Comparison of cyclopentolate versus tropicamide on corneal topography in emmetropic and myopic eyes

Abstract

Background: To compare the effect of cyclopentolate versus tropicamide eye drops on anterior surface corneal parameters using Keratograph 4 in myopic and emmetropic individuals.Methods: Fifty-eight participants included 29 emmetropic and 29 myopic individuals, were recruited, according to inclusion and exclusion criteria. At baseline visit, anterior surface corneal parameters were measured using Keratograph 4 Keratograph 4in the right eye. All measurements were repeated at two separate visits, one week apart, after administration of tropicamide 1% and cyclopentolate 1% at similar conditions.Results: Of 58 participants who completed the study, 29 (24 women, 5 men, age: 23.82± 2.78 years) were emmetropic and 29 (21women, 8 men, age: 23.66± 2.76 years) were myopic. Baseline mean spherical equivalents were -0.23±0.23 D and -2.45±1.03 D in emmetropic and myopic groups, respectively. The analysis of the data showed a significant hyperopic shift following instillation of both cycloplegic eye drops in both refractive groups. However, tropicamide results was statistically insignificant in comparison with cyclopentolate (p=0.49). The assessment of data revealed no statistically significant differences in anterior surface corneal parameters in baseline, tropicamide and cyclopentolate instillation in each refractive group, except IHD value with tropicamide in myopic group (p=0.02). The further analysis between refractive groups also showed no significant differences in anterior surface corneal parameters in each session.Conclusions: Present study indicates that cyclopentolate and tropicamide do not appear to affect corneal topographic parameters and hence can be trusted to capture topography data.