1141. Microsurgical Treatment of Cerebral Aneurysms after prior Endovascular Therapy: Single Center Series and Systematic Review

Authors: Anil Kumar Roy, MD; Lucas Phillip, MD; Brian Howard, MD; Charles Cawley, MD; Jonathan Grossberg, MD; Daniel Barrow, MD (Atlanta, GA)

Introduction: Since its introduction in the early 90s, endovascular treatment of cerebral aneurysms has had a steady upward trend and is currently the primary mode of treatment for most intracranial aneurysms. Concurrently, the need for retreatment of aneurysms after prior endovascular treatment has continued to grow, some of which can only be treated with microsurgical techniques. The factors that dictate outcomes in this group of patients are incompletely understood. Methods: The senior author’s records since 2002 were retrospectively reviewed for aneurysms treated after prior endovascular treatment. Demographics, treatment details and imaging were reviewed for all patients. A systematic review of the literature on microsurgical treatment of aneurysms previously treated by endovascular therapy was also conducted. Results: A total of 91 patients were identified from the review. Mean age at the time of initial treatment was 49 ± 12.68 years. Most patients initially presented with subarachnoid hemorrhage prior to initial endovascular treatment, with only 11 (12%) patients presenting with incidentally discovered lesions. mRS at discharge after initial treatment was good (0-3) in 81.4% of cases. Functional outcomes at the last known follow-up revealed a mRS of 0-3 in 74 (81.3%) patients. Only aneurysm neck size was found to be a significant predictor of surgical complications (Wald χ 2 =10.79, p=0.0010) with an odds ratio of 2.32 (95% CI: 1.40 , 3.83) for a 2mm increase in neck size. Systematic review identified 37 studies that were used to pool data on 370 total patients. Although type of surgery was identified as a predictor of poor outcomes this was significantly confounded by Hunt and Hess grade in the systematic review. Conclusion: Favorable outcomes can be obtained even for highly complex cerebral aneurysms that have failed endovascular treatment at high volume cerebrovascular centers. Initial presentation grade and aneurysm size are important predictors of final outcomes.