Aneurysm of the Fenestrated Basilar Artery: Case Report and Literature Review

Abstract

Introduction Aneurysms of the vertebrobasilar junction are rare, but when present, they are often associated with fenestration of the basilar artery. Frequently, the endovascular treatment is the first choice due to the complex anatomy of the posterior fossa, which represents a challenge for the open surgical treatment alternative.

Case Report A 47-year-old man was admitted to the emergency unit with headache, diplopia, neck pain and mental confusion. The neurological exam showed: score of 15 in the Glasgow coma scale (GCS), no motor or sensitivity deficit, palsy of the left sixth cranial nerve and Hunt-Hess grade III. The computed tomography (CT) scan showed subarachnoid hemorrhage (Fisher III) and hydrocephalus. The patient was submitted to ventricular-peritoneal shunt. A diagnostic angiography was performed with 3D reconstruction, which showed evidence of fenestration of the basilar artery associated with aneurysm in the right vertebrobasilar portion. An aneurysm coil embolization was performed without complications. The patient was discharged 19 days later maintaining diplopia, with paralysis of the left sixth cranial nerve, but without any other complaints or neurological symptoms.

Discussion Fenestration of the basilar artery occurs due to failure of fusion of the longitudinal neural arteries in the embryonic period, and it is associated with the formation of aneurysms. The endovascular treatment is the first choice and several techniques are described, including simple coiling, balloon remodeling, stent-assisted coiling, liquid embolic agents and flow diversion devices. The three-dimensional rotational angiography (3DRA) is an extremely helpful tool when planning the best treatment course.

Conclusion Fenestrated basilar artery aneurysms are rare and complex vascular diseases and their treatment improved with the advent of the 3D angiography and the development of the endovascular techniques.

Resumo

Introdução Aneurismas da junção vertebrobasilar são raros, mas quando presentes, geralmente estão associados à fenestração da artéria basilar. Frequentemente, o tratamento endovascular é a primeira opção devido à complexidade da anatomia da fossa posterior, o que representa um obstáculo para a alternativa de tratamento com cirurgia aberta.

Relato de Caso Um homem de 47 anos de idade deu entrada na unidade de emergência com cefaleia, diplopia, dor no pescoço e desorientação. O exame neurológico mostrou: 15 pontos na escala de coma Glasgow (ECG), ausência de déficit motor ou de sensibilidade, paralisia do sexto nervo craniano I esquerdo, Hunt-Hess grau III. A tomografia computadorizada apresentou hemorragia subaracnoidea (Fisher grau III) e hidrocefalia. O paciente foi submetido a shunt ventricular-peritoneal. A arteriografia diagnóstica foi feita com reconstrução 3D, que comprovou fenestração da artéria basilar associada a aneurisma na porção vertebrobasilar direita. Realizamos embolização do aneurisma com molas, sem complicações. O paciente recebeu alta 19 dias depois, mantendo diplopia, paralisia do sexto nervo craniano esquerdo, sem outras complicações ou sintomas neurológicos.

Discussão A fenestração da artéria basilar ocorre devido à falência da fusão das artérias neurais longitudinais no período embrionário e está associada à formação de aneurismas. O tratamento endovascular é a primeira opção e várias técnicas são descritas, incluindo simples embolização, remodelagem por balão, embolização assistida com stent, agentes embólicos líquidos e dispositivos de desvio de fluxo. Para planejar o melhor tratamento, angiografias rotacionais 3D são extremamente úteis.

Conclusão Aneurismas de artéria basilar fenestrada são doenças vasculares raras e complexas, e seu tratamento foi aprimorado com o advento de angiografias 3D e desenvolvimento de técnicas endovasculares.

Keywords

intracranial aneurism - subarachnoid hemorrhage - cerebral angiography - fenestration

Palavras-chave

aneurisma intracraniano - hemorragia subaracnoide - angiografia cerebral - fenestração

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