Generation of Realistic Physical Models of Cerebral Aneurysms for In Vitro Flow Visualisation

2009 ◽  
Author(s):  
Paul Fahy ◽  
Tim McGloughlin ◽  
Patrick Delassus ◽  
Liam Morris
Keyword(s):  
Treatment Options ◽  
Cerebral Aneurysms ◽  
Physical Models ◽  
Endovascular Coiling ◽  
Flow Visualisation ◽  
Cerebral Vasculature ◽  
Surgical Clipping ◽  
The Media ◽  
Media Layer

An aneurysm is a localised persistent dilation of the blood vessel wall. Aneurysm formation is hypothesised to be a consequence of haemodynamically generated forces working on the arterial wall leading to degeneration of the media layer (1). This focal degeneration typically occurs at curved arterial segments and at bifurcation points around the circle of Willis. Intracranial aneurysms are traditionally classified by aetiology and morphology. The majority are idiopathic and saccular. It is estimated that 1.5–6% of the general population have or will develop an intracranial aneurysm, predominantly occurring in women, most of them being asymptomatic (1). If left undetected these aneurysms may rupture with a 30 day mortality rate of 45% (1). There are two treatment options surgical clipping or endovascular coiling. Both of these techniques exclude the aneurysm from the normal circulation. Endovascular coiling is preferred due to its minimally invasive nature. Numerous studies have been done so far based on idealized glass models and using FVM, FEA methods, but very little testing has been carried out on devices using realistic silicone models. This is mainly because of the complexity of the cerebral vasculature. Silicone replicas of both realistic and idealised models were manufactured based on CT scans and anatomical dimensions obtained from literature, respectively (2).

Influence of Stent Configuration on Cerebral Aneurysm Fluid Dynamics

2010 ◽  
Author(s):  
Haithem Babiker ◽  
L. Fernando Gonzalez ◽  
Felipe Albuquerque ◽  
Daniel Collins ◽  
Arius Elvikis ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Treatment Option ◽  
Treatment Options ◽  
Cerebral Aneurysms ◽  
Endovascular Coiling ◽  
Invasive Technique ◽  
Surgical Clipping ◽  
The Past ◽  
Alternative Treatment Option ◽  
Wide Neck

Treatment options for cerebral aneurysms have drastically evolved in the last decade. In the past, surgical clipping through craniotomy was the predominant treatment option for cerebral aneurysms. Presently, endovascular coiling, a minimally invasive technique, has superseded clipping in many centers [1]. However, the coiling of wide-neck aneurysms is still a challenge [2]. Complete aneurysmal occlusion is often impossible [3]. Recently, stand-alone stents have been explored as an alternative treatment option for wide-neck aneurysms [4].

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

2014 ◽  
Vol 14 (1) ◽  
pp. 23-30 ◽  
Author(s):  
Aws Alawi ◽  
Randall C. Edgell ◽  
Samer K. Elbabaa ◽  
R. Charles Callison ◽  
Yasir Al Khalili ◽  
...  
Keyword(s):  
Hospital Mortality ◽  
Coil Embolization ◽  
Aneurysmal Subarachnoid Hemorrhage ◽  
Cerebral Aneurysms ◽  
Endovascular Coiling ◽  
Complication Rates ◽  
Surgical Clipping ◽  
Treatment Groups ◽  
Risk Of Death ◽  
Inpatient Database

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

scholarly journals Inflammation in Murine Aneurysm Healing: The Role of CXCL1

Neurosurgery ◽  
2019 ◽  
Vol 66 (Supplement_1) ◽  
Author(s):  
Devan Patel ◽  
Kartik Motwani ◽  
Koji Hosaka ◽  
Brian L Hoh
Keyword(s):  
Data Collection ◽  
Cerebral Aneurysm ◽  
Treatment Options ◽  
Neutralizing Antibody ◽  
Neutrophil Infiltration ◽  
Flow Chamber ◽  
Aneurysm Rupture ◽  
Endovascular Coiling ◽  
The Right

