Prognostic Value of Cerebral Perfusion-Computed Tomography in the Acute Stage After Subarachnoid Hemorrhage for the Development of Delayed Cerebral Ischemia

BACKGROUND AND PURPOSE: Delayed cerebral ischemia (DCI) is an important cause of death and disability after subarachnoid hemorrhage. We studied the additional prognostic value of brain perfusion to 3 established predictors (age, clinical condition on admission, and amount of subarachnoid blood) for the development of DCI. METHODS: We included 69 patients scanned with perfusion--computed tomography within 72 hours after subarachnoid hemorrhage. For each patient, we determined cerebral blood flow (CBF) ratios of prespecified opposite regions of interest and the 3 established predictors. We calculated adjusted hazard ratios (HRs) for the CBF ratio and the 3 established predictors by means of multivariate analysis (Cox regression). The additional prognostic value of CBF ratios was assessed by comparing the area under the receiver operating characteristic curve (AUC) of 2 models: 1 with and 1 without addition of the CBF ratio to the 3 established predictors. RESULTS: The CBF ratio was an independent predictor for the development of DCI (HR, 0.63; 95% CI, 0.46 to 0.86) as was clinical condition (HR, 1.47; 95% CI, 1.01 to 2.13). By adding the CBF ratio to the model with the 3 established predictors, the AUC of the receiver operating characteristic curve increased from 0.76 (95% CI, 0.65 to 0.89) to 0.81 (95% CI, 0.71 to 0.91). This trend toward an increased AUC suggests an improved predictive value. CONCLUSIONS: The CBF ratio is an independent predictor for the development of DCI and can contribute to a better identification of patients at high risk for DCI.