369 Surgical Performance in Early Minimally Invasive Removal of Intracerebral Hemorrhages: An ENRICH Post-Hoc Analysis

INTRODUCTION: Minimally invasive evacuation of intracerebral hemorrhage (ICH) was recently investigated in the Early Minimally Invasive Removal of Intracerebral Hemorrhage (ENRICH) trial, which showed a clinical benefit over medical treatment. METHODS: We performed a post-hoc analysis of the surgical arm of the ENRICH trial. Surgeons' experience was categorized as novice, intermediate, and expert per trial design and also computed in months of practice since licensing. Institutions were classified as comprehensive stroke centers(CSC) or not and teaching or non-teaching facilities. Bayesian mixed-effect regression models were used to predict absolute end-of-treatment volume (EOTV), EOTV-to-preoperative volume ratio, utility-weighted Modified Rankin Scale (uwMRS), and mortality. RESULTS: Average pre- and post-operative ICH volumes(ml) were 54.39[39.44-72.42] and 7.18[1.93-17.53]. Optimal target EOTV was obtained in all surgical categories (novice: 8.76[1.83-22.54], intermediate: 5.37[1.93-13.51], expert: 6.95[2.20-21.13]). Higher preoperative volume (B:1.01 [1.002-1.02]) and admission to non-teaching hospitals (B:0.31[0.14-0.94]) but not surgical experience were independent predictors of lower EOTV. Moreover, hemorrhage location (B:0.22[0.1-0.33]), preoperative volume (B:-0.003[-0.01-(-0.001)], preoperative GCS (B:0.03[0.01-0.05]) and age(B:-0.01[-0.01-(-0.003)] but not surgical experience were predictors of higher uw-mRS scores. Age (OR:1.07[1.03-1.13]) and preoperative GCS (OR:0.78[0.64-0.94]) were the major predictors of mortality at 180 days. CONCLUSIONS: These findings showed consistent rates of hematoma evacuation and functional outcome through a reproducible minimally invasive surgical technique. Technical proficiency using this standardized approach as determined by EOTV remained high regardless of surgical experience or institutional setting.