Large ischemic core defined by visually assessed ASPECTS predicts functional outcomes comparably accurate to automated CT perfusion in the 6-24 h window.

Introduction: Automated CT perfusion (aCTP) is commonly used to select patients with anterior circulation large vessel occlusion (aLVO) for endovascular treatment (EVT). The equivalence of visually assessed Non-contrast CT Alberta Stroke Program Early CT Scores (ASPECTS) and aCTP based selection in predicting favorable functional outcomes remains uncertain.

Patients and methods: Retrospective multicenter study of adult aLVO patients from the Swiss Stroke Registry (2014-2021) treated with EVT or best medical treatment 6-24 h after stroke onset. We assessed ASPECTS on non-contrast CT visually and ischemic core volumes on aCTP, defining ASPECTS 0-5 and aCTP CBF < 30% volumes ⩾50 mL as large ischemic cores. We used logistic regression to explore the association between CT modalities and favorable functional outcomes (modified Rankin Scale [mRS] score shift toward lower categories) at 3 months. Receiver operating characteristic (ROC) curve analysis compared the predictive accuracy of visually assessed ASPECTS and aCTP ischemic core for favorable outcomes (mRS 0-2) at 3 months.

Results: Of 210 patients, 11.4% had ASPECTS 0-5, and 12.9% aCTP core volumes ⩾50 mL. Within the same model, ASPECTS but not aCTP core volumes were associated with favorable outcomes (ASPECTS: acOR 1.85, 95%CI 1.27-2.70, p = 0.001). The ROC curve analyses showed comparable diagnostic accuracy in predicting favorable functional outcomes (mRS 0-2) at 3 months (ROC areas: ASPECTS 0.80 [95%CI 0.74-0.86] vs aCTP core 0.79 [95%CI 0.72-0.85]).

Discussion and conclusion: In patients with aLVO, visually assessed ASPECTS showed at least comparable accuracy to automatically generated CTP core volumes in predicting functional outcomes at 3 months.