京都大学 / 新制・論文博士 / 博士(医学) / 乙第13540号 / 論医博第2280号 / 新制||医||1066(附属図書館) / (主査)教授 小濱 和貴, 教授 近藤 尚己, 教授 妹尾 浩 / 学位規則第4条第2項該当 / Doctor of Medical Science / Kyoto University / DFAM

Introdução: a dor pélvica crônica é um problema que afeta uma significativa parcela de pacientes que buscam atendimento ginecológico. Dentre suas etiologias, destaca-se a síndrome de congestão pélvica, causada por insuficiência venosa pélvica. A justificativa deste estudo foi verificar se a técnica endovascular pode ser considerada estratégia terapêutica efetiva e válida para a população brasileira. Objetivo: avaliar a resposta clínica e a taxa de sucesso após embolização de varizes periuterinas em pacientes com dor pélvica crônica secundária à síndrome de congestão pélvica, e relatar a segurança do tratamento endovascular e o índice de complicações. Materiais e métodos: coorte retrospectiva de pacientes submetidas a tratamento endovascular da síndrome de congestão pélvica em nosso serviço, no período de janeiro de 2012 até novembro de 2015. Foram analisados dados relativos aos antecedentes das pacientes, achados de exames de imagem, veias embolizadas, taxa de complicações e resposta clínica baseada na escala visual analógica de dor. Resultados: Foi realizada embolização de varizes periuterinas em 22 pacientes no período estudado, sendo que quatro delas realizaram uma segunda embolização. Foi observada redução da dor em 17 pacientes considerando-se a primeira embolização (77.3%) e em 3 pacientes na segunda embolização (75%). Foram observadas complicações menores em 5 pacientes, como hipotensão postural, dor no pós-operatório e perfuração venosa sem repercussão clínica durante o procedimento. Conclusão: O presente estudo apresentou resultados satisfatórios da embolização de varizes periuterinas na redução dos sintomas de pacientes com dor pélvica crônica secundária à síndrome de congestão pélvica, mostrando-se como método seguro. / Introduction: Chronic pelvic pain accounts a significant number of gynecologic referrals. Among its etiologies, there is the pelvic congestion syndrome, caused by pelvic venous insufficiency. The rationale of this study was to determine whether endovascular technique can be considered effective and valid therapeutic strategy for the Brazilian population. Objective: To evaluate the clinical response and the success rate after periuterine varices embolization in patients with chronic pelvic pain secondary to pelvic congestion syndrome, and report the safety of endovascular treatment and the rate of complications. Materials and methods: Retrospective cohort of patients undergoing endovascular treatment of pelvic congestion syndrome in our department from January 2012 to November 2015. Data were analyzed on the background of patients, imaging findings, embolized veins, rate complications and clinical response based on visual analog pain scale. Results: We performed peiruterine varices embolization in 22 patients during the study period, four of which held a second embolization. 17 patients reported a reduction in pelvic pain considering the first embolization (77.3%) and 3 patients in the second embolization (75%). Minor complications were observed in 5 patients, such as postural hypotension, postoperative pain and venous perforation during the procedure, without clinical repercussion. Conclusion: The present study showed satisfactory improvement of clinical symptons after periuterine varices embolization in patients with chronic pelvic pain secondary to pelvic congestion syndrome, showing up as a safe method.

