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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Die Rolle des iFlow-Algortithmus im Rahmen der endovaskulären Therapie von symptomatischen Nierenarterienstenosen / The role of the iFlow-algorithm within the endovascular treatment of symptomatic renal artery stenosis

Welsch, Stefan January 2021 (has links) (PDF)
Das Ziel dieser Arbeit war herauszufinden, ob der iFlow-Algorithmus als zusätzlicher Parameter zu Evaluierung des technischen Erfolgs einer Revaskularisation einer Nierenarterienstenose eingesetzt werden kann. Hierfür haben wir die „mean time to peak“ in Sekunden in den farbcodierten Bildern gemessen, um den Effekt einer Stentimplantation auf den Blutfluss zu eruieren. Im Verlauf haben wir dann getestet, ob unsere Ergebnisse den klinischen Verlauf unserer Patienten wiederspiegeln, um feststellen zu können, ob die syngo iFlow-Software den Erfolg der endovaskulären Therapie voraussagen kann. / The goal of this Dissertation was to evaluate the application of the iFlow-Algorithm as a supplementary tool to predict the technical success of renal artery revascularization. To accomplish this, we measured the mean time to peak in color coded DSA images in seconds to evaluate the effect of the endovascular stent implantation on the arterial blood flow. We then tested, if our findings also represent the clinical progress of our patients to see if the syngo iFlow-Software can predict a successful endovascular treatment.
2

Scanning Electron Microscopy and Histological Evaluation of Flow Divertors

Rakian, Audrey 01 January 2007 (has links)
The purpose of this study is to evaluate the endothelialization, exclusion of the aneurysm from circulation and intra-aneurysmal thrombus formation induced by the implantation of endovascular flow divertors for the purpose of bridging aneurysms. The design of the flow divertors was based on previous in vitro hemodynamic experiments in aneurysm models. The significance of this work is manifested in the development of a minimally invasive technology that may be employed for aneurysm treatment. Divertors with two different filament sizes and three different porosities were implanted in the rabbit elastase-induced aneurysm model and their effectiveness evaluated both angiographically and histologically. Preliminary results demonstrated that it is possible to achieve substantial reduction in intraaneurysmal flow immediately after device deployment. Angiographically, the aneurysms were excluded from the circulation with the medium and low porosity devices. In addition, the device performed as expected: smooth deployment, no intralumenal clot formation, and exclusion of aneurysm from the circulation without occluding other arterial branches. Additional data is needed to make definitive conclusions regarding endothelialization and the formation of a neointima.
3

Abordaje transesfenoidal endoscópico en patología sellar. Descripción y análisis de una nueva técnica en nuestro ámbito hospitalario. Comparación respecto a la vía transesfenoidal clásica.

