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Binocular Dynamic Visual Acuity in Eyeglass-Corrected Myopic Patients
Published on: March 29, 2022
Changes in accommodative and vergence responses when viewing through near addition lenses
Bai-Chuan Jiang1, Yin C Tea, Derek O'Donnell
1College of Optometry, Nova Southeastern University, Ft. Lauderdale, Florida 33328, USA. bjiang@nova.edu
Optometry (St. Louis, Mo.)
|February 27, 2007
Summary
Near addition lenses significantly alter accommodative response and near phoria in both emmetropic and myopic individuals. These lenses reduce accommodative lag, potentially impacting myopia progression.
Area of Science:
- Ophthalmology and Optometry
- Vision Science
Background:
- Near addition lenses are hypothesized to reduce accommodative lag and potentially slow myopia progression.
- Understanding the impact of these lenses on visual function is crucial for myopia management strategies.
Purpose of the Study:
- To investigate the differences in accommodative response and near phoria in subjects using near addition lenses compared to those without.
- To analyze these differences across both emmetropic and myopic individuals.
Main Methods:
- Monocular and binocular accommodative responses were measured using a Canon R-1 optometer with and without +2.00 diopter (D) lenses.
- Near dissociated phoria was assessed using Maddox rod, cover test, and Von Graefe techniques.
- Fourteen subjects (7 emmetropic, 7 myopic) participated in the study.
Main Results:
- Significant differences (P < 0.0001) were observed in accommodative response and near phoria with and without near addition lenses.
- Average accommodative response decreased substantially when using +2.00 D lenses (monocular: 0.60 D, binocular: 0.77 D) compared to no lens (monocular: 2.03 D, binocular: 2.11 D).
- Near phoria shifted significantly towards esophoria when using near addition lenses (-7.90 PD) compared to without (-2.08 PD).
Conclusions:
- Near addition lenses markedly alter accommodative response and near phoria.
- The study found no significant differences in these responses between refractive error groups.
- An increase in vergence accommodation is proposed as the cause for the observed differences between binocular and monocular accommodation with near addition lenses.
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