Most people who work in an air-conditioned office and spend long hours staring at a computer screen will have experienced this sensation at some point towards the end of their work day. It is usually caused by ‘dry eye’ where the eye surface dries and becomes inflamed. It is a common condition affecting 1 in 4 people in the UK, and while it is not a serious condition, it tends to require ongoing treatment on a long-term basis.
Who gets dry eyes?
Dry eye affects people of any age, but the chances of developing the condition are higher among certain groups. This includes older people, women experiencing hormone changes and those who use certain medications (e.g. antidepressants). Dry eye can also occur after certain types of laser surgery, but it is usually self-limiting as damaged nerves regenerate over the coming weeks to months.
Each time you blink, a thin layer of tears (tear film) spreads like wipers across the surface of your eye, helping to maintain good health and clear vision. The tear film is made up of 3 layers:
- A mucus-like layer that sits on the eye surface – helps to keep the other layers adhered to the eye
- A middle watery layer – moistens the eye and helps wash away debris
- An oily layer that sits furthest from the eye surface – provides a seal similar to the effect of oil on water, which keeps the underlying watery layer in place for as long as possible. The oil is produced by 20-30 tiny ‘meibomian’ glands that are located just behind your eyelashes and along your eyelids.
When one or more layer is of poor quality or lacking in thickness (e.g. in an eye prone to blockage of ‘meibomian’ glands), the tears can’t cover the eye surface adequately leaving it exposed and dry.
How does it affect my eyes?
People experience dry eye in a range of ways – from mild redness and irritation to grittiness, burning and foreign-body sensation (a phantom sensation of ‘something in the eye’). It often surprises people that a common symptom of dry eye is watery eyes! This is caused by ‘reflex tearing’, where our eyes overproduce tears in an attempt to alleviate the dryness. While this should be helpful, these ‘reflex’ tears are of poor quality and drain away quickly. This means they do little to improve eye comfort and can blur your vision. The vision can fluctuate further with rapid drying of the tear layer, which creates the illusion of looking through a frosted window in between eye blinks.
What can I do to prevent dry eyes?
Here are some steps you can follow:
- Make changes to the room environment – dry environments such as air-conditioned offices and hot, dusty settings can increase the loss of tears from the eye surface. You can tackle this by setting your central heating to a lower temperature and or using a humidifier to add moisture to the air. When venturing outdoors, wear wrap-around spectacles or sunglasses for protection.
- Take regular breaks from detailed work – people who use a computer for long hours tend to blink less frequently and completely, causing poor coverage of tears across the eye surface. Follow the 20:20:20 rule to allow your eyes to rehydrate and rest – every 20 minutes, change your eye focus from your screen to something in the distance (approximately 20 feet or 6m away), for approximately 20 seconds, blinking completely a few times to help the spread of protective tears. For every hour of work, take a 5-minute break away from your desk to stretch your legs and keep hydrated by drinking water.
- Eat a balanced diet – omega 3 and 6 can help maintain the oily top layer of your tears. Foods that are rich in these nutrients include oily fish, flaxseed, linseed, nuts, and seeds. The evidence for taking supplements is conflicting – ensuring that these nutrients are part of your balanced diet is enough.
- Keep your ‘meibomian’ glands clear and unblocked – these tiny glands run along your upper and lower eyelids, opening at the lid margin where they produce an oil that protects your eye surface. You can help to keep these glands clear and open by applying warm compresses to your closed eyes for 5-10 minutes, and gently massaging your eyelids to push out blocked material. Using a microwaveable heat pack will make the process easier and quicker, so your form a habit as part of your daily hygiene routine. You should also try and avoid using eye make-up such as mascara and eyeliner, and take extra care not to apply liner along the inside lining of the eye where the glands emerge.
- Keep your eyelashes clean and healthy – some people have a condition called ‘blepharitis’ which causes inflammation of their eyelids and dandruff-like crusting at the bottom of their eyelashes. Daily targeted cleaning of the lids and lashes helps to remove crusting, bacteria and debris, and keep the small glands that produce the oily layer of your tears clear and open. There are a range of cleaning solutions and pre-prepared wipes readily available from the pharmacy to make this process easier, and help form a habit as part of your daily hygiene routine.
What can I do to relieve the symptoms of dry eyes?
There is a wide range of artificial tear drops, gels, and ointments readily available to alleviate the symptoms of dry eye. Keep in mind that their purpose is to supplement your natural tears, and not to treat the underlying cause of dry eye. Many preparations are preservative-free, and they do not contain active ingredients such as antibiotics. This means you can use them regularly on a long-term basis without harming your eye health. You may need to try a few preparations to find the combination that works best for you. For example, a person with pronounced dry eye may use drops/ gels every 4 hours during the day and ointment before bed. Here are some recommendations:
- Drops – provide rapid relief of symptoms without affecting your vision. They are slightly thicker than your natural tears and need to be instilled regularly as they do not retain in your eye as long as gels or ointments. Some well-known brands are: Hypromellose, Systane, Hylo-tear, Hylo-Forte, Hycosan and Hyabak.
- Gels – these preparations are thicker than eye drops, and are designed to retain in your eye for longer. This means you don’t have to use them as regularly but they may cause temporary blurring of your vision. Some well-known brands are: Viscotears and Lubristil.
- Ointments – these preparations are thick and sticky, and usually need to be squeezed from a tube. They will blur the vision for several minutes after application, so they are predominantly used before bed to protect the eye surface from exposure as you sleep. Some well-known brands are: Lacrilube and VitA-POS.
