This proposal is for The OSU College of Optometry Clinic Site to conduct the Soft Bifocal Contact Lens Myopia Control Study, a randomized clinical trial designed to address whether and by what mechanism commercially available soft bifocal contact lenses may slow eye growth in myopic children. Experimental animal data and numerous but scientifically limited human clinical evaluations suggest that contact lenses that alter peripheral defocus may slow the progression of myopia.
The first aim i s to conduct a rigorous prospective randomized clinical trial 'to determine if bifocal contact lenses that supply peripheral retinal myopic defocus slow myopia progression in children in a dose-dependent manner as a function of add power.
The second aim i s to evaluate whether peripheral myopia is a visual signal for eye growth by determining whether the rate of progression follows a dose-dependent response to peripheral myopic retinal defocus.
The final aim i s to determine the structural correlates of any slowing of myopia progression: is any slowing of eye growth local and peripheral, foveal, global, or confined to one more ocular quadrants. Analyses related to the second and third aims will determine how soft bifocal contact lenses affect growth of the eye and, ultimately, to optimization of the visual signals that slow myopia progression in children. In this trial, 294 children aged 7 to 11 years with myopia will be randomly assigned to wear soft bifocal contact lenses (Biofinity Multifocal with +1.50 add or +2.50 add;Cooper Vision, Fairfield, NY) or single vision contact lenses (Biofinity;Cooper Vision, Fairfield, NY). The primary outcome measure is change in cycloplegic spherical equivalent auto refraction over three years. Secondary outcomes are central and peripheral eye length. Covariates include the amount of peripheral defocus at distance and near while wearing a contact lens, distance peripheral refractive error without a contact lens, high and low contrast visual acuity at distance, high contrast near visual acuity, accommodative lag, pupil size, family refractive error history, a myopia risk factor survey, vision-specific quality of life, and contact lens wear compliance.
Myopia affects approximately one-third of people in the United States, and approximately 60% (60 million) of them become myopic during childhood. The results of this study have the potential to affect the standard of care for young myopic children, and the results will lead to important information regarding optimization of the visual signals that may lead to slower eye growth and myopia progression.