Enseñat Nora, Joaquim 27 February 2008 (has links)
-OBJETIVOS: Sistematizar el abordaje endoscópico endonasal transesfenoidal. Valorar el grado de resección tumoral, complicaciones, grado de invasividad tumoral y estancia postoperatoria. Comparar esta nueva técnica con el abordaje sublabial microquirúrgico clásico. -MATERIAL y MÉTODOS: Estudio prospectivo no randomizado de 50 pacientes intervenidos en nuestro centro entre 2002 y 2006 de adenomas hipofisarios con diferentes grados de invasión del seno cavernoso según la clasificación de Knosp. Entre las variables del estudio se incluyeron los grados de invasión, los grados de resección postoperatoria (total, subtotal y parcial) con un seguimiento radiológico medio de 12 meses, lesión del n.óptico, panhipopituitrasimo postoperatorio, fístula de LCR, déficit de pares craneales, epistaxis, meningitis, diabetes insípida y lesión de arteria carótida. Nuestra serie consta de 27 varones y 23 mujeres, con una edad media de 48 años (19 - 80 años). En 23 casos se utilizó una vía transesfenoidal sublabial clásica y en 25 casos se realizó un abordaje transesfenoidal endoscópico. Las relaciones entre el método quirúrgico aplicado y las variables de naturaleza categórica del estudio se realizaron mediante tablas de contingencia y el cálculo del test Chi-cuadrado. Para el caso de tablas de contingencia 2X2 con valores esperados inferiores a 5 en alguna celda, se realizó el cálculo del test exacto de Fisher. En cuanto a la medición de la relación entre el método quirúrgico y las variables de naturaleza cuantitativa, ésta se realizó mediante un test T. La relación entre el método quirúrgico y a la invasión del tumor se realizó mediante una Regresión Logística No-Condicionada. La estimación del número de días de postoperatorio de los pacientes se realizó mediante un Análisis de la Covarianza (ANCOVA). -RESULTADOS: En nuestra experiencia la técnica endoscópica presenta un porcentaje de exéresis completa superior al de la técnica clásica (60% frente a 34,8%) y un mayor porcentaje de resección subtotal (32% frente 26%) existiendo una diferencia estadísticamente significativa (p=0,033). En contraposición no encontramos diferencias en cuanto a complicaciones. También hemos evidenciado que existe una diferencia estadísticamente significativa en cuanto a la estancia postoperatoria (p=0,111), reduciéndose ésta a la mitad (3 días) con la técnica endoscópica. Si bien no hemos encontrado diferencias significativas en cuanto al grado de invasividad tumoral y al grado de resección, un mayor grado de invasividad aumenta en 3,59 veces el riesgo de poco éxito de la operación.- DISCUSIÓN Y CONCLUSIONES: En nuestra experiencia con la técnica endoscópica obtenemos un mayor grado de resección quirúrgica y una estancia postoperatoria menor. No hemos observado diferencias en cuanto a las complicaciones. La técnica endoscópica es relativamente nueva y en vías de desarrollo; nos permite una mejor visión de las estructuras sellares y una menor invasividad, traduciéndose esto en mejores resultados y en una mayor confortabilidad para nuestros pacientes. / "ENDOSCOPIC ENDONASAL TRANSSPHENOIDAL APPROACH IN SELLAR TUMORS: ANALYSIS AND DESCRIPTION OF A NEW TECHNIQUE. COMPARISON WITH THE STANDARD SUBLABIAL TRANSEPTAL APPROACH". OBJECTIVE: In the present study we evaluate our experience regarding the treatment of pituitary adenomas. A comparison of the endoscopic transnasal vs the sublabial transseptal approach is illustrated.MATERIALS, METHODS: We consider 50 patients, 27 males and 23 females, the age range was between 19 to 80, with a mean of 48 years. All patients were operated upon by a single surgeon between 2002 and 2006. 23 cases were treated with a standard sublabial approach and 25 cases were with the endoscopic approach. The study population was evaluated with MRI and staged according to the Knosp classification. Postoperatively, the excision was classified as Complete, Subtotal or Partial. Mean follow up was 12 months. The variables considered for analysis include invasion grades, resection grades and complications. A Prospective no randomised study was performed. The relationship between surgical techniques and categorical variables was carried out using x-square and Fisher Exact tests. The relationship between surgical techniques and quantitative variables was carried out using a Student's T test.RESULTS: Complete resection was achieved in 60% of patients operated by the endoscopic approach vs 34,8% operated using a sublabial approach. Subtotal resection was 32% in the endoscopic group and 26% in sublabial group (p=0,033). Concerning surgical complications there were not statistical differences. On the contrary, patients operated endoscopically were discharged on postoperative day 3 (p=0,11) while patients operated by the sublabial approach were discharged on postoperative day 6. Higher invasive tumor grades were associated with a 3,59 times higher risk of non optimal surgical results. CONCLUSION: The endoscopic endonasal transsphenoidal approach improves the extent of tumor resection and reduce the postoperative stay. This approach is a new minimally invasive technique which provide a straight, multiangled, and close-up view of the midline areas around the sella.
4

Popliteal Artery Aneurysms: Rationale, Technique, and Results of Endovascular Treatment

