Objective: We aimed to investigate whether tropicamide and phenylephrine eyedrops, which are routinely used for pupil dilation before fundus examination and optical coherence tomography angiography (OCTA), have effects on posterior segment vascular structures. Material and Methods: Firstly, OCTA evaluation was performed. Then, phenylephrine 2.5% drops were applied to the right eyes of the patients and tropicamide 0.5% drops were applied to the left eyes with phenylephrine 2.5% drops 3 times with 10 minutes intervals. OCTA was performed again. The differences between the vascular density values of both eyes before and after topical drop application were examined and compared statistically. Results: This is a prospective study evaluating 54 eyes of 27 patients. A statistically significant difference was observed in OCTA parameters -specifically superficial capillary plexus (SCP) total vascular density, SCP perifoveal vascular density, and SCP parafoveal vascular density- before and after drop instillation in eyes treated with topical phenylephrine (p=0.05, p=0.03, and p=0.033, respectively). Vascular densities after drop application were lower than before application. Conclusion: This study is the first to examine the results in 4 different groups by administering topical phenylephrine to one eye and topical phenylephrine and tropicamide drops to the other eye. From our point of view, topical phenylephrine reduces macular vascular density values due to its vasoconstriction effect. We also think that topical tropicamide minimally increases macular vascular density values due to its partial vasodilation effect.
BOZDOĞAN et al. (Thu,) studied this question.