Extracranial-intracranial bypass and vessel occlusion for the treatment of unclippable giant middle cerebral artery aneurysms.

BACKGROUND: Giant middle cerebral artery (MCA) aneurysms pose management challenges.

OBJECTIVE: To review the outcomes of patients with giant MCA aneurysms not amenable to clipping or vessel reconstruction treated with extracranial-intracranial (EC-IC) bypass and vessel sacrifice.

METHODS: We retrospectively reviewed a database of aneurysms treated at our institution between 1983 and 2011.

RESULTS: Sixteen patients (11 males, 5 females) were identified. There were 10 saccular, 4 fusiform, and 2 serpentine aneurysms. The aneurysms predominantly involved the M1 segment in 5 cases, M2 in 9 cases, and both M1 and M2 in 2 cases. The EC-IC bypasses performed included 13 superficial temporal artery-MCA, 1 saphenous vein graft-MCA, and 2 radial artery grafts-MCA. The postoperative bypass patency rate was 93.8% (15/16). There were 3 cerebrovascular accidents (18.8%), but no perioperative deaths (0% mortality). The mean follow-up was 58.4 months (range, 1-265; median, 23.5 months). In 75% (12/16) of cases the aneurysms were occluded successfully. A small residual was noted in 3 cases with the use of this treatment strategy, and they were re-treated. In a fourth case treated with partial distal occlusion, reduced flow through the aneurysm was noted postoperatively, but the patient did not undergo further treatment. The mean modified Rankin scale and mean Glasgow Outcome Scale scores at last follow-up were 1.6 (range, 1-4; median, 1) and 4.8 (range, 3-5; median, 5), respectively.

CONCLUSION: Giant MCA aneurysms are challenging lesions. EC-IC bypass with parent vessel occlusion can provide a durable form of treatment with acceptable rates of morbidity and mortality.