Age-based estimation of contact lens base curve in Filipino infants

ABSTRACT

@#<p style="text-align: justify;"><strong>Objective.</strong> To create an age-based formula to estimate the base curve needed for contact lens fitting using measured central corneal curvature (CCC) with a handheld auto keratometer from ophthalmologically normal infants.</p><p style="text-align: justify;"><strong>Methods.</strong> This is a prospective cross-sectional study involving 70 ophthalmologically normal full-term infants aged 0 to 12 months. The infants were divided into four groups: 0-3 months, >3-6 months, >6-9 months and >9-12 months. CCC was measured with a handheld auto keratometer and was used to compute for the base curve. Differences in CCC between the four groups were measured and linear regression models were used for formula creation.</p><p style="text-align: justify;"><strong>Results.</strong> The mean CCC was highest in group 1 at 45.5 ±2.4 diopters (D). These values slowly decreased as age increased. A formula predictive of the base curve based on the infants age was derived using linear regression analysis. It predicted that for every month increase in age, there is a 0.063 millimeter increase in the base curve (p<0.001).</p><p style="text-align: justify;"><strong>Conclusion.</strong> Infant CCC is highest at birth and gradually decreases as age increases. The formula can predict the base curve needed for contact lens fitting in infants without the need for a handheld autokeratometer.</p>