Review of treatment modalities and clinical outcome of giant saccular anterior inferior cerebellar artery aneurysms

INTRODUCTION: Giant anterior inferior cerebellar artery (AICA) aneurysms are rare lesions carrying significant morbidity due to mass effect and present therapeutic challenges due to proximity to critical neurovascular structures. MATERIALS AND METHODS: A systematic literature review through the PubMed and Scopus databases was performed according to the PRISMA guidelines to identify cases of giant saccular AICA aneurysms treated either microsurgically or by endovascular means. Patients' demographics, aneurysm size, preoperative and postoperative neurologic status, clinical outcomes as well as follow-up information were retrieved. RESULTS: Data from 5 studies including 5 patients was obtained. Mean patient age was 36.6 years, with a male-to-female ratio of 4:1. Mean maximum aneurysm diameter was 31.1 mm. A favorable outcome (mRS 0-2) was reported on all cases. There were no reported deaths. The distal AICA was sacrificed in 40% of the patients without lasting morbidity. Three patients underwent microsurgery, one endovascular flow-diverter stenting and coiling, and one a combination of endovascular trapping and microsurgical debulking. All aneurysms were at least partially thrombosed, while 80% were debulked due to mass effect. CONCLUSIONS: Giant AICA aneurysms are amenable to both microsurgery and endovascular treatment. AICA sacrifice may be safely attempted in distal aneurysms. Proximal thrombosed aneurysms which cannot be safely embolized or ones with significant mass effect may benefit from microsurgical occlusion and may require debulking.