Cerebral blood flow evaluation of prolonged experimental vasospasm

Abstract

✓ Prolonged experimental cerebral vasospasm, determined by angiography, can be produced in animals by puncture of an intracranial artery (IAP) or subarachnoid injection of blood (SAI). Following these stimuli, several patterns of blood flow evolve. The biphasic pattern, seen only with hemorrhage from mechanical trauma to the vessel, seems to resemble most closely the clinical phenomenon. Presumably because of autoregulation, only angiographic constriction of cerebral arteries to less than one-half of their control value is associated with significant reduction of cerebral blood flow. Cerebral blood flow recordings and vessel caliber measurements should complement experiments in cerebral vasospasm to ascertain whether the spasm is producing significant ischemia and to assess the efficacy of subsequent treatment techniques.