Venous collaterals in acute ischemic stroke patients after endovascular treatments: a novel scoring system using 4D computed tomography angiography

BACKGROUND: To establish a novel cortical venous collateral score based on four-dimensional computed tomography angiography (4D CTA) and to assess the relationship between the score and clinical outcomes in patients with acute ischemic stroke (AIS) after endovascular treatments (EVTs). METHODS: This was a retrospective case-control study designed to evaluate all consecutive patients with large vessel occlusion in unilateral anterior circulation who underwent EVTs at a single institution. Two independent neuroradiologists evaluated venous collaterals using different venous collateral scores: a cortical venous collateral score based on 4D CTA (4D-VCS), the prognostic evaluation based on cortical vein score difference in stroke (PRECISE) score, and the cortical vein opacification score (COVES). Spearman correlation analysis was used to analyze the correlation of different venous collateral scoring systems with final infarct volume (FIV), modified Rankin Scale (mRS) score, and artery collateral score. Multivariate logistic regression analysis was used to identify the prognostic value of each model. The areas under the curve (AUC) of the receiver operating characteristic (ROC) curve of the 6 models were compared by the DeLong test. RESULTS: A total of 107 patients were enrolled in the study. The AUC of 4D-VCS was 0.92 [95% confidence interval (CI): 0.85 to 0.96; P<0.0001]. The 4D-VCS was highly correlated with FIV (r=−0.615; 95% CI: −0.737 to −0.473; P<0.001), mRS score (r=−0.706; 95% CI: −0.789 to −0.602; P<0.001), and arterial collateral score (r=0.769; 95% CI: 0.678 to 0.838; P<0.001). There were statistically significant differences between model 1 (AUC, 0.89; 95% CI: 0.81 to 0.94) and model 2 (AUC, 0.94; 95% CI: 0.88 to 0.98) (P=0.025), model 1 (AUC, 0.89; 95% CI: 0.81 to 0.94) and model 3 (AUC, 0.93; 95% CI: 0.87 to 0.97) (P=0.045), model 1 (AUC, 0.89; 95% CI: 0.81 to 0.94) and model 6 (AUC, 0.95; 95% CI: 0.89 to 0.98) (P=0.011), and model 2 (AUC, 0.94; 95% CI: 0.88 to 0.98) and model 5 (AUC, 0.89; 95% CI: 0.82 to 0.94) (P=0.032). CONCLUSIONS: The findings of this study suggested that 4D-VCS, a novel measurement of venous enhancement based on 4D CTA, may be accurately used to identify AIS patients with high risk of poor clinical outcome after EVTs.