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Peripheral defocus with spherical and multifocal soft contact lenses
David A Berntsen1, Carl E Kramer
1*OD, PhD, FAAO †BA College of Optometry, University of Houston, Houston, Texas.
Summary
This study compared peripheral defocus in myopic eyes using spherical versus multifocal contact lenses. Multifocal lenses induced more peripheral myopic defocus, suggesting potential for myopia control in children.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- Myopia, or nearsightedness, is a growing global health concern.
- Understanding peripheral defocus is crucial for developing myopia control strategies.
- Soft contact lenses are a common method for vision correction.
Purpose of the Study:
- To compare peripheral defocus profiles in myopic eyes corrected with spherical versus center-distance multifocal soft contact lenses.
- To evaluate defocus at distance and near viewing conditions.
Main Methods:
- Twenty-five young adults with myopia participated.
- Refractive error was measured with spherical and multifocal contact lenses.
- Measurements were taken centrally and peripherally at various angles for distance and near tasks.
Main Results:
- Multifocal lenses created significantly more myopic defocus peripherally at distance compared to spherical lenses.
- At near, multifocal lenses also resulted in more myopic peripheral defocus.
- Spherical lenses induced peripheral hyperopic defocus, while multifocal lenses approached peripheral emmetropia at some locations.
Conclusions:
- Center-distance multifocal contact lenses induce peripheral myopic defocus during distance viewing.
- Multifocal lenses offer relatively less hyperopic peripheral defocus compared to spherical lenses during near viewing.
- The observed defocus profiles suggest multifocal lenses are suitable for investigating myopia progression in children.
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