AIM: To investigate the related factors influencing the myopia control effect in adolescents with orthokeratology.

METHODS: This study selected 102 adolescents who wearing ortho-k lens in the First Affiliation Hospital of Xi'an Jiaotong University during July 2014-October 2017.Their axial elongation, refraction, wearing time were observed.

RESULTS: After 3a treatment, the axial elongation of 102 adolescents increased 0.42±0.37mm. Among the low myopia, the middle and high myopia groups, the axial elongation increased 0.65±0.35mm, 0.32±0.37mm and 0.30±0.29mm, respectively. The axial elongation in the high myopia groups was the most slowest(the combination of orthokeratology and spectacles); There was an interaction between the wearing time and the initial refraction, the wearing time and the initial age(all P<0.001). It is suggested that the axial elongation is slower in middle-high myopia than that in the low myopia. The axial elongation was slower in the older adolescents than that in the younger adolescents; There was no interaction between wearing time and gender(F=0.292, P=0.695). The axial elongation has no difference between male and female.

CONCLUSION: The initial refraction and the initial age of myopic adolescents were important factors influencing axial elongation. The combination of orthokeratology and spectacles has effection in controlling axial elongation.