Cerebral vasospasm model produced by subarachnoid blood injection in dogs.

Subarachnoid hemorrhage (SAH) was simulated in dogs by injecting blood into the cisterna magna. Time-dependent development of spasm of the basilar artery was angiographically determined. One week after SAH, the diameter of the basilar artery decreased by 15.5 +/- 5.4% and 46.4 +/- 3.0% in the single and double injection model, respectively. Thereafter, the artery diameter gradually returned to normal. The time course of diameter changes in the double injection model resembles that seen in the clinical setting, and the double injection model seems to be useful for the experimental study of cerebral vasospasm.