The effect of topical l-epinephrine on regional ocular blood flow in monkeys

A 25 microliter volume of a 1-% l-epinephrine borate solution applied on the cornea of one eye in 12 monkeys reduced blood flow through the iris and the ciliary body by 59% and 20%, respectively, compared to the untreated control eyes. In the ciliary body the main effect was in the ciliary processes. Blood flow was determined with the labeled microsphere method 1, 4, and 6 hr after application of the drug. The average blood flow reductions were of the same order in the three groups, indicating a duration of at least 6 hr. No effect on blood flow through the retina or the choroid was observed.