scholarly journals Flow-diverting stents allow efficient treatment of unruptured, intradural dissecting aneurysms of the vertebral artery: An explanatory approach using in vivo flow analysis

2015 ◽  
Vol 22 (1) ◽  
pp. 76-83 ◽  
Author(s):  
Philipp Gölitz ◽  
Tobias Struffert ◽  
Philip Hoelter ◽  
Ilker Eyüpoglu ◽  
Frauke Knossalla ◽  
...  
Keyword(s):  
Vertebral Artery ◽  
Flow Analysis ◽  
Threshold Value ◽  
Efficient Treatment ◽  
Inflow Velocity ◽  
Outflow Velocity ◽  
Aneurysm Occlusion ◽  
Occlusion Rate ◽  
Dissecting Aneurysms

Object Our study aimed to evaluate the efficiency of flow-diverting stents (FDS) in treating unruptured, intradural dissecting aneurysms of the vertebral artery (VADAs). Additionally, the effect of FDS on the aneurysmal flow pattern was investigated by performing in vivo flow analysis using parametric color coding (PCC). Methods We evaluated 11 patients with unruptured, intradural VADAs, treated with FDS. Pre- and postinterventional DSA-series were postprocessed by PCC, and time-density curves were calculated. The parameters aneurysmal inflow-velocity, outflow-velocity and relative time-to-peak (rTTP) were calculated. Pre- and postinterventional values were compared and correlated with the occlusion rate after six months. Results Follow-up DSA detected 10 aneurysms occluded, meaning an occlusion rate of 91%. No procedure-related morbidity and mortality was found. Flow analyses revealed a significant reduction of aneurysmal inflow- velocity and prolongation of rTTP after FDS deployment. Concerning aneurysm occlusion, the postinterventional outflow-velocity turned out to be a marginally statistically significant predictor. A definite threshold value (–0.7 density change/s) could be determined for the outflow-velocity that allows prediction of complete aneurysm occlusion with high sensitivity and specificity (100%). Conclusions Using FDS can be considered an efficient and safe therapy option in treating unruptured, intradural VADA. From in vivo flow analyses the postinterventional aneurysmal outflow-velocity turned out to be a potential predictor for later complete aneurysm occlusion. Here, it might be possible to determine a threshold value that allows prediction of aneurysm occlusion with high specificity and sensitivity. As fast, applicable and easy-to-handle tool, PCC could be used for procedural monitoring and might contribute to further treatment optimization.

Combined endovascular treatment of dissecting vertebral artery aneurysms by using stents and coils

2001 ◽  
Vol 94 (3) ◽  
pp. 427-432 ◽  
Author(s):  
Pedro Lylyk ◽  
José E. Cohen ◽  
Rosana Ceratto ◽  
Angel Ferrario ◽  
Carlos Miranda
Keyword(s):  
Vertebral Artery ◽  
Neurological Complication ◽  
Safe Alternative ◽  
Endovascular Stents ◽  
Content Type ◽  
Aneurysm Occlusion ◽  
Intravascular Stent ◽  
Dissecting Aneurysms ◽  
Fine Print

Object. With the recent development and refinement of endovascular stents, the significant potential for these devices in the treatment of wide-necked dissecting and fusiform aneurysms has become apparent. In this article the authors report on the use of stents and coils to treat dissecting and fusiform vertebral artery (VA) aneurysms. Methods. Eight consecutive patients harboring eight dissecting aneurysms and one fusiform aneurysm of the VA were succesfully treated using a procedure in which the authors inserted an intravascular stent and secondary endosaccular coils when needed. In all but one patient complete aneurysm occlusion was achieved, and in all cases there was no neurological complication. Follow-up angiography examinations were performed in all patients (mean duration of follow-up angiography review 13.1 months, range 3–42 months). The patients remained stable throughout the clinical follow-up period (mean 14.1 months, range 4–42 months). No rebleeding was recorded. Conclusions. At present this combined approach represents a reliable and safe alternative for the treatment of VA dissecting aneurysms, especially in patients who cannot tolerate occlusion tests.

