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Durale Sinus cavernosus FistelnBenndorf, Götz 15 July 2002 (has links)
Die durale Fistel des Sinus cavernosus (DSCF) ist eine seltene Erkrankung, die durch kleine abnorme arteriovenöse Verbindungen zwischen A. carotis interna bzw. externa und dem Sinus cavernosus gekennzeichnet ist. Bei nicht entsprechender Diagnostik kann es zu Verschleppung der Diagnose und erheblicher Beeinträchtigung der Patienten bis zum vollständigen Visusverlust kommen. Aus diesem Grund ist die rechzeitige Erkennung der Erkrankung wichtig und für eine effektive therapeutische Maßnahme von Bedeutung. MRT und CT können Anhaltspunkte für eine Verdachtsdiagnose liefern und spielen eine wesentliche Rolle bei der Suche nach intrakraniellen Blutungen oder Infarzierungen. Zum sicheren Ausschluß von insbesondere kleineren Fisteln und mehr noch zur genaueren Therapieplanung ist jedoch die intraarterielle DSA nach wie vor unerlässlich, vor allem um Verwechslungen mit anderen Erkrankungen, wie z. B. endokrine Orbitopathie oder Myositis, zu vermeiden. Die Behandlung der DSCF besteht heute vor allem in der Anwendung endovaskulärer Techniken. In der vorliegenden Studie wurden 26 von insgesamt 29 Patienten durch diese Technik behandelt und bei allen ein vollständiger Verschluß erzielt (100%; angiographische Verlaufskontrolle bei 22 Patienten). Die Rate der klinischen Heilung insgesamt betrug 96%, bei einer Komplikationsrate von 3% für ein transientes neurologisches Defizit (Abduzensparese bei einer Patientin). Die endovaskuläre Behandlung von DSCF durch transvenöse Embolisation durch einen erfahrenen Spezialisten stellt heute aufgrund ihrer hohen Effektivität und niedrigen Komplikationsrate die Methode der Wahl dar. Hierbei sind gesteuert ablösbare Platincoils das zu bevorzugende Embolisat. Der Einsatz aggressiver Behandlungsmethoden, insbesondere mikrochirurgischer Techniken bei sogenannten "nicht embolisierbaren Fisteln", hat damit seine Berechtigung weitgehend verloren. / The dural fistula of the cavernous sinus (DCSF) is a rare disease, characterized by abnormal arteriovenous communication between the internal or external carotid artery and the cavernous sinus. Inadequate diagnostic procedures may delay the correct diagnosis as well as the appropriate therapeutic management with deterioration of the patient's symptoms and possible visual loss. Therefore, early recognition of the disease is important for effective therapeutic management. MRI and CT may be helpful in leading to the diagnosis and play an important role in excluding intracranial hemorrhage or infarction. For definite diagnosis, in particular of small low-flow fistulas and to avoid misdiagnosis such as endocrine orbitopathy or myositis as well as for therapeutic planning, intraarterial DSA is still mandatory. Therapeutic management of DCSFs today consists mainly in performing endovascular techniques. In the here presented study, 26 of 29 patients were treated using transvenous embolization. Complete occlusion was achieved in 100% (angiographic follow-up available in 22 patients). Clinical cure was achieved in 96%. The complication rate was 3% for transient neurological deficit (6th nerve palsy in one patient). Because of its high success rate and the low complication rate, endovascular treatment of DCSF using transvenous embolization by an experienced operator represents today the method of choice. Detachable platinum coils is the preferable embolic agent. More aggressive methods, in particular microsurgical techniques in cases of so-called "intractable fistulas" should no longer be used.
