulating. Aim To test the hypothesis that carotid intima‐media thickness (IMT), a surrogate marker of atherosclerosis, is associated with systemic arterial stiffness in children after Kawasaki disease. Methods A cohort of 72 patients was studied, comprising 26 patients with Kawasaki disease and coronary aneurysms (group I), 24 patients with Kawasaki disease and normal coronary arteries (group II) and 22 healthy age‐matched children (group III). The carotid IMT, carotid artery stiffness index, brachioradial pulse wave velocity (PWV), fasting total cholesterol, high‐density lipoprotein (HDL) cholesterol and low‐density lipoprotein (LDL) cholesterol were determined and compared among the three groups. Results The carotid IMT was related to indices of arterial stiffness, and significant determinants of carotid IMT were identified by multivariate analysis. The mean (standard deviation (SD)) carotid IMT of both group I (0.41 (0.04) mm) and group II (0.39 (0.04) mm) was significantly greater than that of group III (0.36 (0.04) mm; p<0.001 and p = 0.008, respectively). For the entire cohort, carotid IMT correlated positively with LDL cholesterol (r = 0.31, p = 0.009), carotid artery stiffness index (r = 0.40, p = 0.001) and brachioradial PWV (r = 0.28, p = 0.016), but not with age, body mass index, systemic blood pressure, and HDL and total cholesterol. Multiple linear regression analysis identified carotid artery stiffness index (β = 0.25, p = 0.028) and subject grouping (β = −0.39, p = 0.001; model R2 = 0.29) as significant correlates of carotid IMT. Conclusion The increased carotid IMT in children after Kawasaki disease is associated with systemic arterial stiffening. PMID:16820386

  5. Pediatric intracranial aneurysms.

    PubMed

    Tripathy, L N; Singh, S N

    2009-01-01

    The incidence of subarachnoid haemorrhage from intracranial aneurysms in the paediatric age group is extremely rare. Interestingly, occurrence of vasospasm has been reported to be less in comparison to the adults. Both coiling and clipping have been advocated in selected cases. Because of the thinness of the wall of the arteries, utmost care should be taken while handling these arteries during surgery. The overall results of surgery in children have been reported to be better than their adult counterparts. We present four such cases from our own experience. All these children were operated upon, where the solitary aneurysm in each case was clipped and all of them made a good recovery.

  6. Spatial mapping of dynamic cerebral autoregulation by multichannel near-infrared spectroscopy in high-grade carotid artery disease

    NASA Astrophysics Data System (ADS)

    Reinhard, Matthias; Schumacher, F. Konrad; Rutsch, Sebastian; Oeinck, Maximilian; Timmer, Jens; Mader, Irina; Schelter, Björn; Weiller, Cornelius; Kaller, Christoph P.

    2014-09-01

    The exact spatial distribution of impaired cerebral autoregulation in carotid artery disease is unknown. In this pilot study, we present a new approach of multichannel near-infrared spectroscopy (mcNIRS) for noninvasive spatial mapping of dynamic autoregulation in carotid artery disease. In 15 patients with unilateral severe carotid artery stenosis or occlusion, cortical hemodynamics in the bilateral frontal cortex were assessed from changes in oxyhemoglobin concentration using 52-channel NIRS (spatial resolution ˜2 cm). Dynamic autoregulation was graded by the phase shift between respiratory-induced 0.1 Hz oscillations of blood pressure and oxyhemoglobin. Ten of 15 patients showed regular phase values in the expected (patho) physiological range. Five patients had clearly outlying irregular phase values mostly due to artifacts. In patients with a regular phase pattern, a significant side-to-side difference of dynamic autoregulation was observed for the cortical border zone area between the middle and anterior cerebral artery (p<0.05). In conclusion, dynamic cerebral autoregulation can be spatially assessed from slow hemodynamic oscillations with mcNIRS. In high-grade carotid artery disease, cortical dynamic autoregulation is affected mostly in the vascular border zone. Spatial mapping of dynamic autoregulation may serve as a powerful tool for identifying brain regions at specific risks for hemodynamic infarction.