Ying, Huang, Gloviczki, Peter 01 June 2008 (has links)
Endovascular repair of popliteal artery aneurysms has been used with increasing frequency in recent years. Advocates of the procedure claim a lower rate of complications, early return to work, no change in the quality of life, and long-term patency rates that are as favorable as those following open surgical repair. Unfortunately, data of only 1 prospective randomized study are available, and a recent meta-analysis showed a higher rate of early graft thromboses and more early reinterventions after endograft repair of popliteal artery aneurysms. Open, elective surgical repair with the vein graft has patency rates more than 90% in contemporary series. Current evidence only supports the use of stent grafts in those with high surgical risks and in the elderly.
5

Endovaskuläre Interventionen in der Behandlung der Epistaxis / Endovascular intervention in treatment refractory epistaxis

Sorour, Ahmed Tarek Ali Ibrahim January 2021 (has links) (PDF)
Trotz hoher Erfolgsrate und niedriger Komplikationsrate der arteriographischen Embolisation bei der Nasenblutung kommt diese Behandlungsmethode in vielen Institutionen nicht als Standard-Maßnahme im klinischen Kontext zum Einsatz und wird nur als alternativ im Falle eines Scheiterns der chirurgischen arteriellen Clippung in der Blutstillung eingesetzt. In der vorliegenden retrospektiven Arbeit wurden am Kopf- und Schädelbasiszentrum des Klinikums Fulda die Effizienz und die Sicherheit der perkutanen Embolisation der A. sphenopalatina mit Polyvinylalkohol-Partikeln (150-250 µm) in der Behandlung, der mit konservativen Maßnahmen refraktären Epistaxis untersucht. Methode: Retrospektive Analyse von 99 Patienten, die von Januar 2001 bis Dezember 2018 bei refraktärer, idiopathisch klassifizierter Epistaxis durch eine arteriographische endovaskuläre Embolisation behandelt wurden. Ergebnisse: Es wurden innerhalb des Berichtszeitraums insgesamt 100 Embolisationen bei Epistaxis durchgeführt. Nach Ausschluss von 2 Prozeduren mit bekannten Blutungsursachen wurden 98 Embolisationen bei 95 Patienten mit idiopathischer Epistaxis ausgewertet. Trotz technisch erfolgreicher Intervention in 95% der Fälle, war die Blutung in 81,6% der Fälle zu stillen. Leichte Komplikationen traten in 5% der Fälle auf. Schwere Komplikationen dagegen wurden in keinem einzigen Fall erfasst. Schlussfolgerung: Das Ergebnis dieser Untersuchung bestätigt die Rolle der angiografischen Embolisation der A. sphenopalatina sowohl als einer erfolgreichen, als auch als einer sicheren Methode in der Behandlung der konservativ refraktären Epistaxis. Aufgrund der geringen Invasivität, hohen Erfolgsrate und niedrigen Komplikationsrate sollte die transkutane Embolisation als Standard-Therapie nach dem Scheitern der konservativen Maßnahmen zur Blutstillung einer Epistaxis zum Einsatz kommen. Die chirurgische Blutstillung durch die arterielle Clippung sollte nur im Falle eines Misserfolgs der Embolisation als Verfahren der zweiten Wahl bei der Blutstillung eingesetzt werden. / Angiographic embolization is a successful method in treating refractory cases of epistaxis with a very low complication rate. MATERIALS AND METHODS: Retrospective analysis of 98 patients transferred or admitted with refractory epistaxis and treated with selective angiographic embolization from 2001 to 2018. RESULTS: The angiographic intervention was successful in 81,6% with minor complications in 5%, no major complications were registrated. CONCLUSIONS: Angiographic embolization is a clinically effective and minimal invasive method on treating severe epistaxis and should be used regularly after failing of conservative therapy.
6

Preditores de oclusão arterial proximal em pacientes com acidente vascular cerebral de circulação anterior, baseados na avaliação clínica e na tomografia de crânio não-contrastada / Predictors of proximal artery occlusion in patients with acute ischemic stroke of the anterior circulation based on clinical evaluation and noncontrast brain CT

