In recent decades, the significant increase in digital screen use, both at home and at work, has been accompanied by a growing prevalence of dry eye disease worldwide. The high visual and cognitive load associated with digital screen use, along with sustained visual attention, can result in a reduction of blinking frequency by a factor of two or three times. Reduced blinking frequency or quality can compromise the delivery and distribution of tear film components over the ocular surface, leading to tear film destabilisation and breakup, and the consequent development of dry eye symptoms.

Furthermore, low humidity environments are common in the modern workplace with the widespread use of air conditioning and central heating. These are recognised to exacerbate dry eye severity through creating a larger water vapour pressure gradient between the ocular surface and external environment, increasing the rate of aqueous tear evaporation.

The efficacy of a USB-powered desktop humidifier to provide dry eye relief was examined in a recently published, masked, randomised, crossover trial conducted by the University of Auckland Ocular Surface Laboratory (OSL). A total of 44 participants were recruited and randomised, on separate days, to a one-hour period of continuous computer use, with and without exposure to the desktop humidifier. Tear film parameters and ocular comfort were assessed before and after computer use.

The results of the study showed that while the desktop humidifier effected only a modest increase in relative humidity locally, a significant increase in tear film stability was observed, which was associated with a higher proportion of participants reporting greater subjective ocular comfort.

References

Wang MT, Chan E, Ea L, Kam C, Lu Y, Misra SL, Craig JP. Randomized Trial of a Desktop Humidifier for Dry Eye Relief in Computer Users. Optometry & Vision Science. 2017;94(11):1052-1057.

By Dr Michael Wang, Evon Chan, Linda Ea, Clifford Kam, Yvonne Lu, Dr Stuti Misra and A/Prof Jennifer Craig