Tackling dry eye means dealing with inflammation
An international workshop involving a global team of experts published a new definition for dry eye disease, and with this definition came a whole new way of managing this increasingly common problem.
This new evidence-based definition recognised the complex nature of dry eye disease and that many factors were at work. These factors worked together to upset the delicate natural balance or homeostasis of the ocular environment. Perhaps the single most important change, in terms of management, to the existing definition was the introduction of the word ‘inflammatory’.
In this article the Dry Eye Zone sets out to let dry eye sufferers know more about what this means, how you detect it and what you can do about it.
What do we mean by inflammation?
Inflammation is part of your body's natural defence mechanism. In the case of dry eye it is a response to changes in the ocular environment, such as your tear film becoming too salty, which then triggers a process by which the immune system recognizes and attempts to rebalance these potentially harmful changes.
Studies have identified some of the chemicals released in the immune response. Collectively these small proteins are called cytokines and include IL-b, TNF-a and MMP-9. It is these chemicals which result in many of the symptoms which dry eye sufferers experience such as itchy, gritty, red, irritated eyes. However, some people do not experience any of these and they are known as ‘asymptomatic’ sufferers.
If left untreated, in both symptomatic and asymptomatic cases, the inflammation can cause long-term damage to the surface of the eye, hence the use of the term dry eye disease.
How can you optician measure inflammation?
Your eye care practitioner will be looking for clinical signs of inflammation during your eye examination. This could be visual fluctuations, reduced tear volume or blocked meibomian glands to name just a few. A more reliable method than clinical signs alone is to measure level of the cytokines released in the immune response, such as MMP-9. Elevated MMP-9 levels have been shown in dry eye sufferers and act as a sensitive biomarker for inflammation.
Some practitioners, with a specialisation in dry eye, use a device called InflammaDry®. It looks and works in a similar way to the COVID-19 lateral flow tests we are familiar with. You can see it being used here.
InflammaDry recognises elevated levels of MMP-9 to identify those people that may otherwise be missed with other dry eye testing methods. This will give accurate results in as little as 10 minutes. This level of certainty will help to guide your optician in their recommendations for management.
InflammaDry gives a rapid and accurate measurement of the inflammatory marker MMP-9
Strategies to reduce inflammation
Since the recognition of dry eye as an inflammatory condition there have been new pharmaceutical therapies, your eye care practitioner will be able to advise you if these might be an option for you. However, by helping to restore your eyes natural healthy environment and therefore removing the triggers you can break the ‘inflammatory vicious cycle’. This will mean inflammatory indicators such as MMP-9 will fall.
Because dry eye disease is a multifactorial condition a more holistic approach is needed to get the best outcome. This is why your practitioner will most likely be asking you to do a range of things.
The anti-inflammatory role of omega-3 essential fatty acids is now increasingly well documented. Your body cannot make these oils, they need to be obtained from your diet, so consider adding an extra portion of oily fish to the weekly menu or start taking omega-3 supplements. But like any dietary change you do need to be patient as the benefit might not be felt for several weeks.
Reduce the saltiness of your tears by regular use of an eye drop with a hypotonic or hypo-osmolar formulation such as HydraMed. The level of salts or electrolytes in this type of eye drop is lower than many others in order to have a diluting affect.
Then, if needed, slow the rate of tear evaporation by getting your meibomian glands working better with heat treatment using a hot compress. The Dry Eye Zone now offers a new ‘eyes open’ compress which allows you to freely move about. This makes it far easier to follow your practitioner’s advice. Ideally this is followed by deep cleansing to unblock any clogged ducts and get those oils flowing. Some dry eye specialists will do this for you as an in-practice therapy. It might be worth asking at your next appointment if you are having on-going problems.
And don’t forget those really simple measures you can take like drinking an extra glass or two of water, turning down the heating a little.
It might sound like a lot but you will feel the benefits and after all, a multifactorial condition, requires a multi-pronged approach to relief!
If you are experiencing dry, tired feeling eyes then you should ask the advice of your eye care professional. There is no substitute for regular check-ups to help keep your eyes healthy.
InflammaDry is a registered trademark of Quidel Inc.
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InflammaDry® is the only rapid, in-practice test to aid in dry eye diagnosis
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