Abstract WP107: Differences In Automated Perfusion Softwares: Do They Matter Clinically?

Abstract

Introduction: Treatment of acute ischemic stroke in the late window changed with the positive results of DAWN and DEFUSE III. Both trials required the use of automated perfusion software for inclusion. Because differences in the predicted core or penumbra between software can lead to differences in eligibility for endovascular thrombectomy (EVT), we sought to compare whether these potential differences would have changed eligibility for EVT by DAWN or DEFUSE III criteria. Methods: Patients presenting or transferred to the University of Cincinnati Medical Center between April 23 rd 2019 and July 22 nd 2019 with acute ischemic stroke secondary to large vessel occlusions within the anterior circulation in the extended time window (>6-24 hours) who underwent CT perfusion (CTP) imaging were prospectively tracked. CTP findings, clinical course, age and initial NIHSS were retrospectively reviewed. The primary outcome was EVT eligibility using DAWN or DEFUSE criteria. Secondary outcomes were penumbra (Tmax>6s) and core (CBF<30%) volumes. McNemar test and kappa coefficients were used to assess the agreement in the primary outcome. Intra-class correlation coefficients were used to evaluate the agreement between the software for secondary outcomes. Results: Of 46 included patients, the Viz CTP and RAPID software provided discordant EVT eligibility in 5 cases (4 by DEFUSE criteria and 1 by DAWN). By DAWN criteria, agreement was almost perfect between the software packages (kappa 0.96, 95% CI 0.87-1.00, p<0.0001). By DEFUSE III criteria, the two software demonstrated excellent agreement (kappa 0.82, 95% CI 0.65-0.99, p<0.0001). Discussion: We observed no difference in eligibility for EVT using either software when both DEFUSE and DAWN criteria were considered. If using only one trial’s criteria, 10.6% of patients would have had differing eligibility for EVT depending on the package used, although this difference did not demonstrate statistical significance.