Fusiform intracranial aneurysms: long-term outcomes and treatment risks at a tertiary neuroscience centre

PURPOSE: Fusiform intracranial aneurysms (IA) are rare vascular lesions with limited data on natural history and management. We assessed long-term outcomes of fusiform IAs, including progression, rupture, and treatment-related morbidity. METHODS: We retrospectively studied all fusiform IAs diagnosed and managed at our institution between January 2010 and December 2021. Demographics, aneurysm features, clinical course, and treatment outcomes were analysed. Logistic regression identified predictors of progression and neurological complications. RESULTS: We identified 100 patients (median age 52.7 years; 53% female). At diagnosis, 73/100 were unruptured. Locations included the middle cerebral artery (30%), vertebral artery (17%), internal carotid artery (14%), and basilar artery (11%). Over a median 74-month follow-up, 9/73 (13%) of unruptured aneurysms progressed and 1/73 (1.4%) ruptured. 48 aneurysms were treated with flow diversion (36%), parent vessel occlusion (29%), stent-assisted coiling (23%), or surgery (12%). Aneurysm occlusion was achieved in 96% of imaged treated cases. Permanent neurological deficit occurred in 23% of treated patients. CONCLUSIONS: Treatment of fusiform IAs achieved high occlusion rates but carried substantially higher morbidity than typically reported for saccular aneurysms. Given the low rupture rate and modest progression risk, treatment may be best reserved for ruptured or progressing lesions.