Investigating Intracerebral Hemorrhage Evacuation Procedure Volumes Before and After the Minimally Invasive Surgery Plus Alteplase for Intracerebral Hemorrhage Evacuation III (MISTIE III) Trial

Introduction Intracerebral hemorrhage (ICH) constitutes 10-15% of all strokes in the United States and has a 30-40% mortality rate. The Minimally Invasive Surgery Plus Alteplase for Intracerebral Hemorrhage Evacuation III (MISTIE III) trial showed no significant functional benefit of minimally invasive catheter drainage (MICD) and postoperative thrombolysis compared to medical management. Our objective is to evaluate how the results of the MISTIE III trial corresponded to changes in ICH evacuation procedure volumes. Materials and methods We used an aggregated dataset containing Medicare Part B procedure data from 2013 to 2023. We calculated the normalized volume of MICD procedures, supratentorial craniotomies, and infratentorial craniotomies for ICH evacuation. We normalized the volumes by calculating the percentage of all neurosurgical procedures that included ICH evacuation for each year. We used an interrupted time series (ITS) to find statistically significant changes in volumes before (βpre) and after (βpost) 2019, when the MISTIE III results were published. Results Normalized MICD volumes increased slightly before 2019 (βpre = 0.0001, p = 0.022). After 2019, MICD volumes increased more dramatically over the long term than would have been expected based on the pre-2019 trend (βpost = 0.0028, p < 0.001). However, supratentorial and infratentorial craniotomy volumes, as well as overall ICH evacuation volumes across all procedure types, showed no significant long-term change (p = 0.091, p = 0.18, p = 0.68, respectively). Conclusions The results of MISTIE III did not show a benefit of MICD over medical management for ICH with respect to the primary outcome of functional independence. We found that, despite these results, MICD evacuation procedure volumes increased significantly after the publication of the MISTIE III results. However, this association is only correlative, and other factors besides MISTIE III could have affected procedure volumes.