Dry eye

What is dry eye?

Dry eye is a condition that commonly affects people of all ages.

The tears have several important functions:

• They keep the front surface of the eye (the cornea) moist and comfortable which helps to keep the vision clear.  If it starts to dry out, the vision will start to blur.

• They wash away debris and waste products from the eye, and help clear away small foreign bodies and dust that may get into the eye.

• They provide nutrients to the eye to keep it healthy, and carry substances that help to prevent or fight infection.

The tear film is normally spread over the eye with each blink.  Most people blink about once every 12 seconds.  If the tear film evaporates too quickly, or is not produced in sufficient quantities, the eye may dry out between blinks.

What are the symptoms of dry eye?

The symptoms of dry eye vary from person to person, but those whose tear production is inadequate usually experience one or more of the following symptoms:

• Blurred vision
• Sore or stinging eyes
• Sandy, gritty or scratchy eyes
• Foreign body sensation
• Burning or irritated eyes
• Sensation of dryness
• Persistently watery eyes
• Red eyes
• Decreased tolerance to contact lenses

What causes dry eye symptoms?

Most people’s eyes tend to become drier as they age, but the degree of dryness can vary.

• Other causes of dry eye are:
• Dry or windy weather, air conditioning and heaters may change the evaporation of tears from the surface of the eye.  Cigarette smoke may cause irritation.
• We tend not to blink as often if we are concentrating.  Using computers, watching television, driving or reading may cause irritation if the tear film is unstable.
• Wearing contact lenses may result in changes in tear film stability and evaporation.  Symptoms of dry eye are one of the major reasons why people stop wearing contact lenses.
• There is a normal reduction in tear production as we age.
• Hormonal changes during pregnancy and after menopause may result in changes in tear film stability and tear production.
• Medications including antihistamines, contraceptives and anti-depressants may alter tear stability.
• Arthritis may be associated with dryness of mucous membranes and tear film instability.  Sjogren’s syndrome is a condition characterized by rheumatoid arthritis, dry eyes and a dry mouth.

How is dry eye diagnosed?

Your eye care practitioner will conduct tests that investigate tear production and tear evaporation.  They may instill dyes into the eye that allow detection of areas of dryness or irritation.

What is the treatment for dry eye?

Mild dry eye is treated by using ocular lubricants or tear supplements.  Tear supplements do not cure dry eye; they provide symptomatic relief by effectively replacing the tears, moisturising and lubricating the eye.

There are many different tear supplements available, the most common being drops.  Sometimes a gel or ointment may be preferred in moderate or severe cases of dry eye.  Your eye care practitioner can recommend the tear supplement which is best for you.

What else can be done to reduce dry eye symptoms?

• Avoid environment conditions that may aggravate the condition.
• Wear wrap around sunglasses to protect your eyes from the drying wind.
• Take frequent breaks when working on computer.
• Blinking more frequently may be helpful.
• Cold compresses or bathing the eyes periodically with saline may also be beneficial.

Visit or call one of our centres if you are concerned about the health of your eyes or would like to book an appointment for an eye examination.