Saccular aneurysms of the distal anterior cerebral artery and its branches.

We report a series of 84 consecutive patients (41 women) with 92 distal anterior cerebral artery aneurysms (DACAA). All aneurysms were saccular. Four different locations of DACAAs were found: proximal, 5 aneurysms; frontobasal, 8; genu corporis callosi, 72; and distal, 7. Sixty-five patients presented with subarachnoid hemorrhage (SAH), the rest were incidental findings in patients with multiple aneurysms. Forty-five patients had single DACAAs. Multiple aneurysms (a total of 117) were found in 39 patients (46.4%), and DACAAs were responsible for SAH in 20 patients. Of the 65 patients with SAH, 54 underwent mainly early direct surgery, and 46 (85%) of these had good outcomes 1 year after surgery. Three patients remained severely disabled, and five patients (9%) died. All of the poor surgical results were obtained in patients with severe preoperative deficits. Exact measurements of DACAA sizes and necks were smaller than those of cerebral aneurysms in other locations. Aside from localization, microsurgery of these aneurysms presented no special difficulties, as compared with surgery of aneurysms in other locations.