Abstract Body: Background: Posterior circulation (PC) large-vessel occlusion (LVO) strokes have significant morbidity and mortality, but patient selection for acute interventions remains understudied. Multiple computed tomography (CT)-based scores exist, including the CT-perfusion-based CAPS score, CT-angiogram(CTA)-based BATMAN and PC-CTA scores, and CTA source image or non-contrast-CT-based PC-ASPECTS score, but their predictive values for long-term outcomes after thrombectomy have not been directly compared.
Methods: We conducted a retrospective multicenter cohort study of patients with basilar artery occlusions treated with endovascular thrombectomy. Four CT-based scores were assessed: PC-ASPECTS, BATMAN, PC-CTA, and CAPS. The primary outcome of interest for the study was favourable functional outcome at 3 months (mRS of 0-3). We generated receiver operating characteristic curves measuring area under the curve (AUC) for poor functional outcomes and compared AUCs with non-parametric methods.
Results: 98 patients were included for analysis, with an average age of 64.9±15.6 years.
The median National Institute of Health Stroke Severity Score (NIHSS) was 13.5 (IQR 7.0 – 23.0). AUC values were highest for the CAPS score (AUC 0.72 (95%CI 0.63 – 82)), and lowest for the pc-CTA score (AUC 0.57 (95%CI 0.45 – 0.68)), p=0.019. There was a trend towards the CAPS score outperforming the BATMAN (AUC 0.66 (95%CI 0.55 – 0.77) and PC-ASPECTS scores (AUC 0.63 (95%CI 0.52 – 0.75)), though this difference was not statistically significant (p=0.29 and p=0.23, respectively). However, the CAPS score was the only score with 100% specificity for predicting inability to achieve good functional outcome after thrombectomy: 0/12 patients with CAPS score of 4-6 went on to have a good functional outcome at 3 months after thrombectomy.
Conclusion: Our analysis demonstrated that the CT-perfusion-based CAPS score outperformed three other imaging-based scores for predicting outcomes after 3 months. The CAPS score could be implemented to inform patient selection for endovascular thrombectomy in basilar artery occlusions.