Complications of Middle Meningeal Artery Embolization: A Systematic Review and Meta-Analysis

BACKGROUND: Middle meningeal artery embolization (MMAE) is an established treatment option for chronic subdural hematoma. The aim of this systematic review and meta-analysis was to establish estimates of the pooled incidence for complications following MMAE. METHODS: PubMed, Embase, and Cochrane were searched for studies reporting complications following MMAE through January 2023. A random effects model was used to calculate the pooled incidence of complications stratified based on whether studies excluded patients with comorbidities. Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist was followed. RESULTS: A final 34 studies containing 921 patients undergoing MMAE were included that reported 35 complications. Neurological complications were reported in 7 studies with an overall pooled incidence of 3.8% (95% confidence interval [CI]: 2.6%-5.5%). Across these studies, there was a pooled incidence of 4.9% (95% CI: 2.9%-8.0%), 3.0% (95% CI: 1.7%-5.3%), and 2.1% (95% CI: 0.4%-9.7%) in studies that did not exclude, did not mention, or excluded patients with comorbidities, respectively. Similarly, 7 studies reported cardiovascular complications with an overall pooled incidence of 3.6% (95% CI: 2.4%-5.4%), 4 studies reported infectious complications with an overall pooled incidence of 2.9% (95% CI: 1.9%-4.5%), and 3 studies reported for miscellaneous complications with an overall pooled incidence of 3.1% (95% CI: 2.0%-4.8%). Further subgroup analysis revealed the pooled incidence of cardiovascular complications was 3.2% (95% CI: 1.7%-6.1%) in studies that did not exclude patients with comorbidities, 4.1% (95% CI: 2.3%-7.1%) in studies that did not specify the exclusion of such patients, and 1.8% (95% CI: 0.2%-11.5%) in studies that excluded these patients. Similarly, the incidence of infectious complications was 3.3% (95% CI: 1.7%-6.2%), 2.7% (95% CI: 1.5%-5.0%), and 1.8% (95% CI: 0.2%-11.5%) across these groups, respectively. Miscellaneous complications were reported at 4.0% (95% CI: 2.2%-7.2%), 2.3% (95% CI: 1.1%-4.6%), and 3.1% (95% CI: 0.9%-10.1%), respectively. CONCLUSIONS: The published literature suggests that MMAE is a generally well-tolerated procedure with a low risk of significant complications.