SEP 30, 2011
Data on central corneal thickness (CCT) among children is limited. The Pediatric Eye Disease Investigator Group sought to change that with this large prospective, multicenter study. They found that CCT increases modestly with age, with most of the change occurring before age 11. In addition, CCT was similar in white and Hispanic children but lower in African American children.
The study included 2,079 healthy white, African American and Hispanic children, ranging in age from birth to 17. CCT was measured with a handheld contact pachymeter.
African American children had thinner corneas on average than white and Hispanic children (P < 0.001 for both) by approximately 20 µm. Median CCT increased each successive year from age 1 to 11, with year-to-year differences steadily decreasing and reaching a plateau after age 11 at 573 µm in white and Hispanic children and 551 µm in African American children. For every 100 µm of thicker CCT measured, IOP was 1.5 mm Hg higher on average (P < .001). For every diopter of increased myopic refractive error, CCT was 1 µm thinner on average (P < 0.001).
Typically CCT is only measured in glaucoma suspects . This paper adds to the normative database, particularly in an age group that only has CCT measurements performed in the setting of possible or definite pathology. In my glaucoma practice, I often screen the relatives of my glaucoma patients. When I find a patient who has a normal clinical exam with no signs of glaucoma and the incidental finding of a thin CCT, I wonder about the risk of developing glaucoma and whether they should be monitored as a glaucoma suspect.