Visual acuity, amblyopia, and ocular pathology in 12-to 13-year-old children in northern Mexico

Purpose: The aim of this study was to establish visual acuity (VA) and the prevalence of amblyopia and other ocular disorders in a population of 12- to 13-year-old children in Mexico who have not been vision screened. Methods. A total of 1,035 12- to 13-year-old children were examined in a field study. The examination included VA, stereopsis, cover testing, refractive retinoscopy, and examination of the red reflex and posterior pole. In cases with unexplained subnormal VA, visually evoked potential/visually evoked response was also performed. Results. A greater than or equal to20/20 in at least one eye was found in 93% of the subjects. Bilateral VA less than or equal to20/40 was found in 0.3% of cases. None of the subjects had bilateral VA <20/60. Amblyopia (less than or equal to20/40) was found in 26 subjects (2.5%). In 10 cases, the cause of subnormal VA was unexplained. Ocular albinism was found in 3 cases whereas strabismus was found in 24 subjects (2.3%). There were very few ocular opacities or posterior pole abnormalities. Conclusions:The visual status in the Mexican 12- to 13-year-old children tested was good. The prevalence of amblyopia was similar to that in other unscreened populations.