In six, healthy, adult horses, the origin of the left internal carotid artery was isolated via a modified hyovertebrotomy approach. Normograde blood flow was occluded by placement of a tourniquet on the artery near its origin. Lumenal access was gained through placement of a distally directed introducer sheath and retrograde blood flow from the cerebral arterial circle was confirmed. An 8.5 mm diameter detachable latex balloon loaded onto a carrier catheter and placed within a guiding catheter was introduced into the internal carotid artery through the introducer sheath and advanced to the target occlusion site (the proximal curve of the sigmoid flexure of the internal carotid artery). The balloon was inflated with 0.5 ml of a radiopaque solution. Correct placement and inflation of the balloon were confirmed by intraoperative radiography. The balloon was then released and the guiding and carrier catheters withdrawn. Immediate embolization of the distal internal carotid artery was determined by lack of retrograde blood flow through the introducer sheath. The introducer sheath was withdrawn from the vessel and the proximal tourniquet was replaced with two ligatures. Horses were euthanized on day 30 and detailed gross and histopathologic examinations were performed. The balloons were easily placed into the target site and produced immediate occlusion of retrograde flow from the cerebral arterial circle. All balloons remained inflated in their original position throughout the study period. Mature thrombus formation and absence of clinically significant inflammation were consistent findings in all occluded internal carotid arteries at gross necropsy and histologic examination. / Master of Science

No description available.

L’embolisation occupe une part croissante de l’activité de la radiologie interventionnelle endovasculaire. Les agents d’embolisation sont nombreux, présentent des propriétés variables et permettent d’obtenir une hémostase, un hémodétournement ou réaliser le vecteur d’une thérapie ciblée. Notre travail se décompose en trois parties visant successivement à un état de l'art des agents d’embolisation disponibles, puis des travaux originaux de laboratoire, et enfin l’analyse rétrospective de diverses études radio-cliniques constituées dans notre centre. La première partie basée sur une analyse de la littérature constitue un chapitre introductif dans lequel sont évalués les caractéristiques techniques, les avantages et limites des agents d’embolisation utilisés en pratique clinique courante. Le deuxième volet repose sur des travaux fondamentaux sur l’animal réalisés dans le laboratoire de cathétérisme expérimental de l’ISIT (Professeurs Boyer et Lusson) à la faculté de Médecine de Clermont-Ferrand, et dans le laboratoire des biomatériaux endovasculaires de l’université de Montréal (Professeur Lerouge et Soulez). Dans une première série d’expérimentation nous avons participé à Montréal au développement d’un agent d’embolisation qui combine les avantages d’un gel (solidification au contact du sang) et d’un sclérosant (destruction des cellules endothéliales). Le gel ainsi mis au point a fait l’objet d’un dépôt de brevet. Il pourrait permettre de prévenir et/ou traiter les fuites observées dans le traitement par endoprothèse des anévrysmes de l’aorte. Dans un deuxième protocole expérimental nous avons analysé à Clermont-Ferrand l’interaction entre agent d’embolisation et chimiothérapie en étudiant les modifications pharmacocinétiques observées en fonction de la voie d’administration et de l’association à une embolisation partielle ou complète de l’artère hépatique sur un modèle porcin. Le troisième volet repose sur des travaux cliniques originaux analysant rétrospectivement divers points sensibles en embolisation parenchymateuse. Cette partie s’appuie sur des collaborations multidisciplinaires fortes en pathologies gynécologiques, urologiques, hépatiques et spléniques. Il faut signaler enfin, la parution prévue pour le premier trimestre 2012 de l'ouvrage "Embolisation" (350 pages, Springer Ed., P. Chabrot et L. Boyer). Une version anglaise de ce livre suivra courant 2012. / Embolization is an increasing part of the activity of endovascular interventional radiology. Embolization agents are numerous, have variable properties and make it possible to obtain a hemostasis, a hemodiversion, or achieve the vector of a targeted therapy. Our work is divided into three parts, successively aimed at a state of the art of available embolization agents, then original laboratory work, and finally the retrospective analysis of various radio-clinical studies made in our research center. The first part based on an analysis of the literature constitutes an introductory chapter in which the technical characteristics, the advantages and the limits of the embolization agents used in current clinical practice are assessed. The second part is based on fundamental animal studies carried out in the experimental catheterization laboratory of ISIT (Professors Boyer and Lusson) at the Faculty of Medicine of Clermont-Ferrand, and in the laboratory of endovascular biomaterials of the university. of Montreal (Professor Lerouge and Soulez). In a first series of experiments, in Montreal, we participated in the development of an embolization agent that combines the advantages of a gel (solidification in contact with blood) and a sclerosant (destruction of endothelial cells). The gel thus developed has been the subject of a patent application. It may be able to prevent and / or treat the leaks observed in stent-graft treatment of aortic aneurysms. In a second experimental protocol, in Clermont-Ferrand, we analyzed the interaction between embolization agent and chemotherapy by studying the pharmacokinetic changes observed according to the route of administration and the association with partial or complete embolization of the hepatic artery on a porcine model. The third part is based on original clinical work analyzing retrospectively various sensitive points in parenchymal embolization. This part is based on strong multidisciplinary collaborations in gynecological, urological, hepatic and splenic pathologies. Finally, it is necessary to announce the publication scheduled for the first quarter of 2012 of the book "Embolisation" (350 pages, Springer Ed., P. Chabrot and L. Boyer). An English version of this book will follow in the course of 2012.

