The contribution of intraocular lens calculation accuracy to the refractive error predicted at 10 years in the Infant Aphakia Treatment Study

PURPOSE To determine the relative contribution of intraocular lens (IOL) calculation accuracy and ocular growth variability to the long-term refractive error predicted following pediatric cataract surgery. METHODS Pseudophakic eyes of children enrolled in the Infant Aphakia Treatment Study (IATS) were included in this study. Initial absolute prediction error (APE) and 10-year APE were calculated using the initial biometry, IOL parameters, postoperative refractions, and mean rate of refractive growth. The cohort was divided into children with a low-initial APE (<= 1.0 D) and a high-initial APE (>1.0 D). The 10-year APE was compared between the two groups using the Mann-Whitney U test. Linear regression was used to estimate the variability in prediction error explained by the initial IOL calculation accuracy. RESULTS Forty-two children with IOL placement in infancy were included. Seventeen eyes had a low initial APE, and 25 eyes had a high initial APE. There was no significant difference in APE 10 years following surgery between individuals with a low initial APE (median, 2.67 D; IQR, 1.61-4.12 D) and a high initial APE (median, 3.45 D; IQR, 1.64-5.10 D) (P = 0.7). Initial prediction error could explain 12% of the variability in the prediction error 10 years following surgery. CONCLUSIONS IOL calculation accuracy contributed minimally to the refractive error predicted 10 years after cataract surgery in the setting of high variability in the rate of refractive growth.