Cyclorefraction of healthy children in the first two years of life

Objectives: To provide a description of refractive errors in healthy, term-born children, aged 1 through 24 months, and to test the hypothesis that spherical equivalent becomes significantly less hyperopic and less variable with increasing age. Methods: This is a prospective, cross-sectional design, cycloplegic retinoscopy was used to measure the refractive error in both eyes of 100 healthy, term- born children in four age groups. Spherical equivalent, cylindrical power and axis were analyzed as a function of age. Results: Spherical equivalents of right and left eyes did not differ at any age. Hyperopia declined significantly with increasing age. The variability in spherical equivalent also decreased significantly with age. Cylindrical error of one diopter or more was found in 15% of children; the proportion with astigmatism was highest in infancy and then waned. Myopia and anisometropia were rare, occurring in 5% and 2% of the sample, respectively. Conclusions: Significant declines in hyperopia and variability of spherical equivalent appear to be features of emmetropization. The normal prediction limits provide guidelines against which data from individual patients can be compared.