Abstract INTRODUCTION Cerebral aneurysm rupture results in subarachnoid hemorrhage which has a mortality of up to 40%. Current prophylactic treatment options include surgical clipping, flow diversion, and endovascular coiling. A significant drawback of coiling is that up to 20% of aneurysms recur and require retreatment due to insufficient fibrotic healing. Thus, it is crucial to develop more effective treatments. As inflammation appears to be critical in cerebral aneurysm pathophysiology, it is necessary to investigate aneurysm healing in the context of key inflammatory mediators. Using a novel in Vitro flow chamber model, we found increased expression of CXCL1, a neutrophil chemoattractant, at arterial bifurcations and in aneurysms. We hypothesized that CXCL1 is a key mediator in aneurysm healing. METHODS Using our murine aneurysm healing model, aneurysms were created in the right common carotid artery of female C57BL/6 mice using elastase. Three weeks later, aneurysms were implanted with either poly (lactic-co-glycolic acid) (PLGA) + CXCL1—coated coils or PLGA only—coated coils. Three weeks after coil implantation, aneurysms were harvested for data collection. In a subsequent experiment, the same aneurysm model was used but all mice were coiled with PLGA-coated coils. Animals were randomly assigned to receive intraperitoneal injections of either CXCL1 neutralizing antibody or IgG control. Three weeks after coiling, aneurysms were harvested for data collection. RESULTS Animals treated with PLGA + CXCL1—coated coils had significantly decreased aneurysm healing than those treated with PLGA only—coated coils (21.8% vs 39.8%, P = .048). Animals treated with CXCL1 neutralizing antibody had significantly increased aneurysm healing compared to IgG control (63.8% vs 42.4%, P = .00012). CXCL1 neutralizing antibody also decreased neutrophil infiltration into the aneurysm compared to IgG control (2.0 cells/hpf vs 5.4 cells/hpf, P = .03). CONCLUSION Our findings suggest CXCL1 decreases murine aneurysm healing after coil implantation. Therapeutic intervention with CXCL1 neutralizing antibody appears to increase aneurysm healing by decreasing neutrophil infiltration.

Surgical Clipping vs Endovascular Coiling for Newly Diagnosed and Recurrent Cerebral Aneurysms: an Update on the Current Literature. Single-Center Case Series

2018 ◽  
Vol 2 (1) ◽  
pp. 16-21
Author(s):  
F. Salle ◽  
A. Jaume ◽  
G. Castelluccio ◽  
E. Spagnuolo
Keyword(s):  
Intracranial Aneurysms ◽  
Young Patients ◽  
Case Series ◽  
Cerebral Aneurysms ◽  
Endovascular Coiling ◽  
Newly Diagnosed ◽  
Review Of The Literature ◽  
Surgical Experience ◽  
Surgical Clipping ◽  
The Ideal

Abstract The ideal treatment for intracranial aneurysms has been highly controversial in the last few decades. It is particularly difficult to decide between clipping vs. coiling when it comes to an aneurysm that has already been treated. The authors performed a review of the literature published in the last ten years amongst the main neurosurgical publications and make recommendations based on this evidence and the surgical experience of the eldest author of this paper (ES). A series of cases of recurrent, incompletely coiled aneurysms treated with surgery is presented. Conclusions: aneurysms with a convenient configuration and location for either clipping or coiling might be better managed by surgical clipping in young patients considering that this treatment achieves higher rates of occlusion with a lower incidence of rebleeding. In elderly patients, each case must be discussed.

scholarly journals Clipping of previously coiled cerebral aneurysms: efficacy, safety, and predictors in a cohort of 111 patients

2016 ◽  
Vol 125 (6) ◽  
pp. 1337-1343 ◽  
Author(s):  
Badih Daou ◽  
Nohra Chalouhi ◽  
Robert M. Starke ◽  
Guilherme Barros ◽  
Lina Ya'qoub ◽  
...  
Keyword(s):  
Clinical Outcome ◽  
Cerebral Aneurysms ◽  
Endovascular Coiling ◽  
Good Clinical Outcome ◽  
Surgical Clipping ◽  
Anterior Circulation ◽  
Intraoperative Angiography ◽  
Aneurysm Size ◽  
Aneurysm Occlusion ◽  
The Mean

