Vaginal dilator therapy for women receiving pelvic radiotherapy.

PubMed

Miles, Tracie; Johnson, Nick

2014-09-08

Vaginal dilation therapy is advocated after pelvic radiotherapy to prevent stenosis (abnormal narrowing of the vagina), but can be uncomfortable and psychologically distressing. To assess the benefits and harms of different types of vaginal dilation methods offered to women treated by pelvic radiotherapy for cancer. Searches included the Cochrane Central Register of Controlled Trials (CENTRAL 2013, Issue 5), MEDLINE (1950 to June week 2, 2013), EMBASE (1980 to 2013 week 24) and CINAHL (1982 to 2013). Comparative data of any type, which evaluated dilation or penetration of the vagina after pelvic radiotherapy treatment for cancer. Two review authors independently assessed whether potentially relevant studies met the inclusion criteria. We found no trials and therefore analysed no data. We identified no studies for inclusion in the original review or for this update. However, we felt that some studies that were excluded warranted discussion. These included one randomised trial (RCT), which showed no improvement in sexual scores associated with encouraging women to practise dilation therapy; a recent small RCT that did not show any advantage to dilation over vibration therapy during radiotherapy; two non-randomised comparative studies; and five correlation studies. One of these showed that objective measurements of vaginal elasticity and length were not linked to dilation during radiotherapy, but the study lacked power. One study showed that women who dilated tolerated a larger dilator, but the risk of objectivity and bias with historical controls was high. Another study showed that the vaginal measurements increased in length by a mean of 3 cm after dilation was introduced 6 to 10 weeks after radiotherapy, but there was no control group; another case series showed the opposite. Three recent studies showed less stenosis associated with prophylactic dilation after radiotherapy. One small case series suggested that dilation years after radiotherapy might restore the vagina to a functional length. There is no reliable evidence to show that routine, regular vaginal dilation during radiotherapy treatment prevents stenosis or improves quality of life. Several observational studies have examined the effect of dilation therapy after radiotherapy. They suggest that frequent dilation practice is associated with lower rates of self reported stenosis. This could be because dilation is effective or because women with a healthy vagina are more likely to comply with dilation therapy instructions compared to women with strictures. We would normally suggest that a RCT is needed to distinguish between a casual and causative link, but pilot studies highlight many reasons why RCT methodology is challenging in this area.

Treatment of oropharyngeal dysphagia secondary to idiopathic cricopharyngeal bar: Surgical cricopharyngeal muscle myotomy versus dilation.

PubMed

Marston, Alexander P; Maldonado, Francisco J; Ravi, Karthik; Kasperbauer, Jan L; Ekbom, Dale C

To compare swallowing outcomes following cricopharyngeal (CP) dilation versus surgical myotomy in patients with dysphagia secondary to idiopathic CP bar. All patients had an idiopathic CP bar without a history of Zenker's diverticulum, head and neck cancer, or systemic neurologic disease treated between 2000 and 2013. The Functional Outcome Swallowing Scale (FOSS) was utilized to assess dysphagia symptoms. Twenty-three patients underwent 46 dilations and 20 patients had a myotomy. Nineteen of 23 (83%) patients in the dilation group and all patients in the myotomy group reported improved swallow function. The median difference in pre- versus post-intervention FOSS scores was not statistically significant (p=0.07) between the dilation and myotomy groups with mean reductions of 1.3 and 1.8, respectively. Seventeen of 23 (74%) dilation patients had persistent or recurrent dysphagia with 13 (57%) requiring repeat dilation and 4 (17%) undergoing CP myotomy. The median time to first reintervention in the dilation group was 13.6months. Nineteen of 20 (95%) surgical myotomy patients did not experience recurrent dysphagia. Both endoscopic CP dilation and myotomy led to similar initial improvement in swallow function for patients with primary idiopathic CP bar; however, dilation is more likely to provide temporary benefit. Copyright © 2016 Elsevier Inc. All rights reserved.

Temporal evolution of intraocular pressure elevation after pupillary dilation in pigment dispersion syndrome.

PubMed

Jewelewicz, Daniel A; Radcliffe, Nathan M; Liebmann, Jeffrey; Ritch, Robert

2009-03-01

To report 4 patients with pigment dispersion syndrome (PDS) who had delayed intraocular pressure (IOP) spikes after pharmacologic pupillary dilation. Four patients with a diagnosis of PDS with documented IOP spike after pharmacologic pupillary dilation were included. Study patients were examined before and after pupillary dilation. The amount of pigment present in the anterior chamber and the IOP were measured at hourly intervals. Although maximal pigment liberation occurred immediately after maximal dilation, the IOP continued to elevate for at least 1.5 hours. The increase in IOP after pupillary dilation may not occur simultaneously with maximal pigment liberation but may follow it after the pigment has settled out of the anterior chamber. This has implications for monitoring patients with PDS after dilation to detect and treat rises in IOP.

Treatment of benign esophageal stricture by Eder-Puestow or balloon dilators: a comparison between randomized and prospective nonrandomized trials.

PubMed

Yamamoto, H; Hughes, R W; Schroeder, K W; Viggiano, T R; DiMagno, E P

1992-03-01

To determine whether the natural history of strictures is affected by the type of dilator used to treat newly diagnosed peptic strictures, we designed a prospective randomized trial to compare the results after Eder-Puestow or Medi-Tech balloon dilation. We entered 31 patients into the trial. We also prospectively followed up all 92 nonrandomized patients who underwent their first dilation for a benign stricture during the same period as the prospective randomized trial. The nonrandomized patients also underwent dilation with either the Eder-Puestow or the balloon technique at the discretion of the gastroenterologist performing the endoscopy. We found no statistically significant differences in the immediate or long-term results of the two methods among the randomized, nonrandomized, and overall combined groups. All but 1 of the 123 patients had immediate relief of dysphagia. Within each group of patients, the probability of remaining free of dysphagia 1 year after the initial dilation was approximately 20%, and the probability of not requiring a second dilation was approximately 65% with either technique. Major (esophageal rupture) and minor (bleeding or chest pain) complications occurred in 1% and 5% of the patients and 0.4% and 3% of the total dilation procedures, respectively. The esophageal rupture and four of six minor complications occurred after repeated dilations. Five of the six minor complications occurred with use of the Eder-Puestow dilators. We conclude that Eder-Puestow and balloon dilations of benign esophageal strictures are associated with similar outcomes, but repeated dilations and the Eder-Puestow technique may be associated with an increased risk of complications.

Cervical Dilatation Curves of Spontaneous Deliveries in Pregnant Japanese Females

PubMed Central

Inde, Yusuke; Nakai, Akihito; Sekiguchi, Atsuko; Hayashi, Masako; Takeshita, Toshiyuki

2018-01-01

Background: Although cervical dilatation curves are crucial for appropriate management of labor progression, abnormal labor progression and obstetric interventions were included in previous and widely-used cervical dilatation curves. We aimed to describe the cervical dilatation curves of normal labor progression in pregnant Japanese females without abnormal labor progression and obstetric interventions. Methods: We completed retrospective obstetric record reviews on 3172 pregnant Japanese females (parity = 0, n = 1047; parity = 1, n = 1083; parity ≥ 2, n = 1042), aged 20 to 39 years old at delivery, with pregravid body mass indices of less than 30. All patients underwent spontaneous deliveries with term, singleton, cephalic and live newborns of appropriate-for-gestational age birthweight, without adverse neonatal outcomes. We characterized labor progression patterns by examining the relationship between elapsed times from the full dilatation and cervical dilatation stages, and labor durations by examining the distribution of time intervals from one cervical dilatation stage, to the next, and ultimately to the full dilatation. Results: Fastest cervical changes occurred at 6 cm (primiparas) and 5 cm (multiparas) of dilatation. The 95%tile of labor progression took over 3 hours to progress from 6 cm to 7 cm (primiparas), and over 2 hours to progress from 5 cm to 6 cm (multiparas). The 5%tile of traverse time to the full dilatation, during the active phase, was less than 1 hour (primiparas) and 0.5 hours (multiparas). At the end of the active phase, no deceleration phase was observed. Conclusions: Active labor may not start until 5 cm of dilatation. At the beginning of the active phase, cervical dilatation was slower than previously described. These results may reduce opportunities for obstetric interventions during labor progression. PMID:29725244

Dilation or biodegradable stent placement for recurrent benign esophageal strictures: a randomized controlled trial.

PubMed

Walter, Daisy; van den Berg, Maarten W; Hirdes, Meike M; Vleggaar, Frank P; Repici, Alessandro; Deprez, Pierre H; Viedma, Bartolomé L; Lovat, Laurence B; Weusten, Bas L; Bisschops, Raf; Haidry, Rehan; Ferrara, Elisa; Sanborn, Keith J; O'Leary, Erin E; van Hooft, Jeanin E; Siersema, Peter D

2018-06-08

 Dilation is the standard of care for recurrent benign esophageal strictures (BES). Biodegradable stents may prolong the effect of dilation and reduce recurrences. Efficacy and safety of dilation and biodegradable stent placement early in the treatment algorithm of recurrent BES were compared.  This multicenter, randomized study enrolled patients with BES treated with previous dilations to ≥ 16 mm. The primary end point was number of repeat endoscopic dilations for recurrent stricture within 3 and 6 months. Secondary outcomes through 12 months included safety, time to first dilation for recurrent stricture, dysphagia, and level of activity.  At 3 months, the biodegradable stent group (n = 32) underwent significantly fewer endoscopic dilations for recurrent stricture compared with the dilation group (n = 34; P  < 0.001). By 6 months, the groups were similar. The number of patients experiencing adverse events was similar between the groups. Two patients in the biodegradable stent group died after developing tracheoesophageal fistulas at 95 and 96 days post-placement; no deaths were attributed to the stent. Median time to first dilation of recurrent stricture for the biodegradable stent group was significantly longer (106 vs. 41.5 days; P  = 0.003). Dysphagia scores improved for both groups. Patients in the biodegradable stent group had a significantly higher level of activity through 12 months ( P  < 0.001).  Biodegradable stent placement is associated with temporary reduction in number of repeat dilations and prolonged time to recurrent dysphagia compared with dilation. Additional studies are needed to better define the exact role of biodegradable stent placement to treat recurrent BES. © Georg Thieme Verlag KG Stuttgart · New York.

Effect of pupillary dilatation on glaucoma assessments using optical coherence tomography

PubMed Central

Smith, Michael; Frost, Andrew; Graham, Christopher Mark; Shaw, Steven

2007-01-01

Aims To examine the effect of pupillary dilatation on the reliability of retinal nerve fibre layer (RNFL) and optic nerve head (ONH) assessments using Stratus OCT in a glaucoma clinic. Methods Observational study of 38 patients attending a glaucoma clinic. The “fast optic disc” and “fast RNFL thickness” programs on Stratus OCT were used to measure the RNFL thickness and ONH cup to disc ratio (CDR). Two scans were done before dilatation and two after dilatation with tropicamide 1% drops. The mean values and reproducibility before and after dilatation were compared, along with the quality of scans as indicated by the “signal strength” score. Results In nine patients (23.7%) no images were obtained undilated but after dilatation examination was possible in all patients. Inability to obtain an undilated scan was associated with smaller pupil size and increasing cataract. The scan quality, as judged by the signal strength score, was higher dilated than undilated for both RNFL thickness (p = 0.011) and ONH CDR (p = 0.007). Reproducibility was higher with dilated scans for RNFL thickness but not for ONH CDR. There were significant differences between the dilated and undilated examinations for three of the five RNFL thickness variables and two of the three ONH CDR categories. Conclusions Acquisition of high quality OCT images was not possible without pupillary dilatation in about 25% of the patients. The dilated scans were more reproducible and of higher quality than the undilated scans. The two methods of examination do not appear to be interchangeable, suggesting that in follow up examinations the pupil should be in the same condition as at baseline. Pupillary dilatation is recommended before glaucoma assessments using Stratus OCT. PMID:17556429

Application of Electrocautery Needle Knife Combined with Balloon Dilatation versus Balloon Dilatation in the Treatment of Tracheal Fibrotic Scar Stenosis.

PubMed

Bo, Liyan; Li, Congcong; Chen, Min; Mu, Deguang; Jin, Faguang

Electrocautery needle knives can largely reduce scar and granulation tissue hyperplasia and play an important role in treating patients with benign stricture. The aim of this retrospective study was to evaluate the efficacy and safety of electrocautery needle knife combined with balloon dilatation versus balloon dilatation alone in the treatment of tracheal stenosis caused by tracheal intubation or tracheotomy. We retrospectively analysed the clinical data of 43 patients with tracheal stenosis caused by tracheotomy or tracheal intubation in our department from January 2013 to January 2016. Among these 43 patients, 23 had simple web-like stenosis and 20 had complex steno sis. All patients were treated under general anaesthesia, and the treatment methods were (1) balloon dilatation alone, (2) needle knife excision of fibrotic tissue combined with balloon dilatation, and (3) needle knife radial incision of fibrotic tissue combined with balloon dilatation. After treatment the symptoms, such as shortness of breath, were markedly improved immediately in all cases. The stenosis degree of patients who were treated with the elec-trocautery needle knife combined with balloon dilatation had better improvement compared with that of those treated with balloon dilatation treatment alone after 3 months (0.45 ± 0.04 vs. 0.67 ± 0.05, p < 0.01), and the proportion of restenosis occurrence that required further treatment was decreased at 6 months (46.9 vs. 81.8%), especially for the web-like stenosis patients, as most of their stenoses dilated with no obvious restenosis and achieved clinical cure. Electrocautery needle knife combined with balloon dilatation is an effective and safe treatment for tracheal fibrotic stenosis compared with balloon dilatation alone. © 2017 S. Karger AG, Basel.

Office-based esophageal dilation in head and neck cancer: Safety, feasibility, and cost analysis.

PubMed

Howell, Rebecca J; Schopper, Melissa A; Giliberto, John Paul; Collar, Ryan M; Khosla, Sid M

2018-02-08

To review experience, safety, and cost of office-based esophageal dilation in patients with history of head and neck cancer (HNCA). The medical records of patients undergoing esophageal dilation in the office were retrospectively reviewed between August 2015 and May 2017. Patients were given nasal topical anesthesia. Next, a transnasal esophagoscopy (TNE) was performed. If the patient tolerated TNE, we proceeded with esophageal dilation using Seldinger technique with the CRE™ Boston Scientific (Boston Scientific Corp., Marlborough, MA) balloon system. Patients were discharged directly from the outpatient clinic. Forty-seven dilations were performed in 22 patients with an average of 2.1 dilations/patient (range 1-10, standard deviation [SD] ± 2.2). Seventeen patients (77%) were male. The average age was 67 years (range 35-78 years, SD ± 8.5). The most common primary site of cancer was oral cavity/oropharynx (n = 10), followed by larynx (n = 6). All patients (100%) had history of radiation treatment. Four patients were postlaryngectomy. The indication for esophageal dilation was esophageal stricture and progressive dysphagia. All dilations occurred in the proximal esophagus. There were no major complications. Three focal, superficial lacerations occurred. Two patients experienced mild, self-limited epistaxis. One dilation was poorly tolerated due to discomfort. One patient required pain medication postprocedure. Office-based esophageal dilation generated $15,000 less in health system charges compared to traditional operating room dilation on average per episode of care. In patients with history of HNCA and radiation, office-based TNE with esophageal dilation appears safe, well-tolerated, and cost-effective. In a small cohort, the technique has low complication rate and is feasible in an otolaryngology outpatient office setting. 4. Laryngoscope, 2018. © 2018 The American Laryngological, Rhinological and Otological Society, Inc.

Pneumomediastinum after self-dilation of the esophagus.

PubMed

Noppen, M M; Corne, L; Peters, O; Smekens, L; Musch, W; Vincken, W

1987-10-01

Pneumomediastinum following esophageal perforation is a known complication of Eder Puestow dilation for esophageal stenosis. This is the first reported case of esophageal perforation and pneumomediastinum occurring after instrumental self-dilation of a stenotic esophageal lesion. The observed 0.02 percent perforation rate in this patient (compared to the reported 0.3 percent in Eder Puestow "hetero"-dilation) makes the Eder Puestow auto-dilation procedure seem justifiable in a well-trained and well-informed patient.

Contribution of Different Anatomical and Physiologic Factors to Iris Contour and Anterior Chamber Angle Changes During Pupil Dilation: Theoretical Analysis

PubMed Central

Jouzdani, Sara; Amini, Rouzbeh; Barocas, Victor H.

2013-01-01

Purpose. To investigate the contribution of three anatomical and physiologic factors (dilator thickness, dynamic pupillary block, and iris compressibility) to changes in iris configuration and anterior chamber angle during pupil dilation. Methods. A mathematical model of the anterior segment based on the average values of ocular dimensions was developed to simulate pupil dilation. To change the pupil diameter from 3.0 to 5.4 mm in 10 seconds, active dilator contraction was applied by imposing stress in the dilator region. Three sets of parameters were varied in the simulations: (1) a thin (4 μm, 1% of full thickness) versus a thick dilator (covering the full thickness iris) to quantify the effects of dilator anatomy, (2) in the presence (+PB) versus absence of pupillary block (−PB) to quantify the effect of dynamic motion of aqueous humor from the posterior to the anterior chamber, and (3) a compressible versus an incompressible iris to quantify the effects of iris volume change. Changes in the apparent iris–lens contact and angle open distance (AOD500) were calculated for each case. Results. The thin case predicted a significant increase (average 700%) in iris curvature compared with the thick case (average 70%), showing that the anatomy of dilator plays an important role in iris deformation during dilation. In the presence of pupillary block (+PB), AOD500 decreased 25% and 36% for the compressible and incompressible iris, respectively. Conclusions. Iris bowing during dilation was driven primarily by posterior location of the dilator muscle and by dynamic pupillary block, but the effect of pupillary block was not as large as that of the dilator anatomy according to the quantified values of AOD500. Incompressibility of the iris, in contrast, had a relatively small effect on iris curvature but a large effect on AOD500; thus, we conclude that all three effects are important. PMID:23482467

Pupil Dilation to Explicit and Non-Explicit Sexual Stimuli.

PubMed

Watts, Tuesday M; Holmes, Luke; Savin-Williams, Ritch C; Rieger, Gerulf

2017-01-01

Pupil dilation to explicit sexual stimuli (footage of naked and aroused men or women) can elicit sex and sexual orientation differences in sexual response. If similar patterns were replicated with non-explicit sexual stimuli (footage of dressed men and women), then pupil dilation could be indicative of automatic sexual response in fully noninvasive designs. We examined this in 325 men and women with varied sexual orientations to determine whether dilation patterns to non-explicit sexual stimuli resembled those to explicit sexual stimuli depicting the same sex or other sex. Sexual orientation differences in pupil dilation to non-explicit sexual stimuli mirrored those to explicit sexual stimuli. However, the relationship of dilation to non-explicit sexual stimuli with dilation to corresponding explicit sexual stimuli was modest, and effect magnitudes were smaller with non-explicit sexual stimuli than explicit sexual stimuli. The prediction that sexual orientation differences in pupil dilation are larger in men than in women was confirmed with explicit sexual stimuli but not with non-explicit sexual stimuli.

Malignant Esophagogastric Junction Obstruction: Efficacy of Balloon Dilation Combined with Chemotherapy and/or Radiation Therapy

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

Ko, Gi-Young; Song, Ho-Young, E-mail: hysong@amc.seoul.kr; Hong, Heuk-Jin

2003-04-15

Purpose: To assess the efficacy of balloon dilation combined with chemotherapy and/or radiation therapy for palliation of dysphagia due to malignant esophagogastric junction strictures. Methods: Fluoroscopically guided balloon dilation was attempted in 20 patients. The causes of strictures were gastric adenocarcinoma (n = 10) and esophageal squamous cell carcinoma (n = 10). Scheduled chemotherapy and/or radiation therapy followed balloon dilation in all patients. Results: There were no technical failures or major complications. After balloon dilation, 15 (75%) patients showed improvement of dysphagia. No patient complained of reflux esophagitis during the follow-up period. Among the 15 patients, seven needed no furthermore » treatment for palliation of dysphagia until their deaths. The remaining eight patients underwent repeat balloon dilation(n = 4) or stent placement (n = 4)3-43 weeks (mean 15 weeks) after the initial balloon dilation because of recurrent dysphagia. Conclusion: Balloon dilation combined with chemotherapy and/or radiation therapy seems to be an easy and reasonably effective palliative treatment for malignant esophagogastric strictures.« less

A prosthesis for banding the main pulmonary artery, capable of serial dilatation by balloon angioplasty.

PubMed

Vince, D J; Culham, J A

1989-03-01

A prosthesis constructed with a fatigued steel helix encased in a silicone rubber shield was used to band the main pulmonary artery in 10 dogs. After a mean duration of 138 days the banded site was dilated with a 20 mm diameter angioplasty catheter. This dilatation produced a mean increase of 44.3% in the cross-sectional area. A further mean increase of 2.2% in the cross-sectional area was measured 137 days after the dilatation. In five uncomplicated experiments a second dilatation was performed with a 23 mm diameter angioplasty catheter after a mean interval of 140 days. The second dilatation produced a further 21% increase in the cross-sectional area. In the five experiments in which two dilatations were performed, there was a total increase in the mean cross-sectional area of 94% produced 273 days after banding. This prosthesis maintains banding of the main pulmonary artery and can be serially dilated by balloon angioplasty.

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

Lee, Woong Hee; Kim, Jin Hyoung, E-mail: m1fenew@daum.net; Park, Jung-Hun

Purpose: Little was known about the safety and long-term efficacy of fluoroscopically guided balloon dilation for postintubation tracheal stenosis. The purpose of this study was to evaluate the safety and long-term efficacy of fluoroscopically guided balloon dilation in patients with postintubation tracheal stenosis. Methods: From February 2000 to November 2010, 14 patients underwent fluoroscopically guided balloon dilation for postintubation tracheal stenosis. Technical success, clinical success, and complications were evaluated. Patients were followed up for recurrent symptoms. Results: In all patients, fluoroscopically guided balloon dilation was technically and clinically successful with no major complications. Following the initial procedure, six patients (43more » %) remained asymptomatic during a follow-up period. Obstructive symptoms recurred in eight patients (57 %) within 6 months (mean, 1.7 months), who were treated with repeat balloon dilation (n = 4) and other therapies. Of the four patients who underwent repeat balloon dilation, three became asymptomatic. One patient became asymptomatic after a third balloon dilation. On long-term (mean, 74 months) follow-up, 71 % of patients experienced relief of symptoms following fluoroscopically guided balloon dilation. Conclusions: Fluoroscopically guided balloon dilation may be safe, is easy to perform, and resulted in effective treatment in patients with postintubation tracheal stenosis.« less

Dilatation of aortic grafts over time: what to expect and when to be concerned.

PubMed

Schroeder, Torben V; Eldrup, Nikolaj; Just, Sven; Hansen, Marc; Nyhuus, Bo; Sillesen, Henrik

2009-06-01

Dilatation of aortic prosthetic grafts is commonly reported, but most reports are anecdotal, with little objective data in the literature. We performed a prospective trial of 303 patients who underwent prosthetic graft repair for aortic aneurysm or occlusive disease, randomizing patients between insertion of a woven polyester or expanded polytetrafluoroethylene (ePTFE) graft. Patients were followed with computed tomography and ultrasonography for up to 5 years in order to assess the frequency and magnitude of postoperative dilatation. Graft dilatation was documented in patients with polyester grafts at 12 months. Thereafter and up to 60 months, polyester grafts did not dilate further. After 5 years, polyester prostheses had dilated by 25% and ePTFE by 12.5%, as determined by computed tomography imaging. These observations suggest that dilatation of prosthetic grafts is more frequent with knitted polyester grafts compared with ePTFE. Dilatation occurs within the first year after implantation and can be, in part, explained by a discrepancy between the initial nominal graft diameter and its diameter after clamp release, probably due to an in vivo adaptation of the textile structure. Interestingly, graft dilatation did not appear to be associated with an increased frequency of graft-related complications.

Psoriasis and dilated cardiomyopathy: coincidence or associated diseases?

PubMed

Eliakim-Raz, Noa; Shuvy, Mony; Lotan, Chaim; Planer, David

2008-01-01

Psoriasis is a common immune-mediated disease which affects 1-3% of the population. The etiology of psoriasis is unknown. Idiopathic dilated cardiomyopathy is probably the end result of a variety of toxic, metabolic or infectious agents. During a computerized search for cardiomyopathy among all patients hospitalized with psoriasis in the Hadassah University Hospital since 1980 we found an increased prevalence of cardiomyopathy, and specifically dilated cardiomyopathy. We present 4 patients who suffer from both conditions. In accordance with previous data, an association between preexisting psoriasis and dilated cardiomyopathy is suggested. We suggest that the genetic risk factors of dilated cardiomyopathy are shared by psoriasis, and more specifically psoriatic arthritis. Alternatively, the immune reaction that is triggered in dilated cardiomyopathy leading to the progression of the disease might be enhanced in patients with psoriasis or psoriatic arthritis. Chronic inflammation and persistent secretion of proinflammatory cytokines may be considered a potential pathway, triggering the initiation and progression of dilated cardiomyopathy in psoriatic patients. Further investigation of the genetic and immune risk factors involved in dilated cardiomyopathy and in psoriasis may lead to a better understanding of the pathogenesis and treatment of dilated cardiomyopathy. Copyright 2008 S. Karger AG, Basel.

Fluoroscopically guided large balloon dilatation for treating congenital esophageal stenosis in children.

PubMed

Hu, Hong-Tao; Shin, Ji Hoon; Kim, Jin-Hyoung; Jang, Jong Keon; Park, Jung-Hoon; Kim, Tae-Hyung; Nam, Deok Ho; Song, Ho-Young

2015-07-01

We aimed to evaluate the safety and clinical effectiveness of fluoroscopically guided large balloon dilatation for treating congenital esophageal stenosis in children. Our study included seven children (mean age 4.0 years) who underwent a total of ten balloon dilatation sessions. The initial balloon diameters were 10-15 mm. The technical success, clinical success (improved food intake and reduced dysphagia within 1 month following the first balloon dilatation), dysphagia recurrence, and complications were retrospectively evaluated. Technical and clinical success rates were 100 %. During the mean 38-month follow-up period after the first balloon dilatation, 3 (43 %) patients underwent only one additional balloon dilatation 4-5 months after the first balloon dilatation for dysphagia recurrence. Two of them showed improvement without further recurrence, while the remaining one underwent partial esophagectomy. Well-contained transmural esophageal rupture (type 2) occurred in two (29 %, 2/7) patients and during two (20 %, 2/10) balloon dilatation sessions. All ruptures were successfully treated conservatively. Our study showed that fluoroscopically guided large balloon dilatation seems to be a simple and effective primary treatment technique for congenital esophageal stenosis in children. Esophageal ruptures were not uncommon although they were not fatal.

Sonographic evaluation of the bladder neck in continent and stress-incontinent women.

PubMed

Schaer, G N; Perucchini, D; Munz, E; Peschers, U; Koechli, O R; Delancey, J O

1999-03-01

To evaluate a new sonographic method to measure depth and width of proximal urethral dilation during coughing and Valsalva maneuver and to report its use in a group of stress-incontinent and continent women. Fifty-eight women were evaluated, 30 with and 28 without stress incontinence proven urodynamically, with a bladder volume of 300 mL and the subjects upright. Urethral pressure profiles at rest were performed with a 10 French microtip pressure catheter. Bladder neck dilation and descent were assessed by perineal ultrasound (5 MHz curved linear array transducer) with the help of ultrasound contrast medium (galactose suspension-Echovist-300), whereas abdominal pressure was assessed with an intrarectal balloon catheter. Statistical analysis used the nonparametric Mann-Whitney test. The depth and diameter of urethral dilation could be measured in all women. During Valsalva, all 30 incontinent women exhibited urethral dilation. One incontinent woman showed dilation only while performing a Valsalva maneuver, not during coughing. In the continent group, 12 women presented dilation during Valsalva and six during coughing. In continent women, dilation was visible only in those who were parous. Nulliparous women did not have dilation during Valsalva or coughing. Bladder neck descent was visible in continent and incontinent women. This method permits quantification of depth and diameter of bladder neck dilation, showing that both incontinent and continent women might have bladder neck dilation and that urinary continence can be established at different locations along the urethra in different women. Parity seems to be a main prerequisite for a proximal urethral defect with bladder neck dilation.

Traumatic tracheobronchial stricture treated with the Eder-Puestow dilator.

PubMed

Erichsen, H G

1980-09-01

A case of tracheobronchial stenosis secondary to trauma is presented. Primary reconstruction resulted in stricture in the distal part of the trachea. Resection and anastomosis was followed by restenosis, which had to be treated endoscopically. Endobronchial resections and forceful dilatations with stiff bronchoscopes were done weekly for about 11 months without lasting benefit. After changing to Eder-Puestow dilators, the dilatations could be done at steadily increasing intervals. This method of dilatation was found to be safe, effective and less traumatic.

Dilatancy Criteria for Salt Cavern Design: A Comparison Between Stress- and Strain-Based Approaches

NASA Astrophysics Data System (ADS)

Labaune, P.; Rouabhi, A.; Tijani, M.; Blanco-Martín, L.; You, T.

2018-02-01

This paper presents a new approach for salt cavern design, based on the use of the onset of dilatancy as a design threshold. In the proposed approach, a rheological model that includes dilatancy at the constitutive level is developed, and a strain-based dilatancy criterion is defined. As compared to classical design methods that consist in simulating cavern behavior through creep laws (fitted on long-term tests) and then using a criterion (derived from short-terms tests or experience) to determine the stability of the excavation, the proposed approach is consistent both with short- and long-term conditions. The new strain-based dilatancy criterion is compared to a stress-based dilatancy criterion through numerical simulations of salt caverns under cyclic loading conditions. The dilatancy zones predicted by the strain-based criterion are larger than the ones predicted by the stress-based criteria, which is conservative yet constructive for design purposes.

Topical Mitomycin C application in the treatment of refractory benign esophageal strictures in adults and comprehensive literature review.

PubMed

Bartel, Michael J; Seeger, Kristina; Jeffers, Kayin; Clayton, Donnesha; Wallace, Michael B; Raimondo, Massimo; Woodward, Timothy A

2016-09-01

Recurrent complex esophageal strictures remain difficult to manage. To determine the efficacy of topical Mitomycin C application for recurrent benign esophageal strictures. All patients who underwent balloon dilation followed by topical Mitomycin C application for recurrent benign esophageal strictures were included. Primary outcome was number of dilations and change of dysphagia score. Nine patients with anastomotic (3), radiation-induced (3), caustic (2), and combined anastomotic and radiation-induced (1) strictures were included. Strictures had a mean length of 13.75mm, diameter of 8.0mm, and were dilated 10.7 times over a median of 8 months (1.5 dilations per month). Following Mitomycin C application, the need for further dilation decreased to 0.39 dilations per month over a median of 10 months; however, dysphagia scores improved not significantly from 3.2 to 2.6 (mean). In this pilot study, topical Mitomycin C in conjunction with dilation decreased the frequency of esophageal dilations for recurrent benign esophageal strictures. Copyright © 2016 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Focal dilation and paradoxical collapse of cortical fissures and sulci in patients with normal-pressure hydrocephalus.

PubMed

Holodny, A I; George, A E; de Leon, M J; Golomb, J; Kalnin, A J; Cooper, P R

1998-11-01

The authors describe a subgroup of patients with shunt-proven normal-pressure hydrocephalus (NPH) who presented with focal fissural and sulcal dilation on imaging studies. The specific radiological features and methods of differentiating this condition from cortical atrophy are delineated. Normal-pressure hydrocephalus has been described as dilation of the ventricles that is out of proportion to the sulci. Sulcal dilation has been taken as evidence of cortical atrophy and has even been used as a criterion to exclude patients from undergoing a shunting procedure. The authors describe five cases of patients with shunt-proven NPH who presented with focal dilation of cortical fissures and sulci. In three of the cases, there was a paradoxical decrease in the size of the dilated fissures and sulci that paralleled the decrease in the size of the lateral ventricles following successful shunting. This study demonstrates that focal fissural and sulcal dilation may represent reservoirs of cerebrospinal fluid analogous to the ventricular system. Patients should not be denied a shunting procedure solely on the basis of focally dilated fissures of sulci.

[Endoscopic contribution in the dilatation of caustic esophagus stenosis].

PubMed

Seydou, Togo; Abdoulaye, Ouattara Moussa; Xing, Li; Zi, Sanogo Zimogo; Sekou, Koumaré; Wen, Yang Shang; Ibrahim, Sankare; Sekou, Toure Cheik Ahmed; Boubacar, Maiga Ibrahim; Saye, Jacque; Jerome, Dakouo Dodino; Dantoumé, Toure Ousmane; Sadio, Yena

2016-01-01

The aim of this work was to present the contribution of the endoscopy in the management of esophageal dilatation for caustic esophageal stenosis (CES). This was a descriptive and prospective study in the thoracic surgery department at the Hospital of Mali. A total of 46 cases of CES is recorded and divided into 4 groups according to the topography of the esophageal lesions. For the different methods of dilatation the number of performed endoscopic support was determined to understand the contribution of endoscopic means in the success of dilatation for CES. The outcome, complications and mortality in the two methods were compared. Fibroscopy was used in 41.30% of patients with Savary Guillard dilators and in 47.82% of patients with Lerut dilators. Video laryngoscopy was used in 58.69% of patients who underwent dilatation with Lerut dilators. The passage of the guide wire was performed in 39.13% under video laryngoscopy and 58.68% under fibroscopy. In comparison of the two methods, there is a significant difference in the occurrence of complications (p=0.04075), general anesthesia (p=0.02287), accessibility (p=0.04805) and mortality (p=0.00402). The CES is a serious disease and under evaluated in Mali. The endoscopies contribute significantly to the success of esophageal dilatation for caustic stenosis in the different methods we used.

A comparison among four tract dilation methods of percutaneous nephrolithotomy: a systematic review and meta-analysis.

PubMed

Dehong, Cao; Liangren, Liu; Huawei, Liu; Qiang, Wei

2013-11-01

The purpose of this study was to evaluate the efficacy and safety of the Amplatz dilation (AD), metal telescopic dilation (MTD), balloon dilation (BD), and one-shot dilation (OSD) methods for tract dilation during percutaneous nephrolithotomy (PCNL). Relevant eligible studies were identified using three electronic databases (Medline, EMBASE, and Cochrane CENTRAL). Database acquisition and quality evaluation were independently performed by two reviewers. Efficacy (stone-free rate, surgical duration, and tract dilatation fluoroscopy time) and safety (transfusion rate and hemoglobin decrease) were evaluated using Review Manager 5.2. Four randomized controlled trials and eight clinical controlled trials involving 6,820 patients met the inclusion criteria. The pooled result from a meta-analysis showed statistically significant differences in tract dilatation fluoroscopy time and hemoglobin decrease between the OSD and MTD groups, which showed comparable stone-free and transfusion rates. Significant differences in transfusion rate were found between the BD and MTD groups. Among patients without previous open renal surgery, those who underwent BD exhibited a lower blood transfusion rate and a shorter surgical duration compared with those who underwent AD. The OSD technique is safer and more efficient than the MTD technique for tract dilation during PCNL, particularly in patients with previous open renal surgery, resulting in a shorter tract dilatation fluoroscopy time and a lesser decrease in hemoglobin. The efficacy and safety of BD are better than AD in patients without previous open renal surgery. The OSD technique should be considered for most patients who undergo PCNL therapy.

Health-Care Utilization and Complications of Endoscopic Esophageal Dilation in a National Population

PubMed Central

Goyal, Abhinav; Chatterjee, Kshitij; Yadlapati, Sujani; Singh, Shailender

2017-01-01

Background/Aims Esophageal stricture is usually managed with outpatient endoscopic dilation. However, patients with food impaction or failure to thrive undergo inpatient dilation. Esophageal perforation is the most feared complication, and its risk in inpatient setting is unknown. Methods We used National Inpatient Sample (NIS) database for 2007–2013. International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) codes were used to identify patients with esophageal strictures. Logistic regression was used to assess association between hospital/patient characteristics and utilization of esophageal dilation. Results There were 591,187 hospitalizations involving esophageal stricture; 4.2% were malignant. Endoscopic dilation was performed in 28.7% cases. Dilation was more frequently utilized (odds ratio [OR], 1.36; p<0.001), had higher in-hospital mortality (3.1% vs. 1.4%, p<0.001), and resulted in longer hospital stays (5 days vs. 4 days, p=0.01), among cases of malignant strictures. Esophageal perforation was more common in the malignant group (0.9% vs. 0.5%, p=0.007). Patients with malignant compared to benign strictures undergoing dilation were more likely to require percutaneous endoscopic gastrostomy or jejunostomy (PEG/J) tube (14.1% vs. 4.5%, p<0.001). Palliative care services were utilized more frequently in malignant stricture cases not treated with dilation compared to those that were dilated. Conclusions Inpatient endoscopic dilation was utilized in 29% cases of esophageal stricture. Esophageal perforation, although infrequent, is more common in malignant strictures. PMID:28301921

Randomized controlled trial comparing esophageal dilation to no dilation among adults with esophageal eosinophilia and dysphagia.

PubMed

Kavitt, R T; Ates, F; Slaughter, J C; Higginbotham, T; Shepherd, B D; Sumner, E L; Vaezi, M F

2016-11-01

The role of esophageal dilation in patients with esophageal eosinophilia with dysphagia remains unknown. The practice of dilation is currently based on center preferences and expert opinion. The aim of this study is to determine if, and to what extent, dysphagia improves in response to initial esophageal dilation followed by standard medical therapies. We conducted a randomized, blinded, controlled trial evaluating adult patients with dysphagia and newly diagnosed esophageal eosinophilia from 2008 to 2013. Patients were randomized to dilation or no dilation at time of endoscopy and blinded to dilation status. Endoscopic features were graded as major and minor. Subsequent to randomization and endoscopy, all patients received fluticasone and dexlansoprazole for 2 months. The primary study outcome was reduction in overall dysphagia score, assessed at 30 and 60 days post-intervention. Patients with severe strictures (less than 7-mm esophageal diameter) were excluded from the study. Thirty-one patients were randomized and completed the protocol: 17 randomized to dilation and 14 to no dilation. Both groups were similar with regard to gender, age, eosinophil density, endoscopic score, and baseline dysphagia score. The population exhibited moderate to severe dysphagia and moderate esophageal stricturing at baseline. Overall, there was a significant (P < 0.001) but similar reduction in mean dysphagia score at 30 and 60 days post-randomization compared with baseline in both groups. No significant difference in dysphagia scores between treatment groups after 30 (P = 0.93) or 60 (P = 0.21) days post-intervention was observed. Esophageal dilation did not result in additional improvement in dysphagia score compared with treatment with proton pump inhibitor and fluticasone alone. In patients with symptomatic esophageal eosinophilia without severe stricture, dilation does not appear to be a necessary initial treatment strategy. © 2015 International Society for Diseases of the Esophagus.

Nitroglycerin mediated dilation evaluated by ultrasound is associated with sTWEAK in hemodialysis patients.

PubMed

Rusu, Crina Claudia; Ghervan, Liviu; Racasan, Simona; Kacsa, Ina; Moldovan, Diana; Potra, Alina; Bondor, Cosmina; Anton, Florin; Patiu, Ioan Mihai; Caprioara, Mirela Gherman

2016-03-01

The main cause of death in hemodialysis (HD) patients is cardiovascular disease. Ultrasound assessment of the brachial artery dysfunction is easily achievable and can non-invasively detect atherosclerosis in various stages. In HD patients the cardiovascular risk profile is different and the determinants of brachial arterial function can be distinct comparing with general population. The aim of the study is to assess the determinants of arterial brachial function (flow-mediated and nitroglycerin-mediated dilation) evaluated by ultrasound in HD patients and their relation with tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) described as atherosclerotic marker in chronic kidney disease patients. We conducted a cross-sectional observational study on 54 hemodialysis patients. We recorded clinical and biological data and we measured sTWEAK serum levels by ELISA. We evaluated the arterial brachial function by measurement of flow-mediated and nitroglycerin-mediated dilation, using B mode ultrasound. The determinants of flow-mediated dilation were: Kt/V (r=0.47, p<0.001), LDL-cholesterol (r=0.29, p=0.04), and total cholesterol (r=0.31, p=0.02). Flow-mediated dilation correlated with nitroglycerin-mediated dilation (r=0.70, p<0.001). In multivariate analysis kt/V was the only significant predictor for flow-mediated dilation (p=0.04). Nitroglycerin-mediated dilation correlates with sTWEAK (r=-0.30, p=0.03), systolic blood pressure (r=-0.28, p=0.04) and pulse pressure (r=-0.31, p=0.02). In multivariate analysis sTWEAK was the only significant predictor for nitroglycerin-mediated dilation (p=0.04). The main determinant of nitroglycerin-mediated dilation was sTWEAK. In addition, decreased nitroglycerin-mediated dilation was associated with higher systolic blood pressure and pulse pressure. The main determinant of FMD was Kt/V. Increased flow-mediated dilation was associated with better dialysis efficiency and high total cholesterol and LDL-cholesterol.

Hygroscopic dilators vs balloon catheter ripening of the cervix for induction of labor in nulliparous women at term: Retrospective study

PubMed Central

Shindo, Ryosuke; Yonemoto, Naohiro; Yamamoto, Yuriko; Kasai, Junko; Kasai, Michi; Miyagi, Etsuko

2017-01-01

Objective To compare the efficacy and safety of hygroscopic dilators and balloon catheters for ripening of the cervix in induction of labor. Study design This retrospective, observational study used data from the Successive Pregnancy Birth Registry System of the Japan Society of Obstetrics and Gynecology from 2012 to 2014. Nulliparous women in whom labor was induced by mechanical methods of cervical ripening at term were enrolled. The eligible women were divided into dilator, balloon <40 mL, balloon ≧40 mL, and overlapping groups. Results The groups included 4645, 4100, 6615, and 1992 women, respectively. In the overlapping group, which included the women in whom delivery was most difficult, the vaginal delivery rate was lower and the intrauterine infection and neonatal mortality rates were higher than those in the dilator group. No difference in the vaginal delivery rate was observed among the dilator, balloon <40 mL, and balloon ≧40 mL groups (74.6%, 72.3%, and 73.8%, respectively; p>0.05). The vaginal instrumental delivery rate was higher in the two-balloon groups than in the dilator group. The volume of intrapartum hemorrhage was lowest in the dilator group. No significant difference in the frequencies of uterine rupture and intrauterine infection were observed among the dilator and two-balloon groups. With regard to neonatal outcomes, the frequency of a low Apgar score was statistically significantly lower in the dilator group than in the two-balloon groups. Moreover, the frequency of neonatal death tended to be lower in the dilator group than in the two-balloon groups. Conclusion With regard to cervical ripening for labor induction in nulliparous women at term, the vaginal delivery rate on using a dilator and on using a balloon seems to be equivalent. Concerning maternal complications and neonatal outcomes, cervical ripening with hygroscopic dilators in labor induction might be safer. PMID:29272277

Impaired activity of adherens junctions contributes to endothelial dilator dysfunction in ageing rat arteries.

PubMed

Chang, Fumin; Flavahan, Sheila; Flavahan, Nicholas A

2017-08-01

Ageing-induced endothelial dysfunction contributes to organ dysfunction and progression of cardiovascular disease. VE-cadherin clustering at adherens junctions promotes protective endothelial functions, including endothelium-dependent dilatation. Ageing increased internalization and degradation of VE-cadherin, resulting in impaired activity of adherens junctions. Inhibition of VE-cadherin clustering at adherens junctions (function-blocking antibody; FBA) reduced endothelial dilatation in young arteries but did not affect the already impaired dilatation in old arteries. After junctional disruption with the FBA, dilatation was similar in young and old arteries. Src tyrosine kinase activity and tyrosine phosphorylation of VE-cadherin were increased in old arteries. Src inhibition increased VE-cadherin at adherens junctions and increased endothelial dilatation in old, but not young, arteries. Src inhibition did not increase dilatation in old arteries treated with the VE-cadherin FBA. Ageing impairs the activity of adherens junctions, which contributes to endothelial dilator dysfunction. Restoring the activity of adherens junctions could be of therapeutic benefit in vascular ageing. Endothelial dilator dysfunction contributes to pathological vascular ageing. Experiments assessed whether altered activity of endothelial adherens junctions (AJs) might contribute to this dysfunction. Aortas and tail arteries were isolated from young (3-4 months) and old (22-24 months) F344 rats. VE-cadherin immunofluorescent staining at endothelial AJs and AJ width were reduced in old compared to young arteries. A 140 kDa VE-cadherin species was present on the cell surface and in TTX-insoluble fractions, consistent with junctional localization. Levels of the 140 kDa VE-cadherin were decreased, whereas levels of a TTX-soluble 115 kDa VE-cadherin species were increased in old compared to young arteries. Acetylcholine caused endothelium-dependent dilatation that was decreased in old compared to young arteries. Disruption of VE-cadherin clustering at AJs (function-blocking antibody, FBA) inhibited dilatation to acetylcholine in young, but not old, arteries. After the FBA, there was no longer any difference in dilatation between old and young arteries. Src activity and tyrosine phosphorylation of VE-cadherin were increased in old compared to young arteries. In old arteries, Src inhibition (saracatinib) increased: (i) 140 kDa VE-cadherin in the TTX-insoluble fraction, (ii) VE-cadherin intensity at AJs, (iii) AJ width, and (iv) acetylcholine dilatation. In old arteries treated with the FBA, saracatinib no longer increased acetylcholine dilatation. Saracatinib did not affect dilatation in young arteries. Therefore, ageing impairs AJ activity, which appears to reflect Src-induced phosphorylation, internalization and degradation of VE-cadherin. Moreover, impaired AJ activity can account for the endothelial dilator dysfunction in old arteries. Restoring endothelial AJ activity may be a novel therapeutic approach to vascular ageing. © 2017 The Authors. The Journal of Physiology © 2017 The Physiological Society.

The impact law of confining pressure and plastic parameter on Dilatancy of rock

NASA Astrophysics Data System (ADS)

Wang, Bin; Zhang, Zhenjie; Zhu, Jiebing

2017-08-01

Based on cyclic loading-unloading triaxle test of marble, the double parameter dilation angle model is established considering confining pressure effect and plastic parameter. Research shows that not only the strength but also the militancy behavior is highly depended on its confining pressure and plastic parameter during process of failure. Dilation angle evolution law shows obvious nonlinear characteristic almost with a rapid increase to the peak and then decrease gradually with plastic increasing, and the peak dilation angle value is inversely proportional with confining pressure. The proposed double parameter nonlinear dilation angle model can be used to well describe the Dilatancy of rock, which helps to understand the failure mechanism of surrounding rock mass and predict the range of plastic zone.

The effect of pneumatic dilation in management of postfundoplication dysphagia.

PubMed

Sunjaya, D; Podboy, A; Blackmon, S H; Katzka, D; Halland, M

2017-06-01

Fundoplication surgery is a commonly performed procedure for gastro-esophageal reflux disease or hiatal hernia repair. Up to 10% of patients develop persistent postoperative dysphagia after surgery. Data on the effectiveness of pneumatic dilation for treatment are limited. The aim of this study was to evaluate clinical outcomes and identify clinical factors associated with successful response to pneumatic dilation among patients with persistent postfundoplication dysphagia (PPFD). We retrospectively evaluated patients who had undergone pneumatic dilation for PPFD between 1999 and 2016. Patients with dysphagia or achalasia prior to fundoplication were excluded. Demographic information, surgical history, severity of dysphagia, and clinical outcomes were collected. Data pertaining to esophagram, manometry, endoscopy, and pneumatic dilation were also collected. We identified 38 patients (82% female, 95% Caucasian, and median age 59 years) with PPFD who completed pneumatic dilation. The median postfundoplication dysphagia score was 2. Eleven patients had abnormal peristalsis on manometry. Seventeen patients reported response (seven complete) with an average decrease of 1 in their dysphagia score. Fifteen patients underwent reoperation due to PPFD. Hiatal hernia repair was the only factor that predicts a higher response rate to pneumatic dilation. Only one patient in our study developed complication (pneumoperitoneum) from pneumatic dilation. We found that pneumatic dilation to be a safe treatment option for PPFD with moderate efficacy. Patients who developed PPFD after a hiatal hernia repair may gain the greatest benefit after pneumatic dilation. We were not able to identify additional clinical, radiological, endoscopic, or manometric parameters that were predictive of response. © 2017 John Wiley & Sons Ltd.

A comparison of two methods of endoscopic dilation of acute subglottic stenosis using a ferret model.

PubMed

Tubbs, Kyle J; Silva, Rodrigo C; Ramirez, Harvey E; Castleman, William L; Collins, William O

2013-01-01

Balloon dilation is accepted as a first line treatment of acute subglottic stenosis, but its effects on the subglottic tissue remain largely unknown. We aimed to develop an animal model of acute subglottic stenosis using endoscopic techniques. Once developed, this model was used to compare the immediate effects of balloon dilation and endotracheal tube dilation on subglottic tissue. Prospective randomized animal study. Acute subglottic injury was induced in 10 ferrets by endoscopic cauterization with silver nitrate. After 48-72 hours of observation, eight animals were randomized to undergo subglottic dilation with either a 5-mm balloon or endotracheal tubes of increasing diameter. These eight ferrets were euthanized within 10 minutes after dilation. The other two ferrets served as controls and were euthanized following observation only. The larynx from each ferret was harvested, and the subglottis was examined histologically by a pathologist blinded to the treatment arms. Acute subglottic stenosis was induced in all 10 ferrets using the endoscopic technique. Both balloon and endotracheal tube dilation resulted in comparable improvement in the subglottic airway diameter. A decreased thickness of submucosa/lamina propria was seen in the balloon dilation group. Acute subglottic stenosis can be reliably induced in ferrets using endoscopic techniques. Multiple dilation methods can be used to relieve acute obstruction. Balloon dilators seem to improve airway patency, in part, by decreasing the thickness of the submucosa and lamina propria. Further research is needed to determine how this impacts later stages of wound healing and final outcomes. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

Endoscopic dilation for treatment of anastomotic leaks following transhiatal esophagectomy.

PubMed

Bhasin, D K; Sharma, B C; Gupta, N M; Sinha, S K; Singh, K

2000-06-01

Anastomotic leak is a known complication after transhiatal esophagectomy (THE) and cervical esophagogastric anastomosis. Conservative management takes a long time to heal such leaks. We assessed the role of endoscopic dilation in patients with anastomotic leak following THE. Eight consecutive patients (seven men, one woman; mean age 51) with anastomotic leak following THE were subjected to endoscopic dilation using Savary Gilliard dilators of 7-15 mm diameter. The mean interval between surgery and detection of leak was 9 days (range 5-22 days) and dilation was performed at a mean interval of 11.4 days (range 1-20 days) after detection of the leak. Drainage from fistulas stopped completely after 1-8 days (mean 3 days). X-ray with water soluble contrast showed closure of the fistula in all cases. Duration of follow-up ranged from 2 to 12 months. Anastomotic strictures developed in three patients. These patients required three sessions each of repeat dilation, and were alive at follow-up periods of 2, 4, and 12 months, respectively. One patient developed recurrence of growth at an anastomotic site. Four patients died because of distant metastasis. Bougie dilation of anastomotic sites is a safe and effective technique for the healing of anastomotic leaks following THE. However there is a need for a prospective randomized trial comparing endoscopic dilation with no dilation in patients with anastomotic leaks following THE.

Pupil dilation signals uncertainty and surprise in a learning gambling task.

PubMed

Lavín, Claudio; San Martín, René; Rosales Jubal, Eduardo

2013-01-01

Pupil dilation under constant illumination is a physiological marker where modulation is related to several cognitive functions involved in daily decision making. There is evidence for a role of pupil dilation change during decision-making tasks associated with uncertainty, reward-prediction errors and surprise. However, while some work suggests that pupil dilation is mainly modulated by reward predictions, others point out that this marker is related to uncertainty signaling and surprise. Supporting the latter hypothesis, the neural substrate of this marker is related to noradrenaline (NA) activity which has been also related to uncertainty signaling. In this work we aimed to test whether pupil dilation is a marker for uncertainty and surprise in a learning task. We recorded pupil dilation responses in 10 participants performing the Iowa Gambling Task (IGT), a decision-making task that requires learning and constant monitoring of outcomes' feedback, which are important variables within the traditional study of human decision making. Results showed that pupil dilation changes were modulated by learned uncertainty and surprise regardless of feedback magnitudes. Interestingly, greater pupil dilation changes were found during positive feedback (PF) presentation when there was lower uncertainty about a future negative feedback (NF); and by surprise during NF presentation. These results support the hypothesis that pupil dilation is a marker of learned uncertainty, and may be used as a marker of NA activity facing unfamiliar situations in humans.

Pupil dilation signals uncertainty and surprise in a learning gambling task

PubMed Central

Lavín, Claudio; San Martín, René; Rosales Jubal, Eduardo

2014-01-01

Pupil dilation under constant illumination is a physiological marker where modulation is related to several cognitive functions involved in daily decision making. There is evidence for a role of pupil dilation change during decision-making tasks associated with uncertainty, reward-prediction errors and surprise. However, while some work suggests that pupil dilation is mainly modulated by reward predictions, others point out that this marker is related to uncertainty signaling and surprise. Supporting the latter hypothesis, the neural substrate of this marker is related to noradrenaline (NA) activity which has been also related to uncertainty signaling. In this work we aimed to test whether pupil dilation is a marker for uncertainty and surprise in a learning task. We recorded pupil dilation responses in 10 participants performing the Iowa Gambling Task (IGT), a decision-making task that requires learning and constant monitoring of outcomes’ feedback, which are important variables within the traditional study of human decision making. Results showed that pupil dilation changes were modulated by learned uncertainty and surprise regardless of feedback magnitudes. Interestingly, greater pupil dilation changes were found during positive feedback (PF) presentation when there was lower uncertainty about a future negative feedback (NF); and by surprise during NF presentation. These results support the hypothesis that pupil dilation is a marker of learned uncertainty, and may be used as a marker of NA activity facing unfamiliar situations in humans. PMID:24427126

Cervical dilation before first-trimester surgical abortion (<14 weeks' gestation).

PubMed

Allen, Rebecca H; Goldberg, Alisa B

2016-04-01

First-trimester surgical abortion is a common, safe procedure with a major complication rate of less than 1%. Cervical dilation before suction abortion is usually accomplished using tapered mechanical dilators. Risk factors for major complications in the first trimester include increasing gestational age and provider inexperience. Cervical priming before first-trimester surgical abortion has been studied using osmotic dilators and pharmacologic agents, most commonly misoprostol. Extensive data demonstrate that a variety of agents are safe and effective at causing preoperative cervical softening and dilation; however, given the small absolute risk of complications, the benefit of routine use of misoprostol or osmotic dilators in first-trimester surgical abortion is unclear. Although cervical priming results in reduced abortion time and improved provider ease, it requires a delay of at least 1 to 3 h and may confer side effects. The Society of Family Planning does not recommend routine cervical priming for first-trimester suction abortion but recommends limiting consideration of cervical priming for women at increased risk of complications from cervical dilation, including those late in the first trimester, adolescents and women in whom cervical dilation is expected to be challenging. Copyright © 2016 Elsevier Inc. All rights reserved.

Balloon dilatation of nasopharyngeal stenosis in a dog.

PubMed

Berent, Allyson C; Kinns, Jennifer; Weisse, Chick

2006-08-01

A dog was examined because of a 6-month history of upper airway stridor that began after postoperative regurgitation of gastric contents. Constant stridor was evident during inspiration and expiration, although it was worse during inspiration. The stridor was no longer evident when the dog's mouth was manually held open. Computed tomography, rhinoscopy, and fluoroscopy were used to confirm a diagnosis of nasopharyngeal stenosis. The dog was anesthetized, and balloon dilatation of the stenosis was performed. Prednisone was prescribed for 4 weeks after the procedure to decrease fibrous tissue formation. Although the dog was initially improved, signs recurred 3.5 weeks later, and balloon dilatation was repeated. This time, however, triamcinolone was injected into the area of stenosis at the end of the dilatation procedure. Two months later, although the dog did not have clinical signs of stridor, a third dilatation procedure was performed because mild stenosis was seen on follow-up computed tomographic images; again, triamcinolone was injected into the area of stenosis at the end of the dilatation procedure. Three and 6 months after the third dilatation procedure, the dog reportedly was clinically normal. Findings suggest that balloon dilatation may be an effective treatment for nasopharyngeal stenosis in dogs.

Treatments for pediatric achalasia: Heller myotomy or pneumatic dilatation?

PubMed

Jung, C; Michaud, L; Mougenot, J-F; Lamblin, M-D; Philippe-Chomette, P; Cargill, G; Bonnevalle, M; Boige, N; Bellaïche, M; Viala, J; Hugot, J-P; Gottrand, F; Cezard, J-P

2010-03-01

The treatment of achalasia consists of reducing distal esophageal obstruction by either Heller myotomy surgery or endoscopic pneumatic dilatation. The aim of the present study was to evaluate the short- and middle-term results of these procedures in children. For technical reasons, children under six years old (n=8) were treated by surgery only, whereas patients over six years old (n=14) were treated by either Heller myotomy or pneumatic dilatation. Of the children aged under six years, 75% were symptom-free at six months and 83% at 24 months of follow-up. Of the patients aged over six years, complete remission was achieved by Heller myotomy in 44.5% vs. 55.5% by pneumatic dilatation after six months, and in 40% vs. 65%, respectively, after 24 months. Both pneumatic dilatation and Heller myotomy showed significant rates of failure. These results suggest that pneumatic dilatation may be considered a primary treatment in children over six years old. Also, where necessary, Heller myotomy and pneumatic dilatation may be used as complementary treatments.

Crack Damage Parameters and Dilatancy of Artificially Jointed Granite Samples Under Triaxial Compression

NASA Astrophysics Data System (ADS)

Walton, G.; Alejano, L. R.; Arzua, J.; Markley, T.

2018-06-01

A database of post-peak triaxial test results was created for artificially jointed planes introduced in cylindrical compression samples of a Blanco Mera granite. Aside from examining the artificial jointing effect on major rock and rock mass parameters such as stiffness, peak strength and residual strength, other strength parameters related to brittle cracking and post-yield dilatancy were analyzed. Crack initiation and crack damage values for both the intact and artificially jointed samples were determined, and these damage envelopes were found to be notably impacted by the presence of jointing. The data suggest that with increased density of jointing, the samples transition from a combined matrix damage and joint slip yielding mechanism to yield dominated by joint slip. Additionally, post-yield dilation data were analyzed in the context of a mobilized dilation angle model, and the peak dilation angle was found to decrease significantly when there were joints in the samples. These dilatancy results are consistent with hypotheses in the literature on rock mass dilatancy.

Pupil dilation during recognition memory: Isolating unexpected recognition from judgment uncertainty.

PubMed

Mill, Ravi D; O'Connor, Akira R; Dobbins, Ian G

2016-09-01

Optimally discriminating familiar from novel stimuli demands a decision-making process informed by prior expectations. Here we demonstrate that pupillary dilation (PD) responses during recognition memory decisions are modulated by expectations, and more specifically, that pupil dilation increases for unexpected compared to expected recognition. Furthermore, multi-level modeling demonstrated that the time course of the dilation during each individual trial contains separable early and late dilation components, with the early amplitude capturing unexpected recognition, and the later trailing slope reflecting general judgment uncertainty or effort. This is the first demonstration that the early dilation response during recognition is dependent upon observer expectations and that separate recognition expectation and judgment uncertainty components are present in the dilation time course of every trial. The findings provide novel insights into adaptive memory-linked orienting mechanisms as well as the general cognitive underpinnings of the pupillary index of autonomic nervous system activity. Copyright © 2016 Elsevier B.V. All rights reserved.

Spectral dilation of L(B,H)-valued measures and its application to stationary dilation for Banach space valued processes

NASA Technical Reports Server (NTRS)

Miamee, A. G.

1988-01-01

Let B be a Banach space and H and K two Hilbert spaces. The spectral dilation of L(B,H)-valued measures is studied and it is shown that the recent results of Makagon and Salehi (1986) and Rosenberg (1982) on the dilation of L(K,H)-valued measures can be extended to hold for the general Banach space setting of L(B,H)-valued measures. These L(B,H)-valued measures are closely connected to the Banach space valued processes. This connection is recalled and as application of spectral dilation of L(B,H)-valued measures the well known stationary dilation results for scalar valued processes is extended to the case of Banach space valued processes.

Increased plasma asymmetric dimethylarginine level is associated with ascending aorta dilatation: a case-control study.

PubMed

Satılmışoğlu, Muhammet Hulusi; Örnek Diker, Vesile; Taşbulak, Ömer; Diker, Mustafa; Birand, Ali; Kaya, Mehmet; İyigün, Taner; Eksik, Abdurrahman

2017-01-01

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase. We aimed to determine plasma ADMA levels in patients with ascending aorta dilatation in comparison to those without aorta dilatation, and to evaluate the diagnostic, predictive, and prognostic value of serum ADMA level for aorta dilatation. This was a cross-sectional case-control study. A total of 104 consecutive patients (female/male, 35/69; mean age, 62.75 ± 13.11 years) diagnosed with ascending aorta dilatation (≥ 4.5 cm) on echocardiography (case group), and 52 age-and gender-matched patients (female/male, 17/35; mean age, 63.44 ± 7.56 years) with normal aorta dimensions (≤ 3.8 cm) (control group) were included. Routine biochemical and haematological analysis in addition to measurement of serum ADMA level were performed. The mean diameter of ascending aorta measured on echocardiography was 4.95 ± 0.57 cm and 3.34 ± 0.36 cm in patients with aorta dilatation and those without aorta dilatation, respectively (p < 0.001). Serum ADMA level was significantly higher in patients with aorta dilatation than in the control group (1.70 ± 1.12 μmol/L vs. 0.79 ± 0.76 μmol/L, respectively, p < 0.001). There was significant positive correlation between ADMA level and aortic diameter in Spearman correlation analysis (r = 0.317, p < 0.001). In linear regression analysis, ADMA was found to be a significant independent predictor of aorta diameter (Beta = 0.26, p < 0.001). Receiver-operator characteristic curve analysis also revealed that serum ADMA cut-off level over 0.29 μmol/L predicts aorta dilatation (≥ 4.5 cm) with 94% sensitivity and 92% specificity and with high ac-curacy (area under curve: 0.786; 95% confidence interval: 0.709-0.863, p < 0.001). Serum ADMA level is diagnostic for ascending aorta dilatation with high sensitivity and specificity, and should be considered for use in clinical diagnosis of aorta dilatation.

Risk of recurrent or refractory strictures and outcome of endoscopic dilation for radiation-induced esophageal strictures.

PubMed

Agarwalla, Anant; Small, Aaron J; Mendelson, Aaron H; Scott, Frank I; Kochman, Michael L

2015-07-01

Radiation therapy for head, neck, and esophageal cancer can result in esophageal strictures that may be difficult to manage. Radiation-induced esophageal strictures often require repeat dilation to obtain relief of dysphagia. This study aimed to determine the long-term clinical success and rates of recurrent and refractory stenosis in patients with radiation-induced strictures undergoing dilation. Retrospective cohort study of patients with radiation-induced strictures who underwent endoscopic dilation by a single provider from October 2007-October 2012. Outcomes measured included long-term clinical efficacy, interval between sessions, number of dilations, and proportion of radiation strictures that were recurrent or refractory. Risk factors for refractory strictures were assessed. 63 patients underwent 303 dilations. All presented with a stricture >30 days after last radiation session. Clinical success to target diameter was achieved in 52 patients (83%). A mean of 3.3 (±2.6) dilations over a median period of 4 weeks was needed to achieve initial patency. Recurrence occurred in 17 (33%) at a median of 22 weeks. Twenty-seven strictures (43%) were refractory to dilation therapy. Fluoroscopy during dilation (OR 22.88; 95% CI 3.19-164.07), severe esophageal stenosis (lumen <9 mm) (OR 10.51; 95% CI 1.94-56.88), and proximal location with prior malignancy extrinsic to the lumen (OR 6.96; 95% CI 1.33-36.29) were independent predictors of refractory strictures in multivariate analysis. (1) Radiation-induced strictures have a delayed onset (>30 days) from time of radiation injury. (2) Endoscopic dilation can achieve medium-term luminal remediation but the strictures have a high long-term recurrence rate of up to 33%. (3) Remediation of radiation strictures following laryngectomy can be achieved but require frequent dilations. (4) Clinical and procedural predictors may identify patients at high risk of refractory strictures. (5) The optimal strategy in highly selected refractory patients is not clear.

Risk of Recurrent or Refractory Strictures and Outcome of Endoscopic Dilation for Radiation-Induced Esophageal Strictures

PubMed Central

Agarwalla, Anant; Small, Aaron J.; Mendelson, Aaron H.; Scott, Frank I.; Kochman, Michael L.

2014-01-01

Background Radiation therapy for head, neck, and esophageal cancer can result in esophageal strictures that may be difficult to manage. Radiation-induced esophageal strictures often require repeat dilation to obtain relief of dysphagia. This study aimed to determine the long-term clinical success and rates of recurrent and refractory stenosis in patients with radiation-induced strictures undergoing dilation. Methods Retrospective cohort study of patients with radiation-induced strictures who underwent endoscopic dilation by a single provider from October 2007– October 2012. Outcomes measured included long-term clinical efficacy, interval between sessions, number of dilations, and proportion of radiation strictures that were recurrent or refractory. Risk factors for refractory strictures were assessed. Results 63 patients underwent 303 dilations. All presented with a stricture > 30 days after last radiation session. Clinical success to target diameter was achieved in 52 patients (83%). A mean of 3.3 (+/− 2.6) dilations over a median period of 4 weeks was needed to achieve initial patency. Recurrence occurred in 17 (33%) at a median of 22 weeks. Twenty-seven strictures (43%) were refractory to dilation therapy. Fluoroscopy during dilation (OR, 22.88; 95% CI, 3.19 – 164.07), severe esophageal stenosis (lumen <9 mm) (OR, 10.51; 95% CI, 1.94 – 56.88), and proximal location with prior malignancy extrinsic to the lumen (OR, 6.96; 95% CI, 1.33 – 36.29) were independent predictors of refractory strictures in multivariate analysis. Conclusions 1. Radiation-induced strictures have a delayed onset (>30 days) from time of radiation injury. 2. Endoscopic dilation can achieve medium-term luminal remediation but the strictures have a high long-term recurrence rate of up to 33%. 3. Remediation of radiation strictures following laryngectomy can be achieved but require frequent dilations. 4. Clinical and procedural predictors may identify patients at high risk of refractory strictures. 5. The optimal strategy in highly selected refractory patients is not clear. PMID:25277484

Balloon dilatation in esophageal strictures in epidermolysis bullosa and the role of anesthesia.

PubMed

Gollu, Gulnur; Ergun, Ergun; Ates, Ufuk; Can, Ozlem S; Dindar, Huseyin

2017-02-01

Esophageal involvement, which causes stricture, is a complication in epidermolysis bullosa. This causes dysphagia and malnutrition and leads to deterioration of skin lesions in these patients. The charts of 11 patients with epidermolysis bullosa and esophageal stricture who were included into dilatation program between 2003 and 2015 were retrospectively reviewed. Seven of the patients were female and four were male. The median age was 14 (2-32) years. The mean body weight of patients was 27.8 (9-51) kg. The location and number of strictured parts of the esophagus were previously evaluated with upper gastrointestinal contrast study and after that flexible endoscopy was used for dilatation. Eight patients had middle esophageal, three patients had proximal esophageal and one of them had both proximal and middle esophageal strictures. The strictures were dilated 56 times in total (mean 5 times). One patient underwent gastrostomy and was medically followed-up after a perforation occurrence during the dilatation procedure. In a 32-year-old female patient, colon interposition was performed after four dilatations since optimal nutritional and developmental status could not be achieved. The dilatation program of nine patients is still in progress. Seven of them can easily swallow solid food but two of them have some difficulties in swallowing between dilatations. One patient rejected the program and quitted, while one patient refused colon interposition and died because of complications related to amyloidosis during the dilatation program. After resolution of the swallowing problem, skin lesions were observed to heal quickly. Epidermolysis bullosa is a rare cause of dysphagia. Esophageal balloon dilatation with flexible endoscopy is a safe and efficient method in patients with this condition. © 2016 International Society for Diseases of the Esophagus.

Evaluation of the Distribution of Paclitaxel After Application of a Paclitaxel-Coated Balloon in the Rabbit Urethra.

PubMed

Barbalias, Dimitrios; Lappas, Georgios; Ravazoula, Panagiotia; Liourdi, Despoina; Kyriazis, Iason; Liatsikos, Evangelos; Kallidonis, Panagiotis

2018-05-01

Urethral strictures are a common urologic problem that could require complex reconstructive procedures. Urethral dilatation represents a frequent practiced intervention associated with high recurrence rates. Drug-coated percutaneous angioplasty balloons (DCBs) with cytostatic drugs have been effectively used for the prevention of vascular restenosis after balloon dilatation. To reduce restenosis rates of urethral dilatation, these balloons could be used in the urethra. Nevertheless, the urothelium is different than the endothelium and these drugs may not be distributed to the outer layers of the urethra. Thus, an experiment was performed to evaluate the distribution of paclitaxel (PTX) in the rabbit urethra after the inflation of a PTX-coated balloon (PCB). Eleven rabbits underwent dilatation of the posterior urethra with common endoscopic balloons after urethrography. Nine of these rabbits were additionally treated with PCB. The urethras of the two control animals were removed along with three more dilated with PCB urethras immediately after the dilatation. The remaining of the urethras were removed after 24 (n = 3) and 48 hours (n = 3). The posterior segments of the urethras were evaluated with hematoxylin and eosin staining as well as with immunohistochemistry with polyclonal anti-PTX antibody. The two control specimens showed denudation of the urothelium after balloon dilatations and no PTX was observed. All specimens from dilated PCB urethras showed distribution of PTX to all layers of the urethra. The specimens that were immediately removed exhibited denudation of the urothelium without any inflammation. The specimens removed at 24 and 48 hours showed mild acute inflammation. PTX was distributed to the urothelial, submucosal, and smooth muscle layers of the normal rabbit urethra immediately after dilatation with a DCB. PTX and mild inflammation were present at the site 24 and 48 hours after the dilatation.

Acute limb heating improves macro- and microvascular dilator function in the leg of aged humans.

PubMed

Romero, Steven A; Gagnon, Daniel; Adams, Amy N; Cramer, Matthew N; Kouda, Ken; Crandall, Craig G

2017-01-01

Local heating of an extremity increases blood flow and vascular shear stress throughout the arterial tree. Local heating acutely improves macrovascular dilator function in the upper limbs of young healthy adults through a shear stress-dependent mechanism but has no such effect in the lower limbs of this age group. The effect of acute limb heating on dilator function within the atherosclerotic prone vasculature of the lower limbs of aged adults is unknown. Therefore, the purpose of this study was to test the hypothesis that acute lower limb heating improves macro- and microvascular dilator function within the leg vasculature of aged adults. Nine young and nine aged adults immersed their lower limbs at a depth of ~33 cm into a heated (~42°C) circulated water bath for 45 min. Before and 30 min after heating, macro (flow-mediated dilation)- and microvascular (reactive hyperemia) dilator functions were assessed in the lower limb, following 5 min of arterial occlusion, via Doppler ultrasound. Compared with preheat, macrovascular dilator function was unchanged following heating in young adults (P = 0.6) but was improved in aged adults (P = 0.04). Similarly, microvascular dilator function, as assessed by peak reactive hyperemia, was unchanged following heating in young adults (P = 0.1) but was improved in aged adults (P < 0.01). Taken together, these data suggest that acute lower limb heating improves both macro- and microvascular dilator function in an age dependent manner. We demonstrate that lower limb heating acutely improves macro- and microvascular dilator function within the atherosclerotic prone vasculature of the leg in aged adults. These findings provide evidence for a potential therapeutic use of chronic lower limb heating to improve vascular health in primary aging and various disease conditions. Copyright © 2017 the American Physiological Society.

Annular dilatation and loss of sino-tubular junction in aneurysmatic aorta: implications on leaflet quality at the time of surgery. A finite element study†

PubMed Central

Weltert, Luca; de Tullio, Marco D.; Afferrante, Luciano; Salica, Andrea; Scaffa, Raffaele; Maselli, Daniele; Verzicco, Roberto; De Paulis, Ruggero

2013-01-01

OBJECTIVES In the belief that stress is the main determinant of leaflet quality deterioration, we sought to evaluate the effect of annular and/or sino-tubular junction dilatation on leaflet stress. A finite element computer-assisted stress analysis was used to model four different anatomic conditions and analyse the consequent stress pattern on the aortic valve. METHODS Theoretical models of four aortic root configurations (normal, with dilated annulus, with loss of sino-tubular junction and with both dilatation simultaneously) were created with computer-aided design technique. The pattern of stress and strain was then analysed by means of finite elements analysis, when a uniform pressure of 100 mmHg was applied to the model. Analysis produced von Mises charts (colour-coded, computational, three-dimensional stress-pattern graphics) and bidimensional plots of compared stress on arc-linear line, which allowed direct comparison of stress in the four different conditions. RESULTS Stresses both on the free margin and on the ‘belly’ of the leaflet rose from 0.28 MPa (normal conditions) to 0.32 MPa (+14%) in case of isolated dilatation of the sino-tubular junction, while increased to 0.42 MPa (+67%) in case of isolated annular dilatation, with no substantial difference whether sino-tubular junction dilatation was present or not. CONCLUSIONS Annular dilatation is the key element determining an increased stress on aortic leaflets independently from an associated sino-tubular junction dilatation. The presence of annular dilatation associated with root aneurysm greatly decreases the chance of performing a valve sparing procedure without the need for additional manoeuvres on leaflet tissue. This information may lead to a refinement in the optimal surgical strategy. PMID:23536020

Impairment of left ventricular function during coronary angioplastic occlusion evaluated with a nonimaging scintillation probe.

PubMed

Hartmann, A; Maul, F D; Zimny, M; Klepzig, H; Vallbracht, C; Kneissl, H G; Schräder, R; Hör, G; Kaltenbach, M

1991-09-01

Impairment of left ventricular function during controlled myocardial ischemia induced by coronary angioplasty has been reported from angiographic and echocardiographic studies. Ejection fraction, peak ejection, peak filling rates, and end-systolic and end-diastolic volumes were investigated before, during and after coronary occlusion on-line with a nonimaging scintillation probe. The study consisted of 18 patients (mean age 59 +/- 10 years) with coronary artery stenosis of greater than 70%. During balloon inflation of 60 seconds' duration, coronary occlusion pressure was 31.6 +/- 12 mm Hg. There was no significant change in heart rate. Delay between first and second dilatation was 109 +/- 63 seconds. Ejection fraction decreased from 53 +/- 16 to 40 +/- 12% (first dilatation, p less than 0.01) and to 39 +/- 14% (second dilatation, p less than 0.01) and recovered to 51 +/- 16% 5 minutes after the second dilatation. Peak ejection rate was significantly reduced during the first and second balloon inflations. Peak filling rate decreased from 2.5 +/- 0.8 to 2.0 +/- 0.7 end-diastolic volume.s-1 (first dilatation, p less than 0.01) and to 1.8 +/- 0.7 end-diastolic volume.s-1 (second dilatation, p less than 0.01) and remained reduced at 2.2 +/- 0.7 end-diastolic volume.s-1 (p = not significant) at 5 minutes after the second dilatation. End-systolic and end-diastolic volumes increased significantly during the first and second dilatations and returned to normal after dilatation. It is concluded that short, controlled myocardial ischemia during coronary angioplasty leads to a decrease in systolic and diastolic left ventricular function. Sequential dilatations do not further decrease function if a sufficient interval is kept.

Mechanics of dual-mode dilative failure in subaqueous sediment deposits

NASA Astrophysics Data System (ADS)

You, Yao; Flemings, Peter; Mohrig, David

2014-07-01

We introduce dual-mode dilative failure with flume experiments. Dual-mode dilative failure combines slow and steady release of sediments by breaching with periodic sliding, which rapidly releases an internally coherent wedge of sediments. It occurs in dilative sandy deposits. This periodic slope failure results from cyclic evolution of the excess pore pressure in the deposit. Sliding generates large, transient, negative excess pore pressure that strengthens the deposit and allows breaching to occur. During breaching, negative excess pore pressure dissipates, the deposit weakens, and ultimately sliding occurs once again. We show that the sliding frequency is proportional to the coefficient of consolidation. We find that thicker deposits are more susceptible to dual-mode dilative failure. Discovery of dual-mode dilative failure provides a new mechanism to consider when interpreting the sedimentary deposits linked to submarine slope failures.

Office dilation of the female urethra: a quality of care problem in the field of urology.

PubMed

Santucci, Richard A; Payne, Christopher K; Anger, Jennifer T; Saigal, Christopher S

2008-11-01

Historically dilation of the female urethra was thought to be of value in the treatment of a variety of lower urinary tract symptoms. Subsequent work has more accurately classified these complaints as parts of various diseases or syndromes in which scant data exist to support the use of dilation. Yet Medicare reimbursement for urethral dilation remains generous and we describe practice patterns regarding female urethral dilation to characterize a potential quality of care issue. Health care use by females treated with urethral dilation was compiled using a complementary set of databases. Data sets were examined for relevant inpatient, outpatient and emergency room services for women of all ages. Female urethral dilation is common (929 per 100,000 patients) and is performed almost as much as treatment for male urethral stricture disease. Approximately 12% of these patients are subjected to costly studies such as retrograde urethrography. The overall national costs for treatment exceed $61 million per year and have increased 10% to 17% a year since 1994. A diagnosis of female urethral stricture increases health care expenditures by more than $1,800 per individual per year in insured populations. Urethral dilation is still common despite the fact that true female urethral stricture is an uncommon entity. This scenario is likely secondary to the persistence of the mostly discarded practice of dilating the unstrictured female urethra for a wide variety of complaints despite the lack of data suggesting that it improves lower urinary tract symptoms.

Effects of supramaximal balloon dilatation pressures on adult cricoid and tracheal cartilage: A cadaveric study.

PubMed

Durvasula, Venkata S P B; Shalin, Sara C; Tulunay-Ugur, Ozlem E; Suen, James Y; Richter, Gresham T

2018-06-01

Cricoid fracture is a serious concern for balloon dilatation in airway stenosis. Furthermore, there are no studies examining tracheal rupture in balloon dilatation of stenotic segments. The aim of this study was to evaluate the effect of supramaximal pressures of balloons on the cricoid and tracheal rings. Prospective cadaveric study. Seven cadaveric laryngotracheal complexes of normal adults with intact cricothyroid membranes were acquired. Noncompliant vascular angioplasty balloons (BARD-VIDA) were used for dilatation. The subglottis and trachea were subjected to supramaximal dilatation pressures graduated to nominal burst pressure (NBP) and, if necessary, rated burst pressure (RBP). Larger-diameter balloons, starting from 18 mm size to 24 mm, were used. Dilatations were maintained for 3 minutes. The cricoid ring was disrupted by larger-diameter balloons (22 mm and 24 mm) even at lower pressures (less than NBP) in six cases. Tracheal cartilages were very distensible, and external examination after supramaximal dilatation (24 mm close to RBP) revealed no obvious cartilage fractures or trachealis tears. Histopathological examination revealed sloughing of mucosa in the areas corresponding to balloon placement, but no microfractures or disruption of the perichondrium of tracheal ring cartilages. These results indicate that the cricoid is vulnerable to injury from larger balloons even at lower dilatation pressures. The tracheal cartilages and the membranous wall of the trachea remained resilient to supramaximal dilatation and larger balloons. NA. Laryngoscope, 128:1304-1309, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Emergency Physicians Are Able to Detect Right Ventricular Dilation With Good Agreement Compared to Cardiology.

PubMed

Rutz, Matt A; Clary, Julie M; Kline, Jeffrey A; Russell, Frances M

2017-07-01

Focused cardiac ultrasound (FOCUS) is a useful tool in evaluating patients presenting to the emergency department (ED) with acute dyspnea. Prior work has shown that right ventricular (RV) dilation is associated with repeat hospitalizations and shorter life expectancy. Traditionally, RV assessment has been evaluated by cardiologist-interpreted comprehensive echocardiography. The primary goal of this study was to determine the inter-rater reliability between emergency physicians (EPs) and a cardiologist for determining RV dilation on FOCUS performed on ED patients with acute dyspnea. This was a prospective, observational study at two urban academic EDs; patients were enrolled if they had acute dyspnea and a computed tomographic pulmonary angiogram without acute disease. All patients had an EP-performed FOCUS to assess for RV dilation. RV dilation was defined as an RV to left ventricular ratio greater than 1. FOCUS interpretations were compared to a blinded cardiologist FOCUS interpretation using agreement and kappa statistics. Of 84 FOCUS examinations performed on 83 patients, 17% had RV dilation. Agreement and kappa, for EP-performed FOCUS for RV dilation were 89% (95% confidence interval [CI] 80-95%) and 0.68 (95% CI 0.48-0.88), respectively. Emergency physician sonographers are able to detect RV dilation with good agreement when compared to cardiology. These results support the wider use of EP-performed FOCUS to evaluate for RV dilation in ED patients with dyspnea. © 2017 by the Society for Academic Emergency Medicine.

Histopathology of balloon-dilation Eustachian tuboplasty.

PubMed

Kivekäs, Ilkka; Chao, Wei-Chieh; Faquin, William; Hollowell, Monica; Silvola, Juha; Rasooly, Tali; Poe, Dennis

2015-02-01

Surgical intervention of the Eustachian tube (ET) has become increasingly common in the past decade, and balloon dilation has shown promising results in recent studies. It is unclear how balloon dilation enhances ET function. Our aim was to evaluate histological changes in the ET's mucosal lumen comparing before balloon dilation, immediately after, and postoperatively. Case series. Thirteen patients with bilateral ET dysfunction were enrolled. Biopsies of the ET mucosa were obtained just before balloon dilation; immediately after; and in three cases, 5 to 12 weeks postoperatively. Specimens were retrospectively examined under light microscopy by two pathologists blinded to the clinical information and whether specimens were pre- or postballoon dilation. Preoperative biopsies were characterized by inflammatory changes within the epithelium and submucosal layer. Immediate response to balloon dilation was thinning of the mucosa, shearing of epithelium and crush injury to the submucosa, especially to lymphocytic infiltrates. Postoperative biopsies demonstrated healthy pseudocolumnar epithelium and replacement of lymphocytic infiltrate with a thinner layer of fibrous tissue. Reduction of inflammatory epithelial changes and submucosal inflammatory infiltrate appeared to be the principal result of balloon dilation. The balloon may shear or crush portions of inflamed epithelium but usually spared the basal layer, allowing for rapid healing. Additionally, it appeared to effectively crush lymphocytes and lymphocytic follicles that may become replaced with thinner fibrous scar. Histopathology of the ET undergoing balloon dilation demonstrated effects that could reduce the overall inflammatory burden and may contribute to clinical improvement in ET function. 4. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

Crucial importance of the endothelial K+ channel SK3 and connexin40 in arteriolar dilations during skeletal muscle contraction.

