Cerebral Blood Flow

TWENTY years ago Drs. Seymour Kety and Carl Schmidt first described the inert-gas technic for the quantitative measurement of cerebral blood flow. Conceived and developed in the Pharmacology Laboratory of the University of Pennsylvania and carried out on the wards of the Philadelphia General Hospital, the nitrous oxide method was first reported in 1945 in the American Journal of Physiology. 1 Since then, and on the basis of this method, a remarkable number of data have accumulated on the physiology of the cerebral circulation. Normal brain metabolism has been elucidated, along with alterations produced by drugs and disease.2 , 3 In the ensuing . . .