This clinical trial will test the hypothesis that correcting a specific group of myopic children with bifocals, instead of with single-vision spectacles, will reduce the rate of myopic progression. The specific group of myopic children to be included in the trial are those who show near-point esophoria, a tendency to over-converge while reading. Such children constitute about 30 percent of all myopic children. Support for the effectiveness of bifocals in esophoric children comes from three sources: a retrospective study, a secondary analysis of a clinical trial designed for another purpose, and pilot data collected by the applicants. These studies suggest that bifocals reduce the rate of myopic progression by 50 percent in esophoria children. The proposed study will be the first clinical trial of bifocals in myopic children with esophoria. Eighty myopic children with near-point esophoria will be divided randomly into two treatment groups: correction with single-vision lenses or with bifocal lenses containing a +1.50 D add. For 30 months, myopia will be measured every 6 months by means of automated, cycloplegic refraction. The long-term objective of the study is to find a method of reducing the final amount of myopia in a significant portion of all myopic persons. About 25 percent of all Americans are myopic. The correction of myopia and the treatment of myopia-associated diseases accounts for a significant proportion of health care costs. Substantial savings could be achieved if this study is successful. Many children, who are in phase of rapid myopia progression, would have to change prescriptions less often. Many adults would have better vision without glasses, thinner lenses, and a lower risk of retinal detachment.