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Tratamento das pacientes sintomáticas portadoras de miomas uterinos através da associação das técnicas de embolização dos miomas e ligadura endovascular das artérias uterinas / Uterine artery embolization with polyvinyl-alcohol particles and metallic coils for the treatment of symptomatic patients with fibroidsRicardo Augusto de Paula Pinto 27 March 2007 (has links)
Os miomas uterinos são os tumores benignos mais comuns do trato genital feminino, sendo que nas mulheres portadoras, 30% são sintomáticos e exigem alguma forma de tratamento. No presente estudo, foram tratadas 35 pacientes sintomáticas com diagnóstico clínico e ultra-sonográfico de mioma uterino, por meio da embolização dos miomas com partículas de polivinil-álcool associadas à obstrução das artérias uterinas com micromolas fibradas. A avaliação clínica e ecográfica foram inicialmente feitas e o acompanhamento realizado após um, três, seis e doze meses do procedimento. O sucesso técnico foi de 94,3%. O volume uterino médio era de 404,53 cm3 antes do tratamento endovascular percutâneo e o sintoma mais freqüente, em 82,9%, a menorragia. A redução média dos volumes uterinos foi de 21,4%, 39,7%, 53,8% e 59,8% respectivamente em um, três, seis e 12 meses (p < 0,01). Houve, também, a redução do volume do nódulo miomatoso dominante em 5%, 18,5%, 26,8% e 32,9% em um, três, seis e 12 meses, respectivamente (p < 0,01). A melhora e o controle da menorragia foram obtidos em 100% das pacientes tratadas. Houve necessidade de histerectomia em uma paciente por insucesso no controle da dor após seis meses do procedimento. A embolização dos miomas uterinos com partículas de polivinil-álcool associada à oclusão endovascular das artérias uterinas com micromolas fibradas é uma alternativa de tratamento minimamente invasivo para as pacientes sintomáticas portadoras de miomas uterinos que proporciona controle e melhora dos sintomas e redução do tamanho dos miomas e do volume uterino. / Uterine fibroids are the most frequent benign tumors of the female genital tract. The tumors are symptomatic in about 30% of the cases, requiring medical treatment. In the present study, a total of 35 clinically symptomatic patients with ultrasonographic diagnosis of fibroids underwent endovascular treatment, which consisted of embolization of the uterine arteries with 355-500 micras PVA particles associated to metallic coils. Clinical and ultrasonographic evaluations were performed at baseline, 1, 3, 6 and 12 months post-intervention. Technical success was obtained in 94.3% of the cases. Mean uterine volume before the procedure was 404.53 cm³ and menorrhagia was the most frequent symptom (82.9%). Mean reduction of the uterine volumes was 21.4%, 39.7%, 53.8% and 59.8% respectively at 1, 3, 6 and 12 months post-intervention. Dominant fibroid size was also significantly reduced after the procedure (5%, 18.5%, 26.8% and 32.9% reductions at 1, 3, 6 and 12 months, respectively; p < 0.01). Vaginal bleeding was abolished in all cases after the 12-month follow up. One patient needed to undergo hysterectomy 6 months after the procedure due to uncontrolled pain. Our results demonstrate uterine arteries embolization is minimally invasive and provides clinical control of the fibroids associated to significant reduction of the uterine volume. Moreover, the technique preserves the uterus and should be considered a therapeutic alternative to standard surgical treatment.
