The effect of arterial PO2 on relative retinal blood flow in monkeys.

The relationship of blood oxygenation to retinal blood flow has been studies in rhesus monkeys. Constriction of major retinal arteries and veins during hyperoxia and dilation during hypoxia are demonstrated. Together with mean circulation times based on the technique of fluorescein densitometry curves, these data allow an estimation of retinal blood flow, which increases considerably in hypoxia and shows a moderate decrease in hyperoxia. These findings indicate that the retinal circulation parallels that of the brain in adjusting to changes in arterial PO2 with compensatory changes in blood flow.