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With so much time spent staring at screens these days, dry eye is becoming increasingly common.
Otago ophthalmologist Francesc March is literally going to the ends of the Earth in a bid to develop improved treatments for this uncomfortable ocular issue. His research is the first to investigate dry eye in space-like conditions, onboard parabolic flights, which create short periods of weightlessness through precise flight patterns.
“Dry eye disease affects about 15% of the population and we know it’s more of a problem for people who spend a lot of time in front of a computer,” explains March, a Dunedin eye specialist and a researcher at the University of Otago’s department of medicine.
“It impacts the layers of tears that cover your cornea and occurs when you either don’t have enough tears or they evaporate too quickly.”
The tear film has three layers: fatty oils, aqueous fluid and mucus. Each time you blink, the tear film covers the eye protecting the cornea and keeping the ocular surface lubricated and smooth.
But a variety of things can disrupt the quality of the tear film, including autoimmune conditions, allergies, some medications and vitamin A deficiency. Hormonal changes in the menopause transition or during a woman’s monthly cycle can affect glands in the eyes that produce oil and fluid. And blockages of the meibomian glands, which release the oily component, can cause the tear film to evaporate too quickly.
As well as computer use, environmental changes like air conditioning, heating, windy weather and very dry climates increase dry eye symptoms. Sufferers may experience stinging, a scratchy/gritty feeling, sensitivity to light, watery eyes, redness, blurred vision and eye fatigue. Severe dry eye can lead to other problems such as corneal ulcer and conjunctivitis.
Long-haul flights, with many hours spent in the dry closed conditions of an aircraft cabin, can intensify the symptoms of dry eye. Astronauts have an even tougher time, as the lack of gravity changes the way the tear film behaves. 30% of them report dry eye symptoms.
That’s why, for the past three years, March has been travelling to Bordeaux, France, to collaborate in international research examining exactly what happens to the eye in space.
March describes working in zero gravity as a joyful experience. “It’s super comfortable,” he says. “One of the theories is that the sensation feels similar to being in the womb. In videos of me working, I’m smiling all the time.”
While looking to improve the eye health of astronauts, March also hopes there will be benefits for those of us who are earthbound.
“We can learn a lot about what happens on Earth when we study in space,” he explains. “We are working on having better diagnostics and therapeutics for dry eye.”
These could include infra-red imaging to assess the tear film along with devices such as ocular neurostimulaters to improve tear production at the push of a button.
“We want to help astronauts, but we also want to help the 700 million people around the world who suffer from dry eye,” says March. “That’s my goal.”
In the meantime, he recommends taking plenty of screen breaks. Studies have shown that a person’s blink rate can decrease by as much as 60% when using computers or other screens. Following the 20-20-20 rule can help. For every 20 minutes you look at a screen you should spend 20 seconds looking at something 20 feet away. When in doubt aim for a longer distance rather than a shorter one.
Staying well hydrated, as well as wearing sunglasses outdoors to protect eyes from wind and dust, using a humidifier in dry climates and putting warm compresses on the eye can all help reduce symptoms
Eye drops are a speedy way to lubricate the eyes but, if using these several times a day, choose a preservative-free product to reduce the risk of causing further irritation.
There are also some treatment options if dry eye persists. Lipiflow is designed to unblock meibomian glands using warmth, pulsation and gentle pressure. IPL (intense pulsed light) is also used to stimulate the glands in the eyes. And punctal plugs can be inserted to slow the drainage of tears from the eyes.
