Surgical Performance in Minimally Invasive Surgery Plus Recombinant Tissue Plasminogen Activator for Intracerebral Hemorrhage Evacuation Phase III Clinical Trial

Abstract

Background: Minimally invasive thrombolytic evacuation of intracerebral hematoma is being investigated in the ongoing phase III clinical trial of Minimally Invasive Surgery plus recombinant Tissue plasminogen activator for Intracerebral hemorrhage Evacuation (MISTIE III).

Objective: To assess the accuracy of catheter placement and efficacy of hematoma evacuation in relation to surgical approach and surgeon experience.

Methods: We performed a trial midpoint interim assessment of 123 cases that underwent the surgical procedure. Accuracy of catheter placement was prospectively assessed by the trial Surgical Center based on prearticulated criteria. Hematoma evacuation efficacy was evaluated based on absolute volume reduction, percentage hematoma evacuation, and reaching the target end-of-treatment volume of <15 mL. One of 3 surgical trajectories was used: anterior (A), posterior (B), and lobar (C). Surgeons were classified based on experience with the MISTIE procedure as prequalified, qualified with probation, and fully qualified.

Results: The average hematoma volume was 49.7 mL (range 20.0-124), and the mean evacuation rate was 71% (range 18.4%-99.8%). First placed catheters were 58% in good position, 28% suboptimal (but suitable to dose), and 14% poor (requiring repositioning). Posterior trajectory (B) was associated with significantly higher rates of poor placement (35%, P = .01). There was no significant difference in catheter placement accuracy among surgeons of varying experience. Hematoma evacuation efficacy was not significantly different among the 3 surgical approaches or different surgeons' experience.

Conclusion: Ongoing surgical education and quality monitoring in MISTIE III have resulted in consistent rates of hematoma evacuation despite technical challenges with the surgical approaches and among surgeons of varying experience.

Keywords: Alteplase; Intracerebral hemorrhage; MISTIE; Minimally invasive; Tissue plasminogen activator.

FIGURE 1.

Surgical approaches in MISTIE III. A, Trajectory A is used when ICH epicenter is at the caudate, putamen, or anterior capsule, with an entry point at the forehead. B, Trajectory B is used when ICH epicenter is posterior capsular or thalamic, with an entry point in the posterior parietal-occipital area. C, Trajectory C is used for lobar ICH and has an entry point at the superficial area of the ICH closest to the cortical surface, with a trajectory along the widest, or “equatorial,” axis of the clot.

FIGURE 2.

Efficacy of hematoma evacuation over time. A graph illustrating the distribution of clot evacuation rates in subjects randomized to the surgical arm in the first half of the trial. The plot also shows the overall consistency of ICH evacuation efficacy over time as demonstrated by average clot evacuation rate and percentage of subjects reaching target end-of-treatment volume <15 mL. Two cases experienced hematoma size expansion by the end of treatment resulting in a negative clot evacuation rate.