RESUMO
Objective To investigate the effects of the eye drops containing deproteinized calf blood extract on the ocular surface and tear film at the early stage of orthokeratology treatment in myopic adolescents.Methods Together 59 myopia (118eyes) who received vision correction by orthokeratology lens between June 2016 and October 2016 were included in this study,and they were randomly assigned into two groups:the treatment group,29 patients (58 eyes) receiving the eye drops containing deproteinized calf blood extract to presumably promote the repair of corneal epithelium,and the control group,30 patients (60 eyes) without receiving such eye drops.For each subject,the surface regularity index (SRI) and objective scattering index (OSI)were recorded;lipid layer thickness (LLT) and tear film break-up time (BUT) were measured,and finally fluorescein stain of corneal epithelium and the ocular surface disease index (OSDI) questionnaire were performed before treatment and 1 week and 1 month after lens wearing.Results The treatment group showed significantly lower rate of corneal staining than the control group at 1 week (10.3％ vs.33.3％,all P ＜0.05) and 1 month after treatment (8.6％ vs.26.7％,all P ＜ 0.05).There was no significant difference in LLT at 1 week and 1 month after treatment and before treatment (all P ＞ 0.05).Both corneal curvature and BUT were decreased,while SRI,OSI,and OSDI score were increased significantly after 1-week lens wearing (all P ＜ 0.05),but there was no significant difference at 1 week and 1 month after lens wearing (all P ＞ 0.05).Moreover,there was no significant difference in corneal curvature,SRI,BUT,LLT,OSI,and OSDI score at different time points between the treatment group and the control group (all P ＞ 0.05).Conclusion Eye drops containing deproteinized calf blood extract can protect and repair the corneal epithelium at the early stage of orthokeratology treatment.