Exogenous All-Retinoic Acid Induces Similar Longitudinal Changes in Ocular Biometry to Hyperopic Defocus in Mice.

Abstract

PURPOSE: This study aims to investigate the longitudinal changes in ocular biometry in mice treated with exogenous all-retinoic acid (atRA) and make comparisons with the lens-induced myopia (LIM) model. MATERIALS AND METHODS: Male C57BL/6J mice were administered 10&#x2009;&#xb5;l of atRA (1 milligram [mg]/milliliter [mL]) every other two daysperibulbar injection. The LIM group received monocular -30D lenses. Ocular biometrics were measured on Days 0, 3, 6, 10, and 15 using swept-source optical coherence tomography. Scleral thickness (ST) and retinal arc length (RAL) were measured on histological sections. RESULTS: Both exogenous atRA and negative lenses induced longer axial length (AL) from Day 3 and thinner retinal thickness (RT) from Day 6 (all&#x2009;<&#x2009;0.05). An increase in vitreous chamber depth (VCD) was noted from Day 3 in atRA-Treated (&#x2009;=&#x2009;0.001) eyes and from Day 6 in LIM-Treated eyes (&#x2009;<&#x2009;0.001). The interocular difference in lens thickness (LT) varied significantly over time (&#x2009;=&#x2009;0.004) in the atRA group. The LT to AL ratios (LT/AL) for atRA-Treated eyes were notably higher than those for the LIM eyes on Days 10 and 15 (all&#x2009;<&#x2009;0.05). The VCD to AL ratios (VCD/AL) were comparable between the two groups, with notable declines observed in the late stage (all&#x2009;<&#x2009;0.01). Additionally, both treatment groups showed similarly reduced ST and larger RAL than untreated eyes. CONCLUSIONS: Mice treated with exogenous atRA demonstrated comparable longitudinal ocular biometric alterations to the LIM model, except for the relatively thicker lenses.