Combined assessment of ASPECTS and collateral status predict outcomes after endovascular therapy in patients with large ischemic stroke

Abstract

Background Both the Alberta Stroke Program Early Computed Tomography Score (ASPECTS) and collateral status are well-established predictors of clinical outcomes in patients with large ischemic stroke undergoing endovascular therapy (EVT); however, they have traditionally been assessed independently. This study aimed to evaluate the prognostic value of a combined imaging score, the AS-TCIS score, which integrates ASPECTS and collateral status into a unified framework. Methods This study is a subanalysis of a prospective multicenter cohort including patients with ASPECTS ≤5 enrolled between November 2021 and February 2023. The AS-TCIS score was constructed by integrating the 5-point ASPECTS with collateral status, including the 3-point Tan score and the 8-point comprehensive venous outflow (CVO) score, yielding a 16-point composite scale. The primary outcomes were 90-day functional outcome (modified Rankin Scale [mRS] 0–3) and mortality. Results Of 750 patients, 287 were eligible (median age 67 years; 58.5% male; median AS-TCIS score 8). In multivariable models, each 1-point increase in AS-TCIS was associated with higher odds of mRS 0–3 (OR 1.38; 95% CI 1.24–1.56) and mRS 0–2 (OR 1.30; 95% CI 1.17–1.47), and lower odds of mortality (OR 0.74; 95% CI 0.66–0.82), with no significant association with symptomatic intracranial hemorrhage (OR 0.92; 95% CI 0.82–1.03). AS-TCIS also demonstrated a linear association with functional outcome and mortality. Compared with ASPECTS, Tan score, and their combination, AS-TCIS showed consistently higher AUCs and improved model fit across all outcomes. Conclusion The AS-TCIS score, a composite of ASPECTS and collateral status, was independently associated with 90-day outcomes in patients with large ischemic stroke undergoing EVT. It may provide incremental value for risk stratification and outcome prediction in acute stroke imaging assessment.