What is Dry Eye Disease?
Dry eye is a condition in which there are insufficient tears or poor quality tears to lubricate and nourish the eye. Tears are necessary for maintaining the health of the front surface of the eye and for providing clear vision. People with dry eyes either do not produce enough tears or have a poor quality tear. Dry eye is a common and often chronic problem, particularly in older adults. Dry eye can also result from an improper balance of tear production and drainage problems.
- Inadequate amount of tears – Tears are produced by several glands in and around the eyelids. Tear production tends to diminish with age, with various medical conditions, or as a side effect of many medications. Environmental conditions such as wind and dry climates as well as indoor environments can also affect tear volume by increasing tear evaporation. When the normal amount of tear production decreases or tears evaporate to quickly from the eyes, symptoms of dry eye can develop.
- Poor quality of tears – Tears are made up of three layers: an oily layer, an aqueous layer (water) and mucus (a sticky layer). Each component serves a function in protecting and nourishing the front surface of the eye. A smooth oil layer helps to prevent evaporation of the water layer, while the mucin layer functions in spreading the tears evenly over the surface of the eye. If the tears evaporate too quickly or do not spread evenly over the cornea due to deficiencies with any of the three tear layers, dry eye symptoms can develop.
The most common form of dry eyes is due to an inadequate amount of the water layer of tears. This condition, called keratoconjunctivitis sicca (KCS), is often referred to as “Dry Eye Syndrome” or “Ocular Surface Syndrome”. People with dry eyes may experience symptoms of irritated, gritty, scratchy, or burning eyes, a feeling of something in their eyes, excess watering, and blurred vision. Advanced dry eyes may damage the front of the eye and impair vision. Treatments for dry eyes aim to restore or maintain the normal amount of tears in the eye to minimize dryness and related discomfort and to maintain eye health.
What are causes of dry eyes?
The majority of people over the age of 65 experience some symptoms of dry eyes. The development of dry eyes can have many causes. They include:
- Age – dry eye is a part of the natural aging process. The majority of people over age 65 experience some symptoms of dry eye.
- Gender – women are more likely to develop dry eyes due to hormonal changes caused by pregnancy, the use of oral contraceptives, and menopause.
- Medications – certain medicines, including antihistamines, decongestants, blood pressure medications and antidepressants, can reduce the amount of tears produced in the eyes.
- Medical conditions – persons with rheumatoid arthritis, diabetes and thyroid conditions frequently experience symptoms of dry eye.
- Environmental conditions – exposure to smoke, wind, dry climates can all increase tear evaporation resulting in dry eye symptoms. Failure to blink regularly due to tasks involving prolonged close work like reading or viewing a computer screen can also contribute to drying problems.
- Finally, many other factors such as the long term use of contact lenses can be a factor in the development of dry eyes. Refractive eye surgeries, such as LASIK, as well as cataract surgery can be causes of dry eye symptoms.
Please visit our office to learn more about the diagnosis and treatment of dry eye syndrome.