Yes, everyone gets dry eyes – that’s why we blink.
Your eyes have a tear layer over the eye surface that helps protect it and stop it drying out. This tear layer is in fact three minute separate layers that perform different tasks, but without getting to medical, suffice to say the overall layer provides both physical as well as bacterial protection.
To keep the eyes moist and lubricated the eyelids must blink over the eye surface – but the eyelids in order to slide over the eye surface easily without discomfort themselves need lubrication – a chicken and egg situation.
If this process is compromised in any way then dry eyes result, with symptoms varying from the very mild and slightly annoying through to the extreme severe needing medical attention even surgery (but not very often fortunately). In the majority of cases of dry eyes the treatment is straightforward and effective.
Causes of Dry Eyes
Sometimes referred to as Dry Eye Syndrome, eye dryness can be due to a variety of reasons – environmental, organic, age-related and/or medication.
Environment is probably the main cause, with THE main cause in the category today being staring at computer screens, why it’s even got its own syndrome – Computer Vision Syndrome.
The problem instigated by working at a computer screen is one of staring at the screen for long periods which change the frequency of blinking of the eyes – necessary remember to lubricate them. Normally we blink every 3 seconds, but when staring at a screen we don’t blink until every 10 seconds – around three times less. The eyes just can’t cope with the lack of lubrication and the tear layer evaporates and dries out!
Not to worry – this problem is easily solved by adopting some well used techniques coined by the phrase “The 20-20-20 Rule” which says:
Every 20 minutes focus on something 20 feet (6 metres) away for 20 seconds (and to this for good measure you could add – blink 20 times).
Another environmental cause is dry atmosphere, and in this case we can have both natural and man made causes. A dry atmosphere evaporates the liquid on the eye surface, so of course dry, sometimes arid geographical areas like the North West of Australia, together with associated dust, cause real dry eye problems.
The man made equivalent comes from the increased use today of air conditioning in homes, car and the worst of all, airplanes. Who hasn’t flown for a few hours only to land with dry eyes, after being subject to re-circulated cold very dry air? (A simple way to prevent dry eyes is to drink plenty of water and direct air jets away from the face, in addition that should stop sinuses from drying out.) Using lubricating eye drops throughout the trip is also helpful in alleviating the discomfort.
Fortunately smoking is banned in public areas in many countries, but smokers themselves are subject to dry eyes whilst maintaining their habit. The simple way to prevent dry eyes this time being even simpler – stop smoking!
Organic causes of dry eyes include the various glands that produce the tear layer components not functioning properly. Although this sounds serious, it can sometimes be helped by blocking up the exits with tear drain plugs.
Age and Medication
Nothing gets better with age except maybe a good red wine. Age related hormonal changes cause significantly more dry eyes in women compared to men. The ratio being roughly 4 women to 1 man.
With age of course comes an increased use of a wide variety of medications, and with that the likelihood of side effects, one of which is, you guessed it – dry eyes. Typical medications thought to induce dry eyes are anti histamines and decongestants, which of course actively dry membranes, so no surprise there.
Other drugs that might do the same are beta blockers, diuretics, sleeping pills, birth control pills, anti-depressants and some antibiotics.
Treatment of Dry Eyes
Medical interventions, if that’s what we can call them, also produce dry eyes, notably the use of contact lenses and laser surgery to correct vision. Fortunately optometrists are well placed to advise and treat in these situations.
Treatment of dry eyes varies according to the severity of the condition.
With a mild form of dry eyes for example it may be a simple matter of education, especially if environmental causes are at play, computers and air conditioning. Mild over the counter (OTC) drops can give quick and lasting relief, but longer term symptoms need more investigation.
A more prolonged use of eye drops for dry eyes involving application four times a day or more needs consideration as to whether drops should contain preservative or not – again the eye professional’s advice should be sought. When in doubt always choose a non preserved eye drop.
Dry eyes typically also involve significant inflammation, which causes both conjunctivitis (inflammation of the conjunctiva) and keratitis (inflammation of the cornea). Treatment in moderate cases often requires prescribed topical anti-inflammatories such as steroids and or cyclosporine. Your therapeutical trained optometrist is the best person to consult for these.
Severe cases of dry eyes are still readily treated by relatively minor surgical procedures. On occasion where dry eyes are severe and persistent, it remains likely that active management will provide a satisfactory outcome.
Dry eyes is such a huge topic that we have devoted a whole website to it. This will be live sometime in 2012.