OBJECTIVE With the increasing number of aneurysms treated with endovascular coiling, more recurrences are being encountered. The aim of this study was to evaluate the efficacy and safety of microsurgical clipping in the treatment of recurrent, previously coiled cerebral aneurysms and to identify risk factors that can affect the outcomes of this procedure. METHODS One hundred eleven patients with recurrent aneurysms whose lesions were managed by surgical clipping between January 2002 and October 2014 were identified. The rates of aneurysm occlusion, retreatment, complications, and good clinical outcome were retrospectively determined. Univariate and multivariate logistic regressions were performed to identify factors associated with these outcomes. RESULTS The mean patient age was 50.5 years, the mean aneurysm size was 7 mm, and 97.3% of aneurysms were located in the anterior circulation. The mean follow-up was 22 months. Complete aneurysm occlusion, as assessed by intraoperative angiography, was achieved in 97.3% of aneurysms (108 of 111 patients). Among patients, 1.8% (2 of 111 patients) had a recurrence after clipping. Retreatment was required in 4.5% of patients (5 of 111) after clipping. Major complications were observed in 8% of patients and mortality in 2.7%. Ninety percent of patients had a good clinical outcome. Aneurysm size (OR 1.4, 95% CI 1.08–1.7; p = 0.009) and location in the posterior circulation were significantly associated with higher complications. All 3 patients who had coil extraction experienced a postoperative stroke. Aneurysm size (OR 1.2, 95% CI 1.02–1.45; p = 0.025) and higher number of interventions prior to clipping (OR 5.3, 95% CI 1.3–21.4; p = 0.019) were significant predictors of poor outcome. An aneurysm size > 7 mm was a significant predictor of incomplete obliteration and retreatment (p = 0.018). CONCLUSIONS Surgical clipping is safe and effective in treating recurrent, previously coiled cerebral aneurysms. Aneurysm size, location, and number of previous coiling procedures are important factors to consider in the management of these aneurysms.

scholarly journals Extracellular Vesicles Derived From Human Corneal Endothelial Cells Inhibit Proliferation of Human Corneal Endothelial Cells

2021 ◽  
Author(s):  
Mohit Parekh ◽  
Hefin Rhys ◽  
Tiago Ramos ◽  
Stefano Ferrari ◽  
Sajjad Ahmad
Keyword(s):  
Endothelial Cells ◽  
Extracellular Vesicles ◽  
Ex Vivo ◽  
Treatment Options ◽  
Proliferative Capacity ◽  
Corneal Endothelial Cells ◽  
Human Corneal Endothelial Cells ◽  
The Media

Abstract Corneal endothelial cells (CEnCs) are a monolayer of hexagonal cells that are responsible for maintaining the function and transparency of the cornea. Damage or dysfunction of CEnCs could lead to blindness. Human CEnCs (HCEnCs) have shown limited proliferative capacity in vivo hence, their maintenance is crucial. Extracellular vesicles (EVs), are responsible for inter- and intra-cellular communication, proliferation, cell-differentiation, migration, and many other complex biological processes. Therefore, we investigated the effect of EVs (derived from human corneal endothelial cell line – HCEC-12) on corneal endothelial cells. HCEC-12 cells were starved with serum-depleted media for 72 hours. The media was ultracentrifuged at 100,000xg to isolate the EVs. EV counting, characterization, internalization and localization were performed using NanoSight, flow cytometry, Dil labelling and confocal microscopy respectively. HCEC-12 and HCEnCs were cultured with media supplemented with EVs. Extracted EVs showed a homogeneous mixture of exosomes and microvesicles. Cells with EVs decreased the proliferation rate; increased apoptosis and cell size; showed poor wound healing response in vitro and on ex vivo human, porcine, and rabbit CECs. Thirteen miRNAs were found in the EV sample using next generation sequencing. We observed that increased cellular uptake of EVs by CECs limit the proliferative capacity of HCEnCs. These preliminary data may help in understanding the pathology of corneal endothelial dysfunction and provide further insights in the development of future therapeutic treatment options.

