Automated Assessment of the DWI-FLAIR Mismatch in Patients with Acute Ischemic Stroke: Added Value to Routine Clinical Practice

Background and purpose: The DWI-FLAIR mismatch is used to determine thrombolytic eligibility in patients with acute ischemic stroke when the time since stroke onset is unknown. We aimed to use e-Stroke software for automated classification of the DWI-FLAIR mismatch in a cohort of patients with acute ischemic stroke and in a comparative analysis with 2 expert neuroradiologists.

Materials and methods: In this retrospective study, patients with acute ischemic stroke who had MR imaging and known time since stroke onset were included. The DWI-FLAIR mismatch was evaluated by 2 neuroradiologists blinded to the time since stroke onset and automatically by the e-Stroke software. After 4 weeks, the neuroradiologists re-evaluated the MR images equipped with automated e-Stroke results as a computer-assisted tool.

Results: A total of 157 patients met the inclusion criteria. The diagnostic accuracy (AUC/sensitivity/specificity) of e-Stroke software for determination of the DWI-FLAIR mismatch was 0.72/90.0/53.9. Both neuroradiologists significantly improved their accuracy following the use of e-Stroke predictions as a computer-assisted tool, and the interrater agreement improved from 0.49 to 0.57.

Conclusions: This automated quantitative approach for DWI-FLAIR mismatch provides results comparable with those of human experts and can improve the diagnostic accuracies of expert neuroradiologists in the determination of DWI-FLAIR status.