Aneurysms of the Proximal Segment of the Middle Cerebral Artery

Kang, Myung Sang; Park, In Sung; Lee, Chul Hee; Hwang, Soo Hyun; Jung, Jin Myung; Han, Jong Woo

Abstract

OBJECTIVE
he aim of this study is to analyse the clinical characteristics of aneurysms of the proximal middle cerebral artery (M1 segment) and to compare our results with literatures. METHODS: From January 1990 to July 2002, fifteen(2%) of 750 operated aneurysm patients had M1 segment aneurysm. All patients underwent surgery via medial-to-lateral sylvian approach. Preoperative clinical and radiological characteristics and surgical outcome were analysed. RESULTS: All 15 patients presented with subarachnoid hemorrhage and 13 patients had ruptured M1 aneurysm. Of the 15 patients, 6 were men and 9 were women. The incidence of multiple aneurysms was high(five patients, 33%). Among 5 patients of multiple aneurysms, M1 aneurysm was ruptured in 3 patients. On cerebral angiogram and intraoperative finding, there were 9 cases with superior wall type aneurysm and 6 cases with inferior wall type aneurysm. Preoperative rebleeding was developed in 5 patients(33%) and mostly in inferior wall type. Seven patients had intracerebral hematoma. Of eight M1 aneurysms greater than 5mm in diameter, 7(86%) ruptured and 6 (86%) of seven small (< or =5mm) aneurysms ruptured. Postoperatively, twelve patients of 15 patients made a useful recovery and 3 patients died of initial insult and rebleeding. CONCLUSION: To achieve good outcome, the authors suggest that special attention to preventing preoperative rebleeding and early microneurosurgery are critical for successful surgical treatment of the proximal MCA aneurysm due to high incidence of rebleeding and rupture of small aneurysm.