Related Experiment Video
Updated: May 13, 2026
05:46
Correction of Presbyopia by Monocular Bi-Aspheric Ablation Profile
Published on: September 20, 2024
Refractive changes from hyperopic orthokeratology monovision in presbyopes
Paul Gifford1, Helen A Swarbrick
1School of Optometry and Vision Science, University of New South Wales, Sydney, New South Wales, Australia. p.gifford@unsw.edu.au
Summary
Hyperopic orthokeratology (OK) effectively corrects near vision in emmetropic presbyopes by steepening the central cornea and flattening the mid-periphery. This overnight lens wear provides a functional monovision correction for near tasks.
Area of Science:
- Ophthalmology
- Optometry
- Corneal Physiology
Background:
- Presbyopia, the age-related loss of accommodation, affects near vision.
- Emmetropic presbyopes often seek solutions for functional near vision without refractive correction.
- Orthokeratology (OK) is a non-surgical refractive correction method using specialized contact lenses.
Purpose of the Study:
- To evaluate the refractive and corneal topographic changes induced by overnight hyperopic orthokeratology (OK) in emmetropic presbyopic individuals.
- To determine the time course and retention of these changes over a 7-day wear period.
Main Methods:
- A prospective study involving 16 adult emmetropic presbyopes, with one eye fitted with hyperopic OK lenses (+2.00 D).
- The fellow eye served as a non-lens-wearing control.
- Refractive and corneal topographic measurements were taken at baseline, morning (A.M.) after lens removal, and evening (P.M.) 8 hours post-removal over 7 days.
Main Results:
- Hyperopic OK induced a significant myopic shift in refraction (up to -1.11 D) and improved near visual acuity (from Jaeger 10.8 to 3.2).
- Central corneal steepening and paracentral nasal corneal flattening were observed, with effects persisting for up to 8 hours post-removal by Day 7.
- Binocular distance visual acuity remained unchanged, indicating a monovision effect.
Conclusions:
- Overnight hyperopic orthokeratology successfully induces central corneal steepening and paracentral flattening, creating a myopic shift for functional near vision correction.
- This method offers a viable monovision correction option for emmetropic presbyopia without compromising distance vision.
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