Effects of different mydriatics on the choroidal vascularity in healthy subjects

Purpose To evaluate choroidal vasculature changes after the instillation of mydriatic parasympatholytic and sympathomimetic agents in healthy subjects. Methods A total of 95 healthy subjects were enrolled in this prospective, randomized comparative study. Study participants were divided into three different groups depending on the drug to be administered: tropicamide (1%) group ( n  = 31), tropicamide (0.5%) + phenylephrine (10%) group ( n  = 30) and control group receiving artificial tears ( n  = 34). All participants underwent a complete ophthalmological examination including best corrected visual acuity, refractive status and axial length. Subfoveal choroidal thickness (CT), total choroidal area (TCA), luminal and stromal choroidal area (LCA and SCA) and choroidal vascularity index (CVI) were measured before and after eye drops instillation. Results All the baseline characteristics were matched between the three groups (all P  > 0.05). Before the mydriatic instillation, there were no significant differences of CT, TCA, LA, SCA, and CVI among the three groups (all P  > 0.05). After drug administration, CT, TCA, LCA, SCA, and CVI did not show any significant change as well (respectively, P  = 0.265; P  = 0.483; 0.573; P  = 0.405 and P  = 0.708). Conclusions Instillation of mydriatic eye drops did not induce significant changes of the choroidal vasculature, suggesting that their use do not alter CT and CVI evaluation.