What is dry eye (keratitis sicca)?
Most people have enough tears to keep their eyes properly moistened and lubricated. Keratitis sicca, the medical term for dry eye (it actually means "dry cornea") is an annoying condition in which there is not enough moisture in the eyes. Dry eye is more common in women than in men, and in middle age and the elderly than in younger people.
What Causes Dry Eye?
The most likely cause of your dry eyes is that you do not produce enough tears or that for some reason your eyelids do not close well, especially when you sleep. Dry eye is often related to other medical conditions, such as arthritis, or Sjogren's (show-grenz) syndrome, in which many of the body's other normally moist membranes (such as those in the mouth and nose) also lack moisture. Less commonly, it is associated with severe inflammatory mucous membrane diseases (such as pemphigoid).
What are the symptoms?
The dryness usually leads to a constant burning or foreign body sensation. Your eyes may be sensitive to light, and red and bloodshot a good deal of the time. These symptoms tend to be worse in dry climates, in dry and windy weather, and late in the day. Using a hair dryer may affect your eyes, as will dryness in air-conditioned and heated rooms, especially if you are in a draft or the direct flow of the vent, or the dehumidified cabin of an airplane. You may also have dryness of other mucus membranes, such as in the mouth and nose, or have frequent eye and eyelid infections. Many patients complain of "watery" or tearing eyes and are surprised to learn that their problem is really dryness. What happens is that as the moisture decreases, the amount of mucus increases and makes the eyes feel as if they are watering. The increased mucus may also blur vision.
How is the diagnosis made?
Diagnosis of dry eye is confirmed by a Schirmer Test, in which a narrow strip of filter paper is placed in the corner of each eye for a few minutes and then the amount of moisture in the paper is measured.
What is the treatment?
Because there is no permanent cure, the goal of treatment is to add sufficient moisture to your eyes to relieve the symptoms. In most cases, this simply involves using artificial-tears eyedrops several times a day, or even every hour if necessary. A non-medicated, lubricating ointment placed in your eyes at bedtime may relieve the dryness usually felt upon awakening. If symptoms persist, small "pellets" of concentrated artificial tears may be tucked under the lower eyelid once a day. If the dryness is caused by poor closure of your eyelids when you sleep, try using a small piece of tape (hypo-allergenic paper tape is best) to hold them closed. Soft contact lenses can sometimes relieve the symptoms, possibly because of their water-holding properties. But they do not help everyone. In fact, some patients find that contacts seem to make matters worse. If none of these measures helps, it may be necessary to close the puncta (tiny openings in the eyelids that drain tears into the tear ducts and nose), to prevent losing what little moisture you have. The procedure may involve heat cautery, plastic plugs, or suture. Afterward, you still may need to continue using the eye-drops, ointments, or pellets. A new special vitamin A ointment seems promising for relieving dryness, irritation, and light sensitivity while enhancing tear production and visual acuity. It is presently being evaluated.
Living with Dry Eye
If you have dry eye, try to avoid dry environments and use artificial tears or other moisturizing eyedrops as often as you need them. Always carry the drops with you. If, at any time, you think your eye membranes have become infected (the symptoms are increased redness and secretions), call the office for an immediate appointment.