Comparison of corneal curvature by different methods in myopic eyes

Objective To analyze the difference of keratometric readings obtained from auto keratometer,TMS corneal topography system and IOLMaster in myopic patients.Methods The corneal curvatures were measured with auto keratometer,TMS corneal topography system and IOLMaster respectively in 157(314 eyes)patients in our hospital from August 2010 to November 2010.There were 113 male(226 eyes)and 44 female(88 eyes).The differences of corneal curvatures were compared between male and female.Results The average keratometric readings with auto keratometer,TMS corneal topography system and IOLMaster were(42.40±1.43)D,(43.41±1.46)D,(43.27±1.44)D in males and(43.22±1.32)D,(44.29±1.30)D,(44.23±1.34)D in females respectively.There were statistical differences between male and female in corneal curvature(all P0.05).The corneal curvature was higher in female than in male.The average keratometric readings obtained from auto keratometer,TMS corneal topography and IOLMaster were(42.65±1.45)D,(43.65±1.44)D and(43.55±1.45)D,respectively.TMS corneal topography and IOLMaster had the similar measurements,but no difference was found(P0.05).The measurement of corneal curvature obtained from auto keratometer was lower 1.0 D than that from TMS corneal topography and 0.9 D than IOLMaster(both P0.05).There were statistical differences for auto keratometer compared with the other two methods(both P0.05).Conclusions The measurements of corneal curvature show different variation with auto keratometer,TMS corneal topography and IOLMaster.The corneal curvature is higher in female than in male.IOLMaster is a clinically useful tool in evaluating corneal curvature.