Comparison of keratometric readings as obtained by Javal Ophthalmometer and Corneal Analysis System (EyeSys)

We examined 92 normal eyes using Javal Ophthalmometer and Corneal Analysis System (EyeSys) intending to compare the keratometric readings obtained by these two instruments. Dioptric power and location at flatter and steeper meridians, keratometric astigmatism values, and average central keratometric power were measured in the central cornea of all eyes. Statistical analysis showed significant differences in flatter meridians' mean power values (mean difference = 0.13 D, P = .008), mean keratometric astigmatism values (mean difference = -0.20 D, P = .001) and steeper meridians' location (mean difference = 7 degrees, P = .0001). There was no significant difference in steeper meridians' mean power values (mean difference = -0.06 D, P = .38), flatter meridian location (mean difference = 5.9 degrees, P = .07), and mean average central keratometric power (mean difference = 0.03 D, P = .471). Clinically meaningful difference was observed only in keratometric astigmatism readings of eyes with keratometric astigmatism higher than 1.50 D (mean difference = -0.84 D). For all the other parameters measured, the differences between the two instruments readings were clinically acceptable.