Ruptured Intrameatal Aneurysm of the Anterior Inferior Cerebellar Artery Accompanying an Arteriovenous Malformation: a Case Report

The distal anterior inferior cerebellar artery (AICA) aneurysms located inside the internal auditory canal are rare. The association of the distal AICA aneurysms and an arteriovenous malformation (AVM) on the same arterial trunk is exceptional. Eight reports of a total of ten cases have been published and all of the reported aneurysms were located in the meatal or postmeatal segment of the AICA. Herein, we report a case of ruptured aneurysm in the intrameatal portion of the AICA accompanying an AVM fed by the same artery. A 55-year-old man suffering from subarachnoid hemorrhage due to a ruptured intrameatal aneurysm with a small AVM underwent surgical trapping of the meatal loop, resulting in uneventful recovery. Follow-up angiography demonstrated neither aneurysm nor residual AVM nidus. We propose that trapping of the meatal loop could be a safe and feasible alternative to unroofing followed by neck clipping in selected patients with an intrameatal aneurysm of the AICA. We also review here the relevant literature.