How Does Digital Eye Strain Contribute to Dry Eye Syndrome?
During the COVID-19 pandemic, there was a rise in cases of dry eye syndrome in places where stay-at-home orders were mandated. This phenomenon led researchers to pinpoint the link between dry eye syndrome and prolonged screen use.
Blue Light Exposure
Blue light is emitted by the sun, indoor lighting and digital devices with screens.
While the amount of energy blue light these devices emit is only a fraction of that in sunlight, many eye doctors are increasingly concerned by the amount of time people spend using these devices and the proximity of these screens to the user’s face.
A 2019 study involving primary human corneal cells in the BMJ Open Ophthalmology found that certain levels of blue light damaged the cells on the eye’s surface, potentially contributing to dry eye syndrome.
However, more research is needed to determine whether the amount of blue light used in studies can harm a person’s eyes.
Another study published in the PLOS One (2016) journal concluded that wearing blue light blocking glasses improved the visual impairment caused by tear instability in patients with dry eye syndrome.
Infrequent Blinking
Another reason screen use can lead to dry eyes is insufficient blinking. People tend to blink less when focusing on text or images on a digital screen, with the blink rate dropping by 66% when using a computer.
Blinking helps keep our eyes healthy and comfortable. With every blink, the ocular surface is cleaned of debris and lubricated, so less blinking means more irritation and dryness.
In 2018, researchers from the Northern Clinics of Istanbul conducted a small-scale study involving 30 people who spent 8 hours on the computer per day, and 30 people who spent 1 hour on the computer per day. They found that the prolonged use of a computer significantly increased the risk of developing evaporative-type dry eye syndrome due to the reduced blink rate.
Incomplete Blinking
An incomplete blink is when the top and bottom eyelids don’t meet during a blink, leaving some of the eye’s surface exposed. This can reduce the quality of the lipid layer in the tear film and eventually lead to dry eye syndrome.
Research published by the American Optometric Association (2014) found that people are significantly more prone to incomplete blinking when reading on a computer screen than when reading from a hard copy.