Abstract Body: Background: Subacute and chronic subdural hematoma is amongst the most common neurosurgical conditions, with rates that are expected to grow as the population ages. Although surgical management is technically straightforward, high recurrence rates and comorbidities amongst the primarily elderly population make minimally invasive alternatives for treatment attractive. The objective of this trial is to evaluate the safety and effectiveness of Onyx LES embolization of the middle meningeal artery (MMA) for symptomatic subacute and chronic subdural hematoma.
Methods: EMBOLISE is a multicenter, prospective, randomized interventional trial enrolling 200 subjects in the observation cohort across 46 US centers. Subjects with a symptomatic subacute or chronic subdural hematoma that meets criteria for surgical evacuation are randomized 1:1 to receive medical management alone versus adjunctive MMA embolization. The primary objective is to assess the rate of hematoma recurrence / progression requiring surgical drainage within 90 days post-treatment, comparing the experimental and control groups. Secondary objectives evaluate clinical, radiographical, and health economic outcomes between the randomized treatment groups. The trial is funded by Medtronic Neurovascular.
Results: Between December 2020 and September 2024, 200 subjects were enrolled with mean age 72 years (range 21-90) years. Of these, 27% were female. Follow-up is currently on-going. Demographics, intraoperative data, and available safety and effectiveness results (including Core Lab adjudicated outcomes) will be presented through the primary endpoint at 90 days.
Conclusion: Embolization of the MMA shows promise as a minimally invasive adjunct to medical treatment of subacute and chronic subdural hematomas. This randomized trial is the first to report well-powered safety and effectiveness from 200 consecutive non-operative cases.