Introdução: A alta incidência de oclusão incompleta e recanalização dos aneurismas intracranianos de colo largo tratados por via endovascular levaram ao desenvolvimento de novas técnicas, entre elas o uso do Onyx ®. Objetivos: avaliar a eficiência do agente embólico líquido Onyx® em produzir oclusão completa dos aneurismas intracranianos de colo largo e avaliar a estabilidade do tratamento aos 6 meses e aos 18 meses, por meio de controles angiográficos. Casuística e métodos: Esta tese foi realizada na Seção de Neuroradiologia Intervencionista da Med Imagem, do Hospital São Joaquim da Real e Benemérita Associação Portuguesa de Beneficência de São Paulo, através da revisão de dados clínicos e radiológicos de 69 pacientes tratados pelo autor, com 84 aneurismas intracranianos de colo largo no período de julho de 2002 a fevereiro de 2006. Dez pacientes eram do sexo masculino e 59 do sexo feminino, com idade variando de 24 anos a 86 anos (mediana de 52 anos). Todos os aneurismas tinham origem lateral à artéria e apresentavam pelo menos um dos critérios usados para definir colo largo - colo maior que 4 mm de diâmetro e relação saco/colo menor que 1,5. Cinqüenta aneurismas eram pequenos, 30 grandes e quatro gigantes (diâmetro máximo menor que 12mm, de 12mm a 25mm e maiores que 25mm, respectivamente). As apresentações clínicas mais comuns foram: achado incidental em 34 pacientes, pós-hemorragia sub aracnóide e recanalização após tratamento com espirais destacáveis em 10. A maioria dos aneurismas era da artéria carótida interna (76 aneurismas). Controles angiográficos foram feitos ao final, aos seis meses e aos 18 meses do tratamento (controles I, II e III respectivamente), sendo analisados principalmente o grau de oclusão (completa ou incompleta), incidência de recanalização e complicações clínicas. Avaliação estatística foi feita pelo método de Kaplan-Meier para o percentual cumulativo de oclusão completa e percentual de recanalização e análise univariada e multivariada dos fatores preditivos de oclusão total imediata e tardia através de regressão logística. Resultados: O índice de oclusão completa foi de 65,5%, 84,6% e de 90,3% para todos os aneurismas, nos controles I, II e III respectivamente. Estes índices foram de 74%, 95,1% e de 95,2% para os aneurismas pequenos e de 53,3%, 70% e de 80% para os aneurismas grandes nos controles I, II e III respectivamente. Oclusão completa ocorreu em 50% dos aneurismas gigantes nos controles I e II, sem haver controle III neste grupo. Recanalização ocorreu em 3 aneurismas (4,6%). O porcentual cumulativo de oclusão completa foi de 97,63% (IC de 95% variando de 95,27 a 100) para os aneurismas pequenos aos 9 meses e de 83,86% (IC de 95% variando de 67,73 a 100) para os aneurismas grandes aos 21 meses. Três pacientes faleceram (4,3%), havendo relação com o procedimento em dois (2,9%). Morbidade permanente ocorreu em cinco pacientes (7,2%), sendo incapacitante em um (1,4%). Conclusões: 1. O uso do Onyx® foi eficiente na oclusão completa dos aneurismas intracranianos de colo largo. 2. O tratamento foi estável nos controles angiográficos aos 6 meses e aos 18 meses. / Introduction: The high rate of incomplete occlusion and intracranial large neck aneurysms recanalization lead to the development of new techniques, including the use of Onyx®. Purpose: to evaluate the efficacy of the liquid embolic system Onyx ® to produce completes occlusion of the intracranial large neck aneurysms and evaluates the stability of the treatment at 6 month and 18 month angiographic control. Materials and Methods: this thesis has been performed at Section of Interventional Neuroradiology of Med Imagem, at the Hospital São Joaquim da Real e Benemérita Associação Portuguesa de Beneficência de São Paulo, based on a review of clinical and radiological records of 69 patients treated by the author, harboring 84 large neck intracranial aneurysms between July 2002 and February 2006. Ten patients were male and 59 female, with age ranging from 24 to 86 years old. All aneurysms were lateral to the parent vessel and were wide neck (neck > 4 mm and/or domus to neck ratio < 1.5). Fifty aneurysms were small (<12 mm), 30 were large (12 to 25 mm) and 4 were giant (> 25 mm). Thirty four aneurysms were incidental, 10 were ruptured and 10 were recanalized after coil treatment and the majority was located in the internal carotid artery (76). Angiographic follow-up was done at the end of the procedure, at six month and at 18 month (controls I, II and III respectively), analyzing the rate of complete occlusion, recanalization and clinical complication. Statically analysis were done by Kaplan-Meier method for cumulative percentage of complete aneurysm occlusion and for recanalization, and univariate and multivariate analysis of predictive factors of immediate and late complete occlusion through logistic regression. Results: Complete aneurysm occlusion was achieved in 65.5% on immediate control, in 84.6% at 6 month, and in 90.3% at 18 month follow-up periods for all aneurysms. This rate was 74%, 95.1% and 95.2% for small and 53.3%, 70% and 80% for large aneurysms at the same follow-up periods. In the giant aneurysm group, two had complete and stable occlusion at six month follow-up angiography. Recanalization was seen in three aneurysms (4,6%). Kaplan Meyer\'s cumulative percentage of complete aneurysm occlusion was 97.63% (CI 95% ranging from 95,27 to 100) for small aneurysms at 9 months and 83.86% (CI 95% ranging from 67,73 to 100) for large aneurysms at 21 months. There were three deaths (4,3%), two procedure-related (2.9%). Overall morbidity was 7.2%, being disabling in one (1,4%). Conclusions: 1. The use of Onyx was efficient in the complete occlusion of wide neck intracranial aneurysms. 2. The treatment was stable at 6 month and 18 month angiographic controls.

