AIM: To assess the effect of overnight orthokeratology on tear film and cornea biological characteristics in adolescents.

METHODS: Thirty-five myopia patients(70 eyes)worn overnight orthokeratology and fifteen myopia patients(30 eyes)worn frame glasses were involved in our study with complete follow-up information. We measured average tear breakup time(aBUT), basal tear secretion, corneal thickness and corneal curvature and corneal endothelium, then analyzed the differences in tear film stability and corneal biological characteristics between myopia patients of the both groups.

RESULTS: Compared with the frame glasses group, there was no significant difference in the difference of aBUT, basal tear secretion difference and corneal thickness between before and after wearing overnight orthokeratology(P=0.0922、0.0891、0.4181); there was significant difference in the difference of corneal curvature, corneal thickness, the coefficient of variation of corneal endothelial cell, and the percentage of corneal hexagonal endothelial cells between before and after wearing overnight orthokeratology(P=0.0000、0.0005、0.0002). No serious complications occurred in ocular surface in all follow-up cases.

CONCLUSION: Long-term overnight orthokeratology had no significant effect on tear film stability, but would increase the coefficient of variation of the corneal endothelial cell and reduce the percentage of corneal hexagonal endothelial cells. In order to diminish implications and guarantee the safety of orthokeratology, it should be closely observed, regular care.