Endovascular reconstruction of unruptured intradural vertebral artery dissecting aneurysms with the Pipeline embolization device

2015 ◽  
Vol 8 (10) ◽  
pp. 1048-1051 ◽  
Author(s):  
Anna Luisa Kühn ◽  
Peter Kan ◽  
Francesco Massari ◽  
J Diego Lozano ◽  
Samuel Y Hou ◽  
...  
Keyword(s):  
Vertebral Artery ◽  
Thromboembolic Complication ◽  
Parent Artery ◽  
Pipeline Embolization Device ◽  
Complete Occlusion ◽  
Scale Scores ◽  
Major Procedure ◽  
Aneurysm Occlusion ◽  
Dissecting Aneurysms

BackgroundDissecting aneurysms of the vertebral artery (VA) are difficult to treat using current surgical and endovascular techniques.ObjectiveTo analyze retrospectively the efficacy and safety of flow diverters in the treatment of dissecting aneurysms of the vertebral artery.MethodsWe identified six patients with six unruptured VA dissecting aneurysms either arising from the V4 or V3–V4 junction that were treated with the Pipeline embolization device (PED) at our institution between July 2012 and February 2015. Among other parameters, technical feasibility of the procedure, procedure-related complications, angiographic results, and clinical outcome were evaluated.ResultsPED placement was achieved in all cases and immediate angiography follow-up demonstrated intra-aneurysmal contrast stasis with parent artery preservation. A temporary episode of dysarthria was noted in one patient. Major procedure-related complications were not observed. The 6-month follow-up (n=6) demonstrated complete/near-complete aneurysm obliteration in five patients and partial obliteration in one. At the 1-year follow-up (n=5) stable complete aneurysm occlusion was seen in two patients. Two cases showed progression from near complete occlusion and partial occlusion at 6 months to complete occlusion and near complete occlusion. One cases showed unchanged near complete occlusion. No aneurysmal bleeding, in-stent stenosis or thromboembolic complication was seen. National Institutes of Health Stroke Scale and modified Rankin scale scores remained unchanged from admission to discharge.ConclusionsOur preliminary experience with the use of PED for the treatment of intradural VA dissecting aneurysms shows promising short-term results, making this technique a feasible and safe treatment option in patients suitable for this approach. However, long-term and larger cohort studies are needed to validate these results.

Factors Influencing Leukocyte Adherence in Microvessels

1977 ◽  
Vol 38 (04) ◽  
pp. 0823-0830 ◽  
Author(s):  
Mayrovttz N. Harvey ◽  
Wiedeman P. Mary ◽  
Ronald F. Tuma
Keyword(s):  
Blood Flow ◽  
Shear Stress ◽  
Tissue Injury ◽  
Threshold Value ◽  
In Vivo Studies ◽  
Leukocyte Adherence ◽  
Rolling Velocity ◽  
Subsequent Behavior ◽  
Flow Stasis

SummaryIn vivo studies of the microcirculation of an untraumatized and unanesthetized animal preparation has shown that leukocyte adherence to vascular endothelium is an extremely rare occurrence. Induction of leukocyte adherence can be produced in a variety of ways including direct trauma to the vessels, remote tissue injury via laser irradiation, and denuding the epithelium overlying the observed vessels. The role of blood flow and local hemodynamics on the leukocyte adherence process is quite complex and still not fully understood. From the results reported it may be concluded that blood flow stasis will not produce leukocyte adherence but will augment pre-existing adherence. Studies using 2 quantitative measures of adherence, leukocyte flux and leukocyte velocity have shown these parameters to be affected differently by local hemodynamics. Initial adherence appears to be critically dependent on the magnitude of the blood shear stress at the vessel wall as evidenced by the lack of observable leukocyte flux above some threshold value. Subsequent behavior of the leukocytes as characterized by their average rolling velocity shows no apparent relationship to shear stress but, for low velocities, may be related to the linear blood velocity.