Aspectos morfológicos do nido e embolização parcial neoadjuvante sem intenção de cura de malformações arteriovenosas encefálicas, precedendo a radiocirurgia, podem ter influência no resultado final do tratamento. Métodos: série consecutiva de 47 pacientes submetidos à radiocirurgia (1 a 5 sessões), precedida ou não por embolização com cianoacrilato. Acompanhamento clínico e radiológico mínimo de 36 meses. Resultados: a apresentação hemorrágica ocorreu em 68,1% dos pacientes tratados; destes, 62,5% portavam fístula arteriovenosa dentro da malformação arteriovenosa; 83,3% ectasia venosa e 90% restrição à drenagem venosa. A taxa de oclusão de embolização seguida de radiocirurgia foi de 46,1% e da radiocirurgia isolada foi de 52,4% (p=0,671). Foram identificados como fatores favoráveis à oclusão: baixo volume nidal, ausência de fístula arteriovenosa intranidal, maior dose de radiação e baixo grau na classificação das malformações arteriovenosas encefálicas baseadas na radiocirurgia (RBAS). Conclusões: o menor volume nidal (p < 0,001), o menor grau na escala RBAS (p=0,047), a ausência de fístula arteriovenosa intranidal (p=0,001) e a maior dose prescrita (p=0,001) tiveram correlação com resultado favorável no tratamento. Embolização seguida de radiocirurgia não foi superior à radiocirurgia isolada (p=0,772). A eliminação de fístulas arteriovenosas intranidais pela embolização pode aumentar a eficácia da radiocirurgia / Partial nidal embolization preceding radiosurgery of brain arteriovenous malformations (AVM) and some morphological nidal features may be related to final results. Methods: Analysis of a longitudinal cohort of 47 consecutive patients who underwent radiosurgery preceded or not by embolization. Embolizations were performed exclusively with n-butyl cyanoacrylate. Radiosurgery was delivered either as a single or divided up to 5 equal fractions. Clinical and radiological follow up of at least 36 months was obtained. Results: Hemorrhagic presentation was seen in 68.1% of the cases; 62.5% harbored intranidal arteriovenous fistulas (AVF), 83.3% had venous ectasias and 90% had venous outflow stenosis. The occlusion rate of embolization plus radiosurgery was 46.1% and radiosurgery alone was 52.4% (p = 0.671). Variables significantly associated with obliteration were lower nidus volume, lack of intranidal arteriovenous fistula, higher radiosurgical dose and lower grades in radiosurgical-based AVM scale (RBAS). Conclusions: a small nidus (p < 0.001), a lower RBAS grade (p = 0.047), no intranidal AVF (p = 0.001) and greater radiosurgical dose (p = 0.001) were associated to better results. Embolization followed by radiosurgery was not superior to radiosurgery alone (p = 0.772). Endovascular elimination of intranidal AVF\'s may help to promote radiosurgical occlusion

O trauma pélvico apresenta alta morbi-mortalidade, especialmente nos casos de dupla ruptura do anel pélvico (AP), devido à hemorragia. O objetivo deste trabalho é observar o tempo transcorrido até a realização do tratamento endovascular (TE), a sua eficácia e a estratégia de exames complementares empregado. 53 pacientes com fratura de bacia póstraumática foram submetidos a embolização arterial num estudo retro e prospectivo, realizado no período de janeiro de 2000 e dezembro de 2005. A idade dos pacientes variou entre 93 e 17 anos, com média de 37,5 anos. Houve predomínio do sexo masculino, com cerca de 62,2%. A causa do trauma mais freqüente foi o acidente de moto em 36% dos casos. Predominaram as fraturas com dupla ruptura do AP em 71,6 % dos casos. 