Surgical Versus Endovascular Treatment of Middle Cerebral Artery Aneurysms: A Single-Center Retrospective Cohort Study Emphasizing Complex Lesions

BACKGROUND AND OBJECTIVES: Middle cerebral artery aneurysms, especially those with complex morphology, present significant treatment challenges and are commonly managed with either microsurgical treatment (MT) or endovascular treatment (EVT). This study compares clinical and angiographic outcomes for MT and EVT in a single-center retrospective cohort, with particular attention to aneurysm complexity. METHODS: We retrospectively reviewed 234 middle cerebral artery aneurysms treated between 2006 and 2024 with either MT clipping with and without bypass or wrapping, or with EVT, including coiling, stent-assisted or balloon-assisted coiling, and flow diversion. Outcomes, including modified Rankin Scale scores, occlusion rates, and complications, were assessed at discharge, 3 months, and at long-term follow-ups. Aneurysms were classified by rupture status and morphological complexity. RESULTS: Of 234 patients, 168 underwent MT and 66 received EVT. Baseline age and sex were similar, although ruptured and complex aneurysms were significantly more common in the surgical group (P < .01). Both groups achieved high rates of functional independence at 3 months (modified Rankin Scale 0-2: 93% vs 92%; P > .5). Rupture at presentation was the strongest predictor of unfavorable outcome (∼20-fold higher odds of 3-month mortality; P < .001). Intraprocedural rupture was more frequent with EVT (6.1% vs 0.6%; P = .02). MT achieved near-universal complete occlusion (98%), while only 18% of coiled aneurysms were fully occluded initially (P < .001). Retreatments were significantly more common after coiling (12% vs 0.6%; P < .001). CONCLUSION: Both treatment modalities yielded excellent overall outcomes; however, aneurysm complexity strongly influenced treatment selection and outcomes. MT ensured durable aneurysm exclusion and lower retreatment rates, offering particular benefit for complex aneurysms, including blister-like or dissecting subtypes. An individualized, anatomy-based strategy remains essential: MT should be prioritized when managing complex lesions, while EVT remains valuable for appropriately selected simple aneurysms.