  7. 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)

  8. Successful Treatment of a Ruptured Extracranial Vertebral Artery Aneurysm with Onyx Instillation.

    PubMed

    Kollmann, Dagmar; Kinstner, Christian; Teleky, Katharina; Wressnegger, Alexander; Koppensteiner, Renate; Huk, Ihor; Neumayer, Christoph; Funovics, Martin

    2016-10-01

    The rupture of an extracranial vertebral artery aneurysm has only been rarely described in the literature and treatment options are therefore not standardized. Here we report the successful endovascular repair of a spontaneously ruptured extracranial left vertebral artery aneurysm using Onyx instillation. A 48-year-old woman was transferred to our clinic after having been intubated due to a massive hematoma of the left neck. A contrast-enhanced computed tomography (CT) showed a rupture of the left extracranial vertebral artery. Several issues complicated the therapeutic decision making in this rare case: first, the patient showed multiple aneurysms in CT angiography; therefore a connective tissue disease could not be excluded. Furthermore, as anamnestic work-up revealed that several episodes of postoperative bleeding and open surgery at this anatomic location are rarely performed, risks for postoperative complications were high. Therefore, the patient was hemodynamically stabilized and the ruptured aneurysm was treated in an endovascular approach with Onyx instillation and coil embolization. Complete exclusion of the aneurysm was achieved without periprocedural or neurological complications. Successful repair was confirmed by CT angiography on the first postoperative day as well as 12 months after the intervention. In conclusion, this case shows that endovascular Onyx embolization of ruptured vertebral aneurysms is a save and feasible method.

  9. Spontaneous thrombosis in giant aneurysm of the anterior communicating artery complex in pediatric age: five-year follow-up.

    PubMed

    Gonçalves, Vítor M; Cristino, N; Cunha E Sá, M

    2014-01-01

    Intracranial aneurysms are rare in the pediatric population, especially in infancy, representing less than 1% of all aneurysms. In this age group, they are more frequent at the carotid bifurcation and in the posterior circulation, with a greater number of giant aneurysms and spontaneous aneurysm thrombosis when compared with the adults. They are life-threatening, and, therefore, early investigation, characterization of the lesion, and treatment are essential. The appropriate management depends on the child's condition, aneurysm characteristics, and the experience of a multidisciplinary team. Noninvasive and radiation-free imagiological studies play an important role in the diagnosis and follow-up of these young patients. We present the case of a 3-month-old boy with an intracranial hemorrhage secondary to the rupture of a giant aneurysm of the anterior communicating artery complex, with spontaneous thrombosis, which is a rare situation due to its location. A conservative approach was assumed and noninvasive evolutive imagiological studies revealed a reduction in the thrombosed aneurysm size and no signs of recanalization. The child recovered to his baseline neurological condition and has had no rehemorrhage until 5 years of follow-up.

  10. Treatment of complex intracranial aneurysm: Case report of the simultaneous use of endovascular and microsurgical techniques

    PubMed Central

    Fernandes, Sérgio T.; Alves, Raphael V.; Dória-Netto, Hugo L.; Puglia Júnior, Paulo; Rivau, Fabiano R.; Jory, Maurício

    2016-01-01

    Background: The surgical treatment of complex intracranial aneurysms (CIAs) represents a significant challenge to the skill and expertise of the neurosurgeon. The natural history of complex cerebrovascular lesions is especially unfavorable because of the pressure effect on adjacent areas, the risk of embolism in the presence of intraluminal thrombi, and the possibility of hemorrhage through leakage or rupture of the aneurysm. The surgical strategy must be customized for each case in order to maximize the treatment effectiveness and the safety of the patient. Case Description: A 68-year-old woman presented with a 10-month history of atypical headaches but no other neurological symptoms. Computed tomography scan and digital subtraction angiography revealed an unruptured saccular aneurysm on the M1 segment of the right middle cerebral artery. The lesion was 21 mm in length in its largest diameter and with an undefined neck (extensive involvement of the walls of the afferent vessel). Craniotomy was performed in order to expose the lesion and allow microsurgical dissection of the neck of the aneurysm and its adjacent structures. A balloon catheter was navigated via the internal carotid artery to a position alongside the aneurysm neck. With the balloon fully inflated, the aneurysm was punctured and drained, and a guide clip was located at the neck of the aneurysm. Additional clips were applied using a similar procedure to ensure the exclusion of the aneurysm. Conclusion: The patient recovered without complications and complete occlusion of the CIA was confirmed on follow-up angiography. A modified Rankin score of 0 was attributed to the patient 6 months after treatment. A multidisciplinary perspective is important in planning and executing the treatment of CIAs. PMID:28144484

  11. Carotid Disease Management: Surgery, Stenting, or Medication.

    PubMed

    Khandelwal, Priyank; Chaturvedi, Seemant

    2015-09-01

    Internal carotid artery stenosis accounts for about 7-10 % of ischemic strokes. Conventional risk factors such as aging, hypertension, diabetes mellitus, and smoking increase the risk for carotid atherosclerosis. All patients with carotid stenosis should receive aggressive medical therapy. Carotid revascularization with either endarterectomy or stenting can benefit select patients with severe stenosis. New clinical trials will examine the contemporary role of carotid revascularization relative to optimal medical therapy.

  12. A comparison of estimation methods for computational fluid dynamics outflow boundary conditions using patient-specific carotid artery.

