脳動脈瘤根治術後, 他部位に動脈瘤の新生, 増大をみた6例の検討

抄録

In this paper, the authers report six cases of recurrence of SAH due to the rupture of newly developed or enlarged aneurysms which were not recognized during the previous aneurysmal operations.
Development of aneurysms from the dilatation at the origin of the posterior communicating artery was found in two patients, in whom carotid ligation had been performed previously for treatment of contralateral internal carotid aneurysms.
In three cases, newly developed aneurysms were revealed at the middle cerebral artery 6-10 years after operation for a contralateral middle cerebral artery aneurysm. In one of these cases the persistent primitive trigeminal artery was revealed by angiography; in the others small bulgings were found at the middle cerebral artery during the first aneurysmal operation.
Enlargement of a small unruptured aneurysm originally less than 2mm in diameter at the anterior communicating artery was found in one case, which had not been recognized during a previous operation for a ruptured middle cerebral artery aneurysm.
Hypertension was noted in all cases but one. Existance of a per-aneurysmal lesion or changes in the arterial wall due to hypertension, arteriosclerosis, etc., or hemodynamic stress caused by anomalies in the circle of Willis or previous carotid ligation seem to be responsible for the enlargement of existing aneurysms and the development of new ones. Our observations suggest that a preaneurysmal lesion of the cerebral artery may develop into an aneurysm and rupture, and hence control of hypertension or follow-up angiography is recommended for patients with preaneurysmal lesions or small aneurysms.