Abstract
Purpose :
We compared spontaneous blink rates during conversation with those during video display (VD) viewing in control and tear dysfunction (TD) patients and correlated their blink rates with symptoms of irritation and blink frequency.
Methods :
Spontaneous blink rate while passively listening to a description of their examination (spontaneous) and while watching a video clip (VD) was measured for 2 minutes with an infrared blink sensor in patients with no signs or symptoms of dry eye (control, n=18) and in patients with TD associated with Meibomian gland dysfunction (MGD, n=23), conjunctival chalasis (CCh, n=19), and aqueous tear deficiency: non-Sjogren syndrome (non-SS ATD,n=17) and Sjogren syndrome (SS ATD,n=18). Patients completed visual analogue scales assessing irritation and blinking frequency and a complete ocular surface evaluation was performed. T-test or ANOVA with post-hoc analysis and Pearson correlations were calculated between groups.
Results :
Compared to control (mean=18.6), spontaneous blink rate was higher in CCh (mean=58.4, P=0.005) and non-SS ATD (mean=47.9, P=0.02) and it was higher during VD viewing in the CCh group. Blink rate during VD viewing was significantly lower compared to spontaneous in the control (p=0.006) and non-SS ATD (p=0.02) groups, but there was no difference in the CCh, MGD and SS ATD groups. All four TD groups reported higher blink frequency symptoms vs. control. Significant correlations were found between spontaneous and VD blink rates (r=0.83, p<0.001), spontaneous blink rate and TBUT (r=-0.2, p=0.05) , irritation severity (r=0.36, p<0.0002) and frequency (r=0.31, p=0.001) and blink frequency (r=0.25, p=0.02). VD blink rate was correlated with irritation severity (r-0.36, p<0.0002) and frequency (r=0.31, p=0.02).
Conclusions :
As previously reported, blink rate decreases during VD viewing in the normal population; however there is no change in blink rate in patients with TD due to CCh, MGD and SS. Spontaneous and VD blink rates were significantly correlated with patient reported irritation severity and frequency, suggesting that eye irritation symptoms override the normal suppression of blinking during VD viewing. Patients with TD seem aware of their increased blinking because increased blinking was more frequently. The difference between spontaneous and VD blink rates may be useful to identify patients with tear dysfunction and to monitor treatment efficacy.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.