Middle meningeal artery embolization in the treatment of chronic subdural hematoma: a systematic review and meta-analysis

Background and Objectives: There is increasing evidence that middle meningeal artery embolization (MMAE) can be used to treat chronic subdural hematoma. The purpose of this study was to demonstrate the efficacy and safety of MMAE treatment through a systematic review and meta-analysis of observational studies and randomized controlled trials (RCTs). Methods: We searched the PubMed, Embase, Cochrane Library and Web of Science databases to obtain articles related to MMAE from inception to December 3, 2024. The effectiveness outcomes are recurrence, progression or reoperation of subdural hematoma after treatment; 90-day mRS 0-2; 90-day mRS 0-3. The safety outcomes are severe deterioration of neurologic function and death within 180 days. The quality of the RCTs is evaluated with the Cochrane risk assessment tool while the cohort studies are evaluated by the Newcastle-Ottawa Scale (NOS). The random effect model is used to calculate the effect as risk ratio (RR). The heterogeneity of the results of each study was analyzed by χ2 test. Results: A total of 892 articles are retrieved. Among those, 4 RCTs and 5 cohort studies met the inclusion criteria. The RCT analysis showed that MMAE plus traditional treatment reduced the risk of recurrence or progression of hematoma compared with traditional treatment alone (5.3% vs 9.1%; RR 0.58, 95%CI 0.39-0.86, P =0.03). The heterogeneity is very low (I2=22%). And in terms of 90-day mRs 0-2 or 0-3 scores, there was no significant difference between the two groups (P=0.73/ P=0.71). In terms of safety outcomes, 180-day mortality is 3.5% in the MMAE plus traditional treatment group and 5.0% in the traditional treatment group(P=0.49＞0.05). In terms of neurological deterioration, MMAE plus traditional treatment is 4.6% and traditional treatment is 3.9%, with no statistical significance (P=0.44＞0.05). Across the 5 cohort studies, similar result is obtained for the incidence of recurrence, progression or reoperation of subdural hematoma (12.9% vs 40.6%; RR 0.26, 95%CI 0.07-0.95, P=0.04), but the heterogeneity was very high (I2 = 89%). Conclusion: This systematic review and meta-analysis showed that in chronic subdural hematoma patients, MMAE was associated with reduced the rate of recurrence, progression or reoperation of subdural hematoma compared to traditional treatment with surgery without increasing the incidence of death or adverse events.