1041. Cavity volume after minimally invasive endoscopic evacuation is dependent on hematoma size but not time to evacuation

Authors: Rui Song; Maxwell Horowitz, BA; Olivia Allen; Alexander Chartrain, MD; Jacopo Scaggiante, MD; J Mocco, MD; Christopher Kellner, MD (Brooklyn, NY)

Introduction: Minimally invasive endoscopic intracerebral hemorrhage (ICH) evacuation is under investigation in a multicenter randomized clinical trial to evaluate its feasibility, safety, and impact on functional outcomes. Unlike stereotactic thrombolysis, active evacuation often leaves a cavity in place of the hematoma. Here we investigate the significance of the cavity size in patients undergoing this procedure. Methods: 47 consecutive patients presenting with supratentorial ICH underwent MIS endoscopic hematoma evacuation at the Mount Sinai Health System. Cavity volume were analyzed by two separate raters using semi-automated threshold-guided software. Demographic and clinical data were queried from an institutional database. Results: Average age in our cohort was 63.5; eight patients had a premorbid mRS >0. Bleeds in the deep brain structures comprised 70% of the total cohort and IVH occurred concurrently in 51% of hemorrhages. Admission GCS, ICH score, and NIHSS averaged 9.5, 2.1, and 18.2. Average hematoma volume was 44 cc, with percent evacuation reaching 90% on average. Average cavity volume after evacuation was 11.3 cc; cavity size was significantly correlated with pre and post-op hematoma volume (p = 0.03, 0.04 respectively) but not time to evacuation or operative time. Cavity volume was not significantly correlated with hospital length of stay or patient outcomes. Conclusion: While preliminary analyses of a small cohort showed no correlation between cavity volume and outcome, a larger cohort will be needed to fully assess the relationship and the relationship of cavity volume to post-stroke cerebral atrophy. Interestingly, time to evacuation and operative time did not significantly affect cavity size, suggesting that the brain parenchyma retains elasticity even after delayed evacuation.