Long-term outcome following anterior cerebral artery ligation for ruptured anterior communicating artery aneurysms. The long-term prognosis (15 years) was determined for 17 patients who had undergone anterior cerebral artery (ACA) ligation as the sole treatment for an anterior communicating artery aneurysm. The number of early and late rebleeds was lower than expected from previously ruptured aneurysms. Late ischemia was not a major complication while late postoperative epilepsy occurred in 19% of survivors. In a review of previously published series, ACA ligation appears to have significantly reduced the rates of both early and late rebleeding. This study helps to define the late results of "conservative" operations for ruptured aneurysms. 