LVIS-within-enterprise double-stent procedure without coiling beneficial as treatment of unruptured vertebral artery dissecting aneurysms

2021 ◽  
pp. 159101992110251
Author(s):  
Hyun Ho Choi ◽  
Young Dae Cho ◽  
Dong Hyun Yoo ◽  
Hyun-Seung Kang ◽  
Moon Hee Han
Keyword(s):  
Vertebral Artery ◽  
Clinical Outcomes ◽  
Local Anesthesia ◽  
Thrombus Formation ◽  
Flow Diversion ◽  
Fusiform Aneurysm ◽  
Stent Deployment ◽  
Double Stent ◽  
Dissecting Aneurysms

Stenting of vertebral artery dissecting aneurysms (VADAs) may promote mural apposition of intimal flaps, preserving the patency of injured vessels. Moreover, stent deployment may serve to alter intra-aneurysm flow, inducing saccular thrombus formation, neointimal development, and remodeling of injured vessels. Although an overlapping multistent strategy with coiling has proven successful in this setting, yielding good anatomic and clinical outcomes, coiling may be technically infeasible in some VADAs with unfavorably configured circumferential elevations. Herein, we describe three patients with VADAs for whom coiling was deemed technically problematic. Each underwent double stenting (LVIS within Enterprise), without coil insertion, using local anesthesia. Conventional angiographic follow-up regularly disclosed excellent saccular occlusion and subsequent remodeling of stented arteries. LVIS-within-Enterprise double stenting may be of particular benefit in patients with VADAs, the Enterprise providing outer support to minimize stent bulging (as a fusiform aneurysm) as the inner LVIS reinforces flow diversion.

scholarly journals Imaging-Guided Therapy Simultaneously Targeting HER2 and EpCAM with Trastuzumab and EpCAM-Directed Toxin Provides Additive Effect in Ovarian Cancer Model

Cancers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 3939
Author(s):  
Tianqi Xu ◽  
Anzhelika Vorobyeva ◽  
Alexey Schulga ◽  
Elena Konovalova ◽  
Olga Vorontsova ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Growth Factor Receptor ◽  
Repeated Administration ◽  
Ovarian Cancer Cells ◽  
Her2 Positive ◽  
Efficient Treatment ◽  
Pseudomonas Exotoxin A ◽  
Epidermal Growth

Efficient treatment of disseminated ovarian cancer (OC) is challenging due to its heterogeneity and chemoresistance. Overexpression of human epidermal growth factor receptor 2 (HER2) and epithelial cell adhesion molecule (EpCAM) in approx. 30% and 70% of ovarian cancers, respectively, allows for co-targeted treatment. The clinical efficacy of the monoclonal antibody trastuzumab in patients with HER2-positive breast, gastric and gastroesophageal cancers makes it readily available as the HER2-targeting component. As the EpCAM-targeting component, we investigated the designed ankyrin repeat protein (DARPin) Ec1 fused to a truncated variant of Pseudomonas exotoxin A with reduced immunogenicity and low general toxicity (LoPE). Ec1-LoPE was radiolabeled, evaluated in ovarian cancer cells in vitro and its biodistribution and tumor-targeting properties were studied in vivo. The therapeutic efficacy of Ec1-LoPE alone and in combination with trastuzumab was studied in mice bearing EpCAM- and HER2-expressing SKOV3 xenografts. SPECT/CT imaging enabled visualization of EpCAM and HER2 expression in the tumors. Co-treatment using Ec1-LoPE and trastuzumab was more effective at reducing tumor growth and prolonged the median survival of mice compared with mice in the control and monotherapy groups. Repeated administration of Ec1-LoPE was well tolerated without signs of hepatic or kidney toxicity. Co-treatment with trastuzumab and Ec1-LoPE might be a potential therapeutic strategy for HER2- and EpCAM-positive OC.