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Tratamento das pacientes sintomáticas portadoras de miomas uterinos através da associação das técnicas de embolização dos miomas e ligadura endovascular das artérias uterinas / Uterine artery embolization with polyvinyl-alcohol particles and metallic coils for the treatment of symptomatic patients with fibroidsPinto, Ricardo Augusto de Paula 27 March 2007 (has links)
Os miomas uterinos são os tumores benignos mais comuns do trato genital feminino, sendo que nas mulheres portadoras, 30% são sintomáticos e exigem alguma forma de tratamento. No presente estudo, foram tratadas 35 pacientes sintomáticas com diagnóstico clínico e ultra-sonográfico de mioma uterino, por meio da embolização dos miomas com partículas de polivinil-álcool associadas à obstrução das artérias uterinas com micromolas fibradas. A avaliação clínica e ecográfica foram inicialmente feitas e o acompanhamento realizado após um, três, seis e doze meses do procedimento. O sucesso técnico foi de 94,3%. O volume uterino médio era de 404,53 cm3 antes do tratamento endovascular percutâneo e o sintoma mais freqüente, em 82,9%, a menorragia. A redução média dos volumes uterinos foi de 21,4%, 39,7%, 53,8% e 59,8% respectivamente em um, três, seis e 12 meses (p < 0,01). Houve, também, a redução do volume do nódulo miomatoso dominante em 5%, 18,5%, 26,8% e 32,9% em um, três, seis e 12 meses, respectivamente (p < 0,01). A melhora e o controle da menorragia foram obtidos em 100% das pacientes tratadas. Houve necessidade de histerectomia em uma paciente por insucesso no controle da dor após seis meses do procedimento. A embolização dos miomas uterinos com partículas de polivinil-álcool associada à oclusão endovascular das artérias uterinas com micromolas fibradas é uma alternativa de tratamento minimamente invasivo para as pacientes sintomáticas portadoras de miomas uterinos que proporciona controle e melhora dos sintomas e redução do tamanho dos miomas e do volume uterino. / Uterine fibroids are the most frequent benign tumors of the female genital tract. The tumors are symptomatic in about 30% of the cases, requiring medical treatment. In the present study, a total of 35 clinically symptomatic patients with ultrasonographic diagnosis of fibroids underwent endovascular treatment, which consisted of embolization of the uterine arteries with 355-500 micras PVA particles associated to metallic coils. Clinical and ultrasonographic evaluations were performed at baseline, 1, 3, 6 and 12 months post-intervention. Technical success was obtained in 94.3% of the cases. Mean uterine volume before the procedure was 404.53 cm³ and menorrhagia was the most frequent symptom (82.9%). Mean reduction of the uterine volumes was 21.4%, 39.7%, 53.8% and 59.8% respectively at 1, 3, 6 and 12 months post-intervention. Dominant fibroid size was also significantly reduced after the procedure (5%, 18.5%, 26.8% and 32.9% reductions at 1, 3, 6 and 12 months, respectively; p < 0.01). Vaginal bleeding was abolished in all cases after the 12-month follow up. One patient needed to undergo hysterectomy 6 months after the procedure due to uncontrolled pain. Our results demonstrate uterine arteries embolization is minimally invasive and provides clinical control of the fibroids associated to significant reduction of the uterine volume. Moreover, the technique preserves the uterus and should be considered a therapeutic alternative to standard surgical treatment.
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Avaliação da expressão gênica relacionada à receptividade endometrial em pacientes submetidos à embolização do mioma uterino / Evaluation of gene expression related to endometrial receptivity in patients undergoing uterine leiomyoma embolizationHilário, Sandro Garcia 29 May 2012 (has links)
