Abstract
Purpose: :
Several recent studies have delineated the time course of emmetropization in normal infants, but little is known about emmetropization in children with infantile esotropia (ET). For normal infants, more hyperopia is associated with faster emmetropization during infancy. In infantile ET, about 75% of infants have mild to moderate hyperopia; some are prescribed spectacle correction during infancy, preschool years, or later childhood. Here we examine time course of emmetropization in children with infantile ET from initial diagnosis to 12 years of age.
Methods: :
143 consecutive infants with infantile ET and follow-up for 5 to 12 years were enrolled. Cycloplegic refraction, clinical evaluation, and treatment data were collected from medical records.
Results: :
At the time of initial diagnosis, 6% of infants had myopic refractive errors, 55% had 0.00 to +2.99D, 27% had +3.00 to +4.99D, and 13% had ≥+5.00D; 9% had anisometropia ≥1.00D. The mean spherical equivalent (SE) at 3 months was +2.88±1.76D, about 0.8D greater than normal infants (Mayer et al., 2001). At 9 months, there was little change in mean SE for infantile ET (+3.25±2.15D), while normal infants emmetropize to a mean SE of +1.36D by the same age. Children with infantile ET remained significantly hyperopic through 7 yrs of age (mean SE at 7 yrs = +3.18±1.78D). After 7 yrs, there was rapid emmetropization so that, by age 11-12 yrs, the mean SE was +1.00±2.22D. Children with higher refractive errors who wore spectacles showed approximately the same change in refractive error between 7 and 12 years of age as those with lower refractive errors. There was no evidence that undercorrecting hyperopia after age 6 or 7 yrs sped its resolution. The prevalence of anisometropia was relatively stable throughout follow-up, although some cases resolved while new cases developed, including 10 new cases that first presented after 5 yrs of age.
Keywords: esotropia and exotropia • emmetropization • hyperopia