Abstract 177: A Single‐Center Retrospective Safety Review of Middle Meningeal Artery (MMA) Embolization for Management of Chronic Subdural Hematomas (cSDH)
Authors: King H. , Brar S. , Nasim S. , Patel A. , Torbati T. , Bonabi S. , Levinson K. , Taqi M. A. 
Published: January 2025

Introduction
Chronic subdural hematoma is a disease encountered in elderly populations with cited frequencies of 1.7‐20.6 patients per 100,000 people yielding significant morbidity and mortality (Feghali). It is associated with a 5‐30% recurrence rate despite surgical evacuation (Kan). The pathophysiology involves a complex inflammatory reaction leading to angiogenesis and continued hematoma expansion (Holl). The traditional management of cSDH has historically been neurosurgical drainage either with craniotomy, Burr holes, or craniectomy (Mehta). These treatment techniques however, have been associated with higher rates of recurrence when compared to MMA embolization (Ironside). MMA embolization is a newer technique being offered to patients for management of cSDH that has proven to be highly effective (Catapano). Several recent studies comparing MMA embolization to traditional surgical treatment are beginning to show improved clinical outcomes, hospital days, recurrence rates, and complications (Srivatsan, Ban).

Methods
We collected all data regarding MMA embolization for patients with cSDH between March 2019 and August 2024 admitted to a single comprehensive stroke center in Thousand Oaks, CA. Demographic data, neurologic deficits, and radiologic reports were obtained through the electronic medical record. Procedural details were noted including any periprocedural complications, as well as the need for any surgical intervention. Repeat radiologic findings were reported, in addition to pertinent events that occurred during hospitalization and disposition. Major complications reported were periprocedural stroke, perioperative bleeding requiring transfusion, catheter detachment, and vascular dissection. Minor complications included contrast allergy and groin hematoma.

Results
120 patients were admitted for cSDH and treated with MMA embolization. 34% of patients were female. Comorbidities include hypertension, diabetes mellitus, atrial fibrillation in 20%, 62%, and 14%, respectively. 30% of patients were receiving antithrombotics prior to the procedure (antiplatelets and dual oral anticoagulants). 39% were right‐sided SDH, 34% left‐sided SDH, and 27% bilateral SDH. Average size was 13.8mm and 4.8mm midlife shift. 71% of patients were treated with bilateral MMA embolization and 29% were treated with unilateral MMA embolization. Decision to treat bilateral or unilateral MMA embolization depended on neurointerventionalist preference. 52% of cases required surgical evacuation as well. There were 0 major complications and 0 minor complications. Average length of stay was 12 days and 42% of patients were discharged to home.

Conclusions
Our single center retrospective review of MMA embolization demonstrated that the procedure is safe indicated by our low complication rates. With the increased use of antithrombotic medications in an aging population, the frequency of chronic subdural hematomas is anticipated to expand, and MMA embolization offers a safe treatment option to prevent recurrence. This project contributes to growing fund of research for MMA embolization becoming the standard of care for cSDH.