Dr. Mack: Expert on Dry Eyes

Dry Eye: Tears are a important part of a healthy  eye.

Without an adequate film of tears on our eyes, sharp vision is not possible!

The tear film actually consist of three layers.

  1. An oily layer forms the outer most surface of the tear film, smoothing the tear surface and reducing evaporation of the tears.
  2. A watery middle layer cleanses the eye and washes away foreign particles or irritants.
  3. An inner layer of mucus allows the watery layer to spread evenly over the surface of the eye and helps the eye remain moist.

For our eyes to be healthy we need not only the correct quantity of tears, but the correct quality as well. If there’s an imperfection in anyone of the tear film layers, then the quality of tears can be affected.

The eye has two different ways to make tears.

It can make tears at a slow and steady rate to keep the eye moist and comfortable or it can also make large quantities of tears in response to eye irritation or emotion. Sometimes our eyes do not make enough tears but at other times the quality of the tears is not good enough to keep our eyes healthy and comfortable. These common occurences leads to a condition called DRY EYE. Sometimes with this condition, the dryness irritates the eye and excessive tearing may occur. This is because the eye is over compensating for dryness by producing too much of the watery portion of the tear film. However the oily and mucus portions of the tear film may also be deficient which can actually cause the dryness. Many people are perplexed when their doctor tells them that they have dry eyes. What they see and feel is excessive tearing. The problem is not that they aren’t enough tears but that they don’t have the correct quality of tears. For some people, dry eye can be a short-term problem brought on by an environmental factor such as smoke or wind. For others, in could be a chronic long-term problem, requiring effective treatment so that vision or comfort is not affected.

Symptoms of dry eye include:

  • Excessive tearing
  • Stinging or burning eyes
  • Itching
  • Scratchiness
  • Stringy mucus in or around the eyes
  • Excessive eye irritation from smoke or wind
  • Difficulty wearing contact lenses
  • Brief or ongoing blurring of vision that may change with each blink

Chronic dry eyes can be caused by a number of things.

Age is one common factor since tear productions normally decreases as we age. Other dry eye can occur in both men and women at any age. Women are most often affected, especially after menopause. Another common cause of dry eye symptoms is the use of prescription and over the counter medications such as:

  • Diurectics (for fluid retention or high blood pressure)
  • Beta-blockers (for high blood pressure or heart disease)
  • Antihistamines
  • Sleeping pills
  • Anxiety medications
  • Pain relievers

Certain medical conditions such as auto-immune diseases may also cause dry eyes and dry mouth.

One common auto-immune condition is called Sjogren’s syndrom. Other culprits of dry eye symptoms may include blepharitis or rosacea. Eyelid problems that affects the outer oily layer of the tear film causing natural tears to evaporate too quickly from the eye. Other more rare diseases may also affect the inner mucus layer of the tear film, preventing the natural tear film from staying on the eye.

Your ophthalmologist is usually able to tell if you have dry eye by examining your eyes.

Sometimes test that measure tear production are necessary. One test called the Schirmer tear test involves placing filter paper strips under the lower eyelids to measure the rate of tear production under various conditions. Another test uses a diagnostic eye drop to look for certain patterns of dryness on the surface of the eye.

Treating dry eye is generally accomplished by three methods

  1. Adding tears
  2. Conserving tears
  3. And preventing tear evaporation

To add tears, eye drops called artificial tears are used. Similar to you own natural tears, these drops lubricate the eyes and help maintain moisture. Artificial tears are available without prescription and you can use them as often as you need them. Once or twice a day or even several times an hour. There are many brands on the market so you may want to try a few of them so find the one you like best. Some people may be sensitive to the preservatives in artificial tears. So, preservative free eye drops are available. Also if you need to use artificial tears more than every two to four hours, preservative free brands may better for you.

Your ophthalmologist may choose to prescribe an eye drop medication containing a anti inflammatory such as cyclosporine. This medication helps to restore not only the right quantity of tears but also the correct quality of the different tear films.

Saving your eyes own tears is another approach to keeping the eyes moist.

Tears drain out of the eye thru a tiny opening of the tear ducts on the eyelid margin called Puncta­. Then to a small channel into the nose. This is why your nose runs when you cry. Your ophthalmologist may recommend closing off the puncta temporarily or permanently using tiny punctal plugs. Punctal plugs can be inserted in a lower eyelid, in upper eyelid or in both eyelids. Using punctal plugs saves your own tears from draining away and help artificial tears last longer.

Tears evaporate like any other liquid, but you can take steps to limit that evaporation.

First, a person with dry eyes should stay away from anything that cause this dryness, like very warm rooms, hair dryer, wind and smoking. When the indoor heat is on, use a humidifier to add more moisture to dry air. When you are exposed to the elements, such as wind and sun light, wear wrap around glasses  to reduce the drying effect from the wind and light. Some people with dry eyes complain that their eye feel scratchy when they wake up. This symptom can be treated by using an artificial tear ointment or gel eye drops at bed time. Finally, for some people with blepharitis or rosacea, your ophthalmologist may also prescribe an antibiotic ointment, warm eyelids compresses and/or lid hygiene to relieve your symptoms.

Dry eye is a common and uncomfortable condition. Talk with your ophthalmologist about treatment options.