# Association between first-year axial elongation and 10-year myopia progression in children wearing orthokeratology lenses: a ten-year longitudinal study

## TL;DR

This study shows that early changes in eye length in children wearing Ortho-K lenses can predict long-term myopia progression into adulthood.

## Contribution

The study introduces a predictive model using first-year axial elongation to forecast 10-year myopia outcomes in Ortho-K lens wearers.

## Key findings

- First-year axial elongation (Change AL) is a strong predictor of 10-year myopia progression.
- A cutoff of 0.28 mm in first-year elongation identifies children at risk of poor long-term control.
- Age-specific thresholds improve prediction accuracy for different age groups.

## Abstract

To investigate the correlation between first-year axial elongation and 10-year (adulthood) axial length (AL) outcomes in children wearing orthokeratology (Ortho-K) lenses, and to develop predictive models for long-term myopia control.

Data from 101 children who wore Ortho-K lenses for 10 years (2011–2025 cohort) were analyzed. Feature selection was performed using Single- and multi-factor logistic regression, LASSO, and the Boruta algorithm. Outcomes included AL > 26 mm after 10 years and rapid late-stage progression (annual increase >0.1 mm between years 9 and 10). Predictive models were visualized via dynamic nomograms.

First-year AL change (Change AL), baseline AL, and flat eccentricity (Flat E) were significant predictors for 10-year AL > 26 mm. The optimized model achieved an AUC of 0.952. A model only combining Chang AL predicted progression in years 9–10 with an AUC of 0.995. The optimal Chang AL cutoff for predicting stable 10-year progression was 0.28 mm overall (AUC = 0.978). Age-specific cutoffs were 0.28 mm for 8–9 years and 0.29 mm for 10–13 years.

The first-year treatment response is an important indicator of adult-stage and long-term myopia progression in Ortho-K wearers. Monitoring the 0.28 mm first-year elongation threshold enables early identification of children at risk of poor long-term control.