To compare the difference of the ocular surface and efficacy of orthokeratology lenses wearing after using sodium hyaluronate eye drops, rewetting drops and saline solution.

A randomized single-blind controlled trial was conducted.A total of 90 right eyes from 90 myopic patients were recruited from June 2017 to April 2018 in Hainan Eye Hospital.All the subjects received vision correction by orthokeratology lens, and were randomly divided into three groups by random number table method, with 30 eyes in each group.The sodium hyaluronate group was given preservative-free sodium hyaluronate eye drops (1 g/L), the rewetting drops group was given rewetting drops, and the saline solution group was given nonpreserved 0.9% NaCl.The vision, subjective refraction, corneal topography, non-invasive first tear film break-up time(NIKf-BUT) and fluorescein stain of corneal epithelium (FL) were detected before and 1 day, 1 week, 1 month, 3 months after the lens wearing.This study adhered to the Declaration of Helsinki and was approved by the institutional Ethical Committee Review Board of Hainan Eye Hospital.

The NIKf-BUT in the sodium hyaluronate group at 1 day, 1 week, 1 month and 3 months after wearing orthokeratology lens was (7.13±1.71), (6.61±1.49), (6.37±1.82) and (7.01±1.63) seconds, respectively, which was obviously higher than (6.32±1.71), (5.53±1.42), (5.57±1.50) and (6.17±1.63) seconds in the rewetting drops group at the corresponding time points and (6.36±1.58), (5.81±1.49), (5.74±1.77) and (6.28±1.53) seconds in the saline solution group at the corresponding time points (all at P<0.05). There was no statistically significant difference in FL score between the rewetting drops group and saline solution group at 1 day, 1 week, 1 month and 3 months after wearing the orthokeratology lens (all at P>0.05). Lower FL scores were observed in the sodium hyaluronate group compared to the the rewetting drops group and saline solution group after wearing the orthokeratology lens (all at P<0.05). No differences were found in uncorrected visual acuity, spherical equivalent and average K value among the groups (all at P>0.05).

Compared with the rewetting drops and saline solution, the preservative-free sodium hyaluronate eye drops can stabilize the tear film and have less effect on corneal epithelium at the early stage of orthokeratology lens wearing.However, there is no significant difference in the improvement of visual acuity and the rate of corneal shaping.

Myopia; Orthokeratology; Sodium hyaluronate; Eye drops; Break-up time of tear film; Fluorescein stain