Purpose: To study the corneal thickness of young emmetropic subjects.
Methods: One thousand eyes of 1000 young healthy emmetropic subjects were analyzed with the Orbscan Topography System II (Orbscan, Inc, Salt Lake City, UT) from January 2001 to May 2003. The age of the subjects ranged from 20 to 30 years old (mean +/- SD = 27.12 +/- 2.86). The mean of 5 consecutive measurements of the corneal thickness in the center of the cornea and at temporal, superotemporal, inferotemporal, nasal, inferonasal, and superonasal cornea were recorded.
Results: The corneal thickness at the following areas ranged as follows: 518 to 589 microm center; 603 to 678 microm nasal; 620 to 689 microm superonasal; 600 to 669 microm inferonasal; 571 to 639 microm temporal; 601 to 669 microm superotemporal; and 572 to 647 microm inferotemporal. In each individual the difference between the central thickness and the maximum paracentral thickness ranged from 85 to 107 microm (mean +/- SD, 99.21 +/- 3.80). The difference between the central thickness and the minimum paracentral thickness ranged from 36 to 59 microm (48.97 +/- 4.23 microm). The difference between the minimum paracentral corneal thickness and the maximum paracentral corneal thickness ranged from 37 to 58 microm (50.24 +/- 4.30). The tonometry was statistically correlated with the corneal thickness (P < 0.05 at each corneal location analyzed).
Conclusions: In emmetropic corneas the difference between the minimum paracentral thickness and the maximum paracentral thickness was similar to the difference between the central thickness and the minimum paracentral thickness.