PubMed

Milkau, Malte; Köhler, Ralf; de Wit, Cor

2010-09-01

Skeletal muscle activity requires substantial increases in blood flow, and the underlying vasodilation involves endothelial activity, but the contribution of the endothelium-dependent hyperpolarizing factor (EDHF) is only poorly defined. In EDHF signaling, endothelial hyperpolarization mediated by the Ca(2+)-activated K(+) channels SK3 and IK1 is a key step and also initiates gap junction-dependent conducted dilations. We assessed the role of SK3, IK1, and connexin40 (Cx40) in muscular contraction-induced dilations in the microcirculation in vivo. Hitherto, arterioles were observed in the electrically stimulated cremaster skeletal muscle of anesthetized mice lacking SK3, IK1, or Cx40 using intravital microscopy. Genetic deficiency of SK3, but not of IK1, strongly attenuated dilations to muscular contraction. Similarly, pharmacologic blockade of SK3 by the specific blocker UCL1684 impaired such dilations in wild-type and IK1-deficient mice. In contrast, IK1 was required for acetylcholine-induced dilations. Genetic deficiency of Cx40 also attenuated dilations induced by muscular contraction but not by acetylcholine. These data support the concept that endothelial hyperpolarization through activation of SK3 contributes to exercise hyperemia and the hyperpolarization ascends the vascular tree through gap junctions formed by Cx40 to orchestrate dilation. The differential impact of SK3- and IK1-deficiency on dilations to distinct stimuli suggests stimulus-dependent activation of these endothelial channels.

Gastric Necrosis due to Acute Massive Gastric Dilatation.

PubMed

Aydin, Ibrahim; Pergel, Ahmet; Yucel, Ahmet Fikret; Sahin, Dursun Ali; Ozer, Ender

2013-01-01

Gastric necrosis due to acute massive gastric dilatation is relatively rare. Vascular reasons, herniation, volvulus, acute gastric dilatation, anorexia, and bulimia nervosa play a role in the etiology of the disease. Early diagnosis and treatment are highly important as the associated morbidity and mortality rates are high. In this case report, we present a case of gastric necrosis due to acute gastric dilatation accompanied with the relevant literature.

Gastric Necrosis due to Acute Massive Gastric Dilatation

PubMed Central

Pergel, Ahmet; Yucel, Ahmet Fikret; Sahin, Dursun Ali; Ozer, Ender

2013-01-01

Gastric necrosis due to acute massive gastric dilatation is relatively rare. Vascular reasons, herniation, volvulus, acute gastric dilatation, anorexia, and bulimia nervosa play a role in the etiology of the disease. Early diagnosis and treatment are highly important as the associated morbidity and mortality rates are high. In this case report, we present a case of gastric necrosis due to acute gastric dilatation accompanied with the relevant literature. PMID:23983714

Pre- and post-treatment urinary tract findings in children with nephrogenic diabetes insipidus.

PubMed

Caletti, María Gracia; Balestracci, Alejandro; Di Pinto, Diana

2014-03-01

Nephrogenic diabetes insipidus (NDI) is characterized by the kidney's inability to concentrate urine, which causes intense polyuria that may lead to urinary tract dilation. We report the morphological findings of the urinary tract in ten boys with NDI specifically addressing the presence and changes of urinary tract dilation during treatment. Patients were diagnosed at a median age of 1.6 years (range, 0.16-6.33 years) and treated with a low osmotic diet, hydrochlorothiazide-amiloride and indomethacin, which decreased the diuresis from a median of 10.5 ml/kg/h to 4.4 ml/kg/h (p < 0.001). Three patients showed normal renal ultrasound before treatment until last control, while the remaining seven showed urinary tract dilation. In this second group, dilation was reduced with treatment in four patients and disappeared in the remaining three. Children without dilation or in whom the dilation disappeared were diagnosed and treated earlier than those with persistent dilation (median 1.66 versus 4.45 years, respectively). After a median of 10.4 (range, 2.3-20.3) years of follow-up, no patients showed urological complications. Medical treatment of the disease improved the dilation in all cases, preventing its potential complications. Regardless of the good outcome of our patients, periodic urologic follow-up is recommended in NDI patients.

Endoscopic Balloon Dilatation of Benign Esophageal Stricture—A Nonhazardous Procedure?

PubMed Central

Borgström, Anders; Fork, Frans-Thomas; Lövdahl, Eje

1994-01-01

Balloon dilatation of benign esophageal strictures has been widely used since its introduction. We have performed 224 dilatation procedures in 52 patients. Dilatation was done as an outpatient procedure. Strictures were due to reflux esophagitis in 25 patients, anastomatic stenosis in 6, achalasia in 5, complications of sclerotherapy in 5, corrosive lesions in 3, and long-standing nasogastric intubation in 2. The cause was unknown in 6 cases. The intention was to dilate all strictures up to 20 mm. Three major complications occurred, and one of these patients died. The risk of perforation seems to be higher after repeated procedures than during the first one. PMID:18493348

Natural genetic variation of the cardiac transcriptome in non-diseased donors and patients with dilated cardiomyopathy.

PubMed

Heinig, Matthias; Adriaens, Michiel E; Schafer, Sebastian; van Deutekom, Hanneke W M; Lodder, Elisabeth M; Ware, James S; Schneider, Valentin; Felkin, Leanne E; Creemers, Esther E; Meder, Benjamin; Katus, Hugo A; Rühle, Frank; Stoll, Monika; Cambien, François; Villard, Eric; Charron, Philippe; Varro, Andras; Bishopric, Nanette H; George, Alfred L; Dos Remedios, Cristobal; Moreno-Moral, Aida; Pesce, Francesco; Bauerfeind, Anja; Rüschendorf, Franz; Rintisch, Carola; Petretto, Enrico; Barton, Paul J; Cook, Stuart A; Pinto, Yigal M; Bezzina, Connie R; Hubner, Norbert

2017-09-14

Genetic variation is an important determinant of RNA transcription and splicing, which in turn contributes to variation in human traits, including cardiovascular diseases. Here we report the first in-depth survey of heart transcriptome variation using RNA-sequencing in 97 patients with dilated cardiomyopathy and 108 non-diseased controls. We reveal extensive differences of gene expression and splicing between dilated cardiomyopathy patients and controls, affecting known as well as novel dilated cardiomyopathy genes. Moreover, we show a widespread effect of genetic variation on the regulation of transcription, isoform usage, and allele-specific expression. Systematic annotation of genome-wide association SNPs identifies 60 functional candidate genes for heart phenotypes, representing 20% of all published heart genome-wide association loci. Focusing on the dilated cardiomyopathy phenotype we found that eQTL variants are also enriched for dilated cardiomyopathy genome-wide association signals in two independent cohorts. RNA transcription, splicing, and allele-specific expression are each important determinants of the dilated cardiomyopathy phenotype and are controlled by genetic factors. Our results represent a powerful resource for the field of cardiovascular genetics.

Modern treatment of oesophageal strictures.

PubMed

Eastman, M C; Sali, A

1980-02-09

The results of 185 dilatations of oesophageal strictures with the rigid oesophagoscope are reported. The complication rate was 6%, which included five perforations (2.7%), and one death. The new technique of Eder-Puestow wire-guided dilatation was used in 20 cases without complication. These results, together with other reported experience of Eder-Puestow dilatation, suggest that this technique is superior to that of rigid dilatation on the grounds both of safety and of cost.

The Eyes Have It: Sex and Sexual Orientation Differences in Pupil Dilation Patterns

PubMed Central

Rieger, Gerulf; Savin-Williams, Ritch C.

2012-01-01

Recent research suggests profound sex and sexual orientation differences in sexual response. These results, however, are based on measures of genital arousal, which have potential limitations such as volunteer bias and differential measures for the sexes. The present study introduces a measure less affected by these limitations. We assessed the pupil dilation of 325 men and women of various sexual orientations to male and female erotic stimuli. Results supported hypotheses. In general, self-reported sexual orientation corresponded with pupil dilation to men and women. Among men, substantial dilation to both sexes was most common in bisexual-identified men. In contrast, among women, substantial dilation to both sexes was most common in heterosexual-identified women. Possible reasons for these differences are discussed. Because the measure of pupil dilation is less invasive than previous measures of sexual response, it allows for studying diverse age and cultural populations, usually not included in sexuality research. PMID:22870196

Small Intestinal Submucosa Plug for Closure of Dilated Nephrostomy Tracts: A Pilot Study in Swine

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

Kakizawa, Hideyaki; Conlin, M. J.; Pavcnik, Dusan, E-mail: pavcnikd@ohsu.edu

2010-06-15

The aim of this study was to evaluate efficacy of a plug made of small intestinal submucosa (SIS) for closure of dilated nephrostomy tract in the kidney after nephroscopy. Ten kidneys in 5 swine had nephrostomy tracts dilated up to 8 mm. The SIS plug was placed into the dilated renal cortex under nephroscopic control. Follow-up arteriograms, retrograde pyelograms, and macroscopic and histologic studies at 24 h (n = 4), 6 weeks (n = 2), and 3 months (n = 4) were performed to evaluate the efficacy of the plug. The SIS plug effectively closed the dilated nephrostomy tract. Follow-upmore » studies showed minimal changes of the kidneys, except for 1 small infarction, regarding inflammatory and foreign-body reactions and progressive scarring of the SIS. SIS plug is effective for occlusion of dilated nephrostomy tract after nephroscopy. Its efficacy should be compared with other therapeutic options.« less

The pressure-dilatation correlation in compressible flows

NASA Technical Reports Server (NTRS)

Sarkar, S.

1992-01-01

Simulations of simple compressible flows have been performed to enable the direct estimation of the pressure-dilatation correlation. The generally accepted belief that this correlation may be important in high-speed flows has been verified by the simulations. The pressure-dilatation correlation is theoretically investigated by considering the equation for fluctuating pressure in an arbitrary compressible flow. This leads to the isolation of a component of the pressure-dilatation that exhibits temporal oscillations on a fast time scale. Direct numerical simulations of homogeneous shear turbulence and isotropic turbulence show that this fast component has a negligible contribution to the evolution of turbulent kinetic energy. Then, an analysis for the case of homogeneous turbulence is performed to obtain a formal solution for the nonoscillatory pressure-dilatation. Simplifications lead to a model that algebraically relates the pressure-dilatation to quantities traditionally obtained in incompressible turbulence closures. The model is validated by direct comparison with the simulations.

Exploring full cervical dilatation caesarean sections-A retrospective cohort study.

PubMed

Corry, Edward M A; Ramphul, Meenakshi; Rowan, Ann M; Segurado, Ricardo; Mahony, Rhona M; Keane, Declan P

2018-05-01

The rate of caesarean sections at full cervical dilatation with their high risk of morbidity continues to rise mirroring the overall increase in caesarean section rates internationally. The objectives of this study were to determine the rate of full dilatation caesarean section in a tertiary referral unit and evaluate key labour, maternal and fetal factors potentially linked to those deliveries. We also assessed maternal and fetal morbidity at full dilatation sections. Where possible, these were compared with successful operative vaginal deliveries carried out in theatre to determine key differences. Retrospective cohort study. We reviewed the rate of full dilatation caesarean section over a 10-year period. We analysed deliveries (caesarean sections or operative vaginal deliveries) in single cephalic pregnancies ≥34 weeks with contemporaneously collected data from our unit's electronic database for 2015. The rate of full dilatation caesarean section increased by over a third in the ten-year period (56/6947 (0.80%) vs 92/7378 (1.24%), p = 0.01). Of 84 full dilatation caesarean sections who met the inclusion criteria, 63 (75%) were nulliparous and the mean maternal age was 33 (±5) years. Oxytocin was used in the second stage in less than half of second stage caesarean sections (22 out of a recorded 57, 38.6%). There were more fetal head malposition (occipito-posterior, or occipito-transverse) at full dilatation caesarean section compared to successful operative vaginal deliveries (41/46 (89.1%) vs 2/21 (9.5), p < 0.001). The rate of significant postpartum haemorrhage (defined as estimated blood loss ≥1000 ml) was similar in both full dilatation caesarean section and operative vaginal deliveries. There was no difference in the mean birthweight at full dilatation caesarean sections compared to operative vaginal delivery (3.88 kg (2.80-5.33 kg) vs 3.48 kg (1.53-4.40 kg)). There was no difference in neonatal morbidity. Fetal head malposition is associated with a higher risk of full dilatation caesarean section. Interestingly, maternal and fetal morbidity were similar between full dilatation caesarean sections and anticipated difficult operative vaginal deliveries carried out in theatre. The management of labour in terms of the decision to use oxytocin judiciously in hope of correcting inefficient uterine contractions and continuous labour ward training, particularly the diagnosis of malposition and its correction may be beneficial in reducing the rate of full dilation caesarean sections. Copyright © 2018 Elsevier B.V. All rights reserved.

Office Dilation of the Female Urethra: A Quality of Care Problem in the Field of Urology

PubMed Central

Santucci, Richard A.; Payne, Christopher K.; Saigal, Christopher S.

2008-01-01

Purpose: Historically dilation of the female urethra was thought to be of value in the treatment of a variety of lower urinary tract symptoms. Subsequent work has more accurately classified these complaints as parts of various diseases or syndromes in which scant data exist to support the use of dilation. Yet Medicare reimbursement for urethral dilation remains generous and we describe practice patterns regarding female urethral dilation to characterize a potential quality of care issue. Materials and Methods: Health care use by females treated with urethral dilation was compiled using a complementary set of databases. Data sets were examined for relevant inpatient, outpatient and emergency room services for women of all ages. Results: Female urethral dilation is common (929 per 100,000 patients) and is performed almost as much as treatment for male urethral stricture disease. Approximately 12% of these patients are subjected to costly studies such as retrograde urethrography. The overall national costs for treatment exceed $61 million per year and have increased 10% to 17% a year since 1994. A diagnosis of female urethral stricture increases health care expenditures by more than $1,800 per individual per year in insured populations. Conclusions: Urethral dilation is still common despite the fact that true female urethral stricture is an uncommon entity. This scenario is likely secondary to the persistence of the mostly discarded practice of dilating the unstrictured female urethra for a wide variety of complaints despite the lack of data suggesting that it improves lower urinary tract symptoms. PMID:18804232

A novel technique of concurrent esophagoscopy and transgastrostomy gastroscopy to dilate a completely obstructed distal esophageal stricture in a child following fundoplication.

PubMed

Isaiah, J H; Jones, A B; Lalor, E; Evans, M; Dhunno, I; Huynh, H Q

2005-08-01

We report a successful dilation of a completely obstructed distal esophageal stricture in a 4-year-old boy with combined immune deficiency syndrome, at 2 and half years after fundoplication and gastrostomy tube insertion. Barium studies and esophagoscopy had revealed complete obstruction of the lower esophagus. Transgastrostomy gastroscopy demonstrated a pinhole lumen through the fundoplication wrap; a guide wire was passed into the esophagus; and the stricture was dilated with Savary dilators. We presumed that the stricture was secondary to chronic esophagitis. The stricture was identified and successfully dilated using a novel technique of concurrent esophagoscopy and transgastrostomy gastroscopy.

Aortic dilatation in Turner syndrome: the role of MRI in early recognition.

PubMed

Chalard, François; Ferey, Solène; Teinturier, Cécile; Kalifa, Gabriel

2005-03-01

Aortic dilatation and dissection are rare but important complications of Turner syndrome that increase the risk of sudden death in young patients. To assess the value of aortic MRI in patients with Turner syndrome; in particular to demonstrate early aortic dilatation. A total of 21 patients with Turner syndrome underwent MRI of the thoracic aorta with measurement of vessel diameter at four levels. Measurements were normal for age in 15 cases, two patients presented with values at the upper limit of normal and four had obvious dilatation of the ascending aorta. All were symptom free. MRI allows the non-invasive demonstration of early aortic dilatation, which may lead to earlier surgery in asymptomatic individuals.

Novel use of tissue expander for dilation of oropharyngeal stenosis.

PubMed

Banerjee, Debdeep; Wang, James C; Demke, Joshua C

2014-11-01

Naso/oropharyngeal stenoses are uncommon surgical complications. We present a child having undergone previous adenoidectomy without complication who developed naso/oropharyngeal scarring after subsequent tonsillectomy. She presented with nasal obstruction and frequent gasping at night worrisome for obstructive sleep apnea. Scar was initially excised and the defect allografted. Conventional esophageal dilators were undersized, and ultimately a tissue expander was used intraoperatively as a balloon dilator. The patient's symptoms and sleep apnea resolved. We found use of a tissue expander as a balloon dilator to be at least minimally effective in dilating the oropharynx when all other methods at our disposal proved ineffective. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Duodenal adenocarcinoma presenting as a mass with aneurismal dilatation.

PubMed

Mama, Nadia; Ben Slama, Aïda; Arifa, Nadia; Kadri, Khaled; Sriha, Badreddine; Ksiaa, Mehdi; Jemni, Hela; Tlili-Graiess, Kalthoum

2014-01-01

Duodenal adenocarcinoma is frequent. Aneurysmal dilatation of the small bowel is reported to be a lymphoma characteristic imaging finding. A 57-year-old male was found to have a duodenal adenocarcinoma with aneurismal dilatation on imaging which is an exceptional feature. On laparotomy, the wall thickening of the dilated duodenum extended to the first jejunal loop, with multiple mesenteric lymph nodes and ascites. Segmental palliative resection with gastro-entero-anastomosis was done. Histopathology revealed a moderately differentiated adenocarcinoma with neuro-endocrine differentiation foci. Wide areas of necrosis and vascular emboli were responsible for the radiological feature of the dilated duodenum with wall thickening. Copyright © 2014 Elsevier Inc. All rights reserved.

Dilation of the olfactory bulb cavity concurrent with hydrocephalus in four small breed dogs

PubMed Central

Kim, Jung-Hyun; Jeon, Hyo-Won; Woo, Eung-Je

2009-01-01

Four small breed dogs were admitted with seizures. Magnetic resonance imaging (MRI) of the brain revealed dilation of the olfactory bulb cavity as well as enlargement of the lateral ventricles. These findings demonstrate that dilation of the olfactory bulb cavity can occur concurrent with hydrocephalus. This is the first description of the clinical and MRI features of dilation of the olfactory bulb cavity concurrent with hydrocephalus in dogs. PMID:19461216

Dilated cardiomyopathy and sinoatrial dysfunction in an Estrela mountain dog.

PubMed

Lobo, Luis; Pinheiro-Vieira, António; Gomes, João L; Canada, Nuno; Ribeiro, Lenio; Costa, Paulo D; Oliveira, Pedro; Bussadori, Claudio

2012-01-01

A 1 yr old male Estrela mountain dog was evaluated as a part of a screening program for dilated cardiomyopathy. The dog came from a family with a history of dilated cardiomyopathy but was asymptomatic. Occult dilated cardiomyopathy and sino-atrial dysfunction were diagnosed based on echocardiography and electrocardiography. These two disorders may be associated given that related dogs have been diagnosed with the same disorders. The dog has remained asymptomatic for 4 years following initial evaluation.

Muscles involved in naris dilation and nose motion in rat

PubMed Central

Deschênes, Martin; Haidarliu, Sebastian; Demers, Maxime; Moore, Jeffrey; Kleinfeld, David; Ahissar, Ehud

2016-01-01

In a number of mammals muscle dilator nasi (naris) is known as a muscle that reduces nasal airflow resistance by dilating the nostrils. Here we show that in rats the tendon of this muscle inserts into the aponeurosis above the nasal cartilage. Electrical stimulation of this muscle lifts the nose and deflects it sideway towards the side of stimulation, but does not change the size of the nares. In the head-fixed alert rat, electromyographic activity of muscle dilator nasi is tightly coupled to nose motion, not to opening of the nares. Yet, contraction of muscle dilator nasi occurs during the pre-inspiratory phase of the respiratory cycle, suggesting a role in sniffing and sampling odorants. We also show that opening of the nares results from contraction of pars maxillaris profunda of the muscle nasolabialis profundus. This muscle attaches to the outer wall of the nasal cartilage and to the plate of the mystacial pad. Contraction of this muscle exerts a dual action: it pulls the lateral nasal cartilage outwardly, thus dilating the naris, and it drags the plate of the mystacial pad rostralward, provoking a slight retraction of the whiskers. On the basis of these results, we propose that muscle dilator nasi of the rat be renamed muscle deflector nasi, and that pars maxillaris profunda of the muscle nasolabialis profundus be named muscle dilator nasi. PMID:25257748

The induction of nitric oxide-mediated relaxation of human isolated pulmonary arteries by PACAP

PubMed Central

Cardell, Lars Olaf; Hjert, Ola; Uddman, Rolf

1997-01-01

The effects of pituitary adenylate cyclase-activating peptide (PACAP) and vasoactive intestinal peptide (VIP) were analysed in human isolated circular segments of pulmonary arteries. Guinea-pig pulmonary arteries were used for comparison. The responses obtained were analysed in relation to the vascular endothelium and the nitric oxide (NO) synthase inhibitor NG-monomethyl L-arginine (L-NMMA).PACAP and VIP induced concentration-dependent relaxations of precontracted pulmonary arteries. The maximal dilator response (Imax,%) and the potency (pEC50 value) were the same for both peptides, and there were no differences in the effects obtained on human and guinea-pig segments. PACAP and VIP were both more potent that acetylcholine (ACh).Removal of the vascular endothelium abolished the PACAP induced dilator response in pulmonary arteries from both species. The VIP induced dilatation was unaffected, whereas the response to ACh was abolished. L-NMMA given before PACAP inhibited the dilatation. Furthermore, L-NMMA also reversed the dilatation already induced by PACAP and excess concentrations of L-arginine restored the dilator response of the L-NMMA treated arteries.PACAP is a potent dilator of human pulmonary arteries. Although the dilator effect seems to be similar in amplitude to the one induced by VIP, the present results suggest differences in the underlying mechanisms of action (endothelium-dependency) between the two peptides. PMID:9134222

Is It Possible to Increase Flap Viability by Hydrostatic Dilation?: An Experimental Study in the Rat Abdominal Fasciocutaneous Flap Model.

PubMed

Sahin, Cihan; Aysal, Bilge Kagan; Ergun, Ozge

2016-08-01

Ergun et al previously demonstrated the efficacy of hydrostatic dilation in a TRAM flap model in an experimental study. We investigated the effect of hydrostatic dilation on a fasciocutaneous flap model. Eighteen female Wistar rats were equally divided into 3 groups, of which 1 served as a control. In the second, the abdominal fasciocutaneous flap surgical delay procedure was performed by division of the left superficial inferior epigastric (SIE) vessels. In the third, hydrostatic dilation was performed on the left SIE artery and vein, with a mean pressure of 300 mm Hg, while elevating the flap on the right-sided SIE pedicle. The groups were compared by microangiography and by the survival ratio of abdominal flaps 7 days after elevation. The mean (SD) flap necrosis rates were as follows: control group, 44.75% (4.31%); delay group, 33.32% (7.11%); and hydrostatic dilation group, 32.51% (5.03%). There was a significant difference between the control group and the other 2 groups (P < 0.05). There was no difference between the delay and hydrostatic dilation groups with respect to surface area necrosis. The microangiographies showed remarkable increased vascularity in the delay and hydrostatic dilation groups. Hydrostatic dilation is a new method of enhancing flap viability that could be used in clinical cases in place of surgical delay once further studies and clinical trials are completed.

Effect of acute gastric dilatation on gastric myoelectic and motor activity in dogs.

PubMed

Hall, J A; Solie, T N; Seim, H B; Twedt, D C

1999-05-01

To investigate the effects of experimentally induced acute gastric dilatation on electrical and mechanical activities of the stomach in dogs. 7 healthy dogs. Electrodes and strain-gauge force transducers were implanted on the serosal surface of the antrum and pylorus. Eight days later, baseline gastric electrical and contractile activities were recorded. The dogs were anesthetized and mechanically ventilated to maintain normocapnia while the stomach was distended (intragastric pressure, 30 mm Hg) for 180 minutes, using a thin compliant bag. Gastric electrical and contractile activities were recorded again on days 1 and 10 after dilatation. Recordings were analyzed to determine gastric slow-wave frequency, slow-wave dysrhythmia, propagation velocity of slow-waves, coupling of contractions to slow waves, motility index on the basis of relative contractile amplitudes, and onset of contractions after a standardized meal. Electrical or contractile activities were not significantly different 18 hours after acute gastric dilatation (day 1). Arrhythmias were evident before and after gastric dilatation in dogs from which food was withheld and in dogs after consumption of a meal. Variables for assessing gastric electrical and contractile activities were unaffected 18 hours after acute gastric dilatation. Analysis of results of this study indicated that altered electrical and contractile activities in dogs with short-term gastric dilatation are not likely to be secondary to the process of acute gastric dilatation.

The Esophageal Anastomotic Stricture Index (EASI) for the management of esophageal atresia.

PubMed

Sun, Linda Yi-Chan; Laberge, Jean-Martin; Yousef, Yasmine; Baird, Robert

2015-01-01

Anastomotic stricture is the most common complication following repair of esophageal atresia. An Esophageal Anastomotic Stricture Index (EASI) based on the postoperative esophagram may identify patients at high risk of stricture formation. Digital images of early postoperative esophagrams of patients undergoing EA repair from 2005 to 2013 were assessed. Demographics and outcomes including dilations were prospectively collected. Upper (U-EASI) and lower (L-EASI) pouch ratios were generated using stricture diameter divided by maximal respective pouch diameter. Score performances were evaluated with area under the receiver operator curves (AUC) and the Fisher's exact test for single and multiple (>3) dilatations. Interrater agreement was evaluated using the intraclass correlation coefficient (ICC). Forty-five patients had esophagrams analyzed; 28 (62%) required dilatation and 19 received >3 (42%). U-EASI and L-EASI ratios ranged from 0.17 to 0.70, with L-EASI outperforming the U-EASI as follows: L-EASI AUC: 0.66 for a single dilatation, 0.65 for >3 dilatations; U-EASI AUC: 0.56 for a single dilatation, 0.67 for >3 dilatations. All patients with an L-EASI ratio of ≤0.30 (n=8) required multiple esophageal dilatations, p=0.0006. The interrater ICC was 0.87. The EASI is a simple, reproducible tool to predict the development and severity of anastomotic stricture after esophageal atresia repair and can direct postoperative surveillance. Copyright © 2015 Elsevier Inc. All rights reserved.

Constraining friction, dilatancy and effective stress with earthquake rates in the deep crust

NASA Astrophysics Data System (ADS)

Beeler, N. M.; Thomas, A.; Burgmann, R.; Shelly, D. R.

2015-12-01

Similar to their behavior on the deep extent of some subduction zones, families of recurring low-frequency earthquakes (LFE) within zones of non-volcanic tremor on the San Andreas fault in central California show strong sensitivity to stresses induced by the tides. Taking all of the LFE families collectively, LFEs occur at all levels of the daily tidal stress, and are in phase with the very small, ~200 Pa, shear stress amplitudes while being uncorrelated with the ~2 kPa tidal normal stresses. Following previous work we assume LFE sources are small, persistent regions that repeatedly fail during shear within a much larger scale, otherwise aseismically creeping fault zone and that the correlation of LFE occurrence reflects modulation of the fault creep rate by the tidal stresses. We examine the predictions of laboratory-observed rate-dependent dilatancy associated with frictional slip. The effect of dilatancy hardening is to damp the slip rate, so high dilatancy under undrained pore pressure reduces modulation of slip rate by the tides. The undrained end-member model produces: 1) no sensitivity to the tidal normal stress, as first suggested in this context by Hawthorne and Rubin [2010], and 2) fault creep rate in phase with the tidal shear stress. Room temperature laboratory-observed values of the dilatancy and friction coefficients for talc, an extremely weak and weakly dilatant material, under-predict the observed San Andreas modulation at least by an order of magnitude owing to too much dilatancy. This may reflect a temperature dependence of the dilatancy and friction coefficients, both of which are expected to be zero at the brittle-ductile transition. The observed tidal modulation constrains the product of the friction and dilatancy coefficients to be at most 5 x 10-7 in the LFE source region, an order of magnitude smaller than observed at room temperature for talc. Alternatively, considering the predictions of a purely rate-dependent talc friction would constrain the ambient effective normal stress to be no more than 40 kPa. In summary, for friction models that have both rate-dependent strength and dilatancy, the observations require intrinsic weakness, low dilatancy, and lithostatic pore fluid pressures.

Salivary gland enlargement during oesophageal stricture dilatation.

PubMed Central

Martin, D.

1980-01-01

A case of recurrent salivary gland enlargement occurring during fibreoptic oesophagoscopy and oesophageal stricture dilatation with Eder-Puestow dilators is described. The genesis of this condition is discussed and its transient and usually benign nature emphasized. Images Fig. 1 PMID:7393809

[Development and evaluation of a prosthetic valved conduit dilated by percutaneous approach: experimental study in the lamb].

PubMed

Boudjemline, Y; Laborde, F; Pineau, E; Mollet, A; Abadir, S; Bonhoeffer, P; Bonnet, D; Sidi, D

2006-05-01

This study was undertaken to develop a dilated valved conduit for reconstruction of the right ventricular outflow tract in the animal. The conduits were made by sewing a valved tube (Medtronic Inc) inside a vascular stent (Numed Inc). After preparation, they were inserted surgically in five lambs. The conduits were then dilated 6 weeks and 3 months after their implantation. Before sacrificing the animals at 3 months, a 22 mm valved stent was implanted percutaneously inside the surgical conduits. One animal died suddenly due to kinking of the conduit. Balloon dilatation was performed in the surviving animals. The first dilatation only had a modest impact on valvular function but it was much aggravated after the second dilatation. A valved stent was successfully inserted percutaneously. At sacrifice, all the conduits were completely engulfed in an intense fibrosis. In conclusion, a valved biological conduit for reconstruction of the right ventricular ejection tract has been developed and can be dilated sequentially to follow growth. The new product could have an important role to play in the management of congenital malformations involving the right ventricular outflow tract.

Endoscopic minor papilla balloon dilation for the treatment of symptomatic pancreas divisum.

PubMed

Yamamoto, Natsuyo; Isayama, Hiroyuki; Sasahira, Naoki; Tsujino, Takeshi; Nakai, Yousuke; Miyabayashi, Koji; Mizuno, Suguru; Kogure, Hirofumi; Sasaki, Takashi; Hirano, Kenji; Tada, Minoru; Koike, Kazuhiko

2014-08-01

A subpopulation of patients with pancreas divisum experience symptomatic events such as recurrent acute pancreatitis and chronic pancreatitis. Minor papilla sphincterotomy has been reported as being an effective treatment. The aim of this study was to evaluate the safety and efficacy of endoscopic balloon dilation for the minor papilla. Between 2000 and 2012, 16 patients were retrospectively included in this study. After endoscopic balloon dilation for the minor papilla was received, a pancreatic stent or a nasal pancreatic drainage catheter was placed for 1 week. If a stricture or obstruction was evident, it was treated with balloon dilation followed by long-term stent placement (1 year). When an outflow of pancreatic juice was disturbed by a pancreatic stone, endoscopic stone extraction was performed. Balloon dilation and stent placement were achieved and were successful in all the cases (16/16; 100%). Clinical improvement was achieved in 7 (84.7%) of the 9 patients with recurrent acute pancreatitis and in 6 (85.7%) of the 7 patients with chronic pancreatitis. Early complications were observed in 1 (6.3%) patient. Pancreatitis or bleeding related to balloon dilation was not observed. Endoscopic balloon dilation for the minor papilla is feasible for the management of symptomatic pancreas divisum.

Long-term effect of urethral dilatation and internal urethrotomy for urethral strictures.

PubMed

Veeratterapillay, Rajan; Pickard, Rob S

2012-11-01

Urethral dilatation and direct visual internal urethrotomy (DVIU) are widely used minimally invasive options to manage men with urethral strictures. Advances in open urethroplasty with better long-term cure rates have fuelled the continuing debate as to which treatment is best for primary and recurrent urethral strictures. We reviewed recent literature to identify contemporary practice of urethral dilatation and DVIU and the long-term outcome of these procedures. Systematic literature search for the period January 2010 to December 2011 showed that urethral dilatation and DVIU remain frequently used treatment options as confirmed by surveys of urologists in the USA and the Netherlands. Multiple reports of laser DVIU confirm the safety of this approach but long-term data were lacking. Stricture free rates from urethra dilatation and DVIU vary from 10 to 90% at 12 months, although adjunctive intermittent self-dilatation can reduce time to recurrence. Although quality-of-life benefit appears good in the short term, repeated procedures may harm sexual function in the long-term. Urethral dilatation and DVIU remain widely used in urethral stricture management but high-level comparative evidence of benefit and harms against urethroplasty in the short and long-term is still lacking.

Dilatational band formation in bone

PubMed Central

Poundarik, Atharva A.; Diab, Tamim; Sroga, Grazyna E.; Ural, Ani; Boskey, Adele L.; Gundberg, Caren M.; Vashishth, Deepak

2012-01-01

Toughening in hierarchically structured materials like bone arises from the arrangement of constituent material elements and their interactions. Unlike microcracking, which entails micrometer-level separation, there is no known evidence of fracture at the level of bone’s nanostructure. Here, we show that the initiation of fracture occurs in bone at the nanometer scale by dilatational bands. Through fatigue and indentation tests and laser confocal, scanning electron, and atomic force microscopies on human and bovine bone specimens, we established that dilatational bands of the order of 100 nm form as ellipsoidal voids in between fused mineral aggregates and two adjacent proteins, osteocalcin (OC) and osteopontin (OPN). Laser microdissection and ELISA of bone microdamage support our claim that OC and OPN colocalize with dilatational bands. Fracture tests on bones from OC and/or OPN knockout mice (OC−/−, OPN−/−, OC-OPN−/−;−/−) confirm that these two proteins regulate dilatational band formation and bone matrix toughness. On the basis of these observations, we propose molecular deformation and fracture mechanics models, illustrating the role of OC and OPN in dilatational band formation, and predict that the nanometer scale of tissue organization, associated with dilatational bands, affects fracture at higher scales and determines fracture toughness of bone. PMID:23129653

Nasal Dilators (Breathe Right Strips and NoZovent) for Snoring and OSA: A Systematic Review and Meta-Analysis

PubMed Central

Malu, Omojo O.; Kram, Yoseph A.; Song, Sungjin A.; Tolisano, Anthony M.; Kushida, Clete A.

2016-01-01

Objective. To systematically review the international literature for studies evaluating internal (NoZovent) and external (Breathe Right Strips) nasal dilators as treatment for obstructive sleep apnea (OSA). Study Design. Systematic review with meta-analysis. Methods. Four databases, including PubMed/MEDLINE, were searched through September 29, 2016. Results. One-hundred twelve studies were screened, fifty-eight studies were reviewed, and fourteen studies met criteria. In 147 patients, the apnea-hypopnea index (AHI) was reported, and there was an improvement from a mean ± standard deviation (M ± SD) of 28.7 ± 24.0 to 27.4 ± 23.3 events/hr, p value 0.64. There was no significant change in AHI, lowest oxygen saturation, or snoring index in OSA patients when using nasal dilators. However, a subanalysis demonstrated a slight reduction in apnea index (AI) with internal nasal dilators (decrease by 4.87 events/hr) versus minimal change for external nasal dilators (increase by 0.64 events/hr). Conclusion. Although nasal dilators have demonstrated improved nasal breathing, they have not shown improvement in obstructive sleep apnea outcomes, with the exception of mild improvement in apnea index when internal nasal dilators were used. PMID:28070421

Congenital duodenal web: successful management with endoscopic dilatation

PubMed Central

Poddar, Ujjal; Jain, Vikas; Yachha, Surender Kumar; Srivastava, Anshu

2016-01-01

Background and study aims: Congenital duodenal web (CDW) is an uncommon cause of duodenal obstruction and endoscopic balloon dilatation has been reported in just eight pediatric cases to date. Here we are reporting three cases of CDW managed successfully with balloon dilatation. Cases and methods: In 2014 we diagnosed three cases of CDW on the basis of typical radiological and endoscopic findings. Endoscopic balloon dilatation was done under conscious sedation with a through-the-scope controlled radial expansion (CRE) balloon. Results: All three children presented late (median age 8 [range 2 – 9] years) with bilious vomiting, upper abdominal distension, and failure to thrive. One of them had associated Down syndrome and another had horseshoe kidney. In all cases, CDW was observed in the second part of the duodenum beyond the ampulla, causing partial duodenal obstruction. After repeated endoscopic dilatation (2 – 4 sessions), all three patients became asymptomatic. None of the patients experienced complications after balloon dilatation. Conclusions: Duodenal diaphragm should be suspected in patients with abdominal distension with bilious vomiting, even in relatively older children. Endoscopic balloon dilatation is a simple and effective method of treating this condition. PMID:27004237

Probabilities of Dilating Vesicoureteral Reflux in Children with First Time Simple Febrile Urinary Tract Infection, and Normal Renal and Bladder Ultrasound.

PubMed

Rianthavorn, Pornpimol; Tangngamsakul, Onjira

2016-11-01

We evaluated risk factors and assessed predicted probabilities for grade III or higher vesicoureteral reflux (dilating reflux) in children with a first simple febrile urinary tract infection and normal renal and bladder ultrasound. Data for 167 children 2 to 72 months old with a first febrile urinary tract infection and normal ultrasound were compared between those who had dilating vesicoureteral reflux (12 patients, 7.2%) and those who did not. Exclusion criteria consisted of history of prenatal hydronephrosis or familial reflux and complicated urinary tract infection. The logistic regression model was used to identify independent variables associated with dilating reflux. Predicted probabilities for dilating reflux were assessed. Patient age and prevalence of nonEscherichia coli bacteria were greater in children who had dilating reflux compared to those who did not (p = 0.02 and p = 0.004, respectively). Gender distribution was similar between the 2 groups (p = 0.08). In multivariate analysis older age and nonE. coli bacteria independently predicted dilating reflux, with odds ratios of 1.04 (95% CI 1.01-1.07, p = 0.02) and 3.76 (95% CI 1.05-13.39, p = 0.04), respectively. The impact of nonE. coli bacteria on predicted probabilities of dilating reflux increased with patient age. We support the concept of selective voiding cystourethrogram in children with a first simple febrile urinary tract infection and normal ultrasound. Voiding cystourethrogram should be considered in children with late onset urinary tract infection due to nonE. coli bacteria since they are at risk for dilating reflux even if the ultrasound is normal. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

The effect of bone tunnel dilation versus extraction drilling on the initial fixation strength of press-fit anterior cruciate ligament reconstruction.

PubMed

Dargel, Jens; Schmidt-Wiethoff, Rüdiger; Brüggemann, Gert-Peter; Koebke, Jürgen

2007-11-01

Serial dilation of the bone tunnel has been reported to create a tighter graft-tunnel fit. It was hypothesized that a serial dilation of the femoral bone tunnel would increase the initial fixation strength in press-fit anterior cruciate ligament (ACL) reconstructive surgery. Initial fixation strength of the femoral press-fit fixation technique was investigated in 72 porcine specimens in an ex vivo study by varying the femoral tunnel preparation technique. Extraction-drilling, tunnel dilation by 1 mm and dilation by 2.5 mm were assessed. Initial fixation strength of press-fit fixated patellar tendon-bone grafts was tested within each preparation group conducting a single cycle (and cyclic) load to failure protocol. The resulting tunnel diameter and the porcine femoral bone mineral density were determined using microradiographs and peripheral quantitative CT scans, respectively. Dilating a previously extraction-drilled femoral bone tunnel by 1 mm significantly enhances initial press-fit fixation strength in both single cycle and cyclic load to failure testing when compared to extraction-drilling and tunnel dilation by 2.5 mm. Due to an initial spring-back effect the resulting diameter of the femoral tunnel was underestimated by 3.3% with drilling and 6.7 and 12.2% with dilation by 1 and 2.5 mm, respectively. Volumetric trabecular bone mineral density at the site corresponding to the area of tunnel placement averaged 318 mg/cm(3). Dilating a femoral tunnel that is underdrilled by 1 mm appears to be a reasonable technical procedure in order to enhance initial fixation strength of press-fit ACL graft fixation.

Comparing the 12-month patency of low- versus high-pressure dilation in failing arteriovenous fistulae: A prospective multicenter trial (YOROI study).

PubMed

Wakamoto, Koki; Doi, Shigehiro; Nakashima, Ayumu; Kawai, Toru; Kyuden, Yasufumi; Naito, Takayuki; Asai, Mariko; Takahashi, Shunsuke; Murakami, Masaaki; Masaki, Takao

2018-03-01

This study was performed to investigate the effect of the balloon dilation pressure on the 12-month patency rate in patients with failed arteriovenous fistulas undergoing hemodialysis. In this multicenter, prospective, randomized trial, the 4-mm-diameter YOROI balloon was used for dilation of stenotic lesions. The balloons were inflated to a pressure of 8 atm (low-pressure group) or 30 atm to achieve complete expansion (high-pressure group). The 12-month patency rate after balloon angioplasty was analyzed by the Kaplan-Meier method and log-rank test and/or a Cox proportional hazard model. We also investigated the dilation pressure required to achieve complete expansion in the high-pressure group. In total, 71 patients were enrolled and allocated to either the low-pressure group (n = 34) or the high-pressure group (n = 37). The 12-month patency rates showed no significant difference between the low- and high-pressure groups (47% and 49%, respectively; p = 0.87). In the low-pressure group, the patency rate was not different between patients with complete dilation and residual stenosis (44% and 50%, respectively; p = 0.87). The Cox proportional hazard model revealed that the 12-month patency rate was associated with the stenosis diameter (hazard ratio 0.36; p = 0.001) and the presence of diabetes (hazard ratio 0.33; p = 0.018). Finally, the pressure required to achieve complete dilation was ≤20 atm in 76% of patients and ≤30 atm in 97% of patients. One patient required a dilation pressure of >30 atm. The patency rate does not differ between low-pressure dilation and high-pressure dilation.

The evolution of fracture surface roughness and its dependence on slip

NASA Astrophysics Data System (ADS)

Wells, Olivia L.

Under effective compression, impingement of opposing rough surfaces of a fracture can force the walls of the fracture apart during slip. Therefore, a fracture's surface roughness exerts a primary control on the amount of dilation that can be sustained on a fracture since the opposing surfaces need to remain in contact. Previous work has attempted to characterize fracture surface roughness through topographic profiles and power spectral density analysis, but these metrics describing the geometry of a fracture's surface are often non-unique when used independently. However, when combined these metrics are affective at characterizing fracture surface roughness, as well as the mechanisms affecting changes in roughness with increasing slip, and therefore changes in dilation. These mechanisms include the influence of primary grains and pores on initial fracture roughness, the effect of linkage on locally increasing roughness, and asperity destruction that limits the heights of asperities and forms gouge. This analysis reveals four essential stages of dilation during the lifecycle of a natural fracture, whereas previous slip-dilation models do not adequately address the evolution of fracture surface roughness: (1) initial slip companied by small dilation is mediated by roughness controlled by the primary grain and pore dimensions; (2) rapid dilation during and immediately following fracture growth by linkage of formerly isolated fractures; (3) wear of the fracture surface and gouge formation that minimizes dilation; and (4) between slip events cementation that modifies the mineral constituents in the fracture. By identifying these fundamental mechanisms that influence fracture surface roughness, this new conceptual model relating dilation to slip has specific applications to Enhanced Geothermal Systems (EGS), which attempt to produce long-lived dilation in natural fractures by inducing slip.

Endovascular Treatment for Fusiform Dilation of Internal Carotid Artery Following Craniopharyngioma Resection: A Case Illustration.

PubMed

Li, Qiang; Wang, Chaohua; Xu, Jianguo; You, Chao

2015-09-01

Fusiform dilation of the internal carotid artery complicates aggressive craniopharyngioma resection and occurs mainly in children. We report a case to describe the availability of endovascular treatment for this rare entity. A 13-year-old boy presented with headache for 2 years after resection of craniopharyngioma. A fusiform dilation of the right carotid artery was found and was coiled using stent-assisted technique. Follow-up showed satisfactory outcome and disappearance of headache. To our knowledge, this is the first report regarding endovascular treatment for fusiform dilation of the internal carotid artery after craniopharyngioma resection. Stent-assisted coiling is a useful approach for fusiform dilation of the internal carotid artery following craniopharyngioma surgery. © The Author(s) 2014.

Outlook with conservative treatment of peptic oesophageal stricture.

PubMed Central

Ogilvie, A L; Ferguson, R; Atkinson, M

1980-01-01

In order to assess the outlook for patients with peptic oesophageal strictures treated by Eder Puestow dilatation at fibreoptic endoscopy, 50 patients were followed up for periods ranging from nine months to four years. Twenty patients (40%) required only a single dilatation, and the remaining 30 (60%) required multiple dilatations. The frequency of dilatation tended to decrease with time. There was one death attributable to the procedure. Two patients developed an adenocarcinoma at the site of the stricture. We conclude that conservative management of peptic oesophageal stricture combining the use of dilatation at fibreoptic endoscopy with medical measures to control gastro-oesophageal reflux offers a relatively safe means of providing symptomatic relief, maintaining nutrition, and allowing the patient an acceptable quality of life. PMID:7364314

21 CFR 876.5470 - Ureteral dilator.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ureteral dilator. 876.5470 Section 876.5470 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5470 Ureteral dilator. (a...

21 CFR 876.5520 - Urethral dilator.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Urethral dilator. 876.5520 Section 876.5520 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5520 Urethral dilator. (a...

21 CFR 876.5365 - Esophageal dilator.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Esophageal dilator. 876.5365 Section 876.5365 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5365 Esophageal dilator. (a...

21 CFR 876.5470 - Ureteral dilator.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ureteral dilator. 876.5470 Section 876.5470 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5470 Ureteral dilator. (a...

Incidence and management of benign anastomotic stricture after cervical oesophagogastrostomy.

PubMed

Pierie, J P; de Graaf, P W; Poen, H; van der Tweel, I; Obertop, H

1993-04-01

Benign anastomotic stricture after transhiatal oesophagectomy and gastric tube reconstruction constitutes a major problem. From August 1988 to April 1991, 81 patients were followed after cervical oesophagogastrostomy. Twenty-four patients (30 per cent) developed a benign anastomotic stricture 3-23 (median 8) weeks after operation. Poor vascularization of the gastric tube, determined during operation, and postoperative anastomotic leakage were statistically significant risk factors for stricture formation. Symptoms related to stricture were often typical and were confirmed by endoscopy and/or radiography. Radiography did not yield information additional to that obtained from endoscopy. Strictures were treated in the outpatient clinic by dilatation with Savary dilators. Repeated dilatation completely alleviated dysphagia in 20 of the 24 patients (83 per cent). In ten patients dilatations could be discontinued after a median of 8 (range 1-17) sessions. Dilatation was continued until the end of follow-up in nine patients or until death from recurrent disease in five. No complications of dilatation were seen.

Mitomycin-C: 'a ray of hope' in refractory corrosive esophageal strictures.

PubMed

Nagaich, N; Nijhawan, S; Katiyar, P; Sharma, R; Rathore, M

2014-04-01

Increasingly frequent dilation may become a self-defeating cycle in refractory stricture as recurrent trauma enhance, scar formation, and ultimately recurrence and potential worsening of the stricture. In 12 patients of caustic induced esophageal stricture, who failed to respond despite rigorous dilatation regimen for more than one year, a trial of topical mitomycin-C application to improve dilatation results was undertaken, considering the recently reported efficacy and safety of this agent. Mitomycin-C was applied for 2-3 minutes at the strictured esophageal segment after dilation with wire-guided Savary-Gilliard dilator. Patient was kept nil by mouth for 2-3 hours. After 4-6 sessions of mitomycin-C treatment, resolution of symptoms and significant improvement in dysphagia score and periodic dilatation index was seen in all 12 patients. Mitomycin-C topical application may be a useful strategy in refractory corrosive esophageal strictures and salvage patients from surgery. © 2013 Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.

Improved pupil dilation with medication-soaked pledget sponges.

PubMed

Weddle, Celeste; Thomas, Nikki; Dienemann, Jacqueline

2013-08-01

Use of multiple preoperative drops for pupil dilation has been shown to be inexact, to delay surgery, and to cause dissatisfaction among perioperative personnel. This article reports on an evidence-based, quality improvement project to locate and appraise research on improved effectiveness and efficiency of mydriasis (ie, pupillary dilation), and the subsequent implementation of a pledget-sponge procedure for pupil dilation at one ambulatory surgery center. Project leaders used an evidence-based practice model to assess the problem, research options for improvement, define goals, and implement a pilot project to test the new dilation technique. Outcomes from the pilot project showed a reduced number of delays caused by poor pupil dilation and a decrease in procedure turnover time. The project team solicited informal feedback from preoperative nurses, which reflected increased satisfaction in preparing patients for cataract procedures. After facility administrators and surgeons accepted the procedure change, it was adopted for preoperative use for all patients undergoing cataract surgery at the ambulatory surgery center. Copyright © 2013 AORN, Inc. Published by Elsevier Inc. All rights reserved.

Total plasma proANP increases with atrial dilatation in horses.

PubMed

Van Der Vekens, N; Hunter, I; Timm, A; Decloedt, A; De Clercq, D; Deprez, P; Goetze, J P; van Loon, G

2015-12-19

Equine atrial natriuretic peptide (ANP) plasma concentrations are correlated with left atrial size. However, species-specific assays are lacking and the results from human assays are poorly reproducible. A new methodology called processing independent analysis (PIA) that measures the total proANP product in plasma has proven to be successful in human medicine, but has never been used in horses. The aims were to establish an equine proANP reference interval by measurement of the total proANP product using PIA and to examine the proANP concentrations in horses with atrial dilatation. Sample stability was studied by comparison of storage at -80°C and -20°C. Plasma samples were obtained from 23 healthy horses, 12 horses with moderate or severe valvular regurgitation without atrial dilatation and 42 horses with valvular regurgitation and atrial dilatation. The proANP concentration was significantly (P<0.001) higher in horses with atrial dilatation (761.4 (442.1-1859.1) pmol/l) than in healthy horses (491.6 (429.5-765.9) pmol/l; P<0.001) or horses with cardiac disease but without atrial dilatation (544.4 (457.0-677.6) pmol/l). A cut-off value (573.8 pmol/l) for detection of atrial dilatation was calculated. Sample storage at -80°C did not differ from sample storage at -20°C. The measurement of total proANP in plasma detects atrial dilatation in horses and may be useful for clinical evaluation in equine medicine. British Veterinary Association.

Physical training improves flow-mediated dilation in patients with the polymetabolic syndrome.

PubMed

Lavrencic, A; Salobir, B G; Keber, I

2000-02-01

Endothelial dysfunction that can be detected as impaired flow-mediated dilation by ultrasonography is an early event in atherogenesis and has been demonstrated in healthy subjects with risk factors for atherosclerosis many years before the appearance of atheromatous plaques. We examined the influence of physical training on flow-mediated dilation in patients with the polymetabolic syndrome. Twenty-nine asymptomatic men aged 40 to 60 years with the polymetabolic syndrome were randomly divided between the control group and the training group, which trained 3 times a week for 12 weeks. On high-resolution ultrasound images, the diameter of the brachial artery was measured at rest, after reactive hyperemia (causing flow-mediated, endothelium-dependent dilation), and after sublingual glyceryltrinitrate (causing endothelium-independent vasodilation) in all subjects before and after the training period. The training program induced an increase of 18% in physical fitness. Flow-mediated dilation increased from 5.3+/-2.8% to 7.3+/-2.7% (P<0. 05). There was no change in body mass index, blood pressure, insulin resistance, lipids, and big endothelin-1 in either group. Flow-mediated dilation measured before training was negatively correlated with resting heart rate, waist-to-hip ratio, and insulin resistance. Resting heart rate emerged as the only independent determinant, which explained 22% of the variation in flow-mediated dilation. In conclusion, our findings suggest that a 3-month physical training program, which improved maximal exercise capacity, enhances flow-mediated dilation in patients with the polymetabolic syndrome.

Topical mitomycin-C application in recurrent esophageal strictures after surgical repair of esophageal atresia.

PubMed

Chapuy, Laurence; Pomerleau, Martine; Faure, Christophe

2014-11-01

The aim of the present study was to evaluate the efficacy and short-term safety of topical mitomycin-C, an antifibrotic agent, in preventing the recurrence of anastomotic strictures after surgical repair of esophageal atresia (EA). We retrospectively reviewed the medical records of patients with recurrent anastomotic strictures after EA surgery who underwent at least 3 esophageal dilations. We compared the outcome (ie, resolution of the stricture) of the group that received topical mitomycin-C treatment with endoscopic esophageal dilation with a historical cohort treated by dilations alone. A total of 11 children received mitomycin-C concurrently with endoscopic dilations. After a median follow-up of 33 months (range 18-72), and a mean number of 5.4 dilations per patient (range 3-11), 8 of 11 patients achieved a resolution of their strictures, 2 patients remained with stenosis, and 1 patient needed a surgical correction. In the control group, 10 patients required an average of 3.7 (range 3-7) total dilations. After a follow-up of 125 months (range 35-266) after the last dilation, strictures in 9 of 10 children disappeared and the remaining patient was symptom free. No dysplasia related to mitomycin-C was demonstrated. There is no benefit in the resolution of the stricture when adding mitomycin-C treatment compared with repeated esophageal dilations alone in historical controls. Further randomized controlled studies and a short- and long-term evaluation of safety are needed.

21 CFR 876.5450 - Rectal dilator.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Rectal dilator. 876.5450 Section 876.5450 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5450 Rectal dilator. (a) Identification. A rectal...

Pregnancy rates after ewes were treated with estradiol-17beta and oxytocin.

USDA-ARS?s Scientific Manuscript database

Cervical dilation may improve transcervical sheep embryo-transfer procedures, if the cervical dilation method does not reduce pregnancy rates. This experiment was conducted to determine whether estradiol-17beta-oxytocin treatment, which dilates the cervix in luteal-phase ewes, affects pregnancy rat...

21 CFR 876.5450 - Rectal dilator.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Rectal dilator. 876.5450 Section 876.5450 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5450 Rectal dilator. (a) Identification. A rectal...

Dilated Canine Hearts: A Specimen for Teaching Cardiac Anatomy

ERIC Educational Resources Information Center

Cope, Lee Anne

2008-01-01

Dilated canine hearts were used to teach undergraduate students internal and external cardiac anatomy. The specimens were dilated using hydrostatic pressure and then fixed using 5% formalin. These specimens provided the students with an alternative to prepackaged embalmed hearts and anatomical models for studying the external and internal cardiac…

Comparison of the Eder-Puestow and Celestin techniques for dilating benign oesophageal strictures.

PubMed

Hine, K R; Hawkey, C J; Atkinson, M; Holmes, G K

1984-10-01

The Celestin and Eder-Puestow methods of dilating benign oesophageal strictures have been compared prospectively in a randomised trial. One hundred and thirty three dilatations were performed on 72 patients. There was no significant difference between the two techniques with regard to the long term relief of symptoms. Celestin dilatation was quicker, less likely to cause pharyngeal trauma, and less damaging to guide wires. It could not be used, however, in those patients in whom only a short length of guide wire could be passed through the stricture.

Comparison of the Eder-Puestow and Celestin techniques for dilating benign oesophageal strictures.

PubMed Central

Hine, K R; Hawkey, C J; Atkinson, M; Holmes, G K

1984-01-01

The Celestin and Eder-Puestow methods of dilating benign oesophageal strictures have been compared prospectively in a randomised trial. One hundred and thirty three dilatations were performed on 72 patients. There was no significant difference between the two techniques with regard to the long term relief of symptoms. Celestin dilatation was quicker, less likely to cause pharyngeal trauma, and less damaging to guide wires. It could not be used, however, in those patients in whom only a short length of guide wire could be passed through the stricture. PMID:6479685

[Results of percutaneous transluminal dilatation of cerebral vascular stenoses].

PubMed

Kachel, R; Ritter, H; Grossmann, K; Glaser, F H

1986-03-01

The present paper is a review of 37 successful catheter dilatations of supra-aortic vascular stenoses. There were sixteen patients with a total of 21 stenoses of the internal carotid, vertebral artery or common carotid artery and sixteen patients with subclavian stenoses. Amongst the patients with stenoses of the cerebral vessels, there were ten with multiple lesions and six with a single stenosis. Three patients had successful dilatations of bilateral stenoses. The indications, technique, and complications of catheter dilatation of lesions of the cerebral vessels are described and discussed.

Pathologic aneurysmal dilation of the ascending aorta and dilation of the main pulmonary artery in patients with Kabuki syndrome: valve-sparing aortic root replacement.

PubMed

Dyamenahalli, Umesh; Abraham, Boban; Fontenot, Eudice; Prasad, Vinay; Imamura, Michiaki

2007-01-01

We report the aneurysmal dilation of the ascending aorta and the main pulmonary artery in 2 children with Kabuki syndrome. In 1 patient, there was progressive aneurysmal dilation of the ascending aorta necessitating aortoplasty. Histologic examination of the resected aorta revealed disrupted and fragmented elastic fibers in the medial layer, along with mucinous degeneration of the aortic wall. This is the first recognition and report of these findings as part of the Kabuki syndrome.

FATAL GASTRIC DILATION IN TWO ADULT BLACK-FOOTED FERRETS (MUSTELA NIGRIPES).

PubMed

Hinton, Jenna D; Aitken-Palmer, Copper; Joyner, Priscilla H; Ware, Lisa; Walsh, Timothy F

2016-03-01

Acute gastric dilation resulting in death was identified in two adult black-footed ferrets (Mustela nigripes) housed at the Smithsonian Conservation Biology Institute in Front Royal, Virginia. Both individuals were adult males (3 and 5 yr) and previously clinically healthy prior to the event. The etiology of gastric dilation in both cases could not be definitively determined, and necropsy revealed severe cardiovascular compromise secondary to bloat. Limited literature is available regarding a syndrome of this type in adult black-footed ferrets. Differential diagnoses considered included gastric dilatation volvulus (GDV), severe gastric distention of unknown origin, and gastric outflow obstruction. Given the severity of this syndrome and the findings in these two cases, acute gastric dilation should be considered in black-footed ferrets presenting with acute abdominal distention, respiratory distress, and cardiovascular compromise.

Mechanisms of hypoxia-induced cerebrovascular dilation in the newborn pig.

PubMed

Leffler, C W; Smith, J S; Edrington, J L; Zuckerman, S L; Parfenova, H

1997-03-01

The hypothesis that endothelium-dependent components contribute to the cerebromicrovascular dilation to hypoxia in the newborn pig was addressed. Piglets anesthetized with ketamine-acepromazine and maintained on alpha-chloralose were equipped with closed cranial windows. Injury to the endothelium of pial arterioles was produced by light activation of fluorescein dye. Light/dye injury reduced the pial arteriolar dilation to hypoxia (5 min, arterial PO2 approximately 30 mmHg) from 57 +/- 9 to 19 +/- 5%. Light/dye injury abolished the pial arteriolar dilation to hypercapnia but did not affect dilation to sodium nitroprusside. The pial arteriolar dilation to hypoxia was not affected by tetrodotoxin, N(omega)-nitro-L-arginine, glibenclamide, iberiotoxin, charybdotoxin, tetraethylammonium, or 8-phenyltheophylline. Hypoxia caused increases in the cerebral cortical production of adenosine 3',5'-cyclic monophosphate and guanosine 3',5'-cyclic monophosphate. Cerebral vasodilation to hypoxia was inhibited by 5,8,11,14-eicosatetraynoic acid but was not greatly affected by cyclooxygenase or lipoxygenase inhibitors. In contrast, the cytochrome P-450 epoxygenase inhibitor miconazol decreased cerebral vasodilation to hypoxia from 45 +/- 5 to 17 +/- 4%. Therefore, the vascular endothelium appears to participate in cerebral microvascular dilation to hypoxia in newborn pigs. The mechanism may include cytochrome P-450 epoxygenase metabolites of arachidonic acid.

Esophageal stenosis in epidermolysis bullosum: a challenge for the endoscopist.

PubMed

De Angelis, Paola; Caldaro, Tamara; Torroni, Filippo; Romeo, Erminia; Foschia, Francesca; di Abriola, Giovanni Federici; Rea, Francesca; El Hachem, May; Genovese, Elisabetta; D'Alessandro, Sandra; Dall'Oglio, Luigi

2011-05-01

Esophageal stenosis is a severe complication in dystrophic epidermolysis bullosa (EB). Endoscopic dilations may cause mucosal injury with stricture recurrence. Our aim was to describe our referral EB-center experience on safety and long-term efficacy of fluoroscopically guided balloon dilation without endoscopy. Over 14 years, 34 patients with EB, previously evaluated with barium esophagogram for dysphagia, underwent balloon esophageal dilation. Under fluoroscopy, a guide wire was introduced via a nostril into the stomach. A 12-mm pneumatic balloon, which passed over the wire, was filled using radio-opaque contrast, dilating the stricture. Orotracheal intubation was avoided. Antibiotics, dexamethasone, and proton-pump inhibitors were administered. Study approval was obtained from our ethical board. Ninety-three dilations were performed. Seventeen patients had a single stenosis. The mean age of onset was 18 years (range, 3-47 years). Thirteen patients underwent one dilation. In 6 cases, endoscopy was necessary to visualize the esophageal lumen. Complications included cervical esophageal perforation (2) and transitory dysphagia (10). Thirty patients were feeding within 24 hours. During the follow-up, 2 patients required a gastrostomy, and 2 patients underwent fundoplication for gastroesophageal reflux disease. Fluoroscopically guided balloon dilation in EB is a safe and well-tolerated procedure. An experienced endoscopy team is necessary in certain cases. Copyright © 2011 Elsevier Inc. All rights reserved.

Laser-driven short-duration heating angioplasty: dilatation performance in cadaver atherosclerotic femoral arteries

NASA Astrophysics Data System (ADS)

Shimazaki, Natsumi; Naruse, Sho; Arai, Tsunenori; Imanishi, Nobuaki; Aiso, Sadakazu

2013-03-01

The purpose of this study was to investigate the artery dilatation performance of the short-duration heating balloon catheter in cadaver stenotic arteries. We designed a prototype short-duration heating balloon catheter that can heat artery media to around 60 °C in 15-25 s by a combination of laser-driven heat generation and continuous fluid irrigation in the balloon. We performed ex vivo short-duration heating dilatation in the cadaver atherosclerotic femoral arteries (initial percent diameter stenosis was 36-98%), with the maximum balloon temperature of 65+/-5 °C, laser irradiation duration of 25 s, and balloon dilatation pressure of 3.5 atm. The artery lumen configurations before and after the dilatations were assessed with a commercial IVUS system. After the short-duration heating dilatations, the percent diameter stenosis was reduced below 30% without any artery tears or dissections. We estimated that the artery media temperature was raised to around 60 °C in which plaque thickness was below 0.8 mm by a thermal conduction calculation. The estimated maximum temperature in artery adventitia and surrounding tissue was up to 45 °C. We found that the short-duration heating balloon could sufficiently dilate the cadaver stenotic arteries, without thermal injury in artery adventitia and surroundings.

Effects of SP6 Acupuncture Point Stimulation on Labor Pain and Duration of Labor

PubMed Central

Yesilcicek Calik, Kiymet; Komurcu, Nuran

2014-01-01

Background: Acupressure has been used frequently to improve labor, manage labor pain, and shorten delivery time. However, there has been little research-based evidence to support the positive effects of acupressure in the obstetric area and obstetric nursing. Objectives: The aim of this study was to evaluate the effects of SP6 acupressure on labor pain and delivery time in primigravida women in labor. Patients and Methods: The study was conducted at the Trabzon Maternity Hospital in Turkey. Its design was a randomized controlled clinical trial study using a single-blinded method. One hundred (100) primigravida women in labor were randomly assigned to either the SP6 acupressure (n = 50) or control group (n = 50). Acupressure was practiced 35 times in total on the SP6 point of both legs in the SP6 acupressure group; 15 times (during contraction) when cervical dilation was 2-3 cm, 10 times when cervical dilation was 5-6 cm and 10 times at 9-10 cm dilation, while the women in the control group received standard care. Labor pain was measured five times using a structured questionnaire of a subjective labor pain scale (visual analogue scale-VAS) when dilation was 2-3 cm (VAS 2), 5-6 cm (VAS 3) and 8-9 cm (VAS 4) before and after acupressure was applied to the SP6 point (VAS 1), and finally at the early postpartum period (VAS 5). The duration of labor in both groups was measured with a partograph and the length of delivery time was calculated in two stages: from 3 cm cervical dilation to full cervical dilation, and from full cervical dilation to delivery. Results: There were significant differences between the groups in subjective labor pain scores (except VAS 4) (P < 0.001). The duration of the Phase one (3 cm dilatation to full dilatation) and Phase two (full dilatation to birth) in the acupressure group was shorter than the control group (Phase one, 225 min and 320 min, respectively; Phase two, 15 min and 20 min, respectively; both P < 0.001). Conclusions: It was determined that SP6 acupressure was effective in decreasing pain and duration of labor. PMID:25558386

Aortic valve dysfunction and aortic dilation in adults with coarctation of the aorta.

PubMed

Clair, Mathieu; Fernandes, Susan M; Khairy, Paul; Graham, Dionne A; Krieger, Eric V; Opotowsky, Alexander R; Singh, Michael N; Colan, Steven D; Meijboom, Erik J; Landzberg, Michael J

2014-01-01

To determine the prevalence of aortic valve dysfunction, aortic dilation, and aortic valve and ascending aortic intervention in adults with coarctation of the aorta (CoA). Aortic valve dysfunction and aortic dilation are rare among children and adolescents with CoA. With longer follow-up, adults may be more likely to have progressive disease. We retrospectively reviewed all adults with CoA, repaired or unrepaired, seen at our center between 2004 and 2010. Two hundred sixteen adults (56.0% male) with CoA were identified. Median age at last evaluation was 28.3 (range 18.0 to 75.3) years. Bicuspid aortic valve (BAV) was present in 65.7%. At last follow-up, 3.2% had moderate or severe aortic stenosis, and 3.7% had moderate or severe aortic regurgitation. Dilation of the aortic root or ascending aorta was present in 28.0% and 41.6% of patients, respectively. Moderate or severe aortic root or ascending aortic dilation (z-score > 4) was present in 8.2% and 13.7%, respectively. Patients with BAV were more likely to have moderate or severe ascending aortic dilation compared with those without BAV (19.5% vs. 0%; P < 0.001). Age was associated with ascending aortic dilation (P = 0.04). At most recent follow-up, 5.6% had undergone aortic valve intervention, and 3.2% had aortic root or ascending aortic replacement. In adults with CoA, significant aortic valve dysfunction and interventions during early adulthood were uncommon. However, aortic dilation was prevalent, especially of the ascending aorta, in patients with BAV. © 2013 Wiley Periodicals, Inc.

Pravastatin and endothelium dependent vasomotion after coronary angioplasty: the PREFACE trial.

PubMed

Mulder, H J; Schalij, M J; Kauer, B; Visser, R F; van Dijkman, P R; Jukema, J W; Zwinderman, A H; Bruschke, A V

2001-11-01

To test the hypothesis that the 3-hydroxy-3-methylglutaryl coenzyme-A reductase inhibitor pravastatin ameliorates endothelium mediated responses of dilated coronary segments: the PREFACE (pravastatin related effects following angioplasty on coronary endothelium) trial. A double blind, randomised, placebo controlled, multicentre study. Four hospitals in the Netherlands. 63 non-smoking, non-hypercholesterolaemic patients scheduled for elective balloon angioplasty (pravastatin 34, placebo 29). The effects of three months of pravastatin treatment (40 mg daily) on endothelium dependent vasomotor function were studied. Balloon angioplasty was undertaken one month after randomisation, and coronary vasomotor function tests using acetylcholine were performed two months after balloon angioplasty. The angiograms were analysed quantitatively. The efficacy measure was the acetylcholine induced change in mean arterial diameter, determined in the dilated segment and in an angiographically normal segment of an adjacent non-manipulated coronary artery. Increasing acetylcholine doses produced vasoconstriction in the dilated segments (p = 0.004) but not in the normal segments. Pravastatin did not affect the vascular response to acetylcholine in either the dilated segments (p = 0.09) or the non-dilated sites. Endothelium dependent vasomotion in normal segments was correlated with that in dilated segments (r = 0.47, p < 0.001). There were fewer procedure related events in the pravastatin group than in the placebo group (p < 0.05). Endothelium dependent vasomotion in normal segments is correlated with that in dilated segments. A significant beneficial effect of pravastatin on endothelial function could not be shown, but in the dilated segments there was a trend towards a beneficial treatment effect in the pravastatin group.

A randomized trial of vaginal misoprostol for cervical priming before hysteroscopy in postmenopausal women

PubMed Central

Kant, Anita; Divyakumar; Priyambada, Usha

2011-01-01

Objective: To perform hysteroscopy the cervix needs to be dilated and in nullipara and postmenopausal women this is sometimes difficult. Well-known, entry-related complications during hysteroscopy include cervical tear, creation of false tract, bleeding, uterine perforation, scarring, and subsequent anatomical stenosis. Materials and Methods: This study was done to investigate the priming effect of vaginal misoprostol on cervical dilatation in postmenopausal women, before hysteroscopy, to prevent such complications. Two hundred micrograms of misoprostol was inserted into the vagina at least 12 hours before the procedure and the control group did not receive any cervical priming agent. Pre-procedural dilatation, additional dilatation required, and time taken for dilatation was noted in each case. Observations: The study showed a significant difference between the study group (7.7 ± 1.7 mm) and the control group (4.5 ± 1.8 mm) in terms of pre-procedural cervical width and the number of women requiring a dditional dilatation (7 / 25 versus 22 / 25), and hence, the time required for dilatation (4.7 ± 8 seconds versus 20.6 ± 9.3 seconds). Conclusion: The pre-procedural cervical width was significantly more in the study group as compared to that in the control group. We found significant differences between the study and control groups with respect to the number of women who required cervical dilatation. To conclude, this study helps derive a conclusion that vaginal misoprostol as a cervical priming agent in postmenopausal women appears to be safe, effective, and inexpensive, with mild side effects. PMID:21897735

Exome Sequencing Establishes Diagnosis of Alström Syndrome in an Infant Presenting with Non-Syndromic Dilated Cardiomyopathy

PubMed Central

Long, Pamela A.; Evans, Jared M.; Olson, Timothy M.

2015-01-01

Idiopathic dilated cardiomyopathy is a heritable, genetically heterogeneous disorder characterized by progressive heart failure. Dilated cardiomyopathy typically exhibits autosomal dominant inheritance, yet frequently remains clinically silent until adulthood. We sought to discover the molecular basis of idiopathic, non-syndromic dilated cardiomyopathy in a one-month-old male presenting with severe heart failure. Previous comprehensive testing of blood, urine, and skin biopsy specimen was negative for metabolic, mitochondrial, storage, and infectious etiologies. Ophthalmologic examination was normal. Chromosomal microarray and commercial dilated cardiomyopathy gene panel testing failed to identify a causative mutation. Parental screening echocardiograms revealed no evidence of clinically silent dilated cardiomyopathy. Whole exome sequencing was carried out on the family trio on a research basis, filtering for rare, deleterious, recessive and de novo genetic variants. Pathogenic compound heterozygous truncating mutations were identified in ALMS1, diagnostic of Alström syndrome and prompting disclosure of genetic findings. Alström syndrome is a known cause for dilated cardiomyopathy in children yet delayed and mis-diagnosis are common owing to its rarity and age-dependent emergence of multisystem clinical manifestations. At six months of age the patient ultimately developed bilateral nystagmus and hyperopia, features characteristic of the syndrome. Early diagnosis is guiding clinical monitoring of other organ systems and allowing for presymptomatic intervention. Furthermore, recognition of recessive inheritance as the mechanism for sporadic disease has informed family planning. This case highlights a limitation of standard gene testing panels for pediatric dilated cardiomyopathy and exemplifies the potential for whole exome sequencing to solve a diagnostic dilemma and enable personalized care. PMID:25706677

Cricopharyngeal dilatation for the long-term treatment of dysphagia in oculopharyngeal muscular dystrophy.

PubMed

Manjaly, Joseph G; Vaughan-Shaw, Peter G; Dale, Oliver T; Tyler, Susan; Corlett, Jonathan C R; Frost, Roger A

2012-06-01

Oculopharyngeal muscular dystrophy (OPMD) is a rare autosomal dominant, progressive degenerative muscle disorder featuring dysphagia with limited therapeutic options. The aim of this study was to evaluate the safety and efficacy of repeated endoscopic dilatation for OPMD over a 15-year period. All patients seen at our Regional Swallowing Clinic with OPMD confirmed by genetic analysis were included. Cricopharyngeal dilatation was performed as an outpatient procedure using a wire-guided 18-mm (54 Fr) Savary-Gilliard bougie with the patient under sedation. Patients were offered repeat endoscopic dilatation when symptoms recurred. Symptom severity prior to initial dilatation and at follow-up was evaluated using the Sydney Swallow Questionnaire (SSQ). Nine patients (7 female, 2 male) were included for analysis. Median total treatment period was 13 years (range = 3-15), median number of dilatations per patient was 7.2 (range = 1-16), and median interval between treatments was 15 months (range = 4.5-45). All patients recorded sustained symptom improvement. Mean SSQ score (out of 1,700) was 1,108.11 (SD ± 272.85) prior to first dilatation and 297.78 (SD ± 189.14) at last follow-up, representing a 73% decrease (95% CI = 52-94) in degree of dysphagia symptoms (paired t-test, P = 0.0001). All mean scores for individual questions also showed significant improvement (P < 0.05). No adverse events were reported with all patients maintaining oral feeding at last follow-up. Repeated cricopharyngeal dilatation is a safe, effective, well-tolerated, and long-lasting treatment for dysphagia in OPMD.

Laparoscopic Heller myotomy and fundoplication in patients with Chagas' disease achalasia and massively dilated esophagus.

PubMed

Pantanali, Carlos A R; Herbella, Fernando A M; Henry, Maria A; Mattos Farah, Jose Francisco; Patti, Marco G

2013-01-01

Laparoscopic Heller myotomy and fundoplication is considered today the treatment of choice for achalasia. The optimal treatment for end-stage achalasia with esophageal dilation is still controversial. This multicenter and retrospective study aims to evaluate the outcome of laparoscopic Heller myotomy in patients with a massively dilated esophagus. Eleven patients (mean age, 56 years; 6 men) with massively dilated esophagus (esophageal diameter greater than 10 cm) underwent a laparoscopic Heller myotomy and anterior fundoplication between 2000 and 2009 at three different institutions. Preoperative workup included upper endoscopy, esophagram, and esophageal manometry in all patients. Average follow-up was 31.5 months (range, 3 to 60 months). Two patients (18%) had severe dysphagia, four patients (36%) had mild and occasional dysphagia to solid food, and five patients (45%) were asymptomatic. All patients gained or kept body weight, except for the two patients with severe dysphagia. Of the two patients with severe dysphagia, one underwent esophageal dilatation and the other a laparoscopic esophagectomy. They are both doing well. Heller myotomy relieves dysphagia in the majority of patients even when the esophagus is massively dilated.

Canine candidate genes for dilated cardiomyopathy: annotation of and polymorphic markers for 14 genes

PubMed Central

Wiersma, Anje C; Leegwater, Peter AJ; van Oost, Bernard A; Ollier, William E; Dukes-McEwan, Joanna

2007-01-01

Background Dilated cardiomyopathy is a myocardial disease occurring in humans and domestic animals and is characterized by dilatation of the left ventricle, reduced systolic function and increased sphericity of the left ventricle. Dilated cardiomyopathy has been observed in several, mostly large and giant, dog breeds, such as the Dobermann and the Great Dane. A number of genes have been identified, which are associated with dilated cardiomyopathy in the human, mouse and hamster. These genes mainly encode structural proteins of the cardiac myocyte. Results We present the annotation of, and marker development for, 14 of these genes of the dog genome, i.e. α-cardiac actin, caveolin 1, cysteine-rich protein 3, desmin, lamin A/C, LIM-domain binding factor 3, myosin heavy polypeptide 7, phospholamban, sarcoglycan δ, titin cap, α-tropomyosin, troponin I, troponin T and vinculin. A total of 33 Single Nucleotide Polymorphisms were identified for these canine genes and 11 polymorphic microsatellite repeats were developed. Conclusion The presented polymorphisms provide a tool to investigate the role of the corresponding genes in canine Dilated Cardiomyopathy by linkage analysis or association studies. PMID:17949487

Canine candidate genes for dilated cardiomyopathy: annotation of and polymorphic markers for 14 genes.

PubMed

Wiersma, Anje C; Leegwater, Peter Aj; van Oost, Bernard A; Ollier, William E; Dukes-McEwan, Joanna

2007-10-19

Dilated cardiomyopathy is a myocardial disease occurring in humans and domestic animals and is characterized by dilatation of the left ventricle, reduced systolic function and increased sphericity of the left ventricle. Dilated cardiomyopathy has been observed in several, mostly large and giant, dog breeds, such as the Dobermann and the Great Dane. A number of genes have been identified, which are associated with dilated cardiomyopathy in the human, mouse and hamster. These genes mainly encode structural proteins of the cardiac myocyte. We present the annotation of, and marker development for, 14 of these genes of the dog genome, i.e. alpha-cardiac actin, caveolin 1, cysteine-rich protein 3, desmin, lamin A/C, LIM-domain binding factor 3, myosin heavy polypeptide 7, phospholamban, sarcoglycan delta, titin cap, alpha-tropomyosin, troponin I, troponin T and vinculin. A total of 33 Single Nucleotide Polymorphisms were identified for these canine genes and 11 polymorphic microsatellite repeats were developed. The presented polymorphisms provide a tool to investigate the role of the corresponding genes in canine Dilated Cardiomyopathy by linkage analysis or association studies.

Stress-Dilatancy of Cambria Sand for Triaxial Tests at High Pressures

NASA Astrophysics Data System (ADS)

Szypcio, Zenon

2017-12-01

In this paper, the stress-dilatancy relationship of Cambria sand for drained triaxial compression and extension tests at high stress level is investigated. The stress dilatancy relationship is obtained by use of frictional state theory and experimental tests data published in literature. It is shown that stress-dilatancy relationship is bilinear, described by three parameters of frictional state theory: critical frictional angle and two other parameters. It is accepted that critical friction angle is independent of confining pressure. The two additional parameters are strongly dependent on confining pressure and different for initial and advanced stages. The point at which the values of these parameters change is termed as Transformation Shear Point. This point is not simply visible either in stress ratio-strain or the volume strain-shear strain relationship which are traditionally shown in soil mechanics papers. Transformation Shear Point is very characteristic in stress ratio-plastic dilatancy plane. Thus, stress ratio- plastic dilatancy is very important for describing stress-strain behaviour of soils. The relationship shown in the paper can be used in soil modelling in the future.

Risk factors associated with refractoriness to esophageal dilatation for benign dysphagia.

PubMed

Rodrigues-Pinto, Eduardo; Pereira, Pedro; Ribeiro, Armando; Lopes, Susana; Moutinho-Ribeiro, Pedro; Silva, Marco; Peixoto, Armando; Gaspar, Rui; Macedo, Guilherme

2016-06-01

Benign esophageal strictures need repeated dilatations to relieve dysphagia. Literature is scarce on the risk factors for refractoriness of these strictures. This study aimed to assess the risk factors associated with refractory strictures. This is a retrospective study of patients with benign esophageal strictures who were referred for esophageal dilatation over a period of 3 years. A total of 327 esophageal dilatations were performed in 103 patients; 53% of the patients reported dysphagia for liquids. Clinical success was achieved in 77% of the patients. There was a need for further dilatations in 54% of patients, being more frequent in patients with dysphagia for liquids [78 vs. 64%, P=0.008, odds ratio (OR) 1.930], in those with caustic strictures (89 vs. 70%, P=0.007, OR 3.487), and in those with complex strictures (83 vs. 70%, P=0.047, OR 2.132). Caustic strictures, peptic strictures, and complex strictures showed statistical significance in the multivariate analysis. Time until subsequent dilatations was less in patients with dysphagia for liquids (49 vs. 182 days, P<0.001), in those with peptic strictures (49 vs. 98 days, P=0.004), in those with caustic strictures (49 vs. 78 days, P=0.005), and in patients with complex strictures (47 vs. 80 days P=0.009). In multivariate analysis, further dilatations occurred earlier in patients with dysphagia for liquids [hazard ratio (HR) 1.506, P=0.004], in those with peptic strictures (HR 1.644, P=0.002), in those with caustic strictures (HR 1.581, P=0.016), and in patients with complex strictures (HR 1.408, P=0.046). Caustic, peptic, and complex strictures were associated with a greater need for subsequent dilatations. Time until subsequent dilatations was less in patients with dysphagia for liquids and in those with caustic, peptic, and complex strictures.

Serial Versus Direct Dilation of Small Diameter Stents Results in a More Predictable and Complete Intentional Transcatheter Stent Fracture: A PICES Bench Testing Study.

PubMed

Crystal, Matthew A; Morgan, Gareth J; Danon, Saar; Gray, Robert G; Gruenstein, Daniel H; Gordon, Brent M; Goldstein, Bryan H

2018-01-01

Balloon-expandable stents, implanted in infants and children with congenital heart disease (CHD), often require redilation to match somatic growth. Small diameter stents may eventually require longitudinal surgical transection to prevent iatrogenic vascular stenosis. Intentional transcatheter stent fracture (TSF) is an emerging alternative approach to stent transection, but little is known about the optimal stent substrate and best protocol to improve the likelihood of successful TSF. Bench testing was performed with a stent dilation protocol. After recording baseline characteristics, stents were serially or directly dilated using ultra-high-pressure balloons (UHPB) until fracture occurred or further stent dilation was not possible. Stent characteristics recorded were as follows: cell design, metallurgy, mechanism, and uniformity of fracture. Stents tested included bare-metal coronary stents, premounted small diameter stents, and ePTFE-covered small diameter premounted stents. Ninety-four stents representing 9 distinct models were maximally dilated, with 80 (85%) demonstrating evidence of fracture. Comprehensive fracture details were recorded in 64 stents: linear and complete in 34/64 stents (53.1%), linear and incomplete in 9/64 stents (14.1%), transverse/complex and complete in 6/64 stents (9.4%), and transverse/complex and incomplete in 15/64 stents (23.4%). Stent fracture was not accomplished in some stent models secondary to significant shortening, i.e., "napkin-ring" formation. Serial dilation resulted in evidence of fracture in 62/67 (92.5%) stents compared with 18/27 (66.7%) stents in the direct dilation group (p = 0.003). Intentional TSF is feasible in an ex vivo model. Serial dilation more reliably expanded the stent and allowed for ultimate stent fracture, whereas direct large diameter dilation of stents was more likely to generate a "napkin-ring" configuration, which may be more resistant to fracture. In vivo animal and human testing is necessary to better understand the response to attempted TSF for newly developed stents as well as those currently in use.

Prognostic Value of Ultrasound Grading Systems in Prenatally Diagnosed Unilateral Urinary Tract Dilatation.