OBJETIVO: Avaliar a receptividade endometrial de pacientes submetidas à embolização do mioma uterino, analisando a expressão gênica de LIF, IL-11, IL-6, claudina-4, HoxA-10, HoxA-11, receptor de estrogênio e receptor de progesterona antes e após este procedimento. CASUÍSTICA E MÉTODOS: Foram colhidas biópsias aspirativas de endométrio de 30 pacientes previamente à embolização do mioma uterino e repetida a coleta 3 a 4 meses após este procedimento. A média etária do grupo estudado foi de 36,2 anos. O volume uterino médio pré-embolização foi de 662,1 cc e o pós-embolização foi de 338,2 cc, medidos através de ressonância nuclear magnética. INTERVENÇÃO: As amostras de endométrio foram analisadas pela técnica de RT-PCR para os genes LIF, IL-11, IL-6, claudina-4, HoxA-10, HoxA-11, receptor de estrogênio e receptor de progesterona. RESULTADOS: Dentre os genes estudados, LIF (p=0,005), IL-11 (p=0,001) e HoxA-11 (p=0,021) apresentaram redução estatisticamente significante da expressão no endométrio após a embolização. Os demais genes não apresentaram alteração da expressão estatisticamente significante. CONCLUSÃO: Houve alteração da expressão de genes relacionados à receptividade endometrial, no endométrio de pacientes tratadas pela técnica da embolização do mioma uterino / OBJECTIVE: Assessing endometrial receptivity in patients undergoing uterine fibroid embolization by analyzing the gene expression of LIF, IL-11, IL-6, claudin-4, Hoxa-10, Hoxa-11, estrogen receptor and progesterone receptor before and after this procedure. METHODS: Endometrial aspiration biopsies were collected from 30 patients prior to embolization of uterine myoma, and the collections were repeated 3 to 4 months after this procedure. The average age of the study group was 36.2 years old. The mean uterine volume pre-embolization was 662. 1 cc and post-embolization was 338.2cc as measured by Magnectic Resonance Imaging (MRI). INTERVENTION: Endometrial samples were analyzed by RT-PCR for genes LIF, IL-11, IL-6, claudin-4, Hoxa-10, Hoxa-11, estrogen receptor and progesterone receptor. RESULTS: Among the studied genes, LIF (p=0.005), IL-11 (p=0.001) and Hoxa-11 (p=0.021) showed statistically significant reduction of expression in the endometrium after embolization. The remaining genes showed no statistically significant change in expression. CONCLUSION: There was altered expression of genes related to endometrial receptivity in the endometrium of patients treated by the technique of embolization of uterine myoma
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Avaliação da expressão gênica relacionada à receptividade endometrial em pacientes submetidos à embolização do mioma uterino / Evaluation of gene expression related to endometrial receptivity in patients undergoing uterine leiomyoma embolizationSandro Garcia Hilário 29 May 2012 (has links)
OBJETIVO: Avaliar a receptividade endometrial de pacientes submetidas à embolização do mioma uterino, analisando a expressão gênica de LIF, IL-11, IL-6, claudina-4, HoxA-10, HoxA-11, receptor de estrogênio e receptor de progesterona antes e após este procedimento. CASUÍSTICA E MÉTODOS: Foram colhidas biópsias aspirativas de endométrio de 30 pacientes previamente à embolização do mioma uterino e repetida a coleta 3 a 4 meses após este procedimento. A média etária do grupo estudado foi de 36,2 anos. O volume uterino médio pré-embolização foi de 662,1 cc e o pós-embolização foi de 338,2 cc, medidos através de ressonância nuclear magnética. INTERVENÇÃO: As amostras de endométrio foram analisadas pela técnica de RT-PCR para os genes LIF, IL-11, IL-6, claudina-4, HoxA-10, HoxA-11, receptor de estrogênio e receptor de progesterona. RESULTADOS: Dentre os genes estudados, LIF (p=0,005), IL-11 (p=0,001) e HoxA-11 (p=0,021) apresentaram redução estatisticamente significante da expressão no endométrio após a embolização. Os demais genes não apresentaram alteração da expressão estatisticamente significante. CONCLUSÃO: Houve alteração da expressão de genes relacionados à receptividade endometrial, no endométrio de pacientes tratadas pela técnica da embolização do mioma uterino / OBJECTIVE: Assessing endometrial receptivity in patients undergoing uterine fibroid embolization by analyzing the gene expression of LIF, IL-11, IL-6, claudin-4, Hoxa-10, Hoxa-11, estrogen receptor and progesterone receptor before and after this procedure. METHODS: Endometrial aspiration biopsies were collected from 30 patients prior to embolization of uterine myoma, and the collections were repeated 3 to 4 months after this procedure. The average age of the study group was 36.2 years old. The mean uterine volume pre-embolization was 662. 1 cc and post-embolization was 338.2cc as measured by Magnectic Resonance Imaging (MRI). INTERVENTION: Endometrial samples were analyzed by RT-PCR for genes LIF, IL-11, IL-6, claudin-4, Hoxa-10, Hoxa-11, estrogen receptor and progesterone receptor. RESULTS: Among the studied genes, LIF (p=0.005), IL-11 (p=0.001) and Hoxa-11 (p=0.021) showed statistically significant reduction of expression in the endometrium after embolization. The remaining genes showed no statistically significant change in expression. CONCLUSION: There was altered expression of genes related to endometrial receptivity in the endometrium of patients treated by the technique of embolization of uterine myoma
