Changes in corneal epithelial irregularity following treatment with artificial tears.

Significance: Dry eye sufferers have a highly irregular corneal epithelial surface compared with those without dry eye. This study demonstrated that corneal epithelial thickness irregularity can be significantly reduced after as little as 48 hours following treatment with regular use of topical ocular lubricants.

Purpose: This study aimed to compare changes in corneal epithelial thickness irregularity factor (EIF) and ocular symptoms in a population with symptoms of dry eye before and up to 4 weeks after treatment with two commercially available lubricating eye drops versus saline.

Methods: We conducted a prospective single-center, investigator-masked, randomized, parallel-group dispensing study. Participants with moderate to severe symptoms of dry eye (Ocular Surface Disease Index score >23 at baseline) were enrolled and randomly assigned to receive either 0.15% hyaluronic acid + hydroxypropyl guar, 0.2% hyaluronic acid, or saline (16 in each group). Corneal epithelial thickness measurements were obtained along vertical and horizontal CASIA SS-1000 Optical Coherence Tomography scans at baseline and after 48 hours, 2 weeks, and 4 weeks. The Ocular Surface Disease Index questionnaire was administered at baseline, 2 weeks, and 4 weeks.

Results: Forty-eight participants (male-to-female ratio, 17:31) completed the study. Horizontal EIF was significantly lower at all follow-up visits compared with baseline (p=0.001), but there were no significant differences between study eye drops (p=0.34). No significant difference in vertical EIF was observed over time (p=0.32) or between eye drops (p=0.08). Ocular symptoms significantly improved after 2 and 4 weeks of treatment compared with baseline (p<0.001), but no differences were observed between eye drops (p=0.46).

Conclusions: All treatments were effective for reducing EIF along the horizontal meridian 48 hours after initiation of treatment, and improvements were maintained for 4 weeks. Improvements in ocular symptoms were observed with all study treatments.