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Clinical Trial
. 2022 Jan;28(1):139-144.
doi: 10.1111/cns.13756. Epub 2021 Nov 16.

Does variability in automated perfusion software outputs for acute ischemic stroke matter? Reanalysis of EXTEND perfusion imaging

Andrew Bivard  1 , Leonid Churilov  1 , Henry Ma  2 , Christopher Levi  3 , Bruce Campbell  1 , Nawaf Yassi  1 , Atte Meretoja  1   4 , Henry Zhao  1 , Gagan Sharma  1 , Chushuang Chen  5 , Stephen Davis  1 , Geoffrey Donnan  1 , Bernard Yan  1 , Mark Parsons  6 ; EXTEND investigators
Affiliations
Clinical Trial

Does variability in automated perfusion software outputs for acute ischemic stroke matter? Reanalysis of EXTEND perfusion imaging

Andrew Bivard et al. CNS Neurosci Ther. 2022 Jan.

Abstract

Aims: We reprocessed the Extending the time for Thrombolysis in Emergency Neurological Deficits (EXTEND) perfusion imaging with a different automated software with the aim of comparing mismatch eligibility and outcomes.

Methods: EXTEND baseline perfusion imaging data were reprocessed using autoMIStar software to identify patients who were eligible based on the same target mismatch criteria as per the original trial.

Results: From the 225 patients fulfilling RAPID-based mismatch criteria randomized in the EXTEND study, 196 (87%) patients met the revised mismatch criteria. Most common reasons for not meeting revised criteria were core >70 ml (n = 9), and no perfusion lesion/lack of penumbral tissue (n = 20). The revised perfusion lesion volumes were significantly smaller compared to the original RAPID volumes (median 68 ml IQR 34-102 ml vs. 42 ml 16-92 ml, p = 0.036). Of the patients who met the revised mismatch criteria, 40% receiving alteplase had modified Rankin Scale (mRS) 0-1 at 3-month compared to 28% with placebo (Adjusted Odds Ratio (OR) = 2.23, CI 1.08-4.58, p = 0.028). In contrast, in the original mismatch cohort, 35% receiving alteplase had mRS 0-1 at 3-month compared to 30% with placebo (adjusted OR = 1.88, p = 0.056).

Conclusions: These data reinforce the benefit of alteplase in the later time window, and suggest that differences in automated perfusion imaging software outputs may be clinically relevant.

Trial registration: ClinicalTrials.gov NCT00887328 NCT01580839.

Keywords: CT perfusion; ischemic stroke; target mismatch; thrombolysis.

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Conflict of interest statement

Dr. Davis, receiving advisory board fees from AstraZeneca and Boehringer Ingelheim; and Dr. Donnan, receiving advisory board fees from AstraZeneca Australia, Bayer, Boehringer Ingelheim, Merck, Pfizer, and Servier; Dr. Parsons reports receiving advisory board fees from Boehringer Ingelheim, and research partnerships with Canon Medical Systems, Apollo Medical Imaging, and Siemens. No other potential conflict of interest relevant to this article were reported.

Figures

FIGURE 1
FIGURE 1
Modified Rankin Scale Scores at 90 days of the participants meeting the revised target mismatch criteria in the EXTEND study. Patients in the rtPA group have improved functional outcome at 90 days
See this image and copyright information in PMC

References

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