Central corneal thickness and corneal diameter in premature infants.

BACKGROUND

Central corneal thickness is significantly greater in full-term infants than in adults. Very little is known about corneal thickness in premature infants.

METHODS

Measurements of central corneal thickness and horizontal corneal diameter were carried out in 35 premature babies (70 eyes) undergoing screening for retinopathy of prematurity. Initial measurements were taken at approximately 31 weeks gestational age and at intervals until term was reached.

RESULTS

Babies born at approximately 31 weeks have very thick corneas which show a progressive and statistically significant decrease to term. Conversely, horizontal corneal diameter shows a progressive significant increase to term. A very strong inverse correlation was found between these two parameters.

CONCLUSION

We demonstrate that premature infants have thick corneas and small corneal diameters. Central corneal thickness decreases dramatically from approximately 31 weeks to term and is mirrored by a significant increase in corneal diameter.