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Avaliação clínica e técnica do tratamento endovascular percutâneo na síndrome da congestão pélvica através da técnica de embolização / Clinical and technical evaluation of transcatheter embolotherapy of the pelvic congestion syndromeFelipe Nasser 26 March 2007 (has links)
Um conjunto de evidências sugere que a síndrome da congestão pélvica está associada às varizes pélvicas. A congestão pélvica é explicada em muitos casos pela insuficiência das veias ovarianas em drenar o fluxo venoso dos ovários. No presente estudo, realizou-se a avaliação clínica e técnica do tratamento endovascular percutâneo na síndrome da congestão pélvica através da técnica de embolização. Foram tratadas 113 mulheres, das quais 100 foram acompanhadas pelo período de um ano e a análise dos resultados foi baseada nessa amostra. Os resultados clínicos foram baseados na avaliação da sintomatologia durante o período de acompanhamento, com a utilização da escala visual analógica. A avaliação técnica baseou-se no sucesso da realização dos procedimentos e na avaliação das complicações. As pacientes selecionadas com diagnóstico clínico da síndrome foram submetidas ao estudo angiográfico que revelou insuficiência das veias ovarianas previamente ao tratamento por embolização. Obteve-se sucesso técnico em todos os casos, caracterizado pela possibilidade de realização do cateterismo seletivo das veias ovarianas e ilíacas internas com embolização das mesmas. A remissão total dos sintomas foi observada em 37 pacientes (32.7%) e parcial em 63 pacientes (55.4%). Foi observado significativo alívio dos sintomas (p < 0,001), confirmados pela redução dos valores obtidos através da escala analógica visual. A principal complicação foi a migração do agente embolizante metálico, no entanto, com resolução endovascular de todos os casos e sem repercussão clínica. O tratamento endovascular das varizes pélvicas por meio da embolização apresentou resultados satisfatórios em relação aos sintomas apresentados e mostrou-se como método seguro e com baixos índices de complicação. / A great body of evidence suggests that the pelvic congestion syndrome is associated to female varicocile. Pelvic congestion is explained in many cases by ovarian and internal iliac vein insufficiency. The endpoint of the study was the measurement of clinical outcomes and technical success of transcatheter embolotherapy in order to obtain relief of symptoms. The treatment group included 113 patients but only 100 were submitted for a follow up period. We had initial technical success rate of the ovarian and internal iliac vein embolization in all cases. It was used a visual analog scale (VAS) during the 12 months follow up period. The selected patients with the diagnosis of the syndrome were submitted to an angiographic evaluation to reveal ovaric and internal iliac vein insufficiency previous embolization. The technical success was determined by the ability to successfully embolize the ovarian and internal ilac varices and the clinical evaluation by the improvement of symptoms after the following period. A total relief of symptoms was observed in 37 patients (32.7%) and partial relief in 63 (55.4%). Nevertheless, it was seen an important general relief of every symptom (p < 0.001), as well a reduction of the values. The main complication was coil distal embolization, nevertheless, all of them were solved by endovascular approach without clinical repercussion. The transcatheter embolotherapy of the pelvic congestion syndrome provides significant symptomatic improvement, initial technical success and showed no significant long-term complications.
