Blinking an eye may seem a simple action, but in this issue, we learn how imperative it is for eye health. Professor James Wolffsohn, Chair of Optometry and associate pro-vice-chancellor of Aston University, casts a fresh pair of eyes on Dry Eye Disease and explains the role of blinking in relieving symptoms. Here, he speaks to Ellen Rossiter, about the research work ongoing to define and treat the condition.
Dry Eye dilemma
“Affecting hundreds of millions of people around the world, Dry Eye is one of the most common reasons for a visit to an eye care practitioner,” explains James, “and given the volume of people affected, finding effective preventative measures and treatments is vital.
“Resulting in dryness and inflammation of the cornea; Dry Eye Disease is caused by a chronic lack of lubrication and moisture on the eye’s surface. Typically, the disease causes irritation, soreness and sometimes even watery eyes.
“Left untreated, the disease can cause damage to the eye’s surface, and in some instances, vision problems. However, when you look at the ocular surface, some patients with severe damage have relatively few symptoms, meaning cases are often not picked up until later in the disease’s progression.
“Estimates for the numbers of people affected range from 5% to 50% of a population in different parts of the world, with most studies estimating around 15% of Caucasians and 30% of Asians have the disease. A lot of clinical trials, however, have previously failed to standardise what they are looking for, so the prevalence and severity of the disease remains a topic for debate.
“The variation in world-wide figures is thought to be down to several factors including a lack of uniformity in the diagnosis criteria and the impact of environmental factors such as humidity. So part of our work has focused on creating clear criteria for diagnosing Dry Eye.”
“Taking over two years and involving over 150 experts, the Dry Eye Workshop II of the Tear Film and Ocular Surface Society has worked to achieve a global consensus concerning the multiple aspects of the disease.
“As well as updating the definition and classification of Dry Eye Disease, those of us involved, evaluated the information available on the distribution, development, processes and impact of the disease.
“With the work that’s been done, we’ve now classified a spectrum between two types of the disease, one where the eye doesn’t produce enough tears and one where tears aren’t retained for long enough by the eye largely due to evaporation.
“The review of all the science on the disease to date identify around 50 possible treatments and a huge matrix of information about their effectiveness, but there is still a lack of clarity about which should be used for a particular patient. Much better guidance on treatments is required, so people have certainty about which to choose and for how long it should be used.
“When we look at artificial tears alone, there are hundreds of options available, so we’ve looked at which treatments work, for whom and what are the most effective components. As a result of this research, we’re developing new artificial tears to treat the condition.”
“Dry Eye Disease tends to be experienced by people working in air-conditioned environments, who wear contact lenses or who work at computer screens and it’s typically associated with those aged over 50.
“A worrying trend has recently emerged of young people suffering from the condition, presumed to be due to their prolonged screen time. Spending too much time at a computer, looking at a phone or tablet, is known to affect the frequency and completeness of our blink rate, which in turn affects the tear film.
“Blinking may seem a straight forward action we take for granted, but it’s one of the body’s great defence mechanisms and has many benefits for eye health. Increasing moisture, fighting infection, flushing debris, clearing vision, maintaining comfort and restoring the transparency of the cornea are all brought about by blinking.”
“Blink exercises are thought to be effective in reducing the disease’s effects but there is no research to show this is the case, so in one study we are evaluating the optimum way to carry out blink exercises and the frequency with which they should be carried out.
“We’ve also developed an app which patients can use to establish if they are likely to have Dry Eye Disease called the blink test, which has proven a quick and accurate way to identify the disease and particularly helpful where clinicians don’t have access to advanced instrumentation.”
A broader view
“Investigating Dry Eye Disease is just one facet of our Ophthalmic research at Aston; we’re working to advance our understanding of many aspects of the development, use, preservation and restoration of ocular function.
“As well as the tear film, my research focuses on intraocular lenses (used in cataract operations), contact lenses, developing ophthalmic instrumentation and the impact of ageing on eyesight.
“We know people tend to experience a loss of eye focus around the age of 40 and glasses with varifocal lenses often assist with the challenges this brings. Given the popularity of contact lenses, developing varifocal options has been a priority.
“In some instances, the options available, are associated with blurred vision at some distances and scatter of light such as when night driving, so this is another of our research area. Light levels and distances can all prove problematic for varifocal contact lens wearers, so we’re working on reducing the loss of contrast and optimising how these lenses work.
“Another huge area of interest is myopia or short-sightedness, as an increasing number of people are affected; in some areas of Asia, for example, it’s estimated that 95% of children are short-sighted.
“Over the last decade, there’s been a growing understanding of what causes short-sightedness, so there is much research underway about how best to prevent, slow or halt the progress of myopia and the eye damage it causes.”
Looking to the future
“In terms of inspiring the next generation, I’d say the great thing about STEM subjects is the sheer variety of careers to which they open doors. Optometry itself offers great opportunities for those interested to go down that path and given our work often improves peoples’ quality of life, quickly, it is deeply rewarding.
“Clinicians are much like engineers, providing solutions for the challenges faced in healthcare. As well as understanding diseases better and translating research into new treatments, much research work is about making treatments accessible.
“Not all medical advances depend on cutting edge technology or are expensive. One of my most surprising findings was discovering how effective a heated bag of beads placed over the eyelids for 5 minutes in the morning and evening for 2 weeks was in restoring the tear film. Sometimes it’s the simplest things that work best.”