Abstract
Purpose:
Children with infantile esotropia fail to emmetropize during the first year of life and retain their moderate hyperopia until age 7 years, after which they experience significant decreases in hyperopia at 8-12 years (Birch et al Eye 2010). These data suggest a dissociation between the mechanisms that guide eye growth during infancy and later childhood. Here we further investigate this dissociation by examining and the longitudinal changes of refractive error in children with accommodative esotropia (AccET).
Methods:
Refractive error data of children with AccET from Indiana University and the Retina Foundation of Southwest were analyzed retrospectively. Eligibility criteria included: hyperopia ≥ +4.00 D, initial cycloplegic refraction before 4 years of age and at least once between age 7 and 12 years. Refractions from medical records were converted into spherical equivalent (SEQ) in units of diopters (D). SEQ from two groups were analyzed: infantile AccET (N=19; onset <12 months) and late-onset AccET (N=118; onset >18 months).
Results:
Infantile and late-onset groups had different developmental changes in refractive error. Infantile AccET refractive error SEQ were best fit with a bi-linear spline model: y1=6.34-0.07*Age when Age ≤ 7 years; y2=9.23-0.48* Age when Age>7 years. The rate of change in later childhood is significantly higher (p <0.001) than during infancy; before the age of 7 years, the rate of change is -0.07D/year and after age 7 years, the rate of change is -0.48D/year. Late-onset AccET SEQ was best fit with a linear model: y=5.9-0.0005*Age, showing little change with age (p=0.81).
Conclusions:
Children with infantile AccET experience prolonged hyperopia followed by a significant myopic shift after 7 years of age, consistent with a dissociation between infantile and school age myopic shifts. In contrast, children with late-onset AccET have no significant decrease in hyperopia between 1.5 and 12 years of age. We are currently examining mechanisms that may guide these two different patterns of eye growth in AccET.
Keywords: 722 strabismus •
547 hyperopia •
677 refractive error development