A Study On The Profile And Factors Of The Higher Order In Myopia

Objective:To analyze the distribution of the higher-order aberrations in the population of China with myopia and astigmatism,and to determine whether the pupil size,degree of myopia and astigmatism offeet higher-order aberrations. Methods:103myopic astigmatism eyes were evaluated before refractive surgery by using a Hartmann-Shack method.The root mean square(RMS)values of higher-order aberrations for each subject with pupil diameters of5.0mm and6.0mm were calculated.The subjects were divided into following groups,high myopia(>-6.00D),medium myopia(-3.00～-6.00D)and low myopia(≤-3.00D),high astigmatism(≥0.75D)and low astigmatism(<0.75D).Results:Higher-order aberrations were increased significantly with increasing pupil size.The RMS values were decreased from3rd to5th order aberrations with pupil diameters of6.0mm in the same eye.The indi-vidual difference was63times in the same type of aberration.Spherical aberration and coma aberration were affected by high myopia;low and moderatc myopia did not effect higher order aberrations.Astigmatism only affected the coma aberra-tion, but not spherical aberration.Conclusion:The aberrations increase with the pupil diameters,the increasing of refractive error such as myopia and astigmatism.