Morphological Changes in the Cornea Following Cessation of Long-Term Orthokeratology and Outcomes of SMILE Surgery: A Retrospective Comparative Analysis

By
Kun Zhou
Xiaohuan Ma
Di Shen
Wenjia Cao
Xiyu Sun
Mengchen Li
Wei Wei
February 13, 2026
0 min

Bmc Ophthalmology

Overview

This study investigates the corneal morphological changes after long-term orthokeratology (OK) lens wear and their impact on outcomes of small-incision lenticule extraction (SMILE) surgery. It finds that while corneal shape largely returns to baseline post-OK, subtle structural changes may persist, potentially affecting surgical outcomes.

Background

Myopia is a significant global public health issue, particularly in East Asia, where its prevalence has surged. Orthokeratology is a popular method for myopia control, but the long-term effects of lens wear on corneal morphology and subsequent surgical outcomes are not well understood. Understanding these effects is crucial as more individuals seek permanent refractive correction.

Data Highlights

Group	Number of Eyes	Average OK Wear Duration	Follow-Up Duration
OK Group	22	5.4 years	16.50 months
Control Group	22	N/A	11.27 months

Key Findings

Corneal stability was confirmed prior to SMILE surgery in the OK group.
Residual corneal flattening and increased astigmatism were observed after long-term OK lens wear.
Central corneal thickness and corneal volume were assessed at multiple time points.
Visual acuity outcomes post-SMILE were comparable between OK and control groups.
Long-term OK wear may lead to persistent corneal morphological changes affecting refractive surgery outcomes.

Clinical Implications

Clinicians should consider the potential for residual corneal changes in patients with a history of long-term orthokeratology when planning for refractive surgery. Individualized assessment of corneal stability and morphology is essential to optimize surgical outcomes.

Conclusion

The findings highlight the importance of understanding corneal changes following orthokeratology, as these may influence the outcomes of subsequent refractive surgeries like SMILE. Further research is warranted to establish standardized protocols for managing former OK users.