Age and racial variation in central corneal thickness of preschool and school-aged children

Purpose: The purpose of this study was to determine variations in central corneal thickness (CCT) of preschool and school-aged African American and white children. Secondary aims were to assess possible correlations between CCT measurements and gender, axial length, intraocular pressure (IOP), family history of glaucoma, or history of prematurity. Methods: Contact ultrasound was used to measure CCT and axial length in 76 white and 60 African American children between the ages of 7 months and 18 years. A questionnaire was completed by the parents or guardians, including medical and family history. Statistically significant associations and differences were assessed using the independent t test, analysis of variance, and linear regression. All associations were defined as significant when the alpha value was less than 0.05 (two-tailed). Results: Mean CCT was thinner in African American children (535 +/- 35 mu m) compared to white children (559 +/- 38 mu m) (P <.001). The corneal thickness in children ages 10 to 18 years was significantly higher than in all other age groups in both African American (P =.03) and white (P <.005) children. No association was found between CCT and gender, axial length, IOP, or family history of glaucoma. Premature children had thinner CCT (536 +/- 40 mu m) than full-term children (552 +/- 38 mu m) (P = .009). Conclusions: African American children have a thinner CCT compared to white children at all ages. Children of both racial groups have an increasing value of CCT with increasing age after approximately age 10 years. Children born prematurely have a thinner CCT than full-term children.