Correlation of central corneal thickness and associated factors in premature infants with and without retinopathy of prematurity

Objective: Central corneal thickness (CCT) in premature infants is described in racially homogenous populations, and factors affecting CCT in infants are relatively unknown. This study describes CCT in premature infants and its association of steroid and oxygen requirements, gestational age (GA), birth weight (BW), race, and their relationship with CCT and corneal haze.

Methods: CCT measurements of 87 infants/174 eyes screened for retinopathy of prematurity were taken between 30 and 44 weeks of GA. CCT was analyzed using a mixed model for its relationship with BW, GA, race, corneal clarity, steroid, and oxygen use.

Results: Average CCT decreased at a rate of 12.3 μm/week. Caucasians had the thickest corneas and Hispanics the thinnest (p < 0.01) at baseline, but the rate of CCT decline varied based on racial/ethnic group (p = 0.079). Infants with BW <1000 g had a higher CCT at baseline, but CCT decreased at a faster rate than infants with higher BW (-13. 4 μm/week vs -9.9 μm/week, p = 0.020). Infants born <27 weeks of GA had higher CCT at baseline, but CCT decreased at faster rate compared with patients born later (-13.3 μm/week vs -10.1 μm/week, p = 0.029). Steroid and oxygen use were not statistically significantly associated with CCT or corneal haze (p > 0.05) CONCLUSIONS: CCT varies by racial group in premature infants. Lower BW and GA are associated with increased CCT at baseline but thin at a faster rate. Average, CCT decreases at a rate of 12.3 μm/week between 30 and 44 weeks GA and averages to 550 μm by 44 weeks GA.