Retrospective analysis of predictors of cerebral vasospasm after ruptured cerebral aneurysm surgery: influence of the location of subarachnoid blood

The amount of blood on computed tomography (CT) has been shown to be a predictor of cerebral vasospasm after subarachnoid hemorrhage (SAH). However, the influence of the location of the blood on the incidence of vasospasm remains unclear. We retrospectively assessed the association of the blood volumes in the individual components (cisterns and fissures) of CT scans with angiographic vasospasm after SAH. One hundred forty-nine SAH patients scheduled for cerebral aneurysm clipping were enrolled. The amount of subarachnoid blood was classified using the Fisher CT grade . The amounts of subarachnoid blood in 5 cisterns or 3 fissures were also evaluated using SAH scores ranging from 0 to 3 (0, no blood; 3, completely filled with blood). Cerebral vasospasm was diagnosed by the results of angiography. Angiographic vasospasm developed in 51 of 149 patients (34%). Of those, 26 patients were symptomatic. The Fisher CT grade and SAH scores in the right and left sylvian fissures and suprasellar cisterns were significantly higher in patients with angiographic vasospasm than in those without it. Univariate logistic regression analysis revealed that a high Fisher CT grade and high SAH scores in the right and left sylvian fissures and suprasellar cisterns were predictors of angiographic vasospasm. Multivariate analysis indicated that the SAH score in the right sylvian fissure was an independent predictor of angiographic vasospasm (odds ratio, 3.6; 95% confidence interval (CI), 1.7-7.7; P = 0.01). The results indicated that the amount of blood in the right sylvian fissure was significantly associated with the development of angiographic vasospasm after SAH.