Assessment of effect of artificial tears on Tear Meniscus Height and Non-invasive Keratographic Break-Up Time measures in rabbits

Abstract

Purpose : Artificial tear supplements (AT) are the most common therapy used to treat Dry Eye Disease (DED). Although numerous over-the-counter AT are available, objective, comparative data regarding their performance remains scant. We compare effects of 14 commercially available AT including perfluorohexyloctane (Miebo) on Tear Meniscus Height (TMH) and Non-invasive Keratographic Break-Up Time (NIKBUT) in rabbits (similar work in humans submitted as another poster). The data shed light on the relative performance of these agents and provides insight into DED pathophysiology.

Methods : All studies were in compliance with Stony Brook’s IACUC and ARVO’s policy on animal research. Refresh Optive, Refresh Relieva, Up&Up, Systane Ultra, Visine, Systane Complete, Retaine MGD, Soothe XP, Genteal Tears, Bio-True, Hylo-Tears, Ivizia, Similasan, Miebo, and Saline were tested on 8 eyes of 6 New Zealand White rabbits. After minor modifications to the advanced keratography unit’s platform (OCULUS Keratograph 5M), TMH and NIKBUT were measured as per manufacturer instructions. 8 measures were recorded for each AT at baseline, 5- and 15 minutes (min) post drop application. Statistical analysis (ANOVA / t tests) was done with XLstat.

Results : 5/14 AT had a statistical increase in TMH at 5 min (9/14 non-statistical increase). The effect diminished by 15 min (Figure 1). Only 1 drop (Systane Complete) showed statistical increase in TMH at both 5 and 15 min. ANOVA showed that Soothe XP was better than Similasan; and that Hylotear was better than Similasan. All other product comparisons were equivalent. No significant increases in NIKBUT at 5 or 15 min were seen.

Conclusions : Effects of AT on TMH in rabbits are short lived (usually under 15 min). Various AT differentially improve TMH but the performance of most are statistically equal.

No AT significantly increased NIKBUT from baseline at any time point. Many AT decreased NIKBUT possibly due to non-uniform mixing of the AT and natural tearfilm or variability inherent in NIKBUT measures.

A more complex interaction between AT and the ocular surface may explain why some NIKBUT increased at 15 minutes but not at 5 minutes for some AT.

Assessment of the effects of AT on these parameters can provide insight into the pathophysiology and treatment of DED.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.