What is dry eye syndrome?
This condition is thought to be caused by a problem with the quality of the tear film that lubricates the eyes.
Tears have three components: a mucus layer that coats the cornea; a middle aqueous layer provides moisture, oxygen and nutrients to the cornea; and an outer oily film, that seals the tear film on the eye and helps to prevent evaporation.
Tears are formed in small glands located around the eye. Excess tears drain into two ducts in the corner of the eye beside the nose.
What causes it?
Dry eye syndrome can have many triggers. These include ageing, exposure to dry or windy climates, air-conditioning and cigarette smoke. Reading, watching TV or computer use may trigger dry eyes in some people.
Contact lens can absorb the tear film, leading to irritation and dryness. Conditions such as thyroid problems and Parkinson’s disease can cause dry eyes. Certain medications and hormonal changes around menopause can also trigger it.
In many cases of dry eye syndrome, there may be no identifiable cause. Symptoms include itching, burning, irritation and redness. Blurring of vision can also occur. Excessive tearing may also be a problem for some people.
Diagnosis is made by measuring the production, evaporation and quality of tears produced.
Can it be treated?
There is no cure for dry eye syndrome, but a range of treatments and self-help measures can help control symptoms. Keep well hydrated and maintain a moist atmosphere by using a humidifier.
Take frequent breaks and blink often when undertaking activities such as reading or computer use. Avoid rubbing your eyes as this will only worsen the irritation.
The regular use of artificial tears can also help. These products can be watery, which alleviate symptoms temporarily, or thicker ointments that adhere to the eye longer.
Preservative-free tears are recommended as they contain fewer additives that could cause irritation.
In rare cases, surgery may be required. One type of surgery for the condition is called punctal occlusion. This involves the use of small plugs – punctual plugs – to seal the tear ducts.
Once the plugs are inserted, tears cannot drain into the tear ducts, allowing the eyes to remain moist. The procedure can be temporary or permanent depending on the type of plug used.
Prompt diagnosis and treatment of dry eye is important. Early treatment will help protect the cornea.
Complications can include scarring of the cornea, conjunctivitis, extreme sensitivity to light and vision changes.
