What is the Cornea?
Many people suffer from the nagging symptoms of dry eyes. The eyes may feel tired, burn, water, and feel like sand is in them. These feelings are often provoked by situations that make us stare, such as watching TV, reading or doing detailed work. Also, anything that increases evaporation can elicit the symptoms, such as being outside in the sun, wind, in the car in front of a heater or air conditioner.
The symptoms from dry eye syndrome are often misdiagnosed as allergy or infection. The causes for the condition are variable, but usually fall into three categories:
- Decreased tear production
- Abnormal tear chemistry
- Abnormal lid position or tear duct function
Decreased tear production occurs to some degree as we age, and also occurs in association with autoimmune diseases such as Grave’s disease and rheumatoid arthritis. Drugs such as antihistamines, antidepressants, and diuretics also decrease tear production. Females are more prone to dry eye syndrome and there is some evidence in the literature that HRT (hormone replacement therapy increases the frequency of dry eye.
A more common reason for dry eyes is abnormal tear chemistry. Our tears are made primarily of salt water, mucous, and oil. If any component is lacking or abnormal the tears produced break up quickly – and the consequence is dry eye. The most common culprit is the oil component of the tear film. Many people produce oil that is too viscous or insufficient.
Lastly, the eyelids are the “windshield wipers” that are responsible for circulating and spreading the tears that are produced. Any abnormality of their function or position can therefore cause dry eye syndrome.
Dry eye syndrome is a common affliction. It usually does not threaten the health of the eyes unless the dryness is severe. It does, certainly, make the eyes uncomfortable and can cause the vision to be blurred. Treatment of the condition is based upon the underlying cause, and may include artificial tears, lid hygiene, and rarely, lid surgery. Also, new nonpreserved tears and punctal plugs are now available which have proven very helpful. The plugs are placed in one of the tear ducts during an office visit, and make it so the tears that are naturally present do not drain away so quickly. Help is available for dry eyes – please contact us if you would like an evaluation.