Normal Values for Central and Paracentral Corneal Thickness in the Pediatric Population

Abstract

Abstract: : Purpose: To determine normal central and paracentral corneal thickness measurements in the pediatric population and to determine if these measurements are consistent across different pediatric age groups and different ethnic groups. Methods: Pachymetry measurements were performed on 198 eyes of 108 patients undergoing routine ophthalmologic surgery under general anesthesia. The measurements were taken centrally and at four standard paracentral sites 3 mm from the corneal center. The two-tailed t test was used for comparison of the continuous means for values of corneal thickness. Analysis of variance (ANOVA) was performed to determine differences among age and ethnic groups. Results: The mean central corneal thickness (CCT) was 544 (± 46 µm). Paracentral corneal thickness mean values were as follows: superior, 575(± 52) µm; nasal, 568 (± 50 µm); inferior, 568 (± 51 µm); and temporal, 574 (± 47) µm. The mean CCT values were significantly thinner than at each of the mean paracentral points (p < 0.05 for each comparison, paired t-test). Paracentral corneal thickness measurements demonstrated no significant differences between locations (p > 0.05, variance analysis). The mean CCT ± SD for each age group was as follows: 6-23 months, 538 ± 40 µm; 2-4 years, 546 ± 41 µm; 5-9 years, 566 ± 48 µm; and 10-18 years, 554 ± 35 µm.( ANOVA p= 0.012).Analysis of variance (ANOVA) performed on central pachymetry values demonstrated no significant differences among racial subgroups. Conclusions: Pediatric central and paracentral corneal thickness are consistent with those of adults.

Keywords: cornea: clinical science • shape and contour