PubMed

Scalabre, Aurélien; Demède, Delphine; Gaillard, Ségolène; Pracros, Jean-Pierre; Mouriquand, Pierre; Mure, Pierre-Yves

2017-04-01

We compared the prognostic value of anteroposterior intrasinus diameter of the renal pelvis, urinary tract dilatation and the Society for Fetal Urology grading system in children with prenatally diagnosed unilateral urinary tract dilatation. All newborns with prenatally diagnosed unilateral urinary tract dilatation, normal bladder and anteroposterior intrasinus diameter 10 mm or greater on the first postnatal ultrasonography were prospectively enrolled from January 2011 to February 2015. Indications for surgery were recurrent febrile urinary tract infections and/or decrease of relative renal function more than 10% on serial isotope studies and/or increasing anteroposterior intrasinus diameter greater than 20% on serial ultrasounds. Sensitivity, specificity and ROC curves were calculated to evaluate the accuracy of anteroposterior intrasinus diameter, urinary tract dilatation and Society for Fetal Urology grading system in determining which children would need surgery within 24 months. A total of 57 males and 13 females were included. Of the patients 33 required surgery at a median age of 5 months (IQR 3.8 to 6.4). Urinary tract dilatation remained stable in 14 cases and decreased in 23 with a median followup of 42 months (IQR 25 to 67). Anteroposterior intrasinus diameter, urinary tract dilatation and Society for Fetal Urology scores were all correlated with the need for surgery. Anteroposterior intrasinus diameter with a threshold of 20 mm had the best prognostic value, with a sensitivity of 81.8% and a specificity of 91.7%. Our study confirms that the prognostic value was comparable between anteroposterior intrasinus diameter of the renal pelvis, urinary tract dilatation and Society for Fetal Urology grading system in newborns with prenatally diagnosed unilateral urinary tract dilatation. Anteroposterior intrasinus diameter and abnormal parenchymal thickness are the most important ultrasound criteria to identify children at risk for requiring surgery. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

'X-ray'-free balloon dilation for totally ultrasound-guided percutaneous nephrolithotomy.

PubMed

Zhou, Tie; Chen, Guanghua; Gao, Xiaofeng; Zhang, Wei; Xu, Chuanliang; Li, Lei; Sun, Yinghao

2015-04-01

The objective of the study was to evaluate the feasibility and safety of balloon dilation for 'X-ray'-free ultrasound-guided percutaneous nephrolithotomy (PCNL). From January 2012 to December 2012, patients underwent 'X-ray'-free ultrasound-guided PCNL with Amplatz dilator (Group A). From January 2013 to April 2014, patients underwent 'X-ray'-free ultrasound-guided PCNL with balloon dilator (Group B). For balloon dilation, a 10 F fascial dilator was used to dilate the tract. Subsequently, the 6 F nephrostomy balloon (8 mm in diameter) was indwelled along the guidewire with a marked length equal to the dilation depth. Under the monitoring of ultrasound, the location of balloon was secured and disappearance of balloon waist was confirmed when the balloon was inflated at a pressure of 20 atm. A total of 163 patients were involved in this study. Of 81 procedures in Group A, 45 procedures were performed by a senior urologist while 36 procedures by a resident. Of 82 patients in Group B, 47 procedures were performed by the same senior urologist while 35 procedures by another resident. For the senior urologist, there was no statistically significant difference between two groups in calyx of entry, stone-free rate, decline of hemoglobin and hematocrit, operation time and hospitalization. But for the residents, there was less decline of hemoglobin and hematocrit, tract development time and hospitalization in Group B compared to Group A (0.6 vs. 1.7 g/dl, p = 0.001; 2.3% vs. 5.5%, p = 0.003; 10.1 vs. 11.0 min, p = 0.027; 7.8 vs. 13.9 days, p < 0.001). Balloon dilation method introduced in this study is compensable for tract development when 'X-ray'-free ultrasound-guided PCNL is performed. Modified techniques make totally ultrasound guidance for PCNL feasible, easy and safe. In addition, such a procedure is preferable for initial operators because of less hemorrhage complication.

[Successful endoscopic dilatation of a stenosis in relation to an ileorectal anastomosis by acute ileus].

PubMed

Kjærgaard, Jane Christensen; Hendel, Jakob; Gügenur, Ismail

2014-02-17

Endoscopic dilatation is a treatment option for patients with Crohns disease suffering from stenosis in relation to an ileorectal anastomosis. We present a case of a patient with Crohns disease who was admitted with acute obstructive symptoms due to a stensosis of the ileorectal anastomosis. The patient was septic. We performed a successful endoscopic dilatation in the acute phase and the patient was discharged few days after an uneventful recovery. Endoscopic dilatation of an ileorectal anastomsis in patients with Crohns disease is a treatment option in the acute setting when performed by experienced endoscopists.

Laws of physics help explain capillary non-perfusion in diabetic retinopathy.

PubMed

Stefánsson, E; Chan, Y K; Bek, T; Hardarson, S H; Wong, D; Wilson, D I

2018-02-01

The purpose is to use laws of physics to elucidate the mechanisms behind capillary non-perfusion in diabetic retinopathy. In diabetic retinopathy, loss of pericytes weakens capillary walls and the vessel dilates. A dilated capillary has reduced resistance to flow, therefore increased flow in that vessel and decreased in adjoining capillaries. A preferential shunt vessel is thus formed from the dilated capillary and the adjacent capillaries become non-perfused. We apply the laws of Laplace and Hagen-Poiseuille to better understand the phenomena that lead to capillary non-perfusion. These laws of physics can give a foundation for physical or mathematical models to further elucidate this field of study. The law of Laplace predicts that a weaker vessel wall will dilate, assuming constant transmural pressure. The Hagen-Poiseuille equation for flow and the Ostwald-de Waele relationship for viscosity predict that a dilated vessel will receive a higher portion of the fluid flow than the adjoining capillaries. Viscosity will decrease in the dilated vessel, furthering the imbalance and resulting in a patch of non-perfused capillaries next to the dilated 'preferential' shunt vessel. Physical principles support or inspire novel hypotheses to explain poorly understood phenomena in ophthalmology. This thesis of pericyte death and capillary remodelling, which was first proposed by Cogan and Kuwabara, already agrees with histological and angiographical observations in diabetic retinopathy. We have shown that it is also supported by classical laws of physics.

Ultrasonographic and clinicopathologic features of segmental dilatations of the common bile duct in four cats

PubMed Central

Spain, Heather N; Penninck, Dominique G; Webster, Cynthia RL; Daure, Evence; Jennings, Samuel H

2017-01-01

Case series summary This case series documents ultrasonographic and clinicopathologic features of four cats with marked segmental dilatations of the common bile duct (CBD). All cats had additional ultrasonographic changes to the hepatobiliary system, including hepatomegaly, tubular to saccular intra/extrahepatic biliary duct dilatation and biliary debris accumulation. Based on all available data the presence of extrahepatic biliary duct obstruction (EHBDO) was ruled out in 3/4 cases and was equivocal in one case. One cat underwent re-routing surgery to address the CBD dilatation after multiple recurrent infections, one cat was euthanized and had a post-mortem examination and two cats were medically managed with antibiotics, liver protectants, gastroprotectants and cholerectics. Relevance and novel information The ultrasonographic features of the CBD in this population of cats were supportive of choledochal cysts (CCs). The maximal diameter of the CBD dilatations exceeded 5 mm in all cases, a sign that has been previously reported to be consistent with EHBDO. In our study, dilatations were segmental rather than diffuse. Given the high morbidity and mortality associated with hepatobiliary surgery in cats, segmental dilatation of the CBD should not prompt emergency surgery. Some cats may respond to medical management. Careful planning for cyst resection was beneficial in one cat. Evaluation of CC morphology (eg, size, location, concurrent intrahepatic anomalies) may assist in selecting cats that could benefit from surgical intervention. PMID:28680700

One shot tract dilation for percutaneous nephrolithotomy: is it safe and effective in preschool children?

PubMed

Hosseini, Seyed Reza; Mohseni, Mohammad Ghasem; Alizadeh, Farshid

2014-01-01

To evaluate the safety and feasibility of percutaneous tract dilation by the one-stage method in preschool children. Between April 2009 and February 2013, all preschool (<6 years) children who were candidates for percutaneous nephrolithotomy were enrolled in this prospective study. Patients were randomly assigned to dilation by serial metallic dilators (group I, 31 patients) or dilation by one-stage Amplatz according to Frattini et al. [J Endourol 2001;15:919-923] (group II, 31 patients). The primary endpoint of interest was fluoroscopy time. Secondary endpoints included tract creation and dilation time, success rate and complications. Stone-free status was defined as residuals ≤3 mm. Age, stone size, operation success and operation time were not significantly different between the studied groups. The most common stone composition was calcium oxalate in both groups. The mean ± standard deviation of access and fluoroscopy times in groups I and II were 7.3 ± 1.2 min vs. 5.9 ± 1.5 min (p > 0.05) and 70.0 ± 8.9 s vs. 22.0 ± 5.6 s (p < 0.001), respectively. Postoperative complications included one case of postoperative fever lasting less than 48 h in group I. Percutaneous tract dilation by the one-stage method is safe and effective. Also, it is associated with considerably less radiation exposure in preschool children. © 2014 S. Karger AG, Basel.

Morphological Alterations Within the Peripheral Fixation of the Iris Dilator Muscle in Eyes With Pigmentary Glaucoma

PubMed Central

Flügel-Koch, Cassandra M.; Tektas, Ozan Y.; Kaufman, Paul L.; Paulsen, Friedrich P.; Lütjen-Drecoll, Elke

2014-01-01

Purpose. To analyze the peripheral fixation of the iris dilator muscle in normal eyes and in eyes with pigmentary glaucoma (PG). Methods. Using 63 control eyes (age 18 months–99 years), the peripheral iris dilator was investigated by light microscopy, immunohistochemistry, and electron microscopy. Development was studied using 18 differently aged fetal eyes stained immunohistochemically against α-smooth muscle (SM) actin. The peripheral iris dilator muscle in PG was analyzed using semithin and ultrathin sections of six glutaraldehyde-fixed eyes from three donors aged 38, 62, and 74 years. Results. In normal eyes, the peripheral end of the iris dilator muscle is arranged in a sphincter-like manner. Arcade-shaped tendinous connections associated with myofibroblasts (iridial strands) anchor the iris dilator within the elastic–fibromuscular ciliary meshwork that also serves as fixation area for the elastic tendons of the inner ciliary muscle portions. The iridial strands are innervated and can adapt their length during accommodation. The PG eyes show incomplete circular bundles and iridial strands that are mainly anchored to the iris stroma and the flexible uveal parts of the trabecular meshwork. Conclusions. The normal anchorage of the peripheral iris dilator and its presumably neuronally regulated length adaptation stabilize the peripheral iris during accommodation. Insufficient fixation in PG could promote posterior bowing of the iris with rubbing against the zonular fibers and pigment liberation from the iris pigmented epithelium. PMID:24938519

Endoscopy-guided balloon dilation of benign anastomotic strictures after radical gastrectomy for gastric cancer.

PubMed

Lee, Hyun Jik; Park, Wan; Lee, Hyuk; Lee, Keun Ho; Park, Jun Chul; Shin, Sung Kwan; Lee, Sang Kil; Lee, Yong Chan; Noh, Sung Hoon

2014-07-01

The aim of this study was to evaluate the outcome of endoscopic dilation for benign anastomotic stricture after radical gastrectomy in gastric cancer patients. Gastric cancer patients who underwent endoscopic balloon dilation for benign anastomosis stricture after radical gastrectomy during a 6-year period were reviewed retrospectively. Twenty-one patients developed benign strictures at the site of anastomosis. The majority of strictures occurred within 1 year after surgery (95.2%). The median duration to stenosis after surgery was 1.70 months (range, 0.17 to 23.97 months). The success rate of the first endoscopic dilation was 61.9%. Between the restenosis group (n=8) and the no restenosis group (n=13), there were no significant differences in the body mass index (22.82 kg/m(2) vs 22.46 kg/m(2)), interval to symptom onset (73.9 days vs 109.3 days), interval to treatment (84.6 days vs 115.6 days), maximal balloon diameter (14.12 mm vs 15.62 mm), number of balloon dilation sessions (1.75 vs 1.31), location of gastric cancer or type of surgery. One patient required surgery because of stricture refractory to repeated dilation. Endoscopic dilation is a highly effective treatment for benign anastomotic strictures after radical gastrectomy for gastric cancer and should be considered a primary intervention prior to proceeding with surgical revision.

Post-earthquake dilatancy recovery

NASA Technical Reports Server (NTRS)

Scholz, C. H.

1974-01-01

Geodetic measurements of the 1964 Niigata, Japan earthquake and of three other examples are briefly examined. They show exponentially decaying subsidence for a year after the quakes. The observations confirm the dilatancy-fluid diffusion model of earthquake precursors and clarify the extent and properties of the dilatant zone. An analysis using one-dimensional consolidation theory is included which agrees well with this interpretation.

Pravastatin and endothelium dependent vasomotion after coronary angioplasty: the PREFACE trial

PubMed Central

Mulder, H; Schalij, M; Kauer, B; Visser, R; van Dijkman, P R M; Jukema, J; Zwinderman, A; Bruschke, A

2001-01-01

OBJECTIVE—To test the hypothesis that the 3-hydroxy-3-methylglutaryl coenzyme-A reductase inhibitor pravastatin ameliorates endothelium mediated responses of dilated coronary segments: the PREFACE (pravastatin related effects following angioplasty on coronary endothelium) trial.
DESIGN—A double blind, randomised, placebo controlled, multicentre study.
SETTING—Four hospitals in the Netherlands.
PATIENTS—63 non-smoking, non-hypercholesterolaemic patients scheduled for elective balloon angioplasty (pravastatin 34, placebo 29).
INTERVENTIONS—The effects of three months of pravastatin treatment (40 mg daily) on endothelium dependent vasomotor function were studied. Balloon angioplasty was undertaken one month after randomisation, and coronary vasomotor function tests using acetylcholine were performed two months after balloon angioplasty. The angiograms were analysed quantitatively.
MAIN OUTCOME MEASURES—The efficacy measure was the acetylcholine induced change in mean arterial diameter, determined in the dilated segment and in an angiographically normal segment of an adjacent non-manipulated coronary artery.
RESULTS—Increasing acetylcholine doses produced vasoconstriction in the dilated segments (p = 0.004) but not in the normal segments. Pravastatin did not affect the vascular response to acetylcholine in either the dilated segments (p = 0.09) or the non-dilated sites. Endothelium dependent vasomotion in normal segments was correlated with that in dilated segments (r = 0.47, p < 0.001). There were fewer procedure related events in the pravastatin group than in the placebo group (p < 0.05).
CONCLUSIONS—Endothelium dependent vasomotion in normal segments is correlated with that in dilated segments. A significant beneficial effect of pravastatin on endothelial function could not be shown, but in the dilated segments there was a trend towards a beneficial treatment effect in the pravastatin group.


Keywords: angioplasty; endothelium; acetylcholine; pravastatin PMID:11602546

Tetralogy of Fallot and aortic root dilation: a long-term outlook.

PubMed

Nagy, Christian D; Alejo, Diane E; Corretti, Mary C; Ravekes, William J; Crosson, Jane E; Spevak, Philip J; Ringel, Richard; Carson, Kathryn A; Khalil, Sara; Dietz, Harry C; Cameron, Duke E; Vricella, Luca A; Traill, Thomas A; Holmes, Kathryn W

2013-04-01

Dilation of the sinus of Valsalva (SoV) has been increasingly observed after repaired tetralogy of Fallot (TOF). We estimate the prevalence of SoV dilation in adults with repaired TOF and analyze possible factors related to aortic disease. Adults with TOF [n = 109, median age 33.2 years (range 18.1 to 69.5)] evaluated at Johns Hopkins Hospital from 2001 to 2009 were reviewed in an observational retrospective cohort study. Median follow-up was 27.3 (range 0.1-48.8) years. SoV dilation was defined as >95 % confidence interval adjusted for age and body surface area (z-score > 2). The prevalence of SoV dilation was 51 % compared with that of a normal population with a mean z-score of 2.03. Maximal aortic diameters were ≥ 4 cm in 39 % (42 of 109), ≥ 4.5 cm in 21 % (23 of 109), ≥ 5 cm in 8 % (9 of 109), and ≥ 5.5 cm in 2 % (2 of 109). There was no aortic dissection or death due contributable to aortic disease. Aortic valve replacement was performed in 1.8 % and aortic root or ascending aorta (AA) replacement surgery in 2.8 % of patients. By multivariate logistic regression analysis, aortic regurgitation (AR) [odds ratio (OR) = 3.09, p = 0.005], residual ventricular septal defect (VSD) (OR = 4.14, p < 0.02), and TOF with pulmonary atresia (TOF/PA) (OR = 6.75, p = 0.03) were associated with increased odds of dilated aortic root. SoV dilation after TOF repair is common and persists with aging. AR, residual VSD, and TOF/PA are associated with increased odds of dilation. AA evaluation beyond the SoV is important. Indexed values are imperative to avoid bias on the basis of age and body surface area.

Aortic dilatation in patients with Turner's syndrome without structural cardiac anomaly.

PubMed

Alami Laroussi, Nassiba; Dahdah, Nagib; Dallaire, Frédéric; Thérien, Johanne; Fournier, Anne

2016-03-01

Dilatation of the ascending aorta is described in Turner's syndrome with variable prevalence (6.8-32%). Reported series typically include patients with associated cardiac anomalies. To characterise the prevalence, age of onset, and the progress of dilatation of the ascending aorta in Turner's syndrome patients free of structural cardiac anomalies. Potential risk factors such as karyotype and growth hormone therapy were analysed for correlation with aortic dilatation. We carried out a retrospective study with data collected from medical records and echocardiography studies. Patients with Tuner's syndrome followed-up between 1992 and 2010 with at least two echocardiography studies were eligible. Patients with previous cardiac surgery or under anti-hypertensive medication were excluded. Ascending aorta diameter measurements were adjusted for body surface area, and dilatation was defined as Z-score>2. The study population consisted of 44 patients, aged 11.9±7.4 years at the first echocardiogram and 17.9±7.3 years at the last follow-up, with a follow-up duration of 6.0±3.7 years. A total of 13 (29.5%) patients exhibited aortic dilatation during follow-up, suggesting an actuarial estimate of the freedom from aortic dilatation dropping from 86 to 70% and then to 37% at 10, 20, and 30 years of age, respectively. There was no statistically significant impact of karyotype or growth hormone therapy on aortic Z-score progression. The prevalence of dilatation of the ascending aorta in Turner's syndrome patients free of structural aortic anomalies is comparable with published data with associated lesions. Growth hormone therapy and karyotype had no significant impact; however, longitudinal follow-up is warranted.

Replacement of Dislodged Gastrostomy Tubes After Stoma Dilation in the Pediatric Emergency Department.

PubMed

Bhambani, Shiloni; Phan, Tammy H; Brown, Lance; Thorp, Andrea W

2017-06-01

A dislodged gastrostomy tube (GT) is a common complaint that requires evaluation in the pediatric emergency department (ED) and, on occasion, will require stoma dilation to successfully replace the GT. The objective of this study was to describe the frequency that stoma dilation is required, the success rate of replacement, complications encountered, and the techniques used to confirm placement of the GT after dilation. We conducted a retrospective medical record review of children 0-18 years who presented to the pediatric ED from February 2013 through February 2015 with a dislodged GT that required stoma dilation by pediatric emergency physicians with serially increasing Foley catheter sizes prior to successful placement of the GT. We reviewed a total of 302 encounters in 215 patients, with 97 (32%) of the encounters requiring stoma dilation prior to replacing a GT. The median amount of dilation was 2 French between the initial Foley catheter size and the final GT size. There was a single complication of a mal-positioned balloon that was identified at the index visit. No delayed complications were encountered. We performed confirmation of placement in all patients. The two most common forms of confirmation were aspiration of gastric contents (56/97 [58%]) followed by contrast radiograph in 39 (40%). The practice of serial dilation of a gastrostomy stoma site to allow successful replacement of a gastrostomy tube in pediatric patients who present to the ED with a dislodged gastrostomy tube is generally successful and without increased complication. All patients received at least one form of confirmation for appropriate GT placement with the most common being aspiration of gastric contents.

Echocardiographic assessment of the aortic root dilatation in adult patients after tetralogy of Fallot repair.

PubMed

Cruz, Cristina; Pinho, Teresa; Lebreiro, Ana; Silva Cardoso, José; Maciel, Maria Júlia

2013-06-01

Transthoracic echocardiography is an important tool after tetralogy of Fallot repair, of which aortic root dilatation is a recognized complication. In this study we aimed to assess its prevalence and potential predictors. We consecutively assessed adult patients by transthoracic echocardiography after tetralogy of Fallot repair, and divided them into two groups based on the maximum internal aortic diameter at the sinuses of Valsalva in parasternal long-axis view: group 1 with aortic root dilatation (≥38 mm) and group 2 without dilatation (<38 mm). A total of 53 patients were included, mean age 32±10 years, with a mean time since surgery of 23±7 years. An aortopulmonary shunt had been performed prior to complete repair in 25 patients, and a transannular patch was used in 19 patients. Aortic root measurement was possible in all patients. Aortic root dilatation was identified in eight patients (15%), all male. Male gender (p=0.001), body surface area (1.93±0.10 vs. 1.70±0.20 m(2), p=0.03) and increased left ventricular end-diastolic diameter (p=0.005) were predictors of aortic root dilatation. None of the surgical variables studied were predictors of aortic root dilatation. The prevalence of aortic root dilatation in this cohort was low and male gender was a predictor of its occurrence. The type of repair and time to surgery did not influence its occurrence. Quantification of aortic root diameter is possible by transthoracic echocardiography; we suggest indexing it to body surface area in clinical practice. Copyright © 2012 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

No Beneficial Effect of General and Specific Anti-Inflammatory Therapies on Aortic Dilatation in Marfan Mice

PubMed Central

den Hartog, Alexander W.; Radonic, Teodora; de Vries, Carlie J. M.; Zwinderman, Aeilko H.; Groenink, Maarten; Mulder, Barbara J. M.; de Waard, Vivian

2014-01-01

Aims Patients with Marfan syndrome have an increased risk of life-threatening aortic complications, mostly preceded by aortic dilatation. In the FBN1 C1039G/+ Marfan mouse model, losartan decreases aortic root dilatation. We recently confirmed this beneficial effect of losartan in adult patients with Marfan syndrome. The straightforward translation of this mouse model to man is reassuring to test novel treatment strategies. A number of studies have shown signs of inflammation in aortic tissue of Marfan patients. This study examined the efficacy of anti-inflammatory therapies in attenuating aortic root dilation in Marfan syndrome and compared effects to the main preventative agent, losartan. Methods and Results To inhibit inflammation in FBN1 C1039G/+ Marfan mice, we treated the mice with losartan (angiotensin II receptor type 1 inhibitor), methylprednisolone (corticosteroid) or abatacept (T-cell-specific inhibitor). Treatment was initiated in adult Marfan mice with already existing aortic root dilatation, and applied for eight weeks. Methylprednisolone- or abatacept-treated mice did not reveal a reduction in aortic root dilatation. In this short time frame, losartan was the only treatment that significantly reduced aorta inflammation, transforming growth factor-beta (TGF-β) signaling and aortic root dilatation rate in these adult Marfan mice. Moreover, the methylprednisolone-treated mice had significantly more aortic alcian blue staining as a marker for aortic damage. Conclusion Anti-inflammatory agents do not reduce the aortic dilatation rate in Marfan mice, but possibly increase aortic damage. Currently, the most promising therapeutic drug in Marfan syndrome is losartan, by blocking the angiotensin II receptor type 1 and thereby inhibiting pSmad2 signaling. PMID:25238161

One-shot versus gradual dilation technique for tract creation in percutaneous nephrolithotomy: a systematic review and meta-analysis.

PubMed

Li, Yutao; Yang, Lu; Xu, Peng; Shen, Pengfei; Qian, Shengqiang; Wei, Wuran; Wang, Jia

2013-10-01

The aim of this study is to evaluate the efficacy and safety of one-shot versus gradual dilation technique for tract creation in percutaneous nephrolithotomy (PCNL). A systematic research of Pubmed, Embase and the Cochrane Library was performed to identify all relevant studies. The quality of the included trials was assessed and the data were extracted independently by two reviewers. The Cochrane Collaboration's Review Manager (RevMan) 5.0.2 software was used for statistical analysis. Four randomized controlled trials were included in analysis involving 346 patients in total. Of these patients 174 were in the one-shot group and 172 in the gradual group. Our meta-analysis showed that there were no significant differences in successful dilation rate [risk ratio (RR): 0.96; 95 % confidence interval (CI): 0.92-1.00, p = 0.05], transfusion rate (RR: 0.62; 95 % CI: 0.20-1.96; p = 0.42), and hemoglobin decrease [mean difference (MD): -0.34; 95 % CI: from -0.67 to -0.00; p = 0.05] between one-shot dilation and gradual dilation. One-shot dilation had significant shorter access time (MD: -1.03; 95 % CI: from -1.57 to -0.49; p = 0.0002) and X-ray exposure time (MD: -42.71; 95 % CI: from -45.05 to -40.37; p < 0.00001) than gradual dilation. Our results show that One-shot dilation is an effective and safe procedure for tract creation in PCNL, with shorter access time and X-ray exposure time and without increased complications. As only four studies with small study populations were available, more high-quality larger trials with longer follow-up are recommended.

Treatment of Ureterointestinal Anastomotic Strictures by Diathermal or Cryoplastic Dilatation

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

Orsi, Franco; Penco, Silvia; Matei, Victor

2007-09-15

Background. Ureterointestinal anastomotic strictures (UAS) complicate 10-15% of surgeries for urinary diversion and are the main cause of deterioration in renal function. Treatments are surgical revision, management with autostatic stent, balloon dilatation, endoscopic incision, and percutaneous transrenal diathermy (Acucise). A new option is cryoplastic dilatation (Polar-Cath). Purpose. To assess the feasibility, complications, and preliminary results of UAS treatment using the Acucise and Polar-Cath systems. Methods. Nineteen UAS, diagnosed by ultrasonography or computed tomography and sequential renal scintigraphy, occurred in 15 cancer patients after radical cystectomy and urinary diversion. Fifteen were managed with balloon diathermy and 4 by balloon cryoplasty inmore » a three-stage procedure-percutaneous nephrostomy, diathermal or cryoplastic dilatation, and transnephrostomic control with nephrostomy removal-each separated by 15 days. All patients gave written informed consent. Results. Dilatations were successful in all cases. The procedure is simple and rapid (about 45 min) under fluoroscopic control and sedation. Procedural complications occurred in 1 (5%) patient with UAS after Wallace II uretero-ileocutaneostomy: a common iliac artery lesion was induced by diathermal dilatation, evident subsequently, and required surgical repair. Patency with balloon diathermy was good, with two restenoses developing over 12 months (range 1-22) of follow-up. With balloon cryoplastic dilatation, one restenosis developed in the short term; follow-up is too brief to assess the long-term efficacy. Conclusion. Our short-term results with diathermal and cryoplastic dilatation to resolve UAS are good. If supported by longer follow-up, the techniques may be considered as first-choice approaches to UAS. Surgery should be reserved for cases in which this minimally invasive technique fails.« less

[Pressure-volume recording of PTCA catheters with balloons of lower and higher compliance].

PubMed

Werner, C; Bloss, P; Kiessling, D; Patzschke, H; Unverdorben, M; Vallbracht, C

1999-11-01

In this report, the results of complementary studies of pressure-volume (p-V) measurements on balloon catheters with balloons of low (LC) and high compliance (HC) used for percutaneous transluminal coronary angioplasty are discussed. The measurements were performed with balloons unconfined in air (free dilatation) and also confined in different shells. In the case of rigid shells, a surprisingly high self-expansion of the catheters was found. Although this self-expansion does not contribute to the radial dilatation, it cannot be neglected, but must be taken into account when the success of balloon dilatation is determined on the basis of measured p-V curves. The investigations performed using wrapped shells clearly show the different dilatation properties of LC and HC balloons. The results provide important information on the feasibility of controlled balloon dilatation on the basis of p-V measurements performed on-line during PTCA.

A case report of percutaneous endoscopic gastrostomy left-side gastropexy to resolve a recurrent gastric dilatation in a dog previously treated with right-side gastropexy for gastric dilatation volvulus.

PubMed

Spinella, Giuseppe; Cinti, Filippo; Pietra, Marco; Capitani, Ombretta; Valentini, Simona

2014-12-01

A 6-year-old, large-breed, female dog was evaluated for gastric dilatation (GD). The dog was affected by GD volvulus, which had been surgically treated with gastric derotation and right incisional gastropexy. Recurrence of GD appeared 36 hours after surgery. The dilatation was immediately treated with an orogastric probe but still recurred 4 times. Therefore, a left-side gastropexy by percutaneous endoscopic gastrostomy (PEG) was performed to prevent intermittent GD. After PEG tube placement, the patient recovered rapidly without side effects. Several techniques of gastropexy have been described as a prophylactic method for gastric dilatation volvulus, but to the authors' knowledge, this is the first report of left-sided PEG gastropexy performed in a case of canine GD recurrence after an incisional right gastropexy. Copyright © 2015 Elsevier Inc. All rights reserved.

Videofluoroscopy-guided balloon dilatation for treatment of severe pharyngeal dysphagia.

PubMed

Yabunaka, Koichi; Konishi, Hideki; Nakagami, Gojiro; Matsuo, Jyunko; Noguchi, Atsushi; Sanada, Hiromi

2015-01-01

Balloon dilatation is a widely accepted technique in the management of esophageal and other types of gastrointestinal strictures, but it is rarely used for the treatment of pharyngeal dysphagia. Therefore, the aim of our prospective study was to evaluate the use of videofluoroscopy-guided balloon dilatation (VGBD) for the treatment of severe pharyngeal dysphagia. The study included 32 stroke patients who had been diagnosed with oral and/or pharyngeal dysphagia. All patients underwent dilatation of the esophageal inlet using a balloon catheter under videofluoroscopic guidance during one or more sessions. Following esophageal dilatation, manual feeding was provided twice weekly. VGBD was effective in 10 out of 32 patients; however, the remaining 22 patients were unable to attempt oral food consumption because aspiration was not completely resolved on videofluoroscopy. According to this case series, VGBD may provide treatment for patients with severe pharyngeal dysphagia, who have not consumed food orally for a long period of time.

A theoretical derivation of the dilatancy equation for brittle rocks based on Maxwell model

NASA Astrophysics Data System (ADS)

Li, Jie; Huang, Houxu; Wang, Mingyang

2017-03-01

In this paper, the micro-cracks in the brittle rocks are assumed to be penny shaped and evenly distributed; the damage and dilatancy of the brittle rocks is attributed to the growth and expansion of numerous micro-cracks under the local tensile stress. A single crack's behaviour under the local tensile stress is generalized to all cracks based on the distributed damage mechanics. The relationship between the local tensile stress and the external loading is derived based on the Maxwell model. The damage factor corresponding to the external loading is represented using the p-alpha ( p- α) model. A dilatancy equation that can build up a link between the external loading and the rock dilatancy is established. A test of dilatancy of a brittle rock under triaxial compression is conducted; the comparison between experimental results and our theoretical results shows good consistency.

Inherited and predisposing factors in the development of gastric dilatation volvulus in dogs.

PubMed

Bell, Jerold S

2014-09-01

This review article summarizes what is known as well as what is undetermined concerning the inherited and environmental pathogenesis of gastric dilatation volvulus in dogs. The disorder primarily affects large and giant, deep-chested breeds. A concise description of a typical dog affected with gastric dilatation volvulus is presented. Copyright © 2014 Elsevier Inc. All rights reserved.

A colon-associated cystic mass occurring in conjunction with cecal dilatation in a Holstein cow

PubMed Central

Garrett, Edgar F.; Singh, Kuldeep

2012-01-01

A 7-year-old Holstein cow was presented for reduced appetite and decreased milk production. Based on physical examination, cecal dilatation was the primary differential diagnosis and was confirmed at surgery. However, in addition to the dilated cecum, 2 large cystic masses were found firmly attached to the proximal loop of the ascending colon. PMID:23729831

A splice site mutation in a gene encoding for PDK4, a mitochondrial protein, is associated with the development of dilated cardiomyopathy in the Doberman pinscher

USDA-ARS?s Scientific Manuscript database

Familial dilated cardiomyopathy is a primary myocardial disease that can result in the development of congestive heart failure and sudden cardiac death. Spontaneous animal models of familial dilated cardiomyopathy exist and the Doberman pinscher dog is one of the most commonly reported canine breeds...

Tachycardia-Induced Right Heart Failure and Severe Tricuspid Regurgitation That Improved with Medication.

PubMed

Yang, Young Ae; Yang, Dong Heon; Kim, Hong Nyun; Kwon, Sang Hoon; Jang, Se Young; Bae, Myung Hwan; Lee, Jang Hoon; Chae, Shung Chull

2015-12-01

Secondary tricuspid regurgitation (TR) primarily develops due to left heart failure or primary pulmonary diseases. Tricuspid annular dilation, which is commonly caused by right ventricular volume and pressure overload followed by right ventricle dilation, is believed to be the main mechanism underlying secondary TR. It is reported that once the tricuspid annulus is dilated, its size cannot spontaneously return to normal, and it may continue to dilate. These reports also suggest the use of an aggressive surgical approach for secondary TR. In the present report, we describe a case of tachycardia-induced severe TR that was completely resolved without the need for surgery.

Eder Puestow dilatation of benign rectal stricture following anterior resection.

PubMed

Woodward, A; Tydeman, G; Lewis, M H

1990-01-01

Benign anastomotic stricture following anterior resection can be difficult to manage when the stricture is proximal. The acceptable surgical options are either a redo low resection with its accompanying hazards or, alternatively, the formation of a permanent colostomy. Although dilatation of such strictures is possible by blind passage of metal bougies, the authors believe that this technique must be regarded as hazardous. A technique of dilatation is described that is usually reserved for esophageal stricture, namely, Eder Puestow dilatation over a guide wire inserted under direct vision. Although this technique may not be without risk, this readily available equipment may be valuable in making a further resection unnecessary.

Multiple Species Comparison of Cardiac Troponin T and Dystrophin: Unravelling the DNA behind Dilated Cardiomyopathy.

PubMed

England, Jennifer; Loughna, Siobhan; Rutland, Catrin Sian

2017-07-07

Animals have frequently been used as models for human disorders and mutations. Following advances in genetic testing and treatment options, and the decreasing cost of these technologies in the clinic, mutations in both companion and commercial animals are now being investigated. A recent review highlighted the genes associated with both human and non-human dilated cardiomyopathy. Cardiac troponin T and dystrophin were observed to be associated with both human and turkey (troponin T) and canine (dystrophin) dilated cardiomyopathies. This review gives an overview of the work carried out in cardiac troponin T and dystrophin to date in both human and animal dilated cardiomyopathy.

Balloon or bougie for dilatation of benign oesophageal stricture? An interim report of a randomised controlled trial.

PubMed Central

Cox, J G; Winter, R K; Maslin, S C; Jones, R; Buckton, G K; Hoare, R C; Sutton, D R; Bennett, J R

1988-01-01

Seventy one patients with benign oesophageal strictures were randomised to receive balloon or bougie dilatation. Sixty five patients were eligible for analysis. At the end of five months the balloon group had significantly more dysphagia and the calibre of the strictures in the balloon group had narrowed by a greater degree. The methods were equally safe and acceptable to patients. While the choice of the method of dilatation depends on the individual patient's needs and operator experience, bougie dilatation is more effective in reducing dysphagia and maintaining stricture patency. Images Fig. 2 Fig. 3 PMID:3065156

Modeling the turbulent kinetic energy equation for compressible, homogeneous turbulence

NASA Technical Reports Server (NTRS)

Aupoix, B.; Blaisdell, G. A.; Reynolds, William C.; Zeman, Otto

1990-01-01

The turbulent kinetic energy transport equation, which is the basis of turbulence models, is investigated for homogeneous, compressible turbulence using direct numerical simulations performed at CTR. It is shown that the partition between dilatational and solenoidal modes is very sensitive to initial conditions for isotropic decaying turbulence but not for sheared flows. The importance of the dilatational dissipation and of the pressure-dilatation term is evidenced from simulations and a transport equation is proposed to evaluate the pressure-dilatation term evolution. This transport equation seems to work well for sheared flows but does not account for initial condition sensitivity in isotropic decay. An improved model is proposed.

Gastric dilatation volvulus: a retrospective study of 203 dogs with ventral midline gastropexy.

PubMed

Ullmann, B; Seehaus, N; Hungerbühler, S; Meyer-Lindenberg, A

2016-01-01

To evaluate the recurrence rate of gastric dilatation volvulus and the incidence of complications in subsequent coeliotomies following ventral midline gastropexy. The medical records of dogs treated for gastric dilatation volvulus by ventral midline gastropexy were retrospectively reviewed. Owners were contacted and invited to complete a questionnaire and to return to the clinic for ultrasonographic and radiographic follow-up. The questionnaire was completed by 203 owners 2 to 123 months postoperatively, 24 of whom attended the follow-up examination. Of the 203 dogs, 13 (6 · 4%) underwent subsequent ventral midline coeliotomy and none developed complications related to the gastropexy site. In 23 of the 24 re-evaluated dogs, the stomach was closely associated with the abdominal on radiography and/or ultrasound. The recurrence rate for clinical signs of gastric dilatation or gastric dilatation volvulus after ventral midline gastropexy was 6 · 4%. This study shows that the recurrence of gastric dilatation volvulus after ventral midline gastropexy is low and adhesion of the stomach to the abdominal wall is persistent in almost all dogs that were re-examined. The gastropexy site did not appear to interfere with subsequent coeliotomy. © 2015 British Small Animal Veterinary Association.

A texture analysis method for MR images of airway dilator muscles: a feasibility study

PubMed Central

Järnstedt, J; Sikiö, M; Viik, J; Dastidar, P; Peltomäki, T; Eskola, H

2014-01-01

Objectives: Airway dilator muscles play an important role in the analysis of breathing-related symptoms, such as obstructive sleep apnoea. Texture analysis (TA) provides a new non-invasive method for analysing airway dilator muscles. In this study, we propose a TA methodology for airway dilator muscles and prove the robustness of this method. Methods: 15 orthognathic surgery patients underwent 3-T MRI. Computerized TA was performed on 20 regions of interest (ROIs) in the patients' airway dilator muscles. 53 texture parameters were calculated for all ROIs. The robustness of the TA method was analysed by altering the locations, sizes and shapes of the ROIs. Results: Our study shows that there is significant difference in TA results as the size or shape of ROI changes. The change of location of the ROI inside the studied muscle does not affect the TA results. Conclusions: The TA method is valid for airway dilator muscles. We propose a methodology in which the number of co-occurrence parameters is reduced by using mean values from four different directions (0°, 45°, 90° and 135°) with pixel spacing of 1 pixel. PMID:24773626

Balloon catheter dilation and nasolacrimal duct intubation for treatment of nasolacrimal duct obstruction after failed probing.

PubMed

Repka, Michael X; Chandler, Danielle L; Holmes, Jonathan M; Hoover, Darren L; Morse, Christine L; Schloff, Susan; Silbert, David I; Tien, D Robbins

2009-05-01

To compare the outcomes of balloon catheter dilation and nasolacrimal intubation as treatment for congenital nasolacrimal duct obstruction after failed probing in children younger than 4 years. We conducted a prospective, nonrandomized, multicenter study that enrolled 159 children aged 6 months to younger than 48 months who had a history of a single failed nasolacrimal duct probing and at least 1 of the following clinical signs of nasolacrimal duct obstruction: epiphora, mucous discharge, or increased tear lake. One hundred ninety-nine eyes underwent either balloon catheter nasolacrimal duct dilation or nasolacrimal duct intubation. Treatment success was defined as absence of epiphora, mucous discharge, or increased tear lake at the outcome visit 6 months after surgery. Treatment success was reported in 65 of 84 eyes (77%; 95% confidence interval, 65%-85%) in the balloon catheter dilation group compared with 72 of 88 eyes (84% after adjustment for intereye correlation; 74%-91%) in the nasolacrimal intubation group (risk ratio for success for intubation vs balloon dilation, 1.08; 0.95-1.22). Both balloon catheter dilation and nasolacrimal duct intubation alleviate the clinical signs of persistent nasolacrimal duct obstruction in a similar percentage of patients.

Dilation of fusion pores by crowding of SNARE proteins

PubMed Central

Wu, Zhenyong; Bello, Oscar D; Thiyagarajan, Sathish; Auclair, Sarah Marie; Vennekate, Wensi; Krishnakumar, Shyam S; O'Shaughnessy, Ben; Karatekin, Erdem

2017-01-01

Hormones and neurotransmitters are released through fluctuating exocytotic fusion pores that can flicker open and shut multiple times. Cargo release and vesicle recycling depend on the fate of the pore, which may reseal or dilate irreversibly. Pore nucleation requires zippering between vesicle-associated v-SNAREs and target membrane t-SNAREs, but the mechanisms governing the subsequent pore dilation are not understood. Here, we probed the dilation of single fusion pores using v-SNARE-reconstituted ~23-nm-diameter discoidal nanolipoprotein particles (vNLPs) as fusion partners with cells ectopically expressing cognate, 'flipped' t-SNAREs. Pore nucleation required a minimum of two v-SNAREs per NLP face, and further increases in v-SNARE copy numbers did not affect nucleation rate. By contrast, the probability of pore dilation increased with increasing v-SNARE copies and was far from saturating at 15 v-SNARE copies per face, the NLP capacity. Our experimental and computational results suggest that SNARE availability may be pivotal in determining whether neurotransmitters or hormones are released through a transient ('kiss and run') or an irreversibly dilating pore (full fusion). DOI: http://dx.doi.org/10.7554/eLife.22964.001 PMID:28346138

Endoscopic management for congenital esophageal stenosis: A systematic review.

PubMed

Terui, Keita; Saito, Takeshi; Mitsunaga, Tetsuya; Nakata, Mitsuyuki; Yoshida, Hideo

2015-03-16

Congenital esophageal stenosis (CES) is an extremely rare malformation, and standard treatment have not been completely established. By years of clinical research, evidence has been accumulated. We conducted systematic review to assess outcomes of the treatment for CES, especially the role of endoscopic modalities. A total of 144 literatures were screened and reviewed. CES was categorized in fibromuscular thickening, tracheobronchial remnants (TBR) and membranous web, and the frequency was 54%, 30% and 16%, respectively. Therapeutic option includes surgery and dilatation, and surgery tends to be reserved for ineffective dilatation. An essential point is that dilatation for TBR type of CES has low success rate and high rate of perforation. TBR can be distinguished by using endoscopic ultrasonography (EUS). Overall success rate of dilatation for CES with or without case selection by using EUS was 90% and 29%, respectively. Overall rate of perforation with or without case selection was 7% and 24%, respectively. By case selection using EUS, high success rate with low rate of perforation could be achieved. In conclusion, endoscopic dilatation has been established as a primary therapy for CES except TBR type. Repetitive dilatation with gradual step-up might be one of safe ways to minimize the risk of perforation.

Endoscopic management for congenital esophageal stenosis: A systematic review

PubMed Central

Terui, Keita; Saito, Takeshi; Mitsunaga, Tetsuya; Nakata, Mitsuyuki; Yoshida, Hideo

2015-01-01

Congenital esophageal stenosis (CES) is an extremely rare malformation, and standard treatment have not been completely established. By years of clinical research, evidence has been accumulated. We conducted systematic review to assess outcomes of the treatment for CES, especially the role of endoscopic modalities. A total of 144 literatures were screened and reviewed. CES was categorized in fibromuscular thickening, tracheobronchial remnants (TBR) and membranous web, and the frequency was 54%, 30% and 16%, respectively. Therapeutic option includes surgery and dilatation, and surgery tends to be reserved for ineffective dilatation. An essential point is that dilatation for TBR type of CES has low success rate and high rate of perforation. TBR can be distinguished by using endoscopic ultrasonography (EUS). Overall success rate of dilatation for CES with or without case selection by using EUS was 90% and 29%, respectively. Overall rate of perforation with or without case selection was 7% and 24%, respectively. By case selection using EUS, high success rate with low rate of perforation could be achieved. In conclusion, endoscopic dilatation has been established as a primary therapy for CES except TBR type. Repetitive dilatation with gradual step-up might be one of safe ways to minimize the risk of perforation. PMID:25789088

A Comparison of Over-the-Counter Mechanical Nasal Dilators: A Systematic Review.

PubMed

Kiyohara, Nicole; Badger, Christopher; Tjoa, Tjoson; Wong, Brian

2016-09-01

The internal nasal valve is the narrowest part of the nasal airway and a common site of inspiratory collapse and obstruction of nasal airflow. Over-the-counter mechanical nasal dilators are an alternative to surgical intervention that attempts to improve airflow through the internal nasal valve. To determine the efficacy of over-the-counter mechanical nasal dilators and classify these products by mechanism. A database of 33 available over-the-counter mechanical nasal dilators was generated via a PubMed search as well as an internet search via Amazon.com and Google, conducted from April 1, 2013, through December 31, 2015. Products determined to be unavailable or discontinued were excluded from the database. Of the devices examined in published literature, efficacy was based on objective measures, such as measured airflow, the cross-sectional area of the nasal valve, and changes in resistance. Measures of reported sleep quality or patient perception were excluded. An analysis of each product's mechanism revealed 4 broad classes: external nasal dilator strips, nasal stents, nasal clips, and septal stimulators. A review demonstrated 5 studies supporting the use of external nasal dilator strips, 4 studies supporting the use of nasal clips, 1 study supporting the use of nasal stents, and no studies supporting the use of septal stimulators. Our findings suggest that external nasal dilator strips and nasal clips effectively relieve obstruction of the internal nasal valve and may be an alternative to surgical intervention in some patients.

Impact of sickle cell anaemia on cardiac chamber size in the paediatric population.

PubMed

Adjagba, Philippe M; Habib, Gaston; Robitaille, Nancy; Pastore, Yves; Raboisson, Marie-Josée; Curnier, Daniel; Dahdah, Nagib

2017-07-01

Purpose Sickle cell disease is known to cause various degrees of vasculopathy, including impact on heart function. The aims of this single-centre, retrospective study were to assess cardiac chamber size and function and the relationship with haematological indices such as haemoglobin, aspartate aminotransferase, reticulocytosis and bilirubin, lactate dehydrogenase in sickle cell disease. Right ventricle and left ventricle diastolic diameters, left ventricle mass estimate, left ventricle shortening fraction, myocardial performance index, and an index of myocardial relaxation (E/E') were calculated and correlated with haematological parameters. A total of 110 patients (65% haemoglobin SS, 29% haemoglobin SC) were studied at a mean age of 12.14±5.26 years. Right ventricle dilatation and left ventricle dilatation were present in 61.5 and 42.9%, respectively. Left ventricle mass was abnormal in 21.9%; all patients had normal myocardial performance index, 31.4% had abnormal E/E', and left ventricle shortening fraction was low in 38.1%. Cardiac dilatation was best correlated with haemoglobin, aspartate aminotransferase, reticulocytosis and bilirubin. Best subset regression analysis yielded significant additional prediction for right ventricle or left ventricle dilatation with haemoglobin, bilirubin, and lactate dehydrogenase. Abnormal E/E' was solely predictable with haemoglobin level. Hydroxyurea-treated patients had improved diastolic function. Right ventricle dilatation was more prevalent than left ventricle dilatation. The long-term consequences of right ventricular dilatation, clinical consequences, and association with pulmonary vasculopathy need to be further determined.

Using the adaptive SMA composite cylinder concept to reduce radial dilation in composite pressure vessels

NASA Astrophysics Data System (ADS)

Paine, Jeffrey S.; Rogers, Craig A.

1995-05-01

Composite materials are widely used in the design of pressurized gas and fluid vessels for applications ranging from underground gasoline storage tanks to rocket motors for the space shuttle. In the design of a high pressure composite vessel (Pi > 12 Ksi), thick-wall (R/h < 15) vessels are required. For efficient material use in composite material vessels, the radial dilation (expansion or swelling) of the composite vessel can often approach values nearing 2 percent of the diameter. Over long periods of internal pressure loading over elevated temperatures, composite material cylinders may also experience substantial creep. The short term dilation and long term creep are not problematic for applications requiring only the containment of the pressurized fluid. In applications where metallic liners are required, however, substantial dilation and creep causes plastic yielding which leads to reduced fatigue life. To applications such as a hydraulic accumulator, where a piston is employed to fit and seal the fluid in the composite cylinder, the dilation and creep may allow leakage and pressure loss around the piston. A concept called the adaptive composite cylinder is experimentally presented. Shape memory alloy wire in epoxy resin is wrapped around or within polymer matrix composite cylinders to reduce radial dilation of the cylinder. Experimental results are presented that demonstrate the ability of the SMA wire layers to reduce radial dilation. Results from experimental testing of the recovery stress fatigue response of nitinol shape memory alloy wires is also presented.

Effects of soil aggregates on debris-flow mobilization: Results from ring-shear experiments

USGS Publications Warehouse

Iverson, Neal R.; Mann, Janet E.; Iverson, Richard M.

2010-01-01

Rates and styles of landslide motion are sensitive to pore-water pressure changes caused by changes in soil porosity accompanying shear deformation. Soil may either contract or dilate upon shearing, depending upon whether its initial porosity is greater or less, respectively, than a critical-state porosity attained after sufficiently high strain. We observed complications in this behavior, however, during rate-controlled (0.02 m s−1) ring-shear experiments conducted on naturally aggregated dense loamy sand at low confining stresses (10.6 and 40 kPa). The aggregated soil first dilated and then contracted to porosities less than initial values, whereas the same soil with its aggregates destroyed monotonically dilated. We infer that aggregates persisted initially during shear and caused dilation before their eventual breakdown enabled net contraction. An implication of this contraction, demonstrated in experiments in which initial soil porosity was varied, is that the value of porosity distinguishing initially contractive from dilative behavior can be significantly larger than the critical-state porosity, which develops only after disaggregation ceases at high strains. In addition, post-dilative contraction may produce excess pore pressures, thereby reducing frictional strength and facilitating debris-flow mobilization. We infer that results of triaxial tests, which generally produce strains at least a factor of ∼ 4 smaller than those we observed at the inception of post-dilative contraction, do not allow soil contraction to be ruled out as a mechanism for debris-flow mobilization in dense soils containing aggregates.

Balloon dilation of the cartilaginous eustachian tube.

PubMed

Poe, Dennis S; Silvola, Juha; Pyykkö, Ilmari

2011-04-01

(1) To translate techniques developed in a previous cadaver study of balloon dilation of the cartilaginous eustachian tube (ET) into clinical treatment for refractory dilatory dysfunction and (2) to study the safety/efficacy of the technique in a pilot clinical trial. Prospective with subjects as their own historical controls since June 2009. Regional academic center. Eleven consecutive adult patients with longstanding otitis media with effusion (OME) who were unable to autoinsufflate their ET by Valsalva, swallow, or yawn and who had previous tympanostomies (average, 4.7). At the time of intervention, 5 of 11 had a tube; 2 of 11 had a tympanic membrane (TM) perforation. Four of 11 had intact TMs, 2 with OME and tympanogram type B and 2 with TM retraction and tympanogram types B and C. Balloon dilation of the cartilaginous ET was performed with sinus dilation instruments via transnasal endoscopic approach under general anesthesia in a day surgery setting. Inflation was to a maximum of 12 atm for 1 minute. ability to Valsalva, rating of ET mucosal inflammation, tympanogram, and otomicroscopy findings. All cases successfully dilated. Eleven of 11 could self-insufflate by Valsalva (P < .001); tympanograms were A (4/11), C (1/11), or open (6/11). All atelectases resolved. Procedures were well tolerated, without pain or complications related to dilation. Dilation of the cartilaginous ET appeared to be beneficial and without significant adverse effects in the treatment of ET dilatory dysfunction. Larger controlled trials with long-term results are now justified and needed.

Influence of mechanically-induced dilatation on the shape memory behavior of amorphous polymers at large deformation

NASA Astrophysics Data System (ADS)

Hanzon, Drew W.; Lu, Haibao; Yakacki, Christopher M.; Yu, Kai

2018-01-01

In this study, we explore the influence of mechanically-induced dilatation on the thermomechanical and shape memory behavior of amorphous shape memory polymers (SMPs) at large deformation. The uniaxial tension, glass transition, stress relaxation and free recovery behaviors are examined with different strain levels (up to 340% engineering strain). A multi-branched constitutive model that incorporates dilatational effects on the polymer relaxation time is established and applied to assist in discussions and understand the nonlinear viscoelastic behaviors of SMPs. It is shown that the volumetric dilatation results in an SMP network with lower viscosity, faster relaxation, and lower Tg. The influence of the dilatational effect on the thermomechanical behaviors is significant when the polymers are subject to large deformation or in a high viscosity state. The dilation also increases the free recovery rate of SMP at a given recovery temperature. Even though the tested SMPs are far beyond their linear viscoelastic region when a large programming strain is applied, the free recovery behavior still follows the time-temperature superposition (TTSP) if the dilatational effect is considered during the transformation of time scales; however, if the programming strain is different, TTSP fails in predicting the recovery behavior of SMPs because the network has different entropy state and driving force during shape recovery. Since most soft active polymers are subject to large deformation in practice, this study provides a theoretical basis to better understand their nonlinear viscoelastic behaviors, and optimize their performance in engineering applications.

Morphological alterations within the peripheral fixation of the iris dilator muscle in eyes with pigmentary glaucoma.

PubMed

Flügel-Koch, Cassandra M; Tektas, Ozan Y; Kaufman, Paul L; Paulsen, Friedrich P; Lütjen-Drecoll, Elke

2014-06-17

To analyze the peripheral fixation of the iris dilator muscle in normal eyes and in eyes with pigmentary glaucoma (PG). Using 63 control eyes (age 18 months-99 years), the peripheral iris dilator was investigated by light microscopy, immunohistochemistry, and electron microscopy. Development was studied using 18 differently aged fetal eyes stained immunohistochemically against α-smooth muscle (SM) actin. The peripheral iris dilator muscle in PG was analyzed using semithin and ultrathin sections of six glutaraldehyde-fixed eyes from three donors aged 38, 62, and 74 years. In normal eyes, the peripheral end of the iris dilator muscle is arranged in a sphincter-like manner. Arcade-shaped tendinous connections associated with myofibroblasts (iridial strands) anchor the iris dilator within the elastic-fibromuscular ciliary meshwork that also serves as fixation area for the elastic tendons of the inner ciliary muscle portions. The iridial strands are innervated and can adapt their length during accommodation. The PG eyes show incomplete circular bundles and iridial strands that are mainly anchored to the iris stroma and the flexible uveal parts of the trabecular meshwork. The normal anchorage of the peripheral iris dilator and its presumably neuronally regulated length adaptation stabilize the peripheral iris during accommodation. Insufficient fixation in PG could promote posterior bowing of the iris with rubbing against the zonular fibers and pigment liberation from the iris pigmented epithelium. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Esophageal dilation in head and neck cancer patients: A systematic review and meta-analysis.

PubMed

Moss, William J; Pang, John; Orosco, Ryan K; Weissbrod, Philip A; Brumund, Kevin T; Weisman, Robert A; Brigger, Matthew T; Coffey, Charles S

2018-01-01

To characterize the safety profile and effectiveness of esophageal dilation in head and neck cancer patients. A systematic review was undertaken for articles reporting outcomes of esophageal dilation in head and neck cancer patients. The Medline, Scopus, Web of Science, and Cochrane databases were searched in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Complications related to esophageal dilation in head and neck cancer patients was the primary outcome of interest. Success rates, demographic data, cancer staging, and treatment data were assessed secondarily. Statistical analyses included both qualitative and quantitative assessments. A limited meta-analysis and pooling of the data was performed using a random effects model. Of the collective 8,243 initial candidate articles, 15 retrospective studies containing data for a collective 449 patients were ultimately included in the analysis. There was significant heterogeneity in the outcomes data. With an overall complication rate of 10.6% (95% confidence interval [CI]: 4.1%,17%) and a pooled success rate of 72.9% (95% CI: 65.7%,80.1%) per patient, the articles generally supported the use of dilation. Head and neck cancer patients experience a higher rate of complications following dilation compared to patients with other causes of benign stricture. Esophageal dilation is effective in improving dysphagia, but these benefits are often transient and thus necessitate repeat interventions. Laryngoscope, 128:111-117, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

[Conservative treatment of benign esophageal strictures using dilation. Analysis of 500 cases].

PubMed

Andreollo, N A; Lopes, L R; Inogutti, R; Brandalise, N A; Leonardi, L S

2001-01-01

The benign esophageal stenoses (BES) are common complications owing to many etiologies: gastroesophageal reflux, ingestion of corrosive agents, esophageal surgery, radiotherapy, postendoscopic variceal sclerotherapy, drug ingestion, prolonged nasogastric intubation, extrinsic compression and esophageal webs. Esophageal dilatations are worldwide recommended to treat this complication, employing dilators of many types and diameters and facilitating the food ingestion. Evaluation of the results and advantages of the conservative treatment of the BES using esophageal dilatations, in outpatient service of upper digestive endoscopy. During the period from 1981 to 1999, 500 patients with BES were treated and followed up at the Gastrocenter - UNICAMP, in an individually Program of Esophageal Dilatation for each case. The highest number of cases was under ages from 31 to 60 years old (52,8%), and males (59,2%). The most predominant etiologies were: peptic stenosis (30,4%), caustic ingestion (23,6%), anastomosis (23,2%), megaesophagus (8,0%) and prolonged nasogastric ingestion entubation (6,4%), totalizing 91,6% of the BES. Most of patients (94,2%) were submitted to the maximum of 25 dilations. Dilators from 10,5 to 16 mm were employed in 95,6% of the cases. The duration of the treatment was 24 months in 76,2% of the BES. Esophageal perforations occurred in 6 patients (1,2%), without mortality. Were considered excellent, good and bad results, respectively in 76,2%, 18,2% and 5,6% of the cases. On the other hand, excellent results were recorded in 81,0% of the peptic stenosis, 66,1% of the caustic stenosis and 82,7% of the anastomotic stenosis. The conservative treatment failed in 9,3% of the caustic stenosis, 4,3% of the anastomotic stenosis and 3,9% of the peptic stenosis. Thus, the caustic stenosis were unsuccessfull in the highest percentage of unsuccessful. The conservative treatment using guidewire dilators (Savary-Gilliard and Eder-Puestow) is the first choice in the BES, is effective for long time, with short complications and the surgical treatment is indicated only when the dilatations failed.

Percutaneous Transhepatic Cutting Balloon Papillotomy for Removal of Common Bile Duct Stones

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

Oguzkurt, Levent, E-mail: loguzkurt@yahoo.com; Ozkan, Ugur; Gumus, Burcak

2009-09-15

We report the case of a 66-year-old female who presented with jaundice secondary to recurrent adenocarcinoma of the gallbladder and several common bile duct stones. Percutaneous papillary dilatation was planned to remove the common bile duct stones. Papilla was dilated through the percutaneous approach with an 8-mm peripheral cutting balloon instead of a standard balloon. All the stones were pushed successfully into the duodenum with a saline flush. No complications were encountered. Use of a peripheral cutting balloon for dilatation of the papilla seems to be safe and effective because it has the advantage of controlled incision and dilatation ofmore » the target at low pressures.« less

Multiple Species Comparison of Cardiac Troponin T and Dystrophin: Unravelling the DNA behind Dilated Cardiomyopathy

PubMed Central

England, Jennifer

2017-01-01

Animals have frequently been used as models for human disorders and mutations. Following advances in genetic testing and treatment options, and the decreasing cost of these technologies in the clinic, mutations in both companion and commercial animals are now being investigated. A recent review highlighted the genes associated with both human and non-human dilated cardiomyopathy. Cardiac troponin T and dystrophin were observed to be associated with both human and turkey (troponin T) and canine (dystrophin) dilated cardiomyopathies. This review gives an overview of the work carried out in cardiac troponin T and dystrophin to date in both human and animal dilated cardiomyopathy. PMID:29367539

Transforming Growth Factor Beta-2 Mutations in Barlow's Disease and Aortic Dilatation.

PubMed

Disha, Kushtrim; Schulz, Solveig; Kuntze, Thomas; Girdauskas, Evaldas

2017-07-01

We report on a patient operated on for degenerative myxomatous mitral and tricuspid valve disease (Barlow's disease) and aortic root dilatation. A valve repair operation and the postoperative course were uneventful. Multigenerational genetic analyses revealed two different mutations in the transforming growth factor beta-2 gene in the same patient. The two mutations in different exons were inherited from both parents each. None of the parents presented with either valve dysfunction or aortic root dilatation. This rare case illustrates potentially common genetic and signaling pathways of concomitant myxomatous valve disease and aortic root dilatation. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Assessing first-stage labor progression and its relationship to complications.

PubMed

Hamilton, Emily F; Warrick, Philip A; Collins, Kathleen; Smith, Samuel; Garite, Thomas J

2016-03-01

New labor curves have challenged the traditional understanding of the general pattern of dilation and descent in labor. They also revealed wide variation in the time to advance in dilation. An interval of arrest such as 4 hours did not fall beyond normal limits until dilation had reached 6 cm. Thus, the American College of Obstetricians and Gynecologists/Society for Maternal-Fetal Medicine first-stage arrest criteria, based in part on these findings, are applicable only in late labor. The wide range of time to dilate is unavoidable because cervical dilation has neither a precise nor direct relationship to time. Newer statistical techniques (multifactorial models) can improve precision by incorporating several factors that are related directly to labor progress. At each examination, the calculations adapt to the mother's current labor conditions. They produce a quantitative assessment that is expressed in percentiles. Low percentiles indicate potentially problematic labor progression. The purpose of this study was to assess the relationship between first-stage labor progress- and labor-related complications with the use of 2 different assessment methods. The first method was based on arrest of dilation definitions. The other method used percentile rankings of dilation or station based on adaptive multifactorial models. We included all 4703 cephalic-presenting, term, singleton births with electronic fetal monitoring and cord gases at 2 academic community referral hospitals in 2012 and 2013. We assessed electronic data for route of delivery, all dilation and station examinations, newborn infant status, electronic fetal monitoring tracings, and cord blood gases. The labor-related complication groups included 272 women with cesarean delivery for first-stage arrest, 558 with cesarean delivery for fetal heart rate concerns, 178 with obstetric hemorrhage, and 237 with neonatal depression, which left 3004 women in the spontaneous vaginal birth group. Receiver operating characteristic curves were constructed for each assessment method by measurement of the sensitivity for each complication vs the false-positive rate in the normal reference group. The duration of arrest at ≥6 cm dilation showed poor levels of discrimination for the cesarean delivery interventions (area under the curve, 0.55-0.65; P < .01) and no significant relationship to hemorrhage or neonatal depression. The dilation and station percentiles showed high discrimination for the cesarean delivery-related outcomes (area under the curve, 0.78-0.93; P < .01) and low discrimination for the clinical outcomes of hemorrhage and neonatal depression (area under the curve, 0.58-0.61; P < .01). Duration of arrest of dilation at ≥6 cm showed little or no discrimination for any of the complications. In comparison, percentile rankings that were based on the adaptive multifactorial models showed much higher discrimination for cesarean delivery interventions and better, but low discrimination for hemorrhage. Adaptive multifactorial models present a different method to assess labor progress. Rather than "pass/fail" criteria that are applicable only to dilation in late labor, they produce percentile rankings, assess 2 essential processes for vaginal birth (dilation and descent), and can be applied from 3 cm onward. Given the limitations of labor-progress assessment based solely on the passage of time and because of the extreme variation in decision-making for cesarean delivery for labor disorders, the types of mathematic analyses that are described in this article are logical and promising steps to help standardize labor assessment. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Regional Slip Tendency Analysis of the Great Basin Region

DOE Data Explorer

Faulds, James E.

2013-09-30

Slip and dilation tendency on the Great Basin fault surfaces (from the USGS Quaternary Fault Database) were calculated using 3DStress (software produced by Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by the measured ambient stress field. - Values range from a maximum of 1 (a fault plane ideally oriented to slip or dilate under ambient stress conditions) to zero (a fault plane with no potential to slip or dilate). - Slip and dilation tendency values were calculated for each fault in the Great Basin. As dip is unknown for many faults in the USGS Quaternary Fault Database, we made these calculations using the dip for each fault that would yield the maximum slip or dilation tendency. As such, these results should be viewed as maximum slip and dilation tendency. - The resulting along‐fault and fault‐to‐fault variation in slip or dilation potential is a proxy for along fault and fault‐to‐fault variation in fluid flow conduit potential. Stress Magnitudes and directions were calculated across the entire Great Basin. Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998 Robertson‐Tait et al., 2004; Hickman and Davatzes, 2010; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012; Moeck et al., 2010; Moos and Ronne, 2010 and Reinecker et al., 2005). The minimum horizontal stress direction (Shmin) was contoured, and spatial bins with common Shmin directions were calculated. Based on this technique, we subdivided the Great Basin into nine regions (Shmin <070, 070140). Slip and dilation tendency were calculated using 3DStress for the faults within each region using the mean Shmin for the region. Shmin variation throughout Great Basin are shown on Figure 3. For faults within the Great Basin proper, we applied a normal faulting stress regime, where the vertical stress (sv) is larger than the maximum horizontal stress (shmax), which is larger than the minimum horizontal stress (sv>shmax>shmin). Based on visual inspection of the limited stress magnitude data in the Great Basin, we used magnitudes such that shmin/shmax = .527 and shmin/sv= .46. These values are consistent with stress magnitude data at both Dixie Valley (Hickman et al., 2000) and Yucca Mountain (Stock et al., 1985). For faults within the Walker Lane/Eastern California Shear Zone, we applied a strike‐slip faulting stress, where shmax > sv > shmin. Upon visual inspection of limited stress magnitude data from the Walker Lane and Eastern California Shear zone, we chose values such that SHmin/SHmax = .46 and Shmin/Sv= .527 representative of the region. Results: The results of our slip and dilation tendency analysis are shown in Figures 4 (dilation tendency), 5 (slip tendency) and 6 (slip tendency + dilation tendency). Shmin varies from northwest to east‐west trending throughout much of the Great Basin. As such, north‐ to northeast‐striking faults have the highest tendency to slip and to dilate, depending on the local trend of shmin. These results provide a first order filter on faults and fault systems in the Great Basin, affording focusing of local‐scale exploration efforts for blind or hidden geothermal resources.

Incidence of gastric dilatation-volvulus following a splenectomy in 238 dogs.

PubMed

Maki, Lynn C; Males, Kristina N; Byrnes, Madeline J; El-Saad, Anthony A; Coronado, George S

2017-12-01

There is contradicting information in the veterinary literature regarding canine splenectomy and the increased risk for subsequent gastric dilatation-volvulus. The main purpose of this study was to determine the rate of occurrence of gastric dilatation-volvulus following splenectomy in medium to large breed dogs compared with a control group undergoing other abdominal procedures. Follow-up was performed by reviewing the medical records and conducting phone interviews. Weight, gender, and presence of a hemoabdomen at the time of surgery were not significantly associated with occurrence of gastric dilatation-volvulus, while increasing age was. Ten of 238 (4%) dogs in the splenectomy group and 3/209 (1.4%) dogs in the control group subsequently developed gastric dilatation-volvulus, which was not significantly different ( P = 0.08). While the findings approach significance and support a need for future investigation, the current recommendation for gastropexy at time of splenic removal should be made on a case by case basis and while considering previously documented risk factors.

Eustachian Tube Dilation via a Transtympanic Approach in 6 Cadaver Heads: A Feasibility Study.

PubMed

Dean, Marc; Chao, Wei-Chieh; Poe, Dennis

2016-10-01

The goal of this study was to evaluate the feasibility of endoscopic transtympanic balloon dilation of the cartilaginous eustachian tube. To accomplish this, transtympanic balloon dilation of the cartilaginous eustachian tube was performed on 11 eustachian tubes (6 cadaver heads). The balloon catheter was introduced and passed through the protympanic orifice of the eustachian tube transtympanically under endoscopic view and cannulated without incident in all cadavers. Computed tomography was then performed postprocedure to evaluate for inadvertent dilation of the bony eustachian tube, adverse placement of the balloon, or any bony fractures. The balloon was seen to be successfully inflated in the cartilaginous portion without damage to surrounding structures in all cases. This demonstrates that under endoscopic guidance, the protympanic orifice of the eustachian tube can be feasibly cannulated and reliably traversed, allowing for targeted dilation of the cartilaginous eustachian tube from a transtympanic approach. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

Porous media modeling and micro-structurally motivated material moduli determination via the micro-dilatation theory

NASA Astrophysics Data System (ADS)

Jeong, J.; Ramézani, H.; Sardini, P.; Kondo, D.; Ponson, L.; Siitari-Kauppi, M.

2015-07-01

In the present contribution, the porous material modeling and micro-structural material parameters determination are scrutinized via the micro-dilatation theory. The main goal is to take advantage of the micro-dilatation theory which belongs to the generalized continuum media. In the first stage, the thermodynamic laws are entirely revised to reach the energy balance relation using three variables, deformation, porosity change and its gradient underlying the porous media as described in the micro-dilatation theory or so-called void elasticity. Two experiments over cement mortar specimens are performed in order to highlight the material parameters related to the pore structure. The shrinkage due to CO2 carbonation, porosity and its gradient are calculated. The extracted values are verified via 14C-PMMA radiographic image method. The modeling of swelling phenomenon of Delayed Ettringite Formation (DEF) is studied later on. This issue is performed via the crystallization pressure application using the micro-dilatation theory.

Percutaneous nephrolithotomy with one-shot dilation method: Is it safe in patients who had open surgery before?

PubMed

Süelözgen, Tufan; Isoglu, Cemal Selcuk; Turk, Hakan; Yoldas, Mehmet; Karabicak, Mustafa; Ergani, Batuhan; Boyacioglu, Hayal; Ilbey, Yusuf Ozlem; Zorlu, Ferruh

2016-01-01

This study aimed to evaluate whether one-shot dilatation technique is as safe in patients with a history of open-stone surgery as it is in patients without previous open-stone surgery. Between January 2007 and February 2015, 82 patients who underwent percutaneous nephrolithotomy (PNL) surgery with one-shot dilation technique who previously had open-stone surgery were retrospectively reviewed and evaluated (Group 1). Another 82 patients were selected randomly among patients who had PNL with one-shot dilation technique, but with no history of open renal surgery (Group 2). Age, gender, type of kidney stone, duration of surgery, radiation exposure time, and whether or not there was any bleeding requiring perioperative and postoperative transfusion were noted for each patient. The stone-free rates, operation and fluoroscopy time, and peroperative and postoperative complication rates were similar in both groups (p>0.05). Our experience indicated that PNL with one-shot dilation technique is a reliable method in patients with a history of open-stone surgery.

Left coronary aneurysmal dilation and subaortic stenosis in a dog.

PubMed

Hernandez, Juan L; Bélanger, Marie-Claude; Benoit-Biancamano, Marie-Odile; Girard, Christiane; Pibarot, Philippe

2008-06-01

A 6-month-old German shepherd dog was referred for evaluation of a cardiac murmur. Upon physical examination, the auscultated heart rate was 120 beats/min, and a grade IV/VI systolic heart murmur with a point of maximal intensity over the left heart base radiating up the neck was heard. The standard echocardiographic examination showed subaortic stenosis and an anechoic tubular structure extending from the sinus of Valsalva to the left ventricular posterior wall. Aneurysmal left coronary artery (CA) was confirmed by angiography. The dog was euthanized and post-mortem examination showed severe dilatation of the proximal left CA and confirmed the subaortic stenosis. Histopathology did not demonstrate abnormalities in the walls of the CA, aorta or pulmonary artery. The exact cause of the CA aneurysmal dilation remains unknown. Subaortic stenosis, elevated coronary vascular resistance or a congenital anomaly may have contributed to the dilation. To our knowledge, coronary aneurysmal dilation has never been described in dogs. Standard echocardiography provides reliable information on coronary anatomy.

Congenital dilatation of the intrahepatic bile ducts associated with the development of amyloidosis

PubMed Central

Fevery, J.; Tanghe, W.; Kerremans, R.; Desmet, V.; De Groote, J.

1972-01-01

Two cases of pure congenital dilatation of the intrahepatic bile ducts are presented. One patient developed amyloidosis secondary to suppuration, and had isolated cysts in the renal medulla. The position of congenital dilatation of the intrahepatic bile ducts compared with cysts in the liver and its association with `cystic' diseases of the kidneys is discussed. ImagesFig. 1Fig. 2Fig. 3Fig. 4 PMID:5077171

Colonic strictures: dilation and stents.

PubMed

Adler, Douglas G

2015-04-01

Colonic strictures, both benign and malignant, are commonly encountered in clinical practice. Benign strictures are most commonly treated by balloon dilation and less frequently with stents. Balloon dilation can help forestall or obviate surgery in some patients. Colonic strictures of malignant etiology generally need to be managed by stents and/or surgery. This article reviews endoscopic approaches to the management of colonic strictures. Copyright © 2015 Elsevier Inc. All rights reserved.

Cardiothoracic ratio for prediction of left ventricular dilation: a systematic review and pooled analysis.

PubMed

Loomba, Rohit S; Shah, Parinda H; Nijhawan, Karan; Aggarwal, Saurabh; Arora, Rohit

2015-03-01

Increased cardiothoracic ratio noted on chest radiographs often prompts concern and further evaluation with additional imaging. This study pools available data assessing the utility of cardiothoracic ratio in predicting left ventricular dilation. A systematic review of the literature was conducted to identify studies comparing cardiothoracic ratio by chest x-ray to left ventricular dilation by echocardiography. Electronic databases were used to identify studies which were then assessed for quality and bias, with those with adequate quality and minimal bias ultimately being included in the pooled analysis. The pooled data were used to determine the sensitivity, specificity, positive predictive value and negative predictive value of cardiomegaly in predicting left ventricular dilation. A total of six studies consisting of 466 patients were included in this analysis. Cardiothoracic ratio had 83.3% sensitivity, 45.4% specificity, 43.5% positive predictive value and 82.7% negative predictive value. When a secondary analysis was conducted with a pediatric study excluded, a total of five studies consisting of 371 patients were included. Cardiothoracic ratio had 86.2% sensitivity, 25.2% specificity, 42.5% positive predictive value and 74.0% negative predictive value. Cardiothoracic ratio as determined by chest radiograph is sensitive but not specific for identifying left ventricular dilation. Cardiothoracic ratio also has a strong negative predictive value for identifying left ventricular dilation.

Dilatancy induced ductile-brittle transition of shear band in metallic glasses.

PubMed

Zeng, F; Jiang, M Q; Dai, L H

2018-04-01

Dilatancy-generated structural disordering, an inherent feature of metallic glasses (MGs), has been widely accepted as the physical mechanism for the primary origin and structural evolution of shear banding, as well as the resultant shear failure. However, it remains a great challenge to determine, to what degree of dilatation, a shear banding will evolve into a runaway shear failure. In this work, using in situ acoustic emission monitoring, we probe the dilatancy evolution at the different stages of individual shear band in MGs that underwent severely plastic deformation by the controlled cutting technology. A scaling law is revealed that the dilatancy in a shear band is linearly related to its evolution degree. A transition from ductile-to-brittle shear bands is observed, where the formers dominate stable serrated flow, and the latter lead to a runaway instability (catastrophe failure) of serrated flow. To uncover the underlying mechanics, we develop a theoretical model of shear-band evolution dynamics taking into account an atomic-scale deformation process. Our theoretical results agree with the experimental observations, and demonstrate that the atomic-scale volume expansion arises from an intrinsic shear-band evolution dynamics. Importantly, the onset of the ductile-brittle transition of shear banding is controlled by a critical dilatation.

Dilatancy induced ductile-brittle transition of shear band in metallic glasses

NASA Astrophysics Data System (ADS)

Zeng, F.; Jiang, M. Q.; Dai, L. H.

2018-04-01

Dilatancy-generated structural disordering, an inherent feature of metallic glasses (MGs), has been widely accepted as the physical mechanism for the primary origin and structural evolution of shear banding, as well as the resultant shear failure. However, it remains a great challenge to determine, to what degree of dilatation, a shear banding will evolve into a runaway shear failure. In this work, using in situ acoustic emission monitoring, we probe the dilatancy evolution at the different stages of individual shear band in MGs that underwent severely plastic deformation by the controlled cutting technology. A scaling law is revealed that the dilatancy in a shear band is linearly related to its evolution degree. A transition from ductile-to-brittle shear bands is observed, where the formers dominate stable serrated flow, and the latter lead to a runaway instability (catastrophe failure) of serrated flow. To uncover the underlying mechanics, we develop a theoretical model of shear-band evolution dynamics taking into account an atomic-scale deformation process. Our theoretical results agree with the experimental observations, and demonstrate that the atomic-scale volume expansion arises from an intrinsic shear-band evolution dynamics. Importantly, the onset of the ductile-brittle transition of shear banding is controlled by a critical dilatation.

The narcoleptic cognitive pupillary response.

PubMed

O'Neill, W D; Trick, K P

2001-09-01

It has been reported that narcoleptics exhibit deficits in short-term memory, list recall, and stimulus frequency estimation compared with control subjects. It is also well-known that pupil dilation during cognitive tasks is a measure of subject attention state. Here we present results from six narcoleptics and six controls, a total of 360 experimental records in which pupillograms were made during cognitive tests, which indicate that narcoleptics begin pupillary dilations at a smaller diameter, begin dilating earlier poststimulus, attain higher pupillary diameter velocities, yet achieve the same equilibrium dilation diameter as controls. These findings are derived from statistical tests performed on the parameters of a nonlinear regression model of pupillary cognitive dilation as a function of time. In our experiments, the standard 1-s interdigit time between cognitive stimuli was increased to 2.3 s, which yielded pupillographic time records showing that the process of short-term memory overload sets in gradually at about four memory digits for controls and three memory digits for narcoleptics. We suggest our results can be partially explained by a narcoleptic stimulus-encoding deficit, which limits the time available for subjects to rehearse cognitive tasks. However, we also report the unexpected finding that the inferred encoding deficit is a transient one in that repeated tasks at the same memory load elicit a near normal naroleptic pupillary dilation.

Treatment of severe peptic esophageal stricture with Roux-en-Y partial gastrectomy, vagotomy, and endoscopic dilation. A follow-up study.

PubMed

Salo, J A; Ala-Kulju, K V; Heikkinen, L O; Kivilaakso, E O

1991-04-01

Eleven patients with dysphagia caused by severe esophageal stricture (length 2 to 10 cm) resulting from reflux esophagitis were treated with fibroendoscopic dilation (Eder-Puestow) and Roux-en-Y partial gastrectomy with vagotomy during 10 years (1979 to 1988). There was no operative mortality, but complications developed in three patients: One patient had a mediastinal abscess demanding thoracotomy as a result of esophageal perforation after dilatation; one had postoperative pneumonia; and one patient had ileus. After a mean follow-up of 4 years (range 1 to 10 years) esophagitis healed in all cases, as judged by endoscopy. Eight patients were asymptomatic, but three had slight transient dysphagia. Postoperatively one to eight dilations (average three to four) were needed to relieve dysphagia in the first postoperative year, but later the stricture healed in every case. Postoperative pH measurement was performed in six latest patients and showed complete absence of reflux in all cases. It is concluded that Roux-en-Y partial gastrectomy with vagotomy and endoscopic dilation is an effective, simple, and safe procedure in the management of severe peptic esophageal (acid or alkaline esophagitis) stricture. However, occasional postoperative dilations at the outpatient clinic are often needed in severe cases in the first postoperative year.

Acute stent recoil and optimal balloon inflation strategy: an experimental study using real-time optical coherence tomography.

PubMed

Kitahara, Hideki; Waseda, Katsuhisa; Yamada, Ryotaro; Otagiri, Kyuhachi; Tanaka, Shigemitsu; Kobayashi, Yuhei; Okada, Kozo; Kume, Teruyoshi; Nakagawa, Kaori; Teramoto, Tomohiko; Ikeno, Fumiaki; Yock, Paul G; Fitzgerald, Peter J; Honda, Yasuhiro

2016-06-12

Our aim was to evaluate stent expansion and acute recoil at deployment and post-dilatation, and the impact of post-dilatation strategies on final stent dimensions. Optical coherence tomography (OCT) was performed on eight bare metal platforms of drug-eluting stents (3.0 mm diameter, n=6 for each) during and after balloon inflation in a silicone mock vessel. After nominal-pressure deployment, a single long (30 sec) vs. multiple short (10 sec x3) post-dilatations were performed using a non-compliant balloon (3.25 mm, 20 atm). Stent areas during deployment with original delivery systems were smaller in stainless steel stents than in cobalt-chromium and platinum-chromium stents (p<0.001), whereas subsequent acute recoil was comparable among the three materials. At post-dilatation, acute recoil was greater in cobalt-chromium and platinum-chromium stents than in stainless steel stents (p<0.001), resulting in smaller final stent areas in cobalt-chromium and platinum-chromium stents than in stainless steel stents (p<0.001). In comparison between conventional and latest-generation cobalt-chromium stents, stent areas were not significantly different after both deployment and post-dilatation. With multiple short post-dilatations, acute recoil was significantly improved from first to third short inflation (p<0.001), achieving larger final area than a single long inflation, despite stent materials/designs (p<0.001). Real-time OCT revealed significant acute recoil in all stent types. Both stent materials/designs and post-dilatation strategies showed a significant impact on final stent expansion.

Shape of the dilated aorta in children with bicuspid aortic valve

PubMed Central

Mart, Christopher R; McNerny, Bryn E

2013-01-01

Background: The dilated aorta in adults with bicuspid aortic valve has been shown to have different shapes, but it is not known if this occurs in children. This observational study was performed to determine if there are different shapes of the dilated aorta in children with bicuspid aortic valve and their association with age, gender, hemodynamic alterations, and degree of aortic enlargement. Methods: One hundred and eighty-seven echocardiograms done on pediatric patients (0 – 18 years) for bicuspid aortic valve, during 2008, were reviewed. Aortic valve morphology, shape/size of the aorta, and pertinent hemodynamic alterations were documented. Aortic dilation was felt to be present when at least one aortic segment had a z-score > 2.0; global aortic enlargement was determined by summing the aortic segment z-scores. The aortic shape was assessed by age, gender, valve morphology, and hemodynamic alterations. Results: Aortic dilation was present in 104/187 patients. The aorta had six different shapes designated from S1 through S6. There was no association between the aortic shape and gender, aortic valve morphology, or hemodynamic abnormalities. S3 was the most common after the age of six years and was associated with the most significant degree of global aortic enlargement. Conclusions: The shape of the dilated aorta in children with bicuspid aortic valve does not occur in a uniform manner and multiple shapes are seen. S2 and S3 are most commonly seen. As aortic dilation becomes more significant, a single shape (S3) becomes the dominant pattern. PMID:24688228

In vitro fenestration of aortic stent-grafts: implications of puncture methods for in situ fenestration durability.

PubMed

Riga, Celia V; Bicknell, Colin D; Basra, Melvinder; Hamady, Mohamad; Cheshire, Nicholas J W

2013-08-01

To investigate the quality of stent-graft fenestrations created in vitro using different needle puncture and balloon dilation angles in different commercial endografts. Fenestrations were made in a standardized fashion in 3 different endograft types: Talent monofilament twill woven polyester, Zenith multifilament tubular woven polyester, and Endofit thin-walled expanded polytetrafluoroethylene (PTFE). Punctures were made at 30°, 60°, and 90° angles using a 20-G needle and dilated using 6-mm standard and 7-mm cutting balloons; at least 6 fenestrations were made at each angle with standard balloons and at least 6 with cutting balloons. The 137 fenestrations were examined under light microscopy; quantitative and qualitative digital image analysis was performed to determine size, shape, and fenestration quality. PTFE grafts were easier to puncture/dilate, resulting in larger, elliptical fenestrations with overall better quality than the Dacron grafts; however, the puncture/dilation angle made an impact on the shape and quality of fenestrations. A significant number of fabric tears were observed in PTFE fabric at <90° puncture/dilation angles compared to Dacron grafts. In Dacron grafts, fenestration quality was significantly higher with 90° puncture/dilation angles (higher in Talent grafts). Cutting balloon use resulted in significantly more fabric tears and poor quality fenestrations in all graft types. Different endografts behave significantly differently when fenestrations are fashioned. Optimum puncture/dilation is important when considering in vivo fenestration techniques. Improvements in instrumentation, materials, and techniques are required to make this a reliable and reproducible endovascular option.

