Abstract
Purpose :
This study objectively evaluated the relationship between eye dryness and visual fatigue using the noninvasive tear film break-up time (NI-BUT) and binocular fusion maintenance (BFM).
Methods :
A total of 11 young healthy individuals (mean ± standard deviation, 20.7 ± 1.4 years old) participated in this study. The NI-BUT was measured using RT-7000, which evaluates the change in corneal refraction due to tear film instability. The BFM was assessed by measuring the transmittance of the liquid crystal shutters placed in front of the participant’s non-dominant eye when binocular fusion was broken, and vergence eye movement was induced. A questionnaire on the subjective symptoms experienced was administered to the participants before and after the visual task, wherein they were required to play a racing game using a smartphone for 30 minutes. The blinking during the digital device was measured using video-oculography with a sampling rate of 240 Hz.
Results :
NI-BUT was significantly shorter in the post-visual task (5.69 ± 3.11 s) than in the pre-visual task (9.12 ± 1.00 s) (P = 0.012). The BFM was significantly lower in the post-visual task (75.0% ± 16.2%) than in the pre-visual task (95.0% ± 9.29%) (P = 0.012). The change in NIBUT (post – pre) (−3.43 ± 3.19) was significantly and positively correlated with the change in BFM (−20.0% ± 17.8%) (R2 = 0.385, P = 0.042). The blink rate (11.8 ± 6.7 times) was significantly and negatively correlated with the NI-BUT (τ = −0.55, P = 0.019).
Conclusions :
These findings suggest that eye dryness is associated with visual fatigue during smartphone use.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.