Martins Filho, Rui Kleber do Vale 03 February 2016 (has links)
Introdução: Após os resultados contundentes dos novos estudos de tratamento endovascular no acidente vascular cerebral isquêmico (AVCi), a detecção precoce dos casos de oclusão arterial proximal (OAP) se tornou uma medida fundamental na avaliação inicial de pacientes com isquemia cerebral no pronto-socorro. Todavia, esse diagnostico torna-se desafiador em centros de menor estrutura ou países em desenvolvimento, onde o acesso a neuroimagem vascular, como a angioressonância ou a angiotomografia, é restrito.Objetivos: Avaliar a acurácia da escala do NIHSS e da atenuação da artéria cerebral média na detecção de oclusões proximais no AVC agudo de circulação anterior. Formular um algoritmo de detecção dessas lesões baseado nesses parâmetros.Método: Foram avaliados retrospectivamente 178 pacientes consecutivos com diagnostico de AVCi de circulação anterior, através de registro prospectivo de pacientes admitidos em unidade de emergência de um hospital acadêmico terciário durante o ano de 2014. Os valores de NIHSS da admissão e de atenuação da artéria cerebral media (ACM) na tomografia de crânio não-contrastada (TCNC) foram coletados por dois examinadores cegos para os achados da neuroimagem vascular realizada na admissão. Foram destacados os valores de atenuação absoluta do vaso no lado sintomático (VA) e de atenuação relativa (rVA), através de uma razão entre o lado sintomático e sua área homóloga (imagem em espelho) no vaso contralateral. Modelos de curva ROC, estatísticas C e regressão logística foram usados para definir OAP, através da realização de um escore com os preditores de OAP. Resultados:Os valores de NIHSS e de atenuação da ACM se associaram com a presença de oclusão proximal,com uma área sob a curva de 0,88 (p < 0,001) e 0,76 (p < 0,001). Um NIHSS de 10 na admissão obteve uma sensibilidade e um valor preditivo negativo de 96,7% e 97,4%, respectivamente. Um VA >= 50 obteve uma especificidade e um valor preditivo positivode 93,9% e 81%. O OAP escore, que inclui estes preditores, demonstrou uma acurácia ainda maior na deteção de OAP, através de uma area sob a curva de 0,92 (p < 0,001). Conclusão:Os valores de NIHSS e de atenuação da ACM em TCNC estão relacionados com a presença de OAP na fase aguda do AVC.Escores baseados nesses parâmetros, como o OAP escore, podem ser usados de forma acurada na detecção de oclusão proximal. Mais estudos são necessários para validar o OAP escore em um cenário multicêntrico / Introduction: After the results of the new endovascular trials that demonstrated a robust effect of endovascular treatment for acute ischemic stroke (AIS), early detection of proximal artery occlusion (PAO) has become a fundamental task during the initial assessment of acute stroke patients at the emergency department. Nevertheless, an accurate identification of PAO may be particularly challenging in smaller hospitals and in developing countries, areas with restricted assess to vascular neuroimaging modalities such as CTA and MRA.Objectives: Evaluation of NIHSS and attenuation of middle cerebral artery (MCA) in detecting PAO. Perform an algorithm to identify these lesions. Method:We retrospectively evaluated 178 consecutive patients with AIS of the anterior circulation included in a prospective stroke registry of patients admitted to an academic tertiary emergency unit in Brazil during 2014 that had a NCCT and a CTA at admission. NIHSS scores and attenuation of middle cerebralartery (MCA) on NCCT were collected by two experienced investigators that were blind to the CT angiography findings. We used a ratio between two ROIs (rVA) that were drawn on NCCT blinded to CT angiography: (i) on the region of highest vessel attenuation ipsilateral to the involved hemisphere and (ii) mirror ROI on the corresponding vessel segment of the contralateral hemisphere. We used ROC curve analysis, C-statistics and logistic regression to predict PAO, establishing a predictor score (PAO score). Results: NIHSS and vessel attenuation values were highly associated with the PAO with an area under the curve (AUC) of 0.88 (p < 0,001) and 0.76 (p < 0,001), respectively. An NIHSS of 10 at admission had a sensitivity and negative predictive value of 96,7% and 97,4%, respectively. TheVA >= 50 had specificity and positive predictive value of 93,9% and 81%, respectively. The POA score showed an even higher accuracy for the presence of POA, with an AUC of 0.92 (p < 0,001). Conclusion:NIHSS and CMA vessel attenuation on NCCT valuesare associated to PAO in patients with AIS of the anterior circulation. Algorithms based on these findings could be used to detect PAO in this context. Further studies are necessary to validate the PAO score in a multicenter setting
7

