Dry Eye

Symptoms of eyes feeling irritated, tired, watery and uncomfortable are very common.

Often this occurs when driving, reading, using a computer, or watching television.

These symptoms are usually due to tear dysfunction and poor lubrication of the surface of the eye, often called dry eye (although the eyes often may paradoxically water due to reflex tearing). There are many degenerative processes that affect the function of tears as one ages. These include changes in the eyelids and on the surface of the eye itself. When the tears do not lubricate the surface of the eye adequately it becomes uncomfortable and the eyelids tend to want to close, making the eyes feel tired. Vision may also be affected and be variably blurry.  These changes may occur at a younger age for some than others. The problem is partly genetically determined but also due to the environment. Long-term ultra-violet light exposure, as well as exposure to wind, dust, or other ocular irritants probably contribute to the trouble.

These problems are made worse by anything that increases evaporation of tears from the surface of the eye – typically wind, air-conditioning, or heating. The film of tears on the surface of the cornea (the clear part of the eye on the front) has to remain smooth and stable between blinks to keep vision good as well as to keep the eye comfortable. In ordinary circumstances we blink 10 or 12 times each minute, so the film of tears is replaced every few seconds. When we read, watch television, look at a computer screen, or do other visual tasks involving some concentration, such as driving, the rate of blinking reduces to as little as 3 or 4 times a minute. The film of tears then has to stay stable for 15 seconds or more. In young, healthy eyes this is fine but as we get older the components of the tears are not as good and the tear film breaks up much more quickly. Then the eyes start to feel uncomfortable.

What can be done about it?

Unfortunately, we cannot turn back the clock and the ageing changes in the eye and eyelids cannot be reversed. Although some things can be done to help alleviate the problem, there is no cure as such. Some, or all, of the following measures may be helpful:

Ocular protection

Protecting your eyes from wind and sun can reduce evaporation from the surface of the eye. Wear a hat and well-fitting wrap-around sunglasses when outside. Avoid direct air-conditioning or heating if you can (e.g. direct the air vents in the car away from your face).

Ocular lubricants

Lubricating eyedrops can help to keep your eyes comfortable. It is best to use those with no preservatives (in single-use or special containers – Optive Fusion, Systane Hydration, HyloFresh, HyloForte, TheraTears, BionTears, Oculocin Propo) or with “disappearing” preservatives (Luxyal, Optive Fusion, Blink Intensive Tears, Genteal, Vistil). Preservatives in eyedrops can be toxic to the surface of the eye when used for prolonged periods. Thicker drops (Systane Ultra SDU, Refresh Liquigel, Genteal Gel, Polygel) last for longer but tend to make vision blurrier for longer and are most helpful at night. People generally prefer one drop or another for no specific reason other than the way they feel. Try several different drops to see which feels the best for you. You may need to use them very frequently.

Eyelid hygiene

Debris on the edges of the eyelids can cause irritation and clogs up the openings of the meibomian glands in the eyelids. These glands produce the thin, oily surface layer of the tear film that prevents tears evaporating. This debris may be skin material like dandruff, hardened oil secretions, or from make-up. Such debris can also harbour bacteria that release inflammatory chemicals into the tears. If you have you have been told that you have this then gently clean the edges of the eyelids daily with Sterilid (made by TheraTears). In the longer run you may only need to do this once or twice a week. Minimise the amount of make-up or cosmetics that you use on the eyelashes and eyelids as that contributes to continuing irritation. Any make-up on the lids should be completely removed each night.

Heat & massage

Using some gentle heat and massage on the eyelids can help to open up the meibomian glands and reestablish the oily outer layer of the tear film. This helps to reduce evaporation of the tears and disruption of the tear film between blinks. Soak a thin cloth or flannel in hot water and squeeze it out (or heat it in microwave – but make sure it is not too hot). Hold it on the closed eyelids and massage the eyelids gently through it until it cools off. It should not be too hot and do not rub hard, It should feel comfortable. See:  www.thermaleyes.com.au

Omega-3 fatty acid supplements

Taking omega-3 fatty acid supplements (e.g. Lacritec, fish oil, flaxseed oil) can help in the long term. These have an anti-inflammatory effect on the surface of the eye and eyelids in high enough doses and improve the function of the meibomian glands in the eyelids. Take at least three 1,000mg capsules (or equivalent) of a combination of fish and flaxseed oil, indefinitely.

Tears Again Spray / Optrex Actimist

These products are the same and mimic the effect of the oil from the meibomian glands and stabilise the tear film and reduce evaporation. You spray these onto your closed eyelids 3 or more times a day. It gets in around the edges of the eyelids and into the tear film, where it works. You need to use it regularly for it to be effective. It generally does not make the eyes feel better immediately but with regular use makes them more comfortable and can reduce the need for eyedrops.

Computers, reading, television

Frequency of blinking decreases whenever you are concentrating on a visual task such as reading, using a computer, watching television, or driving and may be as low as 3 times per minute. This is an unnatural situation for the eyes. When doing these activities it is important to take frequent, short breaks to give the eyes a rest and to allow them to blink and move naturally for a while. Even a break of a minute every half hour or so can give some relief and allow you to continue for longer. Stand up and move away from your position and your eyes will start to move naturally again. Try looking out of a window, or as far away as you can, to allow the focussing mechanism in the eyes to relax, then return to what you were doing. Although you may lose a few minutes of work during the day you will probably increase your productivity and your eyes will feel more comfortable at the end of the day.

Other treatments:

Closing off the tear drainage ducts in the eyelids (punctal occlusion) can help those with severe dry eye but does not help those with evaporative dry eye problems. Intense pulsed light (IPL) can be used to try to improve meibomian gland function where that is an issue. (See www.dry-eyes.com.au)

Experience Life Clearly

Dr. Steven Wiffen is a consultant ophthalmologist subspecialising in cornea, cataract, laser and refractive surgery.