上小脳動脈末梢部紡錘状動脈瘤の1例

A Case of Peripheral, Fusiform Type Aneurysm Originating from the Superior Cerebellar Artery

I．はじめに

　脳動脈瘤の中で上小脳動脈末梢部に発生するものは比較的まれで，47例が報告されているにすぎない^{1,4-6,8-10,13,14,16,19-21）}．その中でもfusiformtypeのものは極めてまれである．今回われわれは，くも膜下出血で発症したfusiform typeの上小脳動脈末梢部動脈瘤を急性期に手術し，良好な結果を得られたので報告するとともに，その発生機序について考察を加える．

We reported a case of a 33-year-old woman who presented a subarachnoid hemorrhage due to rupture ofan aneurysm arising from the ambient segment of the superior cerebellar artery (SCA). The patient whocomplained of severe headache and nausea was admitted on April 6, 1996. A CT scan revealed subarach-noid hemorrhage in the left cerebellopontine cistern. Left vertebral angiography showed a fusiform typeaneurysm of the ambient segment of the left SCA. Trapping of the aneurysm was successfully performedvia the subtemporal approach on the clay of admission, April 6, 1996. She was discharged with no deficitson May 2, 1996.

Fusiform type aneurysm arising from SCA is very rare. Only 3 cases have been reported in the litera-ture. We discussed the pathogenesis of this aneurysm and the timing of surgery.