Abstract 328: Middle Meningeal Artery Embolization In Chronic Subdural Hematoma: Technical Nuances And Preliminary Outcomes
Authors: Armindo R. Duarte , Sequeira S. , Oliveira J. , Morgado D. , Andrade J. , Reizinho C. , Vilela P. 
Published: January 2025

Introduction
Chronic subdural hematoma (cSDH) is one of the most prevalent forms of intracranial hemorrhage, and its complex pathogenesis is frequently associated with difficult reabsorption, recurrence after surgical draining, and in some cases, spontaneous hematoma expansion. It is globally one of the most commonly encountered neurosurgical conditions, with up to 30% requiring surgical drainage. Recently presented randomized trials (EMBOLISE, MAGIC‐MT, and STEM) show that middle meningeal artery embolization (MMAE) is a safe and effective technique for the prevention of cSDH recurrence or progression, legitimizing its use in clinical practice. The authors present the first cohort of patients with cSDH submitted to MMAE prospectively studied in their country.

Materials/Methods
Patients were prospectively enrolled in this study through consensus decisions at inter‐specialty neurovascular treatment decision meetings. The main indications/inclusion criterie were recurrent non‐acute subdural hematomas following surgical therapy; persistent clinically relevant non‐acute subdural hematomas under conservative management; and subdural hematomas in patients undergoing anticoagulant and/or antiplatelet therapy (aiming for early resumption of the antithrombotic status).The study protocol requires the assessement clinical and imaging outcomes at fixed intervals post‐MMAE (1 week, 1 month, 3 months, 6 months, 1 year). Endovascular embolization was performed under local anesthesia, with a permanent occlusive agent (preferably cyanoacrylate, n‐BCA) distally to any “dangerous” (ECA‐ICA) anastomosis. For additional safety reasons, the guiding catheter was placed in the main trunk of the ECA and an intermediate catheter on the IMA. Closure of the punture site was obtained with an endovascular hemostasis device.

Results
Fourteen consecutive patients (mean age: 77.2 years, female:male ratio of 5:2), corresponding to 23 MMAEs, were included, with a median follow‐up period of 5 months (range: 3‐12 months). There was evidence of bilateral disease in 64% of patients. Half of the patients had been previously submitted to surgical evacuation; in 14%, the MMAE was done adjunctively to surgical drainage, and the other 36% were embolized only. Three patients complained of self‐limited headache until up to 4 weeks after the procedure. Discharge was on average 4 days after the procedure (median of 2 days, with only two patients having hospitalization longer than one week). One patient was re‐admitted two days after the procedure with sudden‐onset hemiparesis and dysarthria (final diagnosis of TIA, no DWI‐positive lesions on MRI). During the follow‐up period there was an average reduction of mRS of 1.1 (average mRS pre‐procedure of 2.3, post‐procedure of 1.2), with no patient showing worsening of the mRS on subsequent evaluations and improved clinical status reported in 92% of patients. There were no neurosurgical reinterventions in the cohort.

Conclusion
MMAE with n‐BCA is a safe and effective technique for managing chronic subdural hematoma, demonstrating significant clinical improvement and reducing the need for neurosurgical reintervention. The results of this small “real‐world” cohort support the inclusion of MMAE in the treatment protocols for cSDH.