LIGHT-EVOKED CHANGES IN POSTERIOR CEREBRA L-ARTERY BLOOD-FLOW

In 20 healthy volunteers light evoked changes in blood flow of the pos terior cerebral artery were studied with color coded Doppler sonograph y. Doppler flow profiles of the PCA were recorded before, during and a fter exposition with light. Under the treatment with light the RI decr eased in the mean fom 0.61 down to 0.50, indicating an increase of flo w. After redarking the RI increased again up to a mean of 0.62. The ap plied test could be a helpful tool to clarify the pathophysiological m echanism in defect seeing.