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Updated: Apr 21, 2026
07:06
Binocular Dynamic Visual Acuity in Eyeglass-Corrected Myopic Patients
Published on: March 29, 2022
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Cone ratios in myopia and emmetropia: a pilot study
Nanyu Zhou1, David A Atchison, Andrew J Zele
1*MSc †DSc, FAAO ‡PhD School of Optometry & Vision Science and Institute of Health & Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland, Australia (all authors).
Summary
The study found no significant difference in the long wavelength-sensitive (LWS)-to-middle wavelength-sensitive (MWS) cone ratio between emmetropes and myopes. However, more myopia was linked to a lower LWS/MWS cone ratio in the peripheral retina.
Area of Science:
- Ophthalmology
- Retinal Physiology
- Visual Neuroscience
Background:
- Myopia is a common refractive error with complex etiology.
- The ratio of long wavelength-sensitive (LWS) to middle wavelength-sensitive (MWS) cones in the retina has been hypothesized to play a role in myopia development.
Purpose of the Study:
- To investigate the association between the LWS/MWS cone ratio and refractive error in young adults.
- To measure the LWS/MWS amplitude modulation ratio, an indicator of the cone ratio, in emmetropic and myopic individuals.
Main Methods:
- Multifocal visual evoked potentials (VEPs) were used to assess cone function.
- Silent substitution was employed to selectively stimulate LWS and MWS cone systems.
- Participants included 10 emmetropes and 20 myopes aged 22-33 years.
Main Results:
- No significant differences in LWS/MWS amplitude modulation ratios were found between emmetropic and myopic groups in either central or peripheral retinal regions.
- A trend suggested that greater myopia was associated with lower LWS/MWS ratios in the peripheral retina (13-30 degrees).
- Refractive error accounted for 16% of the variation in peripheral LWS/MWS ratios (p=0.02).
Conclusions:
- The findings do not strongly support a direct link between the LWS/MWS cone ratio and myopia in young adults.
- Further longitudinal studies are needed to determine if cone ratios predict myopia development over time.
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