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.
Significance: When using lissamine green for bulbar conjunctival evaluation, the most staining was observed with two applications of the same strip in the same eye, wetted with a drop of saline. The first application was 5 seconds after wetting the strip, and the second was 1 minute later, followed by immediate viewing. This suggests that bulbar staining should be viewed before the lid wiper region.
Purpose: This study aimed to optimize the assessment of lissamine green staining of the bulbar conjunctiva by investigating the application technique and subsequent observation period.
Methods: Twenty-two participants with dry eye (as defined by the Tear Film and Ocular Surface Society Dry Eye Workshop II) were recruited to trial five application methods in randomized order: (1) application immediately after wetting a single strip, (2) application 5 seconds after wetting a single strip, (3) application 10 seconds after wetting a single strip, (4) consecutive single application of sodium fluorescein followed by lissamine green 5 seconds after wetting, and (5) two applications using the same lissamine green strip 5 seconds after wetting, 1 minute apart. Slit-lamp photography of the conjunctiva was performed immediately following application and at 30, 60, 90, and 300 seconds after application. Three experienced (masked) practitioners independently quantified the visible punctate spots and graded the staining intensity within the images in a random order.
Results: Values for punctate spot count ( F = 6.29, p<0.0001) and lissamine green staining intensity ( F = 6.29, p<0.0001) varied significantly between the different application methods. Using two applications of the same lissamine green strip, 1 minute apart, in the same eye resulted in the greatest values for both punctate spot count and lissamine green staining intensity. Lissamine green staining decreased with time for both spot count ( F = 18.87, p<0.0001) and lissamine green staining intensity ( F = 11.33, p<0.0001), with the most staining found immediately after application followed by a gradual decline. There was no evidence of any interaction effect between time and application method for either measure (p>0.05 for both).
Conclusions: The optimal approach for assessing bulbar conjunctival lissamine green staining involves two applications of a whole infused drop resting on the same strip for 5 seconds, applied 1 minute apart. The ocular surface should be viewed immediately after application to maximize the conjunctival staining observed.