Regional cerebral blood flow studies in subarachnoid hemorrhage

Abstract
✓ Regional cerebral blood flow (rCBF) studies using the intra-arterial 133xenon method were performed on 10 patients with subarachnoid hemorrhage. Both preoperative and postoperative studies showed evidence of decreased flow in the entire hemisphere studied, and, in addition, evidence of focal ischemia, focal hyperemia, focal vasoparalysis, and often global impairment of autoregulation. The degree of flow abnormalities correlated well with the clinical grading of the neurological deficit. It is suggested that analysis of the state of autoregulation might be useful in determining the time for surgical intervention and that rCBF studies are important in defining the effects of drugs used to counteract the ischemic effects of spasm.