gms | German Medical Science

The corneal thickness is an important parameter for exact measurements of IOP and for operations of the cornea such as LASIK or LASEK and corneal transplantations. Purpose of this study was to evaluate norm values for the Pentacam system and to compare them with values of other methods.

The central corneal thickness as well as the peripheral corneal thickness in 0°, 90°, 180° and 270°position in the 3-mm-zone were determined with the Pentacam system. The Pentacam system is based on a 180° rotating Scheimpflug camera, which is able to perform up to 50 measurements of anterior segments within about two seconds. 89 right eyes and 88 left eyes of 89 normal subjects were examined. Differences between sides and differences in gender as well as correlations between and age, body size and central corneal thickness were analyzed statistically in parametric tests.

The average central corneal thickness in all eyes was 607 ± 35 μm. The lowest corneal thickness in all eyes was found temporally and in the lower segment. The largest corneal thickness in all eyes was in the upper segment and nasally. The mean central corneal thickness in females was 605 ± 38 μm, in males it was 607 ± 33 μm. Differences in gender proved to be not significant in t-test for independent samples (p=0,71). There were no significant differences between right and left eyes in t-test for dependent samples (p=0,08). Statistically there was no proof of correlations between age, body size and central corneal thickness.

Non-contact measurements of central and peripheral corneal thickness can be performed with the Pentacam system. The central measurements though differ from other pachymetric methods. The gathered norm values are useful to interpret future pachymetries with the Pentacam system specifically.