No description available.

No description available.

The purpose of this study is to determine features of uterine leiomyoma on Magnetic Resonance Imaging (MRI) that identify predictors of response to Uterine Arterial Embolization (UAE). MRI images were obtained before and after UAE in 35 women. These images were analyzed for uterine and fibroid size changes along with fibroid border characteristics and location for a total of 73 fibroids. Fibroids were classified as either smooth or lobulated based on border appearance on MR imaging to determine any differences in mean fibroid volume reduction post-embolization. The mean decrease in fibroid volume from pre-embolization to post-embolization was 48.1% ± 28.6 % (SD) (P < 0.001). No statistical difference was detected in the mean volume reduction between lobulated and smooth fibroids, 40.6% ± 23.1% (SD) and 50.9% ± 30.2% (SD) respectively, with a confidence interval [-25.1, 4.6, SEM 7.5, Df 71], single factor ANOVA (F[1,71]=1.88, Fcrit=3.98, p=0.17). However, some difference was detected in the failure rate of lobulated versus smooth fibroids to embolization, 5% and 9.4% respectively, ANOVA (F [1, 71]= 0.37, Fcrit= 3.98, p > 0.1), albeit at low statistical power. Also no difference was detected in mean fibroid volume reduction between intramural, submucosal, and subserosal fibroids. Thus, we introduced a novel characteristic by which to classify uterine fibroids based upon border appearance on MR imaging.

No presenta resumen. / Revisión por pares

Thesis (doctoral)--University of Lund, 1981. / Includes bibliographical references.

