Prevention of Rebleeding after Operation for Subarachnoid Hemorrhage of Unknown Cause

Abstract

Abstract This study is presented to promote prophylactic operation to prevent rebleeding after subarachnoid hemorrhage (SAH) of unknown cause. Twenty-two cases of nontraumatic SAH of unknown cause of a total of 254 cases of SAH treated during a 5-year period (1980-1984) were available for this study. A follow-up study (4 to 61 months after treatment; median, 43 months) revealed a 4.5% mortality rate. Four patients chosen from among the 22 SAH cases underwent prophylactic operation. The decision to operate was based on repeated angiography showing regional cerebral vasospasm corresponding to a limited hyperdense area on the computed tomographic scan at the time of the onset of SAH. Microsurgery revealed a minute protrusion (less than 2 mm in diameter) or thinning of the arterial wall with old hematoma of the surrounding brain in all 4 cases, and treatment required only coating of the abnormal site. All 4 patients are now fully recovered. Frequently, abnormal changes of such cerebral arteries as the anterior communicating artery, the internal carotid artery (C-1 and C-2), and the middle cerebral artery (M-1) may occur. Therefore, the authors emphasize the necessity of surgical treatment for specific cases of SAH with an unknown cause.