AIM: To investigate the difference of ocular higher order aberrations between curvature myopia and axial myopia in moderate myopic eyes, according to the analysis of higher order aberrations in different types of moderate myopia.

METHODS: It was a prospective study. Totally 39 moderate myopic subjects(56 eyes, myopia with no astigmatism)participated in this study and were divided into two groups: group A was moderate curvature myopia group(11 patients,16 eyes),with average age 22±2 years, mean axial length of 23.89±0.13mm, mean corneal curvature 45.56±0.95D and mean diopter -4.58±0.82D. Group B was moderate axial myopia group(53 patients, 79 eyes), with average age 22±3 years, mean axial length of 25.82±0.44mm, mean corneal curvature 41.93±0.85D and mean diopter -4.50±0.78D. The values of higher order aberrations were analyzed at different pupil diameters between the two groups.

RESULTS: The comparison on mean age between the two groups had nosignificant difference as well as that on mean diopter(P>0.05). The comparisons on both average curvature of cornea and mean axial length showed significant differences(P<0.05), respectively. The values of RMS3, RMS4, RMS6, RMSh and C12 of the two groups(Group A/Group B)were 0.165±0.064/0.098±0.045, 0.127±0.034/0.059±0.025, 0.040±0.014/0.028±0.010, 0.218±0.059/0.129±0.040 and 0.137±0.057/0.048±0.037, respectively, when pupil diameter was 6mm and the comparison of the two groups had significant differences(P<0.05). Meanwhile the comparisons of ocular higher order aberrations on group A and group B also presented significant differences(P<0.05), with the former higher than the latter.

CONCLUSION: Curvature myopia had more coma, spherical aberration, secondary spherical aberration and total higher order aberrations than axial myopia in moderate myopic eyes in normal and moderately dilated pupils.