49 pacientes apresentavam instabilidade hemodinâmica, e desses, todos receberam derivados sanguíneos previamente à realização do TE. Neste estudo 38,7% (n = 19) dos pacientes instáveis foram submetidos ao exame de tomografia computadorizada (TC) antes do TE, o tempo médio desse grupo para atingir a sala de radiologia vascular foi de 230,45 minutos. Nos pacientes enviados diretamente à arteriografia com intenção terapêutica, o tempo médio até início da realização do tratamento foi de 146,77 minutos. A diferença entre as taxas de mortalidade precoce nos grupos de pacientes submetidos ou não a TC previamente ao TE foi de 5,63%. O choque hemorrágico foi à causa de óbito em 63,33% dos pacientes que apresentaram mortalidade precoce. Na conduta inicial desses pacientes preconiza-se realizar o menor número de intervenções até o controle da hemorragia. O tempo transcorrido até a chegada na sala de radiologia vascular é fator importante no prognóstico dos pacientes com fraturas hemorrágicas da bacia. O TE precoce é uma importante ferramenta nos pacientes hemodinamicamente instáveis inicialmente / Pelvic trauma presents high morbi-mortality specially in cases of double rupture of pelvic ring due to hemorrhages. The objective of this work is to observe the time period since the rupture till the execution of endovascular treatment (ET) as well as the effectiveness and strategy for the used complementary exam. 53 patients with pos-traumatic pelvic fracture were submitted to arterial embolization during retro and prospective study. Such study was executed during the period of January 2000 to December 2005. The age of the patients varied between 17 and 93 years old, average 37.5 year old and predominantly men at about 62.2% of the cases. The most frequent cause of the traumas, 36%, was motorcycle accident. Predominantly fractures with double rupture of the pelvic ring, that is 71.6% of the cases. 49 patients presented hemodynamic instability, all of them received blood derivatives previously to the ET execution. In this study 38.7% (n=19) of the unstable patients were submitted to computerized tomography exam (CT) before the ET. The average period of time for this group to reach the room of vascular radiology was 230.45 min. For patients sent straight to arteriography with therapeutic intention, the average period time was 146.77 min. The difference, between the early mortality rate of the group undertaken or not to the CT previously to the ET, was 5.63%. The hemorrhagic shock was the cause of death in 63.33% patients, who presented early mortality. For the initial on going study of these patients, we recommend to accomplish the least number of interventions until hemorrhage is controlled. The elapsed time till the arrival at the vascular radiology room is an important factor to make prognosis about patients with hemorrhagic pelvic fractures. The early ET is an important tool for patients with hemodynamic instability

Introdução: O risco do tratamento das malformações arteriovenosas encefálicas (MAVEs) é proporcional à sua graduação. O processo de seleção da técnica empregada depende, além da natureza e localização das MAVEs, das condições clínicas e idade dos doentes e da disponibilidade de profissionais treinados e de equipamentos apropriados no ambiente onde o doente é tratado. Objetivo: Avaliar a eficácia da radiocirurgia e da embolização prévia ao tratamento radiocirúrgico das MAVEs classificadas como graus 3A, 3B, 4 ou 5. Métodos e Resultados: O trabalho baseou-se na observação retrospectiva de prontuários clínicos e de arquivos de imagens de 90 doentes com diagnóstico de MAVEs classificadas como graus 3A, 3B, 4 ou 5 submetidos a tratamento com radiocirurgia precedida ou não de embolização no Departamento de Radioterapia e Radioterapia Estereotáctica, Neuroradiologia Intervencionista e Neurocirugia da Real e Benemérita Associação Portuguesa de Beneficência de São Paulo, de outubro de 1993 a outubro de 2008. As idades dos doentes variaram de sete a 60 anos (média de 30,6 anos ± 11,59 anos, mediana de 28 anos). Eram do sexo feminino 46 (51,1%) doentes. Todos foram submetidos a três exames de ressonância magnética (RM) ou tomografia computadorizada (TC) no primeiro ano de acompanhamento e a um exame de RM ou TC do encéfalo no segundo e terceiro anos. Quando