後下小脳動脈末梢部に発生した多発性脳動脈瘤の1例

A Case of Multiple Aneurysms at the Distal Portion of the Posterior Inferior Cerebellar Artery

I．はじめに

　椎骨脳底動脈系における動脈瘤の発生頻度は全脳動脈瘤の3-10％程度といわれており，なかでも頻度の高い部位は，脳底動脈分岐部，後大脳動脈，椎骨後下小脳動脈分岐部などである．一方，後下小脳動脈末稍部の動脈瘤になるとその頻度は少なく，さらに同部の多発性のものになると，その頻度は極めて少ない．

　最近われわれは，後下小脳動脈末梢部に多発した動脈瘤を経験したので，若干の考察を加え報告する．

We present a case of multiple aneurysms of theposterior inferior cerebellar artery (PICA) at the distalportion, which is very rare.

A 62-year-old woman was admitted to our hospitalwith complaint of a severe headache. Four-vesselstudy was carried out and we found one aneurysm inthe retromedullary segment of the right PICA. Theaneurysm was clipped through the median subocci-pital approach. But postoperative angiography show-ed that aneurysm was not being clipped and the clipwas seen about 1 cm proximal to the aneurysm. Weconcluded that she had two aneurysms and the secondoperation was performed.