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Effects of Relative Corneal Refractive Power Changes on Relative Peripheral Refraction After Orthokeratology
Junchen Wang1, Wei Ma, Changxu Chen
1Department of Ophthalmology (J.W., W.M., C.C., B.Y., L.L.), West China Hospital of Sichuan University, Chengdu, Sichuan, China; Department of Optometry and Vision Science (J.W., W.M., C.C., B.Y., L.L.), West China School of Medicine, Sichuan University, Chengdu, Sichuan, China; and Laboratory of Optometry and Vision Sciences, Department of Ophthalmology (J.W., W.M., C.C., B.Y., L.L.), West China Hospital, Sichuan University, Chengdu, Sichuan, China.
Eye & Contact Lens
|January 23, 2026
Summary
Changes in corneal refractive power (CRP) can predict peripheral refraction changes in myopic children during orthokeratology. Nasal and inferior corneal changes correlate with temporal peripheral defocus, guiding myopia management.
Area of Science:
- Ophthalmology
- Optometry
- Corneal Refractive Surgery
Background:
- Orthokeratology is a myopia control method using reverse-geometry lenses.
- Understanding peripheral refraction changes is crucial for myopia progression management.
Purpose of the Study:
- To investigate the relationship between changes in summed relative corneal refractive power (CRP) and relative peripheral refraction (RPR) in myopic children undergoing orthokeratology.
- To identify predictors of peripheral refractive changes during orthokeratology treatment.
Main Methods:
- Prospective self-controlled study of 85 myopic children (8-12 years) fitted with orthokeratology lenses for 3 months.
- Corneal topography and peripheral refraction measured at baseline and 1, 3 months.
- Partial correlation and multiple regression analyses used to assess relationships between CRP and RPR changes.
Main Results:
- 78 participants completed the study.
- Changes in summed relative CRP within the central 5-mm zone correlated with RPR changes (r=-0.24 to 0.45).
- ΔSum5N (nasal quadrant CRP change) predicted ΔRPR-T (temporal RPR change) (adjusted R2=0.50).
Conclusions:
- Changes in summed relative CRP may predict peripheral refraction changes after orthokeratology.
- Regional corneal changes, particularly nasal and inferior, are associated with peripheral myopic shifts, especially temporally.
- Further research is needed to confirm these associations for myopia control strategies.
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