Laparoscopic Heller Myotomy for Non-Dilated Esophageal Achalasia in Children with Intraoperative Stepped Dilation Under Image Guidance: Attempting Complete Myotomy.

PubMed

Miyano, Go; Miyake, Hiromu; Koyama, Mariko; Morita, Keiichi; Kaneshiro, Masakatsu; Nouso, Hiroshi; Yamoto, Masaya; Fukumoto, Koji; Urushihara, Naoto

2016-05-01

This study presents a modified surgical approach to laparoscopic myotomy for achalasia using stepped dilation with a Rigiflex balloon and contrast medium under image guidance. A 10-year-old boy with persistent dysphagia and vomiting had ingested only liquids for 3 months, losing >10 kg in body weight. Barium swallow and esophageal manometry diagnosed esophageal achalasia with mild esophageal dilatation. After failed pneumatic dilatation, laparoscopic Heller myotomy with Dor fundoplication was performed. Prior to surgery, a Rigiflex balloon dilator was placed within the esophagus near the diaphragmatic hiatus. A four-port technique was used, and mobilization of the esophagus was limited to the anterior aspect. A 5-cm Heller myotomy was performed, extending another 2 cm onto the anterior gastric wall. During myotomy, the Rigiflex balloon was serially dilated from 30 to 50 mL, and filled with contrast medium under fluoroscopic image guidance in order to maintain appropriate tension on the esophagus to facilitate myotomy, and to confirm adequate myotomy with sufficient release of lower esophageal sphincter by resecting residual circular muscle fibers. Residual circular muscle fibers can be simultaneously visualized under both fluoroscopic image guidance and direct observation through the laparoscope, and they were cut precisely until the residual notch fully disappeared. Dor fundoplication was completed. The operative time was 180 minutes, and oral intake was started after esophagography on postoperative day 1. As of the 12-month follow-up, the patient has not shown any symptoms, and his postoperative course appeared satisfactory.

Ultrasonography-guided percutaneous nephrolithotomy with Chinese one-shot tract dilation technique based on stimulated diuresis: A report of 67 cases.

PubMed

Shi, Ying; Liang, Hua-Geng; Yang, Xiong; Hai, Bo; Wang, Liang; Xing, Yi-Fei; Ju, Wen; Zeng, Fu-Qing; Zhang, Xiao-Ping; Li, Wen-Cheng

2016-12-01

The safety and effectiveness of a novel Chinese one-shot dilation technique based on stimulated diuresis for percutaneous nephrolithotomy (PCNL) were investigated. After the feasibility of the Chinese one-shot dilation based on stimulated diuresis was verified by an animal study, this technique was applied in the clinical practice. A total of 67 patients in our department underwent the modified PCNL from July 2014 to June 2015. After the renal infundibulum was distended by stimulated diuresis, the kidney was punctured under the ultrasonographic guidance via the fornix of the target calyx. The working channel was dilated using a special designed pencil-shaped fascial dilator. The successful access rate, nephrostomy tract creation time, pre- and postoperative hemoglobin values and serum creatinine concentrations, stone-free rate and complications were recorded and analyzed. The renal infundibulum was successfully distended in all of the patients by the diuresis treatment. Under the ultrasonographic guidance, the successful access rate was 100% and the mean tract creation time was 2.0 min (range: 1.5-5.0 min). The stone-free rate right after surgery was 91.0%. Although the postoperative hemoglobin was significantly reduced (P<0.01), transfusion was not clinically necessary. There was no significant difference in serum creatinine concentrations before and after operation (P>0.05). No severe complication occurred during or after the PCNL. It was suggested that this Chinese one-shot dilation technique based on stimulated diuresis is an efficient and safe innovation for PCNL, and is even helpful for those patients with non-dilated pelvicaliceal systems.

Combined antegrade and retrograde esophageal dilation for head and neck cancer-related complete esophageal stenosis.

PubMed

Goguen, Laura A; Norris, Charles M; Jaklitsch, Michael T; Sullivan, Christopher A; Posner, Marshall R; Haddad, Robert I; Tishler, Roy B; Burke, Elaine; Annino, Donald J

2010-02-01

Assess the safety and efficacy of combined antegrade and retrograde esophageal dilation (CARD) for complete esophageal stenosis following head and neck cancer (HNC) treatment. Review HNC dysphagia management. Retrospective review of all patients undergoing CARD following HNC treatment between May 2001 and September 2008. Forty-five patients were identified for review. Parameters assessed included: ability to obtain intraoperative esophageal patency, complications, number of dilations required, diet, and gastric tube (GT) status. Factors associated with dilation failure were analyzed. Intraoperative esophageal patency was obtained in 91% of patients. Median number of all dilations per patient was three. Median number of CARDs per patient was one. Resumption of oral intake occurred in 36/45 (80%). Diet results included: regular or soft diet 32/45 (71%), GT removal 27/45 (60%), and GT dependence with nothing by mouth 9/45 (20%). Laryngeal and pharyngeal stenosis, radionecrosis, tracheotomy dependence, and elongated stenosis were associated with dilation failure. Complications occurred in 18/63 (29%) CARD procedures: eight pneumomediastinum, seven GT site problems, two esophageal perforations, and one pharyngeal infection. All complications resolved spontaneously or with minimal interventions. CARD was safe and effective. Intraoperative patency was achieved in 91% of patients. Eighty percent resumed oral intake. The majority of patients had their GTs removed and resumed a soft or regular diet. Dilation failure was associated with laryngeal, pharyngeal, and excessively long esophageal stenosis, often resulting from radionecrosis. Complications were minor. CARD should be considered before relegating patients with complete esophageal stenosis to chronic GT dependence or subjecting them to laryngopharyngo esophagectomy.

Providers' Experiences with Vaginal Dilator Training for Patients with Vaginal Agenesis.

PubMed

Patel, Vrunda; Hakim, Julie; Gomez-Lobo, Veronica; Amies Oelschlager, Anne-Marie

2018-02-01

To examine providers' experiences with vaginal dilator training for patients with vaginal agenesis. Anonymous electronic survey. Members of the North American Society for Pediatric and Adolescent Gynecology. How providers learn about vaginal dilator training, common techniques, and methods used for patient training, assessment of patient readiness, common patient complaints, issues leading to early discontinuation. There were a total of 55 completed survey responses of which 31 respondents (56%) had been in practice for more than 10 years. Forty-nine were gynecologists (89%), 20 had completed a fellowship in pediatric and adolescent gynecology (36%), and 6 were reproductive endocrinologists (11%). Thirty-one respondents had first learned about vaginal dilator training through lectures (56%) whereas only 9 through mentorship and fellowship (16%). According to respondents, the most common issue leading to early discontinuation was lack of patient motivation and readiness (n = 42; 76%). The most common complication was pain or discomfort (n = 45; 82%). More than half of respondents determined dilator therapy was successful when patients reported comfortable sexual intercourse (n = 30; 55%) and 65% (n = 35) did not delineate any restrictions to initiation of sexual intercourse. Most respondents (87%) requested further vaginal dilator training at either a clinical meeting (n = 26; 47%) or with a training video (n = 22; 40%). Our study in an experienced cohort of pediatric gynecology providers highlights the need for further research and training on vaginal dilation education. Copyright © 2017 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Anal self-massage in the treatment of acute anal fissure: a randomized prospective study.

PubMed

Gaj, Fabio; Biviano, Ivano; Candeloro, Laura; Andreuccetti, Jacopo

2017-01-01

An anal fissure (AF) is a tear in the epithelial lining of the anal canal. This is a very common condition, but the choice of treatment is unclear. The use of anal dilators is effective, economic, and safe. The aim of the study was to compare the efficacy of two conservative treatments, the use of anal dilators or a finger for anal dilatation, in reducing anal pressure and resolving anal fissures. Fifty patients with a clinical diagnosis of AF were randomly assigned to one of the treatments, self-massage of the anal sphincter (group A, 25 patients) or passive dilatation using dilators (group B, 25 patients). All patients were evaluated at baseline, at the end of treatment, and after 12 weeks and 6 months. Pain was measured using a visual analog scale. After the treatment, 60% of patients treated with dilators and 80% of patients treated with anal self-massage using a finger showed disappearance of their anal fissures. A comparison between signs and symptoms reported by the patients in the two groups showed a statistically significant reduction in anal pain (group A, P=0.0001; group B, P=0.0001) and bleeding after defecation (group A, P=0.001, group B, P=0.001). At 6 months after treatment, a significantly greater reduction in anal pain was observed in Group A compared to Group B (P=0.02). The use of anal self-massage with a finger appears to induce a better resolution of acute anal fissure than do anal dilators, and in a shorter time.

Importance of early diagnosis of pancreaticobiliary maljunction without biliary dilatation

PubMed Central

Takuma, Kensuke; Kamisawa, Terumi; Tabata, Taku; Hara, Seiichi; Kuruma, Sawako; Inaba, Yoshihiko; Kurata, Masanao; Honda, Goro; Tsuruta, Koji; Horiguchi, Shin-ichiro; Igarashi, Yoshinori

2012-01-01

AIM: To clarify the strategy for early diagnosis of pancreaticobiliary maljunction (PBM) without biliary dilatation and to pathologically examine gallbladder before cancer develops. METHODS: The anatomy of the union of the pancreatic and bile ducts was assessed by using endoscopic retrograde cholangiopancreatography (ERCP). Patients with a long common channel in which communication between the pancreatic and bile ducts was maintained even during sphincter contraction were diagnosed as having PBM. Of these, patients in which the maximal diameter of the bile duct was less than 10 mm were diagnosed with PBM without biliary dilatation. The process of diagnosing 54 patients with PBM without biliary dilatation was retrospectively investigated. Histopathological analysis of resected gallbladder specimens from 8 patients with PBM without biliary dilatation or cancer was conducted. RESULTS: Thirty-six PBM patients without biliary dilatation were diagnosed with gallbladder cancer after showing clinical symptoms such as abdominal or back pain (n = 16) or jaundice (n = 12). Radical surgery for gallbladder cancer was only possible in 11 patients (31%) and only 4 patients (11%) survived for 5 years. Eight patients were suspected as having PBM without biliary dilatation from the finding of gallbladder wall thickening on ultrasound and the diagnosis was confirmed by ERCP and/or magnetic resonance cholangiopancreatography (MRCP). The median age of these 8 patients was younger by a decade than PBM patients with gallbladder cancer. All 8 patients underwent prophylactic cholecystectomy and bile duct cancer has not occurred. Wall thickness and mucosal height of the 8 resected gallbladders were significantly greater than controls, and hyperplastic changes, hypertrophic muscular layer, subserosal fibrosis, and adenomyomatosis were detected in 7 (88%), 5 (63%), 7 (88%) and 5 (63%) patients, respectively. Ki-67 labeling index was high and K-ras mutation was detected in 3 of 6 patients. CONCLUSION: To detect PBM without biliary dilatation before onset of gallbladder cancer, we should perform MRCP for individuals showing increased gallbladder wall thickness on ultrasound. PMID:22807610

Measurement of the Surface Dilatational Viscosity of an Insoluble Surfactant Monolayer at the Air/Water Interface Using a Pendant Drop Apparatus

NASA Technical Reports Server (NTRS)

Lorenzo, Jose; Couzis, Alex; Maldarelli, Charles; Singh, Bhim S. (Technical Monitor)

2000-01-01

When a fluid interface with surfactants is at rest, the interfacial stress is isotropic (as given by the equilibrium interfacial tension), and is described by the equation of state which relates the surface tension to the surfactant surface concentration. When surfactants are subjected to shear and dilatational flows, flow induced interaction of the surfactants; can create interfacial stresses apart from the equilibrium surface tension. The simplest relationship between surface strain rate and surface stress is the Boussinesq-Scriven constitutive equation completely characterized by three coefficients: equilibrium interfacial tension, surface shear viscosity, and surface dilatational viscosity Equilibrium interfacial tension and surface shear viscosity measurements are very well established. On the other hand, surface dilatational viscosity measurements are difficult because a flow which change the surface area also changes the surfactant surface concentration creating changes in the equilibrium interfacial tension that must be also taken into account. Surface dilatational viscosity measurements of existing techniques differ by five orders of magnitude and use spatially damped surface waves and rapidly expanding bubbles. In this presentation we introduce a new technique for measuring the surface dilatational viscosity by contracting an aqueous pendant drop attached to a needle tip and having and insoluble surfactant monolayer at the air-water interface. The isotropic total tension on the surface consists of the equilibrium surface tension and the tension due to the dilation. Compression rates are undertaken slow enough so that bulk hydrodynamic stresses are small compared to the surface tension force. Under these conditions we show that the total tension is uniform along the surface and that the Young-Laplace equation governs the drop shape with the equilibrium surface tension replaced by the constant surface isotropic stress. We illustrate this technique using DPPC as the insoluble surfacant monolayer and measured for it a surface dilatational viscosity in the LE phase that is 20 surface poise.

Contribution of KV1.5 Channel to H2O2-Induced Human Arteriolar Dilation and its Modulation by Coronary Artery Disease

PubMed Central

Nishijima, Yoshinori; Cao, Sheng; Chabowski, Dawid S.; Korishettar, Ankush; Ge, Alyce; Zheng, Xiaodong; Sparapani, Rodney; Gutterman, David D.; Zhang, David X.

2016-01-01

Rationale Hydrogen peroxide (H2O2) regulates vascular tone in the human microcirculation under physiological and pathophysiological conditions. It dilates arterioles by activating BKCa channels in subjects with coronary artery disease (CAD), but its mechanisms of action in subjects without CAD (non-CAD) as compared to those with CAD remain unknown. Objective We hypothesize that H2O2-elicited dilation involves different K+ channels in non-CAD versus CAD, resulting in an altered capacity for vasodilation during disease. Methods and Results H2O2 induced endothelium-independent vasodilation in non-CAD adipose arterioles, which was reduced by paxilline, a BKCa channel blocker, and by 4-AP, a KV channel blocker. Assays of mRNA transcripts, protein expression and subcellular localization revealed that KV1.5 is the major KV1 channel expressed in vascular smooth muscle cells (VSMCs) and is abundantly localized on the plasma membrane. The selective KV1.5 blocker DPO-1 and the KV1.3/1.5 blocker Psora-4 reduced H2O2-elicited dilation to a similar extent as 4-AP, but the selective KV1.3 blocker PAP-1 was without effect. In arterioles from CAD subjects, H2O2-induced dilation was significantly reduced and this dilation was inhibited by paxilline but not by 4-AP, DPO-1 or Psora-4. KV1.5 cell membrane localization and DPO-1-sensitive K+ currents were markedly reduced in isolated VSMCs from CAD arterioles, although mRNA or total cellular protein expression were largely unchanged. Conclusions In human arterioles, H2O2-induced dilation is impaired in CAD, which is associated with a transition from a combined BKCa- and KV (KV1.5)-mediated vasodilation toward a BKCa-predominant mechanism of dilation. Loss of KV1.5 vasomotor function may play an important role in microvascular dysfunction in CAD or other vascular diseases. PMID:27872049

Increased Angiotensin II Sensitivity Contributes to Microvascular Dysfunction in Women Who Have Had Preeclampsia.

PubMed

Stanhewicz, Anna E; Jandu, Sandeep; Santhanam, Lakshmi; Alexander, Lacy M

2017-08-01

Women who have had preeclampsia have increased cardiovascular disease risk; however, the mechanism(s) responsible for this association remain unclear. Microvascular damage sustained during a preeclamptic pregnancy may persist postpartum. The putative mechanisms mediating this dysfunction include a reduction in NO-dependent dilation and an increased sensitivity to angiotensin II. In this study, we evaluated endothelium-dependent dilation, angiotensin II sensitivity, and the therapeutic effect of angiotensin II receptor blockade (losartan) on endothelium-dependent dilation in vivo in the microvasculature of women with a history of preeclampsia (n=12) and control women who had a healthy pregnancy (n=12). We hypothesized that preeclampsia would have (1) reduced endothelium-dependent dilation, (2) reduced NO-mediated dilation, and (3) increased sensitivity to angiotensin II. We further hypothesized that localized losartan would increase endothelium-dependent vasodilation in preeclampsia. We assessed microvascular endothelium-dependent vasodilator function by measurement of cutaneous vascular conductance responses to graded infusion of acetylcholine (acetylcholine; 10 -7 -102 mmol/L) and a standardized local heating protocol in control sites and sites treated with 15 mmol/L L-NAME ( N G -nitro-l-arginine methyl ester; NO-synthase inhibitor) or 43 µmol/L losartan. Further, we assessed microvascular vasoconstrictor sensitivity to angiotensin II (10 -20 -10 -4 mol/L). Preeclampsia had significantly reduced endothelium-dependent dilation (-0.3±0.5 versus -1.0±0.4 log EC50 ; P <0.001) and NO-dependent dilation (16±3% versus 39±6%; P =0.006). Preeclampsia also had augmented vasoconstrictor sensitivity to angiotensin II (-10.2±1.3 versus -8.3±0.5; P =0.006). Angiotensin II type I receptor inhibition augmented endothelium-dependent vasodilation and NO-dependent dilation in preeclampsia but had no effect in healthy pregnancy. These data suggest that women who have had preeclampsia have persistent microvascular dysfunction postpartum, mediated, in part, by increased sensitivity to angiotensin II. © 2017 American Heart Association, Inc.

Slip and Dilation Tendency Anlysis of Neal Hot Springs Geothermal Area

DOE Data Explorer

Faulds, James E.

2013-12-31

Slip and Dilation Tendency in focus areas Critically stressed fault segments have a relatively high likelihood of acting as fluid flow conduits (Sibson, 1994). As such, the tendency of a fault segment to slip (slip tendency; Ts; Morris et al., 1996) or to dilate (dilation tendency; Td; Ferrill et al., 1999) provides an indication of which faults or fault segments within a geothermal system are critically stressed and therefore likely to transmit geothermal fluids. The slip tendency of a surface is defined by the ratio of shear stress to normal stress on that surface: Ts = τ / σn (Morris et al., 1996). Dilation tendency is defined by the stress acting normal to a given surface: Td = (σ1-σn) / (σ1-σ3) (Ferrill et al., 1999). Slip and dilation were calculated using 3DStress (Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by ambient stress conditions. Values range from a maximum of 1, a fault plane ideally oriented to slip or dilate under ambient stress conditions to zero, a fault plane with no potential to slip or dilate. Slip and dilation tendency values were calculated for each fault in the focus study areas at, McGinness Hills, Neal Hot Springs, Patua, Salt Wells, San Emidio, and Tuscarora on fault traces. As dip is not well constrained or unknown for many faults mapped in within these we made these calculations using the dip for each fault that would yield the maximum slip tendency or dilation tendency. As such, these results should be viewed as maximum tendency of each fault to slip or dilate. The resulting along-fault and fault-to-fault variation in slip or dilation potential is a proxy for along fault and fault-to-fault variation in fluid flow conduit potential. Stress Magnitudes and directions Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes, 2010; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012; Moeck et al., 2010; Moos and Ronne, 2010 and Reinecker et al., 2005) as well as local stress information if applicable. For faults within these focus systems we applied either a normal faulting stress regime where the vertical stress (sv) is larger than the maximum horizontal stress (shmax) which is larger than the minimum horizontal stress (sv>shmax>shmin) or strike-slip faulting stress regime where the maximum horizontal stress (shmax) is larger than the vertical stress (sv) which is larger than the minimum horizontal stress (shmax >sv>shmin) depending on the general tectonic province of the system. Based on visual inspection of the limited stress magnitude data in the Great Basin we used magnitudes such that shmin/shmax = .527 and shmin/sv= .46, which are consistent with complete and partial stress field determinations from Desert Peak, Coso, the Fallon area and Dixie valley (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes, 2011; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012). Based on inversion of fault kinematic data, Edwards (2013) interpreted that two discrete stress orientations are preserved at Neal Hot Springs. An older episode of east-west directed extension and a younger episode of southwest-northeast directed sinistral, oblique -normal extension. This interpretation is consistent with the evolution of Cenozoic tectonics in the region (Edwards, 2013). As such we applied a southwest-northeast (060) directed normal faulting stress regime, consistent with the younger extensional episode, to the Neal Hot Springs faults. Under these stress conditions northeast striking steeply dipping fault segments have the highest tendency to dilate and northeast striking 60° dipping fault segments have the highest tendency to slip. Under these stress condition...

Slip and Dilation Tendency Analysis of the Tuscarora Geothermal Area

DOE Data Explorer

Faulds, James E.

2013-12-31

Critically stressed fault segments have a relatively high likelihood of acting as fluid flow conduits (Sibson, 1994). As such, the tendency of a fault segment to slip (slip tendency; Ts; Morris et al., 1996) or to dilate (dilation tendency; Td; Ferrill et al., 1999) provides an indication of which faults or fault segments within a geothermal system are critically stressed and therefore likely to transmit geothermal fluids. The slip tendency of a surface is defined by the ratio of shear stress to normal stress on that surface: Ts = τ / σn (Morris et al., 1996). Dilation tendency is defined by the stress acting normal to a given surface: Td = (σ1-σn) / (σ1-σ3) (Ferrill et al., 1999). Slip and dilation were calculated using 3DStress (Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by ambient stress conditions. Values range from a maximum of 1, a fault plane ideally oriented to slip or dilate under ambient stress conditions to zero, a fault plane with no potential to slip or dilate. Slip and dilation tendency values were calculated for each fault in the focus study areas at, McGinness Hills, Neal Hot Springs, Patua, Salt Wells, San Emidio, and Tuscarora on fault traces. As dip is not well constrained or unknown for many faults mapped in within these we made these calculations using the dip for each fault that would yield the maximum slip tendency or dilation tendency. As such, these results should be viewed as maximum tendency of each fault to slip or dilate. The resulting along-fault and fault-to-fault variation in slip or dilation potential is a proxy for along fault and fault-to-fault variation in fluid flow conduit potential. Stress Magnitudes and directions Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes, 2010; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012; Moeck et al., 2010; Moos and Ronne, 2010 and Reinecker et al., 2005) as well as local stress information if applicable. For faults within these focus systems we applied either a normal faulting stress regime where the vertical stress (sv) is larger than the maximum horizontal stress (shmax) which is larger than the minimum horizontal stress (sv>shmax>shmin) or strike-slip faulting stress regime where the maximum horizontal stress (shmax) is larger than the vertical stress (sv) which is larger than the minimum horizontal stress (shmax >sv>shmin) depending on the general tectonic province of the system. Based on visual inspection of the limited stress magnitude data in the Great Basin we used magnitudes such that shmin/shmax = .527 and shmin/sv= .46, which are consistent with complete and partial stress field determinations from Desert Peak, Coso, the Fallon area and Dixie valley (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes, 2011; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012). Slip and dilation tendency for the Tuscarora geothermal field was calculated based on the faults mapped Tuscarora area (Dering, 2013). The Tuscarora area lies in the Basin and Range Province, as such we applied a normal faulting stress regime to the Tuscarora area faults, with a minimum horizontal stress direction oriented 115, based on inspection of local and regional stress determinations, as explained above. Under these stress conditions north-northeast striking, steeply dipping fault segments have the highest dilation tendency, while north-northeast striking 60° dipping fault segments have the highest tendency to slip. Tuscarora is defined by a left-step in a major north- to-north northeast striking, west-dipping range-bounding normal fault system. Faults within the broad step define an anticlinal accommodation zone...

Receptive Vocabulary Knowledge in Low-Functioning Autism as Assessed by Eye Movements, Pupillary Dilation, and Event-Related Potentials

DTIC Science & Technology

2011-06-01

questionnaire for Asperger Syndrome and other high-functioning autism spectrum disorders in school age children. Journal of Autism & Developmental...10-1-0404 TITLE: Receptive Vocabulary Knowledge in Low-Functioning Autism as Assessed by Eye Movements, Pupillary Dilation, and Event-Related...W81XWH-10-1-0404 Receptive Vocabulary Knowledge in Low-Functioning Autism as Assessed by Eye Movements, Pupillary Dilation, and Event-Related

Receptive Vocabulary Knowledge in Low-Functioning Autism as Assessed by Eye Movements, Pupillary Dilation, and Event-Related Potentials

DTIC Science & Technology

2012-06-01

for Asperger Syndrome and other high-functioning autism spectrum disorders in school age children. Journal of Autism & Developmental Disorders, 29...Functioning Autism as Assessed by Eye Movements, Pupillary Dilation, and Event-Related Potentials PRINCIPAL INVESTIGATOR: Barry Gordon...Knowledge in Low-Functioning Autism as Assessed by Eye- Movements, Pupillary Dilation, and Event-Related Potentials 5b. GRANT NUMBER W81XWH-10-1-0404

Image compression using quad-tree coding with morphological dilation

NASA Astrophysics Data System (ADS)

Wu, Jiaji; Jiang, Weiwei; Jiao, Licheng; Wang, Lei

2007-11-01

In this paper, we propose a new algorithm which integrates morphological dilation operation to quad-tree coding, the purpose of doing this is to compensate each other's drawback by using quad-tree coding and morphological dilation operation respectively. New algorithm can not only quickly find the seed significant coefficient of dilation but also break the limit of block boundary of quad-tree coding. We also make a full use of both within-subband and cross-subband correlation to avoid the expensive cost of representing insignificant coefficients. Experimental results show that our algorithm outperforms SPECK and SPIHT. Without using any arithmetic coding, our algorithm can achieve good performance with low computational cost and it's more suitable to mobile devices or scenarios with a strict real-time requirement.

Topological Origin of the Network Dilation Anomaly in Ion-Exchanged Glasses

NASA Astrophysics Data System (ADS)

Wang, Mengyi; Smedskjaer, Morten M.; Mauro, John C.; Sant, Gaurav; Bauchy, Mathieu

2017-11-01

Ion exchange is commonly used to strengthen oxide glasses. However, the resulting stuffed glasses usually do not reach the molar volume of as-melted glasses of similar composition—a phenomenon known as the network dilation anomaly. This behavior seriously limits the potential for the chemical strengthening of glasses and its origin remains one of the mysteries of glass science. Here, based on molecular dynamics simulations of sodium silicate glasses coupled with topological constraint theory, we show that the topology of the atomic network controls the extent of ion-exchange-induced dilation. We demonstrate that isostatic glasses do not show any network dilation anomaly. This is found to arise from the combined absence of floppy modes of deformation and internal eigenstress in isostatic atomic networks.

Slip and Dilation Tendency Anlysis of McGinness Hills Geothermal Area

DOE Data Explorer

Faulds, James E.

2013-12-31

Slip and Dilation Tendency in focus areas Critically stressed fault segments have a relatively high likelihood of acting as fluid flow conduits (Sibson, 1994). As such, the tendency of a fault segment to slip (slip tendency; Ts; Morris et al., 1996) or to dilate (dilation tendency; Td; Ferrill et al., 1999) provides an indication of which faults or fault segments within a geothermal system are critically stressed and therefore likely to transmit geothermal fluids. The slip tendency of a surface is defined by the ratio of shear stress to normal stress on that surface: Ts = τ / σn (Morris et al., 1996). Dilation tendency is defined by the stress acting normal to a given surface: Td = (σ1-σn) / (σ1-σ3) (Ferrill et al., 1999). Slip and dilation were calculated using 3DStress (Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by ambient stress conditions. Values range from a maximum of 1, a fault plane ideally oriented to slip or dilate under ambient stress conditions to zero, a fault plane with no potential to slip or dilate. Slip and dilation tendency values were calculated for each fault in the focus study areas at, McGinness Hills, Neal Hot Springs, Patua, Salt Wells, San Emidio, and Tuscarora on fault traces. As dip is not well constrained or unknown for many faults mapped in within these we made these calculations using the dip for each fault that would yield the maximum slip tendency or dilation tendency. As such, these results should be viewed as maximum tendency of each fault to slip or dilate. The resulting along-fault and fault-to-fault variation in slip or dilation potential is a proxy for along fault and fault-to-fault variation in fluid flow conduit potential. Stress Magnitudes and directions Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes, 2010; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012; Moeck et al., 2010; Moos and Ronne, 2010 and Reinecker et al., 2005) as well as local stress information if applicable. For faults within these focus systems we applied either a normal faulting stress regime where the vertical stress (sv) is larger than the maximum horizontal stress (shmax) which is larger than the minimum horizontal stress (sv>shmax>shmin) or strike-slip faulting stress regime where the maximum horizontal stress (shmax) is larger than the vertical stress (sv) which is larger than the minimum horizontal stress (shmax >sv>shmin) depending on the general tectonic province of the system. Based on visual inspection of the limited stress magnitude data in the Great Basin we used magnitudes such that shmin/shmax = .527 and shmin/sv= .46, which are consistent with complete and partial stress field determinations from Desert Peak, Coso, the Fallon area and Dixie valley (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes, 2011; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012). Slip and dilation tendency for the McGinness Hills geothermal field was calculated based on the faults mapped McGinness Hills area (Siler 2012, unpublished). The McGinness Hills area lies in the Basin and Range Province, as such we applied a normal faulting stress regime to the McGinness area faults, with a minimum horizontal stress direction oriented 115, based on inspection of local and regional stress determinations, as explained above. Under these stress conditions north-northeast striking, steeply dipping fault segments have the highest dilation tendency, while north-northeast striking 60° dipping fault segments have the highest tendency to slip. The McGinness Hills geothermal system is characterized by a left-step in a north-northeast striking west-dipping fault system wit...

Do joints initiate as sharp mode I fractures or finite thickness dilatancy bands? Insights from laboratory experiments and field data

NASA Astrophysics Data System (ADS)

Petit, J.; Chemenda, A. I.; Jorand, C.

2011-12-01

Terminology on fracture and discontinuities in geological objects mainly relies on distinguishing between tabular and sharp forms of deformation localization/failure structures (Aydin et al, JSG 2006; Shultz and Fossen, AAPG, 2009). On this basis joints (considered as mode I fractures) and dilation bands (very rarely observed) are distinguished among extension discontinuities. The former propagate with the separation of the fracture walls due to strong stress concentration at the fracture tips. The plumose features or hackles typical of joints (these terms cover a wide variety of diverging fractographic features) are believed to result from the fracture front breakdown due to the loading mode change (the origin of this change remains unclear). This view is called into question by recent experimental results of extension tests conducted on a synthetic physical rock analogue (granular, frictional, cohesive and dilatant) material (GRAM1) and by field observations of embryonic (not yet open) joints in highly jointed dolomicrite Chemenda et al., JGR, 2011). The initial porosity and grain size of both materials are very different, but at SEM scale, both experimental and natural unopened discontinuities reveal a comparable dilatancy (dilation) band structure with a porosity increase over a width of several grains. This suggests that the distinction between tabular and sharp is a matter of observation scale. Both axisymetric and poly-axial extension tests show that dilatancy bands form at elevated mean stress and have plumose morphology. Mode I cracking occurs only at very low mean stres and the forming fractures do not bear plumose features. Thus the absence of plumose structures can be considered as the signature of mode I fracturing. Consequently, we propose that non- plumose bearing natural joints (provided their fractography is not eroded) could originate as mode I fractures and call them "mode I joints". We call the joints formed as closed dilatancy bands propagating at relatively high pressure (depth) conditions and generating the plumose fractography "dilatancy joints". These joints obtained in poly-axial experiments can be very tight as is also often observed in nature. Joint spacing was shown to depend on the loading conditions but not on the sample thickness, which is another argument against the mode I mechanism. There are two main reasons for which the dilatancy joints were not detected previously: (1) the dilatancy band tends to open during exhumation (it is a weakness zone) leading to the separation of the two walls with destruction of the dilatancy band texture and mineral infilling; (2) if no opening occurs, as soon as the band of increased permeability is formed, diagenetic/epigenetic processes can rapidly cancel the initial structure, the trace of the band appearing at great magnification as a tiny mineralized vein. Such transformation must be very frequent in sedimentary rocks, but it can be absent when the mineral solubility is limited, as for the dolomicrite example presented.

Apport des moyens endoscopiques dans la dilatation des sténoses caustiques de l’œsophage

PubMed Central

Seydou, Togo; Abdoulaye, Ouattara Moussa; xing, Li; Zi, Sanogo Zimogo; sekou, Koumaré; Wen, Yang Shang; Ibrahim, Sankare; Sekou, Toure Cheik Ahmed; Boubacar, Maiga Ibrahim; Saye, Jacque; Jerome, Dakouo Dodino; Dantoumé, Toure Ousmane; Sadio, Yena

2016-01-01

Introduction Toutes les sténoses symptomatiques de l’œsophage peuvent être dilatées par voie endoscopique. Nous évaluons l'apport des moyens endoscopiques dans la prise en charge de la dilatation œsophagienne pour sténose caustique de l’œsophage (SCO) au Mali. Méthodes IL s'agissait d'une étude descriptive et prospective réalisée dans le service de chirurgie thoracique à l'hôpital du Mali. Au total 46 dossiers cliniques de patients on été enregistrés et subdivisés en 4 groupes en fonction de la topographie des lésions cicatricielles. Le nombre de cas d'assistance endoscopique réalisé a été déterminé afin de comprendre l'apport des moyens endoscopiques dans le succès de la dilatation des SCO. Pour les 2 différentes méthodes de dilatation utilisées, le résultat du traitement et le coût ont comparés. Résultats La FOGD a été utilisée dans 19 cas (41.30%) de dilatation avec la bougie de Savary Guillard et dans 47.82% des cas dans la dilatation de Lerut. La vidéo-laryngoscopie a été utilisé 58.69% des cas de dilatation à la bougie de Lerut. Le passage de guide métallique et / ou de fil-guide a été réalisée dans 39.13% avec la vidéo laryngoscopie et dans 58.68% avec la FOGD. Dans la comparaison des deux méthodes, il existe une différence significative dans la survenue des complications (p=0.04075), l'anesthésie générale (p=0.02287), l'accessibilité à la méthode (p=0.04805) et la mortalité (p=0.00402). Conclusion La SCO est une pathologie grave et sous évaluée au Mali. Les moyens endoscopiques contribuent considérablement au succès de la dilatation œsophagienne pour sténose caustique dans les différentes méthodes utilisées. PMID:27200129

[Pneumatic dilation in the treatment of achalasia].

PubMed

Ruiz Cuesta, Patricia; Hervás Molina, Antonio José; Jurado García, Juan; Pleguezuelo Navarro, María; García Sánchez, Valle; Casáis Juanena, Luis L; Gálvez Calderón, Carmen; Naranjo Rodríguez, Antonio

2013-10-01

Pneumatic dilation and surgical myotomy are currently the procedures of choice to treat achalasia. The selection of one or other treatment depends on the experience of each center and patient preferences. To review the experience of pneumatic dilation in patients with achalasia in our center. We included all patients with a clinical, endoscopic and manometric diagnosis compatible with achalasia who underwent pneumatic dilation in a 19-year period. All dilations were routinely performed with a Rigiflex(®) balloon, usually at pressures of 250, 250 and 300mm Hg in three inflations of one minute, each separated by one minute. The success of the dilation was assessed on the basis of the patient's symptoms, the number of sessions, the need for surgery, and the presence of complications. A total of 171 patients were included, 53.2% men and 46.8% women, with a mean age of 51.53±17.78 years (16-87 years), from June 1993 to October 2012. A 35-mm balloon was used in 157 patients, a 30-mm balloon in 9 patients and a 40-mm balloon in 7 patients. A single dilation session was required in 108 patients, two sessions were required in 56 patients, with a mean time between the first and second sessions of 25.23±43.25 months (1-215 months), and 3 sessions were required in 7 patients with a mean time between the second and third sessions of 6.86±5.33 months (1-15 months). Outcome after dilation was successful in 81% of the patients. Of the 140 responders, 121 had complete response (complete disappearance of symptoms without recurrence) and 19 partial response (initial disappearance of symptoms with subsequent reappearance). Surgery (Heller myotomy) was required in 15.8% of the patients. Perforation occurred in 4 of the 171 patients as a complication of the technique; these perforations were satisfactorily resolved, two by conservative treatment and two by surgery. There was no mortality associated with the technique or its complications. In our series, pneumatic dilation had a high success rate. In most patients, a single session was required and the complications rate was low. These results show that this technique is safe and effective in these patients, avoiding a large number of surgical interventions. Copyright © 2013 Elsevier España, S.L. and AEEH y AEG. All rights reserved.

High-fat diet-induced obesity leads to increased NO sensitivity of rat coronary arterioles: role of soluble guanylate cyclase activation.

PubMed

Jebelovszki, Eva; Kiraly, Csaba; Erdei, Nora; Feher, Attila; Pasztor, Eniko T; Rutkai, Ibolya; Forster, Tamas; Edes, Istvan; Koller, Akos; Bagi, Zsolt

2008-06-01

The impact of obesity on nitric oxide (NO)-mediated coronary microvascular responses is poorly understood. Thus NO-mediated vasomotor responses were investigated in pressurized coronary arterioles ( approximately 100 microm) isolated from lean (on normal diet) and obese (fed with 60% of saturated fat) rats. We found that dilations to acetylcholine (ACh) were not significantly different in obese and lean rats (lean, 83 +/- 4%; and obese, 85 +/- 3% at 1 microM), yet the inhibition of NO synthesis with N(omega)-nitro-l-arginine methyl ester reduced ACh-induced dilations only in vessels of lean controls. The presence of the soluble guanylate cyclase (sGC) inhibitor oxadiazolo-quinoxaline (ODQ) elicited a similar reduction in ACh-induced dilations in the two groups of vessels (lean, 60 +/- 11%; and obese, 57 +/- 3%). Dilations to NO donors, sodium nitroprusside (SNP), and diethylenetriamine (DETA)-NONOate were enhanced in coronary arterioles of obese compared with lean control rats (lean, 63 +/- 6% and 51 +/- 5%; and obese, 78 +/- 5% and 70 +/- 5%, respectively, at 1 microM), whereas dilations to 8-bromo-cGMP were not different in the two groups. In the presence of ODQ, both SNP and DETA-NONOate-induced dilations were reduced to a similar level in lean and obese rats. Moreover, SNP-stimulated cGMP immunoreactivity in coronary arterioles and also cGMP levels in carotid arteries were enhanced in obese rats, whereas the protein expression of endothelial NOS and the sGC beta1-subunit were not different in the two groups. Collectively, these findings suggest that in coronary arterioles of obese rats, the increased activity of sGC leads to an enhanced sensitivity to NO, which may contribute to the maintenance of NO-mediated dilations and coronary perfusion in obesity.

Role of procalcitonin in predicting dilating vesicoureteral reflux in young children hospitalized with a first febrile urinary tract infection.

PubMed

Sun, Hai-Lun; Wu, Kang-Hsi; Chen, Shan-Ming; Chao, Yu-Hua; Ku, Min-Sho; Hung, Tong-Wei; Liao, Pen-Fen; Lue, Ko-Huang; Sheu, Ji-Nan

2013-09-01

The aim of this article was to assess the usefulness of procalcitonin (PCT) as a marker for predicting dilating (grades III-V) vesicoureteral reflux (VUR) in young children with a first febrile urinary tract infection. Children ≤2 years of age with a first febrile urinary tract infection were prospectively evaluated. Serum samples were tested for PCT at the time of admission to a tertiary hospital. All children underwent renal ultrasonography (US), Tc-dimercaptosuccinic acid renal scan, and voiding cystourethrography. The diagnostic characteristics of PCT test for acute pyelonephritis and dilating VUR were calculated. Of 272 children analyzed (168 boys and 104 girls; median age, 5 months), 169 (62.1%) had acute pyelonephritis. There was VUR demonstrated in 97 (35.7%), including 70 (25.7%) with dilating VUR. The median PCT value was significantly higher in children with VUR than in those without (P < 0.001). Using a PCT cutoff value of ≥1.0 ng/mL, the sensitivity and negative predictive value for predicting dilating VUR were 94.3% and 95.4%, respectively, for PCT, and 97.1% and 97.8%, respectively, for the combined PCT and US studies, whereas the positive and negative likelihood ratios were 2.03 and 0.107, respectively, for PCT, and 1.72 and 0.067, respectively, for the combined studies. By multivariate analysis, high PCT values and abnormalities on US were independent predictors of dilating VUR. PCT is useful for diagnosing acute pyelonephritis and predicting dilating VUR in young children with a first febrile urinary tract infection. A voiding cystourethrography is indicated only in children with high PCT values (≥1.0 ng/mL) and/or abnormalities found on a US.

A novel semi-quantitative method for measuring tissue bleeding.

PubMed

Vukcevic, G; Volarevic, V; Raicevic, S; Tanaskovic, I; Milicic, B; Vulovic, T; Arsenijevic, S

2014-03-01

In this study, we describe a new semi-quantitative method for measuring the extent of bleeding in pathohistological tissue samples. To test our novel method, we recruited 120 female patients in their first trimester of pregnancy and divided them into three groups of 40. Group I was the control group, in which no dilation was applied. Group II was an experimental group, in which dilation was performed using classical mechanical dilators. Group III was also an experimental group, in which dilation was performed using a hydraulic dilator. Tissue samples were taken from the patients' cervical canals using a Novak's probe via energetic single-step curettage prior to any dilation in Group I and after dilation in Groups II and III. After the tissue samples were prepared, light microscopy was used to obtain microphotographs at 100x magnification. The surfaces affected by bleeding were measured in the microphotographs using the Autodesk AutoCAD 2009 program and its "polylines" function. The lines were used to mark the area around the entire sample (marked A) and to create "polyline" areas around each bleeding area on the sample (marked B). The percentage of the total area affected by bleeding was calculated using the formula: N = Bt x 100 / At where N is the percentage (%) of the tissue sample surface affected by bleeding, At (A total) is the sum of the surfaces of all of the tissue samples and Bt (B total) is the sum of all the surfaces affected by bleeding in all of the tissue samples. This novel semi-quantitative method utilizes the Autodesk AutoCAD 2009 program, which is simple to use and widely available, thereby offering a new, objective and precise approach to estimate the extent of bleeding in tissue samples.

Force Required to Cinch the Tricuspid Annulus: An Ex-Vivo Study

PubMed Central

Adkins, Amy; Aleman, Jesus; Boies, Lori; Sako, Edward; Bhattacharya, Shamik

2016-01-01

Background and aim of the study Tricuspid annuloplasty is the most preferred technique for the treatment of functional tricuspid regurgitation (FTR). However, high incidences of recurrent regurgitation and risky reoperation demands a deeper insight into the technique. The cinching force required to bring a dilated annulus back to the original size is unknown. The study aim was to quantify the cinching force in the tricuspid annulus which can contribute to the long-term durability of tricuspid annuloplasty and percutaneous device design. Methods In ten ovine hearts, a suture was anchored around the free wall of the tricuspid annulus with the free end attached to a force transducer. The force transducer was mounted on a slider system which pulled the suture at regular intervals. Closure of the tricuspid valve was achieved by pressurizing the right ventricle at 30 mmHg through the pulmonary valve. The suture was pulled to cinch the tricuspid annulus. The tricuspid annulus area was measured from images taken at each increment, and the corresponding force was recorded. The hearts were tested for three conditions: (i) non-pressurized (NP); (ii) pressurized (P; normal), and (iii) dilated-pressurized (DP; diseased). Leakage data were also collected for pressurized and dilated pressurized conditions. Annulus dilation was created by injecting phenol into the annulus. Results The maximum annulus dilation obtained was 8.82%, and the maximum cinching force was 0.38 ± 0.09 N. Leakage was increased by 81.73% from the pressurized to dilated condition. Conclusion The minimal force required to cinch a tricuspid annulus with severe FTR (23.98% dilation) can be approximated to 0.25 N. The required cinching force can play a major role in the long-term durability of the tricuspid annuloplasty. PMID:26897846

Evaluation of Urinary Tract Dilation Classification System for Grading Postnatal Hydronephrosis.

PubMed

Hodhod, Amr; Capolicchio, John-Paul; Jednak, Roman; El-Sherif, Eid; El-Doray, Abd El-Alim; El-Sherbiny, Mohamed

2016-03-01

We assessed the reliability and validity of the Urinary Tract Dilation classification system as a new grading system for postnatal hydronephrosis. We retrospectively reviewed charts of patients who presented with hydronephrosis from 2008 to 2013. We included patients diagnosed prenatally and those with hydronephrosis discovered incidentally during the first year of life. We excluded cases involving urinary tract infection, neurogenic bladder and chromosomal anomalies, those associated with extraurinary congenital malformations and those with followup of less than 24 months without resolution. Hydronephrosis was graded postnatally using the Society for Fetal Urology system, and then the management protocol was chosen. All units were regraded using the Urinary Tract Dilation classification system and compared to the Society for Fetal Urology system to assess reliability. Univariate and multivariate analyses were performed to assess the validity of the Urinary Tract Dilation classification system in predicting hydronephrosis resolution and surgical intervention. A total of 490 patients (730 renal units) were eligible to participate. The Urinary Tract Dilation classification system was reliable in the assessment of hydronephrosis (parallel forms 0.92). Hydronephrosis resolved in 357 units (49%), and 86 units (12%) were managed by surgical intervention. The remainder of renal units demonstrated stable or improved hydronephrosis. Multivariate analysis revealed that the likelihood of surgical intervention was predicted independently by Urinary Tract Dilation classification system risk group, while Society for Fetal Urology grades were predictive of likelihood of resolution. The Urinary Tract Dilation classification system is reliable for evaluation of postnatal hydronephrosis and is valid in predicting surgical intervention. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Losartan added to β-blockade therapy for aortic root dilation in Marfan syndrome: a randomized, open-label pilot study.

PubMed

Chiu, Hsin-Hui; Wu, Mei-Hwan; Wang, Jou-Kou; Lu, Chun-Wei; Chiu, Shuenn-Nan; Chen, Chun-An; Lin, Ming-Tai; Hu, Fu-Chang

2013-03-01

To assess the tolerability and efficacy of the investigational use of the angiotensin II receptor blocker losartan added to β-blockade (BB) to prevent progressive aortic root dilation in patients with Marfan syndrome (MFS). Between May 1, 2007, and September 31, 2011, 28 patients with MFS (11 males [39%]; mean ± SD age, 13.1±6.3 years) with recognized aortic root dilation (z score >2.0) and receiving BB (atenolol or propranolol) treatment were enrolled. They were randomized to receive BB (BB: 13 patients) or β-blockade and losartan (BB-L: 15 patients) for 35 months. In the BB-L group, aortic root dilation was reduced with treatment, and the annual dilation rate of the aortic root was significantly lower than that of the BB group (0.10 mm/yr vs 0.89 mm/yr; P=.02). The absolute aortic diameters at the sinus of Valsalva, annulus, and sinotubular junction showed similar trends, with a reduced rate of dilation in the BB-L group (P=.02, P=.03, and P=.03, respectively). Five patients (33%) treated with BB-L were noted to have a reduced aortic root diameter. However, the differences between the groups regarding changes in aortic stiffness and cross-sectional compliance were not statistically significant. This randomized, open-label, active controlled trial mostly based on a pediatric population demonstrated for the first time that losartan add-on BB therapy is safe and provides more effective protection to slow the progression of aortic root dilation than does BB treatment alone in patients with MFS. clinicaltrials.gov Identifier: NCT00651235. Copyright © 2013 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Autoantibodies against β1 receptor and AT1 receptor in type 2 diabetes patients with left ventricular dilatation.

PubMed

Zhao, Linshuang; Xu, Chunyan; Xu, Jinling

2014-01-01

To explore the relationship between the autoantibodies against the β1 and AT1 receptors and left ventricular dilatation in patients with type 2 diabetes (T2DM). The autoantibodies against the β1 and angiotensin II type 1 (AT1) receptors of T2DM patients with and without hypertension were screened by ELISA. Multiple logistic regression was used to analyze the risk factors for left ventricular dilatation. The reversing effect of left ventricular dilatation was evaluated after receptor blocker treatment. The positive rates of autoantibodies against the β1 and AT1 receptors (43.0 and 44.1%, respectively) in T2DM patients with hypertension were significantly higher than those in normotensive patients (16.0 and 10.4%, respectively; all p < 0.01). Furthermore, among T2DM patients with hypertension, the positive rates (61.4 and 64.9%, respectively) in patients with left ventricular dilatation were remarkably higher than those with normal left ventricular dimensions (34.4 and 36.1%, respectively; all p < 0.01). The presence of β1 receptor antibody and AT1 receptor antibody were risk factors for left ventricular dilatation (p < 0.05). The curative effect of metoprolol tartrate and valsartan in reversing left ventricular hypertrophy in the group positive for autoantibodies was much better than in the negative group. The findings show that autoantibodies against the β1 and AT1 receptors may play a role in predicting left ventricular dilatation in T2DM patients in combination with hypertension. Metoprolol tartrate and valsartan are effective and safe in the treatment of these patients. © 2014 S. Karger AG, Basel.

[Technical feasibility of the implantation of a monorail stent system into the renal arteries without pre-dilatation].

PubMed

Neumann, C; Gschwendtner, M; Karnel, F; Mair, J; Dorffner, G; Dorffner, R

2005-01-01

To evaluate the technical feasibility of the implantation of the monorail RX Herculink system into the renal arteries without pre-dilatation. Forty-two patients (mean age 71 years) from four centers with a total of 44 renal artery stenoses underwent implantation of the RX Herculink stent. The mean grade of the stenosis was 83.8 %, the mean length 7.5 mm. The stenoses were ostial in 38 cases and in immediate proximity to the ostium in 6 cases. The mean follow-up-period was 57 weeks (24 - 176 weeks). In 42 cases, the implantation was successful without pre-dilatation. In 2 cases, pre-dilatation was carried out. In none of the cases, detachment of the stent from the balloon was observed. In one stenosis with a length of 17 mm, implantation of two stents was performed. In 9 cases, post-dilatation with a larger balloon or higher balloon pressure was necessary. Residual stenoses exceeding 30 % were not observed. Two patients developed local bleeding at the puncture site. During the follow-up, restenoses were observed in 5 stents after 26 to 126 weeks, which necessitated a second intervention in 3 cases (PTA in 2 cases, re-stenting in 1 case). The primary patency rate after 6 and 12 months was 0.92 +/- 0.056 according to Kaplan-Meier, the secondary patency rate after 6 and 12 months was 1.0 +/- 0.0. Implantation of the RX Herculink stent system into the renal arteries without pre-dilatation is technically feasible and safe. Even without pre-dilatation, the stent-system can be advanced through the stenosis without detachment. The complication rate is low. Our clinical results are comparable to previous studies.

Frictional behavior of large displacement experimental faults

USGS Publications Warehouse

Beeler, N.M.; Tullis, T.E.; Blanpied, M.L.; Weeks, J.D.

1996-01-01

The coefficient of friction and velocity dependence of friction of initially bare surfaces and 1-mm-thick simulated fault gouges (400 mm at 25??C and 25 MPa normal stress. Steady state negative friction velocity dependence and a steady state fault zone microstructure are achieved after ???18 mm displacement, and an approximately constant strength is reached after a few tens of millimeters of sliding on initially bare surfaces. Simulated fault gouges show a large but systematic variation of friction, velocity dependence of friction, dilatancy, and degree of localization with displacement. At short displacement (<10 mm), simulated gouge is strong, velocity strengthening and changes in sliding velocity are accompanied by relatively large changes in dilatancy rate. With continued displacement, simulated gouges become progressively weaker and less velocity strengthening, the velocity dependence of dilatancy rate decreases, and deformation becomes localized into a narrow basal shear which at its most localized is observed to be velocity weakening. With subsequent displacement, the fault restrengthens, returns to velocity strengthening, or to velocity neutral, the velocity dependence of dilatancy rate becomes larger, and deformation becomes distributed. Correlation of friction, velocity dependence of friction and of dilatancy rate, and degree of localization at all displacements in simulated gouge suggest that all quantities are interrelated. The observations do not distinguish the independent variables but suggest that the degree of localization is controlled by the fault strength, not by the friction velocity dependence. The friction velocity dependence and velocity dependence of dilatancy rate can be used as qualitative measures of the degree of localization in simulated gouge, in agreement with previous studies. Theory equating the friction velocity dependence of simulated gouge to the sum of the friction velocity dependence of bare surfaces and the velocity dependence of dilatancy rate of simulated gouge fails to quantitatively account for the experimental observations.

Is side-viewing endoscope assisted balloon dilatation better for corrosive gastric outlet obstruction?

PubMed

Katiyar, Prashant; Nijhawan, Sandeep; Saradava, Vimal; Nagaich, Neeraj; Gupta, Gaurav; Mathur, Amit; Nepalia, Subhash

2013-11-01

Endoscopic balloon dilatation (EBD) is an effective therapy for caustic-induced gastric outlet obstruction (GOO). Gaining access to the stricture site is the most important step. It is sometimes difficult to negotiate a balloon through the stricture with a front-viewing endoscope due to deformed anatomy of stomach. To overcome this technical difficulty, a side-viewing endoscope can be used. There is limited data regarding the use of side-viewing endoscopes in EBD. We here report on the short-term efficacy and safety of EBD in caustic-induced GOO. In technically difficult cases, a side-viewing endoscope was used for EBD and its efficacy and safety were assessed. The study included 25 patients with caustic-induced GOO. Patients underwent EBD using a through-the-scope balloon. Initial balloon dilatation was performed with a front-viewing endoscope. A side-viewing endoscope was used where negotiation across the stricture failed with a front-viewing endoscope. Dilatation was started at 8 mm diameter and was performed at 1-week intervals. The end point of dilatation was 15 mm diameter. In 18 patients successful balloon dilatation was possible with a front-viewing endoscope. A side-viewing endoscope was used in six patients as negotiation across the stricture was not possible with a front-viewing endoscope. In all six patients negotiation across the stricture followed by successful dilatation was successful with a side-viewing endoscope. Of the 25 patients included in this study, 24 (96%) achieved procedural success (18 with a front-viewing endoscope and 6 with a side-viewing endoscope) in 3-9 sessions. Our results show that EBD is a safe and effective option for caustic-induced GOO and in difficult cases a side-viewing endoscope can be used to achieve technical success.

Visit-to-visit and 24-h blood pressure variability: association with endothelial and smooth muscle function in African Americans.

PubMed

Diaz, K M; Veerabhadrappa, P; Kashem, M A; Thakkar, S R; Feairheller, D L; Sturgeon, K M; Ling, C; Williamson, S T; Kretzschmar, J; Lee, H; Grimm, H; Babbitt, D M; Vin, C; Fan, X; Crabbe, D L; Brown, M D

2013-11-01

The purpose of this study was to investigate the association of visit-to-visit and 24-h blood pressure (BP) variability with markers of endothelial injury and vascular function. We recruited 72 African Americans who were non-diabetic, non-smoking and free of cardiovascular (CV) and renal disease. Office BP was measured at three visits and 24-h ambulatory BP monitoring was conducted to measure visit-to-visit and 24-h BP variability, respectively. The 5-min time-course of brachial artery flow-mediated dilation and nitroglycerin-mediated dilation were assessed as measures of endothelial and smooth muscle function. Fasted blood samples were analyzed for circulating endothelial microparticles (EMPs). Significantly lower CD31+CD42- EMPs were found in participants with high visit-to-visit systolic blood pressure (SBP) variability or high 24-h diastolic blood pressure (DBP) variability. Participants with high visit-to-visit DBP variability had significantly lower flow-mediated dilation and higher nitroglycerin-mediated dilation at multiple time-points. When analyzed as continuous variables, 24-h mean arterial pressure variability was inversely associated with CD62+ EMPs; visit-to-visit DBP variability was inversely associated with flow-mediated dilation normalized by smooth muscle function and was positively associated with nitroglycerin-mediated dilation; and 24-h DBP variability was positively associated with nitroglycerin-mediated dilation. All associations were independent of age, gender, body mass index and mean BP. In conclusion, in this cohort of African Americans visit-to-visit and 24-h BP variability were associated with measures of endothelial injury, endothelial function and smooth muscle function. These results suggest that BP variability may influence the pathogenesis of CV disease, in part, through influences on vascular health.

Balloon dilation of the cartilaginous portion of the eustachian tube: initial safety and feasibility analysis in a cadaver model.

PubMed

Poe, Dennis S; Hanna, Bassem Matta Nashed

2011-01-01

Balloon catheter dilation of diseased sinus ostia has recently demonstrated efficacy and safety in the treatment of chronic sinus disease with 2 years of follow-up. Similar to sinus surgery, initial studies of partial resection of inflamed mucosa from within the cartilaginous eustachian tube (ET) have demonstrated efficacy and safety in the treatment of medically refractory otitis media with effusion. Therefore, balloon dilation of the cartilaginous ET was investigated as a possible treatment modality for otitis media. A protocol for sinus balloon catheter dilation was evaluated in each of the cartilaginous ETs in 8 fresh human cadaver heads. Computed tomographic scans and detailed endoscopic inspections with video or photographic documentation were performed pre- and posttreatment, and gross anatomical dissections were done to analyze the effects of treatment and to look for evidence of undesired injury. Catheters successfully dilated all cartilaginous ETs without any significant injuries. There were no bony or cartilaginous fractures, and 3 specimens showed minor mucosal tears in the anterolateral or inferior walls. Volumetric measurements of the cartilaginous ET lumens showed a change from an average of 0.16 to 0.49 cm(3) (SD, 0.12), representing an average increase of 357% (range, 20-965%). Balloon catheter dilation of the nasopharyngeal orifice of the ET was shown to be feasible and without evidence of untoward injury. A significant increase in volume of the cartilaginous ET was achieved. A clinical study is now indicated to determine whether balloon dilation will demonstrate lasting benefits and safety in the treatment of otitis media. Copyright © 2011 Elsevier Inc. All rights reserved.

Endoscopic findings and treatment outcome in cases presenting with dysphagia.

PubMed

Hafeez, Muhammad; Salamat, Amjad; Saeed, Farrukh; Zafar, Hafiz; Hassan, Fayyaz; Farooq, Asif

2011-01-01

Dysphagia results from impeded transport of liquids, solids, or both from the pharynx to the stomach. Among the malignant lesions, carcinoma of oesophagus is the commonest cause. Our objective was to find out the frequency of different endoscopic lesions and outcome of the endoscopic therapeutic interventions in patients presenting with dysphagia. This descriptive study was conducted at Department of Gastroenterology, Military Hospital Rawalpindi from June 2008 to May 2009. Patients of dysphagia after their consent were interviewed about the symptoms. Relevant biochemical investigations were done. Barium swallow and upper Gastrointestinal (GI) Endoscopy were carried out. Benign strictures were dilated with Savary Gilliard Dilators. Malignant strictures were further evaluated to decide treatment plan. In patients considered to have oesophageal dysmotility, pressure manometery was done before specific therapy. Seventy nine patients were enrolled. Twenty-five had malignant strictures, out of those commonest was adenocarcinoma 14 (56%). Twenty-nine had benign strictures the commonest being Gastro-oesophageal Reflux Disease (GERD) related peptic stricture 9 (31%). Fifteen had oesophageal dysmotility, and achalasia was present in 10 out of them. After evaluation 12 out of 25 patients with malignant strictures were considered fit for surgery. Self-expanding metal stents (SEMS) were passed in 5. All benign strictures were dilated with Savary-Gillard dilators. Pneumatic balloon dilation was done in patients of achalasia. The commonest malignant lesion resulting in dysphagia was adenocarcinoma while in benign it was GERD related peptic stricture. Achalasia was most frequent in oesophageal motility disorders. Standard of treatment for early oesophageal malignancy is surgical resection. SEMS is a reliable way to allay dysphagia in inoperable cases. Savary Gillard dilatation in benign, and pneumatic balloon achalasia dilatations are effective ways of treatment.

A novel percutaneous nephrolithotomy (PCNL) set: The 'Economical One-shot PCNL Set' (Ecoset).

PubMed

Penbegul, Necmettin; Dede, Onur; Daggulli, Mansur; Hatipoglu, Namik Kemal; Bozkurt, Yasar

2017-09-01

To suggest a novel disposable percutaneous nephrolithotomy (PCNL) set that we named the ' Ec onomical O ne-shot PCNL Set ' (Ecoset), which consists of a single 30-F dilator, 30-F sheath, and 8-F polyurethane dilator, as use of a 'one-shot' dilatation technique during PCNL is becoming widespread. The medical records of 42 patients with kidney stones who had undergone 'one-shot' PCNL from February 2014 to June 2016 were retrospectively reviewed and analysed. Demographic data, as well as the stone size, radiation exposure time, operation time, hospitalisation duration, rate of treatment success and complications, were recorded. The mean (SD, range) age of the patients was 44.43 (16.54, 11-72) years. The mean (SD) stone size was 35.12 (17.53) mm. The mean (SD) operation time was 54.58 (22.24) min. The mean (SD) fluoroscopic screening time was limited to 154.72 (117.48) s. Treatment success was achieved in 32 (76%) patients. The mean (SD) hospital stay was 3.09 (0.75) days. None of the patients had any major complications. Bleeding requiring blood transfusion was required in three patients. The cost of a disposable dilatation set for a single PCNL operation with a balloon set, a standard Amplatz set, or an Ecoset is ∼$137, $120, or $27 (American dollars), respectively. The one-shot dilatation technique using the Ecoset for PCNL can be feasibly, safely, and effectively performed in almost every adult patient. The Amplatz dilator set and balloon dilator set have the disadvantage of relatively high cost, whereas the Ecoset is the cheapest 'disposable set' that can be used during PCNL surgery.

Parallel decrease in arterial distensibility and in endothelium-dependent dilatation in young women with a history of pre-eclampsia.

PubMed

Pàez, Olga; Alfie, José; Gorosito, Marta; Puleio, Pablo; de Maria, Marcelo; Prieto, Noemì; Majul, Claudio

2009-10-01

Pre-eclampsia not only complicates 5 to 8% of pregnancies but also increases the risk of maternal cardiovascular disease and mortality later in life. We analyzed three different aspects of arterial function (pulse wave velocity, augmentation index, and flow-mediated dilatation), in 55 nonpregnant, normotensive women (18-33 years old) according to their gestational history: 15 nulliparous, 20 with a previous normotensive, and 20 formerly pre-eclamptic pregnancy. Former pre-eclamptic women showed a significantly higher augmentation index and pulse wave velocity (P < 0.001 and P < 0.05, respectively) and lower flow-mediated dilatation (p = 0.01) compared to control groups. In contrast, sublingual nitroglycerine elicited a comparable vasodilatory response in the three groups. The augmentation index correlated significantly with pulse wave velocity and flow-mediated dilatation (R = 0.28 and R = -0.32, respectively, P < 0.05 for both). No significant correlations were observed between augmentation index or flow-mediated dilatation with age, body mass index (BMI), brachial blood pressure, heart rate, or metabolic parameters (plasma cholesterol, glucose, insulin, or insulin resistance). Birth weight maintained a significantly inverse correlation with the augmentation index (R = -0.51, p < 0.002) but not with flow-mediated dilatation. Our findings revealed a parallel decrease in arterial distensibility and endothelium-dependent dilatation in women with a history of pre-eclampsia compared to nulliparous women and women with a previous normal pregnancy. A high augmentation index was the most consistent alteration associated with a history of pre-eclampsia. The study supports the current view that the generalized arterial dysfunction associated with pre-eclampsia persists subclinically after delivery.

Idiopathic dilated cardiomyopathy: computerized anatomic study of relashionship between septal and free left ventricle wall.

PubMed

Juliani, Paulo Sérgio; Costa, Eder França da; Correia, Aristides Tadeu; Monteiro, Rosangela; Jatene, Fabio Biscegli

2014-01-01

A feature of dilated cardiomyopathy is the deformation of ventricular cavity, which contributes to systolic dysfunction. Few studies have evaluated this deformation bearing in mind ventricular regions and segments of the ventricle, which could reveal important details of the remodeling process, supporting a better understanding of its role in functional impairment and the development of new therapeutic strategies. To evaluate if, in basal, equatorial and apical regions, increased internal transverse perimeter of left ventricle in idiopathic dilated cardiomyopathy occurs proportionally between the septal and non-septal segment. We performed an anatomical study with 28 adult hearts from human cadavers. One group consisted of 18 hearts with idiopathic dilated cardiomyopathy and another group with 10 normal hearts. After lamination and left ventricle digital image capture, in three different regions (base, equator and apex), the transversal internal perimeter of left ventricle was divided into two segments: septal and not septal. These segments were measured by proper software. It was established an index of proportionality between these segments, called septal and non-septal segment index. Then we determined whether this index was the same in both groups. Among patients with normal hearts and idiopathic dilated cardiomyopathy, the index of proportionality between the two segments (septal and non-septal) showed no significant difference in the three regions analyzed. The comparison results of the indices NSS/SS among normal and enlarged hearts were respectively: in base 1.99 versus 1.86 (P=0.46), in equator 2.22 versus 2.18 (P=0.79) and in apex 2.96 versus 3.56 (P=0.11). In the idiopathic dilated cardiomyopathy, the transversal dilatation of left ventricular internal perimeter occurs proportionally between the segments corresponding to the septum and free wall at the basal, equatorial and apical regions of this chamber.

Characterization of muscarinic receptors mediating relaxation and contraction in the rat iris dilator muscle.

PubMed Central

Masuda, Y; Yamahara, N S; Tanaka, M; Ryang, S; Kawai, T; Imaizumi, Y; Watanabe, M

1995-01-01

1. The characteristics of muscarinic receptors mediating relaxation and/or contraction in the rat iris dilator muscle were examined. 2. Relaxation was induced in a dilator muscle by application of acetylcholine (ACh) at low doses (3 microM or less) and contraction was induced by high doses. Methacholine and carbachol also showed biphasic effects similar to those of ACh; in contrast, bethanechol, arecoline, pilocarpine and McN-A-343 induced mainly relaxation but no substantial contraction. 3. After parasympathetic denervation by ciliary ganglionectomy, the relaxant response to muscarinic agonists disappeared upon nerve stimulation. Application of McN-A-343 and pilocarpine induced only small contractions in denervated dilator muscles, indicating that these are partial agonists for contraction. 4. pA2 values of pirenzepine, methoctramine, AF-DX 116, himbacine, and 4-DAMP for antagonism to pilocarpine-induced relaxation in normal dilator muscles and those for antagonism to ACh-induced contraction in denervated dilator muscles were determined. The pA2 values for antagonism to relaxation of all these antagonists were most similar to those for M3-type muscarinic receptors. 5. Although pA2 values for contraction of these antagonists, except for methoctramine, were very close to those for relaxation, contraction was not significantly antagonized by methoctramine. Contraction might be mediated by M3-like receptors which have a very low affinity for methoctramine. 6. In conclusion, ACh-induced biphasic responses in rat iris dilator muscles were clearly distinguished from each other by specific muscarinic agonists and parasympathetic denervation, whereas muscarinic receptors could not be subclassified according to the pA2 values of 5 specific antagonists only. PMID:7539696

A quadriplegic patient's cholescintigraphic findings: delayed gallbladder visualization and common bile duct dilation.

PubMed Central

Shih, W. J.; Magoun, S.; Lu, G.

1996-01-01

A Tc-99m DISIDA cholescintigraphic study of a 37-year-old patient with a 20-year history of quadriplegia demonstrated dilation of the common bile duct and delayed gallbladder visualization. A concurrent sonographic study showed an enlarged gallbladder with stones and dilation of the common bile duct. These findings were proved by autopsy. Quadriplegia secondary to a high level of spinal cord injury may result in gallbladder dysfunction. Images Figure PMID:8776068

Diffuse diseases of the myocardium: MRI-pathologic review of cardiomyopathies with dilatation.

PubMed

Giesbrandt, Kirk J; Bolan, Candice W; Shapiro, Brian P; Edwards, William D; Mergo, Patricia J

2013-03-01

In this radiologic-pathologic review of the cardiomyopathies, we present the pertinent imaging findings of diffuse myocardial diseases that are associated with ventricular dilatation, including ischemic cardiomyopathy, nonischemic dilated cardiomyopathy, cardiac sarcoidosis, and iron overload cardiomyopathy. Correlation of the key radiologic findings with gross and microscopic pathologic features is presented, to provide the reader with a focused and in-depth review of the pathophysiology underlying each entity and the basis for the corresponding imaging characteristics.

Accuracy of early DMSA scan for VUR in young children with febrile UTI.

PubMed

Zhang, Xin; Xu, Hong; Zhou, Lijun; Cao, Qi; Shen, Qian; Sun, Li; Fang, Xiaoyan; Guo, Wei; Zhai, Yihui; Rao, Jia; Pa, Mier; Zhao, Ruifang; Bi, Yunli

2014-01-01

To evaluate the accuracy of an acute (99m)Tc-dimercaptosuccinic acid (DMSA) scan in predicting dilating vesicoureteral reflux (VUR) among young children with a febrile urinary tract infection (UTI). The medical records of children (≤ 2 years of age), presenting with febrile UTI between January 2000 and December 2011, were retrospectively reviewed. A total of 523 children were included in this study, of whom 397 children (75.9%) had abnormal DMSA results and 178 children (34.0%) were identified as VUR on micturating cystourethrography (MCU). Among all the patients, the number of children with dilating VUR was 151 (28.9%). The rate of abnormal results on DMSA for the dilating VUR group was significantly higher than the rates for the non-VUR and low-grade VUR groups (P < .01). In the <6 months age group and ≥ 6 months age group, the sensitivities of DMSA in predicting dilating VUR were 96.15% and 100.0%, respectively, the negative predictive values were 97.26% and 100.0%, respectively, and the negative likelihood ratios were 0.0911 and 0.0000, respectively. For children ≤ 2 years of age with a febrile UTI, an acute DMSA scan is valuable in the exclusion of dilating VUR. The likelihood of the presence of dilating VUR on MCU is rather low when the result of DMSA is negative. DMSA should be conducted to assess the need for an MCU.

Endoscopic Management of Idiopathic Subglottic Stenosis.

PubMed

Shabani, Sepehr; Hoffman, Matthew R; Brand, William T; Dailey, Seth H

2017-02-01

To describe a homogeneous idiopathic subglottic stenosis (ISS) population undergoing endoscopic balloon dilation and evaluate factors affecting inter-dilation interval (IDI). Retrospective review of 37 patients. Co-morbidity prevalence versus normal population was evaluated using chi-square tests. Correlations were evaluated using Pearson product moment tests. Independent samples t tests/rank sum tests assessed differences between groups of interest. All patients were female aged 45.9 ± 15.4 years at diagnosis. Four required a tracheotomy during management. Most prevalent co-morbidity was gastroesophageal reflux disease (GERD) (64.9%; P = .036). Body mass indices (BMI) at first and most recent dilation were 29.8 and 30.8 ( P = .564). Degree of stenosis before first dilation was 53 ± 14%. Patients underwent 3.8 ± 1.8 dilations (range, 1-11). Average IDI was 635 ± 615 days (range, 49-3130 days), including 556 ± 397 days for patients receiving concomitant steroid injection and 283 ± 36 for those who did not ( P = .079). Inter-dilation interval was not correlated with BMI ( r = 0.0486; P = .802) or number of co-morbidities ( r = -0.225, P = .223). Most patients with ISS can be managed endoscopically, and IDI may be increased with steroid injection. Gastroesophageal reflux disease is a common co-morbidity. Body mass index did not change over time despite potential effects on exercise tolerance; BMI did not affect IDI. Methods to determine optimal timing for next intervention are warranted.

Preservation of the bicuspid aortic valve.

PubMed

Schäfers, Hans-Joachim; Aicher, Diana; Langer, Frank; Lausberg, Henning F

2007-02-01

Bicuspid anatomy of the aortic valve is a common reason for aortic regurgitation and is associated with aortic dilatation in more than 50% of patients. We have observed different patterns of aortic dilatation and used different approaches preserving the valve. Between October 1995 and February 2006, a regurgitant bicuspid valve was repaired in 173 patients. The aorta was normal in 57 patients who underwent isolated repair. Aortic dilatation mainly above commissural level (n = 38) was treated by separate valve repair plus supracommissural aortic replacement. In 78 patients, aortic dilatation involved the root and was treated by root remodeling. Hospital mortality and perioperative morbidity were low in all three groups. Myocardial ischemia was significantly shorter in repair plus aortic replacement than remodeling (p < 0.001). Freedom from aortic regurgitation II or greater at 5 years varied between 91% and 96%. Freedom from reoperation at 5 years was 97% after remodeling, but only 53% after repair plus aortic replacement (p = 0.33). Symmetric prolapse was the most frequent cause for reoperation. The long-term stability of bicuspid aortic valve repair is excellent in the absence of aortic pathology. In the presence of aortic dilatation, root remodeling leads to equally stable valve durability. In patients with less pronounced root dilatation, separate valve repair plus aortic replacement may be a less complex alternative. Symmetric prolapse should be avoided if the ascending aorta is replaced.

Echocardiographic evaluation of diastolic parameters in dogs with dilated cardiomyopathy.

PubMed

Garncarz, M A

2007-01-01

Echocardiography is a valuable tool for the evaluation of systolic and diastolic cardiac function. A high correlation between measurements of diastolic mitral inflow parameters analyzed with Doppler echocardiography and invasive methods makes the former valuable. The aim of this study was to ascertain if significant differences occur in diastolic myocardial parameters between dogs with no heart disease and dogs with subclinical or clinical dilated cardiomyopathy. Furthermore the aim of the study was to determine whether heart failure in dilated cardiomypathy is a result of systolic dysfunction alone or both systolic and diastolic dysfunction. Eleven parameters were analyzed: E wave, E-AT, E-DT, E time, A wave, A-AT, A-DT, A time, E+A time, E/A ratio, and IVRT. The study confirmed the value of noninvasive echocardiographic assessment of diastolic function in dogs with dilated cardiomyopathy. Significant differences were found in E wave, E-AT, E time, E/A ratio and IVRT between healthy dogs and dogs with dilated cardiomyopathy. All are characterized by a significant decrease compared to healthy dogs after taking into account age and body weight except for the E/A ratio, which significantly increased in value. There were no significant changes in any of the Doppler parameters for diastolic evaluation in subclinical cases of DCM. Advanced heart failure in dilated cardiomyopathy entails systolic and diastolic dysfunction.

Pupillary Responses to Static Images of Men and Women: A Possible Measure of Sexual Interest?

PubMed

Snowden, Robert J; McKinnon, Aimee; Fitoussi, Julie; Gray, Nicola S

2017-12-08

The pupil dilates to images that are arousing. In Experiment 1, we examined if the pupil's response to brief presentations (2,000 ms) of static images could be used to identify individuals' sexual orientation. Participants were grouped according to their self-reported gender and sexual orientation (male heterosexual, N = 20; male bisexual, N = 13; male homosexual, N = 19; female heterosexual, N = 28; female bisexual, N = 21; female homosexual, N = 17). Pupil size was monitored to images of men in seminude poses, women in seminude poses, or neutral images. Every group showed the same pattern of responses, with the greatest dilation to male images, then female images, and least dilation to the neutral images. Experiment 2 used more tightly controlled stimuli and tested at two different image durations (150 and 3,000 ms). Both heterosexual men (N = 18) and women (N = 20) showed greater pupil dilation to images of nude men than to nude women. However, in Experiment 3, where we reduced the erotic content by using images of clothed models, both heterosexual men and women showed greater pupil dilation to images of women. The results showed that while the pupil does dilate strongly to sexual imagery, its response to these brief static images does not correspond to a person's sexual orientation in a simple manner.

High-resolution manometry findings in patients with achalasia and massive dilated megaesophagus.

PubMed

Menezes, M A; Andolfi, C; Herbella, F A M; Patti, M G

2017-05-01

Achalasia may present in a non-advanced or an advanced (end stage) stage based on the degree of esophageal dilatation. Manometric parameters and esophageal caliber may be prognostic for the outcome of treatment. The correlation between manometry and disease stage has not been yet fully studied. This study aims to describe high-resolution manometry findings in patients with achalasia and massive dilated megaesophagus. Eighteen patients (mean age 61 years, 55% females) with achalasia and massive dilated megaesophagus, as defined by a maximum esophageal dilatation >10 cm at the barium esophagram, were studied. Achalasia was considered secondary to Chagas' disease in 14 (78%) of the patients and idiopathic in the remaining. All patients underwent high-resolution manometry. Upper esophageal sphincter was hypotonic and had impaired relaxation in the majority of patients. Aperistalsis was seen in all patients with an equal distribution of Chicago type I and type II. No type III was noticed. Lower esophageal sphincter did not have a characteristic manometric pattern. In 50% of the cases, the manometry catheter was not able to reach the stomach. Our results did not show a manometric pattern in patients with achalasia and massive dilated esophagus. © The Authors 2017. Published by Oxford University Press on behalf of International Society for Diseases of the Esophagus. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Endoscopic balloon dilatation as an effective treatment for lower and upper benign gastrointestinal system anastomotic stenosis.

PubMed

Akarsu, Cevher; Unsal, Mustafa Gokhan; Dural, Ahmet Cem; Kones, Osman; Kocatas, Ali; Karabulut, Mehmet; Kankaya, Burak; Ates, Mustafa; Alis, Halil

2015-04-01

Endoscopic balloon dilatation (EBD) is currently accepted as an effective, safe, and first-line treatment of postoperative benign gastrointestinal anastomosis stenosis (BGAS); however, a limited number of publications on the subject exist in the literature. The aim of the study was to retrospectively evaluate the efficiency of endoscopic dilatation in patients with postoperative intestinal anastomotic stenoses at a single surgical center. Patients with postoperative BGAS treated by EBD at our institution from February 2008 to 2012 were included. The dilatations were all performed using through-the-scope balloons. The balloon was introduced into the stricture using a guidewire under radiologic guidance. Each dilatation session consisted of 2 to 3 two-minute multistep inflations of the balloon until adequate dilatation was achieved. Of the 48 patients included in the study, 44 patients (91.7%) fully recovered and 4 (8.3%) did not respond to treatment. The mean follow-up period was 24 months (range, 3 to 57 mo). Four patients who did not respond to the procedure were treated surgically. Two patients (4.1%) with intestinal perforation during EBD were treated conservatively with a stent. EBD has a low rate of complications and a high success rate, is well tolerated, and avoids further surgical procedures for BGAS. Therefore, EBD should be the first choice of treatment for postoperative anastomotic stenoses.

Treatment of multiple-level tracheobronchial stenosis secondary to endobronchial tuberculosis using bronchoscopic balloon dilatation with topical mitomycin-C.

PubMed

Faisal, Mohamed; Harun, Hafaruzi; Hassan, Tidi M; Ban, Andrea Y L; Chotirmall, Sanjay H; Abdul Rahaman, Jamalul Azizi

2016-04-14

Tracheobronchial stenosis is a known complication of endobronchial tuberculosis. Despite antituberculous and steroid therapy, the development of bronchial stenosis is usually irreversible and requires airway patency to be restored by either bronchoscopic or surgical interventions. We report the use of balloon dilatation and topical mitomycin-C to successful restore airway patency. We present a 24-year old lady with previous pulmonary tuberculosis and laryngeal tuberculosis in 2007 and 2013 respectively who presented with worsening dyspnoea and stridor. She had total left lung collapse with stenosis of both the upper trachea and left main bronchus. She underwent successful bronchoscopic balloon and manual rigid tube dilatation with topical mitomycin-C application over the stenotic tracheal segment. A second bronchoscopic intervention was performed after 20 weeks for the left main bronchus stenosis with serial balloon dilatation and topical mitomycin-C application. These interventions led to significant clinical and radiographic improvements. This case highlights that balloon dilatation and topical mitomycin-C application should be considered in selected patients with tracheobronchial stenosis following endobronchial tuberculosis, avoiding airway stenting and invasive surgical intervention.

Dilatancy of Shear Transformations in a Colloidal Glass

NASA Astrophysics Data System (ADS)

Lu, Y. Z.; Jiang, M. Q.; Lu, X.; Qin, Z. X.; Huang, Y. J.; Shen, J.

2018-01-01

Shear transformations, as fundamental rearrangement events operating in local regions, hold the key of plastic flow of amorphous solids. Despite their importance, the dynamic features of shear transformations are far from clear, which is the focus of the present study. Here, we use a colloidal glass under shear as the prototype to directly observe the shear-transformation events in real space. By tracing the colloidal-particle rearrangements, we quantitatively determine two basic properties of shear transformations: local shear strain and dilatation (or free volume). It is revealed that the local free volume undergoes a significantly temporary increase prior to shear transformations, eventually leading to a jump of local shear strain. We clearly demonstrate that shear transformations have no memory of the initial free volume of local regions. Instead, their emergence strongly depends on the dilatancy ability of these local regions, i.e., the dynamic creation of free volume. More specifically, the particles processing the high dilatancy ability directly participate in subsequent shear transformations. These results experimentally enrich Argon's statement about the dilatancy nature of shear transformations and also shed insight into the structural origin of amorphous plasticity.

Pupils dilate for vocal or familiar music.

PubMed

Weiss, Michael W; Trehub, Sandra E; Schellenberg, E Glenn; Habashi, Peter

2016-08-01

Previous research reveals that vocal melodies are remembered better than instrumental renditions. Here we explored the possibility that the voice, as a highly salient stimulus, elicits greater arousal than nonvocal stimuli, resulting in greater pupil dilation for vocal than for instrumental melodies. We also explored the possibility that pupil dilation indexes memory for melodies. We tracked pupil dilation during a single exposure to 24 unfamiliar folk melodies (half sung to la la, half piano) and during a subsequent recognition test in which the previously heard melodies were intermixed with 24 novel melodies (half sung, half piano) from the same corpus. Pupil dilation was greater for vocal melodies than for piano melodies in the exposure phase and in the test phase. It was also greater for previously heard melodies than for novel melodies. Our findings provide the first evidence that pupillometry can be used to measure recognition of stimuli that unfold over several seconds. They also provide the first evidence of enhanced arousal to vocal melodies during encoding and retrieval, thereby supporting the more general notion of the voice as a privileged signal. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Pouch dilatation following laparoscopic adjustable gastric banding: psychobehavioral factors (can psychiatrists predict pouch dilatation?).

PubMed

Poole, Norman; Al Atar, Ashraf; Bidlake, Louise; Fienness, Alberic; McCluskey, Sara; Nussey, S; Bano, Gal; Morgan, John

2004-01-01

Laparoscopic adjustable gastric banding is increasingly being performed in morbidly obese individuals for weight loss. Some patients develop pouch dilatation as a postoperative complication that limits the utility of the procedure. Surgical variables are poor predictors of this complication. 5 patients from a series of 157 who underwent LAGB at a single center developed the condition. Psychiatric and surgical case-notes were analyzed retrospectively for the presence of operationally defined psychiatric disorders and compared to 10 controls from the same population. Cases were significantly more likely to have past or current binge eating, emotionally triggered eating with reduced awareness of the link, a history of affective disorder, reduced sexual functioning and successful preoperative weight loss. No difference between groups was observed for compliance with orlistat, childhood sexual abuse, relationships with parents, history of bulimia nervosa, rate of band inflation or preoperative BMI. Psychological factors may be better predictors of pouch dilatation than biomedical variables. Disordered eating can be an attempt to modulate negative emotions. Pouch dilatation may be a consequence of this eating behavior.

Dilated cardiomyopathy

MedlinePlus

... other causes of dilated cardiomyopathy, including: Alcohol or cocaine abuse Diabetes, thyroid disease, or hepatitis Medicines that ... how much salt (sodium) you get in your diet. Most people who have heart failure need to ...

