The medical term for dry eye syndrome is keratoconjunctivitis sicca, although some experts prefer “dysfunctional tear syndrome.” Dry eye syndrome is exactly what it sounds like – chronic dry eyes and other symptoms that are caused by inadequate tear production and distribution. This can occur because either the lacrimal glands do not produce enough tears, or because the tear composition is inadequate and as a result, the tears evaporate too quickly on the surface of the eye.
Major Causes: Behavioral and Environmental
There are many possible causes of dry eye syndrome. Oftentimes, people who spend a high percentage of time on their computers will experience eyestrain, irritation, a burning or stinging sensation, a general “tired” eye sensation and, of course, dry eyes.
A major culprit of dry eye syndrome is contact lens wear. Over time, contact lenses can decrease the nerve sensation on your eye’s cornea. They also absorb moisture and may cause an allergic response known as GPC, or giant papillary conjunctivitis.
One possible cause of dry eye syndrome that sounds almost implausible is driving. However, if you spend a lot of time driving long distances, your eyes are intensely focused, which can result in a reduced blink rate. Your eyes are also exposed to either the air conditioning, heating system or wind.
Sports can also affect your eyes. Any sport that increases the wind current against your eyes will result in increased tear evaporation, such as downhill skiing, skating, sailing or biking.
Your environment can also factor in dry eye syndrome. If you live at high altitudes, or in a hot, dry or windy climate, your tear evaporation rate tends to increase. Indoor environments are just as important – remember the air conditioning and heating example in long-distance driving? Pollution also affects your eyes, particularly tobacco smoke, whether secondhand or otherwise.
Diseases and Conditions
Dry eye syndrome can also be caused by allergies or sensitivities. Allergic reactions can cause inflammation to the eye, which can result in both increased evaporation of tears, as well as decreased tear production. Some eye drops intended for allergy sufferers contain preservatives, which can also contribute to inflammation.
Lagophthalmos is a complicated name for a simple condition: the eyelids do not close properly. Sometimes this happens when you’re sleeping. When the eyes are exposed for too long, they become dry.
There are many other medical conditions that can cause dry eye syndrome, including meibomian gland dysfunction (MGD), anterior blepharitis, primary acquired lacrimal gland disease, stroke, conjunctivochalasis, ocular herpes, Sjogren’s syndrome and others.
The Symptoms of Dry Eye Syndrome
Obviously a major symptom of dry eye syndrome is dry eyes. However, there are many other possible symptoms. They include achy or sore eyes, redness, inflammation, irritation, burning or stinging, itching, blurred vision, tired eyes, contact lens discomfort, a scratchy or grainy sensation, or the feeling that there is something “foreign” in your eyes. Other possible symptoms are excessive mucus discharge or watery discharge from the eyes, a sensitivity to light, and the feeling that your eyes are glued shut when you wake up.