Estudo do tratamento endovascular para a estenose de artéria renal em rim transplantado / Study of endovascular treatment for renal artery stenosis in transplanted kidney

Braga, André Felipe Farias 27 November 2017 (has links)
Introdução: O transplante renal é a terapia substitutiva de escolha para a insuficiência renal crônica. O número absoluto de transplantes renais vem aumentando mundialmente e consequentemente as complicações deste procedimento têm sido evidenciadas com maior recorrência, dentre elas a estenose na artéria renal transplantada. A técnica endovascular vem mostrando bons resultados iniciais, com boa taxa de perviedade e baixa taxa de complicações pósoperatórias quando comparadas a técnica aberta para tratamento da estenose. O objetivo deste estudo foi avaliar os resultados primários da angioplastia da artéria renal do rim transplantado secundário a processo de re-estenose. Métodos: Realizado estudo retrospectivo no período de setembro de 2009 a outubro de 2015, baseado em protocolos de seguimento pós-transplante com perfil dos pacientes submetidos a tratamento por estenose em artéria de rim transplantado e o seguimento em curto prazo com critérios clínicos, laboratoriais e ultrassonográficos. Resultados: Dentre um total de 391 transplantes, 19 pacientes foram diagnosticados com Estenose na Artéria renal transplantada. Evidenciado um tempo médio entre o transplante e o diagnóstico de 172,6 dias. As estenoses ou acotovelamentos com alterações hemodinâmicas foram evidenciadas na anastomose (47%), no terço proximal (35%) e terço médio (18%) da artéria transplantada. Todos os pacientes foram submetidos a angioplastia com balão e posicionamento de stent metálico com sucesso técnico de 94,7 %. A creatinina média evoluiu de 3,63 mg/dl para 2,69 mg/dl em 24h e para 1,81 mg/dl em 30 dias (p<0.05). A taxa de filtração glomerular melhorou de 32,66 ml/min para 41,61 ml/min após 24 horas e 51,05 ml/min após 30 dias (p<0.05). Os critérios ultrassonográficos avaliados de velocidade da artéria renal e índice reno-iliaco (368,9 cm/seg e 3,71 pré angioplastia) normalizaram e se estabilizaram durante o período estudado (211,45 cm/seg e 1,69 90 dias pós angioplastia; p<0.05). Conclusão: A abordagem endovascular utilizando de angioplastia primária e colocação de stent metálico foi segura com boa uma taxa de sucesso técnico. O procedimento foi efetivo na melhora da função renal do enxerto transplantado e na correção das alterações ultrassonográficas evidenciadas no pré-operatório. / Introduction: Renal transplantation is the substitutive therapy of choice for chronic renal failure. The absolute number of renal transplants has increased worldwide and consequently the complications of this procedure have been evidenced with greater recurrence, among them stenosis in the transplanted renal artery. The endovascular technique has shown good initial results, with good patency rate and low rate of postoperative complications when compared to the open technique for stenosis treatment. The aim of this study was to evaluate the primary results of ATP from the renal artery of the transplanted kidney secondary to the restenosis process. Methods: A retrospective study was carried out from September 2009 to October 2015, based on post-transplant follow-up protocols with a profile of patients submitted to stenosis in a transplanted kidney artery and a short-term follow-up with clinical, laboratory and ultrasonographics criteria. Results: Out of a total of 391 transplants, 19 patients were diagnosed with transplanted renal artery stenosis. An average time between transplantation and the diagnosis of 172.6 days was evidenced. Stenting or flexing with hemodynamic changes were evident in the anastomosis (47%), in the proximal third (35%) and the middle third (18%) of the transplanted artery. All patients underwent balloon angioplasty and metallic stent placement with technical success of 94.7%. Mean creatinine increased from 3.63 mg / dL to 2.69 mg / dL in 24 hours and to 1.81 mg / dL in 30 days (p <0.05). The glomerular filtration rate improved from 32.66 ml / min to 41.61 ml / min after 24 hours and 51.05 ml / min after 30 days (p <0.05). The ultrasound criteria evaluated for renal artery velocity and reno-iliac index (368.9 cm / sec and 3.71 pre angioplasty) normalized and stabilized during the study period (211.45 cm / sec and 1.69 Angioplasty, p <0.05). Conclusion: The endovascular approach using primary angioplasty and stent placement was safe with good technical success rate. The procedure was effective in improving the renal function of the transplanted graft and in correcting the ultrasound changes evidenced in the preoperative period.
8

