Dry eyes, sometimes referred to as dry eye syndrome or keratoconjunctivitis sicca, occur when the tear glands don't produce enough liquid or when the consistency of the tears causes them to rapidly evaporate. When normal tear production is compromised, the protective layer of fluid that normally protects the eye weakens or is destroyed.
Types
According to the National Eye Institute, there are two main types of dry eye. Aqueous tear-deficient dry eye occurs because of a deficiency of the liquid part of tears. This happens when there is a problem with the lacrimal glands, which are the structures in the eye that produce the fluid portion of tears. Evaporative dry eye happens when tears evaporate too quickly, a situation often caused by inflammation of the meibomian glands. These glands are found in the eyelid and are responsible for the production of the lipid component of tears.
Causes
Normal aging is a common cause of dry eyes, since the body naturally produces fewer tears as people get older. Hormone changes resulting from menopause often cause dry eyes in older women, explains the NHS. Environmental causes can include dry conditions, wind, sun and high altitude. Blinking less frequently, as is common when working in occupations utilizing visual concentration, such as reading or computer work, can be another cause. Contact lenses and laser surgery can both affect the functioning of the eyes and lead to dry eye. Some medications, including diuretics, beta blockers, antihistamines and antidepressants can also lead to the development of dry eyes. Certain diseases are also linked to dry eye, such as rheumatoid arthritis, lupus and Sjögren's syndrome.
Treatment
The first line of treatment for dry eyes typically involves treating any underlying medical condition that may be causing it. Eliminating or reducing the impact of environmental factors is another way to treat mild cases of dry eye. Over-the-counter tear substitutes or lubricating ointments can be used for occasional instances of dry eye. For severe dry eyes, anti-inflammatory medication may be prescribed. Plugging the drainage holes in the eyes, either through the use of temporary or permanent plugs, or through surgery to permanently close them, is another option for severe cases of dry eye.
Complications
Although most cases of dry eye are mild, there are some complications associated with leaving dry eyes untreated. The inflammation resulting from dry eye can lead to scarring of the cornea. An overproduction of tears is another potential complication, caused by the eyes attempting to compensate for poor tear quality. Conjunctivitis, an inflammation of the membrane covering the eye and lining the eyelid, can also develop in individuals with chronic dry eyes.
Prevention
Preventing dry eyes involves keeping the eye area clean and protecting the eyes from environmental conditions that lead to dry eyes, such as wind and sun as well as pollutants such as cigarette smoke. Moistening indoor air with a humidifier can help keep eyes from drying out, and aiming anything that blows air, like air-conditioners or hair-dryers, away from the eyes is a good preventive measure. Some people also try adding more omega-3 fatty acids to the diet, since omega-3 fats are used by the body for tear production.
