Central corneal thickness may increase with age up to 11 years

Arch Ophthalmol. 2011;129(9):1132-1138

Issue: December 25, 2011

Central corneal thickness in children increased with age and varied among racial subgroups, a large study showed.

"There is a minimal increase in measured IOP with increasing corneal thickness among children with no abnormalities," the study authors said. "There is no clinically important association between CCT and refractive error."

Investigators set out to determine central corneal thickness; variance in CCT by age, race or ethnicity; the age at which childhood CCT stabilizes; and associations between CCT and other clinical characteristics such as refractive error and IOP.

The prospective study included 2,079 healthy children ranging in age from newborn to 17 years who underwent CCT measurement with a handheld contact pachymeter. The study group included 807 whites, 494 Hispanics and 474 African Americans, in addition to subjects of Asian, mixed or unknown race.

Study results showed that African American subjects' corneas were about 20 µm thinner on average than those of white and Hispanic children; the differences were statistically significant (both P < .001). The difference between white and Hispanic subjects' CCT was not statistically significant.

East Asian subjects' corneas were 10 µm thinner on average than those of white subjects (P = .03), and 14 µm thicker than those of African American subjects (P = .001).

CCT increased from 1 year to 11 years. However, year-to-year differences steadily diminished and reached a plateau after 11 years. IOP increased an average of 1.5 mm Hg for each 100 µm of increased CCT, the authors said.

The Pediatric Eye Investigator Group has again addressed a topic that has been in question by many pediatric ophthalmologists with an excellent study on central corneal thickness in children. There is an increase in CCT from age 1 year to 11 years, in particular at the youngest ages, with African Americans having slightly thicker corneas than Hispanics and whites. The take-home message is that when the CCT falls between the 5th and the 95th percentile, there might be a variation of IOP of at most 2 mm Hg and this should not influence the presence or absence of glaucoma. It is also concluded that there is a minimal increase in IOP with increasing CCT among normal children and that the CCT has no effect on refractive error. The authors should be commended for this study clarifying questions that come up in our practices when we see patients to rule out glaucoma in young children.

– Robert S. Gold, MD
OSN Pediatrics/Strabismus Section Editor
Disclosure: No products or companies are mentioned that would require financial disclosure.