Relationship between the cortical evoked potential and local cortical blood flow following acute middle cerebral artery occlusion in the baboon

摘要: In most experimental studies of the effects ischemia on CNS electrical activity, produced has been total. The present experiments, however, were designed to establish quantitatively changes in activity corresponding different degrees cerebral ischemia. somatosensory evoked potential was measured at various sites exposed postcentral gyrus anesthetized baboon, and cortical blood flow assessed region electrode by highly focal method hydrogen clearance. technique middle artery occlusion used reduce over hemisphere. Following artery, amplitude typically diminished steadily a rate depending level residual local flow. depression (expressed units percent control per minute) significantly correlated with (r = −0.95, P < 0.001), which indicated linear relationship between these variables, regression line intercepting axis 15.2 ml/100g/min. data also strongly suggested threshold-type flow: If greater than about 16 ml/100g/min not affected, but flows less 12 abolished.