In vitro measurement of the permeability of endovascular coils deployed in cerebral aneurysms

2018 ◽  
Vol 10 (9) ◽  
pp. 896-900 ◽  
Author(s):  
Chander Sadasivan ◽  
Erica Swartwout ◽  
Ari D Kappel ◽  
Henry H Woo ◽  
David J Fiorella ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Packing Density ◽  
Cerebral Aneurysms ◽  
Wire Diameter ◽  
Endovascular Coiling ◽  
Simple Modification ◽  
Flow Through ◽  
Treatment For Cerebral Aneurysms ◽  
Endovascular Coils

Background and purposeAneurysm recurrence is the primary limitation of endovascular coiling treatment for cerebral aneurysms. Coiling is currently quantified by a volumetric porosity measure called packing density (pd). Blood flow through a coil mass depends on the permeability of the coil mass, and not just its pd. The permeability of coil masses has not yet been quantified. Here we measure coil permeability with a traditional falling-head permeameter modified to incorporate idealized aneurysms.MethodsSilicone replicas of idealized aneurysms were manufactured with three different aneurysm diameters (4, 5, and 8 mm). Four different coil types (Codman Trufill Orbit, Covidien Axium, Microvention Microplex 10, and Penumbra 400) were deployed into the aneurysms with a target pd of 35%. Coiled replicas were installed on a falling-head permeameter setup and the time taken for a column of fluid above the aneurysm to drop a certain height was recorded. Permeability of the samples was calculated based on a simple modification of the traditional permeameter equation to incorporate a spherical aneurysm.ResultsThe targeted 35% pd was achieved for all samples (35%±1%, P=0.91). Coil permeabilities were significantly different from each other (P<0.001) at constant pd. Microplex 10 coils had the lowest permeability of all coil types. Data suggest a trend of increasing permeability with thicker coil wire diameter (not statistically significant).ConclusionsA simple in vitro setup was developed to measure the permeabilities of coil masses based on traditional permeametry. Coil permeability should be considered when evaluating the hemodynamic efficacy of coiling instead of just packing density. Coils made of thicker wires may be more permeable, and thus less effective, than coils made from thinner wires. Whether aneurysm recurrence is affected by coil wire diameter or permeability needs to be confirmed with clinical trials.

Treatment of Cerebral Aneurysms—Surgical Clipping or Endovascular Coiling: The Guiding Principles

2014 ◽  
Vol 33 (05) ◽  
pp. 476-487 ◽  
Author(s):  
Ravishankar Shivashankar ◽  
Timothy Miller ◽  
Gaurav Jindal ◽  
J. Simard ◽  
E. Aldrich ◽  
...  
Keyword(s):  
Cerebral Aneurysms ◽  
Endovascular Coiling ◽  
Surgical Clipping ◽  
Guiding Principles

scholarly journals Medicare expenditures for elderly patients undergoing surgical clipping or endovascular intervention for subarachnoid hemorrhage

2017 ◽  
Vol 126 (3) ◽  
pp. 805-810 ◽  
Author(s):  
Kimon Bekelis ◽  
Daniel J. Gottlieb ◽  
Yin Su ◽  
Giuseppe Lanzino ◽  
Michael T. Lawton ◽  
...  
Keyword(s):  
Subarachnoid Hemorrhage ◽  
Elderly Patients ◽  
Instrumental Variable ◽  
Cerebral Aneurysms ◽  
Treatment Method ◽  
Cost Of Care ◽  
Endovascular Coiling ◽  
Surgical Clipping ◽  
Unmeasured Confounding ◽  
The Impact

