Investigating the influence of the integrity and different decentration of orthokeratology defocus ring on axial length
Objective To retrospectively investigate the influence of the integrity and different decentration of or-thokeratology defocus ring on axial length(AL).Methods A prospective case-control study.210 eyes of 110 adolescents aged 8 to 18 years who with wearing overnight orthokeratology(OK)lens in the First Affiliated Hospital of Guangxi Univer-sity of traditional Chinese medicine were included.According to the integrity of the defocus ring,it was divided into the com-plete group and the incomplete defocus ring group.And the difference of baseline parameters(age,sex,eye difference,re-fraction)and 1-year AL growth was compared.According to the different levels of bias direction,the group was divided into temporal group,nasal group and middle group,and the three groups of baseline parameters and the difference of 1-year AL growth were compared.According to different vertical bias directions,they were divided into lower group,upper group and middle group.The baseline parameters of the three groups and the difference of 1-year AL growth were compared.Results(1)In the 210 eyes,187 eyes had complete defocus ring,and the 1-year AL growth was(0.21±0.23)mm.23 eyes had in-complete defocus ring,with an increase of(0.21±0.19)mm,and the difference of them and baseline parameter were not statistically significant(all P>0.05).(2)The correlation analysis between the overall deviation and the increase of ocular axis showed that(r=-0.16 P<0.05),there was a negative correlation,but the correlation was low.(3)Horizontal orienta-tion:temporal group(155 eyes),nasal group(10 eyes),and middle group(22 eyes).And there was no significant differ-ence in 1-year AL growth and baseline parameters in three different horizontal deviation directions(all P>0.05).(4)Com-pared with the growth 1-year AL in three different vertical directions,the growth of AL in thesuperior decentration(27 eyes)was higher than that in the inferior(93 eyes)and center position(67 eyes)(all P<0.05).There was no statistically signifi-cant between inferior deviation group and center group(P>0.05).Conclusions During the shaping process,the defocus ring may be incomplete,and the slight horizontal deviation has little effect on the myopia prevention and control effect of OK lens.In the vertical direction,the superior deviation should be avoided as far as possible to better prevent and control myopia.
OrthokeratologyDefocus ringDifferent decentrationAxial lengthMyopia prevention and control
国家科技期刊平台
NSTL
万方数据
维普
