Adjunctive middle meningeal artery embolization for chronic subdural hematoma: a systematic review and meta-analysis of randomized controlled trials

BackgroundTo evaluate the efficacy and safety of adjunctive middle meningeal artery embolization (MMAE) versus standard care alone in symptomatic, non-emergent chronic subdural hematoma (CSDH) based on randomized trials data.MethodsA systematic search (inception - Nov 2024) identified eligible RCTs. Quality was assessed with the Cochrane Risk of Bias tool. Pooled analysis compared recurrence, progression, or surgical rescue at 90 or 180 days between adjunctive MMAE and control. MMAE-related serious adverse events (SAEs) were pooled as logit-transformed proportions with Clopper-Pearson intervals and mRS changes were pooled using binomial variance in R (v4.1.2).Results3 RCTs (EMBOLISE, STEM, MAGIC-MT) with 1432 patients (MMAE :706 [49.30%], Control :726 [50.70%]) met our inclusion criteria. Mean age was 72.50 +/- 10.90 years , and 1104 patients (82.70%) were male . Common symptoms included headache (61.10%) . Antithrombotic use was 23.0% and 50.80% of hematomas were left-sided. Mean hematoma volume was 156.23 mm3 and thickness was 21.3 mm . The risk of recurrence, progression, or surgical rescue was lower with MMAE (RR = 0.50, 95% CI: 0.37-0.69). No difference was seen in all-cause mortality (RR = 1.01, 95% CI: 0.09-10.95) or stroke (RR = 1.07, 95% CI: 0.28-4.13). SAEs related to MMAE were 3% (95% CI:0.00-0.31). Baseline mRS (0-2) was similar between groups (MMAE:0.97, 95% CI:0.08-1.00; Control:0.97, 95% CI:0.06-1.00) and remained comparable at 90 days (MMAE:0.83, 95% CI:0.61-0.94; Control:0.82, 95% CI:0.68-0.91).ConclusionsAdjunctive MMAE reduces the risk of recurrence, hematoma progression, or the need for surgical rescue compared to standard care, without increasing all-cause mortality or stroke, while achieving comparable functional outcomes (mRS 0-2) at 90 days.