Endoscope-guided pneumatic dilation for treatment of esophageal achalasia

PubMed Central

Chuah, Seng-Kee; Wu, Keng-Liang; Hu, Tsung-Hui; Tai, Wei-Chen; Changchien, Chi-Sin

2010-01-01

Pneumatic dilation (PD) is considered to be the first line nonsurgical therapy for achalasia. The principle of the procedure is to weaken the lower esophageal sphincter by tearing its muscle fibers by generating radial force. The endoscope-guided procedure is done without fluoroscopic control. Clinicians usually use a low-compliance balloon such as Rigiflex dilator to perform endoscope-guided PD for the treatment of esophageal achalasia. It has the advantage of determining mucosal injury during the dilation process, so that a repeat endoscopy is not needed to assess the mucosal tearing. Previous studies have shown that endoscope-guided PD is an efficient and safe nonsurgical therapy with results that compare well with other treatment modalities. Although the results may be promising, long-term follow-up is required in the near future. PMID:20101764

[Tissue expansion under the cicatrix].

PubMed

Cai, Guo-Bin; Liu, Liu; Li, Tai-Ying; Zhang, Yi; Wang, Chun-Mei

2005-09-01

To investigate a more simple and effective method to repair cicatrix by tissue expansion. The dilator with the capacity of 80 - 500 ml was implanted into the subcutaneous pocket under the cicatrix. After dilating for one to two months, the dilator was taken out and the wound surface of the cicatrix was removed. The expanded skin flap was advanced or rotated to cover the defects. The procedure was used on 203 cases. The dilatation was achieved successfully in all the cases, followed by cicatrix removing and repair. The incision scar was not noticeable. Tissue expansion under the cicatrix has the advantages of safety, less trauma and less extra incisions. It is a reasonable choice to obtain more flexible surgical designs and more economical skin flap applications. It is suitable for most of the treatment for cicatrix.

Dilation and Hypertrophy: A Cell-Based Continuum Mechanics Approach Towards Ventricular Growth and Remodeling

NASA Astrophysics Data System (ADS)

Ulerich, J.; Göktepe, S.; Kuhl, E.

This manuscript presents a continuum approach towards cardiac growth and remodeling that is capable to predict chronic maladaptation of the heart in response to changes in mechanical loading. It is based on the multiplicative decomposition of the deformation gradient into and elastic and a growth part. Motivated by morphological changes in cardiomyocyte geometry, we introduce an anisotropic growth tensor that can capture both hypertrophic wall thickening and ventricular dilation within one generic concept. In agreement with clinical observations, we propose wall thickening to be a stress-driven phenomenon whereas dilation is introduced as a strain-driven process. The features of the proposed approach are illustrated in terms of the adaptation of thin heart slices and in terms overload-induced dilation in a generic bi-ventricular heart model.

An update on canine cardiomyopathies - is it all in the genes?

PubMed

Dutton, E; López-Alvarez, J

2018-04-17

Dilated cardiomyopathy is the second most common cardiac disease in dogs and causes considerable morbidity and mortality. Primary dilated cardiomyopathy is suspected to be familial, and genetic loci have been associated with the disease in a number of breeds. Because it is an adult-onset disease, usually with late onset, testing breeding dogs and bitches before breeding for a genetic mutation that could lead to dilated cardiomyopathy would be helpful to prevent disease. There is growing evidence that the genetic basis may be multigenic rather than monogenic in the majority of studied breeds. This review article describes the known genetic aspects of canine dilated cardiomyopathy and the implications of genetic tests on heart testing and the future of veterinary cardiology. © 2018 British Small Animal Veterinary Association.

Cutting balloon and high-pressure balloon dilation for palliative treatment of congenital double-chambered right ventricle and primary infundibular stenosis in a Golden retriever dog.

PubMed

Schober, Karsten E; Rhinehart, Jaylyn; Kohnken, Rebecca; Bonagura, John D

2017-12-01

Combined cutting balloon and high-pressure balloon dilation was performed in a dog with a double-chambered right ventricle and severe infundibular stenosis of the right ventricular outflow tract. The peak systolic pressure gradient across the stenosis decreased by 65% after dilation (from 187 mmHg before to 66 mmHg after) affirming the intervention as successful. However, early re-stenosis occurred within 3 months leading to exercise intolerance, exercise-induced syncope, and right-sided congestive heart failure. Cutting balloon followed by high-pressure balloon dilation provided temporary but not long-term relief of right ventricular obstruction in this dog. Copyright © 2017 Elsevier B.V. All rights reserved.

New labor management guidelines and changes in cesarean delivery patterns.

PubMed

Rosenbloom, Joshua I; Stout, Molly J; Tuuli, Methodius G; Woolfolk, Candice L; López, Julia D; Macones, George A; Cahill, Alison G

2017-12-01

In 2010 the Consortium on Safe Labor published labor curves. It was proposed that the rate of cesarean delivery could be lowered by avoiding the diagnosis of arrest of dilation before 6 cm. However, there is little information on the uptake of the guidelines and on changes in cesarean delivery rates that may have occurred. The objective of the study was to test the following hypotheses: (1) among patients laboring at term, rates of arrest of dilation disorders have decreased, leading to a decrease in the rate of cesarean delivery; (2) in the second stage, pushing duration prior to diagnosis of arrest of descent has increased, also leading to a reduction in the rate of cesarean delivery for this indication. As a secondary aim, we investigated changes in maternal and neonatal morbidity. This was a secondary analysis of a prospective cohort study of all patients presenting at ≥37 weeks' gestation from 2010 through 2014 with a nonanomalous vertex singleton and no prior history of cesarean delivery. Rates of cesarean delivery, arrest of dilation, and changes in rates of maternal and neonatal morbidity were calculated in crude and adjusted models. Cervical dilation at diagnosis of the arrest of dilation, time spent at the maximal dilation prior to diagnosis of arrest of dilation, and time in the second stage prior to the diagnosis of arrest of descent were compared over the study period. There were 7845 eligible patients. The cesarean delivery rate in 2010 was 15.8% and, in 2014, 17.7% (P trend = .51). In patients undergoing cesarean delivery for the arrest of dilation, the median cervical dilation at the time of cesarean delivery was at 5.5 cm in 2010 and 6.0 cm in 2014 (P trend = .94). In these patients, there was an increase in the time spent at last dilation: 3.8 hours in 2010 to 5.2 hours in 2014 (P trend = .02). There was no change in the frequency of patients diagnosed with the arrest of dilation at <6 cm: 51.4% in 2010 and 48.6% in 2014 (P trend = .56). However, in these patients, the median time spent at the last cervical dilation was 4.0 hours in 2010 and 6.7 hours in 2014 (P trend = .046). There were 206 cesarean deliveries for the arrest of descent. The median pushing time in these patients increased in multiparous patients from 1.1 hours in 2010 to 3.4 hours in 2014 (P trend = .009); in nulliparous patients these times were 2.7 hours in 2010 and 3.8 hours in 2014 (P trend = .09). There was a significant trend toward increasing adverse neonatal and maternal outcomes (P < .001 for each). The adjusted odds ratio for adverse maternal outcome for 2014 compared with 2010 was 1.66 (95% confidence interval, 1.27-2.17); however, considering only transfusion, hemorrhage, or infection, there was no difference (P trend = .96). The adjusted odds ratio of adverse neonatal outcome in 2014 compared with 2010 was 1.80 (95% confidence interval, 1.36-2.36). Despite significant changes in labor management that have occurred over the initial years since publication of the new labor curves and associated guidelines, the primary cesarean delivery rate was not reduced and there has been an increase in maternal and neonatal morbidity in our institution. A randomized controlled trial is needed. Copyright © 2017 Elsevier Inc. All rights reserved.

Isolated Main Pancreatic Duct Dilatation: CT Differentiation Between Benign and Malignant Causes.

PubMed

Kim, Se Woo; Kim, Se Hyung; Lee, Dong Ho; Lee, Sang Min; Kim, Yeon Soo; Jang, Jin Young; Han, Joon Koo

2017-11-01

The purpose of this study is to retrospectively evaluate the differential CT features of isolated benign and malignant main pancreatic duct (MPD) dilatation and to investigate whether the diagnostic performance of radiologists can be improved with knowledge of these differential CT features. Forty-one patients who had isolated MPD dilatation without any visible mass on CT from January 2000 to October 2016 were retrospectively enrolled in the study. Two radiologists reviewed CT images in consensus for the location, shape (smooth vs abrupt), length of transition, dilated pancreatic duct (PD) diameter, presence of duct penetrating sign, parenchymal atrophy, attenuation difference, associated pancreatitis, calcification, PD or common bile duct (CBD) enhancement, and perilesional cyst. The chi-square test, Fisher exact test, and t test were used to find the differential CT features of benign and malignant MPD dilatation. Two successive review sessions for differentiation between the two disease entities were then independently performed by three other reviewers with differing expertise, with the use of a 5-point confidence scale. The first session provided no information for differentiation; however, reviewers were aware of the results of univariate analyses in the second session. The diagnostic performance of the radiologists was evaluated using a pairwise comparison of ROC curves. A total of 19 benign and 22 malignant MPD dilatations were identified. In patients with benign MPD dilatation, transition areas were frequently located in the head (57.9% [11/19] vs 13.6% [3/22], p = 0.003) and showed significantly shorter (< 6.1 mm) (78.9% [15/19] vs 9.1% [2/22], p < 0.0001) and smooth transition (89.5% [17/19] vs 9.1% [2/22], p < 0.0001). Duct penetrating sign was exclusively observed in patients with benign MPD dilatation (73.7% [14/19] vs 0% [0/22], p < 0.0001). In contrast, malignant MPD dilatation frequently was accompanied by attenuation difference (63.6% [14/22] vs 10.5% [2/19], p = 0.001) and associated PD or CBD enhancement (36.4% [8/22] vs 0% [0/19], p = 0.003). The AUC values of three reviewers significantly increased from 0.653, 0.587, and 0.884 to 0.864, 0.964, and 0.908, respectively, with knowledge of significant CT features (p = 0.013, p < 0.0001, and p = 0.701, respectively). Distal, long (≥ 6.1 mm), and abrupt transition, the absence of duct penetrating sign, and the presence of attenuation difference and PD or CBD enhancement were highly suggestive CT findings for differentiation of malignant from benign MPD dilatation. The diagnostic performance of radiologists with regard to differentiation was significantly improved with knowledge of these highly suggestive CT criteria.

Depressed perivascular sensory innervation of mouse mesenteric arteries with advanced age.

PubMed

Boerman, Erika M; Segal, Steven S

2016-04-15

The dilatory role for sensory innervation of mesenteric arteries (MAs) is impaired in Old (∼24 months) versus Young (∼4 months) mice. We investigated the nature of this impairment in isolated pressurized MAs. With perivascular sensory nerve stimulation, dilatation and inhibition of sympathetic vasoconstriction observed in Young MAs were lost in Old MAs along with impaired dilatation to calcitonin gene-related peptide (CGRP). Inhibiting NO and prostaglandin synthesis increased CGRP EC50 in Young and Old MAs. Endothelial denudation attenuated dilatation to CGRP in Old MAs yet enhanced dilatation to CGRP in Young MAs while abolishing all dilatations to ACh. In Old MAs, sensory nerve density was reduced and RAMP1 (CGRP receptor component) associated with nuclear regions of endothelial cells in a manner not seen in Young MAs or in smooth muscle cells of either age. With advanced age, loss of dilatory signalling mediated through perivascular sensory nerves may compromise perfusion of visceral organs. Vascular dysfunction and sympathetic nerve activity increase with advancing age. In the gut, blood flow is governed by perivascular sensory and sympathetic nerves but little is known of how their functional role is affected by advanced age. We tested the hypothesis that functional sensory innervation of mesenteric arteries (MAs) is impaired for Old (24 months) versus Young (4 months) C57BL/6 male mice. In cannulated pressurized MAs preconstricted 50% with noradrenaline and treated with guanethidine (to inhibit sympathetic neurotransmission), perivascular nerve stimulation (PNS) evoked dilatation in Young but not Old MAs while dilatations to ACh were not different between age groups. In Young MAs, capsaicin (to inhibit sensory neurotransmission) blocked dilatation and increased constriction during PNS. With no difference in efficacy, the EC50 of CGRP as a vasodilator was ∼6-fold greater in Old versus Young MAs. Inhibiting nitric oxide (l-NAME) and prostaglandin (indomethacin) synthesis increased CGRP EC50 in both age groups. Endothelial denudation reduced the efficacy of dilatation to CGRP by ∼30% in Old MAs yet increased this efficacy ∼15% in Young MAs while all dilatations to ACh were abolished. Immunolabelling revealed reduced density of sensory (CGRP) but not sympathetic (tyrosine hydroxylase) innervation for Old versus Young MAs. Whereas the distribution of CGRP receptor proteins was similar in SMCs, RAMP1 associated with nuclear regions of endothelial cells of Old but not Young MAs. With advanced age, the loss of sensory nerve function and diminished effectiveness of CGRP as a vasodilator is multifaceted and may adversely affect splanchnic perfusion. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

Plummer-Vinson Syndrome with Proximal Esophageal Web.

PubMed

Changela, Kinesh; Haeri, Nami Safai; Krishnaiah, Mahesh; Reddy, Madhavi

2016-05-01

Plummer-Vinson Syndrome is a condition where iron deficiency is associated with difficulty swallowing due to the presence of an esophageal web. Deficiency of iron-dependent oxidative enzymes causes gradual degradation of the pharyngeal muscles which lead to mucosal atrophy and formation of webs. Although it is a very rare condition, an increased risk of esophageal squamous cell carcinoma makes its identification very important. Dilation of the esophageal web using a Savary dilator is a more effective and safer approach compared to conventional balloon dilation.

Vaginal Examination Simulation Using Citrus Fruit to Simulate Cervical Dilation and Effacement

PubMed Central

Shea, Kathleen L

2015-01-01

This technical report describes the creation and use of a cervical dilation and effacement model in a pre-licensure nursing course in reproductive health. Vaginal examination is typically taught in reproductive health courses; however, nursing students do not always have sufficient opportunity to practice on actual patients. This low-cost task-training model provides undergraduate nursing students the opportunity to experience performing a vaginal examination to assess for cervical dilation and effacement during the labor process. PMID:26457235

Learning about Marfan Syndrome

MedlinePlus

... threatening symptom of Marfan syndrome. They include dilated aorta just as it leaves the heart (at the ... clinical diagnostic features: Dilatation or dissection of the aorta at the level of the sinuses of Valsava. ...

Electrocautery vs non-electrocautery dilation catheters in endoscopic ultrasonography-guided pancreatic fluid collection drainage

PubMed Central

Kitamura, Katsuya; Yamamiya, Akira; Ishii, Yu; Nomoto, Tomohiro; Honma, Tadashi; Yoshida, Hitoshi

2016-01-01

AIM: To investigate the safety and utility of an electrocautery dilation catheter for endoscopic ultrasonography (EUS)-guided pancreatic fluid collection drainage. METHODS: A single-center, exploratory, retrospective study was conducted between August 2010 and August 2014. This study was approved by the Medical Ethics Committee of our institution. Informed, written consent was obtained from each patient prior to the procedure. The subjects included 28 consecutive patients who underwent EUS-guided transmural drainage (EUS-TD) for symptomatic pancreatic and peripancreatic fluid collections (PFCs) by fine needle aspiration using a 19-gauge needle. These patients were retrospectively divided into two groups based on the use of an electrocautery dilation catheter as a fistula dilation device; 15 patients were treated with an electrocautery dilation catheter (electrocautery group), and 13 patients were treated with a non-electrocautery dilation catheter (non-electrocautery group). We evaluated the technical and clinical successes and the adverse events associated with EUS-TD for the treatment of PFCs between the two groups. RESULTS: There were no significant differences in age, sex, type, location and diameter of PFCs between the groups. Thirteen patients (87%) in the electrocautery group and 10 patients (77%) in the non-electrocautery group presented with infected PFCs. The technical success rates of EUS-TD for the treatment of PFCs were 100% (15/15) and 100% (13/13) for the electrocautery and the non-electrocautery groups, respectively. The clinical success rates of EUS-TD for the treatment of PFCs were 67% (10/15) and 69% (9/13) for the electrocautery and the non-electrocautery groups, respectively (P = 0.794). The procedure time of EUS-TD for the treatment of PFCs in the electrocautery group was significantly shorter than that of the non-electrocautery group (mean ± SD: 30 ± 12 min vs 52 ± 20 min, P < 0.001). Adverse events associated with EUS-TD for the treatment of PFCs occurred in 0 patients and 1 patient for the electrocautery and the non-electrocautery groups, respectively (P = 0.942). CONCLUSION: EUS-TD using an electrocautery dilation catheter as a fistula dilation device for the treatment of symptomatic PFCs appears safe and contributes to a shorter procedure time. PMID:27433292

Primary obstructive megaureter: the role of high pressure balloon dilation.

PubMed

Romero, Rosa M; Angulo, Jose Maria; Parente, Alberto; Rivas, Susana; Tardáguila, Ana Rosa

2014-05-01

There is a growing interest in minimally invasive treatment of primary obstructive megaureter (POM) in children. The absence of long-term follow-up data, however, makes it difficult to establish the indication for an endoscopic approach. The aim of our study is to determine the long-term efficacy of endourologic high-pressure balloon dilation of the vesicoureteral junction (VUJ) in children with POM that necessitates surgical treatment. We retrospectively reviewed the clinical records from children with POM who were treated with endourologic high-pressure balloon dilation of the VUJ from March 2003 to April 2010. To determine the long-term, a cohort study was conducted in November 2011. Endourologic dilation of the VUJ was performed with a semicompliant high-pressure balloon (2.7 FG) with a minimum balloon size of 3 mm, followed by placement of a Double-J stent. We have treated 29 (32 renal units, left [n=16], right [n=10] and bilateral [n=3]) children with a diagnosis of POM within this period. The median age at the time of the endourologic treatment was 4.04 months (range 1.6-39 months). In three cases, an open ureteral reimplantation was needed, in two cases because of intraoperative technical failure and postoperative Double-J stent migration in one patient. The 26 children (29 renal units) who had a successful endourologic dilation of the VUJ were followed with ultrasonography and MAG-3-Lasix (furosemide) studies that showed a progressive improvement of both the ureterohydronephrosis and drainage in the first 18 months in 20 patients (23 renal units) (69%). In two patients who were treated with a 3 mm balloon, a further dilation was needed, with an excellent outcome. The cohort study (at a median follow-up of 47 months) showed that in all patients who had a good outcome at the 18-month follow-up after endourologic balloon dilation remained asymptomatic with resolution of ureterohydronephrosis on the US and good drainage on the renogram, in the children with some persistent hydronephrosis. Our study shows that children with POM who were treated with high-pressure ballon dilation of the VUJ who have satisfactory appearance at 18 months maintain these results over time.

Electrophysiological effects of acute atrial stretch on persistent atrial fibrillation in patients undergoing open heart surgery.

PubMed

Elvan, Arif; Adiyaman, Ahmet; Beukema, Rypko J; Sie, Hauw T; Allessie, Maurits A

2013-03-01

The electrophysiologic effects of acute atrial dilatation and dedilatation in humans with chronic atrial fibrillation remains to be elucidated. To study the electrophysiological effects of acute atrial dedilatation and subsequent dilatation in patients with long-standing persistent atrial fibrillation (AF) with structural heart disease undergoing elective cardiac surgery. Nine patients were studied. Mean age was 71 ± 10 years, and left ventricular ejection was 46% ± 6%. Patients had at least moderate mitral valve regurgitation and dilated atria. After sternotomy and during extracorporal circulation, mapping was performed on the beating heart with 2 multielectrode arrays (60 electrodes each, interelectrode distance 1.5 mm) positioned on the lateral wall of the right atrium (RA) and left atrium (LA). Atrial pressure and size were altered by modifying extracorporal circulation. AF electrograms were recorded at baseline after dedilation and after dilatation of the atria afterward. At baseline, the median AF cycle length (mAFCL) was 184 ± 27 ms in the RA and 180 ± 17 ms in the LA. After dedilatation, the mAFCL shortened significantly to 168 ± 13 ms in the RA and to 168 ± 20 ms in the LA. Dilatation lengthened mAFCL significantly to 189 ± 17 ms in the RA and to 185 ± 23 ms in the LA. Conduction block (CB) at baseline was 14.3% ± 3.6% in the RA and 17.3% ± 5.5% in the LA. CB decreased significantly with dedilatation to 7.4% ± 2.9% in the RA and to 7.9% ± 6.3% in the LA. CB increased significantly with dilatation afterward to 15.0% ± 8.3% in the RA and to 18.5% ± 16.0% in the LA. Acute dedilatation of the atria in patients with long-standing persistent AF causes a decrease in the mAFCL in both atria. Subsequent dilatation increased the mAFCL. The amount of CB decreased with dedilatation and increased with dilatation afterward in both atria. Copyright © 2013 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Controlled dilatation of the uterine cervix--an experimental visceral pain model.

PubMed

Bajaj, Priti; Drewes, Asbjørn M; Gregersen, Hans; Petersen, Poul; Madsen, Hans; Arendt-Nielsen, Lars

2002-10-01

Pain originating from the female reproductive organs is a substantial clinical problem to treat. Experimental models may be a tool for the study of visceral pain mechanisms and hence provide information to aid in formulating new treatment strategies. The aim was to develop and evaluate the performance and safety of a model for nociceptive stimulation of the uterine cervix by balloon dilatation using impedance planimetry. Three consecutive (repeated) dilatations at 1 ml/min, an isovolumetric and a fast dilatation at 2 ml/min were performed. Pilot studies were conducted in vitro on hysterectomy specimens, followed by application of the model in 14 healthy females. Subjects indicated the quality of perception and pain during dilatations by verbal reports and the McGill Pain Questionnaire (MPQ), and the intensity by a continuous electronic visual analog scale. The pain location was marked on an anatomical map. The balloon cross-sectional area (CSA) was measured simultaneously. The experimental procedure was atraumatic. Pain was evoked in all subjects, with referral to the hypogastric and low back regions. The word descriptors on the MPQ and the areas of referred sensations were similar to that seen clinically in abortion, labor and menstrual pain. The pain intensity correlated with balloon CSA (r=0.9, P<0.001). No significant differences were found for the balloon volumes (4.2, 3.8 and 3.9 ml) or CSA (163, 122 and 123 mm(2)) to pain threshold (PT) for repeated dilatations, suggesting the reliability of the model. There was significant correlation between the balloon volume and CSA to reach the PT for single and repeated cervical dilatations. During isovolumetric distension, greater overall pain intensity was demonstrated for the prolonged as compared to the shorter duration cervical stimulation. In conclusion, this is the first human experimental pain model for dilatation of the uterine cervix, providing a safe, controlled, quantifiable stimulus that evoked reliable pain scores. The model thus provides a new possibility to study gynecological pain and may lead to better characterization and treatment of female visceral pain syndromes.

In a Concurrent Memory and Auditory Perception Task, the Pupil Dilation Response Is More Sensitive to Memory Load Than to Auditory Stimulus Characteristics.

PubMed

Zekveld, Adriana A; Kramer, Sophia E; Rönnberg, Jerker; Rudner, Mary

2018-06-19

Speech understanding may be cognitively demanding, but it can be enhanced when semantically related text cues precede auditory sentences. The present study aimed to determine whether (a) providing text cues reduces pupil dilation, a measure of cognitive load, during listening to sentences, (b) repeating the sentences aloud affects recall accuracy and pupil dilation during recall of cue words, and (c) semantic relatedness between cues and sentences affects recall accuracy and pupil dilation during recall of cue words. Sentence repetition following text cues and recall of the text cues were tested. Twenty-six participants (mean age, 22 years) with normal hearing listened to masked sentences. On each trial, a set of four-word cues was presented visually as text preceding the auditory presentation of a sentence whose meaning was either related or unrelated to the cues. On each trial, participants first read the cue words, then listened to a sentence. Following this they spoke aloud either the cue words or the sentence, according to instruction, and finally on all trials orally recalled the cues. Peak pupil dilation was measured throughout listening and recall on each trial. Additionally, participants completed a test measuring the ability to perceive degraded verbal text information and three working memory tests (a reading span test, a size-comparison span test, and a test of memory updating). Cue words that were semantically related to the sentence facilitated sentence repetition but did not reduce pupil dilation. Recall was poorer and there were more intrusion errors when the cue words were related to the sentences. Recall was also poorer when sentences were repeated aloud. Both behavioral effects were associated with greater pupil dilation. Larger reading span capacity and smaller size-comparison span were associated with larger peak pupil dilation during listening. Furthermore, larger reading span and greater memory updating ability were both associated with better cue recall overall. Although sentence-related word cues facilitate sentence repetition, our results indicate that they do not reduce cognitive load during listening in noise with a concurrent memory load. As expected, higher working memory capacity was associated with better recall of the cues. Unexpectedly, however, semantic relatedness with the sentence reduced word cue recall accuracy and increased intrusion errors, suggesting an effect of semantic confusion. Further, speaking the sentence aloud also reduced word cue recall accuracy, probably due to articulatory suppression. Importantly, imposing a memory load during listening to sentences resulted in the absence of formerly established strong effects of speech intelligibility on the pupil dilation response. This nullified intelligibility effect demonstrates that the pupil dilation response to a cognitive (memory) task can completely overshadow the effect of perceptual factors on the pupil dilation response. This highlights the importance of taking cognitive task load into account during auditory testing.This is an open access article distributed under the Creative Commons Attribution License 4.0 (CCBY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

21 CFR 876.5365 - Esophageal dilator.

Code of Federal Regulations, 2010 CFR

2010-04-01

... and weighted with mercury or a metal olive-shaped weight that slides on a guide, such as a string or... esophageal or gastrointestinal bougies and the esophageal dilator (metal olive). (b) Classification. Class II...

Pore dilation reconsidered

PubMed Central

Bean, Bruce P

2015-01-01

Previous experiments have suggested that many P2X family channels undergo a time-dependent process of pore dilation when activated by ATP. Li et al. now propose a different interpretation of the key experiments. PMID:26505561

SGS Modeling of the Internal Energy Equation in LES of Supersonic Channel Flow

NASA Astrophysics Data System (ADS)

Raghunath, Sriram; Brereton, Giles

2011-11-01

DNS of fully-developed turbulent supersonic channel flows (Reτ = 190) at up to Mach 3 indicate that the turbulent heat fluxes depend only weakly on Mach number, while the viscous dissipation and pressure dilatation do so strongly. Moreover, pressure dilatation makes a significant contribution to the internal energy budget at Mach 3 and higher. The balance between these terms is critical to determining the temperature (and so molecular viscosity) from the internal energy equation and so, in LES of these flows, it is essential to use accurate SGS models for the viscous dissipation and the pressure dilatation. In this talk, we present LES results for supersonic channel flow, using SGS models for these terms that are based on the resolved-scale dilatation, an inverse timescale, and SGS momentum fluxes, which intrinsically represent this Mach number effect.

Use of a very flexible guide wire to permit dilation of complex malignant strictures of the esophagus.

PubMed

Vargas-Tank, L; Ovalle, L; Fernández, C; Mella, B; Estay, R; del Solar, M P; Soto, J R

1995-01-01

Risk of perforation is a major impediment to the use of polyvinyl bougies in palliative dilation of cancerous strictures of the esophagus. We encountered 23 patients with complex malignant strictures in whom initial dilation with Savary-Gilliard bougies was thwarted because attempts to pass a conventional Eder-Puestow guide wire were unsuccessful. As a recourse, we probed these strictures with a very flexible guide wire of the type used to implant prostheses in the biliary tract. The purpose was to establish a passage through which a standard guide wire could then be inserted. The procedure was successful in all but 4 of the 23 patients. We conclude that in such cases the preliminary use of the very flexible guide, even though time-consuming, improves the chance of effective dilation with minimal added risk.

Wavelets on the Group SO(3) and the Sphere S3

NASA Astrophysics Data System (ADS)

Bernstein, Swanhild

2007-09-01

The construction of wavelets relies on translations and dilations which are perfectly given in R. On the sphere translations can be considered as rotations but it difficult to say what are dilations. For the 2-dimensional sphere there exist two different approaches to obtain wavelets which are worth to be considered. The first concept goes back to Freeden and collaborators [2] which defines wavelets by means of kernels of spherical singular integrals. The other concept developed by Antoine and Vandergheynst and coworkers [3] is a purely group theoretical approach and defines dilations as dilations in the tangent plane. Surprisingly both concepts coincides for zonal functions. We will define wavelets on the 3-dimensional sphere by means of kernels of singular integrals and demonstrate that wavelets constructed by Antoine and Vandergheynst for zonal functions meet our definition.

Balloon dilation of sinus ostia in the Department of Defense: Diagnoses, actual indications, and outcomes.

PubMed

Laury, Adrienne M; Bowe, Sarah N; Stramiello, Joshua; McMains, Kevin C

2017-03-01

To determine the primary diagnoses for which balloon catheter dilation (BCD) of sinus ostia is being employed in a profit-blind health care system, the Department of Defense. Retrospective chart review. From January 1, 2011 to December 31, 2013, 319 consecutive patient charts were reviewed for International Classification of Diseases, Ninth Edition (ICD-9) diagnoses, presence of chronic rhinosinusitis (CRS) defined by the European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS), preoperative Lund-Mackay scores, nasal endoscopy findings, sinuses dilated, postoperative outcomes, and complications. Of the 319 patients identified, 217 had sufficient documentation to be included. A CRS ICD-9 code was applied in 182 of 217 (83.9%) and recurrent acute rhinosinusitis in 12 of 217 (5.6%). Only 50.5% of CRS patient charts met criteria using EPOS guidelines. In contrast, 39.6% met the ICD-9 criteria for atypical facial pain. Patients with Lund-Mackay scores ≤ 4 were reviewed for number of sinuses dilated. Eighty-eight of 123 patients (71.5%) had sinuses dilated that were free from opacification/mucosal edema on preoperative imaging. Balloon dilation of sinus ostia has an expanding role in treating sinus disease. In the studied population, BCD is often utilized for alternate indications for which there is currently no evidence of efficacy. Future studies are needed to evaluate the efficacy of this technology in treating these alternate indications. 4. Laryngoscope, 127:544-549, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Adherence to Vaginal Dilation Following High Dose Rate Brachytherapy for Endometrial Cancer

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

Friedman, Lois C., E-mail: Lois.Friedman@UHhospitals.org; Abdallah, Rita; Schluchter, Mark

Purpose: We report demographic, clinical, and psychosocial factors associated with adherence to vaginal dilation and describe the sexual and marital or nonmarital dyadic functioning of women following high dose rate (HDR) brachytherapy for endometrial cancer. Methods and Materials: We retrospectively evaluated women aged 18 years or older in whom early-stage endometrial (IAgr3-IIB) cancers were treated by HDR intravaginal brachytherapy within the past 3.5 years. Women with or without a sexual partner were eligible. Patients completed questionnaires by mail or by telephone assessing demographic and clinical variables, adherence to vaginal dilation, dyadic satisfaction, sexual functioning, and health beliefs. Results: Seventy-eight ofmore » 89 (88%) eligible women with early-stage endometrial cancer treated with HDR brachytherapy completed questionnaires. Only 33% of patients were adherers, based on reporting having used a dilator more than two times per week in the first month following radiation. Nonadherers who reported a perceived change in vaginal dimension following radiation reported that their vaginas were subjectively smaller after brachytherapy (p = 0.013). Adherers reported more worry about their sex lives or lack thereof than nonadherers (p = 0.047). Patients reported considerable sexual dysfunction following completion of HDR brachytherapy. Conclusions: Adherence to recommendations for vaginal dilator use following HDR brachytherapy for endometrial cancer is poor. Interventions designed to educate women about dilator use benefit may increase adherence. Although sexual functioning was compromised, it is likely that this existed before having cancer for many women in our study.« less

Stress and Dilatancy Relation of Methane Hydrate Bearing Sand with Various Fines Content

NASA Astrophysics Data System (ADS)

Hyodo, M.

2016-12-01

This study presents an experimental and numerical study on the shear behaviour of methane hydrate bearing sand with variable confining pressures and methane hydrate saturations. A representative grading curve of Nankai Trough is selected as the grain size distribution of host sand to artificially produce the methane hydrate bearing sand. A shear strength estimation equation for methane hydrate bearing sand from test results is established. A simple constitutive model has been proposed to predict the stress-strain response of methane hydrate bearing sand based on a few well-known relationships. Experimental results indicate that the inclination of stress-dilatancy curve becomes steeper with a rise in methane hydrate saturation. A revised stress-dilatancy equation has been integrated with this simple model to consider the variance in the inclination of stress-dilatancy curve. The mean stress Pcr at critical state when the peak stress ratio reduces to the residual stress ratio increases with the level of methane hydrate saturation. The dilatancy parameter a tends to increase with the methane hydrate saturation. The shear deformability parameter A exhibits a decreasing tendency with the rise in methane hydrate saturation at each confining pressure. This model is capable of reasonably predicting the strength and stiffness enhancement and the dilation behaviour as methane hydrate saturation increases. The volumetric variation from contraction to expansion of MH bearing sand at a lower confining pressure and only pure volumetric contraction a higher confining pressure can be represented by this simple model.

Management Options for Twisted Gastric Tube after Laparoscopic Sleeve Gastrectomy.

PubMed

Abd Ellatif, Mohamed E; Abbas, Ashraf; El Nakeeb, Ayman; Magdy, Alaa; Salama, Asaad F; Bashah, Moataz M; Dawoud, Ibrahim; Gamal, Maged Ali; Sargsyan, Davit

2017-09-01

This study aims to determine the incidence, etiology, and management options for symptomatic gastric obstruction caused by axially twisted sleeve gastrectomy. In this retrospective study, we reviewed medical charts of all morbidly obese patients who underwent laparoscopic sleeve gastrectomy. Patients who developed gastric obstruction symptoms and were diagnosed with twisted sleeve gastrectomy were identified and included in this study. From October 2005 to December 2015, there are 3634 morbidly obese patients who underwent laparoscopic sleeve gastrectomy (LSG). Eighty-six (2.3%) patients developed symptoms of gastric obstruction. Forty-five (1.23%) patients were included in this study. The mean time of presentation was 59.8 days after surgery. Upper GI contrast study was done routinely, and it was positive for axial twist in 37 (82%) patients. Abdominal CT with oral and IV contrast was done in eight (18%) when swallow study was equivocal. Endoscopic treatment was successful in 43 patients (95.5%). Sixteen patients were successfully managed by endoscopic stenting, and 29 patients had balloon dilation. The average numbers of dilation sessions were 1.7. Out of these 29 patients, 18 responded well to a single session of dilatation and did not require any further dilatation sessions. Two patients who failed to respond to three subsequent sessions of balloon dilation underwent laparoscopic adhesiolysis and gastropexy. Endoscopic stenting is an effective tool in management of axial rotation of sleeved stomach. Balloon dilation can also be effective in selected cases. Few cases might require laparoscopic adhesiolysis and gastropexy.

Biomechanical analysis of wrapping of the moderately dilated ascending aorta.

PubMed

Plonek, Tomasz; Rylski, Bartosz; Dumanski, Andrzej; Siedlaczek, Przemyslaw; Kustrzycki, Wojciech

2015-08-01

External wrapping is a surgical method performed to prevent the dilatation of the aorta and to decrease the risk of its dissection and rupture. However, it is also believed to cause degeneration of the aortic wall. A biomechanical analysis was thus performed to assess the stress of the aortic wall subjected to external wrapping. A stress analysis using the finite elements method was carried out on three models: a non-dilated aorta, a moderately dilated aorta and a wrapped aorta. The models were subjected to a pulsatile flow (120/80 mmHg) and a systolic aortic annulus motion of 11 mm. The finite elements analysis showed that the stress exerted on the outer surface of the ascending aorta in the wrapping model (0.05-0.8 MPa) was similar to that observed in the normal aorta (0.03-0.7 MPa) and was lower than in the model of a moderately dilated aorta (0.06-1.4 MPa). The stress on the inner surface of the ascending aorta ranged from 0.2 MPa to 0.4 MPa in the model of the normal aorta, from 0.3 to 1.3 MPa in the model of the dilated aorta and from 0.05 MPa to 0.4 MPa in the wrapping model. The results of this study suggest that the aortic wall is subjected to similar stress following a wrapping procedure to the one present in the normal aorta.

Endoluminal dilatation for embedded hemodialysis catheters: A case-control study of factors associated with embedding and clinical outcomes

PubMed Central

Talreja, Hari; Ryan, Stephen Edward; Graham, Janet; Sood, Manish M.; Hadziomerovic, Adnan; Clark, Edward

2017-01-01

Background With the increasing frequency of tunneled hemodialysis catheter use there is a parallel increase in the need for removal and/or exchange. A small but significant minority of catheters become embedded or ‘stuck’ and cannot be removed by traditional means. Management of embedded catheters involves cutting the catheter, burying the retained fragment with a subsequent increased risk of infections and thrombosis. Endoluminal dilatation may provide a potential safe and effective technique for removing embedded catheters, however, to date, there is a paucity of data. Objectives 1) To determine factors associated with catheters becoming embedded and 2) to determine outcomes associated with endoluminal dilatation Methods All patients with endoluminal dilatation for embedded catheters at our institution since Jan. 2010 were included. Patients who had an embedded catheter were matched 1:3 with patients with uncomplicated catheter removal. Baseline patient and catheter characteristics were compared. Outcomes included procedural success and procedure-related infection. Logistic regression models were used to determine factors associated with embedded catheters. Results We matched 15 cases of embedded tunneled catheters with 45 controls. Among patients with embedded catheters, there were no complications with endoluminal dilatation. Factors independently associated with embedded catheters included catheter dwell time (> 2 years) and history of central venous stenosis. Conclusion Embedded catheters can be successfully managed by endoluminal dilatation with minimal complications and factors associated with embedding include dwell times > 2 years and/or with a history of central venous stenosis. PMID:28346468

Pupil-mimicry conditions trust in partners: moderation by oxytocin and group membership

PubMed Central

De Dreu, Carsten K. W.

2017-01-01

Across species, oxytocin, an evolutionarily ancient neuropeptide, facilitates social communication by attuning individuals to conspecifics' social signals, fostering trust and bonding. The eyes have an important signalling function; and humans use their salient and communicative eyes to intentionally and unintentionally send social signals to others, by contracting the muscles around their eyes and pupils. In our earlier research, we observed that interaction partners with dilating pupils are trusted more than partners with constricting pupils. But over and beyond this effect, we found that the pupil sizes of partners synchronize and that when pupils synchronously dilate, trust is further boosted. Critically, this linkage between mimicry and trust was bound to interactions between ingroup members. The current study investigates whether these findings are modulated by oxytocin and sex of participant and partner. Using incentivized trust games with partners from ingroup and outgroup whose pupils dilated, remained static or constricted, this study replicates our earlier findings. It further reveals that (i) male participants withhold trust from partners with constricting pupils and extend trust to partners with dilating pupils, especially when given oxytocin rather than placebo; (ii) female participants trust partners with dilating pupils most, but this effect is blunted under oxytocin; (iii) under oxytocin rather than placebo, pupil dilation mimicry is weaker and pupil constriction mimicry stronger; and (iv) the link between pupil constriction mimicry and distrust observed under placebo disappears under oxytocin. We suggest that pupil-contingent trust is parochial and evolved in social species in and because of group life. PMID:28250181

Suppression of slip and rupture velocity increased by thermal pressurization: Effect of dilatancy

NASA Astrophysics Data System (ADS)

Urata, Yumi; Kuge, Keiko; Kase, Yuko

2013-11-01

investigated the effect of dilatancy on dynamic rupture propagation on a fault where thermal pressurization (TP) is in effect, taking into account permeability varying with porosity; the study is based on three-dimensional (3-D) numerical simulations of spontaneous ruptures obeying a slip-weakening friction law and Coulomb failure criterion. The effects of dilatancy on dynamic ruptures interacting with TP have been often investigated in one- or two-dimensional numerical simulations. The sole 3-D numerical simulation gave attention only to the behavior at a single point on a fault. Moreover, with the sole exception based on a single-degree-freedom spring-slider model, the previous simulations including dilatancy and TP have not considered changes in hydraulic diffusivity. However, the hydraulic diffusivity, which strongly affects TP, can vary as a power of porosity. In this study, we apply a power law relationship between permeability and porosity. We consider both reversible and irreversible changes in porosity, assuming that the irreversible change is proportional to the slip rate and dilatancy coefficient ɛ. Our numerical simulations suggest that the effects of dilatancy can suppress slip and rupture velocity increased by TP. The results reveal that the amount of slip on the fault decreases with increasing ɛ or exponent of the power law, and the rupture velocity is predominantly suppressed by ɛ. This was observed regardless of whether the applied stresses were high or low. The deficit of the final slip in relation to ɛ can be smaller as the fault size is larger.

A pseudo-sound constitutive relationship for the dilatational covariances in compressible turbulence: An analytical theory

NASA Technical Reports Server (NTRS)

Ristorcelli, J. R.

1995-01-01

The mathematical consequences of a few simple scaling assumptions about the effects of compressibility are explored using a simple singular perturbation idea and the methods of statistical fluid mechanics. Representations for the pressure-dilation and dilatational dissipation covariances appearing in single-point moment closures for compressible turbulence are obtained. While the results are expressed in the context of a second-order statistical closure they provide some interesting and very clear physical metaphors for the effects of compressibility that have not been seen using more traditional linear stability methods. In the limit of homogeneous turbulence with quasi-normal large-scales the expressions derived are - in the low turbulent Mach number limit - asymptotically exact. The expressions obtained are functions of the rate of change of the turbulence energy, its correlation length scale, and the relative time scale of the cascade rate. The expressions for the dilatational covariances contain constants which have a precise and definite physical significance; they are related to various integrals of the longitudinal velocity correlation. The pressure-dilation covariance is found to be a nonequilibrium phenomena related to the time rate of change of the internal energy and the kinetic energy of the turbulence. Also of interest is the fact that the representation for the dilatational dissipation in turbulence, with or without shear, features a dependence on the Reynolds number. This article is a documentation of an analytical investigation of the implications of a pseudo-sound theory for the effects of compressibility.

A splice site mutation in a gene encoding for PDK4, a mitochondrial protein, is associated with the development of dilated cardiomyopathy in the Doberman pinscher.

PubMed

Meurs, Kathryn M; Lahmers, Sunshine; Keene, Bruce W; White, Stephen N; Oyama, Mark A; Mauceli, Evan; Lindblad-Toh, Kerstin

2012-08-01

Familial dilated cardiomyopathy is a primary myocardial disease that can result in the development of congestive heart failure and sudden cardiac death. Spontaneous animal models of familial dilated cardiomyopathy exist and the Doberman pinscher dog is one of the most commonly reported canine breeds. The objective of this study was to evaluate familial dilated cardiomyopathy in the Doberman pinscher dog using a genome-wide association study for a genetic alteration(s) associated with the development of this disease in this canine model. Genome-wide association analysis identified an area of statistical significance on canine chromosome 14 (p(raw) = 9.999e-05 corrected for genome-wide significance), fine-mapping of additional SNPs flanking this region localized a signal to 23,774,190-23,781,919 (p = 0.001) and DNA sequencing identified a 16-base pair deletion in the 5' donor splice site of intron 10 of the pyruvate dehydrogenase kinase 4 gene in affected dogs (p < 0.0001). Electron microscopy of myocardium from affected dogs demonstrated disorganization of the Z line, mild to moderate T tubule and sarcoplasmic reticulum dilation, marked pleomorphic mitochondrial alterations with megamitochondria, scattered mitochondria with whorling and vacuolization and mild aggregates of lipofuscin granules. In conclusion, we report the identification of a splice site deletion in the PDK4 gene that is associated with the development of familial dilated cardiomyopathy in the Doberman pinscher dog.

Effect of cataract surgery and pupil dilation on iris pattern recognition for personal authentication.

PubMed

Dhir, L; Habib, N E; Monro, D M; Rakshit, S

2010-06-01

The purpose of this study was to investigate the effect of cataract surgery and pupil dilation on iris pattern recognition for personal authentication. Prospective non-comparative cohort study. Images of 15 subjects were captured before (enrolment), and 5, 10, and 15 min after instillation of mydriatics before routine cataract surgery. After cataract surgery, images were captured 2 weeks thereafter. Enrolled and test images (after pupillary dilation and after cataract surgery) were segmented to extract the iris. This was then unwrapped onto a rectangular format for normalization and a novel method using the Discrete Cosine Transform was applied to encode the image into binary bits. The numerical difference between two iris codes (Hamming distance, HD) was calculated. The HD between identification and enrolment codes was used as a score and was compared with a confidence threshold for specific equipment, giving a match or non-match result. The Correct Recognition Rate (CRR) and Equal Error Rates (EERs) were calculated to analyse overall system performance. After cataract surgery, perfect identification and verification was achieved, with zero false acceptance rate, zero false rejection rate, and zero EER. After pupillary dilation, non-elastic deformation occurs and a CRR of 86.67% and EER of 9.33% were obtained. Conventional circle-based localization methods are inadequate. Matching reliability decreases considerably with increase in pupillary dilation. Cataract surgery has no effect on iris pattern recognition, whereas pupil dilation may be used to defeat an iris-based authentication system.

Slip and Dilation Tendency Analysis of the San Emidio Geothermal Area

DOE Data Explorer

Faulds, James E.

2013-12-31

Critically stressed fault segments have a relatively high likelihood of acting as fluid flow conduits (Sibson, 1994). As such, the tendency of a fault segment to slip (slip tendency; Ts; Morris et al., 1996) or to dilate (dilation tendency; Td; Ferrill et al., 1999) provides an indication of which faults or fault segments within a geothermal system are critically stressed and therefore likely to transmit geothermal fluids. The slip tendency of a surface is defined by the ratio of shear stress to normal stress on that surface: Ts = τ / σn (Morris et al., 1996). Dilation tendency is defined by the stress acting normal to a given surface: Td = (σ1-σn) / (σ1-σ3) (Ferrill et al., 1999). Slip and dilation were calculated using 3DStress (Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by ambient stress conditions. Values range from a maximum of 1, a fault plane ideally oriented to slip or dilate under ambient stress conditions to zero, a fault plane with no potential to slip or dilate. Slip and dilation tendency values were calculated for each fault in the focus study areas at, McGinness Hills, Neal Hot Springs, Patua, Salt Wells, San Emidio, and Tuscarora on fault traces. As dip is not well constrained or unknown for many faults mapped in within these we made these calculations using the dip for each fault that would yield the maximum slip tendency or dilation tendency. As such, these results should be viewed as maximum tendency of each fault to slip or dilate. The resulting along-fault and fault-to-fault variation in slip or dilation potential is a proxy for along fault and fault-to-fault variation in fluid flow conduit potential. Stress Magnitudes and directions Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes, 2010; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012; Moeck et al., 2010; Moos and Ronne, 2010 and Reinecker et al., 2005) as well as local stress information if applicable. For faults within these focus systems we applied either a normal faulting stress regime where the vertical stress (sv) is larger than the maximum horizontal stress (shmax) which is larger than the minimum horizontal stress (sv>shmax>shmin) or strike-slip faulting stress regime where the maximum horizontal stress (shmax) is larger than the vertical stress (sv) which is larger than the minimum horizontal stress (shmax >sv>shmin) depending on the general tectonic province of the system. Based on visual inspection of the limited stress magnitude data in the Great Basin we used magnitudes such that shmin/shmax = .527 and shmin/sv= .46, which are consistent with complete and partial stress field determinations from Desert Peak, Coso, the Fallon area and Dixie valley (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes, 2011; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012). Slip and dilation tendency for the San Emidio geothermal field was calculated based on the faults mapped Tuscarora area (Rhodes, 2011). The San Emidio area lies in the Basin and Range Province, as such we applied a normal faulting stress regime to the San Emidio area faults, with a minimum horizontal stress direction oriented 115, based on inspection of local and regional stress determinations, as explained above. This is consistent with the shmin determined through inversion of fault data by Rhodes (2011). Under these stress conditions north-northeast striking, steeply dipping fault segments have the highest dilation tendency, while north-northeast striking 60° dipping fault segments have the highest tendency to slip. Interesting, the San Emidio geothermal field lies in an area of primarily north striking faults, which...

Slip and Dilation Tendency Analysis of the Salt Wells Geothermal Area

DOE Data Explorer

Faulds, James E.

2013-12-31

Critically stressed fault segments have a relatively high likelihood of acting as fluid flow conduits (Sibson, 1994). As such, the tendency of a fault segment to slip (slip tendency; Ts; Morris et al., 1996) or to dilate (dilation tendency; Td; Ferrill et al., 1999) provides an indication of which faults or fault segments within a geothermal system are critically stressed and therefore likely to transmit geothermal fluids. The slip tendency of a surface is defined by the ratio of shear stress to normal stress on that surface: Ts = τ / σn (Morris et al., 1996). Dilation tendency is defined by the stress acting normal to a given surface: Td = (σ1-σn) / (σ1-σ3) (Ferrill et al., 1999). Slip and dilation were calculated using 3DStress (Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by ambient stress conditions. Values range from a maximum of 1, a fault plane ideally oriented to slip or dilate under ambient stress conditions to zero, a fault plane with no potential to slip or dilate. Slip and dilation tendency values were calculated for each fault in the focus study areas at, McGinness Hills, Neal Hot Springs, Patua, Salt Wells, San Emidio, and Tuscarora on fault traces. As dip is not well constrained or unknown for many faults mapped in within these we made these calculations using the dip for each fault that would yield the maximum slip tendency or dilation tendency. As such, these results should be viewed as maximum tendency of each fault to slip or dilate. The resulting along-fault and fault-to-fault variation in slip or dilation potential is a proxy for along fault and fault-to-fault variation in fluid flow conduit potential. Stress Magnitudes and directions Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes, 2010; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012; Moeck et al., 2010; Moos and Ronne, 2010 and Reinecker et al., 2005) as well as local stress information if applicable. For faults within these focus systems we applied either a normal faulting stress regime where the vertical stress (sv) is larger than the maximum horizontal stress (shmax) which is larger than the minimum horizontal stress (sv>shmax>shmin) or strike-slip faulting stress regime where the maximum horizontal stress (shmax) is larger than the vertical stress (sv) which is larger than the minimum horizontal stress (shmax >sv>shmin) depending on the general tectonic province of the system. Based on visual inspection of the limited stress magnitude data in the Great Basin we used magnitudes such that shmin/shmax = .527 and shmin/sv= .46, which are consistent with complete and partial stress field determinations from Desert Peak, Coso, the Fallon area and Dixie valley (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes, 2011; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012). Slip and dilation tendency for the Salt Wells geothermal field was calculated based on the faults mapped in the Bunejug Mountains quadrangle (Hinz et al., 2011). The Salt Wells area lies in the Basin and Range Province (N. Hinz personal comm.) As such we applied a normal faulting stress regime to the Salt Wells area faults, with a minimum horizontal stress direction oriented 105, based on inspection of local and regional stress determinations. Under these stress conditions north-northeast striking, steeply dipping fault segments have the highest dilation tendency, while north-northeast striking 60° dipping fault segments have the highest tendency to slip. Several such faults intersect in high density in the core of the accommodation zone in the Bunejug Mountains and local to the Salt Wells geothermal .

Right ventricular remodeling and dysfunction with subsequent annular dilatation and tethering as a mechanism of isolated tricuspid regurgitation.

PubMed

Seo, Hye-Sun; Ha, Jong-Won; Moon, Jae Youn; Choi, Eui-Young; Rim, Se-Joong; Jang, Yangsoo; Chung, Namsik; Shim, Won-Heum; Cho, Seung-Yun; Kim, Sung Soon

2008-10-01

Secondary tricuspid regurgitation (TR) as a result of pulmonary hypertension and/or left-sided heart disease is caused by tricuspid valve (TV) annular dilatation and tethering of the tricuspid leaflet after right ventricular (RV) dilatation. However, the mechanism of isolated TR without significant pulmonary hypertension remains unknown. The present study investigated the RV function and TV deformations in patients with isolated TR to find out the mechanism and etiology of the disease. Twelve patients with isolated, severe TR were included. RV area, volume, ejection fraction (EF), tenting distance and tenting area were measured. These parameters were compared with 12 age-and gender-matched controls and 12 patients with secondary TR. The cause of isolated TR was incomplete coaptation associated with annular dilatation without other problems. Compared with the controls, RV end-diastolic volumes and annular diameters were significantly larger and RVEF was significantly lower in patients with isolated TR. Tenting area and tenting distance were also significantly higher. However, there were no significant differences in these parameters between patients with isolated and secondary TR. Isolated TR was associated with RV remodeling, systolic dysfunction and resultant annular dilatation and tethering of tricuspid leaflets.

Expandable right ventricular-to-pulmonary artery conduit: an animal study.

PubMed

Boudjemline, Younes; Laborde, François; Pineau, Emmanuelle; Mollet, Alix; Abadir, Sylvia; Borenstein, Nicolas; Behr, Luc; Bonhoeffer, Philipp

2006-06-01

This study was performed to assess a new vascular stent graft as an expandable valved conduit for right ventricular outflow tract (RVOT) reconstruction in sheep. Conduits were constructed by sewing an 18-mm valved conduit inside a stent. Crimped to 16 mm, they were implanted either under or without extracorporeal circulation in seven (group A) and in five (group B) sheep, respectively. Six weeks and 3 mo after their insertion, conduits were dilated intraluminally. A valved stent was implanted percutaneously into conduits before they were killed. Two animals from group A recovered normally, whereas five animals had a complicated postoperative course. In group B, one died acutely due to kinking of the conduit. Balloon dilatations were performed in all surviving animals. First dilatations had a slight impact on valvular function in all animals but one, whereas second dilatations led to significant PR in all. Transcatheter valve implantation was performed successfully. When animals were killed, no bleeding was found around the surgically implanted device. In conclusion, we designed a biologic valved conduit for RVOT reconstruction that can be dilated sequentially to follow animal growth. This new device can have tremendous applications in children with congenital heart diseases involving the RVOT.

The effects of uncinectomy and natural ostial dilatation on maxillary sinus ventilation: a clinical experimental study.

PubMed

Kutluhan, Ahmet; Şalvız, Mehti; Bozdemir, Kazım; Kanbak, Orhan; Ulu, Mustafa; Yalçıner, Gökhan; Bilgen, Akif Sinan

2011-04-01

The purpose of this study was to determine the effect of uncinectomy without sinusotomy and natural ostial dilatation on maxillary sinus ventilation in chronic rhinosinusitis. Twenty patients with chronic rhinosinusitis were included in this study. The patients were randomly divided into two groups. Group 1 consisted of patients with uncinectomy (n = 10), while group 2 was made up of patients treated with natural ostial dilatation (n = 10). The CO(2) tension and pressure levels of the maxillary sinus during inspiration and expiration phases were obtained and compared before and after the procedures within and between the groups. The mean CO(2) tension levels in both groups were significantly decreased after the procedures. The mean maxillary sinus pressure during inspiration was significantly decreased to a negative value after uncinectomy; however, no significant change was observed during expiration. There were no significant changes in maxillary sinus pressures after natural ostial dilatation procedure. Both uncinectomy and natural ostial dilatation seem to be equally effective in decreasing maxillary sinus pCO(2) levels. The effects of decreased maxillary sinus pressure during inspiration after uncinectomy on mucociliary clearance and development mechanisms of chronic rhinosinusitis seem to be worth investigating.

[Preventing complications due to dilatation by intracervical application of a prostaglandin-gel (author's transl)].

PubMed

Kühnie, H; Grande, P; Kuhn, W

1977-08-01

Mechanical injuries by dilatating the cervix uteri for artificial abortion may lead to intra- and postoperative complications; of these cervical insufficiency during subsequent pregnancy is of main importance. In order to prevent this complication 160 patients in the 8th to 18th week of pregnancy, who were going to have a legal abortion, were treated with a gel consisting of 3--5 mg Prostaglandin F2alpha which was applicated in the cervix uteri. In more than 90% of these cases a mechanical dilatation was not necessary afterwards. Generally the cervix uteri was softened and dilatated to Hegar 12. 32% of the patients had a spontaneous abortion. Therefore only a curettage without a dilatation had to be performed. Complications due to the application of the gel did not occur. The combined application of the gel with the extraamnial instillation of Prostaglandin for artificial abortion during the second trimenon reduced by half the period of indwelling of the intrauterine foley-catheter and therewith the risk of infection as well as the period of labour pains. Further possible ways of applicating the Prostaglandin gel in gynecology and obstetrics concern missed abortion, intrauterine death, and cervical dystocia during delivery.

Fibre-endoscopic dilatation of peptic oesophageal strictures.

PubMed

Salo, J A; Ala-Kulju, K; Kalima, T

1987-01-01

51 patients with dysphagia caused by peptic oesophageal stricture due to primary or secondary reflux oesophagitis were treated by fibre-endoscope and Eder-Puestow dilatations under local anaesthesia and sedation, between 1976 and 1984. There was one death (2%) attributable to the procedure (perforation) and complications arose in three (6%) patients (perforation, pneumonia). The dilatation was successful in 96% but two patients (4%) had to be operated on because of undilatable stricture. Follow-up data was available for the other 44 patients for periods of one to eight (mean 2.8) years later. The stricture was cured by dilatation and antireflux treatment (conservative or operative) in all patients and 98% of them were able to eat solid food and improve their nutritional status. During follow-up 22 patients (50%) were asymptomatic and 22 (50%) had dysphagia or/and reflux symptoms. At endoscopy oesophagitis was healed with conservative or operative treatment in 25 patients (57%). It is concluded that fibre-endoscopic dilatation of peptic oesophageal strictures with the Eder-Puestow system combined with conservative or operative antireflux treatment, is a simple and safe procedure and gives good results in almost all patients. Surgical procedures aimed at total correction of the stricture are indicated only rarely in intractable cases.

Cardiovascular Implications of Erectile Dysfunction

MedlinePlus

... the penis are not able to dilate during sexual stimulation because of endothelial dysfunction, the penis cannot fill ... blood to the penis to dilate better during sexual stimulation. The PDE5-Is decrease blood pressure a little ...

Status of therapeutic gene transfer to treat canine dilated cardiomyopathy in dogs.

PubMed

Sleeper, Meg M; Bish, Lawrence T; Sweeney, H Lee

2010-07-01

Therapeutic gene transfer holds promise as a way to treat dilated cardiomyopathy from any underlying cause because the approach attempts to address metabolic disturbances that occur at the molecular level of the failing heart. Calcium-handling abnormalities and increased rates of apoptosis are abnormalities that occur in many types of heart disease, and gene therapies that target these metabolic defects have proven to be beneficial in numerous rodent models of heart disease. The authors are currently evaluating this approach to treat canine idiopathic dilated cardiomyopathy.

Damping of drop oscillations by surfactants and surface viscosity

NASA Technical Reports Server (NTRS)

Rush, Brian M.; Nadim, Ali

1999-01-01

An energy equation is derived for the general case of a viscous drop suspended in a viscous medium with surfactants contaminating the interface. It contains terms that clearly identify dissipation contributions from the viscous effects in the bulk fluids, surface shear and dilatational viscosity effects at the interface, and surfactant transport. An efficient boundary integral method is developed which incorporates the effects of a constant surface dilatational viscosity in simulations of an oscillating two-dimensional inviscid drop. Surface dilatational viscosity is shown to have a significant damping effect on the otherwise undamped inviscid oscillations.

Valve-sparing reimplantation for neoaortic root dilatation and regurgitation with an unbalanced cusp after the arterial switch operation.

PubMed

Yoneyama, Fumiya; Okamura, Toru; Harada, Yorikazu; Okita, Yutaka

2018-02-01

A 13-year-old male presented with neoaortic root dilatation and severe aortic valve regurgitation 13 years following an arterial switch operation. The valve cusps were unbalanced due to an enlarged non-coronary cusp. A valve-sparing reimplantation with a cusp plication was performed which resulted in a competent valve with trivial regurgitation. Thus, even in an unbalanced cusp, valve-sparing reimplantation can be used for neoaortic root dilatation and valve regurgitation after an arterial switch operation. © 2018 Wiley Periodicals, Inc.

Dilated cardiomyopathy and severe heart failure. An update for pediatricians.

PubMed

Caviedes Bottner, Paola; Córdova Fernández, Tamara; Larraín Valenzuela, Marcos; Cruces Romero Presentación de Casos Clínicos, Pablo

2018-06-01

Dilated cardiomyopathy is the main cause of heart failure leading to heart transplant. Its prognosis is variable and depends on the etiology, the patient's age at onset, and the severity. The management of dilated cardiomyopathy is aimed at minimizing symptoms and preventing disease progression; it requires a comprehensive screening for comorbidities and the prevention of complications to improve the overall status of these children and mitigate their prognosis. Here we present a review oriented at the multidisciplinary management that pediatricians should consider when seeing these patients. Sociedad Argentina de Pediatría.

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

PubMed

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

2015-05-01

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

[Right ventricular dilatation in patients with coronary heart disease without myocardial infarction: According to the data of the Coronary Angiography Surgery Registry].

PubMed

Kuznetsov, V A; Yaroslavskaya, E I; Pushkarev, G S; Krinochkin, D V; Bessonov, I S; Gorbatenko, E A

2015-01-01

To identify factors associated with right ventricular (RV) dilatation in patients with coronary heart disease (CHD) without prior myocardial infarction (Ml). Out of 16 839 patents from the Coronary Angiography Surgery Registry, the investigators selected patients with >75% stenosis in at least one coronary artery without acute or prior MI: 75 patients with echocardiographically detected RV dilatation and 1134 without RV dilatation. Among the patients with RV dilatation, there were more men (92% versus 80.2%; p=0.01 2). In this group, the mean body mass index (BMI) was higher (31.7±5.2 kg/m2 versus 30.1±4.7 kg/m2; p=0.01 9); there was more commonly higher NYHA functional class (FC) (III) chronic heart failure (CHF) (22.2% versus 12.5%; p=0.002), clinically relevant mitral regurgitation (29.4% versus 4.0%; all ps<0.001), and cardiac rhythm and conduction disturbances (45.5% versus 17.8%; p<0.001) in rarer severe FC (III-IV) exertional angina (30.3% versus 52.8%; p=0.007). The groups were different as evidenced by coronarography and major blood biochemical indicators. Decreased myocardial contractility (odds ratio (OR), 4.22; p=0.002), male sex (OR, 4.03;p=0.007), cardiac rhythm and conduction disturbances (OR, 2.98; p<0.001), clinically relevant mitral regurgitation (OR, 2.34; p=0.001); higher FC CHF (OR, 1.87; p=0.034), BMI (OR, 1.08; p=0.01 0), and lower FC exertional angina (OR, 0.42; p=0.001) demonstrated an independent relationship to RV dilatation, as evidenced by a multivariateanalysis. In the patients with CHD without MI, RV dilatation is independently related to male sex, left ventricular functional characteristics, and higher BMI.

Elevated pressure causes endothelial dysfunction in mouse carotid arteries by increasing local angiotensin signaling

PubMed Central

Zhao, Yingzi; Flavahan, Sheila; Leung, Susan W.; Xu, Aimin; Vanhoutte, Paul M.

2014-01-01

Experiments were performed to determine whether or not acute exposure to elevated pressure would disrupt endothelium-dependent dilatation by increasing local angiotensin II (ANG II) signaling. Vasomotor responses of mouse-isolated carotid arteries were analyzed in a pressure myograph at a control transmural pressure (PTM) of 80 mmHg. Acetylcholine-induced dilatation was reduced by endothelial denudation or by inhibition of nitric oxide synthase (NG-nitro-l-arginine methyl ester, 100 μM). Transient exposure to elevated PTM (150 mmHg, 180 min) inhibited dilatation to acetylcholine but did not affect responses to the nitric oxide donor diethylamine NONOate. Elevated PTM also increased endothelial reactive oxygen species, and the pressure-induced endothelial dysfunction was prevented by the direct antioxidant and NADPH oxidase inhibitor apocynin (100 μM). The increase in endothelial reactive oxygen species in response to elevated PTM was reduced by the ANG II type 1 receptor (AT1R) antagonists losartan (3 μM) or valsartan (1 μM). Indeed, elevated PTM caused marked expression of angiotensinogen, the precursor of ANG II. Inhibition of ANG II signaling, by blocking angiotensin-converting enzyme (1 μM perindoprilat or 10 μM captopril) or blocking AT1Rs prevented the impaired response to acetylcholine in arteries exposed to 150 mmHg but did not affect dilatation to the muscarinic agonist in arteries maintained at 80 mmHg. After the inhibition of ANG II, elevated pressure no longer impaired endothelial dilatation. In arteries treated with perindoprilat to inhibit endogenous formation of the peptide, exogenous ANG II (0.3 μM, 180 min) inhibited dilatation to acetylcholine. Therefore, elevated pressure rapidly impairs endothelium-dependent dilatation by causing ANG expression and enabling ANG II-dependent activation of AT1Rs. These processes may contribute to the pathogenesis of hypertension-induced vascular dysfunction and organ injury. PMID:25485905

Elevated pressure causes endothelial dysfunction in mouse carotid arteries by increasing local angiotensin signaling.

PubMed

Zhao, Yingzi; Flavahan, Sheila; Leung, Susan W; Xu, Aimin; Vanhoutte, Paul M; Flavahan, Nicholas A

2015-02-15

Experiments were performed to determine whether or not acute exposure to elevated pressure would disrupt endothelium-dependent dilatation by increasing local angiotensin II (ANG II) signaling. Vasomotor responses of mouse-isolated carotid arteries were analyzed in a pressure myograph at a control transmural pressure (PTM) of 80 mmHg. Acetylcholine-induced dilatation was reduced by endothelial denudation or by inhibition of nitric oxide synthase (NG-nitro-L-arginine methyl ester, 100 μM). Transient exposure to elevated PTM (150 mmHg, 180 min) inhibited dilatation to acetylcholine but did not affect responses to the nitric oxide donor diethylamine NONOate. Elevated PTM also increased endothelial reactive oxygen species, and the pressure-induced endothelial dysfunction was prevented by the direct antioxidant and NADPH oxidase inhibitor apocynin (100 μM). The increase in endothelial reactive oxygen species in response to elevated PTM was reduced by the ANG II type 1 receptor (AT1R) antagonists losartan (3 μM) or valsartan (1 μM). Indeed, elevated PTM caused marked expression of angiotensinogen, the precursor of ANG II. Inhibition of ANG II signaling, by blocking angiotensin-converting enzyme (1 μM perindoprilat or 10 μM captopril) or blocking AT1Rs prevented the impaired response to acetylcholine in arteries exposed to 150 mmHg but did not affect dilatation to the muscarinic agonist in arteries maintained at 80 mmHg. After the inhibition of ANG II, elevated pressure no longer impaired endothelial dilatation. In arteries treated with perindoprilat to inhibit endogenous formation of the peptide, exogenous ANG II (0.3 μM, 180 min) inhibited dilatation to acetylcholine. Therefore, elevated pressure rapidly impairs endothelium-dependent dilatation by causing ANG expression and enabling ANG II-dependent activation of AT1Rs. These processes may contribute to the pathogenesis of hypertension-induced vascular dysfunction and organ injury. Copyright © 2015 the American Physiological Society.

Role of Cervical Length Measurement for Preterm Delivery Prediction in Women With Threatened Preterm Labor and Cervical Dilatation.

PubMed

Hiersch, Liran; Melamed, Nir; Aviram, Amir; Bardin, Ron; Yogev, Yariv; Ashwal, Eran

2016-12-01

To compare the accuracy and cutoff points for cervical length for predicting preterm delivery in women with threatened preterm labor between those with a closed cervix and cervical dilatation. We conducted a retrospective cohort study of women with singleton pregnancies with threatened preterm labor before 34 weeks. The accuracy of cervical length for predicting preterm delivery was compared between women with cervical dilatation (0.5-3 cm) and those with a closed cervix. The predictive accuracy of cervical length for spontaneous preterm delivery was analyzed with several outcome-specific thresholds. Overall, 1068 women with threatened preterm labor met the inclusion criteria; of them, 276 (25.8%) had cervical dilatation, and 792 (74.2%) had a closed cervix. The risk of preterm delivery before 37 weeks was significantly higher in the cervical dilatation group than the closed cervix group, as well as a shorter assessment-to-delivery interval of within 14 days (P = .001 and .004, respectively). On a multivariable analysis, cervical length was independently associated with the risk of preterm delivery in both groups. There was no significant difference between women with cervical dilatation and those with a closed cervix regarding the area under the receiver operating characteristic curves of cervical length for prediction of preterm delivery before 37 (0.674 versus 0.618; P = .18) and 34 (0.628 versus 0.640; P = .88) weeks and an assessment-to-delivery interval of 14 days (0.686 versus 0.660; P= .72). The negative predictive value of cervical length ranged from 77.4% to 95.7% depending on the different thresholds used. Cervical length was significantly associated with the risk of preterm delivery in women presenting with threatened preterm labor and cervical dilatation of less than 3 cm. However, the predictive accuracy of cervical length as a single measure was relatively limited. © 2016 by the American Institute of Ultrasound in Medicine.

Experimental Investigation on Dilation Mechanisms of Land-Facies Karamay Oil Sand Reservoirs under Water Injection

NASA Astrophysics Data System (ADS)

Lin, Botao; Jin, Yan; Pang, Huiwen; Cerato, Amy B.

2016-04-01

The success of steam-assisted gravity drainage (SAGD) is strongly dependent on the formation of a homogeneous and highly permeable zone in the land-facies Karamay oil sand reservoirs. To accomplish this, hydraulic fracturing is applied through controlled water injection to a pair of horizontal wells to create a dilation zone between the dual wells. The mechanical response of the reservoirs during this injection process, however, has remained unclear for the land-facies oil sand that has a loosely packed structure. This research conducted triaxial, permeability and scanning electron microscopy (SEM) tests on the field-collected oil sand samples. The tests evaluated the influences of the field temperature, confining stress and injection pressure on the dilation mechanisms as shear dilation and tensile parting during injection. To account for petrophysical heterogeneity, five reservoir rocks including regular oil sand, mud-rich oil sand, bitumen-rich oil sand, mudstone and sandstone were investigated. It was found that the permeability evolution in the oil sand samples subjected to shear dilation closely followed the porosity and microcrack evolutions in the shear bands. In contrast, the mudstone and sandstone samples developed distinct shear planes, which formed preferred permeation paths. Tensile parting expanded the pore space and increased the permeability of all the samples in various degrees. Based on this analysis, it is concluded that the range of injection propagation in the pay zone determines the overall quality of hydraulic fracturing, while the injection pressure must be carefully controlled. A region in a reservoir has little dilation upon injection if it remains unsaturated. Moreover, a cooling of the injected water can strengthen the dilation potential of a reservoir. Finally, it is suggested that the numerical modeling of water injection in the Karamay oil sand reservoirs must take into account the volumetric plastic strain in hydrostatic loading.

Increase in endothelial cell Ca2+ in response to mouse cremaster muscle contraction

PubMed Central

Duza, Tasmia; Sarelius, Ingrid H

2004-01-01

We addressed the role of endothelial cells (ECs) in metabolic dilatation of skeletal muscle arterioles in anaesthetized mice in situ. Electrical field stimulation was used to contract the cremaster muscle for 15 s at 30 Hz. Diameter was observed using bright field microscopy. In controls, muscle contraction produced a 15.7 ± 1.5 μm dilatation from a baseline of 17.4 ± 1.6 μm. Endothelial denudation (−EC) via intraluminal perfusion of air abolished this response (1.6 ± 1.2 μm in −EC, P < 0.05), identifying endothelium as the primary vascular cell type initiating the dilatation. To investigate the role of EC Ca2+ in metabolic dilatation, arteriolar ECs were loaded with Fluo-4 AM or BAPTA AM by intraluminal perfusion, after which blood flow was re-established. Ca2+ activity of individual ECs was monitored as a function of change from baseline fluorescence using confocal microscopy. In ECs, whole cell Ca2+ increased (>10%, P < 0.05) during muscle contraction, and localized Ca2+ transients were increased (>20%, P < 0.05) during the first minute after contraction. Chelation of EC Ca2+ abolished the dilatations in response to muscle contraction (1.1 ± 0.7 μm, P < 0.05). Inhibition of P1 purinergic receptors (with xanthine amine congener) did not alter the rate of onset of the dilatation (P > 0.05) but decreased its magnitude immediately post stimulation (7.1 ± 0.9 μm, P < 0.05) and during recovery. These findings demonstrate obligatory roles for endothelium and EC Ca2+ during metabolic dilatation in intact arterioles. Furthermore, they suggest that at least two separate pathways mediate the local response, one of which involves stimulation of endothelial P1 purinergic receptors via endogenous adenosine produced during muscle activity. PMID:14694141

Correlates of tricuspid regurgitation as determined by 3D echocardiography: pulmonary arterial pressure, ventricle geometry, annular dilatation, and papillary muscle displacement.

PubMed

Spinner, Erin M; Lerakis, Stamatios; Higginson, Jason; Pernetz, Maria; Howell, Sharon; Veledar, Emir; Yoganathan, Ajit P

2012-01-01

While it is understood that annular dilatation contributes to tricuspid regurgitation (TR), other factors are less clear. The geometry of the right ventricle (RV) and left ventricle (LV) may alter tricuspid annulus size and papillary muscle (PM) positions leading to TR. Three-dimensional echocardiographic images were obtained at Emory University Hospital using a GE Vivid 7 ultrasound system. End-diastolic area was used to classify ventricle geometry: control (n=21), isolated RV dilatation (n=17), isolated LV dilatation (n=13), and both RV and LV dilatation (n=13). GE EchoPAC was used to measure annulus area and position of the PM tips. Patients with RV dilatation had significant (P≤ 0.05) displacement of all PMs apically and the septal PM and posterior PM away from the center of the RV toward the LV. Patients with LV dilatation had significant (P≤0.05) apical displacement of the anterior PM. Pulmonary arterial pressure (r=0.66), annulus area (r=0.51), apical displacement of the anterior PM (r=0.26), posterior PM (r=0.49), and septal PM (r=0.40), lateral displacement of the septal PM (r=0.37) and posterior PM (r=0.40), and tenting area and height (r=0.54, 0.49), were significantly (P≤0.05) correlated to the grade of TR. Ventricle classification (r=0.46) and RV end-diastolic area (r=0.48) also were correlated with the grade of TR. A regression analysis found ventricle classification (P=0.001), pulmonary arterial pressure (P≤0.001) annulus area (P=0.027), and apical displacement of the anterior PM (P=0.061) to be associated with the grade of TR. Alterations in ventricular geometry can lead to TR by altering both tricuspid annulus size and PM position. Understanding these geometric interactions with the aim of correcting pathological alterations of the tricuspid valve apparatus may lead to more robust repairs.

Endoscopic Treatment of Biliary Stenosis in Patients with Alveolar Echinococcosis--Report of 7 Consecutive Patients with Serial ERC Approach.

PubMed

Stojkovic, Marija; Junghanss, Thomas; Veeser, Mira; Weber, Tim F; Sauer, Peter

2016-02-01

Biliary vessel pathology due to alveolar echicococcosis (AE) results in variable combinations of stenosis, necrosis and inflammation. Modern management strategies for patients with cholestasis are desperately needed. The aim is proof of principle of serial ERC (endoscopic retrograde cholangiography) balloon dilation for AE biliary pathology. Retrospective case series of seven consecutive patients with AE-associated biliary pathology and ERC treatment in an interdisciplinary endoscopy unit at a University Hospital which hosts a national echinococcosis treatment center. The AE patient cohort consists of 106 patients with AE of the liver of which 13 presented with cholestasis. 6/13 received bilio-digestive anastomosis and 7/13 patients were treated by ERC and are reported here. Biliary stricture balloon dilation was performed with 18-Fr balloons at the initial and with 24-Fr balloons at subsequent interventions. If indicated 10 Fr plastic stents were placed. Six patients were treated by repeated balloon dilation and stenting, one by stenting only. After an acute phase of 6 months with repeated balloon dilation, three patients showed "sustained clinical success" and four patients "assisted therapeutic success," of which one has not yet reached the six month endpoint. In one patient, sustained success could not be achieved despite repeated insertion of plastic stents and balloon dilation, but with temporary insertion of a fully covered self-expanding metal stent (FCSEMS). There was no loss to follow up. No major complications were observed. Serial endoscopic dilation is a standard tool in the treatment of benign biliary strictures. Serial endoscopic intervention with balloon dilation combined with benzimidazole treatment can re-establish and maintain biliary duct patency in AE associated pathology and probably contributes to avoid or postpone bilio-digestive anastomosis. This approach is in accordance with current ERC guidelines and is minimally disruptive for patients.

Endoscopic Treatment of Biliary Stenosis in Patients with Alveolar Echinococcosis – Report of 7 Consecutive Patients with Serial ERC Approach

PubMed Central

Stojkovic, Marija; Junghanss, Thomas; Veeser, Mira; Weber, Tim F.; Sauer, Peter

2016-01-01

Background and Aims Biliary vessel pathology due to alveolar echicococcosis (AE) results in variable combinations of stenosis, necrosis and inflammation. Modern management strategies for patients with cholestasis are desperately needed. The aim is proof of principle of serial ERC (endoscopic retrograde cholangiography) balloon dilation for AE biliary pathology. Methods Retrospective case series of seven consecutive patients with AE-associated biliary pathology and ERC treatment in an interdisciplinary endoscopy unit at a University Hospital which hosts a national echinococcosis treatment center. The AE patient cohort consists of 106 patients with AE of the liver of which 13 presented with cholestasis. 6/13 received bilio-digestive anastomosis and 7/13 patients were treated by ERC and are reported here. Biliary stricture balloon dilation was performed with 18-Fr balloons at the initial and with 24-Fr balloons at subsequent interventions. If indicated 10 Fr plastic stents were placed. Results Six patients were treated by repeated balloon dilation and stenting, one by stenting only. After an acute phase of 6 months with repeated balloon dilation, three patients showed “sustained clinical success” and four patients “assisted therapeutic success,” of which one has not yet reached the six month endpoint. In one patient, sustained success could not be achieved despite repeated insertion of plastic stents and balloon dilation, but with temporary insertion of a fully covered self-expanding metal stent (FCSEMS). There was no loss to follow up. No major complications were observed. Conclusions Serial endoscopic dilation is a standard tool in the treatment of benign biliary strictures. Serial endoscopic intervention with balloon dilation combined with benzimidazole treatment can re-establish and maintain biliary duct patency in AE associated pathology and probably contributes to avoid or postpone bilio-digestive anastomosis. This approach is in accordance with current ERC guidelines and is minimally disruptive for patients. PMID:26910822

Vascular endothelial function and oxidative stress mechanisms in patients with Behçet's syndrome.

PubMed

Chambers, J C; Haskard, D O; Kooner, J S

2001-02-01

We sought to test the hypothesis that vascular endothelial function is impaired in Behçet's syndrome and reflects increased levels of oxidative stress. Behçet's syndrome is a multisystem inflammatory disorder commonly complicated by vascular thrombosis and arterial aneurysm formation. The precise mechanisms underlying vascular disease in Behçet's syndrome are not known. We studied 19 patients with Behçet's syndrome (18 to 50 years old, 9 men) and 21 healthy volunteers (18 to 50 years old, 10 men). Brachial artery flow-mediated dilation (endothelium-dependent), and nitroglycerin (NTG)-induced dilation (endothelium-independent) were measured. To investigate oxidative stress mechanisms, vascular studies were repeated 1 h after administration of vitamin C (1 g, intravenous) in 12 patients and 12 control subjects. Flow-mediated dilation was reduced in patients with Behcet's syndrome as compared with control subjects (0.7 +/- 0.9% vs. 5.7 +/- 0.9%, p = 0.001). In contrast, there were no significant differences in the brachial artery diameter (4.2 +/- 0.2 vs. 4.0 +/- 0.2 mm, p = 0.47) or NTG-induced dilation (19.7 +/- 1.9% vs. 19.7 +/- 1.2%, p = 0.98). In regression analysis, Behçet's syndrome was associated with impaired flow-mediated dilation independent of age, gender, brachial artery diameter, blood pressure, cholesterol and glucose. Vitamin C increased flow-mediated dilation in Behçet's syndrome (0.2 +/- 0.7% to 3.5 +/- 1.0%, p = 0.002), but not in control subjects (4.3 +/- 0.6% to 4.7 +/- 0.4%, p = 0.51). In both groups, NTG-induced dilation and brachial artery diameter were unchanged after vitamin C treatment. Vascular endothelial function is impaired in Behcet's syndrome and can be rapidly improved by vitamin C treatment. Our results support a role for oxidative stress in the pathophysiology of Behçet's syndrome and provide a rationale for therapeutic studies aimed at reducing vascular complications in this disorder.

Idiopathic dilated cardiomyopathy: computerized anatomic study of relashionship between septal and free left ventricle wall

PubMed Central

Juliani, Paulo Sérgio; da Costa, Éder França; Correia, Aristides Tadeu; Monteiro, Rosangela; Jatene, Fabio Biscegli

2014-01-01

Introduction A feature of dilated cardiomyopathy is the deformation of ventricular cavity, which contributes to systolic dysfunction. Few studies have evaluated this deformation bearing in mind ventricular regions and segments of the ventricle, which could reveal important details of the remodeling process, supporting a better understanding of its role in functional impairment and the development of new therapeutic strategies. Objective To evaluate if, in basal, equatorial and apical regions, increased internal transverse perimeter of left ventricle in idiopathic dilated cardiomyopathy occurs proportionally between the septal and non-septal segment. Methods We performed an anatomical study with 28 adult hearts from human cadavers. One group consisted of 18 hearts with idiopathic dilated cardiomyopathy and another group with 10 normal hearts. After lamination and left ventricle digital image capture, in three different regions (base, equator and apex), the transversal internal perimeter of left ventricle was divided into two segments: septal and not septal. These segments were measured by proper software. It was established an index of proportionality between these segments, called septal and non-septal segment index. Then we determined whether this index was the same in both groups. Results Among patients with normal hearts and idiopathic dilated cardiomyopathy, the index of proportionality between the two segments (septal and non-septal) showed no significant difference in the three regions analyzed. The comparison results of the indices NSS/SS among normal and enlarged hearts were respectively: in base 1.99 versus 1.86 (P=0.46), in equator 2.22 versus 2.18 (P=0.79) and in apex 2.96 versus 3.56 (P=0.11). Conclusion In the idiopathic dilated cardiomyopathy, the transversal dilatation of left ventricular internal perimeter occurs proportionally between the segments corresponding to the septum and free wall at the basal, equatorial and apical regions of this chamber. PMID:25372906

[Application of a tape-like bandage for the ascending aorta in its poststenotic dilation and correction of the aortal valve stenosis].

PubMed

Popov, V V; Bol'shak, A A

2014-06-01

The aortal valve prosthesis in combination with a tape-like bandage of ascending aorta application was performed in 106 patients, suffering a failure with predominance of the aortal valve stenosis in conjunction with the ascending aorta poststenotic dilation, in a 2005 - 2014 yrs period in the clinic. The hospital lethality have constituted 0.9%. In accordance to echocardiography, the ascending aorta diameter preoperatively have constituted (48.7 +/- 1.4) mm at average, before discharge from the hospital--(40.1 +/- 1.2) mm, in late follow-up period--(41.3 +/- 1.2) mm. It is expedient to recommend the original method of a tape-like bandage of ascending aorta from the base of noncoronary sinus in the aortal sinuses dilation (45 mm and more) in combination with the aortal valve prosthesis in poststenotic dilation of ascending aorta.

Discussion of “The relation between dilatancy, effective stress and dispersive pressure in granular avalanches” by P. Bartelt and O. Buser (DOI: 10.1007/s11440-016-0463-7)

USGS Publications Warehouse

Iverson, Richard M.; George, David L.

