Longitudinal hematoma resolution after burr-hole evacuation with adjunctive scepter mini-assisted middle meningeal artery embolization: A multicenter matched cohort study

OBJECTIVES: To evaluate the radiographic and clinical outcomes of adjunctive middle meningeal artery embolization (MMAE) performed with the Scepter Mini dual-lumen balloon microcatheter following burr-hole evacuation for chronic subdural hematoma (cSDH), and to explore the feasibility of characterizing distal embolic penetration using the proposed MMA Embolization Penetration Score (MMA-EPS). METHODS: This retrospective multicenter matched cohort study included consecutive patients with cSDH treated with burr-hole evacuation followed by adjunctive MMAE using the Scepter Mini and Onyx™ 18. A matched historical cohort treated with burr-hole evacuation alone served as controls. The primary endpoint was longitudinal hematoma thickness regression on serial computed tomography. Secondary endpoints included functional outcome, recurrence, all-cause mortality, and procedural safety. RESULTS: Twenty-two patients with 38 embolized cSDHs were compared with 22 matched controls comprising 38 cSDHs. All embolized hematomas achieved MMA-EPS Grade 3 or 4 and demonstrated complete radiographic resolution by 6 months, whereas residual hematoma persisted in controls (0.0 ± 0.0 vs. 0.7 ± 0.9 mm). Favorable functional outcome (mRS 0-2) at 6 months was achieved in 86.4% versus 45.5% of patients. Exploratory analyses showed numerically lower recurrence (4.5% vs. 13.6%) and all-cause mortality (0% vs. 13.6%) following MMAE; however, the study was not powered to assess differences in these endpoints. Technical success was achieved in all embolizations without major procedure-related complications. CONCLUSION: Adjunctive MMAE using the Scepter Mini dual-lumen balloon microcatheter was associated with accelerated hematoma resolution, improved functional recovery, and an excellent procedural safety profile compared with burr-hole evacuation alone.