um dos exames sugeriu oclusão da MAVE ou o período de acompanhamento foi maior que três anos, os doentes foram submetidos à angiografia digital do encéfalo. Em 51 (56,7%) dos 90 doentes tratados ocorreu oclusão completa da MAVE após a primeira radiocirurgia (1ª Rc), em 21 (23,3%) foram evidenciadas complicações clínica em 36 (40,0%), foram visibilizadas anormalidades no exame de RM. Em 30 (33,3%) doentes evidenciou-se hipersinal no encéfalo em T2 na RM xvi e, em seis (6,7%), radionecrose. Trinta e dois(82,0%) dos 39 doentes que não apresentaram oclusão completa da MAVE após a 1ª Rc foram submetidos à segunda radiocirurgia (2ª Rc). Ocorreu oclusão completa em 12 (37,5%) destes doentes, instalaram-se complicações clínicas em cinco (15,6%) e, anormalidades no exame de RM em oito (25,0%), ou seja, hipersinal em T2 na RM em três (9,5%) e radionecrose em cinco (15,6%). Conclusão: Concluiu-se que a radiocirurgia foi eficaz no tratamento das MAVEs graus 3A, 3B, 4 e 5, que as MAVEs classificadas como grau 3B devem tratadas, preferencialmente, apenas com radiocirurgia e que as MAVEs classificadas como 3A, 4 e 5 devem ser submetidas à embolização previamente à radiocirugia para reduzir-se sua graduação e seu fluxo sanguíneo / Introduction: The risk of treatment of the cerebral arteriovenous malformations (AVM) is proportional to their grade and is affected by the method used. The selection of the AVM therapeutic method depends of the vascular pattern and anatomical site, clinical condition and age of the patient, experience of the treating team and of the equipment available. Objectives: This study aimed the evaluation of the efficacy of the radiosurgical treatment of Grade 3A, 3B, 4 and 5 cerebral AVMs in patients previosly treated or not with embolization. Methods and Results: The data of the clinical notes and the computed tomography (CT) and magnetic ressonance (RM) images of the brain of 90 patients with Grade 3A, 3B, 4 or 5 cerebral embolised or not AVMs treated with radiosurgery at the Department of Radiotherapy, Stereotactic Radiotherapy, Interventional Neuroradiology and Neurosurgery at Real e Benemerita Associação Portuguesa de Beneficência de São Paulo were retrospectively reviewed. The ages of the patients ranged from 7 to 60 years of (average = 30.6 ± 11.59 years; median = 28 years) and 46 (51.1%) were female. During the first year after treatment three MR or CT scans of the brain were evaluated and one at the end of the 2nd and 3rd years after the treatment one MR or CT scan were re-evaluated respectively. When the brain scans suggest AVM occlusion, cerebral angiography was performed. In 51 of the 90 patients (56.7%) there was complete occlusion of the AVM after one radiosurgical treatment; 21 of the patients (23.3%) had clinical complications. In 36 patients (40.0%) new abnormalities of the MR became evident. Thirty (33.3%) presented T2 hypersignal and six (6.7%), had radionecrosis. From the 39 patients who did not had complete occlusion of the AVM, 32 (82.0%) had a second radiosurgical course of treatment; in 12 xviii (37.5%) the AVM became completely occluded but five (15.6%) had clinical complications. Eight (25.0%) of these patients presented new abnormalities at the MR scan of the brain; three (9.5%) had T2 hypersignal and five (15.6%) radionecrosis. Conclusions: Radiosurgery was effective in the treatment of Grade 3A, 3B, 4 and 5 cerebral AVMs , Grade 3B cerebral AVM should be treated only with radiosurgery without previous embolization, and Grade 3A, 4 and 5 AVMs should be treated with embolization to reduce their AVM grade and blood flow prior to radiosurgery