Preditores de oclusão arterial proximal em pacientes com acidente vascular cerebral de circulação anterior, baseados na avaliação clínica e na tomografia de crânio não-contrastada / Predictors of proximal artery occlusion in patients with acute ischemic stroke of the anterior circulation based on clinical evaluation and noncontrast brain CT

Rui Kleber do Vale Martins Filho 03 February 2016 (has links)
Introdução: Após os resultados contundentes dos novos estudos de tratamento endovascular no acidente vascular cerebral isquêmico (AVCi), a detecção precoce dos casos de oclusão arterial proximal (OAP) se tornou uma medida fundamental na avaliação inicial de pacientes com isquemia cerebral no pronto-socorro. Todavia, esse diagnostico torna-se desafiador em centros de menor estrutura ou países em desenvolvimento, onde o acesso a neuroimagem vascular, como a angioressonância ou a angiotomografia, é restrito.Objetivos: Avaliar a acurácia da escala do NIHSS e da atenuação da artéria cerebral média na detecção de oclusões proximais no AVC agudo de circulação anterior. Formular um algoritmo de detecção dessas lesões baseado nesses parâmetros.Método: Foram avaliados retrospectivamente 178 pacientes consecutivos com diagnostico de AVCi de circulação anterior, através de registro prospectivo de pacientes admitidos em unidade de emergência de um hospital acadêmico terciário durante o ano de 2014. Os valores de NIHSS da admissão e de atenuação da artéria cerebral media (ACM) na tomografia de crânio não-contrastada (TCNC) foram coletados por dois examinadores cegos para os achados da neuroimagem vascular realizada na admissão. Foram destacados os valores de atenuação absoluta do vaso no lado sintomático (VA) e de atenuação relativa (rVA), através de uma razão entre o lado sintomático e sua área homóloga (imagem em espelho) no vaso contralateral. Modelos de curva ROC, estatísticas C e regressão logística foram usados para definir OAP, através da realização de um escore com os preditores de OAP. Resultados:Os valores de NIHSS e de atenuação da ACM se associaram com a presença de oclusão proximal,com uma área sob a curva de 0,88 (p < 0,001) e 0,76 (p < 0,001). Um NIHSS de 10 na admissão obteve uma sensibilidade e um valor preditivo negativo de 96,7% e 97,4%, respectivamente. Um VA >= 50 obteve uma especificidade e um valor preditivo positivode 93,9% e 81%. O OAP escore, que inclui estes preditores, demonstrou uma acurácia ainda maior na deteção de OAP, através de uma area sob a curva de 0,92 (p < 0,001). Conclusão:Os valores de NIHSS e de atenuação da ACM em TCNC estão relacionados com a presença de OAP na fase aguda do AVC.Escores baseados nesses parâmetros, como o OAP escore, podem ser usados de forma acurada na detecção de oclusão proximal. Mais estudos são necessários para validar o OAP escore em um cenário multicêntrico / Introduction: After the results of the new endovascular trials that demonstrated a robust effect of endovascular treatment for acute ischemic stroke (AIS), early detection of proximal artery occlusion (PAO) has become a fundamental task during the initial assessment of acute stroke patients at the emergency department. Nevertheless, an accurate identification of PAO may be particularly challenging in smaller hospitals and in developing countries, areas with restricted assess to vascular neuroimaging modalities such as CTA and MRA.Objectives: Evaluation of NIHSS and attenuation of middle cerebral artery (MCA) in detecting PAO. Perform an algorithm to identify these lesions. Method:We retrospectively evaluated 178 consecutive patients with AIS of the anterior circulation included in a prospective stroke registry of patients admitted to an academic tertiary emergency unit in Brazil during 2014 that had a NCCT and a CTA at admission. NIHSS scores and attenuation of middle cerebralartery (MCA) on NCCT were collected by two experienced investigators that were blind to the CT angiography findings. We used a ratio between two ROIs (rVA) that were drawn on NCCT blinded to CT angiography: (i) on the region of highest vessel attenuation ipsilateral to the involved hemisphere and (ii) mirror ROI on the corresponding vessel segment of the contralateral hemisphere. We used ROC curve analysis, C-statistics and logistic regression to predict PAO, establishing a predictor score (PAO score). Results: NIHSS and vessel attenuation values were highly associated with the PAO with an area under the curve (AUC) of 0.88 (p < 0,001) and 0.76 (p < 0,001), respectively. An NIHSS of 10 at admission had a sensitivity and negative predictive value of 96,7% and 97,4%, respectively. TheVA >= 50 had specificity and positive predictive value of 93,9% and 81%, respectively. The POA score showed an even higher accuracy for the presence of POA, with an AUC of 0.92 (p < 0,001). Conclusion:NIHSS and CMA vessel attenuation on NCCT valuesare associated to PAO in patients with AIS of the anterior circulation. Algorithms based on these findings could be used to detect PAO in this context. Further studies are necessary to validate the PAO score in a multicenter setting
9

