ABSTRACT
Objective This study was to observe the meibomian gland scores,the miss rate of meibomian,break-up time of tear film (BUT) changes after long-term wearing orthokeratolog,and to evaluate orthokeratolog impact on meibomian gland function and the stability of the tear film.Methods A prospective case-controlled study was performed.Fifty patients 98 eyes with myopia were enrolled.According to the myopia correction mode,the patients were divided into control group (24 cases) and experimental group (overnight orthokeratolog treatment) group (26 cases).All subjects were underwent the examinations sequentially as follows:evaluation of ocular surface disease symptoms using the Ocular Surface Disease Index (OSDI),lid margin and ocular surface examination by slit lamp microscrope,infrared meibomian photography and BUT.All measurements were repeated at 3 months,6 months,24-months follow-up visit.All patients signed informed consent before examination.Results After wearing orthok-contact lens for 24 months,the meibomian gland score was 4.54±1.10 and 2.29±0.75 in the experimental group and control group,respectively,the difference was statistically significant (P＜0.05).The BUT was (6.35 ± 1.52) s 24 months after wearing orthokeratolog,which was less than (9.38 ± 1.88) s in the control group,the difference was statistically significant (P＜ 0.05).The miss rate of meibomian gland was 24.39 ± 5.54 and 22.81 ± 5.23 in the experimental group and control group,respectively.There was no statistically significant difference among the the miss rate of meibomian gland between groups and within groups (all at P＞0.05).Conclusions Long-term wearing orthokeratolog has negetive effects on meibomian gland function and the stability of the tear film.