Peripheral large or giant fusiform middle cerebral artery aneurysms: report of our experience and review of literature.

Peripheral large and giant middle cerebral artery (MCA) aneurysms are rare and difficult to treat. We report our and others' experience with different possible modalities used to treat such lesions. Three patients were treated differently at our institution. One harboured a giant fusiform aneurysm on a peripheral branch of the superior trunk of the left MCA, and was treated by extracranial-intracranial (EC-IC) bypass and trapping of the aneurysm. The second patient was harbouring a large fusiform aneurysm on a peripheral branch of the inferior trunk of the right MCA, which was treated by trapping and excision without the need of an EC-IC bypass as assessed pre- and intraoperatively, while the last case was harbouring a giant fusiform aneurysm at the junction of M2-M3 and was treated by EC-IC bypass and end-to-end anastomosis after resection of the aneurysm. The aneurysms proved to be neither mycotic nor dissecting. The patients were clinically intact during their perioperative course without any postoperative complications and required no further treatment. Follow-up angiography demonstrated a functioning EC-IC bypass. Based on the surgical experience in these 3 cases and a review of the reported literature, the authors propose that when considering surgical treatment for such rarely encountered aneurysms, careful pre- and intraoperative evaluation including aneurysm trapping with or without EC-IC bypass when possible should be performed to obtain a satisfactory result without complication.