The Effect of Ocular Hypotensive Medications on Posterior Segment Blood Flow in Healthy Subjects: A Prospective, Randomized, and Interventional Study.

Abstract

Purpose: To evaluate the immediate impact of topical ocular hypotensive medications on peripapillary and macular blood flow in healthy adults from Northeast Iran.

Methods: A prospective, randomized, and interventional study was conducted on 80 healthy volunteers, with each volunteer having one eye treated with either brimonidine, dorzolamide, latanoprost, or timolol, all of which are ocular hypotensive medications. The study included a placebo treatment for one eye of each participant to serve as a control. At the peak effect of the drugs, all participants underwent an optical coherence tomography angiography scan of their eyes. A total of 160 eyes were included in the study.

Results: According to the findings, the use of ocular hypotensive drugs did not demonstrate any significant influence on the radial peripapillary capillary network. However, the results indicated that a single dose of dorzolamide could result in a significant increase in macular blood flow (P = 0.019). Conversely, treatment with timolol resulted in a significant decrease in macular blood flow (P = 0.002). Moreover, brimonidine significantly affected the thickness of the retinal nerve fiber layer (P = 0.02).

Conclusions: According to our findings, dorzolamide was the most effective in enhancing young adults' full macular thickness and macular blood flow. Conversely, timolol treatment was found to decrease the macular blood flow, which in turn may cause visual field defects due to optic nerve head and macular ischemia in patients with low-tension glaucoma.