Outcome of surgical clipping for ruptured, low-grade, anterior circulation cerebral aneurysms: should clipping be omitted after International Subarachnoid Aneurysm Trial?

Abstract

Background A recent randomized trial for ruptured aneurysm resulted in poorer outcomes for the surgical group than the endovascular group. However, the surgical results seemed to be worse than could be expected for experienced neurosurgeons in Japan. We therefore analyzed our own surgical results and evaluated them for a comparison with the trial results. Methods Data on patients with ruptured, small, anterior circulation aneurysms in good clinical condition (World Federation of Neurological Surgeons grade I or II) and treated with surgical clipping were obtained from various discharge databases for 1997 to 2001, and their outcomes were analyzed in a retrograde fashion. Results Of the total of 487 patients, 17.6% showed a poor outcome (modified Rankin Scales 3-6) at discharge, and after 1 year, 6.1% remained in poor clinical condition. However, fewer patients were in poor condition both at discharge and after 1 year compared with the surgical and endovascular results for patients entered in the International Subarachnoid Aneurysm Trial. Complete occlusion of the aneurysm was attained in 93.6% of our patients. Rebleeding from the treated aneurysm occurred in 0.6%, and there was no rebleeding after 1 year. Conclusions Surgical clipping is a safe and reliable treatment and can be the first choice for small ruptured aneurysms of the anterior circulation with a good grade.