Estudo do tratamento endovascular para a estenose de artéria renal em rim transplantado / Study of endovascular treatment for renal artery stenosis in transplanted kidney

André Felipe Farias Braga 27 November 2017 (has links)
Introdução: O transplante renal é a terapia substitutiva de escolha para a insuficiência renal crônica. O número absoluto de transplantes renais vem aumentando mundialmente e consequentemente as complicações deste procedimento têm sido evidenciadas com maior recorrência, dentre elas a estenose na artéria renal transplantada. A técnica endovascular vem mostrando bons resultados iniciais, com boa taxa de perviedade e baixa taxa de complicações pósoperatórias quando comparadas a técnica aberta para tratamento da estenose. O objetivo deste estudo foi avaliar os resultados primários da angioplastia da artéria renal do rim transplantado secundário a processo de re-estenose. Métodos: Realizado estudo retrospectivo no período de setembro de 2009 a outubro de 2015, baseado em protocolos de seguimento pós-transplante com perfil dos pacientes submetidos a tratamento por estenose em artéria de rim transplantado e o seguimento em curto prazo com critérios clínicos, laboratoriais e ultrassonográficos. Resultados: Dentre um total de 391 transplantes, 19 pacientes foram diagnosticados com Estenose na Artéria renal transplantada. Evidenciado um tempo médio entre o transplante e o diagnóstico de 172,6 dias. As estenoses ou acotovelamentos com alterações hemodinâmicas foram evidenciadas na anastomose (47%), no terço proximal (35%) e terço médio (18%) da artéria transplantada. Todos os pacientes foram submetidos a angioplastia com balão e posicionamento de stent metálico com sucesso técnico de 94,7 %. A creatinina média evoluiu de 3,63 mg/dl para 2,69 mg/dl em 24h e para 1,81 mg/dl em 30 dias (p<0.05). A taxa de filtração glomerular melhorou de 32,66 ml/min para 41,61 ml/min após 24 horas e 51,05 ml/min após 30 dias (p<0.05). Os critérios ultrassonográficos avaliados de velocidade da artéria renal e índice reno-iliaco (368,9 cm/seg e 3,71 pré angioplastia) normalizaram e se estabilizaram durante o período estudado (211,45 cm/seg e 1,69 90 dias pós angioplastia; p<0.05). Conclusão: A abordagem endovascular utilizando de angioplastia primária e colocação de stent metálico foi segura com boa uma taxa de sucesso técnico. O procedimento foi efetivo na melhora da função renal do enxerto transplantado e na correção das alterações ultrassonográficas evidenciadas no pré-operatório. / Introduction: Renal transplantation is the substitutive therapy of choice for chronic renal failure. The absolute number of renal transplants has increased worldwide and consequently the complications of this procedure have been evidenced with greater recurrence, among them stenosis in the transplanted renal artery. The endovascular technique has shown good initial results, with good patency rate and low rate of postoperative complications when compared to the open technique for stenosis treatment. The aim of this study was to evaluate the primary results of ATP from the renal artery of the transplanted kidney secondary to the restenosis process. Methods: A retrospective study was carried out from September 2009 to October 2015, based on post-transplant