Treatment of a Fusiform Anterior Cerebral Artery Aneurysm by Remodeling the Circle of Willis with Flow Diversion: A Novel Technical Note

Abstract

Fusiform aneurysms are challenging lesions to manage given their poorly understood natural history and lack of a distinct neck. Historically, they have been treated surgically but endovascular management has recently evolved as a viable alternative. In this case, we describe a novel flow diversion technique for treatment of a fusiform anterior cerebral artery (ACA) aneurysm by jailing the compromised parent vessel obtaining endovascular aneurysm trapping. A 25-year-old man underwent brain magnetic resonance imaging and magnetic resonance angiography for workup of a headache, which revealed a fusiform right ACA A1 segment aneurysm. The patient subsequently underwent catheter digital subtraction angiography, which confirmed a 9× 5.5 mm fusiform right ACA A1 segment aneurysm. The patient elected to undergo endovascular treatment. A Pipeline Embolization Device (Medtronic, Dublin, Ireland) was placed from the right anterior cerebral artery to the right middle cerebral artery, thereby jailing the right ACA A1 segment. At 6-month follow-up, the patient was asymptomatic and his headache had resolved. An angiogram was obtained, showing patency of the Pipeline Embolization Device and near complete occlusion of the right ACA A1 segment. The right ACA A2 segment remained patent via collateral flow through the anterior communicating artery. These findings were confirmed on magnetic resonance imaging. The patient remained asymptomatic for the duration of the follow-up. This case illustrates the efficacy of the Pipeline Embolization Device for treatment of a fusiform anterior circulation aneurysm via remodeling the circle of Willis.