# Crystalline Lens Thickness Changes in Myopia Children During Long‐Term Orthokeratology Treatment

## TL;DR

This study examines how wearing orthokeratology lenses affects eye growth in children with myopia over two years.

## Contribution

The study identifies crystalline lens thickness changes as a novel factor linked to reduced axial length elongation in children using orthokeratology.

## Key findings

- Crystalline lens thickness (CLT) and axial length (AL) increased significantly after two years of orthokeratology treatment.
- Greater baseline spherical equivalent and increased CLT were associated with reduced AL elongation.
- Anterior chamber depth remained stable during the treatment period.

## Abstract

To investigate ocular parameters associated with axial length (AL) growth in children wearing orthokeratology lens during 2 years of follow‐up.

This is a retrospective study. Medical records of 46 patients who underwent orthokeratology treatment for 2 years were reviewed. Baseline variables included age at initiation of orthokeratology wear, spherical equivalent (SE), central corneal thickness (CCT), and the flat and steep keratometry of corneal principal meridians. The changes in anterior chamber depth (ACD) and crystalline lens thickness (CLT) were also analyzed. The contributions of all variables to the AL elongation were assessed using univariate and multivariate regression analyses.

CLT and AL significantly increased after 2 years of orthokeratology wear compared with baseline (both p < 0.01), whereas ACD did not significantly change compared with baseline (p = 0.301). Univariate analyses showed that a reduced rate of AL elongation was found in children who were older age (p = 0.02), had greater SE (p = 0.026), thicker CCT at baseline (p = 0.027), and more increase in CLT (p = 0.019) in 2 years. Furthermore, greater SE at baseline and more increase in CLT were associated with less elongation of AL during 2 years of follow‐up in multivariable analyses (p = 0.044 and 0.034).

CLT was significantly increased in the first year and keep stable in the second year in children with orthokeratology wearing. Greater baseline SE and more increase in CLT were associated with less elongation in AL during orthokeratology wear.