Distal anterior cerebral artery aneurysms: clinical features and surgical outcome.

Aneurysms of the distal anterior cerebral artery (DACA) are rare and their surgical treatments present some unique difficulties from a technical standpoint. In this report, we presented our experiences of cases with DACA aneurysms, and analyzed the clinical features and prognostic factors affecting the final outcomes. Among 770 cases of intracranial aneurysms operated from 1990 to 1998, 19 cases of DACA aneurysms (2.5%) were studied retrospectively. The characteristic findings were female preponderance (M:F = 1:2.8), common multiple aneurysms (57.9%), and frequent intracerebral hemorrhage (ICH) on initial brain CT scan (42.1%). All patients were operated via interhemispheric approach. Intraoperative aneurysmal rupture was developed only in 3 cases (15.8%), and had no relationship with the final outcome Fifteen out of 19 patients (78.9%) showed favorable outcome with a mortality rate of 5.3%. The follow-up data suggest that the initial ICH on brain CT scan portend a poor prognosis.