Diseases & Condition--Dry Eyes Syndrome

What is a Dry Eye

Decreases Tear Production

Dry eyes is a common condition that occurs when your tears aren't able to provide adequate lubrication for your eyes. Tears can be inadequate for many reasons. For example, dry eyes may occur if you don't produce enough tears or if you produce poor-quality tears.

Dry eyes feel uncomfortable. If you have dry eyes, your eyes may sting or burn. You may experience dry eyes in certain situations, such as on an airplane, in an air-conditioned room, while riding a bike or after looking at a computer screen for a few hours.

Treatments for dry eyes may make you more comfortable. These treatments can include lifestyle changes and eye drops. You'll likely need to take these measures indefinitely to control the symptoms of dry eyes.

Symptoms of Dry Eyes

Signs and symptoms, which usually affect both eyes, may include:

• A stinging, burning or scratchy sensation in your eyes
• Stringy mucus in or around your eyes
• Sensitivity to light
• Eye redness
• A sensation of having something in your eyes
• Difficulty wearing contact lenses
• Difficulty with nighttime driving
• Watery eyes, which is the body's response to the irritation of dry eyes
• Blurred vision or eye fatigue

Causes of Dry Eye

Dry eyes are caused by a lack of adequate tears. Your tears are a complex mixture of water, fatty oils and mucus. This mixture helps make the surface of your eyes smooth and clear, and it helps protect your eyes from infection.

For some people, the cause of dry eyes is decreased tear production. For others it's increased tear evaporation and an imbalance in the makeup of your tears.

Decreased tear production

Dry eyes can occur when you're unable to produce enough tears. The medical term for this condition is keratoconjunctivitis sicca(ker-uh-toe-kun-junk-tih-VY-tis SIK-uh). Common causes of decreased tear production include:

• Aging
• Certain medical conditions, including diabetes, rheumatoid arthritis, lupus, scleroderma, Sjogren's syndrome, thyroid disorders and vitamin A deficiency
• Certain medications, including antihistamines, decongestants, hormone replacement therapy, antidepressants, and drugs for high blood pressure, acne, birth control and Parkinson's disease
• Laser eye surgery, though symptoms of dry eyes related to this procedure are usually temporary
• Tear gland damage from inflammation or radiation

Increased tear evaporation

Common causes of increased tear evaporation include:

• Wind, smoke or dry air
• Blinking less often, which tends to occur when you're concentrating, for example, while reading, driving or working at a computer
• Eyelid problems, such as out-turning of the lids (ectropion) and in-turning of the lids (entropion)

Imbalance in tear composition

The tear film has three basic layers: oil, water and mucus. Problems with any of these layers can cause dry eyes. For example, the oil film produced by small glands on the edge of your eyelids (meibomian glands) might become clogged. Blocked meibomian glands are more common in people with inflammation along the edge of their eyelids (blepharitis), rosacea or other skin disorders.

Treatments and drugs

For most people with occasional or mild dry eye symptoms, it's enough to regularly use over-the-counter eyedrops (artificial tears). If your symptoms are persistent and more serious, you have other options. What you do depends on what's causing your dry eyes.

Some treatments focus on reversing or managing a condition or factor that's causing your dry eyes. Other treatments can improve your tear quality or stop your tears from quickly draining away from your eyes.

Treating the underlying cause of dry eyes

In some cases, treating an underlying health issue can help clear up the signs and symptoms of dry eyes. For instance, if a medication is causing your dry eyes, your doctor may recommend a different medication that doesn't cause that side effect. If you have an eyelid condition, such as out-turning lids (ectropion), your doctor may refer you to an eye surgeon who specializes in plastic surgery of the eyelids (oculoplastic surgeon). Or if you have rheumatoid arthritis, your doctor may refer you to a rheumatologist.

