Abstract
Purpose :
Patients with dry eye disease experience greater tear film instability and more rapid rates of tear film break-up, especially when exposed to adverse conditions. In this study we looked at how patients reacted via blinks and decreased interpalpebral fissure height (i.e. squinting) as we increased the rate of airflow hitting their eye within an FDA approved model of dry eye disease (DED) provocative test, the Ora’s Controlled Adverse Environment (CAE).
Methods :
We tested 8 patients (6 female; mean age 71 yo) with a reported history of DED and a tear film break up time less than 5 seconds. Videos were recorded over a 15 minute period of increasing airflow every 2 minutes starting at 1 minute. Blink rate was measured over one-minute intervals at 3 time points while patients had undergone sequentially increasing airflow. Interpalpebral fissure height was measured as the distance between the upper and lower eyelid over 2 frames within the same minute that blink rate was captured.
Results :
All subjects experienced an increase in blink rate, which e increased by 36% on average with each airflow increase. Interpalpebral fissure height was relatively unchanged at the first airflow increase, but then decreased in size by an average of 28% (minimum of 7% maximum of 40%) at maximum permissible airflow.
Conclusions :
Video acquisition during increased airflow revealed an increase in the blink rate and a decrease in the interpalpebral fissure height. Interpalpebral fissure height decreased more at higher airflows indicating that there is a precise airflow for each subject where their eyes remain the most susceptible to exposure. These findings have implications for determining new endpoints for clinical trials in DED.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.