Effect of a light-emitting timer device on the blink rate of non-dry eye individuals and dry eye patients

Purpose To evaluate blink rate effects by a novel light-emitting diode (LED) timer device (PISC) on non-dry eye (DE) subjects and DE patients during a reading task on liquid crystal display (LCD) screens, in different environmental conditions. Methods This was a case–control study that included 15 DE patients and 15 non-DE subjects as controls. Participants had their blink rates measured while they read an electronic format text. These tasks were performed in four different conditions: with and without a LED timer device in two visits, and with and without air conditioning. All participants completed the Ocular Surface Disease Index and were examined by best spectacle-corrected visual acuity exam, biomicroscopy, Schirmer test 1, fluorescein staining and break-up time and lissamine green staining (Oxford scale grading). Results Outcomes between reading tasks conditions were compared independently for each group and blink rate frequency was higher in tasks with LED timer device, with and without air conditioning, for the DE group (p<0.0001), and with air conditioning for the control group (p<0.05). Conclusions An LED timer device increased blink frequency for DE and control groups. Further studies need to be carried out in order to evaluate long-term effects of this new device, as well as its assessment with different reading scenarios.