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Désendothélialisation des anévrismes lors du traitement endovasculaire : une nouvelle approche pour prévenir les endofuitesBonneviot, Marie-Christine January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
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Endovascular treatment of an abdominal aortic aneurysm:mid-term results and management of a type II endoleakNevala, T. (Terhi) 09 March 2010 (has links)
Abstract
Endovascular aneurysm repair (EVAR) is a minimally invasive alternative to open surgery to exclude an abdominal aortic aneurysm from the circulation to avert a rupture. The aim of this thesis was to evaluate the early and mid-term results of EVAR using the Zenith® stent-graft (Cook Inc, Bloomington, IN, USA) in asymptomatic and symptomatic abdominal aortic aneurysm (AAA) patients in three Finnish university hospitals. Furthermore, the aim was to study whether preoperative embolization of the inferior mesenteric artery (IMA) before EVAR decreases the incidence of a type II endoleak or has an effect on the aneurysm sac shrinkage. Finally, the results after secondary interventions for a type II endoleak were evaluated.
Two hundred six patients underwent elective endovascular repair of an intact AAA. The use of the Zenith® stent-graft was associated with good early and mid-term results. The thirty-day mortality rate (2.9%) was in accordance with other EVAR studies. Only one late aneurysm-related death occurred in this series, whilst no patients died of a late aneurysm rupture. No stent-graft migrations or fractures were observed. Endoleak, defined as persistent blood flow outside the graft and within the aneurysm sac, remains a long-term problem with EVAR. The overall endoleak incidence was 34.6%. A type II endoleak (retrograde perfusion via aortic side branches) occurred in 52 patients (25.4%).
EVAR was performed for 14 patients with a symptomatic, unruptured AAA. The median delay from admission to intervention was 4 days. EVAR of a symptomatic, unruptured AAA was associated with a favourable outcome even in patients with a very high operative risk. There were no perioperative deaths.
Altogether forty patients treated at Kuopio University Hospital had a patent IMA on preoperative computed tomography (CT) and were treated successfully with coil embolization before EVAR. Thirty-nine patients who underwent EVAR at Oulu University Hospital without preoperative embolization of a patent IMA served as a control group. Preoperative coil embolization of the IMA significantly reduced the incidence of type II endoleaks after EVAR, but the present study failed to show any influence on late postoperative aneurysm sac shrinkage.
Overall, 14 patients underwent a secondary intervention to repair the type II endoleak. Ten patients had transarterial embolization and four patients had translumbar embolization. The results were unsatisfactory; clinical success after the first secondary intervention was achieved in only two patients in the transarterial embolization group and three patients in the translumbar embolization group. These results seem to favour direct translumbar embolization rather than transarterial embolization.
In conclusion, EVAR with the Zenith® stent-graft is effective in excluding AAAs from the circulation and is associated with good mid-term results.
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Microsphères d’embolisation chargées en doxorubicine : Apports des microspectroscopies optiques pour étudier l’influence de la taille et de la concentration chargée sur les propriétés d’élution et les effets tissulaires / Drug eluting beads loaded with doxorubicin : Contributions of optical microspectroscopy to study the effect of beads size and amount of drug loaded on release properties and tissue damages.D'inca, Hadrien 26 January 2015 (has links)
Les microsphères d'embolisation, apparues dans les années 2000, sont des dispositifs médicaux dirigées contre les tumeurs hépatiques non opérables. Elles sont calibrés et peuvent être chargées en anticancéreux. Ces avancées majeures permettent de contrôler le niveau d'occlusion et la concentration en principe actif à injecter dans la tumeur. Cependant, le type, la taille des microsphères ou encore la concentration en anticancéreux varient d'un centre à un autre et d'un pays à un autre. Notre travail vise à comparer, sur des modèles de tumeurs hépatiques, les propriétés d'élution et l'efficacité antitumorale de différentes préparations de microsphères. La microspectroscopie infrarouge est utilisée pour mesurer la quantité de doxorubicine présente dans les microsphères à différents délais alors que la microspectrofluorimétrie permet d'évaluer la concentration et la distribution de la