2016-01-01

A paper recently published by Bartelt and Buser (hereafter identified as “the authors”) aims to clarify relationships between granular dilatancy and dispersive pressure and to question the effective stress principle and its application to shallow granular avalanches (Bartelt and Buser in Act Geotech 11:549–557, 2). The paper also criticizes our own recent work, which utilizes the concepts of evolving dilatancy and effective stress to model the initiation and dynamics of water-saturated landslides and debris flows. Here we first explain why we largely agree with the authors’ views of dilatancy and dispersive pressure as they apply to depth-integrated granular avalanche models, and why we disagree with their views of effective stress and pore-fluid pressure. We conclude by explaining why the authors’ characterization of our recently developed D-Claw model is inaccurate.

Dilatancy and compaction effects on the submerged granular column collapse

NASA Astrophysics Data System (ADS)

Wang, Chun; Wang, Yongqi; Peng, Chong; Meng, Xiannan

2017-10-01

The effects of dilatancy on the collapse dynamics of granular materials in air or in a liquid are studied experimentally and numerically. Experiments show that dilatancy has a critical effect on the collapse of granular columns in the presence of an ambient fluid. Two regimes of the collapse, one being quick and the other being slow, are observed from the experiments and the underlying reasons are analyzed. A two-fluid smoothed particle hydrodynamics model, based on the granular-fluid mixture theory and the critical state theory, is employed to investigate the complex interactions between the solid particles and the ambient water. It is found that dilatancy, resulting in large effective stress and large frictional coefficient between solid particles, helps form the slow regime. Small permeability, representing large inter-phase drag force, also retards the collapse significantly. The proposed numerical model is capable of reproducing these effects qualitatively.

Modified tube gastropexy using a mushroom-tipped silicone catheter for management of gastric dilatation-volvulus in dogs.

PubMed

Belch, A; Rubinos, C; Barnes, D C; Nelissen, P

2017-02-01

To report the short- and long-term complications and clinical outcomes of a cohort of dogs managed for gastric dilatation-volvulus using a modified right-sided tube gastropexy technique. Retrospective case series. Of 31 dogs treated, 29 (93·5%) had an excellent short-term outcome, and gastric dilatation-volvulus did not recur in any dog. Twenty-six dogs (84%) were initially fed via the gastrostomy tube postoperatively; three (9·7%) suffered a major complication including septic peritonitis (n=1), and premature tube removal (n=2). Fourteen dogs (45·1%) had minor complications including mild, self-limiting discharge from the stoma site in 13. Modified tube gastropexy using a mushroom-tipped silicone catheter is an effective and safe surgical method for the management of gastric dilatation-volvulus. The gastrostomy tube allowed early enteral feeding and easy administration of medications, including gastroprotectants. © 2017 British Small Animal Veterinary Association.

Gastroschisis: antenatal sonographic predictors of adverse neonatal outcome.

PubMed

Page, Rachael; Ferraro, Zachary Michael; Moretti, Felipe; Fung, Karen Fung Kee

2014-01-01

The aim of this review was to identify clinically significant ultrasound predictors of adverse neonatal outcome in fetal gastroschisis. A quasi-systematic review was conducted in PubMed and Ovid using the key terms "gastroschisis," "predictors," "outcome," and "ultrasound." A total of 18 papers were included. The most common sonographic predictors were intra-abdominal bowel dilatation (IABD), intrauterine growth restriction (IUGR), and bowel dilatation not otherwise specified (NOS). Three ultrasound markers were consistently found to be statistically insignificant with respect to predicting adverse outcome including abdominal circumference, stomach herniation and dilatation, and extra-abdominal bowel dilatation (EABD). Gastroschisis is associated with several comorbidities, yet there is much discrepancy in the literature regarding which specific ultrasound markers best predict adverse neonatal outcomes. Future research should include prospective trials with larger sample sizes and use well-defined and consistent definitions of the adverse outcomes investigated with consideration given to IABD.

Measurement-induced-nonlocality for Dirac particles in Garfinkle-Horowitz-Strominger dilation space-time

NASA Astrophysics Data System (ADS)

He, Juan; Xu, Shuai; Ye, Liu

2016-05-01

We investigate the quantum correlation via measurement-induced-nonlocality (MIN) for Dirac particles in Garfinkle-Horowitz-Strominger (GHS) dilation space-time. It is shown that the physical accessible quantum correlation decreases as the dilation parameter increases monotonically. Unlike the case of scalar fields, the physical accessible correlation is not zero when the Hawking temperature is infinite owing to the Pauli exclusion principle and the differences between Fermi-Dirac and Bose-Einstein statistics. Meanwhile, the boundary of MIN related to Bell-violation is derived, which indicates that MIN is more general than quantum nonlocality captured by the violation of Bell-inequality. As a by-product, a tenable quantitative relation about MIN redistribution is obtained whatever the dilation parameter is. In addition, it is worth emphasizing that the underlying reason why the physical accessible correlation and mutual information decrease is that they are redistributed to the physical inaccessible regions.

Multi-Detector Row Computed Tomography Findings of Pelvic Congestion Syndrome Caused by Dilated Ovarian Veins

PubMed Central

Eren, Suat

2010-01-01

Objective: To evaluate the efficacy of multi-detector row CT (MDCT) on pelvic congestion syndrome (PCS), which is often overlooked or poorly visualized with routine imaging examination. Materials and Methods: We evaluated the MDCT features of 40 patients with PCS (mean age, 45 years; range, 29–60 years) using axial, coronal, sagittal, 3D volume-rendered, and Maximum Intensity Projection MIP images. Results: MDCT revealed pelvic varices and ovarian vein dilatations in all patients. Bilateral ovarian vein dilatation was present in 25 patients, and 15 patients had unilateral dilatation. While 12 cases of secondary pelvic varices occurred simultaneously with a retroaortic left renal vein, 10 cases were due solely to a mass obstruction or stenosis of venous structures. Conclusion: MDCT is an effective tool in the evaluation of PCS, and it has more advantages than other imaging modalities. PMID:25610142

Percutaneous dilatational tracheostomy following total artificial heart implantation.

PubMed

Spiliopoulos, Sotirios; Dimitriou, Alexandros Merkourios; Serrano, Maria Rosario; Guersoy, Dilek; Autschbach, Ruediger; Goetzenich, Andreas; Koerfer, Reiner; Tenderich, Gero

2015-07-01

Coagulation disorders and an immune-altered state are common among total artificial heart patients. In this context, we sought to evaluate the safety of percutaneous dilatational tracheostomy in cases of prolonged need for mechanical ventilatory support. We retrospectively analysed the charts of 11 total artificial heart patients who received percutaneous dilatational tracheostomy. We focused on early and late complications. We observed no major complications and no procedure-related deaths. Early minor complications included venous oozing (45.4%) and one case of local infection. Late complications, including subglottic stenosis, stomal infection or infections of the lower respiratory tract, were not observed. In conclusion, percutaneous dilatational tracheostomy in total artificial heart patients is safe. Considering the well-known benefits of early tracheotomy over prolonged translaryngeal intubation, we advocate early timing of therapy in cases of prolonged mechanical ventilation. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Endoscopic Management of Benign Esophageal Strictures.

PubMed

Ravich, William J

2017-08-24

This paper presents the author's approach to esophageal dilation. It offers a tailored approach to the application of dilation to specific types of esophageal stenotic lesions. In patients with inflammatory stricture, recent studies confirm the importance of treating the underlying inflammatory condition in order to decrease the rate of recurrence. The paper reviews some of the novel techniques that have been suggested for the treatment of refractory benign esophageal strictures, including incisional therapy, stenting, or the injection steroids or antifibrotic agents. The endoscopist who treats esophageal strictures must be familiar with the tools of the dilation and how they are best applied to specific types of stenotic lesions. If inflammation is present, effective management requires treatment of the inflammatory process in addition to mechanical dilation of the stenotic lesion. Controlled trials of novel approaches to treatment of refractory benign esophageal strictures are limited and will be necessary to determine efficacy.

Pressure-strain energy redistribution in compressible turbulence: return-to-isotropy versus kinetic-potential energy equipartition

NASA Astrophysics Data System (ADS)

Lee, Kurnchul; Venugopal, Vishnu; Girimaji, Sharath S.

2016-08-01

Return-to-isotropy and kinetic-potential energy equipartition are two fundamental pressure-moderated energy redistributive processes in anisotropic compressible turbulence. Pressure-strain correlation tensor redistributes energy among various Reynolds stress components and pressure-dilatation is responsible for energy reallocation between dilatational kinetic and potential energies. The competition and interplay between these pressure-based processes are investigated in this study. Direct numerical simulations (DNS) of low turbulent Mach number dilatational turbulence are performed employing the hybrid thermal Lattice Boltzman method (HTLBM). It is found that a tendency towards equipartition precedes proclivity for isotropization. An evolution towards equipartition has a collateral but critical effect on return-to-isotropy. The preferential transfer of energy from strong (rather than weak) Reynolds stress components to potential energy accelerates the isotropization of dilatational fluctuations. Understanding of these pressure-based redistributive processes is critical for developing insight into the character of compressible turbulence.

Benefits of Balloon-Dilatable Bilateral Pulmonary Artery Banding in Patients With Hypoplastic Left Heart Syndrome and Other Complex Cardiac Anomalies.

PubMed

Kise, Hiroaki; Suzuki, Shoji; Hoshiai, Minako; Toda, Takako; Koizumi, Keiichi; Hasebe, Yohei; Kono, Yosuke; Honda, Yoshihiro; Kaga, Shigeaki; Sugita, Kanji

2015-12-01

The purpose of this study was to evaluate the potential of balloon-dilatable bilateral pulmonary artery banding (b-PAB) and its impact on the configuration of the pulmonary artery (PA). We have previously used balloon-dilatable b-PAB as first-stage palliation for patients with hypoplastic left heart syndrome (HLHS) and other complex cardiac anomalies. Two pliable tapes were placed around each branch of the PA and tightened with 7-0 polypropylene sutures in a manner that allowed for the subsequent adjustment of PA diameters. We retrospectively examined the adjustability of PA diameters by balloon dilation and the need for surgical PA angioplasty at later stages. From January 2010 to October 2013, we performed b-PAB in 8 patients, including 3 borderline cases between biventricular repair (BVR) and univentricular repair (UVR). The b-PAB procedures were performed at a median age of 6.5 days (range, 2-10 days). Balloon dilations were performed in 10 lesions in 4 patients. All of the procedures were performed safely. Two patients reached definite BVR. The remaining 6 patients underwent open palliative procedures with univentricular physiologies that resulted in 2 deaths unrelated to the initial b-PAB. In all but 1 of the patients, the PA configuration was properly maintained and did not require surgical pulmonary angioplasty. Balloon-dilatable b-PAB can be performed safely and prevents PA distortion at later stages. This technique should be considered for patients with complex cardiac anomalies if uncertainty exists regarding the optimal surgical strategy (BVR or UVR) in early infancy. © 2015, Wiley Periodicals, Inc.

Histopathology of aortic complications in bicuspid aortic valve versus Marfan syndrome: relevance for therapy?

PubMed

Grewal, Nimrat; Franken, Romy; Mulder, Barbara J M; Goumans, Marie-José; Lindeman, Johannes H N; Jongbloed, Monique R M; DeRuiter, Marco C; Klautz, Robert J M; Bogers, Ad J J C; Poelmann, Robert E; Groot, Adriana C Gittenberger-de

2016-05-01

Patients with bicuspid aortic valve (BAV) and patients with Marfan syndrome (MFS) are more prone to develop aortic dilation and dissection compared to persons with a tricuspid aortic valve (TAV). To elucidate potential common and distinct pathways of clinical relevance, we compared the histopathological substrates of aortopathy. Ascending aortic wall biopsies were divided in five groups: BAV (n = 36) and TAV (n = 23) without and with dilation and non-dilated MFS (n = 8). General histologic features, apoptosis, the expression of markers for vascular smooth muscle cell (VSMC) maturation, markers predictive for ascending aortic dilation in BAV, and expression of fibrillin-1 were investigated. Both MFS and BAV showed an altered distribution and decreased fibrillin-1 expression in the aorta and a significantly lower level of differentiated VSMC markers. Interestingly, markers predictive for aortic dilation in BAV were not expressed in the MFS aorta. The aorta in MFS was similar to the aorta in dilated TAV with regard to the presence of medial degeneration and apoptosis, while other markers for degeneration and aging like inflammation and progerin expression were low in MFS, comparable to BAV. Both MFS and BAV aortas have immature VSMCs, while MFS and TAV patients have a similar increased rate of medial degeneration. However, the mechanism leading to apoptosis is expected to be different, being fibrillin-1 mutation induced increased angiotensin-receptor-pathway signaling in MFS and cardiovascular aging and increased progerin in TAV. Our findings could explain why angiotensin inhibition is successful in MFS and less effective in TAV and BAV patients.

Long-term results of pneumatic dilatation for relapsing symptoms of achalasia after Heller myotomy.

PubMed

Legros, Ludivine; Ropert, Alain; Brochard, Charlène; Bouguen, Guillaume; Pagenault, Maël; Siproudhis, Laurent; Bretagne, Jean-François

2014-09-01

The aim of this study was to assess the efficacy and safety of pneumatic dilatation (PD) to treat symptom recurrence after Heller myotomy (HM). Consecutive patients receiving PD for relapsing symptoms following prior HM were included in this retrospective single-center study. Eckardt score ≤3 and/or ∆ Eckardt (difference between Eckardt score before and after dilatation) ≥3 defined the success of initial dilatation. Patients who maintained response longer than 2 months after initial dilatation were defined as short-term responders. Relapsers were offered further on-demand dilatation. Remission was defined as an Eckardt score ≤3 at the study endpoint. Kaplan-Meier survival curves were used to determine relapse rates. Eighteen patients (11 women, seven men) were included from January 2004 to January 2013. Ten patients had type I achalasia, and seven had type III, according to the Chicago classification. Thirty-nine PDs were performed (1.5 [1-2.25] per patient). All patients had short-term responses. The remission rate at the endpoint, after a median follow-up of 33 months, was 78%, but 44% were treated with on-demand PD during the follow-up interval. The proportions of patients without relapse and subsequent PD were 72% at 12 months, 65% at 24 and 36 months, and 49% at 48 months. No factors predictive of long-term response, particularly the type of achalasia, could be identified in this series. There were no perforations. In treating symptom recurrence following HM, PD was safe and effective over the long term when combined with subsequent PD. © 2014 John Wiley & Sons Ltd.

[Combination of the ureteral dilation catheter and balloon catheter under the ureteroscope in the treatment of male urethral stricture].

PubMed

Zhou, Yi; Li, Gong-hui; Yan, Jia-jun; Shen, Cong; Tang, Gui-hang; Xu, Gang

2016-01-01

To investigate the clinical application of the ureteral dilation catheter combined with the balloon catheter under the ureteroscope in the treatment of urethral stricture in men. Under the ureteroscope, 45 male patients with urethral stricture received placement of a zebra guide wire through the strictured urethra into the bladder and then a ureteral dilation catheter along the guide wire, followed by dilation of the urethra from F8 initially to F14 and F16. Again, the ureteroscope was used to determine the length of the strictured urethra, its distance to the external urethral orifice, and whether it was normally located. An F24 balloon catheter and then a metal urethral calibrator was used for the dilation of the strictured urethra. After removal of the F18-F22 urethral catheter at 8 weeks, the urinary flow rate was measured immediately and again at 3 months. All the operations were successfully performed without serious complications. The maximum urinary flow rate was (13.3-29.9) ml/s (mean [17.7 ± 3.2] ml/s) at the removal of the catheter and (15.2-30.8) ml/s (mean [19.8 ± 3.9] ml/s) at 3 months after it. Smooth urination was found in all the patients during the 6-24 months follow-up. The application of the ureteral dilation catheter combined with, the balloon catheter under the ureteroscope is a good option for the treatment of male urethral stricture for its advantages of uncomplicatedness, safety, effectiveness, few complications, less pain, high success rate, and repeatable operation.

Flicker-induced retinal arteriole dilation is reduced by ambient lighting.

PubMed

Noonan, Jonathan E; Dusting, Gregory J; Nguyen, Thanh T; Man, Ryan E K; Best, William J; Lamoureux, Ecosse L

2014-08-07

To investigate the impact of ambient room lighting on the magnitude of flicker light-induced retinal vasodilations in healthy individuals. Twenty healthy nonsmokers participated in a balanced 2 × 2 crossover study. Retinal vascular imaging was performed with the dynamic vessel analyzer under reduced or normal ambient lighting, then again after 20 minutes under the alternate condition. Baseline calibers of selected arteriole and venule segments were recorded in measurement units. Maximum percentage dilations from baseline during 20 seconds of luminance flicker were calculated from the mean of three measurement cycles. Within-subject differences were assessed by repeated measures analysis of variance with the assumption of no carryover effects and pairwise comparisons from the fitted model. Mean (SD) maximum arteriole dilations during flicker stimulation under reduced and normal ambient lighting were 4.8% (2.3%) and 4.1% (1.9%), respectively (P = 0.019). Maximum arteriole dilations were (mean ± 95% confidence interval) 0.7% ± 0.6% lower under normal ambient lighting compared with reduced lighting. Ambient lighting had no significant effect on maximum venular dilations during flicker stimulation or on the baseline calibers of arterioles or venules. Retinal arteriole dilation in response to luminance flicker stimulation is reduced under higher ambient lighting conditions. Reduced responses with higher ambient lighting may reflect reduced contrast between the ON and OFF flicker phases. Although it may not always be feasible to conduct studies under reduced lighting conditions, ambient lighting levels should be consistent to ensure that comparisons are valid. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Characterizing upper urinary tract dilation on ultrasound: a survey of North American pediatric radiologists' practices.

PubMed

Swenson, David W; Darge, Kassa; Ziniel, Sonja I; Chow, Jeanne S

2015-04-01

Radiologists commonly evaluate children first diagnosed with urinary tract dilation on prenatal ultrasound (US). To establish how North American pediatric radiologists define and report findings of urinary tract dilation on US. A web-based survey was sent to North American members of the Society for Pediatric Radiology (SPR) from January to February 2014. Reporting practices and interpretation of three image-based cases using free text were queried. Responses to close-ended questions were analyzed with descriptive statistics, while free-text responses to the three cases were categorized and analyzed as (1) using either descriptive terminology or an established numerical grading system and (2) as providing a quantitative term for the degree of dilation. Two hundred eighty-four pediatric radiologists answered the survey resulting in a response rate of 19.0%. There is a great variety in the terms used to describe urinary tract dilation with 66.2% using descriptive terminology, 35.6% using Society for Fetal Urology (SFU) grading system and 35.9% measuring anterior-posterior diameter (APD) of the renal pelvis. There is no consensus for a normal postnatal APD or the meaning of hydronephrosis. For the same images, descriptions vary widely in degree of severity ranging from normal to mild to severe. Similar variability exists among those using the SFU system. Ninety-seven percent say they believe a unified descriptive system would be helpful and 87.7% would use it if available. Pediatric radiologists do not have a standardized method for describing urinary tract dilation but have a great desire for such a system and would follow it if available.

Right heart dilatation in a fetus with an abnormal foramen ovale valve: an indicator of interatrial communication restriction.

PubMed

Lei, Wenjia; Fan, Miao; Wang, Meilian; Wang, Yu; Sun, Wei; Sun, Xue; Zhang, Ying

2018-05-02

Foramen ovale (FO) valve with a shape or motion abnormality is frequently detected during routine obstetric ultrasonic examinations. However, the hemodynamics mechanism of this entity remains unclear. The purpose of the study is to determine the relevance of interatrial communication restriction and resultant morphological modifications. We reviewed the echocardiographic records of fetuses with isolated abnormal FO valve evaluated between January of 2010 and december of 2016. The size (DFO) of the FO orifice, opening angle (α) of the FO valve, and dimensions of cardiac chambers, FO channel outlet (DOUT) and inferior vena cava (DIVC) were measured. We evaluated their (DFO, DOUT, α) relationships to the diameters of RA and DIVC. Five hundred and seventy normal fetuses were selected to establish the normal range of the DOUT/DIVC ratio so as to provide a criterion for restriction. An abnormal FO valve was identified in 89 fetuses without congenital heart disease, with restriction noted in 62 fetuses (45 fetuses with RA dilatation, 12 fetuses with RA and RV dilatation, and 5 fetuses with no RA dilatation). There were no significant correlations between RA/LA and DFO/DIVC, RA/ LA and α. RA/LA was negatively correlated with DOUT/DIVC (R2=0.97, p<0.01). For a fetus with an abnormal FO valve, right heart dilatation could be considered as an indicator of interatrial communication restriction, which could be assessed by evaluating the FO channel outlet. The degree of right atrium dilatation indicates the severity of the restriction.

Slow slip generated by dehydration reaction coupled with slip-induced dilatancy and thermal pressurization

NASA Astrophysics Data System (ADS)

Yamashita, Teruo; Schubnel, Alexandre

2016-10-01

Sustained slow slip, which is a distinctive feature of slow slip events (SSEs), is investigated theoretically, assuming a fault embedded within a fluid-saturated 1D thermo-poro-elastic medium. The object of study is specifically SSEs occurring at the down-dip edge of seismogenic zone in hot subduction zones, where mineral dehydrations (antigorite, lawsonite, chlorite, and glaucophane) are expected to occur near locations where deep slow slip events are observed. In the modeling, we introduce dehydration reactions, coupled with slip-induced dilatancy and thermal pressurization, and slip evolution is assumed to interact with fluid pressure change through Coulomb's frictional stress. Our calculations show that sustained slow slip events occur when the dehydration reaction is coupled with slip-induced dilatancy. Specifically, slow slip is favored by a low initial stress drop, an initial temperature of the medium close to that of the dehydration reaction equilibrium temperature, a low permeability, and overall negative volume change associated with the reaction (i.e., void space created by the reaction larger than the space occupied by the fluid released). Importantly, if we do not assume slip-induced dilatancy, slip is accelerated with time soon after the slip onset even if the dehydration reaction is assumed. This suggests that slow slip is sustained for a long time at hot subduction zones because dehydration reaction is coupled with slip-induced dilatancy. Such slip-induced dilatancy may occur at the down-dip edge of seismogenic zone at hot subduction zones because of repetitive occurrence of dehydration reaction there.

Eosinophilic esophagitis: dilate or medicate? A cost analysis model of the choice of initial therapy.

PubMed

Kavitt, R T; Penson, D F; Vaezi, M F

2014-07-01

Eosinophilic esophagitis (EoE) is an increasingly recognized clinical entity. The optimal initial treatment strategy in adults with EoE remains controversial. The aim of this study was to employ a decision analysis model to determine the less costly option between the two most commonly employed treatment strategies in EoE. We constructed a model for an index case of a patient with biopsy-proven EoE who continues to be symptomatic despite proton-pump inhibitor therapy. The following treatment strategies were included: (i) swallowed fluticasone inhaler (followed by esophagogastroduodenoscopy [EGD] with dilation if ineffective); and (ii) EGD with dilation (followed by swallowed fluticasone inhaler if ineffective). The time horizon was 1 year. The model focused on cost analysis of initial treatment strategies. The perspective of the healthcare payer was used. Sensitivity analyses were performed to assess the robustness of the model. For every patient whose symptoms improved or resolved with the strategy of fluticasone first followed by EGD, if necessary, it cost an average of $1078. Similarly, it cost an average of $1171 per patient if EGD with dilation was employed first. Sensitivity analyses indicated that initial treatment with fluticasone was the less costly strategy to improve dysphagia symptoms as long as the effectiveness of fluticasone remains at or above 0.62. Swallowed fluticasone inhaler (followed by EGD with dilation if necessary) is the more economical initial strategy when compared with EGD with dilation first. © 2012 Copyright the Authors. Journal compilation © 2012, Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.

Autosomal recessive atrial dilated cardiomyopathy with standstill evolution associated with mutation of Natriuretic Peptide Precursor A.

PubMed

Disertori, Marcello; Quintarelli, Silvia; Grasso, Maurizia; Pilotto, Andrea; Narula, Nupoor; Favalli, Valentina; Canclini, Camilla; Diegoli, Marta; Mazzola, Silvia; Marini, Massimiliano; Del Greco, Maurizio; Bonmassari, Roberto; Masè, Michela; Ravelli, Flavia; Specchia, Claudia; Arbustini, Eloisa

2013-02-01

Atrial dilatation and atrial standstill are etiologically heterogeneous phenotypes with poorly defined nosology. In 1983, we described 8-years follow-up of atrial dilatation with standstill evolution in 8 patients from 3 families. We later identified 5 additional patients with identical phenotypes: 1 member of the largest original family and 4 unrelated to the 3 original families. All families are from the same geographic area in Northeast Italy. We followed up the 13 patients for up to 37 years, extended the clinical investigation and monitoring to living relatives, and investigated the genetic basis of the disease. The disease was characterized by: (1) clinical onset in adulthood; (2) biatrial dilatation up to giant size; (3) early supraventricular arrhythmias with progressive loss of atrial electric activity to atrial standstill; (4) thromboembolic complications; and (5) stable, normal left ventricular function and New York Heart Association functional class during the long-term course of the disease. By linkage analysis, we mapped a locus at 1p36.22 containing the Natriuretic Peptide Precursor A gene. By sequencing Natriuretic Peptide Precursor A, we identified a homozygous missense mutation (p.Arg150Gln) in all living affected individuals of the 6 families. All patients showed low serum levels of atrial natriuretic peptide. Heterozygous mutation carriers were healthy and demonstrated normal levels of atrial natriuretic peptide. Autosomal recessive atrial dilated cardiomyopathy is a rare disease associated with homozygous mutation of the Natriuretic Peptide Precursor A gene and characterized by extreme atrial dilatation with standstill evolution, thromboembolic risk, preserved left ventricular function, and severely decreased levels of atrial natriuretic peptide.

The outcome of laparoscopic Heller myotomy for achalasia is not influenced by the degree of esophageal dilatation.

PubMed

Sweet, Matthew P; Nipomnick, Ian; Gasper, Warren J; Bagatelos, Karen; Ostroff, James W; Fisichella, Piero M; Way, Lawrence W; Patti, Marco G

2008-01-01

In the past, a Heller myotomy was considered to be ineffective in patients with achalasia and a markedly dilated or sigmoid-shaped esophagus. Esophagectomy was the standard treatment. The aims of this study were (a) to evaluate the results of laparoscopic Heller myotomy and Dor fundoplication in patients with achalasia and various degrees of esophageal dilatation; and (b) to assess the role of endoscopic dilatation in patients with postoperative dysphagia. One hundred and thirteen patients with esophageal achalasia were separated into four groups based on the maximal diameter of the esophageal lumen and the shape of the esophagus: group A, diameter<4.0 cm, 46 patients; group B, esophageal diameter 4.0-6.0 cm, 32 patients; group C, diameter>6.0 cm and straight axis, 23 patients; and group D, diameter>6.0 cm and sigmoid-shaped esophagus, 12 patients. All had a laparoscopic Heller myotomy and Dor fundoplication. The median length of follow-up was 45 months (range 7 months to 12.5 years). The postoperative recovery was similar among the four groups. Twenty-three patients (20%) had postoperative dilatations for dysphagia, and five patients (4%) required a second myotomy. Excellent or good results were obtained in 89% of group A and 91% of groups B, C, and D. None required an esophagectomy to maintain clinically adequate swallowing. These data show that (a) a laparoscopic Heller myotomy relieved dysphagia in most patients with achalasia, even when the esophagus was dilated; (b) about 20% of patients required additional treatment; (c) in the end, swallowing was good in 90%.

Quantitative analysis of iris changes after physiologic and pharmacologic mydriasis in a rural Chinese population.

PubMed

Zhang, Ye; Li, Si Zhen; Li, Lei; He, Ming Guang; Thomas, Ravi; Wang, Ning Li

2014-04-24

To estimate and compare the change in iris cross-sectional area (IA) and iris volume (IV) following physiologic and pharmacologic pupil dilation in primary angle closure suspects (PACS) and normal subjects. Anterior segment-optical coherence tomography (AS-OCT) measurements in light, dark, and following pharmacologic dilation were obtained on 186 PACS and 224 normal subjects examined during the 5-year follow-up of the Handan Eye Study. Iris cross-sectional area, IV, and other biometric parameters calculated using the Zhongshan angle assessment program in the right eyes of all subjects were analyzed. The mean IA and IV decreased in dark compared with light and after pharmacologic dilation in both PACS and normal eyes. This change was statistically significant in normal eyes: light versus pharmacologic dilation for IA (P = 0.038) and for IV, both light versus dark (P = 0.031) and light versus pharmacologic dilation (P = 0.012). A longer axial length (P = 0.028) and a greater change in pupil diameter (PD) (P < 0.001) were associated with a larger decrease of IA for the light to dark comparison. A diagnosis of normal eyes (P = 0.011), larger PD in dark (P = 0.001), and a larger change in PD (P = 0.001) were associated with a larger decrease of IV from light to dark. The differences in iris behavior between PACS and normal rural Chinese subjects following physiologic or pharmacologic pupillary dilation may help provide insights into the pathogenesis of angle closure. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Pupil-mimicry conditions trust in partners: moderation by oxytocin and group membership.

PubMed

Kret, Mariska E; De Dreu, Carsten K W

2017-03-15

Across species, oxytocin, an evolutionarily ancient neuropeptide, facilitates social communication by attuning individuals to conspecifics' social signals, fostering trust and bonding. The eyes have an important signalling function; and humans use their salient and communicative eyes to intentionally and unintentionally send social signals to others, by contracting the muscles around their eyes and pupils. In our earlier research, we observed that interaction partners with dilating pupils are trusted more than partners with constricting pupils. But over and beyond this effect, we found that the pupil sizes of partners synchronize and that when pupils synchronously dilate, trust is further boosted. Critically, this linkage between mimicry and trust was bound to interactions between ingroup members. The current study investigates whether these findings are modulated by oxytocin and sex of participant and partner. Using incentivized trust games with partners from ingroup and outgroup whose pupils dilated, remained static or constricted, this study replicates our earlier findings. It further reveals that (i) male participants withhold trust from partners with constricting pupils and extend trust to partners with dilating pupils, especially when given oxytocin rather than placebo; (ii) female participants trust partners with dilating pupils most, but this effect is blunted under oxytocin; (iii) under oxytocin rather than placebo, pupil dilation mimicry is weaker and pupil constriction mimicry stronger; and (iv) the link between pupil constriction mimicry and distrust observed under placebo disappears under oxytocin. We suggest that pupil-contingent trust is parochial and evolved in social species in and because of group life. © 2017 The Authors.

"Corkscrew stenosis": defining and preventing a complication of percutaneous dilatational tracheostomy.

PubMed

Jacobs, Jordan V; Hill, David A; Petersen, Scott R; Bremner, Ross M; Sue, Richard D; Smith, Michael A

2013-03-01

The short-term safety of percutaneous dilatational tracheostomy has been widely demonstrated. However, less is known about their long-term complications. Through an illustrative case series, we present and define "corkscrew stenosis," a type of tracheal stenosis uniquely associated with percutaneous dilatational tracheostomy. Patients treated at our institution for tracheal stenosis after percutaneous dilatational tracheostomy were reviewed. Demographic data including gender, age, history of presentation, lesion morphology, imaging, and management was collected and evaluated. The pathology of the stenosis and the strategies for prevention are presented. From January, 2008 through December 2011, 11 patients had tracheal stenosis after percutaneous dilatational tracheostomy. The mean age was 54 ± 17 years and 55% were male. The stenotic lesions were characterized by a corkscrew morphology at the stoma site with a mean distance of 2.3 ± 0.8 cm from the vocal cords. Images of these lesions demonstrated disruption and fracture of the proximal tracheal cartilages and displacement of the anterior tracheal wall into the tracheal lumen. The majority of our patients required tracheal resection for definitive repair. We suggest that a unique form of tracheal stenosis can result from percutaneous dilatational tracheostomy. We observed corkscrew stenosis to be located proximally, associated with fractured tracheal rings, and morphologically appearing as interdigitation of these fractured rings. Recognizing corkscrew stenosis, its unique mechanism of formation, and technical means of prevention may be important in advancing the long-term safety of this procedure for critically ill patients who require prolonged ventilatory support. Copyright © 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Dilatation of the Virchow-Robin spaces as an indicator of unilateral carotid artery stenosis: correlation with white matter lesions.

PubMed

Sahin, Neslin; Solak, Aynur; Genc, Berhan; Akpinar, Mehmet Besir

2015-07-01

Virchow-Robin space (VRS) dilatation is related to many pathologic conditions, mostly associated with vascular abnormalities. White matter lesions (WMLs) are commonly seen on brain magnetic resonance imaging (MRI) with advancing age and generally considered as potential markers for vascular disease. To investigate if asymmetric dilatation of VRSs and WMLs are associated with unilateral internal carotid artery stenosis (ICAS) and to test the relationship between dilated VRSs and common vascular risk factors. Twenty-nine patients (18 men, 11 women; mean age, 68.62 years) with unilateral ICAS (≥70% carotid stenosis) undergoing carotid endarterectomy were identified for this Health Insurance Portability and Accountability Act (HIPAA) compliant prospective study and assessed with brain MRI. Two experienced radiologists scored VRSs and WMLs and evaluated old infarcts, chronic lacunar infarcts, and cerebral atrophy. Asymmetry of WML and VRS scores between two cerebral hemispheres was assessed and associations between VRS scores, WML scores, and explanatory variables (e.g. age, sex, vascular risk factors, and atrophy) were tested. In this study, WMLs and basal ganglia VRSs were significantly greater in the unilateral hemisphere with ICA stenosis than contralateral hemisphere. Basal ganglia VRSs were associated with WMLs and internal cerebral atrophy. No association between the severity of VRSs and vascular risk factors was found. ICA stenosis may contribute as a factor in the development of WMLs and dilatation of VRSs by causing chronic hypoperfusion. VRS dilatation may be an additional MRI marker of ICAS. © The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Intermittent self-dilatation for urethral stricture disease in males.

PubMed

Jackson, Matthew J; Veeratterapillay, Rajan; Harding, Chris K; Dorkin, Trevor J

2014-12-19

Intermittent urethral self-dilatation is sometimes recommended to reduce the risk of recurrent urethral stricture. There is no consensus as to whether it is a clinically effective or cost-effective intervention in the management of this disease. The purpose of this review is to evaluate the clinical effectiveness and cost-effectiveness of intermittent self-dilatation after urethral stricture surgery in males compared to no intervention. We also compared different programmes of, and devices for, intermittent self-dilatation. . We searched the Cochrane Incontinence Group Specialised Register (searched 7 May 2014), CENTRAL (2014, Issue 4), MEDLINE (1 January 1946 to Week 3 April 2014), PREMEDLINE (covering 29 April 2014), EMBASE (1 January 1947 to Week 17 2014), CINAHL (31 December 1981 to 30 April 2014) OpenGrey (searched 6 May 2014), ClinicalTrials.gov (6 May 2014), WHO International Clinical Trials Registry Platform (6 May 2014), Current Controlled Trials (6 May 2014) and the reference lists of relevant articles. Randomised and quasi-randomised trials where one arm was a programme of intermittent self-dilatation for urethral stricture were identified. Studies were excluded if they were not randomised or quasi-randomised trials, or if they pertained to clean intermittent self-catheterisation for bladder emptying. Two authors screened the records for relevance and methodological quality. Data extraction was performed according to predetermined criteria using data extraction forms. Analyses were carried out in Cochrane Review Manager (RevMan 5). The primary outcomes were patient-reported symptoms and health-related quality of life, and risk of recurrence; secondary outcomes were adverse events, acceptability of the intervention to patients and cost-effectiveness. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Eleven trials were selected for inclusion in the review, including a total of 776 men. They were generally small; all were of poor quality and all were deemed to have high risk of bias. Performing intermittent self-dilatation versus not performing intermittent self-dilatation The data from six trials were heterogeneous, imprecise and had a high risk of bias, but indicated that recurrent urethral stricture was less likely in men who performed intermittent self-dilatation than men who did not perform intermittent self-dilatation (RR 0.70, 95% CI 0.48 to 1.00; very low quality evidence). Adverse events were generally poorly reported: two trials did not report adverse events and two trials reported adverse events only for the intervention group. Meta-analysis of the remaining two trials found no evidence of a difference between performing intermittent self-dilatation and not performing it (RR 0.60, 95% CI 0.11 to 3.26). No trials formally assessed acceptability, and no trials reported on patient-reported lower urinary tract symptoms, patient-reported health-related quality of life, or cost-effectiveness. One programme of intermittent self-dilatation versus another We identified two trials that compared different durations of intermittent self-dilatation, but data were not combined. One study could not draw robust conclusions owing to cross-over, protocol deviation, administrative error, post-hoc analysis and incomplete outcome reporting. The other study found no evidence of a difference between intermittent self-dilatation for six months versus for 12 months after optical urethrotomy (RR 0.67, 95% CI 0.12 to 3.64), although again the evidence is limited by the small sample size and risk of bias in the included study. Adverse events were reported narratively and were not stratified by group. No trials formally assessed acceptability, and no trials reported on patient-reported lower urinary tract symptoms, patient-reported health-related quality of life, or cost-effectiveness. One device for performing intermittent self-dilatation versus another Three trials compared one device for performing intermittent self-dilatation with another. Results from one trial at a high risk of bias were too uncertain to determine the effects of a low friction hydrophilic catheter and a standard polyvinyl chloride catheter on the risk of recurrent urethral stricture (RR 0.32, 95% CI 0.07 to 1.40). Similarly one study did not find evidence of a difference between one percent triamcinolone gel for lubricating the intermittent self-dilatation catheter versus water-based gel on risk of recurrent urethral stricture (RR 0.68, 95% CI 0.35 to 1.32). Two trials reported adverse events, but one did not provide sufficient detail for analysis. The other small study reported fewer instances of prostatitis, urethral bleeding or bacteriuria with a low friction hydrophilic catheter compared with a standard polyvinyl chloride catheter (RR 0.13, 95% CI 0.02 to 0.98). 'Happiness with the intervention' was assessed using a non-validated scale in one study, but no trials formally assessed patient-reported health-related quality of life or acceptability. No trials reported on patient-reported lower urinary tract symptoms or cost-effectiveness. GRADE quality assessment The evidence that intermittent self-dilatation reduces the risk of recurrent urethral stricture after surgical intervention was downgraded to 'very low' on the basis that the studies comprising the meta-analysis were deemed to have high risk of bias, and the data was imprecise and inconsistent. Insufficient evidence No trials provided cost-effectiveness data or used a validated patient-reported outcome measure, and adverse events were not reported rigorously. Acceptability of the intervention to patients has not been assessed quantitatively or qualitatively. Performing intermittent self-dilatation may confer a reduced risk of recurrent urethral stricture after endoscopic treatment. We have very little confidence in the estimate of the effect owing to the very low quality of the evidence. Evidence for other comparisons and outcomes is limited. Further research is required to determine whether the apparent benefit is sufficient to make the intervention worthwhile, and in whom.

Sublingual versus vaginal misoprostol for cervical dilatation 1 or 3 h prior to surgical abortion: a double-blinded RCT.

PubMed

Sääv, Ingrid; Kopp Kallner, Helena; Fiala, Christian; Gemzell-Danielsson, Kristina

2015-06-01

Can sublingual administration of misoprostol 1 h prior to vacuum aspiration be more effective than vaginal administration and as effective as either route three 3 h prior to surgery? Sublingually administered misoprostol is superior to vaginally administered misoprostol when given 1 h pre operatively, and it is as effective as after a three 3 h priming interval with either route of administration. Misoprostol reduces complications and morbidity when used for cervical priming prior to surgical dilatation and vacuum aspiration in first trimester pregnancy. Despite the widespread use and extensive studies, the optimal route of administration of misoprostol before surgical abortion remains to be defined. The optimal priming interval after vaginal and sublingual administration of 400 mcg misoprostol has been reported to be 3 h. A longer interval will not improve dilatation but will increase the risk for bleeding and expulsion of the uterine contents before surgical evacuation. The pharmacokinetic properties of misoprostol indicate that sublingual compared with vaginal administration of misoprostol may result in a more rapid cervical priming effect. Women were randomized to four treatment groups and received 400 mcg misoprostol sublingually, or vaginally, 1 or 3 h prior to surgery. The study was a double-blinded RCT with regard to route of misoprostol administration but not the timing interval. The primary outcome was baseline cervical dilatation after misoprostol priming. The study was conducted between June 2007 and March 2014 and 184 women aged 18 years or older were recruited. Women were recruited among nulliparous women undergoing elective surgical first trimester abortion. Exclusion criteria were any contraindication for misoprostol, untreated genital infection, previous history of surgery to the cervix, or abnormal pregnancy. Gestational age was established by endovaginal ultrasound examination. The trial was conducted in a university hospital outpatient clinic. The allocated medication (misoprostol and placebo) was self-administered 1 h or 3 h prior to surgery. All women received 2 tablets of 200 mcg misoprostol and 2 identical looking placebo tablets. Prophylactic pain medication, 100 mg oral diclofenac, was administered at the time of misoprostol. Side effects were recorded immediately before surgery and women were asked which administration route of administration they found most convenient and which they would have preferred. The exact priming time (from misoprostol administration to initiation of dilatation) and signs of bleeding prior to dilatation were recorded. Vacuum aspiration was performed under general anaesthesia according to clinical routine. Dilatation was performed using tapered Pratt-dilatators and the resistance of the cervix was assessed objectively using a tonometer. All surgery was performed by two investigators, experienced in using the tonometer. The cumulative force required to dilate the cervix was calculated by adding the peak force needed for each dilatator up to 9.7 mm. The time needed for surgery including cervical dilatation and vacuum aspiration, was recorded. Intra-operative blood loss was measured and any surgical complications noted. Six women were excluded retrospectively from the analysis. Multivariate analysis of the primary outcome baseline dilatation showed a significant influence on route of administration (P = 0.034, 95% confidence interval (CI) -2.202, -0.086) as well as the interaction variable between route of administration and total priming time (P = 0.042, 95% CI 0.00, 0.016), with the vaginal route becoming more effective with longer priming time. These factors also had a significant influence on the peak force (administration route P = 0.042, 95% CI 0.221, 12.427, interaction P = 0.049, 95% CI -0.089, 0.000) and cumulative force (administration route P = 0.023, 95% CI 3.142, 40.877, interaction P = 0.026, 95% CI -0.293, -0.019) used for dilatation. The total priming time had a significant influence on bleeding before surgery, with more women bleeding the longer the total priming time (P = 0.003, 95% CI 2.203, 49.706). For abdominal pain before surgery there was a significant influence of administration route (P = < 0.001 95% CI 0.028, 0.235) and the interaction variable between administration route and priming time (P = 0.003, 95% CI 2.005, 30.757) with more women in the sublingual group experiencing abdominal pain the longer the priming time. The groups did not differ regarding duration of surgery, amount of bleeding and rate of side effects, such as nausea and shivering. Women in our study preferred vaginal treatment, as they disliked the taste of the misoprostol tablets. Vaginal treatment was also perceived as quicker to administer (P = 0.0001). The cervical tissue has viscoelastic properties, i.e. tissue resistance to mechanical dilatation depends also on the rate at which dilatation is performed. The ideal measurement of dilatation force should therefore also record the rate and time of dilatation. To ensure comparability, only nulliparous women without prior cervical surgery were recruited. In addition, time of dilatation was recorded and did not differ between the groups, and it is therefore assumed that dilatation took place at approximately the same rate. A limitation is that the study was conducted over a long time period because there was only one tonometer, decreasing numbers of surgical abortions and the fact that the main author was on a rotation schedule. In addition, the study was not powered to detect differences in side effects. Priming with misoprostol is recommended prior to surgical abortion. The priming interval of misoprostol may be reduced to 1 h after sublingual administration but not after vaginal administration. The results of the present study will increase choice and flexibility in cervical priming. The Swedish research council (521-2009-2605), Swedish Council for Working Life and Social Research (1404/08), Stockholm County Council and Karolinska Institutet (ALF 2009-2012). All authors declare that they have no conflicts of interest. www.clincaltrials.gov, NCT 01933360. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Gastric dilatation-volvulus after splenic torsion in two dogs.

PubMed

Millis, D L; Nemzek, J; Riggs, C; Walshaw, R

1995-08-01

Two dogs developed gastric dilatation-volvulus 2 and 17 months, respectively, after splenectomy for treatment of splenic torsion. Splenic displacement and torsion may stretch the gastric ligaments, allowing increased mobility of the stomach. After splenectomy, an anatomic void may be created in the cranioventral part of the abdomen, contributing to the mobility of the stomach. Veterinarians treating dogs with isolated splenic torsion may wish to consider prophylactic gastropexy at splenectomy, to reduce the chance of future gastric dilatation-volvulus. Prophylactic gastropexy should be done only if the dog's hemodynamic status is stable enough to allow for performance of the additional surgery.

Improved test of time dilation in special relativity.

PubMed

Saathoff, G; Karpuk, S; Eisenbarth, U; Huber, G; Krohn, S; Muñoz Horta, R; Reinhardt, S; Schwalm, D; Wolf, A; Gwinner, G

2003-11-07

An improved test of time dilation in special relativity has been performed using laser spectroscopy on fast ions at the heavy-ion storage-ring TSR in Heidelberg. The Doppler-shifted frequencies of a two-level transition in 7Li+ ions at v=0.064c have been measured in the forward and backward direction to an accuracy of Deltanu/nu=1 x 10(-9) using collinear saturation spectroscopy. The result confirms the relativistic Doppler formula and sets a new limit of 2.2 x 10(-7) for deviations from the time dilation factor gamma(SR)=(1-v2/c2)(-1/2).

Reduction corporoplasty.

PubMed

Hakky, Tariq S; Martinez, Daniel; Yang, Christopher; Carrion, Rafael E

2015-01-01

Here we present the first video demonstration of reduction corporoplasty in the management of phallic disfigurement in a 17 year old man with a history sickle cell disease and priapism. Surgical management of aneurysmal dilation of the corpora has yet to be defined in the literature. We preformed bilateral elliptical incisions over the lateral corpora as management of aneurysmal dilation of the corpora to correct phallic disfigurement. The patient tolerated the procedure well and has resolution of his corporal disfigurement. Reduction corporoplasty using bilateral lateral elliptical incisions in the management of aneurysmal dilation of the corpora is a safe an feasible operation in the management of phallic disfigurement.

Balloon dilation of congenital supravalvular pulmonic stenosis in a dog.

PubMed

Treseder, Julia R; Jung, SeungWoo

2017-03-30

Percutaneous balloon valvuloplasty is considered the standard of care for treatment of valvular pulmonic stenosis, a common congenital defect in dogs. Supravalvular pulmonic stenosis is a rare form of pulmonic stenosis in dogs and standard treatment has not been established. Although, there have been reports of successful treatment of supravalvular pulmonic stenosis with surgical and stenting techniques, there have been no reports of balloon dilation to treat dogs with this condition. Here, a case of supravalvular pulmonic stenosis diagnosed echocardiographically and angiographically in which a significant reduction in pressure gradient was achieved with balloon dilation alone is presented.

[Dimenhydrinate overdosage in a 3(1/2) year-old-girl with dilative cardiomyopathy].

PubMed

Girisch, M; Hofbeck, M; Rauch, R; Apitz, C; Sieverding, L

2009-01-01

Dimenhydrinate overdosage in a 3(1/2) year-old-girl with dilative cardiomyopathy. Dimenhydrinate (Vomex(R)) is frequently used in the treatment of sickness and vomiting. The symptoms of overdosage present like an anticholinergic syndrome. We report on the clinical findings of an intoxication with dimenhydrinate in a 3(1/2) year-old-girl with functional dilative cardiomyopathy following a congenital left ventricular diverticle. Especially in small children, with the application of 40 mg suppositories once or twice per day the maximum dose of 3.75 mg/kgBW/d is achieved.

Prospective evaluation of laparoscopic-assisted gastropexy in dogs susceptible to gastric dilatation.

PubMed

Rawlings, Clarence A; Mahaffey, Mary B; Bement, Shannon; Canalis, Chanda

2002-12-01

To determine long-term outcome associated with laparoscopic-assisted gastropexy in prevention of gastric dilatation-volvulus (GDV) in susceptible dogs and to evaluate use of laparoscopy to correct GDV. Prospective study. 25 client-owned large-breed dogs. 23 dogs susceptible to GDV were referred as candidates for elective gastropexy. These dogs had a history of treatment for gastric dilatation, clinical signs of gastric dilatation, or family members with gastric dilatation. Laparoscopic-assisted gastropexy was performed. One year after surgery, abdominal ultrasonography was performed to evaluate the attachment of the stomach to the abdominal wall. Two dogs with GDV were also treated with laparoscopic-assisted derotation of the stomach and gastropexy. None of the dogs developed GDV during the year after gastropexy, and all 20 dogs examined ultrasonographically had an intact attachment. Another dog was euthanatized at 11.5 months for unrelated problems. Two dogs with GDV successfully underwent laparoscopic-assisted gastropexy after the stomach was repositioned. Laparoscopic-assisted gastropexy resulted in a persisting attachment between the stomach and abdominal wall, an absence of GDV development, and few complications. Dogs with a high probability for development of GDV should be considered candidates for minimally invasive gastropexy. Carefully selected dogs with GDV can be treated laparoscopically.

Dilatation by Soehendra stent retriever is feasible and effective in multiple deployment of metallic stents to malignant hilar biliary strictures.

PubMed

Kato, Hironari; Kawamoto, Hirofumi; Noma, Yasuhiro; Sonoyama, Takayuki; Tsutsumi, Koichiro; Fujii, Masakuni; Okada, Hiroyuki; Yamamoto, Kazuhide

2013-01-01

The endoscopic management of malignant hilar biliary strictures using multiple metallic stents (MS) is technically demanding, in the initial deployment of MS and the recovery from MS occlusion with deployment of multiple plastic stents (PS). We evaluated the outcomes of the application of a Soehendra stent retriever (SSR) as a dilator of intractable strictures. Fifty-nine patients with malignant hilar biliary strictures had multiple MS inserted using a partial stent-in-stent procedure. When we encountered intractable strictures, we adopted SSR to dilate the stricture and the interstice of the MS. We evaluated the success rate of MS or PS deployment after SSR application and procedural complications. Five of 59 patients (8%) were subjected to SSR application for the initial MS deployment. MS were successfully deployed in all of these patients (100%). MS occlusion was noted in 27 patients. We applied SSR to seven patients (26%) for the deployment of multiple PS after MS occlusion. In five patients (71%), successful PS deployment was achieved after the SSR application. No complications related to dilatation using SSR occurred in any patient. SSR proved to be a potent dilator of difficult strictures in the management of malignant hilar biliary strictures.

Update on second-trimester surgical abortion.

PubMed

Shaw, Kate A; Lerma, Klaira

2016-12-01

To review the recent literature on surgical second-trimester abortion, with specific attention to cervical preparation techniques. Confirming previous studies, a recent retrospective observational cohort study, including 54 911 abortions, estimated the total abortion-related complication rate to be 0.41% for second-trimester or later procedures. Cervical preparation is known to reduce risks associated with second-trimester dilation and evacuation (D&E). When considering adjuncts to osmotic dilators for cervical preparation prior to D&E after 16 weeks, both misoprostol and mifepristone are effective alone and in combination or as adjuncts to osmotic dilators. Misoprostol consistently has been shown to cause more pain and cramping than placebo, but is an effective adjunct to osmotic dilators after 16 weeks. Although mifepristone has fewer side-effects, at its current price, it may not be as cost-effective as misoprostol. Second-trimester abortion is safe. The use of mifepristone and misoprostol for second-trimester abortion has improved safety and efficacy of medical and surgical methods when used alone or in combination and as adjuncts to osmotic dilators. An important aspect of D&E, cervical preparation, is not a one-size-fits-all practice; the approach and methods are contingent on patient, provider and setting and should consider all the evidence-based options.

Stem-cell therapy for dilated cardiomyopathy: a pilot study evaluating retrograde coronary venous delivery.

PubMed

Pogue, B; Estrada, A H; Sosa-Samper, I; Maisenbacher, H W; Lamb, K E; Mincey, B D; Erger, K E; Conlon, T J

2013-07-01

To evaluate retrograde coronary venous stem-cell delivery for Dobermanns with dilated cardiomyopathy. Retrograde coronary venous delivery of adipose-derived mesenchymal stem cells transduced with tyrosine mutant adeno-associated virus 2 to express stromal-derived factor-1 was performed in Dobermanns with dilated cardiomyopathy. Cases were followed for 2 years and electrocardiograms (ECG), echocardiograms and Holter monitoring were performed. Delivery of cells was feasible in 15 of 15 dogs. One dog died following the development of ventricular fibrillation 24 hours after cell delivery. The remaining 14 dogs were discharged the following day without complications. Echocardiographic measurements of left ventricular size and function showed continued progression of disease. On the basis of Kaplan-Meier product limit estimates, median survival for dogs following stem-cell delivery was 620 days (range of 1-799 days). When including only the occult-dilated cardiomyopathy population and excluding those dogs already in congestive heart failure, median survival was 652 days (range of 46-799 days). Retrograde venous delivery of tyrosine mutant adeno-associated virus 2-stromal-derived factor-1 adipose-derived mesenchymal stem cells appears safe. Stem-cell therapy in dogs with occult-dilated cardiomyopathy does not appear to offer advantage compared to recently published survival data in similarly affected Dobermanns. © 2013 British Small Animal Veterinary Association.

Mitochondrial dysfunction in myocardium obtained from clinically normal dogs, clinically normal anesthetized dogs, and dogs with dilated cardiomyopathy.

PubMed

Sleeper, Meg M; Rosato, Bradley P; Bansal, Seema; Avadhani, Narayan G

2012-11-01

To compare mitochondrial complex I and complex IV activity in myocardial mitochondria of clinically normal dogs, clinically normal dogs exposed to inhalation anesthesia, and dogs affected with dilated cardiomyopathy. Myocardial samples obtained from 21 euthanized dogs (6 clinically normal [control] dogs, 5 clinically normal dogs subjected to inhalation anesthesia with isoflurane prior to euthanasia, 5 dogs with juvenile-onset dilated cardiomyopathy, and 5 dogs with adult-onset dilated cardiomyopathy). Activity of mitochondrial complex I and complex IV was assayed spectrophotometrically in isolated mitochondria from left ventricular tissue obtained from the 4 groups of dogs. Activity of complex I and complex IV was significantly decreased in anesthetized dogs, compared with activities in the control dogs and dogs with juvenile-onset or adult-onset dilated cardiomyopathy. Inhalation anesthesia disrupted the electron transport chain in the dogs, which potentially led to an outburst of reactive oxygen species that caused mitochondrial dysfunction. Inhalation anesthesia depressed mitochondrial function in dogs, similar to results reported in other species. This effect is important to consider when anesthetizing animals with myocardial disease and suggested that antioxidant treatments may be beneficial in some animals. Additionally, this effect should be considered when designing studies in which mitochondrial enzyme activity will be measured. Additional studies that include a larger number of animals are warranted.

Canine dilated cardiomyopathy: a retrospective study of signalment, presentation and clinical findings in 369 cases.

PubMed

Martin, M W S; Stafford Johnson, M J; Celona, B

2009-01-01

To review the clinical and diagnostic findings and survival of dilated cardiomyopathy from a large population of dogs in England. A retrospective study of the case records of dogs with dilated cardiomyopathy collected between January 1993 and May 2006. There were 369 dogs with dilated cardiomyopathy of which all were pure-bred dogs except for four. The most commonly affected breeds were dobermanns and boxers. Over 95 per cent of dogs weighed more than 15 kg and 73 per cent were male. The median duration of signs before referral was three weeks with 65 per cent presenting in stage 3 heart failure. The most common signs were breathlessness (67 per cent) and coughing (64 per cent). The majority of dogs (89 per cent) had an arrhythmia at presentation and 74 per cent of dogs had radiographic signs of pulmonary oedema or pleural effusion. The median survival time was 19 weeks. Dilated cardiomyopathy occurs primarily in medium to large breed pure-bred dogs, and males are more frequently affected than females. The duration of clinical signs before referral is often short and the survival times are poor. Greater awareness of affected breeds, clinical signs and diagnostic findings may help in early recognition of this disease which often has a short clinical phase.

Echodense spinal subarachnoid space in neonates with progressive ventricular dilatation: a marker of noncommunicating hydrocephalus.

PubMed

Rudas, G; Almássy, Z; Papp, B; Varga, E; Méder, U; Taylor, G A

1998-10-01

Our purpose was to evaluate the frequency and clinical significance of echogenic debris in the spinal subarachnoid space of neonates at risk for progressive ventricular dilatation. Spinal sonography was performed on 15 neonates with severe intracranial hemorrhage (n = 10) or bacterial meningitis (n = 5). Spinal sonography also was performed on 16 control neonates. Images were analyzed for the presence and location of echogeric debris within the thoracolumbar subarachnoid space. Lumbar punctures were performed on all 31 neonates, and CSF was analyzed for cell count and protein content. Ten of 15 neonates required ventricular drainage procedures. Progressive ventricular dilatation occurred in 11 of 15 neonates with intracranial hemorrhage or meningitis. Echogenic debris was present in the thoracolumbar subarachnoid space on spinal sonography in every neonate with progressive ventricular dilatation compared with none of the 16 control neonates (p < .0001 by chi-square analysis). In addition, the 11 neonates with echogenic subarachnoid space had significantly higher protein and RBC contents in the lumbar CSF (p < .04). Echogenic subarachnoid space revealed by sonography is associated with progressive ventricular dilatation after severe intracranial hemorrhage or bacterial meningitis and is caused by high protein and RBC contents in the subarachnoid space. This finding may be helpful in identifying neonates who will not benefit from serial lumbar punctures for treatment of hydrocephalus.

High prevalence of myocardial monoclonal antimyosin antibody uptake in patients with chronic idiopathic dilated cardiomyopathy

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

Obrador, D.; Ballester, M.; Carrio, I.

1989-05-01

Monoclonal antimyosin antibody studies were undertaken to assess the presence of myocardial uptake in patients with chronic idiopathic dilated cardiomyopathy. Three groups were studied: 17 patients with chronic (greater than 12 months) idiopathic dilated cardiomyopathy, 12 patients with a large, poorly contracting left ventricle not due to dilated cardiomyopathy (control patients) and 8 normal individuals. The patients in the cardiomyopathy and control groups showed a similar degree of clinical and functional impairment. Imaging was undertaken 48 h after antimyosin injection. The heart/lung ratio of antimyosin uptake was used to assess the results. The mean ratio in the cardiomyopathy group wasmore » 1.83 +/- 0.36 (range 1.40 to 2.80), a value significantly higher than that obtained in the control patients without cardiomyopathy (mean 1.46 +/- 0.04, range 1.38 to 1.50) or normal subjects (mean 1.46 +/- 0.13, range 1.31 to 1.6) (p less than 0.01). No difference in the ratio was noted between the normal subjects and control patients. Abnormal antimyosin uptake was seen in 12 (70%) of the 17 patients with cardiomyopathy and in only 1 (8%) of the 12 control patients. Positive monoclonal antimyosin antibody studies are highly prevalent in chronic idiopathic dilated cardiomyopathy.« less

[Two cases of afferent loop syndrome caused by obstruction at the jejuno-jejunostomy site in the Roux-en-Y loop that were successfully treated by endoscopic balloon dilatation].

PubMed

Yasuda, Atsushi; Imamoto, Haruhiko; Furukawa, Hiroshi; Imano, Motohiro; Yasuda, Takushi; Okuno, Kiyokata

2014-11-01

We report 2 rare cases of afferent loop syndrome caused by obstruction at the jejuno-jejunostomy site in the Roux-en-Y loop after total gastrectomy, which was successfully treated by endoscopic balloon dilatation of the anastomotic stenosis. Case 1: A 62-year-old woman presented with malaise and lower abdominal distension 6 months after laparoscopy-assisted total gastrectomy with Roux-en-Y reconstruction. She was diagnosed with afferent loop syndrome; CT imaging indicated marked dilatation of the afferent loop, with membranous obstruction at the jejuno-jejunostomy site in the Roux-en-Y loop. Although almost complete occlusion was noted at the jejuno-jejunostomy site, the obstruction was successfully relieved by endoscopic balloon dilation using TandemTM XL Triple Lumen ERCP Cannula (Boston Scientific)®. Case 2: A 70-year-old man presented with malaise and lower abdominal distension 3 years after laparoscopy-assisted total gastrectomy with Roux-en-Y reconstruction. He was diagnosed with afferent loop syndrome; CT imaging indicated complete obstruction at the jejuno-jejunostomy site in the Roux-en-Y loop. As in case 1, the obstruction was successfully treated by endoscopic balloon dilatation of the occluded anastomosis.

Exact reconstruction with directional wavelets on the sphere

NASA Astrophysics Data System (ADS)

Wiaux, Y.; McEwen, J. D.; Vandergheynst, P.; Blanc, O.

2008-08-01

A new formalism is derived for the analysis and exact reconstruction of band-limited signals on the sphere with directional wavelets. It represents an evolution of a previously developed wavelet formalism developed by Antoine & Vandergheynst and Wiaux et al. The translations of the wavelets at any point on the sphere and their proper rotations are still defined through the continuous three-dimensional rotations. The dilations of the wavelets are directly defined in harmonic space through a new kernel dilation, which is a modification of an existing harmonic dilation. A family of factorized steerable functions with compact harmonic support which are suitable for this kernel dilation are first identified. A scale-discretized wavelet formalism is then derived, relying on this dilation. The discrete nature of the analysis scales allows the exact reconstruction of band-limited signals. A corresponding exact multi-resolution algorithm is finally described and an implementation is tested. The formalism is of interest notably for the denoising or the deconvolution of signals on the sphere with a sparse expansion in wavelets. In astrophysics, it finds a particular application for the identification of localized directional features in the cosmic microwave background data, such as the imprint of topological defects, in particular, cosmic strings, and for their reconstruction after separation from the other signal components.

[Caroli's disease: congenital cystic and segmentary dilatation of the intrahepatic bile ducts].

PubMed

Serra, C A; Recalde, E B; Martellotto, G I

1987-01-01

Congenital cystic segmentary dilatation of the intrahepatic biliary ducts is a rare disease. Although several cases has been described in medical literature, its occurrence such as it was originally referred is exceptional. Some cases coexist with congenital hepatic fibrosis and portal hypertension. A characteristic phenomenon is the formation of stones and canalicular infection. In this article, three cases of Caroli disease (females, 57, 53 and 58 years old) are described. Case n 1 was a complex malformation including: a) cystic and segmentary dilatations of the intrahepatic biliar ducts; b) intra and extrahepatic lithiasis and recurrent infections; c) fusion of the choledocus and gallbladder in a common sac; d) hepatic cavernosus hemangioma and a supernumerarious lobe. Case n 2 showed: a) cystic and segmentary dilatation of the intrahepatic biliar ducts; b) portal fibrosis; c) polycystic kidneys; d) portal hypertension. Case n 3 showed: a) cystic and segmentary dilatation of the intrahepatic biliar ducts; b) portal fibrosis; c) polycystic kidneys and spleen; d) portal hypertension. Prognostic of this patients is variable and depends on the recurrent infections and the coexistence of other malformations which are frequently severe. Surgery is the only treatment for the disease although there are no definite conclusions concerning the long-term results.

Impaired flow-induced dilation in mesenteric resistance arteries from mice lacking vimentin.

PubMed Central

Henrion, D; Terzi, F; Matrougui, K; Duriez, M; Boulanger, C M; Colucci-Guyon, E; Babinet, C; Briand, P; Friedlander, G; Poitevin, P; Lévy, B I

1997-01-01

The intermediate filament vimentin might play a key role in vascular resistance to mechanical stress. We investigated the responses to pressure (tensile stress) and flow (shear stress) of mesenteric resistance arteries perfused in vitro from vimentin knockout mice. Arteries were isolated from homozygous (Vim-/-, n = 14) or heterozygous vimentin-null mice (Vim+/-, n = 5) and from wild-type littermates (Vim+/+, n = 9). Passive arterial diameter (175+/-15 micron in Vim+/+ at 100 mmHg) and myogenic tone were not affected by the absence of vimentin. Flow-induced (0-150 microl/min) dilation (e. g., 19+/-3 micron dilation at 150 mmHg in Vim+/+) was significantly attenuated in Vim-/- mice (13+/-2 micron dilation, P < 0.01). Acute blockade of nitric oxide synthesis (NG-nitro- L-arginine, 10 microM) significantly decreased flow-induced dilation in both groups, whereas acute blockade of prostaglandin synthesis (indomethacin, 10 microM) had no significant effect. Mean blood pressure, in vivo mesenteric blood flow and diameter, and mesenteric artery media thickness or media to lumen ratio were not affected by the absence of vimentin. Thus, the absence of vimentin decreased selectively the response of resistance arteries to flow, suggesting a role for vimentin in the mechanotransduction of shear stress. PMID:9389758

Slip and Dilation Tendency Analysis of the Patua Geothermal Area

DOE Data Explorer

Faulds, James E.

2013-12-31

Critically stressed fault segments have a relatively high likelihood of acting as fluid flow conduits (Sibson, 1994). As such, the tendency of a fault segment to slip (slip tendency; Ts; Morris et al., 1996) or to dilate (dilation tendency; Td; Ferrill et al., 1999) provides an indication of which faults or fault segments within a geothermal system are critically stressed and therefore likely to transmit geothermal fluids. The slip tendency of a surface is defined by the ratio of shear stress to normal stress on that surface: Ts = τ / σn (Morris et al., 1996). Dilation tendency is defined by the stress acting normal to a given surface: Td = (σ1-σn) / (σ1-σ3) (Ferrill et al., 1999). Slip and dilation were calculated using 3DStress (Southwest Research Institute). Slip and dilation tendency are both unitless ratios of the resolved stresses applied to the fault plane by ambient stress conditions. Values range from a maximum of 1, a fault plane ideally oriented to slip or dilate under ambient stress conditions to zero, a fault plane with no potential to slip or dilate. Slip and dilation tendency values were calculated for each fault in the focus study areas at, McGinness Hills, Neal Hot Springs, Patua, Salt Wells, San Emidio, and Tuscarora on fault traces. As dip is not well constrained or unknown for many faults mapped in within these we made these calculations using the dip for each fault that would yield the maximum slip tendency or dilation tendency. As such, these results should be viewed as maximum tendency of each fault to slip or dilate. The resulting along-fault and fault-to-fault variation in slip or dilation potential is a proxy for along fault and fault-to-fault variation in fluid flow conduit potential. Stress Magnitudes and directions Stress field variation within each focus area was approximated based on regional published data and the world stress database (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes, 2010; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012; Moeck et al., 2010; Moos and Ronne, 2010 and Reinecker et al., 2005) as well as local stress information if applicable. For faults within these focus systems we applied either a normal faulting stress regime where the vertical stress (sv) is larger than the maximum horizontal stress (shmax) which is larger than the minimum horizontal stress (sv>shmax>shmin) or strike-slip faulting stress regime where the maximum horizontal stress (shmax) is larger than the vertical stress (sv) which is larger than the minimum horizontal stress (shmax >sv>shmin) depending on the general tectonic province of the system. Based on visual inspection of the limited stress magnitude data in the Great Basin we used magnitudes such that shmin/shmax = .527 and shmin/sv= .46, which are consistent with complete and partial stress field determinations from Desert Peak, Coso, the Fallon area and Dixie valley (Hickman et al., 2000; Hickman et al., 1998 Robertson-Tait et al., 2004; Hickman and Davatzes, 2011; Davatzes and Hickman, 2006; Blake and Davatzes 2011; Blake and Davatzes, 2012). Slip and dilation tendency analysis for the Patua geothermal system was calculated based on faults mapped in the Hazen Quadrangle (Faulds et al., 2011). Patua lies near the margin between the Basin and Range province, which is characterized by west-northwest directed extension and the Walker Lane province, characterized by west-northwest directed dextral shear. As such, the Patua area likely has been affected by tectonic stress associated with either or both of stress regimes over geologic time. In order to characterize this stress variation we calculated slip tendency at Patua for both normal faulting and strike slip faulting stress regimes. Based on examination of regional and local stress data (as explained above) we applied at shmin direction of 105 to Patua. Whether the vertical stress (sv) magnitude is larger than ...

Hypnoanalgesia for Dilatation and Curettage Pain Control

PubMed Central

Fathi, Mehdi; Aziz Mohammadi, Susan; Moslemifar, Mehdi; Kamali, Kurosh; Joudi, Marjan; Sabri Benhangi, Azam; Mohaddes, Mojtaba; Joudi, Mona; Mohajeri, Mozhgan

2017-01-01

There are many acceptable approaches ranging from light to moderate intravenous sedation or analgesic drugs that are used to provide pain control in dilatation and curettage. We report the use of hypnosis as a nonpharmacologic approach to control pain in this manner. PMID:28824863

Long-term outcome of conventional endotracheal tube balloon dilation of tracheal stenosis in a dog.

PubMed

Kahane, Nili; Segev, Gilad

2014-01-01

This report describes a successful dilation of tracheal stenosis in a 16-year-old dog using a conventional endotracheal tube balloon. This technique should be considered as palliative treatment when owners decline other therapeutic options.

Ventricular dilation and electrical dyssynchrony synergistically increase regional mechanical nonuniformity but not mechanical dyssynchrony: a computational model.

PubMed

Kerckhoffs, Roy C P; Omens, Jeffrey H; McCulloch, Andrew D; Mulligan, Lawrence J

2010-07-01

Heart failure (HF) in combination with mechanical dyssynchrony is associated with a high mortality rate. To quantify contractile dysfunction in patients with HF, investigators have proposed several indices of mechanical dyssynchrony, including percentile range of time to peak shortening (WTpeak), circumferential uniformity ratio estimate (CURE), and internal stretch fraction (ISF). The goal of this study was to compare the sensitivity of these indices to 4 major abnormalities responsible for cardiac dysfunction in dyssynchronous HF: dilation, negative inotropy, negative lusitropy, and dyssynchronous activation. All combinations of these 4 major abnormalities were included in 3D computational models of ventricular electromechanics. Compared with a nonfailing heart model, ventricles were dilated, inotropy was reduced, twitch duration was prolonged, and activation sequence was changed from normal to left bundle branch block. In the nonfailing heart, CURE, ISF, and WTpeak were 0.97+/-0.004, 0.010+/-0.002, and 78+/-1 milliseconds, respectively. With dilation alone, CURE decreased 2.0+/-0.07%, ISF increased 58+/-47%, and WTpeak increased 31+/-3%. With dyssynchronous activation alone, CURE decreased 15+/-0.6%, ISF increased 14-fold (+/-3), and WTpeak increased 121+/-4%. With the combination of dilation and dyssynchronous activation, CURE decreased 23+/-0.8%, ISF increased 20-fold (+/-5), and WTpeak increased 147+/-5%. Dilation and left bundle branch block combined synergistically decreased regional cardiac function. CURE and ISF were sensitive to this combination, but WTpeak was not. CURE and ISF also reflected the relative nonuniform distribution of regional work better than WTpeak. These findings might explain why CURE and ISF are better predictors of reverse remodeling in cardiac resynchronization therapy.

Pediatric lymphangiectasia: an imaging spectrum.

PubMed

Malone, Ladonna J; Fenton, Laura Z; Weinman, Jason P; Anagnost, Miran R; Browne, Lorna P

2015-04-01

Lymphangiectasia is a rarely encountered lymphatic dysplasia characterized by lymphatic dilation without proliferation. Although it can occur anywhere, the most common locations are the central conducting lymphatics and the pulmonary and intestinal lymphatic networks. Recent advances in lymphatic interventions have resulted in an increased reliance on imaging to characterize patterns of disease. To describe the patient populations, underlying conditions, and imaging features of lymphangiectasia encountered at a tertiary pediatric institution over a 10-year period and correlate these with pathology and patient outcomes. We retrospectively reviewed the pathology database from 2002 to 2012 to identify patients with pathologically or surgically proven lymphangiectasia who had undergone cross-sectional imaging. Medical records were reviewed for patient demographics, underlying conditions, treatment and outcome. Thirteen children were identified, ranging in age from 1 month to 16 years. Five had pulmonary lymphangiectasia, four intestinal and four diffuse involvement. Pulmonary imaging findings include diffuse or segmental interlobular septal thickening, pleural effusions and dilated mediastinal lymphatics. Intestinal imaging findings include focal or diffuse bowel wall thickening with central lymphatic dilation. Diffuse involvement included dilation of the central lymphatics and involvement of more than one organ system. Children with infantile presentation and diffuse pulmonary, intestinal or diffuse lymphatic abnormalities had a high mortality rate. Children with later presentations and segmental involvement demonstrated clinical improvement with occasional regression of disease. Three children with dilated central lymphatics on imaging underwent successful lymphatic duct ligation procedures with improved clinical course. Lymphangiectasia is a complex disorder with a spectrum of presentations, imaging appearances, treatments and outcomes. Cross-sectional imaging techniques distinguish segmental involvement of a single system (pulmonary or intestinal) from diffuse disease and may show dilated central conducting lymphatics, which may benefit from interventions such as ligation or occlusion.

Pathogenesis of aortic dilatation in mucopolysaccharidosis VII mice may involve complement activation

PubMed Central

Baldo, Guilherme; Wu, Susan; Howe, Ruth A.; Ramamoothy, Meera; Knutsen, Russell H.; Fang, Jiali; Mecham, Robert P.; Liu, Yuli; Wu, Xiaobo; Atkinson, John P.; Ponder, Katherine P.

2012-01-01

Mucopolysaccharidosis VII (MPS VII) is due to mutations within the gene encoding the lysosomal enzyme β-glucuronidase, and results in the accumulation of glycosaminoglycans. MPS VII causes aortic dilatation and elastin fragmentation, which is associated with upregulation of the elastases cathepsin S (CtsS) and matrix metalloproteinase 12 (MMP12). To test the role of these enzymes, MPS VII mice were crossed with mice deficient in CtsS or MMP12, and the effect upon aortic dilatation was determined. CtsS deficiency did not protect against aortic dilatation in MPS VII mice, but also failed to prevent an upregulation of cathepsin enzyme activity. Further analysis with substrates and inhibitors specific for particular cathepsins suggests that this enzyme activity was due to CtsB, which could contribute to elastin fragmentation. Similarly, MMP12 deficiency and deficiency of both MMP12 and CtsS could not prevent aortic dilatation in MPS VII mice. Microarray and reverse-transcriptase real-time PCR were performed to look for upregulation of other elastases. This demonstrated that mRNA for complement component D was elevated in MPS VII mice, while immunostaining demonstrated high levels of complement component C3 on surfaces within the aortic media. Finally, we demonstrate that neonatal intravenous injection of a retroviral vector encoding β-glucuronidase reduced aortic dilatation. We conclude that neither CtsS nor MMP12 are necessary for elastin fragmentation in MPS VII mouse aorta, and propose that CtsB and/or complement component D may be involved. Complement may be activated by the GAGs that accumulate, and may play a role in signal transduction pathways that upregulate elastases. PMID:21944884

The eye as a window to the listening brain: neural correlates of pupil size as a measure of cognitive listening load.

PubMed

Zekveld, Adriana A; Heslenfeld, Dirk J; Johnsrude, Ingrid S; Versfeld, Niek J; Kramer, Sophia E

2014-11-01

An important aspect of hearing is the degree to which listeners have to deploy effort to understand speech. One promising measure of listening effort is task-evoked pupil dilation. Here, we use functional magnetic resonance imaging (fMRI) to identify the neural correlates of pupil dilation during comprehension of degraded spoken sentences in 17 normal-hearing listeners. Subjects listened to sentences degraded in three different ways: the target female speech was masked by fluctuating noise, by speech from a single male speaker, or the target speech was noise-vocoded. The degree of degradation was individually adapted such that 50% or 84% of the sentences were intelligible. Control conditions included clear speech in quiet, and silent trials. The peak pupil dilation was larger for the 50% compared to the 84% intelligibility condition, and largest for speech masked by the single-talker masker, followed by speech masked by fluctuating noise, and smallest for noise-vocoded speech. Activation in the bilateral superior temporal gyrus (STG) showed the same pattern, with most extensive activation for speech masked by the single-talker masker. Larger peak pupil dilation was associated with more activation in the bilateral STG, bilateral ventral and dorsal anterior cingulate cortex and several frontal brain areas. A subset of the temporal region sensitive to pupil dilation was also sensitive to speech intelligibility and degradation type. These results show that pupil dilation during speech perception in challenging conditions reflects both auditory and cognitive processes that are recruited to cope with degraded speech and the need to segregate target speech from interfering sounds. Copyright © 2014 Elsevier Inc. All rights reserved.

Interaction of pepsin-[C16mim]Br system: interfacial dilational rheology and conformational studies.

PubMed

Huang, Tian; Cao, Chong; Liu, Zi-lin; Li, Yang; Du, Feng-pei

2014-09-21

The interfacial rheological property is closely related to the stabilities of foams and emulsions, yet there have been limited studies on the interaction between proteins with ionic liquid-type imidazolium surfactants at the decane-water interface as well as in the bulk. Herein, we investigated the interfacial and bulk properties of pepsin (PEP) and an ionic liquid (IL), 1-hexadecyl-3-methylimidazolium bromide, [C(16)mim]Br. The interfacial pressure and dilational rheology studies were performed to describe the formation of [C(16)mim]Br-pepsin complexes. The influence of the oscillating frequency and the bulk concentration of [C(16)mim]Br on the dilational properties were explored. The conformational changes were studied by monitoring the fluorescence and far UV-CD spectra. The results reveal that the globular structure of pepsin is one of the decisive factors controlling the nature of the interfacial film. The monotonous increase in the dilational elastic modulus of pepsin-[C(16)mim]Br solutions with the surface age indicates that no loops and tails had formed. Interestingly, with an increase in the concentration of [C(16)mim]Br, the εd-c curve first passes through a plateau value due to steric hindrance and the electrostatic barrier of already absorbed tenacious pepsin-[C(16)mim]Br complexes. With the further addition of [C(16)mim]Br, the remarkable decrease in dilational elastic modulus indicates that the compact structure is destroyed gradually. The results of the fluorescence spectra and far UV-CD spectra confirm that [C(16)mim]Br did not produce perceptible changes in pepsin at the concentrations studied in the dilational experiment. Possible schematic programs of the pepsin-[C(16)mim]Br interaction model at the interface and in bulk phase are proposed.

Persistent recovery of normal left ventricular function and dimension in idiopathic dilated cardiomyopathy during long‐term follow‐up: does real healing exist?

PubMed

Merlo, Marco; Stolfo, Davide; Anzini, Marco; Negri, Francesco; Pinamonti, Bruno; Barbati, Giulia; Ramani, Federica; Lenarda, Andrea Di; Sinagra, Gianfranco

2015-01-13

An important number of patients with idiopathic dilated cardiomyopathy have dramatically improved left ventricular function with optimal treatment; however, little is known about the evolution and long-term outcome of this subgroup, which shows apparent healing. This study assesses whether real healing actually exists in dilated cardiomyopathy. Persistent apparent healing was evaluated among 408 patients with dilated cardiomyopathy receiving tailored medical treatment and followed over the very long-term. Persistent apparent healing was defined as left ventricular ejection fraction ≥50% and indexed left ventricular end-diastolic diameter ≤33 mm/m(2) at both mid-term (19±4 months) and long-term (103±9 months) follow-up. At mid-term, 63 of 408 patients (15%) were apparently healed; 38 (60%; 9%of the whole population) showed persistent apparent healing at long-term evaluation. No predictors of persistent apparent healing were found. Patients with persistent apparent healing showed better heart transplant–free survival at very long-term follow-up (95% versus 71%; P=0.014) compared with nonpersistently normalized patients. Nevertheless, in the very longterm, 37% of this subgroup experienced deterioration of left ventricular systolic function, and 5% died or had heart transplantation. Persistent long-term apparent healing was evident in a remarkable proportion of dilated cardiomyopathy patients receiving optimal medical treatment and was associated with stable normalization of main clinical and laboratory features. This condition can be characterized by a decline of left ventricular function over the very long term, highlighting the relevance of serial nd individualized follow-up in all patients with dilated cardiomyopathy, especially considering the absence of predictors for longterm apparent healing.

Nitrosative stress uncovers potent β2-adrenergic receptor-linked vasodilation further enhanced by blockade of clathrin endosome formation.

PubMed

Frame, Mary D; Dewar, Anthony M; Calizo, Rhodora C; Qifti, Androniqi; Scarlata, Suzanne F

2018-06-01

This study investigated the effect of sodium nitroprusside (SNP) preexposure on vasodilation via the β-adrenergic receptor (BAR) system. SNP was used as a nitrosative/oxidative proinflammatory insult. Small arterioles were visualized by intravital microscopy in the hamster cheek pouch tissue (isoflurane, n = 45). Control dilation to isoproterenol (EC 50 : 10 -7 mol/l) became biphasic as a function of concentration after 2 min of exposure to SNP (10 -4 M), with increased potency at picomolar dilation uncovered and decreased efficacy at the micromolar dilation. Control dilation to curcumin was likewise altered after SNP, but only the increased potency at a low dose was uncovered, whereas micromolar dilation was eliminated. The picomolar dilations were blocked by the potent BAR-2 inverse agonist carazolol (10 -9 mol/l). Dynamin inhibition with dynasore mimicked this effect, suggesting that SNP preexposure prevented BAR agonist internalization. Using HeLa cells transfected with BAR-2 tagged with monomeric red fluorescent protein, exposure to 10 -8 -10 -6 mol/l curcumin resulted in internalization and colocalization of BAR-2 and curcumin (FRET) that was prevented by oxidative stress (10 -3 mol/l CoCl 2 ), supporting that stress prevented internalization of the BAR agonist with the micromolar agonist. This study presents novel data supporting that distinct pools of BARs are differentially available after inflammatory insult. NEW & NOTEWORTHY Preexposure to an oxidative/nitrosative proinflammatory insult provides a "protective preconditioning" against future oxidative damage. We examined immediate vasoactive and molecular consequences of a brief preexposure via β-adrenergic receptor signaling in small arterioles. Blocked receptor internalization with elevated reactive oxygen levels coincides with a significant and unexpected vasodilation to β-adrenergic agonists at picomolar doses.

Early endoscopic balloon dilation in caustic-induced gastric injury.

PubMed

Kochhar, Rakesh; Poornachandra, Kuchhangi Sureshchandra; Dutta, Usha; Agrawal, Amit; Singh, Kartar

2010-04-01

There are no reports on endoscopic balloon dilation (EBD) for caustic-induced gastric outlet obstruction (GOO) in the acute or subacute phase. To study the efficacy of early EBD in patients with caustic-induced gastric injury. Tertiary care center in India. Retrospective analysis of data. Out of 41 patients with caustic-induced GOO who reported to us in the subacute phase between January 2001 and December 2008, 31 were treated by EBD. All 31 had ingested an acid 14.39 +/- 4.65 days earlier. EBD was achieved by using wire-guided balloons under endoscopic guidance. The balloon was negotiated across the narrowed segment and inflated for 60 seconds using a pressure gun. Balloons of incremental diameter, up to a maximum of 3 sizes, were used in each sitting. Procedural success was defined as reaching the end point of dilation (15 mm) and absence of symptoms. All 31 patients (18 male, mean age 32.06 +/- 11.04 years) could be successfully dilated. All but 1 underwent successful dilations to achieve the end point of 15 mm, requiring a median of 9 (range 3-18) dilations over a period of 7 (range 1.5-16) weeks. Complications included self-limiting pain (n = 10), bleeding at the time of the procedure (n = 9), and perforation in 1 patient (3.2%) who required surgery. Thirty patients were followed up for a median of 21 (range 3-72) months with no recurrence. Early EBD by an expert endoscopist is a safe and effective treatment modality in the management of caustic-induced GOO. Copyright 2010 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

A quantitative model of application slow-down in multi-resource shared systems

DOE PAGES

Lim, Seung-Hwan; Kim, Youngjae

2016-12-26

Scheduling multiple jobs onto a platform enhances system utilization by sharing resources. The benefits from higher resource utilization include reduced cost to construct, operate, and maintain a system, which often include energy consumption. Maximizing these benefits comes at a price-resource contention among jobs increases job completion time. In this study, we analyze slow-downs of jobs due to contention for multiple resources in a system; referred to as dilation factor. We observe that multiple-resource contention creates non-linear dilation factors of jobs. From this observation, we establish a general quantitative model for dilation factors of jobs in multi-resource systems. A job ismore » characterized by a vector-valued loading statistics and dilation factors of a job set are given by a quadratic function of their loading vectors. We demonstrate how to systematically characterize a job, maintain the data structure to calculate the dilation factor (loading matrix), and calculate the dilation factor of each job. We validate the accuracy of the model with multiple processes running on a native Linux server, virtualized servers, and with multiple MapReduce workloads co-scheduled in a cluster. Evaluation with measured data shows that the D-factor model has an error margin of less than 16%. We extended the D-factor model to capture the slow-down of applications when multiple identical resources exist such as multi-core environments and multi-disks environments. Finally, validation results of the extended D-factor model with HPC checkpoint applications on the parallel file systems show that D-factor accurately captures the slow down of concurrent applications in such environments.« less

Recent Clinical Drug Trials Evidence in Marfan Syndrome and Clinical Implications.

