Efficacy of middle meningeal artery embolization combined with surgery versus standalone surgery for chronic subdural hematoma: a comprehensive systematic review and Meta-Analysis with separate analysis of randomized controlled trials.

Background: Chronic subdural hematoma (CSDH) is a prevalent neurosurgical condition with high recurrence rates after standard surgical evacuation. Middle meningeal artery embolization (MMAE) has emerged as a potential adjunct to reduce recurrence by targeting the vascular supply of neomembranes.

Objective: To evaluate the efficacy and safety of MMAE combined with surgery versus standalone surgical evacuation in patients with CSDH, through a comprehensive systematic review and meta-analysis, including separate analysis of randomized controlled trials (RCTs).

Methods: A systematic search of PubMed, Scopus, Web of Science, Embase, and Google Scholar was performed through March 2025. Dual-arm studies comparing MMAE plus surgery with surgery alone were included. Outcomes of interest were recurrence, complications, all-cause mortality, and functional outcome (modified Rankin Scale ≤ 2; mRS ≤ 2). Pooled risk ratios (RRs) with 95% confidence intervals (CIs) were estimated using a random-effects model. Bias and evidence certainty were assessed via RoB tools and GRADE.

Results: Twenty-five studies (6 RCTs, 19 observational) comprising 119,812 patients were included. MMAE plus surgery significantly reduced recurrence (RR = 0.47, 95% CI: 0.36-0.62, p < 0.001; I² = 3.0%), without increasing complications (RR = 1.02, 95% CI: 0.8-1.3) or mortality (RR = 0.98, 95% CI: 0.72-1.33) compared with surgery alone. Functional outcomes were similar between both approaches (RR = 1.07, 95% CI: 0.93-1.23). Subanalysis of RCTs, was consistent with overall analysis showing a significant reduction in recurrence (RR = 0.44, 95% CI: 0.25-0.78) with MMAE plus surgery, without an increase in complications or mortality compared to surgery alone.

Conclusion: MMAE as an adjunct to surgery significantly lowers recurrence in CSDH. No significant differences in complications, mortality, or functional outcomes were detected compared with surgery alone; however, these outcomes are less common, and available studies may not have been adequately powered to exclude small but clinically meaningful effects.