The effect of 0.5% tropicamide/0.5% phenylephrine mixed eye drop in Chinese adults with myopia and its inter-eye difference in refractive outcomes

Abstract

Objective:

To evaluate the effect of 0.5% tropicamide/0.5% phenylephrine mixed eye drop and make the inter-eye comparison of refractive outcomes in Chinese adults with myopia.

Methods:

Refractive measurements were performed without cycloplegia and repeated 30 minutes later with 0.5% tropicamide/0.5% phenylephrine mixed eye drop (Mydrin-P) on 341 myopic adults. Vector analysis was used to analyze the data. Changes of spherical equivalent (M) and astigmatism for both J₀ and J₄₅ components between these two refractions were calculated as Error_M, Error_J₀ and Error_J₄₅. Inter-eye correlations were studied. The inter-eye difference after cycloplegics were described as Diff M, Diff J₀ and Diff J₄₅. The effect of anisometropia, age and the higher order aberrations (HOAs) on inter-eye differences toward the cycloplegic agent were analyzed.

Results:

Difference was found only for the Error_J₄₅ component between the two eyes (p = 0.0040). Pearson correlation coefficients between the two eyes for Error_M, Error_J₀, and Error_J₄₅ were 0.3140 (p < 0.0001), 0.1464 (p = 0.0068), and 0.0099 (p = 0.8558), respectively. The inter-eye differences (Diff) in response to cycloplegic agent increased with the amount of anisometropia. The oldest group had the highest Diff M values. However, HOAs were found not to be related to the inter-eye differences.

Conclusions:

Accommodation was still relaxed by tropicamide/phenylephrine eye drops in myopic adults. The changes of refraction due to cycloplegia were not well correlated between the two eyes in myopic patients. Anisometropia and ocular dominance might be an important factor for the inter-eye difference.

Keywords::

• Anisometropia
• Cycloplegia
• Myopia
• Ocular dominance
• Refraction
• Vector analysis

Transparency

Declaration of funding

This work was supported by the National Natural Science Foundation of China (81100653) and by Grants 201302015 from the National Health and Family Planning Commission of the People's Republic of China.

Declaration of financial/other relationships

X.Z., M.C., J.D., and Y.L. have disclosed that they have no significant relationships with or financial interests in any commercial companies related to this study or article.

CMRO peer reviewers may have received honoraria for their review work. The peer reviewers on this manuscript have disclosed that they have no relevant financial relationships.

Notes

*Mydrin-P is a registered trade name of Santen, Osaka, Japan

†Mydrin-P is a registered trade name of Santen, Osaka, Japan