Video Viewing Blink Rate in Normal and Dry Eyes

Decreased blink rate during video display viewing (VDV) has been reported; however, patients with tear dysfunction often complain of more frequent blinking. The objectives were to compare blink rates during conversation and VDV in normal and dry eyes and correlate blink rates with signs and symptoms.

Blink rate was measured with an infrared blink sensor for 2 minutes during conversation and for 2 minutes while watching a video clip (VDV) in patients without dry eye disease (control, n=18) and in patients with tear dysfunction from meibomian gland dysfunction (MGD, n=23), conjunctivochalasis (CCh, n=19), and aqueous tear deficiency (n=34; non-Sjögren syndrome n=18 and Sjögren syndrome n=16). Patients completed visual analogue questionnaires assessing irritation frequency and severity and blink frequency and underwent an ocular surface evaluation. Group comparisons and correlations were calculated.

Compared with control, conversational and VDV blink rates were significantly higher in CCh and aqueous tear deficiency (P≤0.005). Self-reported blink frequency was higher in all tear dysfunction groups compared with control. The VDV blink rate was significantly lower than the conversation blink rate in the control group (P=0.006) but not in any of the tear dysfunction groups. Conversational and VDV blink rates were significantly correlated with irritation frequency and severity.

Blink rate decreases during VDV in normal eyes; however, this blink rate suppression was not observed in patients with tear dysfunction, perhaps because of their irritation symptoms or tear instability.