PubMed

Singh, Michael N; Lacro, Ronald V

2016-01-01

Marfan syndrome is a genetic disorder of connective tissue with principal manifestations in the cardiovascular, ocular, and skeletal systems. Cardiovascular disease, mainly progressive aortic root dilation and aortic dissection, is the leading cause of morbidity and mortality. The primary aims of this report were to examine the evidence related to medical therapy for Marfan syndrome, including recently completed randomized clinical trials on the efficacy of β-blockers and angiotensin II receptor blockers for the prophylactic treatment of aortic enlargement in Marfan syndrome, and to provide recommendations for medical therapy on the basis of available evidence. Medical therapy for Marfan syndrome should be individualized according to patient tolerance and risk factors such as age, aortic size, and family history of aortic dissection. The Pediatric Heart Network trial showed that atenolol and losartan each reduced the rate of aortic dilation. All patients with known or suspected Marfan syndrome and aortic root dilation should receive medical therapy with adequate doses of either β-blocker or angiotensin receptor blocker. The Pediatric Heart Network trial also showed that atenolol and losartan are more effective at reduction of aortic root z score in younger subjects, which suggests that medical therapy should be prescribed even in the youngest children with aortic dilation. For patients with Marfan syndrome without aortic dilation, the available evidence is less clear. If aortic dilation is severe and/or progressive, therapy with a combination of β-blocker and angiotensin receptor blocker should be considered, although trial results are mixed with respect to the efficacy of combination therapy vs monotherapy. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Exaggerated cardiovascular effects of cocaine in conscious dogs with pacing-induced dilated cardiomyopathy.

PubMed

Mathier, Michael A; Shen, You-Tang; Shannon, Richard P

2002-12-01

The aim of this study was to explore the characteristics and mechanisms of the cardiovascular effects of cocaine in dilated cardiomyopathy. We studied the cardiovascular responses to acute intravenous cocaine (1 mg/kg) in 8 conscious, chronically instrumented dogs before and after the development of dilated cardiomyopathy induced by rapid ventricular pacing. To help elucidate the role of altered baroreflex function in mediating the cardiovascular effects of cocaine, we also studied responses in 3 conscious, chronically instrumented dogs that had undergone surgical sinoaortic baroreceptor denervation. Cocaine produced greater increases in heart rate (+57 +/- 8% from 112 +/- 5 beats/min versus +28 +/- 3% from 100 +/- 4 beats/min; P <.01), first derivative of left ventricular pressure (+30 +/- 5% from 1,714 +/- 147 mm Hg/sec versus +15 +/- 3% from 3,032 +/- 199 mm Hg/sec; P <.01), coronary vascular resistance (+28 +/- 5% from 2.3 +/- 0.3 mm Hg/mL/min versus +11 +/- 5% from 2.2 +/- 0.3 mm Hg/mL/min; P <.05) and plasma norepinephrine concentration (+130 +/- 31% from 462 +/- 102 pg/mL versus +86 +/- 32% from 286 +/- 77 pg/mL; P <.05) in dogs with dilated cardiomyopathy as compared to controls. In addition, responses were much more rapid in onset following the development of dilated cardiomyopathy. Chronotropic and inotropic responses to cocaine were similarly rapid and exaggerated in dogs after baroreceptor denervation. Cocaine produces rapid and exaggerated chronotropic, inotropic, and coronary vasoconstrictor responses in conscious dogs with pacing-induced dilated cardiomyopathy. Alterations in arterial baroreflex function may play a role in these observations, which in turn may underlie the clinically observed association between cocaine and heart failure.

Expectant management compared with physical examination-indicated cerclage (EM-PEC) in selected women with a dilated cervix at 14(0/7)-25(6/7) weeks: results from the EM-PEC international cohort study.

PubMed

Pereira, Leonardo; Cotter, Amanda; Gómez, Ricardo; Berghella, Vincenzo; Prasertcharoensuk, Witoon; Rasanen, Juha; Chaithongwongwatthana, Surasith; Mittal, Suneeta; Daly, Sean; Airoldi, Jim; Tolosa, Jorge E

2007-11-01

The objective of the study was to compare pregnancy outcomes in selected women with a dilated cervix who underwent expectant management or physical examination-indicated cerclage. This was a historical cohort study conducted by the Global Network for Perinatal and Reproductive Health. Women between 14(0/7) and 25(6/7) weeks' gestation with a dilated cervix were identified at 10 centers by ultrasound or digital examination. Primary outcome was time from presentation until delivery (weeks). Secondary outcomes were neonatal survival, birthweight greater than 1500 g and preterm birth less than 28 weeks. Multivariate regression was used to assess the likelihood of neonatal outcomes and control for confounders. Of 225 women, 152 received a physical examination-indicated cerclage, and 73 were managed expectantly without cerclage. Cervical dilation, gestational age at presentation, and antenatal steroid use differed between groups. In the adjusted analyses, cerclage was associated with longer interval from presentation until delivery, improved neonatal survival, birthweight greater than 1500 g and preterm birth less than 28 weeks, compared with expectant management. Similar results were obtained in the analyses limited to women dilated between 2 and 4 cm (n = 122). In this study, the largest cohort reported to date, physical examination-indicated cerclage appears to prolong gestation and improve neonatal survival, compared with expectant management in selected women with cervical dilation between 14(0/7) and 25(6/7) weeks. A randomized, controlled trial should be conducted to determine whether these potential benefits outweigh the risks of cerclage placement in this population.

Balloon dilation of the eustachian tube for dilatory dysfunction: A randomized controlled trial.

PubMed

Poe, Dennis; Anand, Vijay; Dean, Marc; Roberts, William H; Stolovitzky, Jose Pablo; Hoffmann, Karen; Nachlas, Nathan E; Light, Joshua P; Widick, Mark H; Sugrue, John P; Elliott, C Layton; Rosenberg, Seth I; Guillory, Paul; Brown, Neil; Syms, Charles A; Hilton, Christopher W; McElveen, John T; Singh, Ameet; Weiss, Raymond L; Arriaga, Moises A; Leopold, John P

2018-05-01

To assess balloon dilation of the Eustachian tube with Eustachian tube balloon catheter in conjunction with medical management as treatment for Eustachian tube dilatory dysfunction. In this prospective, multicenter, randomized, controlled trial, we assigned, in a 2:1 ratio, patients age 22 years and older with Eustachian tube dilatory dysfunction refractory to medical therapy to undergo balloon dilation of the Eustachian tube with balloon catheter in conjunction with medical management or medical management alone. The primary endpoint was normalization of tympanogram at 6 weeks. Additional endpoints were normalization of Eustachian Tube Dysfunction Questionaire-7 symptom scores, positive Valsalva maneuver, mucosal inflammation, and safety. Primary efficacy results demonstrated superiority of balloon dilation of the Eustachian tube with balloon catheter + medical management compared to medical management alone. Tympanogram normalization at 6-week follow-up was observed in 51.8% (72/139) of investigational patients versus 13.9% (10/72) of controls (P < .0001). Tympanogram normalization in the treatment group was 62.2% after 24 weeks. Normalization of Eustachian Tube Dysfunction Questionaire-7 Symptom scores at 6-week follow-up was observed in 56.2% (77/137) of investigational patients versus 8.5% (6/71) controls (P < .001). The investigational group also demonstrated substantial improvement in both mucosal inflammation and Valsalva maneuver at 6-week follow-up compared to controls. No device- or procedure-related serious adverse events were reported for those who underwent balloon dilation of the Eustachian tube. This study demonstrated superiority of balloon dilation of the Eustachian tube with balloon catheter + medical management compared to medical management alone to treat Eustachian tube dilatory dysfunction in adults. 1b. Laryngoscope, 128:1200-1206, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

SMAD4 gene mutation increases the risk of aortic dilation in patients with hereditary haemorrhagic telangiectasia.

PubMed

Vorselaars, V M M; Diederik, A; Prabhudesai, V; Velthuis, S; Vos, J-A; Snijder, R J; Westermann, C J J; Mulder, B J; Ploos van Amstel, J K; Mager, J J; Faughnan, M E; Post, M C

2017-10-15

Mutations in the genes ENG, ACVRL1 and SMAD4 that are part of the transforming growth factor-beta signalling pathway cause hereditary haemorrhagic telangiectasia (HHT). Mutations in non-HHT genes within this same pathway have been found to associate with aortic dilation. Therefore, we investigated the presence of aortic dilation in a large cohort of HHT patients as compared to non-HHT controls. Chest computed tomography of consecutive HHT patients (ENG, ACVRL1 and SMAD4 mutation carriers) and non-HHT controls were reviewed. Aortic root dilation was defined as a z-score>1.96. Ascending and descending aorta dimensions were corrected for age, gender and body surface area. In total 178 subjects (57.3% female, mean age 43.9±14.9years) were included (32 SMAD4, 47 ENG, 50 ACVRL1 mutation carriers and 49 non-HHT controls). Aortopathy was present in a total of 42 subjects (24% of total). Aortic root dilatation was found in 31% of SMAD4, 2% of ENG, 6% of ACVRL1 mutation carriers, and 4% in non-HHT controls (p<0.001). The aortic root diameter was 36.3±5.2mm in SMAD4 versus 32.7±3.9mm in the non-SMAD4 group (p=0.001). SMAD4 was an independent predictor for increased aortic root (β-coefficient 3.5, p<0.001) and ascending aorta diameter (β-coefficient 1.6, p=0.04). SMAD4 gene mutation in HHT patients is independently associated with a higher risk of aortic root and ascending aortic dilation as compared to other HHT patients and non-HHT controls. Copyright © 2017 Elsevier B.V. All rights reserved.

A quantitative model of application slow-down in multi-resource shared systems

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

Lim, Seung-Hwan; Kim, Youngjae

Scheduling multiple jobs onto a platform enhances system utilization by sharing resources. The benefits from higher resource utilization include reduced cost to construct, operate, and maintain a system, which often include energy consumption. Maximizing these benefits comes at a price-resource contention among jobs increases job completion time. In this study, we analyze slow-downs of jobs due to contention for multiple resources in a system; referred to as dilation factor. We observe that multiple-resource contention creates non-linear dilation factors of jobs. From this observation, we establish a general quantitative model for dilation factors of jobs in multi-resource systems. A job ismore » characterized by a vector-valued loading statistics and dilation factors of a job set are given by a quadratic function of their loading vectors. We demonstrate how to systematically characterize a job, maintain the data structure to calculate the dilation factor (loading matrix), and calculate the dilation factor of each job. We validate the accuracy of the model with multiple processes running on a native Linux server, virtualized servers, and with multiple MapReduce workloads co-scheduled in a cluster. Evaluation with measured data shows that the D-factor model has an error margin of less than 16%. We extended the D-factor model to capture the slow-down of applications when multiple identical resources exist such as multi-core environments and multi-disks environments. Finally, validation results of the extended D-factor model with HPC checkpoint applications on the parallel file systems show that D-factor accurately captures the slow down of concurrent applications in such environments.« less

Resveratrol Inhibits Aortic Root Dilatation in the Fbn1C1039G/+ Marfan Mouse Model.

PubMed

Hibender, Stijntje; Franken, Romy; van Roomen, Cindy; Ter Braake, Anique; van der Made, Ingeborg; Schermer, Edith E; Gunst, Quinn; van den Hoff, Maurice J; Lutgens, Esther; Pinto, Yigal M; Groenink, Maarten; Zwinderman, Aeilko H; Mulder, Barbara J M; de Vries, Carlie J M; de Waard, Vivian

2016-08-01

Marfan syndrome (MFS) is a connective tissue disorder caused by mutations in the fibrillin-1 gene. Patients with MFS are at risk of aortic aneurysm formation and dissection. Usually, blood pressure-lowering drugs are used to reduce aortic events; however, this is not sufficient for most patients. In the aorta of smooth muscle cell-specific sirtuin-1-deficient mice, spontaneous aneurysm formation and senescence are observed. Resveratrol is known to enhance sirtuin-1 activity and to reduce senescence, which prompted us to investigate the effectiveness of resveratrol in inhibition of aortic dilatation in the Fbn1(C1039G/+) MFS mouse model. Aortic senescence strongly correlates with aortic root dilatation rate in MFS mice. However, although resveratrol inhibits aortic dilatation, it only shows a trend toward reduced aortic senescence. Resveratrol enhances nuclear localization of sirtuin-1 in the vessel wall and, in contrast to losartan, does not affect leukocyte infiltration nor activation of SMAD2 and extracellular signal-regulated kinases 1/2 (ERK1/2). Interestingly, specific sirtuin-1 activation (SRT1720) or inhibition (sirtinol) in MFS mice does not affect aortic root dilatation rate, although senescence is changed. Resveratrol reduces aortic elastin breaks and decreases micro-RNA-29b expression coinciding with enhanced antiapoptotic Bcl-2 expression and decreased number of terminal apoptotic cells. In cultured smooth muscle cells, the resveratrol effect on micro-RNA-29b downregulation is endothelial cell and nuclear factor κB-dependent. Resveratrol inhibits aortic root dilatation in MFS mice by promoting elastin integrity and smooth muscle cell survival, involving downregulation of the aneurysm-related micro-RNA-29b in the aorta. On the basis of these data, resveratrol holds promise as a novel intervention strategy for patients with MFS. © 2016 The Authors.

Resveratrol Inhibits Aortic Root Dilatation in the Fbn1C1039G/+ Marfan Mouse Model

PubMed Central

Hibender, Stijntje; Franken, Romy; van Roomen, Cindy; ter Braake, Anique; van der Made, Ingeborg; Schermer, Edith E.; Gunst, Quinn; van den Hoff, Maurice J.; Lutgens, Esther; Pinto, Yigal M.; Groenink, Maarten; Zwinderman, Aeilko H.; Mulder, Barbara J.M.; de Vries, Carlie J.M.

2016-01-01

Objective— Marfan syndrome (MFS) is a connective tissue disorder caused by mutations in the fibrillin-1 gene. Patients with MFS are at risk of aortic aneurysm formation and dissection. Usually, blood pressure–lowering drugs are used to reduce aortic events; however, this is not sufficient for most patients. In the aorta of smooth muscle cell–specific sirtuin-1–deficient mice, spontaneous aneurysm formation and senescence are observed. Resveratrol is known to enhance sirtuin-1 activity and to reduce senescence, which prompted us to investigate the effectiveness of resveratrol in inhibition of aortic dilatation in the Fbn1C1039G/+ MFS mouse model. Approach and Results— Aortic senescence strongly correlates with aortic root dilatation rate in MFS mice. However, although resveratrol inhibits aortic dilatation, it only shows a trend toward reduced aortic senescence. Resveratrol enhances nuclear localization of sirtuin-1 in the vessel wall and, in contrast to losartan, does not affect leukocyte infiltration nor activation of SMAD2 and extracellular signal–regulated kinases 1/2 (ERK1/2). Interestingly, specific sirtuin-1 activation (SRT1720) or inhibition (sirtinol) in MFS mice does not affect aortic root dilatation rate, although senescence is changed. Resveratrol reduces aortic elastin breaks and decreases micro-RNA-29b expression coinciding with enhanced antiapoptotic Bcl-2 expression and decreased number of terminal apoptotic cells. In cultured smooth muscle cells, the resveratrol effect on micro-RNA-29b downregulation is endothelial cell and nuclear factor κB-dependent. Conclusions— Resveratrol inhibits aortic root dilatation in MFS mice by promoting elastin integrity and smooth muscle cell survival, involving downregulation of the aneurysm-related micro-RNA-29b in the aorta. On the basis of these data, resveratrol holds promise as a novel intervention strategy for patients with MFS. PMID:27283746

Acute increases in intraluminal pressure improve vasodilator responses in aged soleus muscle feed arteries.

PubMed

Seawright, John W; Luttrell, Meredith J; Woodman, Christopher R

2014-10-01

We tested the hypothesis that exposure to an acute increase in intraluminal pressure, to mimic pressure associated with a bout of exercise, improves nitric oxide (NO)-mediated endothelium-dependent dilation in aged soleus muscle feed arteries (SFA) and that improved endothelial function would persist after a 2 h recovery period. SFA from young (4-month) and old (24-month) Fischer 344 rats were cannulated and pressurized at 90 (P90) or 130 (P130) cmH2O for 60 min. At the end of the treatment period, pressure in the P130 SFA was lowered to 90 cmH2O for examination of endothelium-dependent [flow or acetylcholine (ACh)] and endothelium-independent [sodium nitroprusside (SNP)] vasodilation. To determine the role of NO, vasodilator responses were assessed in the presence of N (ω)-nitro-L-arginine (L-NNA). To determine whether the effects of pressure persisted following a recovery period at normal pressure, SFA were pressurized to 130 cmH2O for 60 min and subsequently lowered to 90 cmH2O for 2 h before assessing function. ACh- and flow-induced dilations were impaired in old SFA. Treatment with increased pressure for 60 min improved ACh- and flow-induced dilations in old SFA. SNP-induced dilation was improved in old and young SFA. The beneficial effect of pressure treatment on ACh- and flow-induced dilation in old SFA was blocked by L-NNA and was not present following a 2 h recovery period. These results indicate that an acute increase in intraluminal pressure improves NO-mediated endothelium-dependent dilation in aged SFA; however, the beneficial effect does not persist after 2 h.

Insulin resistance adds to endothelial dysfunction in hypertensive patients and in normotensive offspring of subjects with essential hypertension.

PubMed

Zizek, B; Poredos, P

2001-02-01

To evaluate whether endothelium-dependent (nitric oxide-mediated) dilation of the brachial artery (BA) is impaired in patients being treated for essential hypertension (EH), and whether this abnormality can be detected in normotensive offspring of subjects with EH (familial trait, FT); and to investigate the interrelationship between flow-mediated vasodilation (FMD) and hyperinsulinaemia/insulin resistance. Cross-sectional study. Angiology department at a teaching hospital. The study encompassed 172 subjects, of whom 46 were treated hypertonics aged 40-55 (49) years, and 44 age-matched, normotensive volunteers as controls. We also investigated 41 normotonics with FT aged 20-30 (25) years and 41 age-and sex-matched controls without FT. Using high-resolution ultrasound, BA diameters at rest, during reactive hyperaemia (endothelium-dependent dilation) and after sublingual glyceryl trinitrate (GTN) application (endothelium-independent dilation) were measured. In hypertonics FMD was significantly lower than in controls [2.4 (2.9) vs. 7.4 (2.5)%; P < 0.00005], as was GTN-induced dilation [12.1 (4.3) vs. 16.1 (4.6)%; P=0.0007]. In subjects with FT, FMD was also decreased compared with the control group [5.8 (4.1) vs. 10.0 (3.0)%; P < 0.00005]. The response to GTN was comparable in both groups of young subjects. FMD was negatively related to insulin concentration in all subjects studied (P < 0.00005). In treated patients with EH, flow-mediated dilation of the BA as well as endothelium-independent dilation are decreased. In individuals with FT the endothelial function of the peripheral arteries is also altered in the absence of elevated blood pressure. Endothelial dysfunction is related to hyperinsulinaemia/insulin resistance, which could be one of the pathogenetic determinants of EH and its complications.

Analysis of chemosensory function in patients with chronic Eustachian tube dysfunction prior to and after balloon dilatation.

PubMed

Ute, Walliczek-Dworschak; Lisa, Schmierer; Brandon, Greene; Robert, Pellegrino; Philipp, Dworschak; Stuck, Boris Alexander; Christian, Güldner

2018-10-01

Eustachian tube dysfunction (ETD) affects approximately 1% of adults in the general population. Non treated Eustachian tube dysfunction can result in chronic middle ear diseases, which have been shown to significantly affect taste sensitivity. A promising treatment is balloon dilatation of the Eustachian tube. The primary aim of the present study was to investigate whether individuals with ETD had impairment in chemosensory functions, and the changes of the chemosensory function after balloon dilatation of the Eustachian tube. 26 patients (17 female, 9 male) (=56 ears) suffering from ETD with a mean age of 39±15years were included in the present study. 20 patients (76%) returned to be evaluated at the follow up (=40 ears) 51±22days after balloon dilatation. For pre- and post operation, gustatory function was measured with a lateralized gustatory test with the taste strips and olfactory function was tested by means of the Sniffin' Sticks test battery (threshold, discrimination and identification (ID)). Patients' baseline taste function (summed taste score 9.8±3.5 (mean±SD)) was significantly impaired compared to normative data (summed taste score 12.4±2.3; p=0.002). After balloon dilatation of the Eustachian tube, the taste function remained stable (summed taste score 9.4±4.3; p=0.814). Olfactory function (odor ID, summed score (TDI)) improved postoperatively (TDI 32.4±3.6) compared to pre-operative scores (TDI 33.6±4.0; p=0.012), but not to a clinically relevant extent. This study suggests, that patients suffering from ETD exhibit reduced taste scores. Balloon dilatation of the Eustachian tube does not seem to influence gustatory function, but olfactory function showed improvement. Copyright © 2018 Elsevier B.V. All rights reserved.

[A clinical observation of percutaneous balloon dilation and maintenance percutaneous transhepatic cholangial catheter drainage for treatment of 21 patients with benign biliary strictures and difficult endoscopy].

PubMed

Pan, Jie; Shi, Hai-feng; Li, Xiao-guang; Zhang, Xiao-bo; Liu, Wei; Jin, Zheng-yu; Hong, Tao; Yang, Ai-ming; Yang, Ning

2012-06-01

To investigate the value of percutaneous balloon dilation and percutaneous transhepatic cholangial drainage (PTCD) catheter maintenance in the treatment of benign biliary strictures. The clinical data of 21 patients with benign biliary strictures at Peking Union Medical College Hospital from June 2005 to June 2011 were retrospectively studied, in which 12 patients in severe stricture (stenosis > 70%) were treated with percutaneous balloon dilation and PTCD catheter placed across the stricture, while another 9 patients in median stricture (stenosis < 70%) were only treated with PTCD catheter maintenance. Of the 12 patients underwent balloon dilation and 6 - 12 months (median: 9 months) of PTCD catheter placement, 11 patients had the catheter successfully removed. In the follow-up of 6 - 24 months (median: 10 months), patency of bile duct was preserved in 9 of 11 patients, and recurrent stenosis was seen in 2 patients. A severe complication with biliary artery branch rupture and massive hemobilia was seen in 1 patient during balloon dilation. Of the 9 patients only treated with 1 - 12 months (median: 6 months) of PTCD catheter placement, 7 patients had the catheter successfully removed. In the follow-up of 5 - 18 months (median: 8 months), patency of bile duct was preserved in 5 of 7 patients, and recurrent stenosis was seen in 2 patients. No severe complication occurred. When endoscopy therapy is failed or the patient can't undergo endoscopy therapy, the percutaneous balloon dilation and PTCD catheter maintenance method is an effective alternative therapeutic approach in the treatment of benign biliary strictures. The moderate benign biliary stricture may be effectively treated only by the PTCD catheter maintenance method.

Endoscopic management of esophageal stenosis in children: New and traditional treatments.

PubMed

Dall'Oglio, Luigi; Caldaro, Tamara; Foschia, Francesca; Faraci, Simona; Federici di Abriola, Giovanni; Rea, Francesca; Romeo, Erminia; Torroni, Filippo; Angelino, Giulia; De Angelis, Paola

2016-02-25

Post-esophageal atresia anastomotic strictures and post-corrosive esophagitis are the most frequent types of cicatricial esophageal stricture. Congenital esophageal stenosis has been reported to be a rare but typical disease in children; other pediatric conditions are peptic, eosinophilic esophagitis and dystrophic recessive epidermolysis bullosa strictures. The conservative treatment of esophageal stenosis and strictures (ES) rather than surgery is a well-known strategy for children. Before planning esophageal dilation, the esophageal morphology should be assessed in detail for its length, aspect, number and level, and different conservative strategies should be chosen accordingly. Endoscopic dilators and techniques that involve different adjuvant treatment strategies have been reported and depend on the stricture's etiology, the availability of different tools and the operator's experience and preferences. Balloon and semirigid dilators are the most frequently used tools. No high-quality studies have reported on the differences in the efficacies and rates of complications associated with these two types of dilators. There is no consensus in the literature regarding the frequency of dilations or the diameter that should be achieved. The use of adjuvant treatments has been reported in cases of recalcitrant stenosis or strictures with evidence of dysphagic symptoms. Corticosteroids (either systemically or locally injected), the local application of mitomycin C, diathermy and laser ES sectioning have been reported. Some authors have suggested that stenting can reduce both the number of dilations and the treatment length. In many cases, this strategy is effective when either metallic or plastic stents are utilized. Treatment complications, such esophageal perforations, can be conservatively managed, considering surgery only in cases with severe pleural cavity involvement. In cases of stricture relapse, even if such relapses occur following the execution of well-conducted conservative strategies, surgical stricture resection and anastomosis or esophageal substitution are the only remaining options.

Contribution of Optical Zone Decentration and Pupil Dilation on the Change of Optical Quality After Myopic Photorefractive Keratectomy in a Cat Model

PubMed Central

Bühren, Jens; Yoon, Geunyoung; MacRae, Scott; Huxlin, Krystel

2010-01-01

PURPOSE To simulate the simultaneous contribution of optical zone decentration and pupil dilation on retinal image quality using wavefront error data from a myopic photorefractive keratectomy (PRK) cat model. METHODS Wavefront error differences were obtained from five cat eyes 19±7 weeks (range: 12 to 24 weeks) after spherical myopic PRK for −6.00 diopters (D) (three eyes) and −10.00 D (two eyes). A computer model was used to simulate decentration of a 6-mm sub-aperture relative to the measured wavefront error difference. Changes in image quality (visual Strehl ratio based on the optical transfer function [VSOTF]) were computed for simulated decentrations from 0 to 1500 μm over pupil diameters of 3.5 to 6.0 mm in 0.5-mm steps. For each eye, a bivariate regression model was applied to calculate the simultaneous contribution of pupil dilation and decentration on the pre- to postoperative change of the log VSOTF. RESULTS Pupil diameter and decentration explained up to 95% of the variance of VSOTF change (adjusted R2=0.95). Pupil diameter had a higher impact on VSOTF (median β=−0.88, P<.001) than decentration (median β= −0.45, P<.001). If decentration-induced lower order aberrations were corrected, the impact of decentration further decreased (β= −0.26) compared to the influence of pupil dilation (β= −0.95). CONCLUSIONS Both pupil dilation and decentration of the optical zone affected the change of retinal image quality (VSOTF) after myopic PRK with decentration exerting a lower impact on VSOTF change. Thus, under physiological conditions pupil dilation is likely to have more effect on VSOTF change after PRK than optical zone decentration. PMID:20229950

Contribution of optical zone decentration and pupil dilation on the change of optical quality after myopic photorefractive keratectomy in a cat model.

PubMed

Bühren, Jens; Yoon, Geunyoung; MacRae, Scott; Huxlin, Krystel

2010-03-01

To simulate the simultaneous contribution of optical zone decentration and pupil dilation on retinal image quality using wavefront error data from a myopic photorefractive keratectomy (PRK) cat model. Wavefront error differences were obtained from five cat eyes 19+/-7 weeks (range: 12 to 24 weeks) after spherical myopic PRK for -6.00 diopters (D) (three eyes) and -10.00 D (two eyes). A computer model was used to simulate decentration of a 6-mm sub-aperture relative to the measured wavefront error difference. Changes in image quality (visual Strehl ratio based on the optical transfer function [VSOTF]) were computed for simulated decentrations from 0 to 1500 mum over pupil diameters of 3.5 to 6.0 mm in 0.5-mm steps. For each eye, a bivariate regression model was applied to calculate the simultaneous contribution of pupil dilation and decentration on the pre- to postoperative change of the log VSOTF. Pupil diameter and decentration explained up to 95% of the variance of VSOTF change (adjusted R(2)=0.95). Pupil diameter had a higher impact on VSOTF (median beta=-0.88, P<.001) than decentration (median beta=-0.45, P<.001). If decentration-induced lower order aberrations were corrected, the impact of decentration further decreased (beta=-0.26) compared to the influence of pupil dilation (beta=-0.95). Both pupil dilation and decentration of the optical zone affected the change of retinal image quality (VSOTF) after myopic PRK with decentration exerting a lower impact on VSOTF change. Thus, under physiological conditions pupil dilation is likely to have more effect on VSOTF change after PRK than optical zone decentration. Copyright 2010, SLACK Incorporated.

Identification of new biophysical markers for pathological ventricular remodelling in tachycardia-induced dilated cardiomyopathy.

PubMed

Benitez-Amaro, Aleyda; Samouillan, Valerie; Jorge, Esther; Dandurand, Jany; Nasarre, Laura; de Gonzalo-Calvo, David; Bornachea, Olga; Amoros-Figueras, Gerard; Lacabanne, Colette; Vilades, David; Leta, Ruben; Carreras, Francesc; Gallardo, Alberto; Lerma, Enrique; Cinca, Juan; Guerra, Jose M; Llorente-Cortés, Vicenta

2018-06-19

Our aim was to identify biophysical biomarkers of ventricular remodelling in tachycardia-induced dilated cardiomyopathy (DCM). Our study includes healthy controls (N = 7) and DCM pigs (N = 10). Molecular analysis showed global myocardial metabolic abnormalities, some of them related to myocardial hibernation in failing hearts, supporting the translationality of our model to study cardiac remodelling in dilated cardiomyopathy. Histological analysis showed unorganized and agglomerated collagen accumulation in the dilated ventricles and a higher percentage of fibrosis in the right (RV) than in the left (LV) ventricle (P = .016). The Fourier Transform Infrared Spectroscopy (FTIR) 1st and 2nd indicators, which are markers of the myofiber/collagen ratio, were reduced in dilated hearts, with the 1st indicator reduced by 45% and 53% in the RV and LV, respectively, and the 2nd indicator reduced by 25% in the RV. The 3rd FTIR indicator, a marker of the carbohydrate/lipid ratio, was up-regulated in the right and left dilated ventricles but to a greater extent in the RV (2.60-fold vs 1.61-fold, P = .049). Differential scanning calorimetry (DSC) showed a depression of the freezable water melting point in DCM ventricles - indicating structural changes in the tissue architecture - and lower protein stability. Our results suggest that the 1st, 2nd and 3rd FTIR indicators are useful markers of cardiac remodelling. Moreover, the 2nd and 3rd FITR indicators, which are altered to a greater extent in the right ventricle, are associated with greater fibrosis. © 2018 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Preoperative ripening of the cervix before operative hysteroscopy.

PubMed

Al-Fozan, Haya; Firwana, Belal; Al Kadri, Hanan; Hassan, Samar; Tulandi, Togas

2015-04-23

Hysteroscopy is an operation in which the gynaecologist examines the uterine cavity using a small telescopic instrument (hysteroscope) inserted via the vagina and the cervix. Almost 50% of hysteroscopic complications are related to difficulty with cervical entry. Potential complications include cervical tears, creation of a false passage, perforation, bleeding, or simply difficulty in entering the internal os (between the cervix and the uterus) with the hysteroscope. These complications may possibly be reduced with adequate preparation of the cervix (cervical ripening) prior to hysteroscopy. Cervical ripening agents include oral or vaginal prostaglandin, which can be synthetic (e.g misoprostol) or natural (e.g. dinoprostone) and vaginal osmotic dilators, which can be naturally occurring (e.g. laminaria) or synthetic. To determine whether preoperative cervical preparation facilitates cervical dilatation and reduces the complications of operative hysteroscopy in women undergoing the procedure for any condition. In August 2014 we searched sources including the Menstrual Disorders and Subfertility Group (MDSG) Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycINFO, CINAHL, ClinicalTrials.gov and reference lists of relevant articles. We searched for published and unpublished studies in any language. Two review authors independently selected randomised controlled trials (RCTs) of cervical ripening agents used before operative hysteroscopy in pre- and postmenopausal women. Cervical ripening agents could be compared to each other, placebo or no treatment. Data extraction and quality assessment were conducted independently by two review authors. The primary review outcomes were effectiveness of cervical dilatation (defined as the proportion of women requiring mechanical cervical dilatation) and intraoperative complications. Secondary outcomes were mean time required to dilate the cervix, preoperative pain, cervical width, abandonment of the procedure, side effects of dilating agents and duration of surgery. We calculated odds ratios (ORs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, with 95% confidence intervals ( CIs). Data were statistically pooled where appropriate. Heterogeneity was assessed using the I(2) statistic. The overall quality of the evidence was assessed using GRADE methods. Nineteen RCTs with a total of 1870 participants were included. They compared misoprostol with no treatment or placebo, dinoprostone or osmotic dilators.Misoprostol was more effective for cervical dilatation than placebo or no intervention, with fewer women requiring mechanical dilatation (OR 0.08, 95% CI 0.04 to 0.16, five RCTs, 441 participants, I(2)=0%, moderate quality evidence). This suggests that in a population in which 80% of women undergoing hysteroscopy require mechanical dilatation without use of preoperative ripening agents, use of misoprostol will reduce the need for mechanical dilatation to between 14% and 39%. Misoprostol was associated with fewer intraoperative complications (OR 0.37, 95% CI 0.18 to 0.77, 12 RCTs, 901 participants, I(2)=0%, moderate quality evidence). This suggests that in a population in which 3% of women undergoing hysteroscopy experience intraoperative complications without use of preoperative ripening agents, use of misoprostol will reduce the risk of complications to 2% or less.When specific complications were considered, the misoprostol group had a lower rate of cervical laceration or tearing (OR 0.25, 95% CI 0.11 to 0.57, nine RCTS, 669 women, I(2)=0%, moderate quality evidence) or false track formation (OR 0.34, 95% CI 0.12 to 0.97, seven RCTs, 560 participants, I(2)=0%, moderate quality evidence). There was no evidence of a difference between the groups in rates of uterine perforation (0.42, 95% CI 0.13 to 1.38, seven RCTs, 455 participants, I(2)=0%, low quality evidence) or uterine bleeding (OR 0.51, 95% CI 0.10 to 2.49, four RCTs, 340 participants, I(2)=0%, low quality evidence). Some treatment side effects (mild abdominal pain, vaginal bleeding, and increased body temperature) were more common in the misoprostol group.Compared with dinoprostone, misoprostol was associated with more effective cervical dilatation, with fewer women requiring mechanical dilatation (OR 0.58; 95% CI 0.34 to 0.98; one RCT, 310 participants, low quality evidence) and with fewer intraoperative complications (OR 0.32; 95% CI 0.12 to 0.83, one RCT, 310 participants, low quality evidence). However treatment side effects were more common in the misoprostol arm.Compared to osmotic dilatation (laminaria), misoprostol was associated with less effective cervical dilatation, with more women in the misoprostol group requiring mechanical dilatation (OR 5.96, 95% CI 2.61 to 13.59, one RCT, 110 participants, low quality evidence). There was no evidence of a difference between misoprostol and osmotic dilators in intraoperative complication rates (OR 5.14, 95% CI 0.24 to 109.01, three RCTs, 354 participants, low quality evidence), with only two events reported altogether.The overall quality of the evidence ranged from low to moderate. The main limitations in the evidence were imprecision and poor reporting of study methods. There is moderate quality evidence that use of misoprostol for preoperative ripening of the cervix before operative hysteroscopy is more effective than placebo or no treatment and is associated with fewer intraoperative complications such as lacerations and false tracks. However misoprostol is associated with more side effects, including preoperative pain and vaginal bleeding. There is low quality evidence to suggest that misoprostol has fewer intraoperative complications and is more effective than dinoprostone.There is also low quality evidence to suggest that laminaria may be more effective than misoprostol, with uncertain effects for complication rates. However the possible benefits of laminaria need to be weighed against the inconvenience of its insertion and retention for one to two days.

Dilated cardiomyopathy with short QT interval: is it a new clinical entity?

PubMed

Bohora, Shomu; Namboodiri, Narayanan; Tharakan, Jaganmohan; Vk, Ajit Kumara; Nayyar, Sachin

2009-05-01

Short QT syndrome is a rare autosomal dominant channelopathy of structurally normal hearts characterized by atrial fibrillation, ventricular arrhythmias, and sudden cardiac death. We report a case having short QT, dilated ventricles, and severe ventricular dysfunction, an unreported association so far.

Arborescent vascular dilatation mimicking Lichtenberg figures from lightning.

PubMed

Tempark, Therdpong; Iwasaki, Julie; Shwayder, Tor

2014-01-01

The clinical presentation of arborizing vascular dilatation can resemble Lichtenberg figures from lightning. Both have a feather-like or ferning pattern. We report an interesting case of pressure-induced vasodilatation (PIV) caused by temporary vascular occlusion from jeans buttons. © 2014 Wiley Periodicals, Inc.

21 CFR 874.4420 - Ear, nose, and throat manual surgical instrument.

Code of Federal Regulations, 2010 CFR

2010-04-01

... device includes the esophageal dilator; tracheal bistour (a long, narrow surgical knife); tracheal dilator; tracheal hook; laryngeal injection set; laryngeal knife; laryngeal saw; laryngeal trocar...; wire ear loop; microrule; mirror; mobilizer; ear, nose, and throat punch; ear, nose and throat knife...

Comparison between intravenous paracetamol and fentanyl for intraoperative and postoperative pain relief in dilatation and evacuation: Prospective, randomized interventional trial.

PubMed

Ali, Muhammad Asghar; Shamim, Faisal; Chughtai, Shakaib

2015-01-01

Dilatation and Evacuation procedure involves pain, for which pain control measures need to be undertaken. The purpose of this study was to compare paracetamol with fentanyl for pain relief in dilatation and curettage procedures. Sixty female patients were randomly included during the period from March 1, 2012 to February 28, 2013. All patients had received oral midazolam 7.5 mg as a premedication 30 min before procedure in the ward. Group P had received intravenous (IV) paracetamol 15 mg/kg in the waiting area of the operating room 15 min before starting the procedure. Group F had received IV fentanyl 2 ug/kg/min at induction of anesthesia. Pain scores on a numerical rating scale at 5, 15, and 30 min intervals after surgery were recorded. Mild pain was commonly observed in both groups, an insignificant difference between groups. The study demonstrates the usefulness of IV paracetamol which may be as effective as fentanyl in dilation and curettage procedures.

Actinomyces canaliculitis and its surgical treatment.

PubMed

Yuksel, Dilek; Hazirolan, Dicle; Sungur, Gulten; Duman, Sunay

2012-04-01

The objective of this article is to describe four rare cases of Actinomyces israelii canaliculitis and their surgical treatment in a case series consisting of four cases of Actinomyces israelii canaliculitis. Patient charts were reviewed retrospectively. All four patients presented with epiphora, recurrent conjunctivitis, swelling around the superior canaliculus, and mucopurulent punctal discharge persisting despite medical treatments. Two patients with large canalicular dilation were treated with canaliculoplasty and the other two patients with minimal canalicular dilation were treated with one-snip punctoplasty. The specimens that were evacuated were sent for microbiological and histopathological examinations. The results showed that Actinomyces israelii was isolated in all patients. After medical and surgical treatment, the patients experienced resolution of signs and symptoms. The disease did not recur during the 2-4-year follow-up period. In conclusion Canaliculoplasty with canalicular intubation and one-snip punctoplasty may be safe and efficacious techniques in largely dilated canaliculum and mildly dilated canaliculum, respectively, with no demonstrable risk of post-treatment epiphora in patients with Actinomyces canaliculitis.

Management of infected urethral diverticulum with urethral dilation.

PubMed

Lazarou, George; Andrikopoulou, Maria; Cho, Sylvia

2015-01-01

Urethral diverticula are rare but underdiagnosed entities that may cause a variety of urinary and pelvic symptoms in women. Management can be very challenging, especially in cases of chronic infection. A 69-year-old gravida 4, para 2 woman with a history of type 2 diabetes and hypothyroidism presented with long history of a painful midline 3-cm suburethral cystic mass, recurrent urinary tract infections, dysuria, dyspareunia, and incomplete voiding. The diagnosis was consistent with an infected urethral diverticulum unresponsive to multiple courses of oral antibiotics. Given the patient's comorbidities and the persistence of infection of the diverticulum, conservative treatment with urethral dilation was performed before surgical treatment. Urethral dilation successfully alleviated the patient's symptoms; the surgical treatment was not ultimately required, and the patient continues to be completely asymptomatic well over 17 months later. We present a unique case of infected urethral diverticulum, which was conservatively treated with dilatation and resulted in resolution of all symptoms, and there is no need for further surgical management.

Mitral annulus size links ventricular dilatation to functional mitral regurgitation.

PubMed

Popović, Zoran B; Martin, Maureen; Fukamachi, Kiyotaka; Inoue, Masahiro; Kwan, Jun; Doi, Kazuyoshi; Qin, Jian Xin; Shiota, Takahiro; Garcia, Mario J; McCarthy, Patrick M; Thomas, James D

2005-09-01

We compared the impact of annulus size and valve deformation (tethering) on mitral regurgitation in the animal dilated cardiomyopathy model, and assessed if acute left ventricular volume changes affect mitral annulus dimensions. We performed 3-dimensional echocardiography in 30 open-chest dogs with pacing-induced cardiomyopathy. Mitral annulus area was calculated from its two orthogonal diameters, whereas valve tethering was quantified by valve tenting area measurement. Mitral valve regurgitant volume showed the highest correlation with annulus area (r = 0.64, P < .001), left atrial volume (r = 0.40, P < .01), and left ventricular end-diastolic volume (r = 0.37, P < .01). Regurgitant volume showed poorer correlation with valve tethering in both septolateral and intercommissural planes (r = 0.35 and r = 0.31, P < .05 for both). Annulus dimensions correlated with acute changes of left ventricular end-diastolic volume (r = 0.68, P = .002). Mitral annulus dilation is the strongest predictor of functional mitral regurgitation in this animal dilated cardiomyopathy model.

Landmark lecture: Perloff lecture: Tribute to Professor Joseph Kayle Perloff and lessons learned from him: aortopathy in adults with CHD.

PubMed

Niwa, Koichiro

2017-12-01

Marfan syndrome, bicuspid aortic valve, and/or coarctation of the aorta are associated with medial abnormalities of the ascending aortic or para-coarctation aorta. Medial abnormalities in the ascending aorta are prevalent in other type of patients with a variety of CHDs such as single ventricle, persistent truncus arteriosus, transposition of the great arteries, hypoplastic left heart syndrome, and tetralogy of Fallot, encompassing a wide age range and may predispose to dilatation, aneurysm, and rapture necessitating aortic valve and root surgery. These CHDs exhibit ongoing dilatation of the aortic root and reduced aortic elasticity and increased aortic stiffness that may relate to intrinsic properties of the aortic root. These aortic dilatation and increased stiffness can induce aortic aneurysm, rapture of the aorta, and aortic regurgitation, but also provoke left ventricular hypertrophy, reduced coronary artery flow, and left ventricular failure. Therefore, a new clinical entity can be used to call this association of aortic pathophysiological abnormality, aortic dilation, and aorto-left ventricular interaction - "aortopathy".

Comparison of implosion core metrics: A 10 ps dilation X-ray imager vs a 100 ps gated microchannel plate [Comparison of implosion core shape observations, 10 ps dilation X-ray imager vs 100 ps gated microchannel plate

DOE PAGES

Nagel, S. R.; Benedetti, L. R.; Bradley, D. K.; ...

2016-08-05

The dilation x-ray imager (DIXI) is a high-speed x-ray framing camera that uses the pulse-dilation technique to achieve a temporal resolution of less than 10 ps. This is a 10× improvement over conventional framing cameras currently employed on the National Ignition Facility (NIF) (100 ps resolution), and otherwise only achievable with 1D streaked imaging. A side effect of the dramatically reduced gate width is the comparatively lower detected signal level. Therefore we implement a Poisson noise reduction with non-local principal component analysis method to improve the robustness of the DIXI data analysis. Furthermore, we present results on ignition-relevant experiments atmore » the NIF using DIXI. In particular we focus on establishing that/when DIXI gives reliable shape metrics (P 0, P 2 and P 4 Legendre modes, and their temporal evolution/swings).« less

Comparison of implosion core metrics: A 10 ps dilation X-ray imager vs a 100 ps gated microchannel plate [Comparison of implosion core shape observations, 10 ps dilation X-ray imager vs 100 ps gated microchannel plate

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

Nagel, S. R.; Benedetti, L. R.; Bradley, D. K.

The dilation x-ray imager (DIXI) is a high-speed x-ray framing camera that uses the pulse-dilation technique to achieve a temporal resolution of less than 10 ps. This is a 10× improvement over conventional framing cameras currently employed on the National Ignition Facility (NIF) (100 ps resolution), and otherwise only achievable with 1D streaked imaging. A side effect of the dramatically reduced gate width is the comparatively lower detected signal level. Therefore we implement a Poisson noise reduction with non-local principal component analysis method to improve the robustness of the DIXI data analysis. Furthermore, we present results on ignition-relevant experiments atmore » the NIF using DIXI. In particular we focus on establishing that/when DIXI gives reliable shape metrics (P 0, P 2 and P 4 Legendre modes, and their temporal evolution/swings).« less

Asymmetric dilatation of virchow-robin space in unilateral internal carotid artery steno-occlusive disease.

PubMed

Park, Ah Young; Chung, Tae-Sub; Suh, Sang Hyun; Choi, Hyun Seok; Lee, Yun Hee

2011-01-01

The cause of abnormal Virchow-Robin space (VRS) dilatation is still unclear. The purpose of this study was to test the hypothesis that chronic ischemia from the unilateral significant internal carotid artery (ICA) stenosis is related to asymmetric VRS dilatation. We recruited 78 patients with severe unilateral ICA stenosis (>70%) diagnosed by magnetic resonance angiography, computed tomography angiography, or digital subtraction angiography and retrospectively reviewed 3-T brain magnetic resonance images. All VRSs on bilateral cerebral high-convexity areas were scaled into 4 grades. We analyzed the difference of VRS grades between bilateral hemispheres and the correlation between VRS grade and severity of ICA stenosis and the patient's age. The VRS grades on the ipsilateral hemisphere were higher than those on the contralateral and were positively correlated with the degree of ICA stenosis. The bilateral VRS grades and the patients' ages were positively correlated. Our results suggest that severe ICA steno-occlusive disease would be related with abnormal VRS dilatation.

The analysis and modelling of dilatational terms in compressible turbulence

NASA Technical Reports Server (NTRS)

Sarkar, S.; Erlebacher, G.; Hussaini, M. Y.; Kreiss, H. O.

1991-01-01

It is shown that the dilatational terms that need to be modeled in compressible turbulence include not only the pressure-dilatation term but also another term - the compressible dissipation. The nature of these dilatational terms in homogeneous turbulence is explored by asymptotic analysis of the compressible Navier-Stokes equations. A non-dimensional parameter which characterizes some compressible effects in moderate Mach number, homogeneous turbulence is identified. Direct numerical simulations (DNS) of isotropic, compressible turbulence are performed, and their results are found to be in agreement with the theoretical analysis. A model for the compressible dissipation is proposed; the model is based on the asymptotic analysis and the direct numerical simulations. This model is calibrated with reference to the DNS results regarding the influence of compressibility on the decay rate of isotropic turbulence. An application of the proposed model to the compressible mixing layer has shown that the model is able to predict the dramatically reduced growth rate of the compressible mixing layer.

The analysis and modeling of dilatational terms in compressible turbulence

NASA Technical Reports Server (NTRS)

Sarkar, S.; Erlebacher, G.; Hussaini, M. Y.; Kreiss, H. O.

1989-01-01

It is shown that the dilatational terms that need to be modeled in compressible turbulence include not only the pressure-dilatation term but also another term - the compressible dissipation. The nature of these dilatational terms in homogeneous turbulence is explored by asymptotic analysis of the compressible Navier-Stokes equations. A non-dimensional parameter which characterizes some compressible effects in moderate Mach number, homogeneous turbulence is identified. Direct numerical simulations (DNS) of isotropic, compressible turbulence are performed, and their results are found to be in agreement with the theoretical analysis. A model for the compressible dissipation is proposed; the model is based on the asymptotic analysis and the direct numerical simulations. This model is calibrated with reference to the DNS results regarding the influence of compressibility on the decay rate of isotropic turbulence. An application of the proposed model to the compressible mixing layer has shown that the model is able to predict the dramatically reduced growth rate of the compressible mixing layer.

Associations of Initial Society for Fetal Urology Grades and Urinary Tract Dilatation Risk Groups with Clinical Outcomes in Patients with Isolated Prenatal Hydronephrosis.

PubMed

Braga, Luis H; McGrath, Melissa; Farrokhyar, Forough; Jegatheeswaran, Kizanee; Lorenzo, Armando J

2017-03-01

There are limited comparative data on the predictive value of the 2 most commonly used classification systems, that is SFU (Society for Fetal Urology) hydronephrosis grades and urinary tract dilatation risk groups, in regard to the future risk of surgical intervention and the development of febrile urinary tract infection. We explored this topic in infants with isolated hydronephrosis. After screening 938 patients with prenatal hydronephrosis from 2009 to 2016 we selected 322 patients with ureteropelvic junction obstruction-like hydronephrosis for study. Hydronephrosis grades were prospectively collected at baseline, surgery and last followup. Gender, circumcision status, antibiotic prophylaxis and renal pelvis anteroposterior diameter were captured. The primary outcome was pyeloplasty and the development of febrile urinary tract infection. Comparative analyses between SFU grades/urinary tract dilatation groups and the primary outcome were performed with the Fisher exact and log rank tests. Mean ± SD age at presentation was 3.3 ± 2.6 months and mean followup was 22 ± 19 months. Pyeloplasty was performed in 32% of patients with SFU III/IV vs 31% with urinary tract dilatation 2/3. The rate of febrile urinary tract infection in patients with SFU III/IV was similar to that in those with urinary tract dilatation group 2/3 (8% vs 10%). Children with SFU III/IV showed a significantly higher rate of surgery than those with SFU I/II (32% vs 2%, p <0.01). Similar findings were seen when using urinary tract dilatation groups to compare patients at low risk (1) vs moderate/high risk (2/3). Both grading systems equally allowed for proper risk stratification and prediction of clinical outcomes based on baseline ultrasound. They correctly separated most infants who underwent surgery or in whom febrile urinary tract infection developed from those who could be treated nonsurgically. Use of the new urinary tract dilatation classification should not affect how families of children with isolated hydronephrosis are counseled regarding surgical intervention and the risk of febrile urinary tract infection. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Nonmydriatic ultrawide field retinal imaging compared with dilated standard 7-field 35-mm photography and retinal specialist examination for evaluation of diabetic retinopathy.

PubMed

Silva, Paolo S; Cavallerano, Jerry D; Sun, Jennifer K; Noble, Jason; Aiello, Lloyd M; Aiello, Lloyd Paul

2012-09-01

To compare nonmydriatic stereoscopic Optomap ultrawide field images with dilated stereoscopic Early Treatment Diabetic Retinopathy Study 7-standard field 35-mm color 30-degree fundus photographs (ETDRS photography) and clinical examination for determining diabetic retinopathy (DR) and diabetic macular edema (DME) severity. Single-site, prospective, comparative, instrument validation study. One hundred three diabetic patients (206 eyes) representing the full spectrum of DR severity underwent nonmydriatic ultrawide field 100-degree and 200-degree imaging, dilated ETDRS photography, and dilated fundus examination by a retina specialist. Two independent readers graded images to determine DR and DME severity. A third masked retina specialist adjudicated discrepancies. Based on ETDRS photography (n = 200), the results were as follows: no DR (n = 25 eyes [12.5%]), mild nonproliferative DR (NPDR; 47 [23.5%]), moderate NPDR (61 [30.5%]), severe NPDR (11 [5.5%]), very severe NPDR (3 [1.5%]), and proliferative DR (52 [2.5%]). One (0.5%) eye was ungradable and 6 eyes did not complete ETDRS photography. No DME was found in 114 eyes (57.0%), DME was found in 28 eyes (14.0%), and clinically significant DME was found in 47 eyes (23.5%), and 11 (5.5%) eyes were ungradable. Exact DR severity agreement between ultrawide field 100-degree imaging and ETDRS photography occurred in 84%, with agreement within 1 level in 91% (K(W) = 0.85; K = 0.79). Nonmydriatic ultrawide field images exactly matched clinical examination results for DR in 70% and were within 1 level in 93% (K(W) = 0.71; K = 0.61). Nonmydriatic ultrawide field imaging acquisition time was less than half that of dilated ETDRS photography (P < .0001). Nonmydriatic ultrawide field images compare favorably with dilated ETDRS photography and dilated fundus examination in determining DR and DME severity; however, they are acquired more rapidly. If confirmed in broader diabetic populations, nonmydriatic ultrawide field imaging may prove to be beneficial in DR evaluation in research and clinical settings. Copyright © 2012 Elsevier Inc. All rights reserved.

Refining paracervical block techniques for pain control in first trimester surgical abortion: a randomized controlled noninferiority trial.

PubMed

Renner, Regina-Maria; Edelman, Alison B; Nichols, Mark D; Jensen, Jeffrey T; Lim, Jeong Y; Bednarek, Paula H

2016-11-01

Our objective was to evaluate two different aspects of the paracervical block (PCB) technique for first trimester surgical abortion, to compare a 3-min wait prior to cervical dilation to no wait and to compare four-site with two-site injection. We conducted two consecutive randomized, single-blinded noninferiority trials. In the first trial, women <11 weeks gestational age received a 20-mL 1% buffered lidocaine four-site PCB with either a 3-min wait between PCB injection and dilation or no wait. In the second trial, we compared a four-site with a two-site PCB. We evaluated dilation pain [100-mm visual analogue scale (VAS)] as the primary outcome. Secondary outcomes included pain at additional time points, anxiety, satisfaction and adverse events. Both trials fully enrolled (total n=332). Results were inconclusive as to whether no wait was noninferior to waiting 3-min prior to cervical dilation for dilation pain [VAS: 63 mm (SD, 24 mm) vs. 56 mm (SD, 32mm)] and as to whether a two-site PCB was noninferior to a four-site block [VAS: 68 mm (SD, 21 mm) vs. 60 mm (SD, 30 mm)]. Noninferiority analysis was inconclusive because the confidence interval of the mean pain score difference between groups included the predefined inferiority margin of 13-mm pain difference. Superiority analysis showed the four-site PCB to be superior to the two-site PCB. It remained inconclusive whether a 3-min wait time between PCB and cervical dilation provides noninferior pain control for first trimester surgical abortion. However, a four-site PCB appeared to be superior to a two-site PCB. It remained inconclusive whether a 3-min wait time between PCB and cervical dilation or using a two-site instead of a four-site PCB provided noninferior pain control for first trimester surgical abortion. This study did not assess whether the combination of the two separate factors provides additive benefit. Copyright © 2016 Elsevier Inc. All rights reserved.

Percutaneous Dilational Tracheotomy in Solid-Organ Transplant Recipients.

PubMed

Ozdemirkan, Aycan; Ersoy, Zeynep; Zeyneloglu, Pinar; Gedik, Ender; Pirat, Arash; Haberal, Mehmet

2015-11-01

Solid-organ transplant recipients may require percutaneous dilational tracheotomy because of prolonged mechanical ventilation or airway issues, but data regarding its safety and effectiveness in solid-organ transplant recipients are scarce. Here, we evaluated the safety, effectiveness, and benefits in terms of lung mechanics, complications, and patient comfort of percutaneous dilational tracheotomy in solid-organ transplant recipients. Medical records from 31 solid-organ transplant recipients (median age of 41.0 years [interquartile range, 18.0-53.0 y]) who underwent percutaneous dilational tracheotomy at our hospital between January 2010 and March 2015 were analyzed, including primary diagnosis, comorbidities, duration of orotracheal intubation and mechanical ventilation, length of intensive care unit and hospital stays, the time interval between transplant to percutaneous dilational tracheotomy, Acute Physiology and Chronic Health Evaluation II score, tracheotomy-related complications, and pulmonary compliance and ratio of partial pressure of arterial oxygen to fraction of inspired oxygen. The median Acute Physiology and Chronic Health Evaluation II score on admission was 24.0 (interquartile range, 18.0-29.0). The median interval from transplant to percutaneous dilational tracheotomy was 105.5 days (interquartile range, 13.0-2165.0 d). The only major complication noted was left-sided pneumothorax in 1 patient. There were no significant differences in ratio of partial pressure of arterial oxygen to fraction of inspired oxygen before and after procedure (170.0 [interquartile range, 102.2-302.0] vs 210.0 [interquartile range, 178.5-345.5]; P = .052). However, pulmonary compliance results preprocedure and postprocedure were significantly different (0.020 L/cm H2O [interquartile range, 0.015-0.030 L/cm H2O] vs 0.030 L/cm H2O [interquartile range, 0.020-0.041 L/cm H2O); P = .001]). Need for sedation significantly decreased after tracheotomy (from 17 patients [54.8%] to 8 patients [25.8%]; P = .004]). Percutaneous dilational tracheotomy with bronchoscopic guidance is an efficacious and safe technique for maintaining airways in solidorgan transplant recipients who require prolonged mechanical ventilation, resulting in possible improvements in ventilatory mechanics and patient comfort.

Subclassification of left ventricular hypertrophy based on dilation stratifies coronary artery disease patients with distinct risk.

PubMed

Huang, Bao-Tao; Peng, Yong; Liu, Wei; Zhang, Chen; Huang, Fang-Yang; Wang, Peng-Ju; Zuo, Zhi-Liang; Liao, Yan-Biao; Chai, Hua; Li, Qiao; Zhao, Zhen-Gang; Luo, Xiao-Lin; Ren, Xin; Huang, Kai-Sen; Meng, Qing-Tao; Chen, Chi; Huang, De-Jia; Chen, Mao

2014-10-01

A new 4-tired classification of left ventricular hypertrophy (LVH) based on LV concentricity and dilation has been proposed; however, the association between the new categorization of LV geometry and outcomes in patients with coronary artery disease (CAD) is still unknown. All the 2297 patients with CAD included underwent echocardiographic examination prior to discharge. Left ventricular mass (LVM) was calculated, and left ventricular end-diastolic volume (EDV) was indexed by body surface area (BSA). Study cohort was divided into five groups according to LV geometry: (i) eccentric nondilated LVH (normal LVM/EDV((2/3)) and EDV/BSA) (n = 129); (ii) eccentric dilated LVH (normal LVM/EDV((2/3)) with increased EDV/BSA) (n = 222); (iii) concentric nondilated LVH (increased LVM/EDV((2/3)) with normal EDV/BSA) (n = 441); (iv) concentric dilated LVH (increased LVM/EDV((2/3)) and EDV/BSA) (n = 118); and (v) normal LV mass (n = 1387). Dilated LVH was associated with a higher event rates of all-cause death (eccentric 13·1% vs. 3·1%; concentric 13·6% vs. 8·4%) and composite events (eccentric: 17·6% vs. 5·4%; concentric: 18·6% vs. 12·7%) compared with nondilated LVH. While eccentric nondilated LVH had comparable risk for adverse outcomes compared with normal LV mass (all-cause death: relative risk (RR) 0·68, 95% confidential interval (CI) 0·25-1·85; composite events: RR 0·75, 95% CI 0·36-1·58). Cox regression analyses showed that eccentric dilated LVH had the highest propensity to all-cause death (adjusted hazard ratio [aHR] 2·752 [95% CI 1·749-4·328], P < 0·001) and composite events (aHR 2·462 [95% CI 1·688-3·592], P < 0·001). In patients with CAD, dilated LVH and nondilated LVH provide distinct prognostic information. Eccentric nondilated LVH does not predict adverse outcomes. © 2014 Stichting European Society for Clinical Investigation Journal Foundation.

Aneurysm of the right ventricular outflow following bovine valved venous conduit insertion.

PubMed

Boudjemline, Younes; Bonnet, Damien; Agnoletti, Gabriella; Vouhé, Pascal

2003-01-01

A case of aneurysm of the right ventricular outflow tract is described after repair of tetralogy of Fallot using a Contegra supported conduit. Angiograms revealed that the aneurysm was located between the ventricular anastomosis and the proximal ring of the conduit confirming echocardiographic data. Because the conduit between the rings was not dilated, the valve was perfectly functioning. Pulmonary anastomosis was severely stenosed explaining the dilatation seen below. Conduit replacement with resection of the aneurysmal part of the failing conduit was performed. Supported conduits do not eliminate the risk of secondary dilatation below the artificial ring but preserve valvular function.

Minimally invasive per-catheter occlusion and dilation procedures for congenital cardiovascular abnormalities in dogs.

PubMed

Tobias, Anthony H; Stauthammer, Christopher D

2010-07-01

With ever-increasing sophistication of veterinary cardiology, minimally invasive per-catheter occlusion and dilation procedures for the treatment of various congenital cardiovascular abnormalities in dogs have become not only available, but mainstream. Much new information about minimally invasive per-catheter patent ductus arteriosus occlusion has been published and presented during the past few years. Consequently, patent ductus arteriosus occlusion is the primary focus of this article. Occlusion of other less common congenital cardiac defects is also briefly reviewed. Balloon dilation of pulmonic stenosis, as well as other congenital obstructive cardiovascular abnormalities is discussed in the latter part of the article.

Reduction Corporoplasty

PubMed Central

Hakky, Tariq S.; Martinez, Daniel; Yang, Christopher; Carrion, Rafael E.

2015-01-01

Objective Here we present the first video demonstration of reduction corporoplasty in the management of phallic disfigurement in a 17 year old man with a history sickle cell disease and priapism. Introduction Surgical management of aneurysmal dilation of the corpora has yet to be defined in the literature. Materials and Methods: We preformed bilateral elliptical incisions over the lateral corpora as management of aneurysmal dilation of the corpora to correct phallic disfigurement. Results The patient tolerated the procedure well and has resolution of his corporal disfigurement. Conclusions Reduction corporoplasty using bilateral lateral elliptical incisions in the management of aneurysmal dilation of the corpora is a safe an feasible operation in the management of phallic disfigurement. PMID:26005988

Dilation and breakage dissipation of granular soils subjected to monotonic loading

NASA Astrophysics Data System (ADS)

Sun, Yifei; Xiao, Yang; Ji, Hua

2016-12-01

Dilation and breakage energy dissipation of four different granular soils are investigated by using an energy balance equation. Due to particle breakage, the dilation curve does not necessarily pass through the origin of coordinates. Breakage energy dissipation is found to increase significantly at the initial loading stage and then gradually become stabilised. The incremental dissipation ratio between breakage energy and plastic work exhibits almost independence of the confining pressure. Accordingly, a plastic flow rule considering the effect of particle breakage is suggested. The critical state friction angle is found to be a combination of the basic friction between particles and the friction contributed by particle breakage.

Massive multicystic dilatation of the uterine wall with myometrial venous thrombosis during pregnancy.

PubMed

Uotila, J; Dastidar, P; Martikainen, P; Kirkinen, P

2004-09-01

We present a pregnancy complicated by multicystic dilatation of the uterine wall during the second trimester, leading to massive uterine distension, anemia and preterm Cesarean section. The cystic changes detected by ultrasound and magnetic resonance imaging involved the whole uterine wall surrounding the entire amniotic cavity. Histopathological examination revealed the benign nature of the cystic changes, which represented dilated and thrombosed venous lacunae. Disturbed venous drainage, combined with local thrombosis, was likely to have led to the collection of a large volume of blood in the uterine wall and the subsequent multicystic change of the myometrium. Copyright 2004 ISUOG

Varied Presentation of Congenital Segmental Dilatation of the Intestine in Neonates: Report of Three Cases

PubMed Central

Rai, Binod Kumar; Mirza, Bilal; Hashim, Imran; Saleem, Muhammad

2016-01-01

Congenital segmental dilatation (CSD) of the intestine is a rare developmental anomaly characterized by sharply demarcated dilatation of a gastrointestinal segment and may present with intestinal obstruction. We report three cases of CSD of the intestine in neonates with varied presentation. First patient was mistaken as pneumoperitoneum on abdominal radiograph, which led to initial abdominal drain placement. The 2nd patient was a case of anorectal malformation associated with congenital pouch colon (CPC) and CSD of ileum; and the third case presented as neonatal intestinal obstruction and found to have CSD of ileum. All the patients were successfully managed in our department. PMID:27896163

Surgical treatment of recurrent dacryocystitis secondary to cystic dilatation of the nasolacrimal duct in a dog.

PubMed

Lussier, Bertrand; Carrier, Michel

2004-01-01

A 3-year-old, castrated male golden retriever was presented for evaluation of recurrent ocular discharge of 4 months' duration from the left eye. Dacryocystorhinography was performed and demarcated a cystic dilatation of the left nasolacrimal duct with obstruction of the duct distal to the cystic cavity. Surgical exploration of the left maxillary sinus was performed to confirm the diagnosis and reestablish drainage into the nasal cavity. Recovery was uneventful, and the dog has been asymptomatic for >36 months postoperatively. This report documents the third published case of surgical treatment for cystic dilatation of the nasolacrimal duct.

Modeling of Inhomogeneous Compressible Turbulence Using a Two-Scale Statistical Theory

NASA Technical Reports Server (NTRS)

Hamba, Fujihiro

1996-01-01

Turbulence modeling plays an important role in the study of high-speed flows in engineering and aerodynamic problems; they include flows in supersonic combustion engines and over hypersonic transport aircraft. The enhancement of the kinetic energy dissipation by the dilatational terms is one of the typical compressibility effects. Zeman (1990) and Sarkar et al. (1991) proposed that the dilatation dissipation is proportional to the solenoidal dissipation and is a function of the turbulent Mach number. Sarkar (1992) also modeled the pressure-dilatation correlation using the turbulent Mach number. Zeman (1991) related the correlation to the rate of change of the pressure variance.

21 CFR 870.1310 - Vessel dilator for percutaneous catheterization.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Vessel dilator for percutaneous catheterization. 870.1310 Section 870.1310 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Diagnostic Devices § 870.1310...

21 CFR 870.1310 - Vessel dilator for percutaneous catheterization.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vessel dilator for percutaneous catheterization. 870.1310 Section 870.1310 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Diagnostic Devices § 870.1310...

21 CFR 874.3900 - Nasal dilator.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Nasal dilator. 874.3900 Section 874.3900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES... nasal airflow. The device decreases airway resistance and increases nasal airflow. The external nasal...

21 CFR 874.3900 - Nasal dilator.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nasal dilator. 874.3900 Section 874.3900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES... nasal airflow. The device decreases airway resistance and increases nasal airflow. The external nasal...

Ascending aorta dilatation in patients with bicuspid aortic valve stenosis: a prospective CMR study.

PubMed

Rossi, Alexia; van der Linde, Denise; Yap, Sing Chien; Lapinskas, Thomas; Kirschbaum, Sharon; Springeling, Tirza; Witsenburg, Maarten; Cuypers, Judith; Moelker, Adriaan; Krestin, Gabriel P; van Dijk, Arie; Johnson, Mark; van Geuns, Robert-Jan; Roos-Hesselink, Jolien W

2013-03-01

The aim of this study was to evaluate the natural progression of aortic dilatation and its association with aortic valve stenosis (AoS) in patients with bicuspid aortic valve (BAV). Prospective study of aorta dilatation in patients with BAV and AoS using cardiac magnetic resonance (CMR). Aortic root, ascending aorta, aortic peak velocity, left ventricular systolic and diastolic function and mass were assessed at baseline and at 3-year follow-up. Of the 33 enrolled patients, 5 needed surgery, while 28 patients (17 male; mean age: 31 ± 8 years) completed the study. Aortic diameters significantly increased at the aortic annulus, sinus of Valsalva and tubular ascending aorta levels (P < 0.050). The number of patients with dilated tubular ascending aortas increased from 32 % to 43 %. No significant increase in sino-tubular junction diameter was observed. Aortic peak velocity, ejection fraction and myocardial mass significantly increased while the early/late filling ratio significantly decreased at follow-up (P < 0.050). The progression rate of the ascending aorta diameter correlated weakly with the aortic peak velocity at baseline (R (2) = 0.16, P = 0.040). BAV patients with AoS showed a progressive increase of aortic diameters with maximal expression at the level of the tubular ascending aorta. The progression of aortic dilatation correlated weakly with the severity of AoS.

Canine gastric dilatation/volvulus syndrome in a veterinary critical care unit: 295 cases (1986-1992).

PubMed

Brockman, D J; Washabau, R J; Drobatz, K J

1995-08-15

Two hundred ninety-five case records were included in an analysis of dogs treated by a standardized protocol for gastric dilatation/volvulus syndrome between 1986 and 1992. A breed predisposition was demonstrated for Great Danes, German Shepherd Dogs, large mixed-breed dogs, and Standard Poodles. One hundred and ninety-three dogs had gastric dilatation and volvulus (GDV) confirmed at surgery, 66 had simple gastric dilatation (GD), and 36 others had gastric dilatation but volvulus could not be proved or disproved (GD +/- V). Among dogs with GDV, the fatality rate was 15% (29/193). Twenty-six (13.5%) dogs with GDV underwent partial gastrectomy, and 8 (31%) died or were subsequently euthanatized. In comparing the group of dogs with GDV that survived to those that died, there were no statistical differences in the age of dog, time between onset of clinical signs and admission, time from admission to surgery, or duration of anesthesia. Cardiac arrhythmias were detected in 40% (78/193) of the dogs with GDV. There also was no statistical correlation between development of a cardiac arrhythmia and outcome in dogs with GDV. The causes of death in dogs with GDV were multiple and varied; presumed gastric necrosis was a common reason for intraoperative euthanasia (11 dogs). Among dogs with GD or GD +/- V, the fatality rate was 0.9% (1/102).

Modeling and study of the mechanism of dilated cardiomyopathy using induced pluripotent stem cells derived from individuals with Duchenne muscular dystrophy.

PubMed

Lin, Bo; Li, Yang; Han, Lu; Kaplan, Aaron D; Ao, Ying; Kalra, Spandan; Bett, Glenna C L; Rasmusson, Randall L; Denning, Chris; Yang, Lei

2015-05-01

Duchenne muscular dystrophy (DMD) is caused by mutations in the dystrophin gene (DMD), and is characterized by progressive weakness in skeletal and cardiac muscles. Currently, dilated cardiomyopathy due to cardiac muscle loss is one of the major causes of lethality in late-stage DMD patients. To study the molecular mechanisms underlying dilated cardiomyopathy in DMD heart, we generated cardiomyocytes (CMs) from DMD and healthy control induced pluripotent stem cells (iPSCs). DMD iPSC-derived CMs (iPSC-CMs) displayed dystrophin deficiency, as well as the elevated levels of resting Ca(2+), mitochondrial damage and cell apoptosis. Additionally, we found an activated mitochondria-mediated signaling network underlying the enhanced apoptosis in DMD iPSC-CMs. Furthermore, when we treated DMD iPSC-CMs with the membrane sealant Poloxamer 188, it significantly decreased the resting cytosolic Ca(2+) level, repressed caspase-3 (CASP3) activation and consequently suppressed apoptosis in DMD iPSC-CMs. Taken together, using DMD patient-derived iPSC-CMs, we established an in vitro model that manifests the major phenotypes of dilated cardiomyopathy in DMD patients, and uncovered a potential new disease mechanism. Our model could be used for the mechanistic study of human muscular dystrophy, as well as future preclinical testing of novel therapeutic compounds for dilated cardiomyopathy in DMD patients. © 2015. Published by The Company of Biologists Ltd.

Tocolysis in women with advanced preterm labor: a secondary analysis of a randomized clinical trial.

PubMed

Klauser, Chad K; Briery, Christian M; Tucker, Ann R; Martin, Rick W; Magann, Everett F; Chauhan, Suneet P; Morrison, John C

2016-03-01

To compare the efficacy of tocolytic treatment with indomethacin (I), magnesium sulfate (M) and nifedipine (N) for acute tocolysis in women with advanced cervical dilation (4-6 cm). A single center, randomized trial was carried out involving patients in preterm labor (cervix 1-6 cm). Secondary analysis of women with advanced cervical dilation (cervix 4-6 cm) at 24-32 weeks' gestation who received intravenous M, oral N or I suppositories comprised this study population. Over 38 months, 92 women with advanced cervical dilation were randomized to one tocoloytic type. Days gained in utero (11.7) and percent remaining undelivered at 48 h (60.8%), 72 h (53.1%) and >7 days (38.3%) were similar regardless of tocolytic employed (p = 0.923, 0.968, 0.791, 0.802, respectively). Likewise, gestational age at delivery (30.7 ± 3.2) was similar between groups (p = 0.771). Finally, neonatal statistics were not different when stratified by tocolytic treatment. There were no statistical differences between tocolytics in treating women with advanced cervical dilation. All offered significant days gained in utero after therapy, a high percentage remaining undelivered after 48 or 72 h and after 7 days. It would appear from data that there may be advantages to tocolytic treatment even in women with advanced cervical dilation.

Study of phenotype evolution during childhood in Marfan syndrome to improve clinical recognition.

PubMed

Stheneur, Chantal; Tubach, Florence; Jouneaux, Marlène; Roy, Carine; Benoist, Gregoire; Chevallier, Bertrand; Boileau, Catherine; Jondeau, Guillaume

2014-03-01

Because diagnosis of Marfan syndrome is difficult during infancy, we used a large cohort of children to describe the evolution of the Marfan syndrome phenotype with age. Two hundred and fifty-nine children carrying an FBN1 gene mutation and fulfilling Ghent criteria were compared with 474 non-Marfan syndrome children. Prevalence of skeletal features changed with aging: prevalence of pectus deformity increased from 43% at 0-6 years to 62% at 15-17 years, wrist signs increased from 28 to 67%, and scoliosis increased from 16 to 59%. Hypermobility decreased from 67 to 47% and pes planus decreased from 73 to 65%. Striae increased from 2 to 84%. Prevalence of ectopia lentis remained stable, varying from 66 to 72%, similar to aortic root dilatation (varying from 75 to 80%). Aortic root dilatation remained stable during follow-up in this population receiving β-blocker therapy. When comparing Marfan syndrome children with non-Marfan syndrome children, height appeared to be a simple and discriminant criterion when it was >3.3 SD above the mean. Ectopia lentis and aortic dilatation were both similarly discriminating. Ectopia lentis and aortic dilatation are the best-discriminating features, but height remains a simple discriminating variable for general practitioners when >3.3 SD above the mean. Mean aortic dilatation remains stable in infancy when children receive a β-blocker.

A review of techniques of induced abortion.

PubMed

Hepburn, S

1981-04-01

Various techniques are available for inducing abortion. Evacuation of the uterus through the vagina is generally the preferred method in first trimester pregnancies. Dilation of the cervical canal by inserting rod dilators or laminaria tents allows the withdrawal of the fetus. Suction procedures (vacuum aspiration, uterine aspiration, or suction curettage) are possible since the decidua are separable from the basal layer of endometrium. This removal by force does not damage other maternal tissue. A cannula is introduced into the uterine cavity through the dilated cervix and its operator is then connected to a pump by way of a flexible tube which delivers negative pressure of about 600 mm of mercury. When the fetus is withdrawn, the uterus is felt to contract onto the cannula. The average time for this procedure is 5 minutes. Surgical curettage or dilatation and evacuation first dilates the cervical canal and then removes fetal parts and tissue from ovum forceps; a sharp curette does the rest. Anesthesia for these procedures may be general, local, or spinal. The techniques of menstrual regulation is used before pregnancy can be confirmed. However with the advent of the RIA test for the beta subunit of HCG this procedure is rarely indicated. Induction of premature labor is used in the later 1/2 of the second trimester and utilizes prostaglandins. Intraamniobor usually begins within 24 hours. Hysterotomy and hysterectomy are surgical procedures used in abortions.

Balloon expandable transcatheter aortic valve implantation with or without pre-dilation of the aortic valve - rationale and design of a multicenter registry (EASE-IT).

PubMed

Bramlage, Peter; Strauch, Justus; Schröfel, Holger

2014-11-18

In patients with severe calcific aortic stenosis, balloon aortic valvuloplasty (BAV) is routinely performed in order to pre-dilate the stenosed aortic valve prior to transcatheter aortic valve implantation (TAVI). Although pre-dilation is considered to be essential for the preparation of the valve landing zone, there is no clear evidence to support its clinical value. In contrast, BAV has been suggested to be linked to several complications. Notably, while preliminary evidence has supported the feasibility and safety of TAVI without pre-dilation, larger studies directly comparing the benefit/risk profile of TAVI in the presence and absence of pre-dilation are required. Therefore, a prospective, two-armed, multicenter registry (EASE-IT) was designed to obtain essential data concerning procedural success rates, adverse events, and mortality in a large cohort of patients undergoing transapical (TA)-TAVI using the Edwards SAPIEN 3 balloon expandable heart valves with and without pre-ballooning. Data provided by EASE-IT will be used to assess the relevance of BAV during the TAVI procedure and to investigate associations between patient characteristics and outcomes. Therefore, results obtained from the EASE-IT registry could contribute to reduced rates of TAVI-associated morbidity and mortality in patients with severe, calcific aortic stenosis. ClinicalTrials.gov Identifier: NCT02127580.

Reliability of automatic biometric iris recognition after phacoemulsification or drug-induced pupil dilation.

PubMed

Seyeddain, Orang; Kraker, Hannes; Redlberger, Andreas; Dexl, Alois K; Grabner, Günther; Emesz, Martin

2014-01-01

To investigate the reliability of a biometric iris recognition system for personal authentication after cataract surgery or iatrogenic pupil dilation. This was a prospective, nonrandomized, single-center, cohort study for evaluating the performance of an iris recognition system 2-24 hours after phacoemulsification and intraocular lens implantation (group 1) and before and after iatrogenic pupil dilation (group 2). Of the 173 eyes that could be enrolled before cataract surgery, 164 (94.8%) were easily recognized postoperatively, whereas in 9 (5.2%) this was not possible. However, these 9 eyes could be reenrolled and afterwards recognized successfully. In group 2, of a total of 184 eyes that were enrolled in miosis, a total of 22 (11.9%) could not be recognized in mydriasis and therefore needed reenrollment. No single case of false-positive acceptance occurred in either group. The results of this trial indicate that standard cataract surgery seems not to be a limiting factor for iris recognition in the large majority of cases. Some patients (5.2% in this study) might need "reenrollment" after cataract surgery. Iris recognition was primarily successful in eyes with medically dilated pupils in nearly 9 out of 10 eyes. No single case of false-positive acceptance occurred in either group in this trial. It seems therefore that iris recognition is a valid biometric method in the majority of cases after cataract surgery or after pupil dilation.

Gastric dilatation-volvulus syndrome in dogs.

PubMed

Monnet, Eric

2003-09-01

Gastric dilatation-volvulus is a medical and surgical emergency that principally affects large-breed dogs. Surgical treatment should be undertaken as soon as the patient has been stabilized with fluid therapy and decompression. A gastrectomy might be required if the stomach is becoming necrotic. A gastropexy is required to prevent recurrence.

The Universality of Time Dilation and Space Contraction.

ERIC Educational Resources Information Center

Daly, Lisa N.; Horton, George K.

1994-01-01

Describes the extended general physics course taught at Rutgers University. The course presents to students at the high school algebra level the topic of analyzing a particular thought experiment that yields the time dilation formula and subsequently space contraction, velocity addition, and other 20th-century physics concepts. (MVL)

Noise transmission by viscoelastic sandwich panels

NASA Technical Reports Server (NTRS)

Vaicaitis, R.

1977-01-01

An analytical study on low frequency noise transmission into rectangular enclosures by viscoelastic sandwich panels is presented. Soft compressible cores with dilatational modes and hard incompressible cores with dilatational modes neglected are considered as limiting cases of core stiffness. It is reported that these panels can effect significant noise reduction.

Omasal dilation and displacement in 4 Holstein dairy cows

PubMed Central

Bicalho, Rodrigo C.; Mayers, Heather M.; Cheong, Soon Hon; Rosa, Brielle V.; Guard, Charles L.

2009-01-01

Cases of omasal dilation and displacement in 4 dairy cows are described. The disease was initially diagnosed by a combination of history and clinical signs that included right-sided abdominal distension, rectal palpation, and decreased milk production. The condition was confirmed by laparotomy or necropsy. PMID:19436447

21 CFR 884.4260 - Hygroscopic Laminaria cervical dilator.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hygroscopic Laminaria cervical dilator. 884.4260 Section 884.4260 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... conical and expansible material made from the root of a seaweed (Laminaria digitata or Laminaria japonica...

The relativistic foundations of synchrotron radiation.

PubMed

Margaritondo, Giorgio; Rafelski, Johann

2017-07-01

Special relativity (SR) determines the properties of synchrotron radiation, but the corresponding mechanisms are frequently misunderstood. Time dilation is often invoked among the causes, whereas its role would violate the principles of SR. Here it is shown that the correct explanation of the synchrotron radiation properties is provided by a combination of the Doppler shift, not dependent on time dilation effects, contrary to a common belief, and of the Lorentz transformation into the particle reference frame of the electromagnetic field of the emission-inducing device, also with no contribution from time dilation. Concluding, the reader is reminded that much, if not all, of our argument has been available since the inception of SR, a research discipline of its own standing.

Segmental dilatation of sigmoid colon in a neonate: atypical presentation and histology.

PubMed

Mahadevaiah, Shubha Attibele; Panjwani, Poonam; Kini, Usha; Mohanty, Suravi; Das, Kanishka

2011-03-01

Segmental dilatation of the colon is a rare disorder of colonic motility in children, often presenting with severe constipation in older infants, children, and occasionally adults. It may mimic the commoner Hirschsprung disease clinicoradiologically but differs in that the ganglion cell morphology and distribution are typically normal in the colon. We report a neonate with segmental dilatation of the sigmoid colon who had an atypical clinical presentation and describe certain abnormalities in bowel histology (hypertrophied muscularis propria, nerve plexus, and ganglion cells located within the circular layer rather than the normal myenteric location), for the first time in the English literature. Copyright © 2011 Elsevier Inc. All rights reserved.

BENIGN IDIOPATHIC ESOPHAGEAL STRICTURE IN A LION ( PANTHERA LEO): DILATION BY AN ACHALASIA BALLOON.

