両側対称性中大脳動脈瘤に正中深部脳動静脈奇形を合併した1例

A Case of Symmetrical Aneurysms at the Bilateral Middle Cerebral Arteries Associated with the Deep Seated Arteriovenous Malfomation in the Midline

　くも膜下出血で発症した両側対称性中大脳動脈瘤に正中深部脳動静脈奇形を合併した1例を報告した。過去にこのような報告はなく，極めて稀と思われた。その成因として，脳動静脈奇形の発生過誤期に脳動脈瘤が同時に発生したものと推測され，嚢状脳動脈瘤の成因が高血圧症，hemodynamic stressなどの後天性要因だけではなく，先天性要因の関与も考える上で重要な症例と思われた。

A case of symmetrical aneurysms at the bilateral middle cerebral arteries (MCA) associated with the deep seated arteriovenous malfomation (AVM) in the midline was presented. Because symmetrical aneu-rysms at the MCA are 1.17% of all aneurysms, and those associated with the deep seated AVM in the midline are very rare.

A 75-year-old female suffered from a sudden onset of a severe headache and a loss of consciousness, and was admitted to our department on June 14, 1996. Computed tomography (CT) showed a subarachnoid hemorrhage (SAH) in the right sylvian fissure (Fisher's Group 4).