Differential regulation of insulin resistance and hypertension by sex hormones in fructose-fed male rats

2005 ◽  
Vol 289 (4) ◽  
pp. H1335-H1342 ◽  
Author(s):  
Harish Vasudevan ◽  
Hong Xiang ◽  
John H. McNeill
Keyword(s):  
Insulin Resistance ◽  
Blood Pressure ◽  
Insulin Sensitivity ◽  
Sex Hormones ◽  
Threshold Value ◽  
Relative Increase ◽  
Estrogen Treatment ◽  
Male Rats ◽  
Normal Chow

Differences in gender are in part responsible for the development of insulin resistance (IR) and associated hypertension. Currently, it is unclear whether these differences are dictated by gender itself or by the relative changes in plasma estrogen and/or testosterone. We investigated the interrelationships between testosterone and estrogen in the progression of IR and hypertension in vivo in intact and gonadectomized fructose-fed male rats. Treatment with estrogen significantly reduced the testosterone levels in both normal chow-fed and fructose-fed rats. Interestingly, fructose feeding induced a relative increase in estradiol levels, which did not affect IR in both intact and gonadectomized fructose-fed rats. However, increasing the estrogen levels improved insulin sensitivity in both intact and gonadectomized fructose-fed rats. In intact males, fructose feeding increased the blood pressure (140 ± 2 mmHg), which was prevented by estrogen treatment. However, the blood pressure in the fructose-fed estrogen rats (125 ± 1 mmHg) was significantly higher than that of normal chow-fed (113 ± 1 mmHg) and fructose-fed gonadectomized rats. Estrogen treatment did not affect the blood pressure in gonadectomized fructose-fed rats (105 ± 2 mmHg). These data suggest the existence of a threshold value for estrogen below which insulin sensitivity is unaffected. The development of hypertension in this model is dictated solely by the presence or absence of testosterone. In summary, the development of IR and hypertension is governed not by gender per se but by the interactions of specific sex hormones such as estrogen and testosterone.

scholarly journals One-stage Stent-assisted Coil Embolization for Rupture-side-unknown Bilateral Vertebral Artery Dissecting Aneurysms in an Acute Stage: A Case Report

2018 ◽  
Vol 5 (2) ◽  
pp. 45-49
Author(s):  
Mio Terashima ◽  
Yoichi Miura ◽  
Fujimaro Ishida ◽  
Naoki Toma ◽  
Tomohiro Araki ◽  
...  
Keyword(s):  
Case Report ◽  
Vertebral Artery ◽  
Coil Embolization ◽  
Acute Stage ◽  
One Stage ◽  
Dissecting Aneurysms

Treatment of Dissecting Distal Vertebral Artery (V4) Aneurysms With Flow Diverters

2017 ◽  
Vol 15 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Jacquelyn A Corley ◽  
Ali Zomorodi ◽  
L Fernando Gonzalez
Keyword(s):  
Vertebral Artery ◽  
Neurological Deficits ◽  
Medication Regimen ◽  
Antiplatelet Medication ◽  
Average Improvement ◽  
Multiple Challenges ◽  
Partial Thrombosis ◽  
Flow Diverters ◽  
Dissecting Aneurysms

Abstract BACKGROUND Dissecting aneurysms of the intracranial vertebral arteries are rare; however, treatment of these presents multiple challenges, including high risk of rebleeding, development of thromboembolic strokes, and progressive partial thrombosis. Flow diverters, such as Pipeline Endovascular Devices (PEDs; Covidien, Medtronic Inc, Dublin, Ireland), have emerged as a potential treatment option. OBJECTIVE To present our experience with patients treated at our institution with PEDs for dissecting distal vertebral artery (V4 segment) aneurysms. METHODS A retrospective search of our prospectively maintained database was performed between January 2014 and December 2016. We queried our database for all patients treated with PED for dissecting aneurysms of the V4 segment. Information was gathered including demographics, the location and morphology of the aneurysm, the clinical presentation, specific form of treatment, complications, antiplatelet medication regimen, and follow-up time. RESULTS There were a total of 9 patients with dissecting V4 aneurysms treated with PED during the study period. All were treated initially with an average of 1.2 PEDs. All patients were followed with at least one repeat diagnostic angiogram and there was no residual aneurysm seen in 8 of 9 cases. In those that presented with neurological deficits, there was an average improvement in modified Rankin Scale of 2.85 points. CONCLUSION PED is a safe and effective tool that can be used to treat ruptured dissecting aneurysms of this specific segment of the posterior circulation, but it does require close management of antiplatelet therapy in the setting of subarachnoid hemorrhage and close angiographic follow-up.

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