Measurement and analysis of central corneal thickness in full-term newborns

Abstract

Objective To measure central corneal thickness (CCT) in full-term newborns, and to study the association with gestational age, birth weight, delivery mode, and gender. Methods This was a cross-sectional study. A subset of 221 full-term neonates (442 eyes) was included. The age of the neonates ranged from 1 to 3 days. There were 111 male neonates and 110 female neonates. CCT was measured quantitatively by a hand-held corneal pachymeter. Associations with neonatal factors were also studied. These included gender, gestational age, birth weight, and delivery mode. Data were analyzed using a t test, one-way ANOVA, Pearson correlation and multivariable linear regression analysis. Results No significant difference in CCT was found between right eyes (580 ± 51 μm) and left eyes (583 ± 53 μm). The mean value of the left and right eye CCT was defined as the neonatal CCT. Mean longitudinal CCT was 582 ± 50 μm, 95% CI was 575-588 μm. The neonatal CCT of male and femal were 591 ± 50 μm and 572 ± 48 μm, respectively. This difference was statistically significant (t=2.927, P 0.05) was found. Multiple linear regression analysis showed the regression equation: CCT (μm)=980.52-10.42 × gestational age(week)+ 18.60 × gender. Conclusion The full-term newborn CCT was 575-588 μm (95% CI). There was no significant difference in CCT between the right and left eyes. CCT values were higher in male neonates than females, and were negatively correlated with gestational age. However, there was no significant correlation between birth weight and CCT. Key words: Infant, newborn; Gestational age; Full-term delivery; Corneal thickness