Effect of orthokeratology lenses and frame lens on eye regulation parameters in myopic children

Abstract:

AIM:To study the effect of orthokeratology on accommodation function in myopic children.

METHODS: This was a retrospective clinical study. The clinical data of myopia children in our hospital from September 2015 to December 2018, who wore orthokeratology contact lens(Ortho-k)or single vision lens(SVL)to control myopia were analyzed. 27 cases(54 eyes)with Ortho-k were all selected as the study group, the control group was matched from 108 cases(216 eyes)of the SVL group with the Propensity Score-matching(PSM)function of SPSS software. After matching, 27 cases treated with Ortho-k were compared to 27 cases treated with SVL. Accommodation function were assessed by accommodative amplitude(AA), accommodative sensitivity(AS), accommodative lag(LAG), negative relative accommodation(NRA), and positive relative accommodation(PRA)before and 1, 3, 6 and 12mo after treatment.

RESULTS: There was no statistical significance in the differences of the accommodative parameters between groups(all P>0.05); Wearing time had a significant effect on AA, AS, LAG, NRA and PRA of myopic children in two groups(F_AA=4.7, F_AS=5.6, F_LAG=10.2,F_NRA=7.06, F_PRA=8.8, all P<0.05). Meanwhile, there was an significant interaction effect on the accommodative parameters between wearing time and wearing types of the two groups(F_AA=5.3, F_AS=4.6, F_LAG=11.4, F_NRA=3.4, F_PRA=11.1, all P<0.05).

CONCLUSION: Wearing orthokeratology can improve the accommodation function of myopic children, which may be one of the mechanisms by which they control myopia.