    PubMed

    Lee, Chang-Joon; Uemiya, Nahoko; Ishihara, Shoichiro; Zhang, Yu; Qian, Yi

    2013-06-01

    Computational fluid dynamics simulations can provide important hemodynamic insights for investigating the effectiveness of carotid artery stenting, but its accuracy is dependent on the boundary conditions such as the outflow pressure, which is difficult to obtain by measurements. Many computational fluid dynamics simulations assume that the outflow pressure is constant (P = 0), but this method is likely to produce different results compared to clinical measurements. We have developed an alternative estimation method called the minimum energy loss method based on the concept of energy loss minimization at flow bifurcation. This new method has been tested on computational fluid dynamics simulation of two patients treated with carotid artery stenting, and its flow ratio at internal carotid artery and wall shear stress distribution was compared with the constant zero outlet pressure method. Three different procedure stages (prestent, poststent, and follow-up) were analyzed. The internal carotid artery flow ratio using the minimum energy loss method generally matched well with ultrasound measurements, but the internal carotid artery flow ratio based on zero outlet pressure method showed a large difference. Wall shear stress distributions varied between methods in response to the change in internal carotid artery flow rate. This study demonstrates the importance of accurate outlet boundary condition for assessing the long-term efficacy of carotid artery stenting and the risk of restenosis in treated patients.

  13. ED 02-3 CLINICAL IMPLICATIONS OF CENTRAL HEMODYNAMICS ON AORTIC AND END-ORGAN DISEASES.

    PubMed

    Hashimoto, Junichiro

    2016-09-01

    The central aorta constitutes the main trunk of the systemic arterial tree. It dilates passively with cardiac ejection during systole and then constricts with its recoil function during diastole, thereby regulating blood pressure and blood flow. The central pulsatile hemodynamics affects local hemodynamics within as well as downstream of the aorta (e.g., end organs).The aorta progressively stiffens and dilates with advancing age, and such age-dependent change is accelerated by hypertension. According to the law of Laplace, wall stress depends on the diameter and pressure of the blood vessel. This has been confirmed by substantial studies which have associated baseline aortic diameter with subsequent development of aortic dissection and progressive dilatation of aortic lumen. This law can also imply potential importance of local pressure within the aorta (i.e., the central pressure) in predicting the development and progression of aortic aneurysms.Several previous studies have shown that hypertension (together with age and obesity) is related to dilatation of the proximal ascending aorta (rather than of the aortic root). In addition, aortic blood flow abnormality may also be importantly related to aortic dilatation because of strong positive association between the diastole flow reversal and lumen diameter in the proximal thoracic aorta. As for the abdominal (infrarenal) aorta, aneurysmal development and progression have been attributed to aortic segmental stiffening (of the bifurcational versus infrarenal segment) and aortic pressure elevation, respectively.Central pulsatile pressure not only represents aortic wall stress but also determines cardiac afterload and microvascular wall stress in the brain and kidney. Central pulsatile flow (in both directions) could also affect the flow distribution into the upper and lower parts of the body and control end-organ function. Aortic structural change (including segmental stiffening and aneurysmal formation) causes central

  14. [Carotid endarterectomy under local anesthesia].

    PubMed

    Kuz'min, A L; Belov, Iu V

    2001-01-01

    Results of carotid endarterectomy (CEAE) in 193 patients with different degree of cerebrovascular insufficiency were analyzed. All the patients were men with carotid atherosclerosis (age from 39 to 68 years, mean age 53.6 +/- 0.4). A total of 253 CEAEs were performed under local anesthesia (60 patients underwent consecutive bilateral operations). In early postoperative period 3 patients died, one of them--of ischemic stroke due to thrombosis of internal carotid artery on the side of the operation. Non-fatal stroke was in 1 patient. There were no intraoperative cerebral complications. This testifies to reliability of cerebral circulation control through direct contact with patient.

  15. Carotid body disease and the physician--chronic carotid glomitis.

    PubMed Central

    Heath, D.; Khan, Q.; Nash, J.; Smith, P.

    1989-01-01

    There are three types of histological change in the carotid bodies which appear to have physiological and clinical associations. A prominence of the dark variant of chief cells with their contents of met-enkephalin and other peptides appears to be associated with acute exposure to hypoxia. Proliferation of sustentacular cells around the clusters of chief cells appears to be related to ageing and also to systemic hypertension. Recently we have described a new condition of chronic carotid glomitis which is characterized by follicles of lymphocytes and may have a basis in auto-immunity. In the present review we report for the first time plasma cell activity in the carotid bodies of an elderly man, especially around nerve fibrils and unmyelinated axons ensheathed in sustentacular cells. Such appearances are consistent with the view that ageing nerve fibrils may be the antigenic stimulus for the development of chronic carotid glomitis. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:2692011

  16. Endoscopic endonasal management of cerebrospinal fluid rhinorrhea after anterior clinoidectomy for aneurysm surgery: changing the paradigm of complication management.

