Assessing Brain Lesions and Predicting Functional Outcome in Patients With Anterior Circulation Stroke With Endovascular Therapy: Co-ASPECTS.

BACKGROUND: This study aimed to develop and validate a practical and reliable tool for comprehensive assessment of brain lesions on immediate post-endovascular therapy (EVT) noncontrast computed tomography (CT) and to predict 90-day functional outcomes in patients with acute ischemic stroke. METHODS: We retrospectively reviewed consecutive patients with acute ischemic stroke undergoing EVT from 2 academic hospitals as the development cohort and used an independent national multicenter prospective cohort for external validation. The new score was derived from the Alberta Stroke Program Early CT Score (ASPECTS) on the immediate post-EVT non-contrast CT, integrating both hyperdensity and hypodensity signs, named comprehensive Alberta Stroke Program Early CT Score (Co-ASPECTS). Unfavorable outcome was defined as modified Rankin Scale score of 3 to 6 at 90 days. RESULTS: A total of 1015 patients were included (development cohort: 542; validation cohort: 473). Co-ASPECTS, formulated through equal-weight summation of hyperdensity and hypodensity signs and consistent with the 0 to 10 score ASPECTS framework, was significantly associated with unfavorable outcomes (adjusted odds ratio, 0.45 [95% CI, 0.40-0.51]). It showed discrimination for functional outcome with a C-statistic of 0.889 in the development cohort, outperforming conventional models including baseline ASPECTS and immediate post-EVT ASPECTS that calculated based on hyperdensity or hypodensity signs alone. In the validation cohort, Co-ASPECTS maintained robust performance (C-statistic, 0.847). It also appeared to reflect both infarct burden and secondary injury, showing associations with final infarction and intracranial hemorrhage. CONCLUSIONS: Co-ASPECTS may serve as a promising tool with reliability and practicality for assessing brain lesions and predicting functional outcomes of patients with acute ischemic stroke who underwent EVT in clinical practice.