後下小脳動脈末梢部から発生した偽性動脈瘤の1例

A Case of a Ruptured Pseudoaneurysm Arising from the Distal Part of the Posterior Inferior Cerebellar Artery

Ⅰ．はじめに

　後下小脳動脈posterior inferior cerebellar artery（PICA）の走行は小脳動脈の中でも最も変化に富み，種々の部位に動脈瘤が発生するといわれている．今回われわれは脳室内出血で発症した末梢性後下小脳動脈瘤の興味深い1例を経験したので，文献的考察を加えて報告する．

We report a rare case of a pseudoaneurysm arising from the distal part of the posterior inferior cerebellar artery (PICA) and which was associated with intraventricular hemorrhages. A 48-year-old female had sudden onset of severe headache and vomiting, and was admitted in a semicomatous state to our hospital. Initial CT scan showed ventricular hematomas resulting in acute hydrocephalus, but no obvious parenchymal or subarachnoid hemorrhage. Ventricular drainage was carried out. Subsequently, cerebral angiography was performed, but neither, an aneurysm nor other vascular abnormality was detected.