PubMed

Ayala, Ignacio; Laredo, Francisco; Escobar; Alberca, Fernando

2018-03-01

A 1-yr old female lion ( Panthera leo) was referred with a 10-mo history of dysphagia for solid food (meat), episodic regurgitation, and poor weight gain. Esophagoscopy confirmed an esophagitis (midesophagus) and a stricture estimated to be of 13 mm diameter. This was subsequently dilated using a 20-mm-diameter balloon for 2 min followed by a 35-mm achalasia balloon for 3 min. The etiology remains undetermined in spite of a thorough history. The animal progressed satisfactorily, reaching 124 kg after 1 yr and has had no further signs. To the authors' knowledge, neither idiopathic esophageal stricture nor dilation using an achalasia balloon has been reported in Panthera spp.

Usefulness of sugammadex in a patient with Becker muscular dystrophy and dilated cardiomyopathy.

PubMed

Shimauchi, Tsukasa; Yamaura, Ken; Sugibe, Sayaka; Hoka, Sumio

2014-09-01

A 54-year-old patient with Becker muscular dystrophy and dilated cardiomyopathy underwent laparoscopic cholecystectomy under total intravenous anesthesia. Muscle relaxation was induced by rocuronium (0.4 mg/kg body weight) under train-of-four (TOF) ratio monitoring. The TOF ratio was 0 at intubation, and 0.2 at the end of surgery. Residual muscle relaxant activity was successfully reversed by sugammadex (2 mg/kg body weight) without any hemodynamic adverse effects (TOF ratio 1.0 at extubation). The clinical and hemodynamic findings suggest that sugammadex can be safely used in patients with Becker muscular dystrophy and dilated cardiomyopathy. Copyright © 2014. Published by Elsevier B.V.

Radionuclide esophageal transit: an evaluation of therapy in achalasia

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

McKinney, M.K.; Brady, C.E.; Weiland, F.L.

1983-09-01

We measured quantitative esophageal transit, expressed as percentage of esophageal retention, before and after pneumatic dilatation in two patients with achalasia. In the sitting position they ingested a 500 ml liquid meal containing 500 muCi technetium Tc 99m sulfur colloid. Radioactivity counts of the entire esophagus were plotted at five-minute intervals for 30 minutes. In five normal control subjects the esophagus essentially cleared in less than one minute. Both patients with achalasia had definite retention 30 minutes before dilatation and had quantitative improvement after dilatation. Radionuclide scintigraphic esophageal transit probably correlates better than other parameters with the physiologic degree ofmore » obstruction in achalasia.« less

Bile peritonitis associated with gastric dilation-volvulus in a dog.

PubMed

Hewitt, Saundra A; Brisson, Brigitte A; Holmberg, David L

2005-03-01

This report describes a case of septic peritonitis and gall bladder rupture in German shepherd dog that developed 7 d after surgical treatment for gastric dilation-volvulus. Histological examination confirmed gall bladder necrosis, secondary to an acute ischemic event. Postoperative acute necrotizing cholecystitis has not been a previously reported complication in dogs.

Addison's Disease and Dilated Cardiomyopathy: A Case Report and Review of the Literature

PubMed Central

Mozolevska, Viktoriya; Schwartz, Anna; Cheung, David; Shaikh, Bilal; Bhagirath, Kapil M.

2016-01-01

Addison's disease is often accompanied by a number of cardiovascular manifestations. We report the case of a 30-year-old man who presented with a new onset dilated cardiomyopathy due to Addison's disease. The clinical presentation, treatment, and outcomes of this rare hormone mediated cardiac disorder are reviewed. PMID:28003914

A Symmetry Approach to Time Dilation.

ERIC Educational Resources Information Center

Dunne, Peter

1995-01-01

Outlines an approach to introduce students to special relativity using a discussion of stopclocks and measurement of the transmission of light pulses to produce a natural derivation of the time dilation factor. Aims at providing a frame of reference from which they can be tempted to explore special relativity at a more sophisticated level. (JRH)

Addison's Disease and Dilated Cardiomyopathy: A Case Report and Review of the Literature.

PubMed

Mozolevska, Viktoriya; Schwartz, Anna; Cheung, David; Shaikh, Bilal; Bhagirath, Kapil M; Jassal, Davinder S

2016-01-01

Addison's disease is often accompanied by a number of cardiovascular manifestations. We report the case of a 30-year-old man who presented with a new onset dilated cardiomyopathy due to Addison's disease. The clinical presentation, treatment, and outcomes of this rare hormone mediated cardiac disorder are reviewed.

A Simple Derivation of Time Dilation and Length Contraction in Special Relativity

ERIC Educational Resources Information Center

Behroozi, Fred

2014-01-01

Undergraduate physics majors typically begin their study of modern physics with special relativity. It is here that physics students first encounter the counterintuitive concepts of time dilation and length contraction. Unfortunately, the derivations of these results are often cloaked in several layers of analysis that render them rather…

76 FR 36548 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-22

...] Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting AGENCY: Food and... of Committee: Circulatory System Devices Panel of the Medical Devices Advisory Committee. General... also comes with a sheath, introducer, loader, dilator, balloon (used to pre-dilate the native annulus...

77 FR 25183 - Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-27

...] Circulatory System Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting AGENCY: Food and... of Committee: Circulatory System Devices Panel of the Medical Devices Advisory Committee. General..., introducer, loader, dilator, balloon (used to pre-dilate the native annulus) and a crimper. FDA intends to...

Flicker Adaptation of Low-Level Cortical Visual Neurons Contributes to Temporal Dilation

ERIC Educational Resources Information Center

Ortega, Laura; Guzman-Martinez, Emmanuel; Grabowecky, Marcia; Suzuki, Satoru

2012-01-01

Several seconds of adaptation to a flickered stimulus causes a subsequent brief static stimulus to appear longer in duration. Nonsensory factors, such as increased arousal and attention, have been thought to mediate this flicker-based temporal-dilation aftereffect. In this study, we provide evidence that adaptation of low-level cortical visual…

The role of bulk viscosity on the decay of compressible, homogeneous, isotropic turbulence

NASA Astrophysics Data System (ADS)

Johnsen, Eric; Pan, Shaowu

2016-11-01

The practice of neglecting bulk viscosity in studies of compressible turbulence is widespread. While exact for monatomic gases and unlikely to strongly affect the dynamics of fluids whose bulk-to-shear viscosity ratio is small and/or of weakly compressible turbulence, this assumption is not justifiable for compressible, turbulent flows of gases whose bulk viscosity is orders of magnitude larger than their shear viscosities (e.g., CO2). To understand the mechanisms by which bulk viscosity and the associated phenomena affect compressible turbulence, we conduct DNS of freely decaying compressible, homogeneous, isotropic turbulence for ratios of bulk-to-shear viscosity ranging from 0-1000. Our simulations demonstrate that bulk viscosity increases the decay rate of turbulent kinetic energy; while enstrophy exhibits little sensitivity to bulk viscosity, dilatation is reduced by an order of magnitude within the two eddy turnover time. Via a Helmholtz decomposition of the flow, we determined that bulk viscosity damps the dilatational velocity and reduces dilatational-solenoidal exchanges, as well as pressure-dilatation coupling. In short, bulk viscosity renders compressible turbulence incompressible by reducing energy transfer between translational and internal modes.

Review of the use of intralesional steroid injections in the management of ileocolonic Crohn's strictures

PubMed Central

Bevan, Roisin; Rees, Colin J; Rutter, Matthew D; Macafee, David A L

2013-01-01

Most patients with Crohn's disease present with either terminal ileal or colonic disease, with 70% requiring surgery by 10 years after diagnosis. Recurrent stricturing at the anastomotic site is common, often symptomatic and can require re-operation with its inherent risks. Balloon dilation has been shown to provide good symptom relief from such strictures. However, repeat dilations may be required, and further surgical intervention to an anastomotic stricture is needed in up to 30% of cases. Injection of corticosteroids has been suggested as an adjunct to dilation in order to improve outcomes. This paper reviews the current literature on the use of intralesional steroid injections following endoscopic balloon dilation of anastomotic and de novo Crohn's strictures. There have been only two randomised placebo controlled trials and five small non-controlled or retrospective studies. Study numbers vary from 10 to 29 patients. The two randomised trials conflict in their conclusions and numbers are small in these studies. Currently therefore, no firm support can be given to the routine use of intralesional steroid injections. PMID:28839732

Texture classification using non-Euclidean Minkowski dilation

NASA Astrophysics Data System (ADS)

Florindo, Joao B.; Bruno, Odemir M.

2018-03-01

This study presents a new method to extract meaningful descriptors of gray-scale texture images using Minkowski morphological dilation based on the Lp metric. The proposed approach is motivated by the success previously achieved by Bouligand-Minkowski fractal descriptors on texture classification. In essence, such descriptors are directly derived from the morphological dilation of a three-dimensional representation of the gray-level pixels using the classical Euclidean metric. In this way, we generalize the dilation for different values of p in the Lp metric (Euclidean is a particular case when p = 2) and obtain the descriptors from the cumulated distribution of the distance transform computed over the texture image. The proposed method is compared to other state-of-the-art approaches (such as local binary patterns and textons for example) in the classification of two benchmark data sets (UIUC and Outex). The proposed descriptors outperformed all the other approaches in terms of rate of images correctly classified. The interesting results suggest the potential of these descriptors in this type of task, with a wide range of possible applications to real-world problems.

Pupillary Reactivity to Emotional Stimuli in Children of Depressed and Anxious Mothers

PubMed Central

Burkhouse, Katie L.; Siegle, Greg J.; Gibb, Brandon E.

2014-01-01

Background The primary aim of the current study was to examine differences in physiological reactivity (measured via pupillometry) to emotional stimuli between children of depressed vs. nondepressed mothers. A second goal was to examine differences in pupil dilation to emotional stimuli between children of anxious vs. nonanxious mothers. Method Participants included 117 mother-child pairs drawn from the community. Children were between the ages of 8 and 14. Pupil dilation was assessed using an eye-tracker while participants viewed angry, happy, or sad faces. Results Children of mothers with a history of major depression (MDD) exhibited increased pupil dilation to sad, but not happy or angry, faces compared to children of nondepressed mothers. Second, we found that children of anxious mothers exhibited increased pupil dilation to angry, but not happy or sad, faces compared to youth of nonanxious mothers. Conclusions The current findings add to the growing body of research suggesting that differences in physiological reactivity to depression- and anxiety-relevant cues may represent an important mechanism in the intergenerational transmission of MDD and anxiety. PMID:24635760

Retrograde non trans-septal balloon mitral valvotomy in mitral stenosis with interrupted inferior vena cava, left superior vena cava, and hugely dilated coronary sinus.

PubMed

Nath, Ranjit Kumar; Soni, Dheeraj Kumar

2015-12-01

A 22-year-old woman with severe mitral stenosis was referred to us for further evaluation and management. She was found to have severe mitral stenosis, severe tricuspid regurgitation with dilated right atrium and right ventricle with persistent left superior vena cava and hugely dilated coronary sinus. Valve was suitable for balloon mitral valvotomy. Cardiac catheterization showed interrupted inferior vena cava with azygos continuation to right atrium and large left superior vena cava draining to coronary sinus which was very much dilated. Right trans-jugular approach was tried for balloon mitral valvotomy, but was unsuccessful due to a very large right atrium and coronary sinus. Retrograde non trans-septal approach was used and balloon valvotomy was done successfully using a 24 mm × 40 mm TYSHAK balloon without any major complication. Reduction in the transmitral pressure gradient on cardiac catheterization data and transthoracic echocardiography confirmed successful procedure. Balloon mitral valvotomy can be done successfully in patients with the above unusual cardiac anatomy with no major procedural complications. © 2015 Wiley Periodicals, Inc.

Interfacial dilatational deformation accelerates particle formation in monoclonal antibody solutions.

PubMed

Lin, Gigi L; Pathak, Jai A; Kim, Dong Hyun; Carlson, Marcia; Riguero, Valeria; Kim, Yoen Joo; Buff, Jean S; Fuller, Gerald G

2016-04-14

Protein molecules are amphiphilic moieties that spontaneously adsorb at the air/solution (A/S) interface to lower the surface energy. Previous studies have shown that hydrodynamic disruptions to these A/S interfaces can result in the formation of protein aggregates that are of concern to the pharmaceutical industry. Interfacial hydrodynamic stresses encountered by protein therapeutic solutions under typical manufacturing, filling, and shipping conditions will impact protein stability, prompting a need to characterize the contribution of basic fluid kinematics to monoclonal antibody (mAb) destabilization. We demonstrate that dilatational surface deformations are more important to antibody stability when compared to constant-area shear of the A/S interface. We have constructed a dilatational interfacial rheometer that utilizes simultaneous pressure and bubble shape measurements to study the mechanical stability of mAbs under interfacial aging. It has a distinct advantage over methods utilizing the Young-Laplace equation, which incorrectly describes viscoelastic interfaces. We provide visual evidence of particle ejection from dilatated A/S interfaces and spectroscopic data of ejected mAb particles. These rheological studies frame a molecular understanding of the protein-protein interactions at the complex-fluid interface.

[Interventional catheter treatment of bypass graft stenosis: comparison of intracoronary stent implantation and balloon angioplasty].

PubMed

Heidland, U E; Heintzen, M P; Schoppmann, D; Michel, C J; Strauer, B E

2000-02-25

Balloon angioplasty of a stenosed bypass graft has a much higher risk of recurrent stenosis than dilatation of a stenosed native coronary artery. Intracoronary stent implantation has established itself as the better treatment of native coronary artery stenosis than conventional balloon angioplasty. However, there is still uncertainty whether intracoronary stent implantation in stenosed bypass vessels gives better long-term results than conventional balloon angioplasty. Results were retrospectively analyzed of unrandomized 224 primarily successful interventions--122 balloon dilatations and 102 stent implantations--performed between January 1996 and June 1998 on stenosed coronary bypass grafts, re-examined by coronary angiography an average of 6 months later. All but 11 patients were on combined aspirin and ticlopidine antiplatelet aggregation treatment. There was a significantly lower 6-month restenosis rate (30.4%) after stent implantation than after balloon dilatation (51.6%). The re-intervention rate was also significantly lower after stent implantation. These data suggest that stent implantation of stenosed coronary bypass grafts under cover of platelet-aggregation inhibition with aspirin and ticlopidine provides a lower restenosis and thus higher revascularization rate than conventional balloon dilatation.

Dilatancy and shear thickening of particle suspensions

NASA Astrophysics Data System (ADS)

Bonn, Daniel

2013-03-01

Shear thickening is a fascinating subject, as 99.9% of complex fluids are thinning; thickening systems thus are the ``exception to the rule'' that needs to be understood. Moreover, such tunable systems show very promising applications, e.g. to block large underground pores in oil recovery to maintain a constant oil flow by plugging water filled pores (an approach used in oil recovery by e.g. Shell), or to manufacture bulletproof vests that are comfortable to wear, but stop bullets nonetheless. We study the rheology of non-Brownian particle suspensions (notably, cornstarch) that exhibit shear thickening. Using magnetic resonance imaging (MRI), the local properties of the flow are obtained by the determination of local velocity profiles and concentrations in a Couette cell. We also perform macroscopic rheology experiments in different geometries. The results suggest that the shear thickening is a consequence of dilatancy: the system under flow attempts to dilate but instead undergoes a jamming transition, because it is confined. This proposition is confirmed by an independent measurement of the dilation of the suspension as a function of the shear rate.

Balloon dilation and intralesional steroid for benign rectal stricture management in a cat.

PubMed

Chavkin, Jessica A; Spector, Donna J; Stanley, Skye W

2010-08-01

A 4-year-old castrated male domestic shorthair presented for 1 week of constipation and tenesmus. A rectal stricture had been diagnosed 8 months prior at the time of adoption and the cat had been successfully managed with stool softeners until presentation. A complete diagnostic work-up failed to reveal an underlying etiology for the stricture and colonoscopy was performed. Endoscopic biopsies of the stricture revealed benign non-specific inflammatory changes. Balloon dilation of the rectal stricture was performed during the initial colonoscopy and 3 and 9 days later. Triamcinolone acetonide was injected into the stricture site with endoscopic guidance during the third dilation procedure. The patient has been monitored for over 27 months; follow-up indicates no signs of tenesmus and repeated rectal examinations reveal no stricture recurrence. This case report demonstrates that endoscopic balloon dilation with intralesional steroid injection represented a minimally invasive and effective option for the treatment of a benign rectal stricture in this cat, and deserves further prospective investigation. Copyright 2010 ISFM and AAFP. Published by Elsevier Ltd. All rights reserved.

Periodic oscillation of intracranial pressure in ventricular dilation: a preliminary report.

PubMed

Kuchiwaki, H; Misu, N; Kageyama, N; Ishiguri, H; Takada, S

1987-12-01

Artificial pressure waves (PWs) were generated by manual inflation of a balloon in the trigonum of the lateral ventricle in seven adult mongrel dogs with normal cerebrospinal fluid (CSF) circulation. In 14 of 16 series of continuous appearances of artificial PWs, local shifts of the brain were successfully monitored using small strain-gauge sensors at the periventricular structures in these animals. Of the 14 series, 13 showed displacements of the periventricular structures, suggesting ventricular dilation. These results did not always correlate with macroscopic findings. They are thought to be due largely to periventricular oedemas and, in part, non-uniform dilations of the ventricles during PWs. We conclude that a water hammer formed by reflection of an increased pulse pressure of PWs at the site of CSF absorption causes a shift of CSF from the ventricle to the periventricular structures through the wall of the ventricle. This phenomenon appears amplified in patients with impaired CSF absorption. Thus, PWs have a pathological role in the progress of ventricular dilation in patients with normal pressure hydrocephalus.

Direct simulation of compressible turbulence in a shear flow

NASA Technical Reports Server (NTRS)

Sarkar, S.; Erlebacher, G.; Hussaini, M. Y.

1991-01-01

Compressibility effects on the turbulence in homogeneous shear flow are investigated. The growth of the turbulent kinetic energy was found to decrease with increasing Mach number: a phenomenon which is similar to the reduction of turbulent velocity intensities observed in experiments on supersonic free shear layers. An examination of the turbulent energy budget shows that both the compressible dissipation and the pressure-dilatation contribute to the decrease in the growth of kinetic energy. The pressure-dilatation is predominantly negative in homogeneous shear flow, in contrast to its predominantly positive behavior in isotropic turbulence. The different signs of the pressure-dilatation are explained by theoretical consideration of the equations for the pressure variance and density variance. Previously, the following results were obtained for isotropic turbulence: (1) the normalized compressible dissipation is of O(M(sub t)(exp 2)); and (2) there is approximate equipartition between the kinetic and potential energies associated with the fluctuating compressible mode. Both of these results were substantiated in the case of homogeneous shear. The dilatation field is significantly more skewed and intermittent than the vorticity field. Strong compressions seem to be more likely than strong expansions.

The influence of compressibility on nonlinear spectral energy transfer - Part 1: Fundamental mechanisms

NASA Astrophysics Data System (ADS)

Praturi, Divya Sri; Girimaji, Sharath

2017-11-01

Nonlinear spectral energy transfer by triadic interactions is one of the foundational processes in fluid turbulence. Much of our current knowledge of this process is contingent upon pressure being a Lagrange multiplier with the only function of re-orienting the velocity wave vector. In this study, we examine how the nonlinear spectral transfer is affected in compressible turbulence when pressure is a true thermodynamic variable with a wave character. We perform direct numerical simulations of multi-mode evolution at different turbulent Mach numbers of Mt = 0.03 , 0.6 . Simulations are performed with initial modes that are fully solenoidal, fully dilatational and mixed solenoidal-dilatational. It is shown that solenoidal-solenoidal interactions behave in canonical manner at all Mach numbers. However, dilatational and mixed mode interactions are profoundly different. This is due to the fact that wave-pressure leads to kinetic-internal energy exchange via the pressure-dilatation mechanism. An important consequence of this exchange is that the triple correlation term, responsible for spectral transfer, experiences non-monotonic behavior resulting in inefficient energy transfer to other modes.

Ross procedure for ascending aortic replacement.

PubMed

Elkins, R C; Lane, M M; McCue, C

1999-06-01

Patients with aortic valve disease and aneurysm or dilatation of the ascending aorta require both aortic valve replacement and treatment of their ascending aortic disease. In children and young adults, the Ross operation is preferred when the aortic valve requires replacement, but the efficacy of extending this operation to include replacement of the ascending aorta or reduction of the dilated aorta has not been tested. We reviewed the medical records of 18 (5.9%) patients with aortic valve disease and an ascending aortic aneurysm and 26 (8.5%) patients with dilation of the ascending aorta, subgroups of 307 patients who had a Ross operation between August 1986 and February 1998. We examined operative and midterm results, including recent echocardiographic assessment of autograft valve function and ability of the autograft root and ascending aortic repair or replacement to maintain normal structural integrity. There was one operative death (2%) related to a perioperative stroke. Forty-two of 43 survivors have normal autograft valve function, with trace to mild autograft valve insufficiency, and one patient has moderate insufficiency at the most recent echocardiographic evaluation. None of the patients has dilatation of the autograft root or of the replaced or reduced ascending aorta. Early results with extension of the Ross operation to include replacement of an ascending aortic aneurysm or vertical aortoplasty for reduction of a dilated ascending aorta are excellent, with autograft valve function equal to that seen in similar patients without ascending aortic disease.

Evolution of fault zones in carbonates with mechanical stratigraphy - Insights from scale models using layered cohesive powder

NASA Astrophysics Data System (ADS)

van Gent, Heijn W.; Holland, Marc; Urai, Janos L.; Loosveld, Ramon

2010-09-01

We present analogue models of the formation of dilatant normal faults and fractures in carbonate fault zones, using cohesive hemihydrate powder (CaSO 4·½H 2O). The evolution of these dilatant fault zones involves a range of processes such as fragmentation, gravity-driven breccia transport and the formation of dilatant jogs. To allow scaling to natural prototypes, extensive material characterisation was done. This showed that tensile strength and cohesion depend on the state of compaction, whereas the friction angle remains approximately constant. In our models, tensile strength of the hemihydrate increases with depth from 9 to 50 Pa, while cohesion increases from 40 to 250 Pa. We studied homogeneous and layered material sequences, using sand as a relatively weak layer and hemihydrate/graphite mixtures as a slightly stronger layer. Deformation was analyzed by time-lapse photography and Particle Image Velocimetry (PIV) to calculate the evolution of the displacement field. With PIV the initial, predominantly elastic deformation and progressive localization of deformation are observed in detail. We observed near-vertical opening-mode fractures near the surface. With increasing depth, dilational shear faults were dominant, with releasing jogs forming at fault-dip variations. A transition to non-dilatant shear faults was observed near the bottom of the model. In models with mechanical stratigraphy, fault zones are more complex. The inferred stress states and strengths in different parts of the model agree with the observed transitions in the mode of deformation.

Management of complex glottic stenosis in children with recurrent respiratory papillomatosis.

PubMed

Siegel, Bianca; Smith, Lee P

2013-10-01

To describe our management of complex glottic stenosis in tracheotomy dependent children with severe recurrent respiratory papillomatosis. Retrospective chart review at a tertiary care children's hospital. Three children with complex glottic stenosis secondary to severe recurrent respiratory papillomatosis were treated at our institution since 2011. Two patients had complete stenosis, and the third had near-complete stenosis. Two patients were managed using balloon dilation alone, and the third also underwent laryngotracheal reconstruction with posterior costal cartilage grafting. Two patients have been successfully decannulated and the third has been tolerating continuous tracheotomy capping for greater than twelve months. All three patients underwent aggressive debridement of papillomatosis and balloon dilation every 4-6 weeks until their burden of disease was controlled. In two patients, the glottic airway was patent, and the third continued to have complete restenosis between procedures and required laryngotracheoplasty with multiple post-operative dilation procedures to establish an adequate glottic airway. Severe laryngeal stenosis is a well-described complication of recurrent respiratory papillomatosis, but its management is not well-defined. Aggressive management of papillomatosis with frequent debridement is critical in successfully managing laryngeal stenosis. Balloon dilation alone may be surprisingly effective in these patients, and laryngotracheoplasty can be used as an adjunct procedure in those patients who fail balloon dilation. Given the quality of life issues and concerns regarding distal spread of disease with tracheotomies in these patients, we feel that aggressive management and early decannulation is in the patient's best interest. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Dilatant shear band formation and diagenesis in calcareous, arkosic sandstones, Vienna Basin (Austria)

PubMed Central

Lommatzsch, Marco; Exner, Ulrike; Gier, Susanne; Grasemann, Bernhard

2015-01-01

The present study examines deformation bands in calcareous arkosic sands. The investigated units can be considered as an equivalent to the Matzen field in the Vienna Basin (Austria), which is one of the most productive oil reservoirs in central Europe. The outcrop exposes carbonate-free and carbonatic sediments of Badenian age separated by a normal fault. Carbonatic sediments in the hanging wall of the normal fault develop dilation bands with minor shear displacements (< 2 mm), whereas carbonate-free sediments in the footwall develop cataclastic shear bands with up to 70 cm displacement. The cataclastic shear bands show a permeability reduction up to 3 orders of magnitude and strong baffling effects in the vadose zone. Carbonatic dilation bands show a permeability reduction of 1-2 orders of magnitude and no baffling structures. We distinguished two types of deformation bands in the carbonatic units, which differ in deformation mechanisms, distribution and composition. Full-cemented bands form as dilation bands with an intense syn-kinematic calcite cementation, whereas the younger loose-cemented bands are dilatant shear bands cemented by patchy calcite and clay minerals. All analyzed bands are characterized by a porosity and permeability reduction caused by grain fracturing and cementation. The changed petrophysical properties and especially the porosity evolution are closely related to diagenetic processes driven by varying pore fluids in different diagenetic environments. The deformation band evolution and sealing capacity is controlled by the initial host rock composition. PMID:26300577

An Upgrade on the Rabbit Model of Anthracycline-Induced Cardiomyopathy: Shorter Protocol, Reduced Mortality, and Higher Incidence of Overt Dilated Cardiomyopathy

PubMed Central

Talavera, Jesús; Fernández-Del-Palacio, María Josefa; García-Nicolás, Obdulio; Seva, Juan; Brooks, Gavin; Moraleda, Jose M.

2015-01-01

Current protocols of anthracycline-induced cardiomyopathy in rabbits present with high premature mortality and nephrotoxicity, thus rendering them unsuitable for studies requiring long-term functional evaluation of myocardial function (e.g., stem cell therapy). We compared two previously described protocols to an in-house developed protocol in three groups: Group DOX2 received doxorubicin 2 mg/kg/week (8 weeks); Group DAU3 received daunorubicin 3 mg/kg/week (10 weeks); and Group DAU4 received daunorubicin 4 mg/kg/week (6 weeks). A cohort of rabbits received saline (control). Results of blood tests, cardiac troponin I, echocardiography, and histopathology were analysed. Whilst DOX2 and DAU3 rabbits showed high premature mortality (50% and 33%, resp.), DAU4 rabbits showed 7.6% premature mortality. None of DOX2 rabbits developed overt dilated cardiomyopathy; 66% of DAU3 rabbits developed overt dilated cardiomyopathy and quickly progressed to severe congestive heart failure. Interestingly, 92% of DAU4 rabbits showed overt dilated cardiomyopathy and 67% developed congestive heart failure exhibiting stable disease. DOX2 and DAU3 rabbits showed alterations of renal function, with DAU3 also exhibiting hepatic function compromise. Thus, a shortened protocol of anthracycline-induced cardiomyopathy as in DAU4 group results in high incidence of overt dilated cardiomyopathy, which insidiously progressed to congestive heart failure, associated to reduced systemic compromise and very low premature mortality. PMID:26788502

Exercise training-enhanced, endothelium-dependent dilation mediated by altered regulation of BKCa channels in collateral-dependent porcine coronary arterioles

PubMed Central

Xie, Wei; Parker, Janet L.; Heaps, Cristine L.

2012-01-01

Objective Test the hypothesis that exercise training increases the contribution of large-conductance, Ca2+-dependent K+ (BKCa) channels to endothelium-mediated dilation in coronary arterioles from collateral-dependent myocardial regions of chronically occluded pig hearts and may function downstream of H2O2. Methods An ameroid constrictor was placed around the proximal left circumflex coronary artery to induce gradual occlusion in Yucatan miniature swine. Eight weeks postoperatively, pigs were randomly assigned to sedentary or exercise training (treadmill; 14 wk) regimens. Results Exercise training significantly enhanced bradykinin-mediated dilation in collateral-dependent arterioles (~125 μm diameter) compared with sedentary pigs. The BKCa-channel blocker, iberiotoxin alone or in combination with the H2O2 scavenger, polyethylene glycol catalase, reversed exercise training-enhanced dilation in collateral-dependent arterioles. Iberiotoxin-sensitive whole-cell K+ currents (i.e., BKCa-channel currents) were not different between smooth muscle cells of nonoccluded and collateral-dependent arterioles of sedentary and exercise trained groups. Conclusions These data provide evidence that BKCa-channel activity contributes to exercise training-enhanced endothelium-dependent dilation in collateral-dependent coronary arterioles despite no change in smooth muscle BKCa-channel current. Taken together, our findings suggest that a component of the bradykinin signaling pathway, which stimulates BKCa channels, is enhanced by exercise training in collateral-dependent arterioles and suggest a potential role for H2O2 as the mediator. PMID:23002811

Closed transventricular dilation of discrete subvalvular aortic stenosis in dogs.

PubMed

Linn, K; Orton, E C

1992-01-01

Discrete subvalvular aortic stenosis with peak systolic pressure gradients of more than 60 mm Hg was treated by closed transventricular dilation in six young dogs. Peak systolic pressure gradients were measured by direct catheterization before surgery, immediately after dilation, and 3 months after surgery. Maximum instantaneous pressure gradients were measured by continuous wave Doppler echocardiography before surgery and 6 weeks to 9 months after surgery. All dogs survived the procedure, and two dogs were clinically normal after 9 and 14 months. Two dogs died at week 6 and month 7. One dog was receiving medication for pulmonary edema 15 months after surgery. One dog underwent open resection of the subvalvular ring at month 3, and was clinically normal 6 months after the second procedure. Complications included intraoperative ventricular fibrillation in one dog, and mild postoperative aortic insufficiency in one dog. Closed transventricular dilation resulted in an immediate 83% decrease in the peak systolic pressure gradient from a preoperative mean of 97 +/- 22 mm Hg to a mean of 14 +/- 15 mm Hg. However, systolic pressure gradients measured by direct catheterization at month 3 (77 +/- 26 mm Hg), and by Doppler echocardiography at week 6 to month 9 (85 +/- 32 mm Hg) were not significantly different from preoperative values, which suggested recurrence of the aortic stenosis. Closed transventricular dilation should not be considered a definitive treatment for discrete subvalvular aortic stenosis in dogs, but may be useful in young dogs with critical aortic stenosis as a bridge to more definitive surgery.

Sex-specific effects of cardiovascular risk factors on endothelium-dependent dilation and endothelin activity in middle-aged women and men.

PubMed

Brar, Vijaywant; Gill, Sartaj; Cardillo, Carmine; Tesauro, Manfredi; Panza, Julio A; Campia, Umberto

2015-01-01

Healthy middle-aged postmenopausal women have higher endothelium-dependent dilation and lower vasoconstrictor activity of endothelin-1 than men. Whether these sex-specific differences extend to patients with cardiovascular risk factors has not been investigated. The current study aimed to determine whether, in patients with cardiovascular risk factors, sex-specific differences exist in endothelium-dependent dilation and endothelin-1 activity. Forearm blood flow responses were measured by strain-gauge plethysmography during the intra-arterial infusion of acetylcholine, sodium nitroprusside, and the selective endothelin type A receptor blocker BQ-123 in 50 women and 64 men with cardiovascular risk factors. Acetylcholine and sodium nitroprusside induced a significant vasodilation in women and men alike (p < 0.01 for both). Also BQ-123 caused a significant vasodilation (p < 0.001) in both groups. The vasodilator response to acetylcholine was greater in women compared to men; however there were no differences in the response to sodium nitroprusside and BQ-123 (p = NS for both) between the two sex groups. Middle-aged women with cardiovascular risk factors have significantly higher endothelium-dependent dilation than middle-aged men; however, vascular endothelin 1 activity is similar in the two groups. These findings suggest that the presence of cardiovascular risk factors is associated with sex-specific effects on endothelium-dependent dilation but not on endothelin 1 activity. Further study is needed to confirm our findings and to characterize the mechanisms underlying this sex-specific regulation of endothelial function.

Shaker-related voltage-gated K+ channel expression and vasomotor function in human coronary resistance arteries.

PubMed

Nishijima, Yoshinori; Korishettar, Ankush; Chabowski, Dawid S; Cao, Sheng; Zheng, Xiaodong; Gutterman, David D; Zhang, David X

2018-01-01

K V channels are important regulators of vascular tone, but the identity of specific K V channels involved and their regulation in disease remain less well understood. We determined the expression of K V 1 channel subunits and their role in cAMP-mediated dilation in coronary resistance arteries from subjects with and without CAD. HCAs from patients with and without CAD were assessed for mRNA and protein expression of K V 1 channel subunits with molecular techniques and for vasodilator response with isolated arterial myography. Assays of mRNA transcripts, membrane protein expression, and vascular cell-specific localization revealed abundant expression of K V 1.5 in vascular smooth muscle cells of non-CAD HCAs. Isoproterenol and forskolin, two distinct cAMP-mediated vasodilators, induced potent dilation of non-CAD arterioles, which was inhibited by both the general K V blocker 4-AP and the selective K V 1.5 blocker DPO-1. The cAMP-mediated dilation was reduced in CAD and was accompanied by a loss of or reduced contribution of 4-AP-sensitive K V channels. K V 1.5, as a major 4-AP-sensitive K V 1 channel expressed in coronary VSMCs, mediates cAMP-mediated dilation in non-CAD arterioles. The cAMP-mediated dilation is reduced in CAD coronary arterioles, which is associated with impaired 4-AP-sensitive K V channel function. © 2017 John Wiley & Sons Ltd.

A left ventricular epicardial to right ventricular endocardial dominant frequency gradient exists in human ventricular fibrillation.

PubMed

Torres, Jose Luis; Shah, Bindi K; Greenberg, Richard M; Deger, Florin Titus; Gerstenfeld, Edward P

2010-10-01

We hypothesized that in patients with left ventricular dysfunction undergoing implant of a biventricular ICD, the local dominant frequency during early induced ventricular fibrillation would be higher at an epicardial left ventricular position compared to an endocardial right ventricular position. Patients undergoing implant of a biventricular ICD were studied. During ventricular fibrillation induction, bipolar electrograms were recorded from leads at an epicardial left ventricular position and an endocardial right ventricular position. Overlapping 2-s fast Fourier transforms were obtained for 6 s of ventricular fibrillation. The dominant frequency and organizational index were compared. Thirty-four patients (20 men, age 64 ± 11 years) underwent 57 inductions of ventricular fibrillation. Eighteen patients had non-ischemic dilated cardiomyopathy and 16 had ischemic dilated cardiomyopathy. The dominant frequency was higher at a lateral epicardial left ventricular position than an apical endocardial right ventricular position in 18 patients with non-ischemic dilated cardiomyopathy (LV epicardial 5.34 ± 0.37 Hz, RV endocardial 5.09 ± 0.41 Hz, p < 0.001), but not in 16 patients with ischemic dilated cardiomyopathy (LV epicardial 4.99 ± 0.57 Hz, RV epicardial 4.87 ± 0.65 Hz, p = 0.094). In patients with non-ischemic dilated cardiomyopathy, there is a dominant frequency gradient during early ventricular fibrillation induced at ICD testing from the lateral left ventricular epicardium to the apical right ventricular endocardium.

[The Collis-Nissen operation in the treatment of reflux due to esophageal stenoses associated with brachioesophagus].

PubMed

Gerzić, Z; Rakić, S

1990-01-01

Eight patients with esophageal reflux strictures and brachioesophagus were treated by endoscopic dilatation and the Collis-Nissen procedure between 1986 and 1990 at the Institute of Digestive Diseases, Belgrade University Clinical Center. Dilatation of the esophageal stricture was performed by the Eder-Puestow system. All strictures were dilated preoperatively to in average 45 Fr without any complications recorded. The average duration of the Collis-Nissen operation was 3.5 hours and it was hastened by the usage of GIA surgical stapler for construction of the Collis gastroplasty tube. Postoperative course was uneventrful in all eight patients and by dismissal all of them had satisfactory relief of dysphagia and barium esophagogram. Postoperative hospital stay averaged 13.0 days. Satisfactory symptomatic control of gastroesophageal reflux (no symptoms, no treatment) was achieved in 5 patients at a long-term follow-up. Two patients required periodic dilatations and antireflux therapy during the first postoperative year to achieve resolution of the dysphagia and no need for medical therapy. One patient had objective failure of reflux control and progression of stricture formation requiring reoperation. This patient underwent esophagectomy and esophagocoloplasty with a subsequent good result. The combined Collis gastroplasty-Nissen funduplication has become the operation of choice in patients with dilatable reflux stricture and esophageal shortening and a reasonable alternative to a formidable resectional procedures. This report evaluates the first experiences with a Collis-Nissen procedure in our country.

Task-evoked pupillometry provides a window into the development of short-term memory capacity.

PubMed

Johnson, Elizabeth L; Miller Singley, Alison T; Peckham, Andrew D; Johnson, Sheri L; Bunge, Silvia A

2014-01-01

The capacity to keep multiple items in short-term memory (STM) improves over childhood and provides the foundation for the development of multiple cognitive abilities. The goal of this study was to measure the extent to which age differences in STM capacity are related to differences in task engagement during encoding. Children (n = 69, mean age = 10.6 years) and adults (n = 54, mean age = 27.5 years) performed two STM tasks: the forward digit span test from the Wechsler Intelligence Scale for Children (WISC) and a novel eyetracking digit span task designed to overload STM capacity. Building on prior research showing that task-evoked pupil dilation can be used as a real-time index of task engagement, we measured changes in pupil dilation while participants encoded long sequences of digits for subsequent recall. As expected, adults outperformed children on both STM tasks. We found similar patterns of pupil dilation while children and adults listened to the first six digits on our STM overload task, after which the adults' pupils continued to dilate and the children's began to constrict, suggesting that the children had reached their cognitive limits and that they had begun to disengage from the task. Indeed, the point at which pupil dilation peaked at encoding was a significant predictor of WISC forward span, and this relationship held even after partialing out recall performance on the STM overload task. These findings indicate that sustained task engagement at encoding is an important component of the development of STM.

Ultrasound Guidance for Renal Tract Access and Dilation Reduces Radiation Exposure during Percutaneous Nephrolithotomy

PubMed Central

2016-01-01

Purposes. To present our series of 38 prone percutaneous nephrolithotomy procedures performed with renal access and tract dilation purely under ultrasound guidance and describe the benefits and challenges accompanying this approach. Methods. Thirty-eight consecutive patients presenting for percutaneous nephrolithotomy for renal stone removal were included in this prospective cohort study. Ultrasonographic imaging in the prone position was used to obtain percutaneous renal access and guide tract dilation. Fluoroscopic screening was used only for nephrostomy tube placement. Preoperative, intraoperative, and postoperative procedural and patient data were collected for analysis. Results. Mean age of patients was 52.7 ± 17.2 years. Forty-five percent of patients were male with mean BMI of 26.1 ± 7.3 and mean stone size of 27.2 ± 17.6 millimeters. Renal puncture was performed successfully with ultrasonographic guidance in all cases with mean puncture time of 135.4 ± 132.5 seconds. Mean dilation time was 11.5 ± 3.8 min and mean stone fragmentation time was 37.5 ± 29.0 min. Mean total operative time was 129.3 ± 41.1. No patients experienced any significant immediate postoperative complication. All patients were rendered stone-free and no additional secondary procedures were required. Conclusions. Ultrasound guidance for renal access and tract dilation in prone percutaneous nephrolithotomy is a feasible and effective technique. It can be performed safely with significantly reduced fluoroscopic radiation exposure to the patient, surgeon, and intraoperative personnel. PMID:27042176

Pulmonary arterial pressure and right ventricular dilatation independently determine tricuspid valve insufficiency severity in pre-capillary pulmonary hypertension.

PubMed

De Meester, Pieter; Van De Bruaene, Alexander; Delcroix, Marion; Belmans, Ann; Herijgers, Paul; Voigt, Jens-Uwe; Budts, Werner

2012-11-01

Elevated pulmonary artery systolic pressure (PASP) causes functional tricuspid valve insufficiency (TI). However, the differential contribution of pressure load and right ventricular (RV) dilatation is not well established. The study aim was to evaluate both variables in relation to TI. A cross-sectional study was performed of consecutive transthoracic echocardiographic studies of patients with pre-capillary pulmonary hypertension (PH). Both, demographic data and echocardiographic RV parameters were reviewed. TI was graded semi-quantitatively with color Doppler flow imaging. Trend analyses for TI severity (TI grade 0/4, 1/4, 2/4, 3/4, or 4/4) were performed. A proportional odds logistic regression analysis was carried out to identify independent predictors of TI severity. Eighty-one patients (56 females, 25 males; mean age 60 +/- 15 years) with pre-capillary PH were evaluated. Patients with more severe TI had a significantly lower body mass index, a lower mean systemic blood pressure, a shorter pulmonary acceleration time, a higher tricuspid regurgitant gradient, and a more dilated right ventricle. From the echocardiographic parameters, RV dilatation (p = 0.0143) and the tricuspid regurgitant gradient (p = 0.0026) were independently related to the degree of TI. In patients with pre-capillary PH, PASP and RV dilatation were both related to the increasing severity of TI. When focusing on TI to improve the prognosis of patients with pre-capillary PH, both PASP and RV dimensions should be taken into consideration.

Usefulness of Ultrasonography and Cortical Transit Time to Differentiate Nonobstructive From Obstructive Dilatation in the Management of Prenatally Detected Pelvic Ureteric Junction Like Obstruction.

PubMed

Sharma, Gyanendra; Sharma, Anshu

2017-12-01

To differentiate a nonobstructive dilatation from an obstructive dilatation in prenatally detected presumed pelvi-ureteric junction obstruction so that intervention can be planned before irreversible damage can occur to the renal unit. From January 2012 to December 2016, all patients with prenatally detected or asymptomatic incidentally detected presumed pelvi-ureteric junction obstruction were evaluated by ultrasonography and renogram. The anteroposterior diameter of the renal pelvis was measured in supine and prone position. Presence of calyceal dilatation in prone position was noted. They were categorized into obstructed, nonobstructed, and equivocal groups based on sonography findings. The differential renal function and the cortical transit time (CTT) was calculated and compared with the sonography groups. Of the 98 patients, 72 were in the obstructed, 18 were in the nonobstructed, and 8 were in the equivocal category. All except 1 in the nonobstructed category had a function of >40% with CTT of <3 minutes. Seventy patients in the obstructed category had a CTT of >3 minutes, whereas 61 had function <40% on initial evaluation. Eleven patients in the obstructed category with an initial function of >40% had CTT of >3 minutes. All of them showed increasing hydronephrosis and deterioration of function during follow-up, necessitating pyeloplasty. All patients in the equivocal group had function >40% and CTT <3 minutes. Ultrasonography along with CTT can help to differentiate nonobstructive from obstructive dilatation. Copyright © 2017 Elsevier Inc. All rights reserved.

Computer-Based Image Analysis for Plus Disease Diagnosis in Retinopathy of Prematurity

PubMed Central

Wittenberg, Leah A.; Jonsson, Nina J.; Chan, RV Paul; Chiang, Michael F.

2014-01-01

Presence of plus disease in retinopathy of prematurity (ROP) is an important criterion for identifying treatment-requiring ROP. Plus disease is defined by a standard published photograph selected over 20 years ago by expert consensus. However, diagnosis of plus disease has been shown to be subjective and qualitative. Computer-based image analysis, using quantitative methods, has potential to improve the objectivity of plus disease diagnosis. The objective was to review the published literature involving computer-based image analysis for ROP diagnosis. The PubMed and Cochrane library databases were searched for the keywords “retinopathy of prematurity” AND “image analysis” AND/OR “plus disease.” Reference lists of retrieved articles were searched to identify additional relevant studies. All relevant English-language studies were reviewed. There are four main computer-based systems, ROPtool (AU ROC curve, plus tortuosity 0.95, plus dilation 0.87), RISA (AU ROC curve, arteriolar TI 0.71, venular diameter 0.82), Vessel Map (AU ROC curve, arteriolar dilation 0.75, venular dilation 0.96), and CAIAR (AU ROC curve, arteriole tortuosity 0.92, venular dilation 0.91), attempting to objectively analyze vessel tortuosity and dilation in plus disease in ROP. Some of them show promise for identification of plus disease using quantitative methods. This has potential to improve the diagnosis of plus disease, and may contribute to the management of ROP using both traditional binocular indirect ophthalmoscopy and image-based telemedicine approaches. PMID:21366159

Segmental dilatation of the intestine.

PubMed

Ben Brahim, Mohamed; Belghith, Mohsen; Mekki, Mongi; Jouini, Riadh; Sahnoun, Lassaad; Maazoun, Kaies; Krichene, Imed; Golli, Mondher; Monastiri, Kamel; Nouri, Abdellatif

2006-06-01

The aim of this work is to discuss the pathogenesis of the segmental dilatation of the intestine (SDI) and to review its clinical presentation and the ways to confirm the diagnosis. Eight cases of pathologically proven SDI from 1987 to 2003 were reviewed and discussed. There were 7 newborns and a 1-year-old boy. Our patients are 5 boys and 3 girls. In all cases, the diagnosis was not suspected before surgery. Two patients presented with a low neonatal bowel obstruction. Six patients were operated for omphalocele, which was the most frequent associated malformation. The SDI involved the ileum in all patients. The treatment consisted on a resection of the dilated segment with an end-to-end anastomosis. Histological examination demonstrated the presence of ganglion cells in all cases. The muscular layer was hypertrophied in two cases and very thin in one case. A heterotopic gastric mucosa was observed in one case. No anomalies were observed in 5 cases. The postoperative course was uneventful in 6 cases with a mean follow-up of 5 years. Segmental intestinal dilatation is an exceptional pathology with an unknown etiology and a misleading clinical presentation. Several theories were proposed to explain this malformation; however, most authors are rather inclined to an embryological theory incriminating an extrinsic intrauterine intestinal compression. Most cases are neonatal discoveries. The clinical polymorphism and the lack of specificity of radiological investigations explain the difficulties to have a preoperative diagnosis. However, this difficulty is compensated by the favorable evolution after the resection of the dilated segment.

Alterations in atrial electrophysiology and tissue structure in a canine model of chronic atrial dilatation due to mitral regurgitation.

PubMed

Verheule, Sander; Wilson, Emily; Everett, Thomas; Shanbhag, Sujata; Golden, Catherine; Olgin, Jeffrey

2003-05-27

Clinically, chronic atrial dilatation is associated with an increased incidence of atrial fibrillation (AF), but the underlying mechanism is not clear. We have investigated atrial electrophysiology and tissue structure in a canine model of chronic atrial dilatation due to mitral regurgitation (MR). Thirteen control and 19 MR dogs (1 month after partial mitral valve avulsion) were studied. Dogs in the MR group were monitored using echocardiography and Holter recording. In open-chest follow-up experiments, electrode arrays were placed on the atria to investigate conduction patterns, effective refractory periods, and inducibility of AF. Alterations in tissue structure and ultrastructure were assessed in atrial tissue samples. At follow-up, left atrial length in MR dogs was 4.09+/-0.45 cm, compared with 3.25+/-0.28 at baseline (P<0.01), corresponding to a volume of 205+/-61% of baseline. At follow-up, no differences in atrial conduction pattern and conduction velocities were noted between control and MR dogs. Effective refractory periods were increased homogeneously throughout the left and right atrium. Sustained AF (>1 hour) was inducible in 10 of 19 MR dogs and none of 13 control dogs (P<0.01). In the dilated MR left atrium, areas of increased interstitial fibrosis and chronic inflammation were accompanied by increased glycogen ultrastructurally. Chronic atrial dilatation in the absence of overt heart failure leads to an increased vulnerability to AF that is not based on a decrease in wavelength.

[Tracheotomy-endoscop for dilatational percutaneous tracheotomy (TED)].

PubMed

Klemm, Eckart

2006-09-01

While surgical tracheotomies are currently performed using state-of-the-art operative techniques, percutaneous dilatational tracheostomy (PDT) is in a rapidly evolving state with regard to its technology and the number of techniques available. This has resulted in a range of new complications that are difficult to quantify on a scientific basis, given the fact that more than half of the patients who are tracheotomized in intensive care units die from their underlying disease. The new Tracheotomy Endoscope (TED) is designed to help prevent serious complications in dilatational tracheotomies and facilitate their management. The endoscope has been specifically adapted to meet the require-ments of percutaneous dilatational tracheotomies. It is fully compatible with all current techniques of PDT. The method is easy to learn. The percutaneous dilatational tracheotomy with the Tracheotomy Endoscope is a seven-step procedure: Advantages of the Tracheotomy Endoscope: Injuries to the posterior tracheal wall ar impossible (tracheoesophageal fistulas, pneumothorax). Minor bleeding sites on the tracheal mucosa can be controlled with a specially curved suction-coagulation tube introudeced through the Tracheotomy Endoscope. In cases with heavy bleeding and a risk of aspiration, the rigid indwelling Tracheotomy Endoscope provides a secure route for reintubating the patient with a cuffed endotracheal tube. It also allows for rapid conversion to an open surgical procedure if necessary. All the parts are easy to clean and are autoclavable. This type of endoscopically guided PDT creates an optimal link between the specialties of intensive care medicine and otorhinolaryngology. The Tracheotomy Endoscope (TED) increases the standard of safety in PDT.

UK guidelines on oesophageal dilatation in clinical practice

PubMed Central

Sami, Sarmed S; Haboubi, Hasan N; Ang, Yeng; Boger, Philip; Bhandari, Pradeep; de Caestecker, John; Griffiths, Helen; Haidry, Rehan; Patel, Praful; Paterson, Stuart; Ragunath, Krish; Watson, Peter; Siersema, Peter D; Attwood, Stephen E

2018-01-01

These are updated guidelines which supersede the original version published in 2004. This work has been endorsed by the Clinical Services and Standards Committee of the British Society of Gastroenterology (BSG) under the auspices of the oesophageal section of the BSG. The original guidelines have undergone extensive revision by the 16 members of the Guideline Development Group with representation from individuals across all relevant disciplines, including the Heartburn Cancer UK charity, a nursing representative and a patient representative. The methodological rigour and transparency of the guideline development processes were appraised using the revised Appraisal of Guidelines for Research and Evaluation (AGREE II) tool. Dilatation of the oesophagus is a relatively high-risk intervention, and is required by an increasing range of disease states. Moreover, there is scarcity of evidence in the literature to guide clinicians on how to safely perform this procedure. These guidelines deal specifically with the dilatation procedure using balloon or bougie devices as a primary treatment strategy for non-malignant narrowing of the oesophagus. The use of stents is outside the remit of this paper; however, for cases of dilatation failure, alternative techniques—including stents—will be listed. The guideline is divided into the following subheadings: (1) patient preparation; (2) the dilatation procedure; (3) aftercare and (4) disease-specific considerations. A systematic literature search was performed. The Grading of Recommendations Assessment, Develop­ment and Evaluation (GRADE) tool was used to evaluate the quality of evidence and decide on the strength of recommendations made. PMID:29478034

Congenital esophageal stenosis associated with esophageal atresia.

PubMed

McCann, F; Michaud, L; Aspirot, A; Levesque, D; Gottrand, F; Faure, C

2015-04-01

Congenital esophageal stenosis (CES) is a rare clinical condition but is frequently associated with esophageal atresia (EA). The aim of this study is to report the diagnosis, management, and outcome of CES associated with EA. Medical charts of CES-EA patients from Lille University Hospital, Sainte-Justine Hospital, and Montreal Children's Hospital were retrospectively reviewed. Seventeen patients (13 boys) were included. The incidence of CES in patients with EA was 3.6%. Fifteen patients had a type C EA, one had a type A EA, and one had an isolated tracheoesophageal fistula. Seven patients had associated additional malformations. The mean age at diagnosis was 11.6 months. All but two patients had non-specific symptoms such as regurgitations or dysphagia. One CES was diagnosed at the time of surgical repair of EA. In 12 patients, CES was suspected based on abnormal barium swallow. In the remaining four, the diagnostic was confirmed by esophagoscopy. Eleven patients were treated by dilation only (1-3 dilations/patient). Six patients underwent surgery (resection and anastomosis) because of failure of attempted dilations (1-7 dilations/patient). Esophageal perforation was encountered in three patients (18%). Three patients had histologically proven tracheobronchial remnants. CES associated with EA is frequent. A high index of suspicion for CES must remain in the presence of EA. Dilatation may be effective to treat some of them, but perforation is frequent. Surgery may be required, especially in CES secondary to ectopic tracheobronchial remnants. © 2014 International Society for Diseases of the Esophagus.

The relationship of systemic markers of renal function and vascular function with retinal blood vessel responses.

PubMed

Heitmar, R; Varma, C; De, P; Lau, Y C; Blann, A D

2016-11-01

To test the hypothesis of a significant relationship between systemic markers of renal and vascular function (processes linked to cardiovascular disease and its development) and retinal microvascular function in diabetes and/or cardiovascular disease. Ocular microcirculatory function was measured in 116 patients with diabetes and/or cardiovascular disease using static and continuous retinal vessel responses to three cycles of flickering light. Endothelial function was evaluated by von Willebrand factor (vWf), endothelial microparticles and soluble E selectin, renal function by serum creatinine, creatinine clearance and estimated glomerular filtration rate (eGFR). HbA1c was used as a control index. Central retinal vein equivalence and venous maximum dilation to flicker were linked to HbA1c (both p < 0.05). Arterial reaction time was linked to serum creatinine (p = 0.036) and eGFR (p = 0.039); venous reaction time was linked to creatinine clearance (p = 0.018). Creatinine clearance and eGFR were linked to arterial maximum dilatation (p < 0.001 and p = 0.003, respectively) and the dilatation amplitude (p = 0.038 and p = 0.048, respectively) responses in the third flicker cycle. Of venous responses to the first flicker cycle, HbA1c was linked to the maximum dilation response (p = 0.004) and dilatation amplitude (p = 0.017), vWf was linked to the maximum constriction response (p = 0.016), and creatinine clearance to the baseline diameter fluctuation (p = 0.029). In the second flicker cycle, dilatation amplitude was linked to serum creatinine (p = 0.022). Several retinal blood vessel responses to flickering light are linked to glycaemia and renal function, but only one index is linked to endothelial function. Renal function must be considered when interpreting retinal vessel responses.

Deformation mechanisms of idealised cermets under multi-axial loading

NASA Astrophysics Data System (ADS)

Bele, E.; Goel, A.; Pickering, E. G.; Borstnar, G.; Katsamenis, O. L.; Pierron, F.; Danas, K.; Deshpande, V. S.

2017-05-01

The response of idealised cermets comprising approximately 60% by volume steel spheres in a Sn/Pb solder matrix is investigated under a range of axisymmetric compressive stress states. Digital volume correlation (DVC) anal`ysis of X-ray micro-computed tomography scans (μ-CT), and the measured macroscopic stress-strain curves of the specimens revealed two deformation mechanisms. At low triaxialities the deformation is granular in nature, with dilation occurring within shear bands. Under higher imposed hydrostatic pressures, the deformation mechanism transitions to a more homogeneous incompressible mode. However, DVC analyses revealed that under all triaxialities there are regions with local dilatory and compaction responses, with the magnitude of dilation and the number of zones wherein dilation occurs decreasing with increasing triaxiality. Two numerical models are presented in order to clarify these mechanisms: (i) a periodic unit cell model comprising nearly rigid spherical particles in a porous metal matrix and (ii) a discrete element model comprising a large random aggregate of spheres connected by non-linear normal and tangential "springs". The periodic unit cell model captured the measured stress-strain response with reasonable accuracy but under-predicted the observed dilation at the lower triaxialities, because the kinematic constraints imposed by the skeleton of rigid particles were not accurately accounted for in this model. By contrast, the discrete element model captured the kinematics and predicted both the overall levels of dilation and the simultaneous presence of both local compaction and dilatory regions with the specimens. However, the levels of dilation in this model are dependent on the assumed contact law between the spheres. Moreover, since the matrix is not explicitly included in the analysis, this model cannot be used to predict the stress-strain responses. These analyses have revealed that the complete constitutive response of cermets depends both on the kinematic constraints imposed by the particle aggregate skeleton, and the constraints imposed by the metal matrix filling the interstitial spaces in that skeleton.

Impact of pregnancy on autograft dilatation and aortic valve function following the Ross procedure.

PubMed

Carvajal, Horacio G; Lindley, Kathryn J; Shah, Trupti; Brar, Anoop K; Barger, Philip M; Billadello, Joseph J; Eghtesady, Pirooz

2018-03-01

The effects of pregnancy on autograft dilatation and neoaortic valve function in patients with a Ross procedure have not been studied. We sought to evaluate the effect of pregnancy on autograft dilatation and valve function in these patients with the goal of determining whether pregnancy is safe after the Ross procedure. A retrospective chart review of female patients who underwent a Ross procedure was conducted. Medical records for 51 patients were reviewed. Among the 33 patients who met inclusion criteria, 11 became pregnant after surgery and 22 did not. Echocardiographic reports were used to record aortic root diameter and aortic insufficiency before, during, and after pregnancy. Patient's charts were reviewed for reinterventions and complications. Primary endpoints included reinterventions, aortic root dilation of ≥5 cm, aortic insufficiency degree ≥ moderate, and death. There were 18 pregnancies carried beyond 20 weeks in 11 patients. There was no significant difference in aortic root diameter between nulliparous patients and parous patients prior to their first pregnancy (3.53 ± 0.44 vs 3.57 ± 0.69 cm, P = .74). There was no significant change in aortic root diameter after first pregnancy (3.7 ± 0.4 cm, P = .056) although there was significant dilatation after the second (4.3 ± 0.7 cm, P = .009) and third (4.5 ± 0.7 cm, P = .009) pregnancies. Freedom from combined endpoints was significantly higher for patients in the pregnancy group than those in the nonpregnancy group (P = .002). Pregnancy was not associated with significantly increased adverse events in patients following the Ross procedure. Special care should be taken after the first pregnancy, as multiparity may lead to increased neoaortic dilatation. © 2017 Wiley Periodicals, Inc.

Long term impact of balloon post-dilatation on neointimal formation: an experimental comparative study between second-generation self-expanding versus balloon-expandable stent technologies.

PubMed

Aboodi, Michael S; Milewski, Krzysztof; Tellez, Armando; Cheng, Yanping; Yi, Geng-Hua; Kaluza, Greg L; Granada, Juan F

2014-02-15

Background: Self-expanding stents (SES) are reemerging as therapeutic alternatives to treat coronary artery disease. It has been proposed that SES can improve clinical outcomes by inducing less injury at implantation and achieving better vessel wall apposition.To date, little data exists comparing the vascular response to both methods of deployment in a controlled experimental setting. Objective: To quantify differences in vascular injury and healing between second-generation SES and balloon-expandable stents (BES) and the effects of balloon post-dilatation in a porcine coronary model. Methods: Seventy-five bare SES (AXXESS or vProtect) and 42 BES (Vision) were implanted in porcine coronaries. A subset of these received balloon post-dilatation(SES 1 D 5 22, BES 1 D 5 20). Follow-up was scheduled at 30 (BES 5 10, BES 1 D 56, SES 5 19, SES 1 D 5 8), 90 (BES 5 6, BES 1 D 5 8, SES 5 19, SES 1 D 5 8), and 180 days (BES 5 6, BES 1 D 5 6, SES 5 15, SES 1 D 5 6). Results: In vivo imaging and histological analysis showed that neointimal formation peaks early (30 days) in BES. Conversely, for SES, the peak occurred later (90 days). However, the neointimal formation achieved in either group equalized at 180 days. For SES, post-dilatation shortened the peak of neointimal formation to 30 days. Conversely, for BES, post-dilatation delayed the peak of neointimal formation to 90 days. At 30 days, histology showed that SES had significantly less injury. However, at 90 days, injury scores tended to be higher for SES. By 180 days, injury scores were comparable between both groups. Conclusions: The mechanism of stent expansion influences the degree of vascular injury and healing. The synergistic use of balloon post dilatation changes the dynamics of healing and may impact the potential beneficial effects inherent to SES technologies.

Long-term, low-dose prophylaxis against urinary tract infections in young children.

PubMed

Brandström, Per; Hansson, Sverker

2015-03-01

Urinary tract infection (UTI) affects about 2 % of boys and 8 % of girls during the first 6 years of life with Escherichia coli as the predominant pathogen. Symptomatic UTI causes discomfort and distress, and carries a risk of inducing renal damage. The strong correlation between febrile UTI, dilating vesicoureteral reflux (VUR), and renal scarring led to the introduction of antibiotic prophylaxis for children with VUR to reduce the rate of UTI recurrence. It became common practice to use prophylaxis for children with VUR and other urinary tract abnormalities. This policy has been challenged because of a lack of scientific support. Now, randomized controlled studies are available that compare prophylaxis to no treatment or placebo. They show that children with normal urinary tracts or non-dilating VUR do not benefit from prophylaxis. Dilating VUR may still be an indication for prophylaxis in young children. After the first year of life, boys have very few recurrences and do not benefit from prophylaxis. Girls with dilating VUR, on the other hand, are more prone to recurrences and benefit from prophylaxis. There has been a decline in the use of prophylaxis due to questioning of its efficacy, increasing bacterial resistance, and a propensity to low adherence to medication. Alternative measures to reduce UTI recurrences should be emphasized. However, in selected patients carefully followed, prophylaxis can protect from recurrent UTI and long-term sequelae. 1. There is a strong correlation between UTI, VUR, and renal scarring. 2. Children with normal urinary tracts or non-dilating VUR do not benefit from prophylaxis. 3. Young children, mainly girls, with dilating VUR are at risk of recurrent UTI and acquired renal scarring and seem to gain from antibiotic prophylaxis. 4. Increasing bacterial resistance and low adherence with prescribed medication is a major obstacle to successful antibiotic prophylaxis.

Excessive urinary tract dilatation and proteinuria in pregnancy: a common and overlooked association?

PubMed

Piccoli, Giorgina B; Attini, Rossella; Parisi, Silvia; Vigotti, Federica N; Daidola, Germana; Deagostini, Maria Chiara; Ferraresi, Martina; De Pascale, Agostino; Porpiglia, Francesco; Veltri, Andrea; Todros, Tullia

2013-02-27

Proteinuria and dilatation of the urinary tract are both relatively common in pregnancy, the latter with a spectrum of symptoms, from none to severe pain and infection. Proteinuria is a rare occurrence in acute obstructive nephropathy; it has been reported in pregnancy, where it may pose a challenging differential diagnosis with pre-eclampsia.The aim of the present study is to report on the incidence of proteinuria (≥ 0.3; ≥ 0.5 g/day) in association with symptomatic-severe urinary tract dilatation in pregnancy. Case series. Nephrological-Obstetric Unit dedicated to pregnancy and kidney diseases (January 2000-April 2011). database prospectively updated since the start of the Unit. Retrospective review of clinical charts identified as relevant on the database, by a nephrologist and an obstetrician. From January 2000 to April 2011, 262 pregnancies were referred. Urinary tract dilatation with or without infection was the main cause of referral in 26 cases (predominantly monolateral in 19 cases): 23 singletons, 1 lost to follow-up, 1 twin and 1 triplet. Patients were referred for urinary tract infection (15 cases) and/or renal pain (10 cases); 6 patients were treated by urologic interventions ("JJ" stenting). Among them, 11 singletons and 1 triple pregnancy developed proteinuria ≥ 0.3 g/day (46.1%). Proteinuria was ≥ 0.5 g/day in 6 singletons (23.1%). Proteinuria resolved after delivery in all cases. No patient developed hypertension; in none was an alternative cause of proteinuria evident. No significant demographic difference was observed in patients with renal dilatation who developed proteinuria versus those who did not. An association with the presence of "JJ" stenting was present (5/6 cases with proteinuria ≥ 0.5 g/day), which may reflect both severer obstruction and a role for vescico-ureteral reflux, induced by the stent. Symptomatic urinary tract dilatation may be associated with proteinuria in pregnancy. This association should be kept in mind in the differential diagnosis with other causes of proteinuria in pregnancy, including pre-eclampsia.

En face choroidal vascular feature imaging in acute and chronic central serous chorioretinopathy using swept source optical coherence tomography.

PubMed

Lee, Won June; Lee, Jung Wook; Park, Seung Hun; Lee, Byung Ro

2017-05-01

To evaluate the variable depth tomographic features of choroidal vasculature in acute and chronic central serous chorioretinopathy (CSC) using swept source optical coherence tomography (SS-OCT) en face imaging. We retrospectively reviewed the en face SS-OCT images of 29 patients that presented with acute (12 eyes) or chronic (17 eyes) CSC. All of the patient eyes underwent 6×6 macular scans with SS-OCT (DRI OCT-1, Topcon, Tokyo, Japan), fluorescein angiography and indocyanine green angiography. The en face image was used to investigate the choroidal vasculature of each layer. Moreover, we determined that some parts corresponded to choriocapillaris and Sattler's layer attenuation, whereas choroidal vessel dilatation was associated with Haller's layer. At Haller's layer level, choroidal vessel dilatation was observed in 11 of 12 acute CSC (91.7%) and 15 of 17 chronic CSC (88.2%). In acute CSC, choroidal vessel dilatation was divided into focal (9/11; 81.8%) and diffuse (2/11; 18.2%) patterns. The chronic CSC cases demonstrated different patterns of choroidal vessel dilatation: focal (5/15; 33.3%) and diffuse (10/15; 66.6%). Ten of the acute CSC eyes (83.3%) and 14 of the chronic CSC eyes (82.4%) were found to have obscured choriocapillaris and Sattler's layers on en face imaging. En face imaging of SS-OCT is useful when combined with angiography in CSC for evaluating choroidal vessel dilatation at Haller's layer and to identify obscured upper layers. We identified different choroidal vessel dilatation patterns between acute and chronic CSC. These findings might be useful for pathophysiological understanding of CSC. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Combining Segmented Grey and White Matter Images Improves Voxel-based Morphometry for the Case of Dilated Lateral Ventricles.

PubMed

Goto, Masami; Abe, Osamu; Aoki, Shigeki; Kamagata, Koji; Hori, Masaaki; Miyati, Tosiaki; Gomi, Tsutomu; Takeda, Tohoru

2018-01-18

To evaluate the error in segmented tissue images and to show the usefulness of the brain image in voxel-based morphometry (VBM) using Statistical Parametric Mapping (SPM) 12 software and 3D T 1 -weighted magnetic resonance images (3D-T 1 WIs) processed to simulate idiopathic normal pressure hydrocephalus (iNPH). VBM analysis was performed on sagittal 3D-T 1 WIs obtained in 22 healthy volunteers using a 1.5T MR scanner. Regions of interest for the lateral ventricles of all subjects were carefully outlined on the original 3D-T 1 WIs, and two types of simulated 3D-T 1 WI were also prepared (non-dilated 3D-T 1 WI as normal control and dilated 3D-T 1 WI to simulate iNPH). All simulated 3D-T 1 WIs were segmented into gray matter, white matter, and cerebrospinal fluid images, and normalized to standard space. A brain image was made by adding the gray and white matter images. After smoothing with a 6-mm isotropic Gaussian kernel, group comparisons (dilated vs non-dilated) were made for gray and white matter, cerebrospinal fluid, and brain images using a paired t-test. In evaluation of tissue volume, estimation error was larger using gray or white matter images than using the brain image, and estimation errors in gray and white matter volume change were found for the brain surface. To our knowledge, this is the first VBM study to show the possibility that VBM of gray and white matter volume on the brain surface may be more affected by individual differences in the level of dilation of the lateral ventricles than by individual differences in gray and white matter volumes. We recommend that VBM evaluation in patients with iNPH should be performed using the brain image rather than the gray and white matter images.

Differences in stone size and ureteral dilation between obstructing proximal and distal ureteral calculi.

PubMed

Eisner, Brian H; Pedro, Renato; Namasivayam, Saravanan; Kambadakone, Avinash; Sahani, Dushyant V; Dretler, Stephen P; Monga, Manoj

2008-09-01

To examine the differences in ureteral dilation and calculus size between obstructing proximal and distal ureteral stones. A retrospective review of computed tomography (CT) scans from 176 consecutive patients with obstructing ureteral calculi was performed. For the calculi, the axial diameter was defined as the largest stone diameter on the axial CT images, and the coronal length was defined as the cephalocaudal length of the stone measured on the coronal CT images. Univariate and multivariate statistical analyses were performed. A total of 65 proximal and 111 distal ureteral calculi were analyzed. On univariate analysis, the proximal calculi were associated with a greater degree of ureteral dilation (mean 6.1 mm vs 5.3 mm, P = .01) and had a greater coronal length (mean 9.9 mm vs 8.3 mm, P = .005) than distal calculi. This association was also true on the multivariate analysis, which controlled for age and sex (P = .0004). No statistically significant difference was found in the axial calculus diameter for the proximal and distal stones (mean 5.3 mm vs 5.0 mm, P = .29). In a subset of 50 patients whose contralateral ureters (without stones) were measured for control comparison, the ureteral dilation in the ureters with stones was significantly greater than in the control ureters (proximal ureter 6.2 mm vs 4.3 mm, P = .001; distal ureter 4.7 mm vs 3.8 mm, P = .004). For proximal calculi, 72.3% were associated with ureteral dilation of less than 7 mm, 23.1% with 7-10 mm, and 4.6% with greater than 10 mm. For the distal calculi, 90.1% were associated with ureteral dilation of less than 7 mm, 6.3% with 7-10 mm, and 3.6% with greater than 10 mm. The coronal length was the largest measured diameter in 94% of the calculi, and the mean calculus coronal length was significantly greater than the mean axial diameter (8.9 mm vs 5.1 mm, respectively, P < .001). The results of our study have shown that proximal ureteral calculi are associated with a significantly greater degree of ureteral dilation and larger coronal length than are distal calculi. These findings should guide the endoscopist in planning intracorporeal ureteroscopic lithotripsy. We suggest obtaining CT coronal images to more accurately characterize obstructing ureteral stones.

Mitomycin C and the endoscopic treatment of laryngotracheal stenosis: are two applications better than one?

PubMed

Smith, Marshall E; Elstad, Mark

2009-02-01

Endoscopic treatment of laryngotracheal stenosis by airway dilation, despite short-term improvement, is often associated with long-term relapse. Mitomycin-C (MMC) inhibits fibroblast proliferation and synthesis of extracellular matrix proteins, and thereby modulates wound healing and scarring. MMC application at the time of endoscopic dilation and laser surgery has been suggested to improve outcomes, but this has not been studied in a rigorous manner. This study examines the hypothesis that two topical applications of MMC given 3-6 weeks apart will result in decreased scarring/restenosis of the airway, when compared to a single topical application. A randomized, prospective, double-blind, placebo-controlled clinical trial. Twenty-six patients with laryngotracheal stenosis due to idiopathic subglottic stenosis, postintubation stenosis, or Wegener's granulomatosis entered a protocol to receive three endoscopic CO(2) laser and dilation procedures over a 3-month interval. At the first procedure, after radial CO(2) laser incision and airway dilation, all patients received topical application of MMC (0.5 mg/mL) to the airway lesion. One month later, a second endoscopic incision and dilation was performed and the patients were randomized to either a second application of mitomycin-C or to application of saline placebo. A third dilation procedure was performed 2 months later, without MMC application. Patients were followed for up to 5 years for relapse of airway stenosis with clinical symptoms sufficient to require a subsequent procedure. The relapse rates at 1, 3, and 5 years were 7%, 36%, and 69% for patients treated with two applications of MMC compared to 33%, 58%, and 70% for patients treated with one application of MMC. The median interval to relapse was 3.8 years in the two-application group, compared with 2.4 years in the one-application group. This prospective randomized double-blind placebo-controlled trial suggests that, in the endoscopic management of laryngotracheal stenosis, two applications of MMC given 3-4 weeks apart after airway radial incision and dilation reduces the restenosis rate for 2 to 3 years after treatment when compared to a single application. However, restenosis and delayed symptom recurrence continues so that at 5 years the relapse rates are the same. Thus, MMC may postpone, but does not prevent, the recurrence of symptomatic stenosis in the majority of patients.

[Value of MR imaging in the diagnosis of intraductal papillary neoplasm of the bile duct].

PubMed

Song, Fengxiang; Zhou, Jun; Shi, Yuxin; Zeng, Mengsu; Zhou, Kangrong; Ding, Yuqin; Cao, Yingli; Zhou, Jianjun

2015-01-01

To analyze the value of MR imaging in diagnosis of intraductal papillary neoplasm of the bile duct (IPN-B). Fourteen patients with intraductal papillary neoplasms of the bile duct confirmed by surgical pathology were included in this study. The patients underwent MR routine plain scanning and enhancement scanning (including T1WI, T2WI with fat suppression, FALSH T1WI, and three-phase enhancement scanning), diffusion weighted imaging(DWI) and magnetic resonance cholangiopancreatography (MRCP) before operation. The imaging data were reviewed and analyzed retrospectively in comparison with the surgical and pathological results. In these patients, 7 cases had tumors located in the left lobe, 2 cases had tumors in both the left and right lobes, 2 cases in the hepatic hilum, 2 cases in the common bile duct, and 1 case in both the right lobe and the common bile duct. Solitary or multiple intraductal masses could be found in 12 cases, with 11 cases appeared as papillary masses and one case as flat mass. In the other two cases the tumor was not visible (one case had too many stones, and in another case the tumor was too small). The tumors in the 12 cases showed hypointensity on T1WI and hyperintensity on T2WI. On the dynamic contrast-enhanced MRI, 11 cases showed mild and one showed moderate enhancement in arterial phase, and all the cases showed mildly and gradually delayed enhancement. On DWI, the lesion areas showed high signal intensity in all the cases, and the ADC value of the tumor area (1.697×10(-3)mm(2)/s) was significantly lower than that of the normal bile (3.973×10(-3)mm(2)/s) (t = -10.94, P < 0.05). Twelve cases demonstrated filling defects on primary MRCP coronary thin section images. On 3D-reconstruction MRCP images, 7 cases exhibited diffuse bile duct dilatation with the tumor areas more prominent, 3 cases exhibited aneurysmal bile dilatation, while the rest 4 cases exhibited segmental or lobar bile duct dilatation ( including 2 with invisible tumors ). In the 3 cases with aneurysmal bile dilatation, the multiple directions of MRCP images helped to find the communication between the aneurysmal dilatation and the bile duct. All the cases showed significant proximal bile duct dilatation (the extent of dilatation >100%), and 9 cases also showed distal bile duct dilatation. Bile duct stones were noted in 6 cases, 4 at the tumor area, and the other 2 away from the tumor area. No adjacent tissue invasion and no distal tissue or lymph node metastasis were observed. Intraductal papillary neoplasms of the bile ducts have characteristic imaging appearances on MRI, and MRI is an important method helpful to making correct diagnosis.

Does self-administered vaginal misoprostol result in cervical ripening in postmenopausal women after 14 days of pre-treatment with estradiol? Trial protocol for a randomised, placebo-controlled sequential trial.

PubMed

Oppegaard, K S; Lieng, M; Berg, A; Istre, O; Qvigstad, E; Nesheim, B-I

2008-06-01

To compare the impact of 1000 micrograms of self-administered vaginal misoprostol versus self-administered vaginal placebo on preoperative cervical ripening after pre-treatment with estradiol vaginal tablets at home in postmenopausal women prior to day-care operative hysteroscopy. Randomised double-blind placebo-controlled sequential trial. The boundaries for the sequential trial were calculated on the primary outcomes of a difference of cervical dilatation > or = 1 millimetre, with the assumption of a type 1 error of 0.05 and a power of 0.95. Norwegian university teaching hospital. Postmenopausal women referred for day-care operative hysteroscopy. The women were randomised to either 1000 micrograms of self-administered vaginal misoprostol or self-administered vaginal placebo the evening before day-care operative hysteroscopy. All women had administered a 25-microgram vaginal estradiol tablet daily for 14 days prior to the operation. Preoperative cervical dilatation (difference between misoprostol and placebo group, primary outcome), difference in dilatation before and after administration of misoprostol or placebo, number of women who achieve a preoperative cervical dilatation > or = 5 millimetres, acceptability, complications and side effects (secondary outcomes). Intra-operative findings and distribution of cervical dilatation in the two treatment groups: values are given as median (range) or n (%). Difference in dilatation before and after administration of misoprostol and placebo: values are given as median (range) of intraindividual differences. Percentage of women who achieve a cervical dilatation of > or = 5 mm, percentage of women who were difficult to dilate. Acceptability in the two treatment groups: values are given as completely acceptable n (%), fairly acceptable n (%), fairly unacceptable n (%), completely unacceptable n (%). Pain in the two treatment groups: pain was measured with a visual analogue scale ranging from 0 (no pain) to 10 (unbearable pain): values are given as median (range). Occurrence of side effects in the two treatment groups. Values are given as n (%). Complications given as n (%). No pharmaceutical company was involved in this study. A research grant from the regional research board of Northern Norway has been awarded to finance Dr K.S.O.'s leave from Hammerfest hospital as well as travel expenses between Hammerfest and Oslo, and research courses. The research grant from Prof B.I.N. (Helse Øst) funded the purchase of estradiol tablets, the manufacturing costs of misoprostol and placebo capsules from the hospital pharmacy, as well as the costs incurred for preparing the randomisation schedule and distribution of containers containing capsules to hospital. Prof B.I.N.'s research grant also funded insurance for the study participants. Estimated completion date 31 December 2008.

Compressibility Effects on the Passive Scalar Flux Within Homogeneous Turbulence

NASA Technical Reports Server (NTRS)

Blaisdell, G. A.; Mansour, N. N.; Reynolds, W. C.

1994-01-01

Compressibility effects on turbulent transport of a passive scalar are studied within homogeneous turbulence using a kinematic decomposition of the velocity field into solenoidal and dilatational parts. It is found that the dilatational velocity does not produce a passive scalar flux, and that all of the passive scalar flux is due to the solenoidal velocity.

Barriers to Eye Care Faced by Adult Hispanics with Diabetes

ERIC Educational Resources Information Center

Griffin-Shirley, Nora; Trusty, Sharon; Kelley, Emily; Siew-Jin, Lai Keun; Macias, Eduardo P.

2004-01-01

Current diabetes vision care guidelines suggest that people receive at least an annual dilated eye examination 5 years after the diagnosis of Type I diabetes and a dilated eye examination at the time of diagnosis of Type II diabetes, and at least annually thereafter. Hispanics in the United States have a three-fold greater prevalence of diabetes…

Bile peritonitis associated with gastric dilation-volvulus in a dog

PubMed Central

2005-01-01

Abstract This report describes a case of septic peritonitis and gall bladder rupture in German shepherd dog that developed 7 d after surgical treatment for gastric dilation-volvulus. Histological examination confirmed gall bladder necrosis, secondary to an acute ischemic event. Postoperative acute necrotizing cholecystitis has not been a previously reported complication in dogs. PMID:15884650

Endoscopic Pneumatic Dilation for Esophageal Achalasia.

PubMed

Markar, Sheraz; Zaninotto, Giovanni

2018-04-01

Pneumatic dilation is a well-established treatment modality that has withstood the test of time. Prospective and randomized trials have shown that in expert hands, it provides results similar to a laparoscopic Heller myotomy with fundoplication. In addition, it should be considered the primary form of treatment in patients who experience recurrence of symptoms after a surgical myotomy.

[A treatment to serious esophageal cicatrices stenosi by metal and silica gel dilator].

PubMed

Li, J; Chen, X; Sun, C; Liu, H

1999-12-01

To find an effective method of treating the esophageal cicatricial stenosis. Six cases with esophageal cicatricial stenosis were treated by mental and silica gel dilator. The effects in all six cases were satisfactory and no any complications were finded. The method is safe, effective and of no complications, the treatment time is shorter also.

A Simple Band for Gastric Banding.

PubMed

Broadbent

1993-08-01

The author has noted that flexible gastric bands have occasionally stenosed the gastric stoma or allowed it to dilate. A band was developed using a soft outer silicone rubber tube over a holding mechanism made out of a nylon cable tie passed within the silicone tube. This simple, easily applied band is rigid, resisting scar contracture and dilatation.

A large left ventricular thrombus.

PubMed

Patanè, Salvatore; Marte, Filippo

2009-06-26

The discovery of a left ventricular mass obliges the clinician to perform a differential diagnosis including tumour or lipoma versus thrombus and its assessment presents important clinical implications. Dilated cardiomyopathy has been associated with left ventricular thrombosis which leads to substantial morbidity and mortality as a site for peripheral emboli. There are some studies on patients with dilated cardiomyopathy showing altered hemostasis and platelet behavior despite sinus rhythm. An increased incidence of thromboembolism is also well recognized in patients with left ventricular systolic dysfunction complicating history of myocardial infarction. Clinical dilemmas in treating left ventricular thrombus have been described too. We present a case of a large mobile left ventricular thrombus in a 71-year-old Italian man with dilated cardiomyopathy and history of myocardial infarction.

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

Itai, Y.; Araki, T.; Furui, S.

Fifteen patients with primary intrahepatic biliary malignancy (cholangiocarcinoma in 13, biliary cystadenocarcinoma in two) were examined by computed tomography (CT). The CT features were classified into three types: (A) a well-defined round cystic mass with internal papillary projections, (B) a localized intrahepatic biliary dilatation without a definite mass lesion, and (C) miscellaneous low-density masses. Intraphepatic biliary dilatation was noted in all cases of Types A and B and half of those of Type C; dilatation of extrahepatic bile ducts occurred in 4/4, 1/3, and 0/8, respectively. CT patterns, such as a well-defined round cystic mass with papillary projections or dilatationmore » of intra- and extrahepatic ducts, give important clues leading to a correct diagnosis of primary intrahepatic biliary malignancy.« less

Transthoracic ultrasound guided balloon dilation of cor triatriatum dexter in 2 Rottweiler puppies.

PubMed

Birettoni, F; Caivano, D; Bufalari, A; Giorgi, M E; Miglio, A; Paradies, P; Porciello, F

2016-12-01

Balloon dilation was performed in two Rottweiler puppies with cor triatriatum dexter and clinical signs of ascites using transthoracic echocardiographic guidance. The dogs were positioned on a standard echocardiography table in right lateral recumbency, and guide wires and balloon catheters were imaged by echocardiographic views optimized to allow visualization of the defect. The procedures were performed successfully without complications and clinical signs were resolved completely in both cases. Guide wires and balloon catheters appeared hyperechoic on transthoracic echocardiography image and could be clearly monitored and guided in real-time. These two cases demonstrate that it is possible to perform balloon catheter dilation of cor triatriatum dexter under transthoracic guidance alone. Copyright © 2016 Elsevier B.V. All rights reserved.

Direct simulation of compressible turbulence in a shear flow

NASA Technical Reports Server (NTRS)

Sarkar, S.; Erlebacher, G.; Hussaini, M. Y.

1991-01-01

The purpose of this study is to investigate compressibility effects on the turbulence in homogeneous shear flow. It is found that the growth of the turbulent kinetic energy decreases with increasing Mach number, a phenomenon similar to the reduction of turbulent velocity intensities observed in experiments on supersonic free shear layers. An examination of the turbulent energy budget shows that both the compressible dissipation and the pressure-dilatation contribute to the decrease in the growth of kinetic energy. The pressure-dilatation is predominantly negative in homogeneous shear flow, in contrast to its predominantly positive behavior in isotropic turbulence. The different signs of the pressure-dilatation are explained by theoretical consideration of the equations for the pressure variance and density variance.