Cortical Vein Opacification Score Predicts Stroke Outcomes after Thrombectomy: A Frequentist and Bayesian Meta-Analysis

Introduction: Good cortical venous outflow has been considered in association with favorable functional outcomes (FFOs) for large vessel occlusion-related stroke patients treated after an intra-arterial endovascular thrombectomy (IA-EVT). Methods: A diagnostic meta-analysis was performed using the index test of cortical vein opacification score (COVES) on computed tomographic angiography for prediction of 3-month FFOs (reference standard). Literature search for relevant articles was conducted in PubMed, Embase, and Scopus databases from January 1, 2014, to July 8, 2024. The Bayesian analyses were conducted to estimate posttest probabilities (PTPs). Results: Ten studies and 2,238 patients were enrolled. While excluding studies conducted in duplicated cohorts, four studies defined a favorable COVES as ≥1 and another four studies defined a favorable COVES as ≥3. In studies using a favorable COVES of ≥1, the COVES showed a sensitivity of 0.86 (95% confidence interval [CI], 0.48–0.97), a specificity of 0.47 (95% CI, 0.31–0.64) for predicting 3-month FFOs. With a pretest probability of an FFO of 0.19, the COVES increased the PTP to 0.28. In studies using a favorable COVES of ≥3, the COVES showed a sensitivity of 0.76 (95% CI, 0.58–0.88), a specificity of 0.71 (95% CI, 0.65–0.76) for predicting 3-month FFOs. On a pretest probability of an FFO by 0.19, the COVES increased the PTP to 0.37. Conclusion: This meta-analysis showed the high sensitivity and moderate specificity of a COVES of ≥3 to select patients who can benefit from an IA-EVT.