Microsurgical treatment for unruptured intracranial aneurysms: a modern single surgeon series

With the rise of endovascular treatments for the management of unruptured intracranial aneurysms (UIAs), advances in microsurgical techniques are underrepresented in modern surgical series, which largely consist of patients with aneurysms unfit for coiling. We report a modern series of microsurgical treatment for UIAs performed by a single surgeon as the preferred treatment modality. We retrospectively reviewed the charts of all patients with UIAs treated by the senior author with microsurgical clipping over an 11-year period. Procedure-related mortality, major neurologic morbidity (modified Rankin Score 3-5), complications, and persistent neurologic deficits were recorded. Risk factors for persistent neurologic deficits and major morbidity or mortality were analyzed using multivariate logistic regression analysis. We identified 329 patients with 400 UIAs treated in 353 surgeries. The average age was 52 years, 80% of patients were women, and 13% had a previous subarachnoid hemorrhage. The average aneurysm size was 7 mm and 92% were in the anterior circulation. The mean follow-up was 15 months (range 0.5-125). There was one procedure-related death (0.3%), and two patients suffered major morbidity (0.6%). Twenty procedures (5.6%) resulted in a persistent neurologic deficit. Risk factors for death and major morbidity were increasing age and posterior circulation, while risk factors for persistent neurologic deficits were increasing aneurysm size and posterior circulation. We conclude that microsurgical clipping is safe, effective, and should be given strong consideration as the primary treatment modality for younger patients with small to medium sized UIAs in the anterior circulation.