Endovascular drainage of non-acute subdural hematomas and middle meningeal artery embolization: first-in-human study.

Introduction: Large randomized clinical trials have shown that middle meningeal artery embolization (MMAe) is associated with a reduction of recurrences after surgical drainage of non-acute subdural hematoma (SDH). This emerging paradigm of performing two procedures for one condition directly increases patient discomfort and risks, prolongs ICU and hospital stay, and increases the overall healthcare costs. An endovascular technology was developed for MMAe and trans-vascular drainage of a SDH in a single procedure.

Methods: A prospective, single-arm, first-in-human study (EMBODRAIN Study) was conducted to evaluate the safety and feasibility of endovascular drainage of non-acute SDH and MMAe using a purpose-built technology (Endovascular Horizons, Inc) to perforate through the arterial wall and dura to create a transvascular passageway to the subdural space.

Results: Five (5) consecutive patients (all males, average age 75 years) underwent MMAe and endovascular drainage of SDH (including sub-acute, chronic, acute-on-chronic, separated and trabeculated type). Acute technical success defined as a creation of a leak-proof transvascular passageway and access the subdural space with a microcatheter, drainage of the SDH and occlusion of the MMA was achieved in all cases (5/5). No Serious Adverse Events were reported. The SDH volume at baseline was an average of 222 mL and decreased immediately post-procedurally to an average of 40 mL (82% reduction). The SDH thickness at baseline was an average of 24 mm, and decreased post-procedurally to an average of 12 mm. The midline shift at baseline was an average of 8 mm and decreased post-procedurally to an average of 2.8 mm. Head CT at 72-hours did not demonstrate interval hemorrhage in all cases. The average Modified Rankin Scale Score and Markwalder grade decreased from 2.8 and 2, respectively at presentation to 1.8 and 0.8, respectively at 72hrs post-intervention. There were no SDH recurrence or progression requiring surgery, and no deterioration in neurological function.

Conclusion : MMAe and endovascular drainage of a broad range of symptomatic non-acute SDH in a single, fully endovascular procedure is feasible and can attribute to rapid radiographic and clinical improvement.