Cost-Effectiveness of Adjunctive Middle Meningeal Artery Embolization for Chronic Subdural Hematoma: Secondary Analysis of EMBOLISE

BACKGROUND AND PURPOSE: Chronic subdural hematoma (cSDH) has high recurrence rates after evacuation surgery (ES). Adjunctive middle meningeal artery embolization (MMAE) to ES reduces recurrence but increases hospital costs. This study evaluated the cost-effectiveness of adjunctive MMAE (ES/MMAE) versus ES alone as a secondary post-hoc analysis of the EMBOLISE randomized trial of ES/MMAE vs ES alone. MATERIALS AND METHODS: Cost-effectiveness analysis using 2024 U. S. dollars was conducted averaging hospital costing data from two EMBOLISE trial sites for 42 cSDH patients (21 ES/MMAE, 21 ES alone) from a U. S. hospital (health facility) perspective, with clinical data (e. g. , cSDH recurrence rates) derived from the EMBOLISE trial. Quality-adjusted life years (QALYs) were derived from EQ-5D-5L data with a 180-day horizon. Incremental cost-effectiveness ratio (ICER) was calculated. One- and two-way sensitivity analyses and probabilistic sensitivity analysis (PSA) with 5, 000 Monte Carlo iterations (gamma distributions for costs and beta for utilities/probabilities) were performed. RESULTS: Mean expected costs were 23, 809 for ES/MMAE (4. 1% recurrence rate), 17, 197 for ES alone (11. 3% recurrence rate), and 10, 376 for rescue surgery for either treatment. ES/MMAE provided a 0. 02 QALY gain over ES alone, at an incremental cost of 6, 612. The resultant ICER was approximately 382, 267. 50/QALY, exceeding the commonly cited 100, 000/QALY cost-effectiveness criterion. One-way sensitivity analyses indicated QALY gain was the most impactful economic driver. PSA indicated a 31. 8% probability of ES/MMAE being cost-effective at 100, 000/QALY (68. 2% for ES alone). CONCLUSIONS: At 2024 pricing, and from a U. S. hospital perspective, ES/MMAE for cSDH may not be cost-effective within a 180-day horizon, but PSA suggests a greater favorability towards ES/MMAE at higher willingness-to-pay thresholds. The positive net QALY benefit with adjunctive MMAE for cSDH suggests a small but meaningful quality-of-life improvement, preventing complete ES dominance. Cost-reduction strategies, longer time frames, and validated cSDH-specific patient-reported outcome measures could enhance ES/MMAE cost-effectiveness. These findings could guide future optimization efforts for ES/MMAE for cSDH management.