doxorubicine autour des billes. L'évaluation de l'activité antitumorale du traitement est mesurée sur les images spectrales infrarouge grâce à un modèle de prédiction et confirmée par un examen histopathologique. Les résultats ont montré que la vitesse d'élution dépend des propriétés physicochimiques de la microsphère, de sa taille et de la concentration de chargement. Les concentrations tissulaires de doxorubicine mesurées induisent une réduction significative de la viabilité tumorale. Le model de prédiction est un outil robuste et précis pour évaluer les modifications tissulaires. Ces résultats permettent de formuler des hypothèses mécanistiques sur l'activité antitumorale de différentes préparations de microsphères afin d'optimiser leur utilisation dans une stratégie thérapeutique clinique. / Transarterial chemoembolization is the most common treatment for patients with unresectable liver tumors. Calibrated drug eluting beads offer the advantages of controlling the level of occlusion, the amount of drug delivered, and the duration of drug delivery to the tumor. However, optimal procedure still remains unanswered and treatments differ through the use of various beads sizes or dose of loading. Our work is to compare, on experimental liver tumor model, the release properties and antitumor effects for different preparations of doxorubicin eluting beads. The amount of drug retained inside the beads, at different time point, is assessed by infrared microspectroscopy. Doxorubicin concentration and distribution in the tissue are determined by microspectrofluorimetry. Tissue modifications are quantified by a prediction model on infrared images and compared with the conventional pathological examination of stained tissue sections. Results show that elution rate of doxorubicin depend on the beads composition, the size and the loaded concentration. The doxorubicin tissue concentration induces a significant decrease of tumor viability. The prediction model established by infrared microspectroscopy is an accurate and robust tool to quantify tissue modifications. These results allow the formulation of mechanistic hypotheses on antitumor activity of different preparations of beads to optimize their use in a clinical therapeutic strategy.
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Strain ultrasound elastography of aneurysm sac content after randomized endoleak embolization with sclerosing and non-sclerosing chitosan-based hydrogels in a preclinical modelSivakumaran, Lojan 08 1900 (has links)
Mise en contexte : La réparation endovasculaire des anévrismes de l’aorte abdominale est limitée par le développement des endofuites, qui nécessite un suivi à long terme par imagerie. L’élastographie sonore de déformation a été proposée comme méthode complémentaire pour aider à la détection des endofuites et la caractérisation des propriétés mécaniques des anévrismes. On s’intéresse ici également à la possibilité de suivre l’embolisation des endofuites, qui est indiquée dans certains cas mais dont le succès est variable. Un nouvel agent d’embolisation a été récemment créé en combinant un hydrogel de chitosane radio-opaque (CH) et le sclérosant tetradecyl sulfate de sodium (STS), qui s’appelle CH-STS. Le CH-STS démontre des propriétés mécaniques in vitro favorables, mais son comportement in vivo et son effet sur l’évolution du sac par rapport à un agent non-sclérosant pourraient être mieux caractérisés. L’objectif de cette étude était la caractérisation des propriétés mécaniques des composantes des endofuites embolisées avec CH-STS et CH avec élastographie sonore de déformation.
Méthodologie : Des anévrismes bilatéraux avec endofuites de type I ont été créés au niveau des artères iliaques communes chez neuf chiens. Chez chaque sujet, une endofuite a été embolisée avec CH, et l’autre, avec CH-STS, d’une façon aléatoire et aveugle. Des images d’échographie duplex et des cinéloops pour élastographie sonore de déformation ont été acquis à 1 semaine, 1 mois, 3 mois et (chez 3 sujets) 6 mois post-embolisation. La tomodensitométrie a été faite à 3 mois et (si pertinente) 6 mois post-embolisation. L’histopathologie a été faite au sacrifice. Les études radiologiques et les données d’histopathologie ont été co-enregistrées pour définir trois régions d’intérêt sur les cinéloops : l’agent d’embolisation (au sacrifice), le thrombus intraluminal (au sacrifice) et le sac anévrismal (pendant chaque suivi). L’élastographie sonore de déformation a été faite avec les segmentations par deux observateurs indépendants. La déformation axiale maximale (DAM) a été le critère d’évaluation principal. Les analyses statistiques ont été faites avec des modèles mixtes linéaires généralisés et des coefficients de corrélations intraclasses (ICCs).
