Dry eyes

What are dry eyes? Why do we get dry eyes?

Tears are a complex combination of water, oils, and lipids, helping to lubricate the eye, wash away debris, stabilise vision, and protect against infection. Every time we blink, our tears cover the front surface of our eye, known as the cornea, keeping it hydrated and healthy. When the eyes don't produce enough tear fluid, when the quality of the tear fluid produced is poor, or when the tear fluid evaporates too quickly, we can get dry or scratchy eyes, and our eyes can become irritated and inflamed.

Dry eyes are usually harmless, although they can result in increased sensitivity and burning in the eyes. If inflammation or infection is suspected, the treatment depends on the cause, the area of infection in the eye, and the degree of the infection. If you have any worries that you may have dry eyes, blurry vision, or sore eyes, you should visit an optometrist, as you may need eye drops with antibiotics.

What causes dry eyes?

Dry eyes can be caused by several factors:

Reduced blink rates associated with visual tasks, e.g. computer use
Side effects from taking certain medication, such as antihistamines or beta blockers
Pre-existing medical conditions, including rheumatoid arthritis or Sjögren’s syndrome
Pre-existing eye conditions such as blepharitis or eyelid conditions
Hormonal changes, typically associated with being female, middle age or pregnancy
Problems with drainage via the tear ducts

There are also several non-medical and lifestyle conditions that may cause dry eyes such as:

Hot or windy climates
Contact lens wear
Smoking
Air-conditioning units
Inadequate production of tears

Tears are generated by glands around the eye and eyelids. With age, the tear production decreases. Dry eyes can also be a side effect of steroids and other medication you take to treat medical conditions. Symptoms of dry eyes develop when the tear amount levels decrease or the tears evaporate quickly. Environmental changes such as windy or dry climates may lead to dry eye conditions if the eye is not nourished appropriately.

Any activity which requires a lot of concentration, such as driving long distances or continuous exposure to screens, may cause dry sore eyes.

Quality of tears

Oil, water, and mucus are all ingredients of a tear. Each of these ingredients plays a significant role in nourishing the eye surface. The water layer is protected from evaporation with the help of the oil layer and the mucus layer disburses the flow of the tears throughout the eye surface evenly.

How are dry eyes diagnosed?

Optometrists have tests to detect and monitor dry eyes. If necessary, an ophthalmologist is recommended. We recommend an eye examination at least every two years, regardless of whether you have symptoms or established eye problems. Extreme cases may be referred to an ophthalmologist for further testing.

What you may expect during an examination:

Typically Fluorescein and Lissamine green staining drops are used for diagnosis.
A thorough history and symptoms analysis about what may be causing any dry eye problems, both systemic and environmental.
Thorough examination of the external eye and adnexa (eyelids, conjunctiva) with slit lamp biomicroscopy using various magnifications, illuminations and slit lamp techniques.

What types of dry eyes exist?

Dry eye (keratoconjunctivitis sicca) is a result of not having blinked or teared properly for longer than usual. Whatever the reason may be, tears are produced by your lacrimal gland and this should function properly to avoid dry eyes.

These are some of the medical conditions that can cause dry eyes:

Vitamin A deficiency
Lupus
Diabetes
Rheumatoid arthritis
Thyroid disorder

If you have chronic dry eyes, it may be because of one of these medical conditions.

Back to overview How to treat dry eyes?