Investigation of the short-term effects of water drinking test on the eye using optical coherence tomography angiography in young healthy male subjects

Abstract

Purpose To evaluate the acute effects of the water drinking test (WDT) on the eye using optical coherence tomography angiography (OCTA) on healthy young male subjects. Methods The study included 25 eyes of 25 male subjects. Selected parameters of the retinal vasculature were measured, including macular flow indices, foveal avascular zone, and vessel densities (VDs) of the macula using OCTA. The measurements were taken on the first day without drinking water at 0 min, 30 min and 60 min, then repeated on the second day before drinking water at 0 min, and after drinking water at 30 min and 60 min. The Paired Samples t-test and repeated measures One-way analysis of variance test were used in the statistical analyses. Results The repeated measures analysis of variance test using Bonferroni adjustment demonstrated a significant increase in superficial and deep foveal VD following WDT (p < 0.001 for both). Intraocular pressure, retinal nerve fibre layer thickness, foveal avascular zone, flow area of choriocapillaris, flow area of outer retina, foveal non-flow area of superficial layer, and retinal thickness measurements showed no significant changes following WDT. Conclusions WDT is associated with temporary flow modifications in superficial and deep foveal vascular plexus in young male subjects.