Abstract
Purpose :
Patients with dry eye disease experience greater tear film instability and more rapid rates of tear film break-up. This faster decay of ocular surface protection can impact visual function, as a smooth, regular tear film is critical to maintaining best corrected visual acuity (BCVA). Using an enhanced version of the inter-blink interval visual acuity decay (IVAD) test (1), we examined the impact of an artificial tear compound (Systane Ultra, Alcon, Inc.) on visual function between blinks.
Methods :
We tested 15 patients (12 female; mean age 62 yo) with a reported history of dry eye disease. To examine how visual acuity changed between blinks for these patients, we used an upgraded version of the IVAD test (1). In this test, patients are instructed to blink three times and then hold their eye open. While holding their eye open, patients identify rotated Landolt C images presented at their distance BCVA for each eye, with time to visual acuity decay determined by patients’ accuracy at this task at various time points between blinks. We repeated the test for each qualifying eye at 5 time points (prior to the administration of the artificial tear, and again at 5, 15, 45, and 90 minutes post-administration).
Results :
Our findings revealed that prior to the administration of the artificial tear, patients maintained BCVA for 12.3±2.3 seconds before experiencing decay. Soon after the drop was administered, time increased by more than 50% at both the +5-minute (18.8±3.3 seconds; p=0.0008) and +15-minute (22.1±2.5 seconds; p=0.0449) timepoints before returning to baseline (12.9±1.7 and 12.6±2.1 seconds at +45- and +90-minute time points respectively; both p > 0.85).
Conclusions :
Our new version of a technique to assess visual function in dry eye disease revealed that a commercially available artificial tear can help significantly prolong the duration of BCVA in patients with dry eye disease. This effect is transient across the time course, with a larger effect soon after the drop is administered (+5 and +15 minutes) and returning to baseline by the 45-minute time point. These results add further evidence demonstrating how tear film stability impacts visual function in patients with dry eye disease (1) and support the usefulness of the IVAD test as a novel end point for assessing visual function in new therapies developed for the treatment of dry eye disease.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.