Résultats : Des endofuites résiduelles ont été trouvées dans 7/9 (77.8%) et 4/9 (44.4%) des anévrismes embolisés avec CH et CH-STS, respectivement. Le CH-STS a eu une DAM 66 % plus basse (p < 0.001) que le CH. Le thrombus a eu une DAM 37% plus basse (p = 0.010) que le CH et 77% plus élevée (p = 0.079) que le CH-STS. Il n’y avait aucune différence entre les thrombi associés avec les deux traitements. Les sacs anévrismaux embolisés avec CH-STS ont eu une DAM 29% plus basse (p < 0.001) que ceux embolisés avec CH. Des endofuites résiduelles ont été associées avec une DAM du sac anévrismal 53% plus élevée (p < 0.001). Le ICC pour la DAM a été de 0.807 entre les deux segmentations.
Conclusion : Le CH-STS confère des valeurs de déformations plus basses aux anévrismes embolisés. Les endofuites persistantes sont associées avec des déformations plus élevées du sac anévrismal. / Background: Endovascular aneurysm repair (EVAR) is the modality of choice for the treatment of abdominal aortic aneurysms (AAAs). EVAR is limited by the development of endoleaks, which necessitate long-term imaging follow-up. Conventional follow-up modalities suffer from unique limitations. Strain ultrasound elastography (SUE) has been recently proposed as an imaging adjunct to detect endoleaks and to characterize aneurysm mechanical properties. Once detected, certain endoleaks may be treated with embolization; however, success is limited. In this context, the embolic agent CH-STS—containing a chitosan hydrogel and the sclerosant sodium tetradecyl sulphate (STS)—was created. CH-STS demonstrates favorable mechanical properties in vitro; however, its behavior in vivo and impact on sac evolution compared to a non-sclerosing chitosan-based embolic agent (CH) merit further characterization.
Purpose: To compare the mechanical properties of the constituents of endoleaks embolized with CH and CH-STS—including the agent, the intraluminal thrombus (ILT), and the overall sac—via SUE.
Methods: Bilateral common iliac artery aneurysms with type I endoleaks were created in nine dogs. In each animal, one endoleak was randomly embolized with CH, and the other with CH-STS. Duplex ultrasound (DUS) and radiofrequency cine loops were acquired at 1 week, 1 month, 3 months, and—in 3 subjects—6 months post-embolization. Contrast-enhanced CT was performed at 3 months and—where applicable—6 months post-embolization. Histopathological analysis was performed at time of sacrifice. Radiological studies and histopathological slides were co-registered to identify three regions of interest (ROIs) on the cine loops: embolic agent (at sacrifice), ILT (at sacrifice), and aneurysm sac (at all follow-up times). SUE was performed using segmentations from two independent observers on the cine loops. Maximum axial deformation (MAD) was the main outcome. Statistical analysis was performed using general linear mixed models and intraclass correlation coefficients (ICCs).
Results: Residual endoleaks were identified in 7/9 (77.8%) and 4/9 (44.4%) aneurysms embolized with CH and CH-STS, respectively. CH-STS had a 66 % lower MAD (p < 0.001) than CH. The ILT had a 37% lower MAD (p = 0.010) than CH and a 77% greater MAD (p = 0.079; trending towards significance) than CH-STS. There was no difference in the ILT between treatment groups. Aneurysm sacs embolized with CH-STS had a 29% lower MAD (p < 0.001) than those with CH. Residual endoleak increased MAD of the aneurysm sac by 53% (p < 0.001), regardless of the agent used. The ICC for MAD was 0.807 between readers’ segmentations.
Conclusion: CH-STS confers lower strain values to embolized aneurysms. Persistent endoleaks result are associated with increased sac strain, which may be useful for clinical follow-up.
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