Management of anterior inferior cerebellar artery aneurysms: an illustrative case and review of literature.

Aneurysms of the anterior inferior cerebellar artery (AICA) are relatively rare among intracranial aneurysms. They can occur in 1 of 3 regions of the AICA: 1) craniocaudal (high or low riding), 2) mediolateral-premeatal (proximal), and 3) meatal-postmeatal (distal). The management strategies for treatment differ according to the location and configuration of the aneurysm. The existing body of neurosurgical literature contains articles published on aneurysms arising from the AICA near the basilar artery (BA), intracanalicular/meatal aneurysms, and distal AICA. Several therapeutic options exist, encompassing microsurgical and endovascular techniques. The authors describe a case of treatment involving a large BA-AICA aneurysm approached via exposure of the presigmoid dura using a retromastoid suboccipital craniectomy and partial petrosectomy. Treatment of these lesions requires detailed knowledge of the anatomy, and an anatomical overview of the AICA with its arterial loops and significant branches is presented, including a discussion of the internal auditory (labyrinthine) artery, recurrent perforating arteries, subarcuate artery, and cerebellosubarcuate artery. The authors discuss the various surgical approaches (retromastoid, far lateral, subtemporal, and transclival) with appropriate illustrations, citing the advantages and disadvantages in accessing these AICA lesions in relation to these approaches. The complications of these different surgical techniques and possible clinical effects of parent artery occlusion during AICA surgery are highlighted.