follow-up protocols with a profile of patients submitted to stenosis in a transplanted kidney artery and a short-term follow-up with clinical, laboratory and ultrasonographics criteria. Results: Out of a total of 391 transplants, 19 patients were diagnosed with transplanted renal artery stenosis. An average time between transplantation and the diagnosis of 172.6 days was evidenced. Stenting or flexing with hemodynamic changes were evident in the anastomosis (47%), in the proximal third (35%) and the middle third (18%) of the transplanted artery. All patients underwent balloon angioplasty and metallic stent placement with technical success of 94.7%. Mean creatinine increased from 3.63 mg / dL to 2.69 mg / dL in 24 hours and to 1.81 mg / dL in 30 days (p <0.05). The glomerular filtration rate improved from 32.66 ml / min to 41.61 ml / min after 24 hours and 51.05 ml / min after 30 days (p <0.05). The ultrasound criteria evaluated for renal artery velocity and reno-iliac index (368.9 cm / sec and 3.71 pre angioplasty) normalized and stabilized during the study period (211.45 cm / sec and 1.69 Angioplasty, p <0.05). Conclusion: The endovascular approach using primary angioplasty and stent placement was safe with good technical success rate. The procedure was effective in improving the renal function of the transplanted graft and in correcting the ultrasound changes evidenced in the preoperative period.
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Polymeric Endo-Aortic Paving (PEAP): Initial Development of a Novel Treatment for Abdominal Aortic Aneurysms

Ashton, John Hardy January 2010 (has links)
Abdominal aortic aneurysm (AAA) is a prevalent disease in developed countries. While endovascular aneurysm repair is fairly successful, it has shortcomings. Polymeric endoluminal paving and sealing is a method that has previously been developed to treat a range of diseases. Our goal is to further develop this technique to treat AAA, a process we have named polymeric endo-aortic paving (PEAP). We hypothesize that PEAP will overcome many of the limitations associated with EVAR by providing a minimally invasive treatment which can be used on patients with complicated AAA geometries and reducing incidence of migration and endoleak. Additionally, we plan to incorporate drug delivery into PEAP to improve efficacy. The purpose of this work was to evaluate a potential graft material for PEAP and to develop a thrombus mimic which will aid in further PEAP development. Blends of polycaprolactone/polyurethane (PCL/PU) were assessed by characterizing their mechanical, thermoforming, and degradation properties. PCL/PU grafts have a similar stiffness to aortic tissue and can be thermoformed at temperatures approaching 37 degrees C. Blending PCL with PU significantly reduces PCL's degradation. An anisotropic hyperelastic strain energy function was developed for the PCL/PU blends and finite element modeling (FEM) was used to show that stress reduction on the AAA wall that can be achieved by PEAP is similar to current EVAR. Stiffness varies throughout the AAA thrombus, and thrombus mimics were developed that have similar stiffness, components, and structure to native AAA thrombus.

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