Abstract WP123: Accuracy of Cisternal Score in Predicting Cerebral Vasospasm Risk in Aneurysmal Subarachnoid Hemorrhage: A Post Hoc Analysis of a Single Center Study

Abstract

Background: Cisternal score (CISCO), which is calculated based on quantification of blood clot in basal cisterns, has been shown to have good accuracy in predicting ventriculoperitoneal shunt requirement in patients with aneurysmal subarachnoid hemorrhage (aSAH). We hypothesized that CISCO is superior to modified Fisher score (mFS) in predicting vasospasm, a common complication associated with worse outcomes in aSAH, as it better quantifies blood clot burden in the basal cisterns. Design/Methods: We performed a post hoc analysis of a retrospective study of a cohort of consecutive patients with aSAH admitted to an academic center from 2016 through 2021. Data was collected prospectively as part of a quality improvement project. Cerebral vasospasm was defined based on transcranial Doppler criteria. CISCO, as previously described, was constructed based on quantification of blood clot thickness in the basal cisterns (interpeduncular, ambient, crural, prepontine, interhemispheric cisterns, and bilateral Sylvian fissures) on admission head CT scans. Receiver operating characteristics (ROC) curve analysis was performed to compare accuracy of CISCO with mFS in predicting vasospasm. Results: We included 176 patients with aSAH who had radiographic assessments with complete clinical data. Mean age was 54.9 years [SD 12.8] and 57% were female. Cerebral vasospasm was observed in 30% of patients. CISCO ranged from 0 to 10 with a median of 3 [IQR 1-5]. Higher CISCO was associated with higher risk of vasospasm (odds ratio 1.29 per point increase, 95% CI 1.17-1.49; p=0.001). ROC curve analysis revealed that CISCO had higher accuracy in predicting vasospasm compared to mFS but the difference was not significant (AUC 0.67, 95% CI 0.59-0.76 vs 0.60, 95% CI 0.52-0.68; p=0.10). Conclusions: CISCO has comparable accuracy with mFS score in predicting vasospasm in aSAH. Improvement in quantification methods using fully automated volumetric measurement techniques may further enhance its accuracy in predicting vasospasm in aSAH in future. Larger studies are needed to test this hypothesis and to explore the utility of using CISCO in clinical practice.