Long-term effect of topically applied isopropyl unoprostone on microcirculation in the human ocular fundus.

PURPOSE To investigate the long-term effect of 0.12% isopropyl unoprostone (Rescula) on microcirculation in the human ocular fundus. METHODS A laser speckle tissue circulation analyzer was used to measure normalized blur (NB), a quantitative index of blood flow velocity, in the optic nerve head (ONH) and choroid-retina before and 4.5 hours after the instillation of a placebo into both eyes of 11 healthy volunteers. The intraocular pressure (IOP), blood pressure, and pulse rate were also recorded in this control experiment. Thereafter, a drop of unoprostone or a placebo was instilled into each eye in a double-blind manner twice a day for 21 days to form treated and untreated groups. RESULTS After 21 days, the NB values in the ONH and choroid-retina had increased significantly and the IOP had decreased significantly in the unoprostone-treated eyes. Ocular perfusion pressure showed no significant change. CONCLUSIONS These results suggest that long-term application of unoprostone can increase microcirculatory blood flow in the human ocular fundus, probably due to a reduction in vascular resistance.