Middle Meningeal Artery Embolization for Chronic Subdural Hematoma: Real-World Outcomes using Center for Medicare and Medicaid Services Data

BACKGROUND AND PURPOSE: Middle meningeal artery (MMA) embolization is an evidence-supported endovascular treatment for chronic subdural hematoma (cSDH). This retrospective study evaluated post-discharge clinical outcomes, healthcare utilization, and payments among patients receiving MMA embolization as an adjunct to surgical evacuation compared with surgery evacuation alone. METHODS: Medicare fee-for-service claims from the Centers for Medicare and Medicaid Services were used to identify patients treated in the years 2018 through 2023 for chronic or subacute, non-traumatic subdural hematoma, via surgical evacuation with or without concurrent MMA embolization. Patients were propensity-matched 1:2 using age, sex, region, hospital characteristics, comorbidities, and admission year. The primary outcome was cumulative incidence of readmissions and reinterventions within 180 days post-discharge using Kaplan-Meier survival analysis. Other outcomes included cumulative incidence of post-discharge mortality, infection, and seizure, as well as post-discharge resource utilization and payments. RESULTS: Among 8,208 eligible patients, propensity matching produced balanced patient cohorts of 1,133 surgery-only patients and 577 patients in the surgery plus MMA embolization group. Surgery plus MMA embolization was associated with significantly lower cSDH-related readmissions compared with surgery-only (10.0% vs 15.8% respectively at 180-day; Hazard Ratio 0.60, 95% CI 0.45-0.82; P<0.001). Cumulative incidence of reintervention was also significantly lower in the surgery plus MMA embolization group (7.2% vs 13.8%; at 180-day; Hazard Ratio 0.51, 95% CI 0.36-0.72; P<0.001) Total healthcare expenditures for all-cause and cSDH-related encounters were significantly lower for surgery plus MMA embolization vs surgery-only. All-cause total payments were $30,504 (95% CI $28,378-$32,790) for surgery-only versus $26,689 (95% CI $24,092-$29,567) for surgery plus MMA embolization (P = 0.04) and, when limited to cSDH-associated encounters, total payments were $9,099 (95%CI $8,139-$10,172) for surgery-only versus $5,409 (95% CI $4,602-$6,358) for surgery plus MMA embolization (P < 0.001). The differences in payment amounts were driven by lower payments for care in the acute-care hospital setting. CONCLUSION: In this large Medicare cohort, use of MMA embolization as an adjunct treatment for cSDH was associated with reduced incidence of readmissions and reinterventions, and lower 6-month healthcare expenditures compared with surgical evacuation alone.