Abstract The purpose of the study was to analyze the angiographic and clinical results of endovascularly treated intracranial aneurysms in Oulu University Hospital, Finland. The study population consisted of 416 consecutive patients (467 aneurysms, 332 ruptured), who were referred for endovascular treatment of intracranial aneurysm(s) between December 1993 and July 2004. Technical failures were analyzed for an assesment of technical feasibility. Angiographic results were assessed using modified Raymond Classification. Clinical results were analyzed from patient files using the Glasgow Outcome Scale (GOS). Patient, aneurysm, and procedure related variables were tested with an intention to find the predictors of the angiographic and clinical outcome. The clinical effects on presenting symptoms were analyzed for a subgroup of patients with a symptomatic unruptured aneurysm (n = 30). The mean results on technical feasibility, complications, and angiographic results were separately assessed for three time periods (1993–1997, 1998–2000 and 2001–2004) to demonstrate potential significant changes in outcome. Endovascular treatment of saccular aneurysms was technically feasible in 91.4% of the treatments. Initially, 25.7% of the aneurysms were completely occluded, 57.9% had a neck remnant, and 16.3% remained incompletely occluded. In follow-up, the rates for complete occlusions, neck remnants and incomplete occlusions were 37.6%, 49.7% and 12.7%, respectively. Small aneurysm size predicted complete aneurysm occlusion, while a wide aneurysm neck and location in the posterior circulation predicted incomplete occlusion. In follow-up (mean 38.2 months), 78.1% of the patients with a ruptured aneurysm and 92.3% of the patients with an unruptured aneurysm had resumed independent life (GOS 4-5). The predictors of good outcome were young age, good preprocedural clinical condition, small amount of blood in CT scan, and uncomplicated procedure. Ten of the treated aneurysms involved intracranial bleeding in follow-up, and the annual risk for bleeding after endovascular treatment was 0.95% among the patients with ruptured aneurysms and 0.33% among those with unruptured aneurysms. The risk of bleeding was associated with larger aneurysm size and lower occlusion grade. In the subgroup of symptomatic unruptured aneurysms, 53.4% of the patients showed either resolution or improvement of the symptoms after treatment. The rates of procedural complications, morbidity, and mortality were 16.5%, 6.7%, and 1.7%, respectively. The risk for procedural complications was higher when the balloon remodeling technique was used and lower in retreatments. Technical feasibility (85.6%, 90.6%, and 95.7%, respectively) and the percentage of complete occlusions (initially 16.5%, 23.0%, and 32.9%, respectively) were significantly improved by increased experience, while no statistical difference was detected in the total procedural complication rates (15.4%, 15.7%, and 18.3%, respectively) or the combined procedural morbidity and mortality rates (8.0%, 8.3%, and 9.1%, respectively). All six dissecting aneurysms treated with parent artery occlusion or the stent remodeling technique resulted in complete occlusions. The present results confirmed endovascular treatment of intracranial aneurysms as a feasible, safe, and effective method in preventing further bleeding of aneurysms. Increased experience in a single center improved the feasibility of the treatment as well as the angiographic results.

Stomal varices are a rare phenomenon that can infrequently develop in patients with enterostomies and portal hypertension. Acute gastrointestinal bleeding from stomal varices can be life threatening and is often a diagnostic challenge. We present a case of severe gastrointestinal hemorrhage from stomal varices requiring emergent intervention with transjugular intrahepatic portosystemic shunt (TIPS) and plug embolization. A 61 year old male patient with a history of colorectal adenocarcinoma status post chemotherapy, radiation, along with low anterior colon resection with ostomy creation presented with a one day history of sudden onset of bright red blood from his colostomy site. He had a known history of decompensated cirrhosis related to hepatitis C and alcohol abuse. On arrival, the patient was tachycardic with borderline low blood pressure with evidence of bright red bleeding from his ostomy site. After initial resuscitation, a colonoscopy through the stoma revealed active bleeding from what appeared to be submucosal colonic varices. The patient continued to experience large volumes of blood loss and became more hemodynamically unstable. Cross sectional imaging showed colonic varices being fed by a branch of the inferior mesenteric vein. The patient underwent TIPS followed by Amplatzer plug embolization of the branch of the interior mesenteric vein that was feeding the colonic stomal varices. The patient’s bleeding was stopped by the combination of these therapeutic modalities and he recovered without complication. The current standard of care for treatment of such varices is with either (1) local therapy with ligation or sclerotherapy, (2) surgical interventions such as stomal manipulation or vessel shunting, either transhepatic or portosystemic to reduce portal pressures, or (3) liver transplantation. Our patient required an unusual combination of TIPS and Amplatzer plug embolization to control his massive hemorrhage. This combination of therapies has been shown effective for the management of select cases of esophageal or gastric variceal bleeding; however, our case demonstrates that the application of the TIPS plus Amplatzer plug embolization can be applied more broadly to the rare scenario of colonic stomal varices.