OBJECTIVE The impact of treatment method—surgical clipping or endovascular coiling—on the cost of care for patients with aneurysmal subarachnoid hemorrhage (SAH) is debated. Here, the authors investigated the association between treatment method and long-term Medicare expenditures in elderly patients with aneurysmal SAH. METHODS The authors performed a cohort study of 100% of the Medicare fee-for-service claims data for elderly patients who had undergone treatment for ruptured cerebral aneurysms in the period from 2007 to 2012. To control for measured confounding, the authors used propensity score–adjusted multivariable regression analysis with mixed effects to account for clustering at the hospital referral region (HRR) level. An instrumental variable (regional rates of coiling) analysis was used to control for unmeasured confounding by creating pseudo-randomization on the treatment method. RESULTS During the study period, 3210 patients underwent treatment for ruptured cerebral aneurysms and met the inclusion criteria. Of these patients, 1206 (37.6%) had surgical clipping and 2004 (62.4%) had endovascular coiling. The median total Medicare expenditures in the 1st year after admission for SAH were $113,000 (IQR $77,500–$182,000) for surgical clipping and $103,000 (IQR $72,900–$159,000) for endovascular coiling. When the authors adjusted for unmeasured confounders by using an instrumental variable analysis, clipping was associated with increased 1-year Medicare expenditures by $19,577 (95% CI $4492–$34,663). CONCLUSIONS In a cohort of Medicare patients with aneurysmal SAH, after controlling for unmeasured confounding, surgical clipping was associated with increased 1-year expenditures in comparison with endovascular coiling.

Treatment of ruptured and unruptured cerebral aneurysms in the USA: a paradigm shift

2018 ◽  
Vol 10 (Suppl 1) ◽  
pp. i69-i76 ◽  
Author(s):  
Ning Lin ◽  
Kevin S Cahill ◽  
Kai U Frerichs ◽  
Robert M Friedlander ◽  
Elizabeth B Claus
Keyword(s):  
Hospital Mortality ◽  
Cerebral Aneurysms ◽  
Unruptured Aneurysm ◽  
Ruptured Aneurysm ◽  
Teaching Hospitals ◽  
Endovascular Coiling ◽  
Surgical Clipping ◽  
Unruptured Aneurysms ◽  
The Usa ◽  
Over Time

BackgroundIntegration of data from clinical trials and advancements in technology predict a change in selection for treatment of patients with cerebral aneurysm.ObjectiveTo describe patterns of use and in-hospital mortality associated with surgical and endovascular treatments of cerebral aneurysms over the past decade.Materials and methodsThe data are 34 899 hospital discharges with a diagnosis of ruptured or unruptured cerebral aneurysm from 1998 to 2007 identified from the Nationwide Inpatient Sample (NIS). The rates of endovascular coiling and surgical clipping and in-hospital mortality among patients with an aneurysm are examined over a decade by hospital and patient demographic characteristics.ResultsFrom 1998 to 2007, 20 134 discharges with a ruptured aneurysm and 14 765 discharges with an unruptured aneurysm were identified. Over this decade, the number of patients discharged with a ruptured aneurysm was stable while the number discharged with an unruptured aneurysm increased significantly. The use of endovascular coiling increased at least twofold for both groups of patient (p<0.001) with the majority of unruptured aneurysms treated with coiling by 2007. Although whites were more likely than non-whites to undergo coiling versus clipping for a ruptured aneurysm (OR=1.30; 95% CI 1.13 to 1.48) and men with unruptured aneurysms were more likely than women to undergo coiling (OR=1.26; 95% CI 1.13 to 1.40), by 2007 differences in treatment selection by gender and racial subgroups were decreased or statistically non-significant. Over time the use of coiling spread from primarily large, teaching hospitals to smaller, non-teaching hospitals.ConclusionsThe majority of unruptured aneurysms in the USA are now treated with endovascular coiling. Although surgical clipping is used for treatment of most ruptured aneurysms, its use is decreasing over time. Dissemination of endovascular procedures appears widespread across patient and hospital subgroups.

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