SUMMARY
Accuracy and reproducibility of the EyeSys videokeratography system was evaluated on a plastic sphere (42.50 D) and on 58 corneas of 58 patients, divided into four groups: 30 normal corneas, 10 post radial keratotomy corneas, 8 post excimer laser corneas and 10 keratoconic corneas. A method including all measurement points in the accuracy and reproducibility analysis was used. The EyeSys system showed on the plastic sphere an accuracy of 95% of the measurements within 0.25 D and higher reproducibility levels on the central (mean 0.0295 D) than on the peripheral (mean 0. 0962 D) region. The normal, post radial keratotomy and post excimer laser corneas showed similar reproducibility levels on the central (means 0.1524 D, 0.1406 D, and 0,0962 D, respectively) and peripheral (means 0.4484 D, 0.4673 D and 0.3138 D, respectively) regions. In the Keratoconus reproducibility was lower than in the other groups (p < 0.05), both on the central (mean 0.3808 D) and peripheral (mean 0.8458 D) regions. In the four groups, reproducibility was significantly higher on the central cornea (p < 0.05). The EyeSys system seems to be able to provide useful clinical information about the corneal surface, particularly over its central region.