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Updated: Jul 1, 2026
07:06
Binocular Dynamic Visual Acuity in Eyeglass-Corrected Myopic Patients
Published on: March 29, 2022
Visual acuity and "balanced progressive" simultaneous vision multifocal contact lenses.
Elizabeth Sanders1, Heidi Wagner, Lewis N Reich
1College of Optometry, Health Professions Division, Nova Southeastern University, Fort Lauderdale, FL 33328, USA.
Eye & Contact Lens
|September 10, 2008
Summary
Add power in multifocal contact lenses minimally impacts distance visual acuity under ideal lighting and high contrast. However, reduced contrast or dim light conditions significantly decrease visual acuity with higher add powers.
Area of Science:
- Ophthalmology
- Optometry
- Vision Science
Background:
- Multifocal contact lenses (MCLs) are designed to correct vision at multiple distances.
- Understanding the impact of lens parameters on visual acuity is crucial for patient satisfaction and effective vision correction.
Purpose of the Study:
- To evaluate the effect of varying add power in simultaneous vision, balanced progressive MCLs on distance visual acuity.
- To determine how light levels and contrast influence this relationship.
Main Methods:
- Twenty-five young subjects with normal vision were fitted with CooperVision Proclear Multifocal contact lenses.
- Distance visual acuity was measured using a Bailey-Lovie chart under photopic and mesopic light levels with high and low contrast, across four add powers (+1.00 to +2.50).
Main Results:
- Distance visual acuity remained above 20/20 under high contrast, photopic conditions for all add powers.
- Significant decreases in visual acuity were observed under low contrast (photopic) and high/low contrast (mesopic) conditions as add power increased.
- Pupil diameter varied significantly between photopic (3.9 mm) and mesopic (6.2 mm) conditions.
Conclusions:
- The add power of MCLs has a minimal effect on distance visual acuity in high-contrast, well-lit environments.
- Visual acuity significantly degrades with increasing add power under reduced illumination and lower contrast conditions.
- Clinical fitting should consider environmental factors like lighting and contrast to optimize MCL performance.
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