The continuous production and drainage of tears is important to the eye's health. Tears keep the eye moist, help wounds heal, and protect against eye infection. In people with dry eye, the eye produces fewer tears, or tears of lesser quality, and is unable to keep its surface lubricated and comfortable.
The tear film consists of three layers--an outer, oily (lipid) layer that keeps tears from evaporating too quickly and helps tears remain on the eye; a middle (aqueous) layer that nourishes the cornea and conjunctiva; and a bottom (mucin) layer that helps to spread the aqueous layer across the eye to ensure that the eye remains wet. Dry eyes result from problems with any of the three layers of tears. As we age, the eyes usually produce fewer tears.
Dry eye, more common in females, can occur in climates with dry air, as well as with the use of some drugs, including antihistamines, nasal decongestants, tranquilizers, and anti-depressant drugs. Patients with dry eye should let their health care providers know all the medications they are taking, because some of them may intensify dry eye symptoms.
People with connective tissue diseases, such as rheumatoid arthritis, can also develop dry eye. It is important to note that dry eye is sometimes a symptom of Sjögren's syndrome, a disease that attacks the body's lubricating glands, such as the tear and salivary glands. A complete physical examination may diagnose any underlying diseases.
The main symptom of dry eye is usually a scratchy or sandy feeling as if something is in the eye. Other symptoms may include stinging or burning of the eye; episodes of excess tearing that follow periods of very dry sensation; a stringy discharge from the eye; and pain and redness of the eye. Sometimes people with dry eye experience heaviness of the eyelids or blurred, changing, or decreased vision. Individuals with dry eye may experience difficulty wearing contact lenses.
Our Cornea specialists are leading experts in the study, diagnosis and treatment of Dry Eye Syndrome. Early diagnosis is very important because progressive deterioration of the ocular surface is possible. Tests, such as Schirmer’s test, tear film break-up time, and staining of the ocular surface with certain dyes, need to be performed to diagnose this condition adequately. Blood tests may be ordered to uncover underlying rheumatological disorders in some cases.
Artificial tears, which lubricate the eye, are the principal treatment for dry eye. They are available over-the-counter as eye drops or gel drops. Sterile ointments are sometimes used at night to help prevent the eye from drying. Using humidifiers, wearing wrap-around glasses when outside, and avoiding outside windy and dry conditions may bring relief. For patients with severe cases of dry eye, temporary or permanent closure of the tear drain (small openings at the inner corner of the eyelids where tears drain from the eye) may be helpful. Medication may also be prescribed by your physician. Finally, clinical trials are underway at Mass. Eye and Ear for new therapeutic options.