<p>Transcatheter Arterial Embolization (TAE) is a method in which a catheter is inserted into an artery under fluoroscopy guidance. By using material that creates a thrombus, inserted through the catheter, the artery can be occluded and the bleeding stopped.</p><p>Endoscopy is the treatment of choice in upper gastrointestinal (GI) bleeding, but 10% to 30% of patients rebleed and needs other treatment options. Post Partum Hemorrhage (PPH) may evolve rapidly and can become life threatening. Obstetrical treatment will manage most cases, but in some cases emergency surgery is needed and in the worst case hysterectomy.</p><p>The primary aim of this thesis was to evaluate the clinical usefulness, improve the TAE technique and compare the outcome of TAE with surgery used as “salvage therapy” in patients with upper GI bleeding. Evaluate TAE technique and the long-term effect on the menstrual cycle and fertility in severe PPH.</p><p>To evaluate the clinical usefulness 13 patients were treated with TAE after endoscopic treatment failure and 5 were treated for recurrent hemorrhage after emergency surgery. </p><p>The clinical outcome and mortality rate of 40 patients treated with TAE was compared with 51 patients treated with surgery of upper GI bleedings. </p><p>In 13 patients the ulcer was marked with placement of a metallic clip at endoscopy to be able to locate the exact site of the bleeding ulcer during the TAE procedure.</p><p>A retrospective study of 20 patients with severe PPH treated with bilateral TAE of the uterine artery was performed. </p><p>TAE was found to be effective and an alternative to emergency surgery for control of massive upper GI bleeding. The 30-day mortality was lower in the TAE group (3%) compared to the surgical group (14%). </p><p>By marking the bleeding ulcer at endoscopy using a metallic clip the site of bleeding could be identified on angiography without extravasation of contrast media.</p><p>No major impact on fertility or menstruation cycle was found in patients treated with TAE in PPH. TAE in PPH is safe and have no major long-term side effect. By using TAE in PPH hysterectomy can be avoided.</p>

Transcatheter Arterial Embolization (TAE) is a method in which a catheter is inserted into an artery under fluoroscopy guidance. By using material that creates a thrombus, inserted through the catheter, the artery can be occluded and the bleeding stopped. Endoscopy is the treatment of choice in upper gastrointestinal (GI) bleeding, but 10% to 30% of patients rebleed and needs other treatment options. Post Partum Hemorrhage (PPH) may evolve rapidly and can become life threatening. Obstetrical treatment will manage most cases, but in some cases emergency surgery is needed and in the worst case hysterectomy. The primary aim of this thesis was to evaluate the clinical usefulness, improve the TAE technique and compare the outcome of TAE with surgery used as “salvage therapy” in patients with upper GI bleeding. Evaluate TAE technique and the long-term effect on the menstrual cycle and fertility in severe PPH. To evaluate the clinical usefulness 13 patients were treated with TAE after endoscopic treatment failure and 5 were treated for recurrent hemorrhage after emergency surgery. The clinical outcome and mortality rate of 40 patients treated with TAE was compared with 51 patients treated with surgery of upper GI bleedings. In 13 patients the ulcer was marked with placement of a metallic clip at endoscopy to be able to locate the exact site of the bleeding ulcer during the TAE procedure. A retrospective study of 20 patients with severe PPH treated with bilateral TAE of the uterine artery was performed. TAE was found to be effective and an alternative to emergency surgery for control of massive upper GI bleeding. The 30-day mortality was lower in the TAE group (3%) compared to the surgical group (14%). By marking the bleeding ulcer at endoscopy using a metallic clip the site of bleeding could be identified on angiography without extravasation of contrast media. No major impact on fertility or menstruation cycle was found in patients treated with TAE in PPH. TAE in PPH is safe and have no major long-term side effect. By using TAE in PPH hysterectomy can be avoided.

