Ischemic complications of surgery for anterior choroidal artery aneurysms

Object. Anterior choroidal artery (AChA) aneurysms account for 4% of all in tracranial aneurysms. The surgical approach is similar to that for other su praclinoid carotid artery lesions, but surgery may involve a higher risk of debilitating ischemic complications because of the critical territory supp lied by the AChA. Methods. Between 1968 and 1999, 51 AChA aneurysms in 50 patients were treat ed using craniotomy and clipping at the Mayo Clinic. There were 22 men (44% ) and 28 women (56%) whose average age was 53 years (range 27-79 years). Tw enty-four AChA aneurysms (47%) had hemorrhaged; nine patients (18%) had sub arachnoid hemorrhage from another aneurysm. Three AChA aneurysms (6%) were associated with symptoms other than rupture. Forty-one patients (82%) achie ved a Glasgow Outcome Scale (GOS) score of 4 or 5 at long-term follow up. T he surgical mortality rate was 4%, and major surgical morbidity (GOS less t han or equal to 3) was 10%. Eight patients (16%) had clinically and compute rized tomography-demonstrated AChA territory infarcts. Five of these stroke s manifested in a delayed fashion 6 to 36 hours after the operation, and pr ogressed from mild to complete deficit over hours. In 41 patients the aneur ysm arose from the internal carotid artery adjacent to the AChA, and in nin e patients the aneurysm arose directly from the origin of the AChA itself; four of these nine patients had postoperative infarction. Conclusions. Surgical treatment of AChA aneurysms involves a significant ri sk of debilitating ischemic complications. Most postoperative strokes occur in a delayed fashion, offering a potential therapeutic window. Patients wi th aneurysms arising from the AChA itself have an extremely high risk for p ostoperative stroke.