AIM: To evaluate anterior segment changes during accommodation in different degree of myopia with OCT.

METHODS: Sixty myopes with the age from 18 to 39 years were enrolled in this study and were divided into two groups: low to moderate myopia group(>-6.0D), and high myopia group(≤-6.0D). Anterior segment measurements were performed by anterior segment optic coherence tomography(OCT)under three different accommodative state of relax(0.0 D), 3.00D and 5.00D. The posterior corneal curvature(PCC), anterior chamber depth(ACD), lens thickness(LT), pupil diameter(PD)were compared at different accommodative state using repeated measures ANOVA.

RESULTS:Low to moderate myopia group comprised 32 myopes with the mean age 29.34±4.65 years, mean spherical equivalent -3.72±1.05D; High myopia group comprised 28 myopes with the mean age 29.57±5.89 years, mean spherical equivalent -7.05±0.85D; With the accommodation relaxed(0D), there was no difference between the low to moderate myopia group and high myopia group both in PCC and LT, ACD was 2.92±0.23mm in high myoia and 2.67±0.19mm in low to moderate myopia(t=-4.637, P=0.000). Pupil diameter was 6.21±0.56mm in low to moderate myopia and 5.95±0.42mm in high myopia(t=2.011, P=0.049). With the accommodation increased, ACD decreased significantly, LT increased significantly, and PD decreased significantly in both groups(all P<0.05). The PCC has no significant change during accommodation in both groups(all P>0.05).

CONCLUSION: Anterior segment OCT can find the alteration of ACD, LT and PD with accommodation. During accommodation, the cornea is stable. However, with the accommodation increased, ACD, greater changes happened in LT and PD using anterior segment OCT.