    PubMed

    Beer-Furlan, Andre; Balsalobre, Leonardo; Vellutini, Eduardo de Arnaldo Silva; Stamm, Aldo Cassol; Pahl, Felix Hendrik; Gentil, Andre Felix

    2016-07-01

    Resection of the anterior clinoid process results in the creation of the clinoid space, an important surgical step in the exposure and clipping of clinoidal and supraclinoidal internal carotid artery aneurysms. Cerebrospinal fluid rhinorrhea is an undesired and potentially serious complication. Conservative measures may be unsuccesful, and there is no consensus on the most appropriate surgical treatment. Two patients with persistent transclinoidal CSF rhinorrhea after aneurysm surgery were successfully treated with a combined endoscopic transnasal/transeptal binostril approach using a fat graft and ipsilateral mucosal nasal septal flap. Anatomical considerations and details of the surgical technique employed are discussed, and a management plan is proposed.

  17. Pancreaticoduodenal arterial aneurysms.

    PubMed Central

    Verta, M J; Dean, R H; Yao, J S; Conn, J; Mehn, W H; Bergan, J J

    1977-01-01

    Experience with four aneurysms of the pancreaticoduodenal artery is reviewed and compared to the reported experience of 19 other cases. In view of the common presentation of such lesions as intra-abdominal hemorrhage preceded by non-specific abdominal pain and other digestive symptoms, it is suggested that angiography perfomed preoperatively or intraoperatively allows definitive diagnosis and leads to specific therapy. PMID:406863

  18. Preclinical evaluation of RYM1, a novel MMP-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; Jung, Jae-Joon; Sadeghi, Mehran

    2017-03-30

    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, based on 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 Tc-99m. 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 CaCl2-induced carotid aneurysm (n = 11). Angiotensin II (Ang II)-infused apoE-/- (n = 16) were used for micro-single-photon emission computed tomography (SPECT)/computed tomography (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 hours, and demonstrated rapid renal clearance and lower blood levels in vivo compared to (99m)Tc-RP805. (99m)Tc-RYM1 binding to aneurysm and its specificity were shown by autoradiography in carotid aneurysm. Ang II infusion in apoE-/- mice for 4 weeks resulted in AAA formation in 36 % (4/11) of surviving animals. In vivo

  19. Aneurysms of Hemodialysis Access Grafts: Treatment with Covered Stents: A Report of Three Cases

    SciTech Connect

    Hausegger, Klaus A.; Tiessenhausen, Kurt; Klimpfinger, Martin; Raith, Johann; Hauser, Hubert; Tauss, Josef

    1998-07-15

    Three patients with dialysis access graft shunts, having a symptomatic pseudoaneurysm and a hemodynamically significant stenosis at the anastomosis between the graft shunt and the subclavian vein, were treated with percutaneous transluminal angioplasty and insertion of a Wallstent. Pseudoaneurysms were excluded by percutaneous insertion of a Cragg Endo-Pro stent-graft with a diameter of 6 mm and a length of 6-10 cm. All three aneurysms were excluded successfully. In two patients, the stent-graft was punctured repeatedly during follow-up and the aneurysms recurred after 7 and 8 months, respectively. The patency of the dialysis shunt after stent-graft insertion was 8 (n= 1) and 9 months (n= 2). Due to the recurrence of the aneurysm (n= 2) or recurrent thrombosis (n= 1) the use of these shunts was discontinued.

  20. Brainstem Hemorrhage Caused by Direct Carotid-Cavernous Fistula

    PubMed Central

    Chan, Fook-How; Shen, Chao-Yu; Liu, Jung-Tung; Li, Cho-Shun

    2014-01-01

    Summary A 34-year-old woman presented with a history of persisting headache for years, and a newly developed dizziness, left facial palsy and right hemiparesis two days prior to this admission. Initial computed tomographic angiography of the head demonstrated an area of increased density in the left middle and posterior fossae. Multiple aneurysmally dilated venous ectasias with contrast enhancement at the left pre-pontine cistern causing a massive mass effect to the brainstem were also noted, suggesting a huge vascular abnormality. Digital subtraction angiography revealed an abnormal vascular lesion surrounding the brainstem, which indicated a left direct carotid-cavernous fistula with posterior drainage. As her consciousness deteriorated the next day, a follow-up computed tomography scan was done which revealed a pontine hemorrhage. Subsequently, endovascular closure of the fistula with sacrifice of the left ICA was performed, which successfully eliminated the imaging abnormalities. PMID:25207913

  1. 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

    2017-02-24

    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

  2. Mid-term and long-term follow-up of intracranial aneurysms treated by the p64