Purpose: To study the long-term effect of topically applied 0.12% isopropyl unoprostone (unoprostone, Rescula) on microcirculation in the ocular fundus.
Materials and methods: Using a laser speckle tissue circulation analyzer, normalized blur (NB), a quantitative index of blood flow velocity and tissue blood flow, was measured in the optic nerve head (ONH) and choroid-retina before and 4.5 hours after an instillation of placebo into both eyes in 11 normal human volunteers. Intraocular pressure (IOP), blood pressure, and pulse rate were also measured. A drop of unoprostone or the placebo was instilled into each eye in a double-blind manner twice a day for 21 days (the treated or untreated eye).
Results: Twenty-one days later, NB values in the ONH and the choroid-retina increased significantly and the IOP decreased significantly only in the treated eyes. Ocular perfusion pressure showed no significant changes.
Conclusions: These results suggest that the increase of the blood flow in the microcirculation in the human ocular fundus following the relatively long-term topical application of unoprostone may be due to reduction in vascular resistance.