We aimed to compare the perfusion parametric maps and the determination of predicted ischemic core between three automated CT perfusion software packages: RAPID (IschemaView), Viz CTP (Viz.ai) and e-Mismatch (Brainomix).
Retrospectively review of a prospective database spanning September 2018-November 2019 with the following inclusion criteria: 1) acute large vessel occlusion strokes (LVOS) involving the intracranial internal carotid artery or proximal middle cerebral artery (M1 segment), 2) available CTP images, 3) final complete/near-complete endovascular reperfusion (eTICI2c-3) and 4) follow-up imaging with final infarct volume (FIV) assessment.
A total of 242 cases were included. There was a strong correlation for rCBF<30% between RAPID and Viz CTP (rs=0.844, p<.001) as well of RAPID and e-Mismatch (rs=0.833, p<.001). Similarly, strong correlation for Tmax>6s were observed between RAPID and Viz CTP (rs=0.892, p<0.001) as well for RAPID and e-Mismatch (rs=0.752, p<.001). The accuracy for FIV prediction was found to be moderate in all three packages (RAPID: rs=0.637, p<.001; Viz CTP: rs=0.601, p<.001; e-Mismatch: rs=0.605, p<.001)(Figure). Ghost core (defined as FIV overestimation >10ml within 6 hours from stroke onset) was identified in 10 (15.9%) RAPID, 15 (23.8%) Viz CTP and 3 (4.7%) e-Mismatch cases.
The key CTP parameters for the RAPID, Viz CTP and e-Mismatch packages strongly correlate. CTP predictability of final infarct volume remains moderate and requires further evaluation.