Electroporation is the critical step in an electric field mediated drug or gene delivery protocol. Electroporation based protocols have been successfully demonstrated in cancer clinical trials, however, its impact in other applications is still under investigation. A significant roadblock to long term functioning of implantable biosensors in vivo is the tissue reaction in the form of fibrous encapsulation that results in reduced transport to the sensing element of the biosensor. In vivo gene electroporation has a great potential as a means to modify the transport properties of tissues in the proximity of the sensing element of implantable biosensors. This dissertation examines two postulated electroporation based strategies to modify tissue for enhanced performance of an implantable biosensor. In the first, the implantation protocol is modified to accommodate in vivo electroporation. In the second strategy, the the modification is applied post implantation. This post-implantation in vivo electroporation application requires that electric energy be delivered at the site of electroporation close to the biosensor while minimizing effects far from such site. A novel method, focusing electric fields, developed for this purpose is presented. A theoretical framework as well as in vitro and in vivo experiments are provided as the introduction to the method and in support of its potential as the basis of a viable technology.

Aspectos morfológicos do nido e embolização parcial neoadjuvante sem intenção de cura de malformações arteriovenosas encefálicas, precedendo a radiocirurgia, podem ter influência no resultado final do tratamento. Métodos: série consecutiva de 47 pacientes submetidos à radiocirurgia (1 a 5 sessões), precedida ou não por embolização com cianoacrilato. Acompanhamento clínico e radiológico mínimo de 36 meses. Resultados: a apresentação hemorrágica ocorreu em 68,1% dos pacientes tratados; destes, 62,5% portavam fístula arteriovenosa dentro da malformação arteriovenosa; 83,3% ectasia venosa e 90% restrição à drenagem venosa. A taxa de oclusão de embolização seguida de radiocirurgia foi de 46,1% e da radiocirurgia isolada foi de 52,4% (p=0,671). Foram identificados como fatores favoráveis à oclusão: baixo volume nidal, ausência de fístula arteriovenosa intranidal, maior dose de radiação e baixo grau na classificação das malformações arteriovenosas encefálicas baseadas na radiocirurgia (RBAS). Conclusões: o menor volume nidal (p < 0,001), o menor grau na escala RBAS (p=0,047), a ausência de fístula arteriovenosa intranidal (p=0,001) e a maior dose prescrita (p=0,001) tiveram correlação com resultado favorável no tratamento. Embolização seguida de radiocirurgia não foi superior à radiocirurgia isolada (p=0,772). A eliminação de fístulas arteriovenosas intranidais pela embolização pode aumentar a eficácia da radiocirurgia / Partial nidal embolization preceding radiosurgery of brain arteriovenous malformations (AVM) and some morphological nidal features may be related to final results. Methods: Analysis of a longitudinal cohort of 47 consecutive patients who underwent radiosurgery preceded or not by embolization. Embolizations were performed exclusively with n-butyl cyanoacrylate. Radiosurgery was delivered either as a single or divided up to 5 equal fractions. Clinical and radiological follow up of at least 36 months was obtained. Results: Hemorrhagic presentation was seen in 68.1% of the cases; 62.5% harbored intranidal arteriovenous fistulas (AVF), 83.3% had venous ectasias and 90% had venous outflow stenosis. The occlusion rate of embolization plus radiosurgery was 46.1% and radiosurgery alone was 52.4% (p = 0.671). Variables significantly associated with obliteration were lower nidus volume, lack of intranidal arteriovenous fistula, higher radiosurgical dose and lower grades in radiosurgical-based AVM scale (RBAS). Conclusions: a small nidus (p < 0.001), a lower RBAS grade (p = 0.047), no intranidal AVF (p = 0.001) and greater radiosurgical dose (p = 0.001) were associated to better results. Embolization followed by radiosurgery was not superior to radiosurgery alone (p = 0.772). Endovascular elimination of intranidal AVF\'s may help to promote radiosurgical occlusion