中大脳動脈解離性動脈瘤の1例

Dissecting Aneurysm of the Middle Cerebral Artery : case report

I．はじめに

　近年，頭蓋内解離性動脈瘤に対する関心が高まり，本邦を中心に多数の報告がなされている^9-11）．その多くは椎骨脳底動脈系の動脈瘤であるが，内頸動脈系についての報告は少なく^10,11），特に中大脳動脈解離性動脈瘤の報告は10例にも満たない^1-3,5-8）．今回，われわれは脳内出血で発症し，脳血管撮影，術中所見を経て確定診断に至った中大脳動脈解離性動脈瘤を経験したので文献的考察を加えて報告する．

We present a surgical case of a dissecting aneurysm of the right middle cerebral artery associated with subarachnoid hemorrhage and intracranial hemorrhage. A 61-year-old woman with consciousness distur-bance and left hemiplegia was referred to our hospital. She had suffered severe headache for a week. CTscan showed a subarachnoid hemorrhage in the right Sylvian fissure and intracranial hemorrhage in theright putamen. The right carotid angiogram revealed string sign in M₁ portion and occlusion at M₂ lowerbranch of the right middle cerebral artery. On the 12th day, we undertook surgery to confirm whether itwas a dissecting aneurysm or not. In the operation, it was reddish in the M, portion corresponding to the“string sign” arid dark-purplish in the lower M₂ portion corresponding to an “aneurysm-like lesion”. Toprevent bleeding, the arterial wall in the M, portion was coated using muscle. Though the left hemiplegiawas unchanged, the postoperative course was uneventful. The patient was transferred to another hospitaland underwent rehabilitation. There has been no reccurence during the four years since surgery. The mid-dle cerebral artery dissecting aneurysm is extremely rare. We presented this case with review of the litera-ture.