What is Dry Eye?
Dry eye is a medical condition that affects an estimated 20 million people in the United States alone. Dry eye most often results from inadequate lubrication of the eye. Symptoms may be occasional discomfort or chronic and potentially vision-threatening, whether mild or painful. Only your eye care specialist can properly diagnose your dry eye problem.
The Importance of Eye Lubrication: Tears and Tear Film
Good vision starts with good tear film that must constantly be produced and spread over our eyes to keep them moist.
Tear film:
- bathes, refreshes and protects the surface of the eye from the irritating effects of dirt, dust, and other airborne particles
- protects from infection
- helps to create a smooth surface so vision stays clear and undistorted
- keeps eyes lubricated and comfortable
If you have an abnormal or deficient tear film, the quality of your vision may be diminished. Tears are made up of 3 components: lipid, aqueous and mucins. Each component must be in balance to create the necessary moisture to keep our eyes comfortable. If any component is missing or damaged, the tear film is compromised and the eye moisture will be depleted causing the eyes to feel dry and irritated.
Chronic dry eye can occur when the tear glands don’t produce the right quantity or quality of tears to keep the eyes lubricated and protected.
Characteristics of Dry Eye Syndrome
Dry eye syndrome is one of the most common reasons people visit an eye health professional. It occurs most often in the elderly; as we age, the eyes naturally produce fewer tears. However, sometimes, the lipid and mucin layers produced by the eye are so unstable that tears can't remain on the eye long enough to keep it lubricated. Consequently, some people with dry eye may actually have tears running down their cheeks! Dry eye syndrome, also called keratoconjunctivitis sicca or dysfunctional tear syndrome, is the result. In some people, dry eyes result from an imbalance in the composition of their tears or an inability to produce enough tears to keep their eyes sufficiently lubricated. In addition, eyelid problems, environmental factors, certain medications and other causes can lead to dry eyes.
Symptoms of Dry Eye Syndrome
Dry eye syndrome most commonly occurs in both eyes, but may affect one eye more than the other. Common symptoms include:
- Eyes that sting or burn, feel scratchy, become irritated and tear excessively
- Blurred, changing or decreased vision.
- Pain and redness in the eye
- A feeling of heavy eyelids
- Mucus in or around their eye
- Difficulty wearing contact lenses.
- People with more severe cases of dry eye often are also sensitive to light.
More commonly, people with dry eye have fluctuating vision and experience problems with tasks requiring visual concentration such as reading, using a computer and driving. Most people with dry eye find the condition to be an uncomfortable nuisance, with many characteristics of a "chronic pain" type of syndrome.
Common Causes of Dry Eye
There are many causes of Dry Eye. These can be attributed to a number of different factors:
Aging: As we grow older, our eyes produce tears that have less natural oil in them.
Menopause: Females entering menopause are among the most prone to dry eye.
Autoimmune Disorders: Diseases such as rheumatoid arthritis, lupus, multiple sclerosis, thyroid and Sjogren's syndrome can cause inflammation in the tear-producing lacrimal gland.
Environment: Excessive heat or air conditioning, fans, dry or windy climates, smoke, airplanes, and lack of sleep can all cause dry eye.
Work Environment: Outside wind, dust, heat, or smog can cause dry eye. Focusing on a computer screen for extended periods is also a common cause.
Medications: Numerous medications can cause dry eye. Be sure to tell your eye care specialist about all the medications you are taking.
Eye Medications: Preservatives in artificial tears and anti-glaucoma drops may be toxic to the cells on the surface of the eye and contribute to dry eye.
Contact Lens Wear: Wearing contact lenses can contribute to dry eye.
Treating Dry Eye Syndrome
Although dry eye syndrome has no cure, its symptoms can be treated.
- Artificial Tears: Over-the-counter artificial tears that lubricate the eye are the main treatment.
- Other Treatments: Eye ointments, antibiotics (both oral and drops) and avoiding environmental triggers such as hair dryers and rooms with low humidity.
- Restasis: In 2002, the U.S. Food and Drug Administration approved the first prescription treatment for dry eyes, called Restasis (cyclosporine ophthalmic emulsion 0.5%). This treatment increases the body's ability to produce its own natural tears by treating one of the underlying causes of the disease—inflammation.
- Punctal Plug: In cases of moderate to severe dry eye, tears can be conserved by placement of a temporary or permanent punctal plug into the channel at the inner corner of the eyelid where tears drain into the nose and the back of the throat.
- Surgery: And in some cases, a surgical procedure to close the tear ducts is in order .