Medications

Prescription medications used to treat dry eyes include:

• Drugs to reduce eyelid inflammation. Inflammation along the edge of your eyelids can keep oil glands from secreting oil into your tears. Your doctor may recommend antibiotics to reduce inflammation. Antibiotics for dry eyes are usually taken by mouth, though some are used as eyedrops or ointments.
• Eyedrops to control cornea inflammation. Inflammation on the surface of your eyes (cornea) may be controlled with prescription eyedrops that contain the immune-suppressing medication cyclosporine (Restasis) or corticosteroids. Corticosteroids are not ideal for long-term use due to possible side effects.
• Eye inserts that work like artificial tears. If you have moderate to severe dry eye symptoms and artificial tears don't help, another option may be a tiny eye insert that looks like a clear grain of rice. Once a day, you place the hydroxypropyl cellulose (Lacrisert) insert between your lower eyelid and your eyeball. The insert dissolves slowly, releasing a substance that's used in eyedrops to lubricate your eye.
• Tear-stimulating drugs. Drugs called cholinergics (pilocarpine, cevimeline) help increase tear production. These drugs are available as pills, gel or eyedrops. Possible side effects include sweating.
• Eyedrops made from your own blood. These are called autologous blood serum drops. They may be an option if you have severe dry eye symptoms that don't respond to any other treatment. To make these eyedrops, a sample of your blood is processed to remove the red blood cells and then mixed with a salt solution.

Other procedures

Other procedures that may be used to treat dry eyes include:

• Closing your tear ducts to reduce tear loss. Your doctor may suggest this treatment to keep your tears from leaving your eye too quickly. This can be done by partially or completely closing your tear ducts, which normally serve to drain tears away.
  Tear ducts can be plugged with tiny silicone plugs (punctal plugs). These are removable. Or tear ducts can be plugged with a procedure that uses heat. This is a more permanent solution called thermal cautery.
• Using special contact lenses. Ask your doctor about newer contact lenses designed to help people with dry eyes.
  Some people with severe dry eyes may opt for special contact lenses that protect the surface of your eyes and trap moisture. These are called scleral lenses or bandage lenses.
• Unblocking oil glands. Dry eyes caused by blocked oil glands may be helped by a treatment called LipiFlow thermal pulsation. During the treatment, a device that looks like an eyecup is placed over your eye. It delivers a gentle, warm massage to the lower eyelid. The procedure takes less than 15 minutes. It's not clear whether this method is better at clearing blocked oil glands than regular warm compresses and eyelid washing.
• Using light therapy and eyelid massage. A technique called intense-pulsed light therapy followed by massage of the eyelids helps people with severe dry eyes. In one study, the therapy was given monthly to 78 people, and 68 of them experienced reduced symptoms.

Prevention of Dry Eye

Avoid air blowing in your eyes. Don't direct hair dryers, car heaters, air conditioners or fans toward your eyes.

Add moisture to the air. In winter, a humidifier can add moisture to dry indoor air.

Consider wearing wraparound sunglasses or other protective eyewear. Safety shields can be added to the tops and sides of eyeglasses to block wind and dry air. Ask about shields where you buy your eyeglasses.

Take eye breaks during long tasks. If you're reading or doing another task that requires visual concentration, take periodic eye breaks. Close your eyes for a few minutes. Or blink repeatedly for a few seconds to help spread your tears evenly over your eyes.

Be aware of your environment. The air at high altitudes, in desert areas and in airplanes can be extremely dry. When spending time in such an environment, it may be helpful to frequently close your eyes for a few minutes at a time to minimize evaporation of your tears.

Position your computer screen below eye level. If your computer screen is above eye level, you'll open your eyes wider to view the screen. Position your computer screen below eye level so that you won't open your eyes as wide. This may help slow the evaporation of your tears between eye blinks.

Stop smoking and avoid smoke. If you smoke, ask your doctor for help devising a quit-smoking strategy that's most likely to work for you. If you don't smoke, stay away from people who do. Smoke can worsen dry eyes symptoms.

Use artificial tears regularly. If you have chronic dry eyes, use eyedrops even when your eyes feel fine to keep them well-lubricated.