Abstract WP353: Bleeding Following Removal of Intracerebral Catheters in MISTIE III

Introduction: Minimally invasive surgery plus alteplase has been shown to effectively reduce the volume of intracerebral hemorrhage in patients with supratentorial bleeds. Removal of these catheters is a unique timepoint when bleeding may restart due to mechanical forces and/or the presence of alteplase/plasmin in the brain. We hypothesized that surgically-treated patients in the MISTIE III trial who had increased bleeding post catheter removal would have shorter periods of time between last dose and catheter removal and be less likely to have lobar ICH. Methods: MISTIE III is a prospective, randomized trial testing the efficacy of minimally invasive surgery plus alteplase for hematoma removal compared to medical management. We analyzed 107 surgically-treated patients. Semi-automated threshold based segmentation of the ICH volumes for all time points were performed using OsiriX. Results: Of the 107 surgical patients, 16 experienced an increase in ICH volume >10% between T1, the scan taken 24 hours prior to cath removal, and T2, the scan taken 24 hours post catheter removal. Mean percent difference between T1 and T2 was 37.5% for those that expanded versus those that did not, -17.4% (p<0.001) with an absolute difference in ICH volume of 3.0 cc and -2.2 cc (p<0.001). The mean residual volume at T2 for both groups was similar at 12.84 cc and 12.71 cc, respectively (p=0.96). Time from last dose to catheter removal in days was 1.27 for those that expanded and 1.44 for those that did not (p=0.09). Furthermore, 14/16 (87.5%) patients with expansion had ICH’s located in deep structures compared to 55/91 (60.4%) of patients that did not expand (p<0.01). Conclusion: Overall, incidence of bleeding following ICH catheter removal in MISTIE III was low. When bleeding was seen, it was more often found in patients with deep ICH locations and whose catheters were removed sooner after the last dose of alteplase.