Evaporative dry eye

Evaporative dry eye (EDE) is the most common form of dry eye syndrome. Dry eye syndrome is an uncomfortable condition caused by a lack of quality tears. It’s usually caused by a blockage of the oil glands that line the margins of your eyelids. These tiny glands, called meibomian glands, release oil to cover your eye surface and prevent your tears from drying out.

Keep reading to learn more about EDE.

Symptoms of EDE vary in severity. In general, your eyes will feel uncomfortable. The discomfort can include:

  • grittiness, as though there’s sand in your eyes
  • stinging sensation
  • blurred vision
  • inability to tolerate wearing contact lenses
  • sensitivity to light
  • eye fatigue, especially after working on your computer or reading

Your eyes may also have increased redness or your eyelids may appear swollen.

Read more: Why does my eye hurt when I blink? »

Tears are a mixture of water, oil, and mucus. They coat the eye, making the surface smooth and protecting the eye from infection. The proper mixture of tears also helps you see clearly. If your meibomian glands become blocked or inflamed, your tears won’t contain the right amount of oil to keep them from evaporating. That can cause EDE.

The glands may become blocked for many reasons. If you don’t blink frequently enough you may develop an accumulation of debris on the edge of your eyelids, blocking the meibomian glands. Concentrating hard on a computer screen, driving, or reading can decrease how often you blink.

Other possible factors that disrupt the meibomian glands are:

  • skin conditions, such as rosacea, psoriasis, or scalp and face dermatitis
  • wearing contact lenses for an extended period of time
  • medications, such as antihistamines, antidepressants, retinoids, hormone replacement therapy, diuretics, or decongestants
  • some diseases, such as Sjogren’s syndrome, rheumatoid arthritis, diabetes, thyroid condition
  • allergies that affect your eyes
  • vitamin A deficiency, which is rare in industrialized countries
  • some toxins
  • eye injury
  • eye surgery

If EDE is treated early on, the meibomian gland blockages can be reversed. In some cases, the EDE discomfort can be chronic, requiring ongoing treatment of symptoms.

If your eyes are uncomfortable or painful for more than a short time, or if your vision is blurred, you should see a doctor.

Your doctor will ask you questions about your general health and the medications you take. They’ll also give you a comprehensive eye exam. Your doctor may refer you to an ophthalmologist. An ophthalmologist is a doctor who specializes in eye health.

To check for dry eyes, the doctor may perform special tests to measure your tear volume and quality.

  • The Schirmer test measures tear volume. This involves putting strips of blotting paper under your lower eyelids to see how much moisture is produced after five minutes.
  • Dyes in eye drops can be used to help your doctor see the surface of your eyes and measure the rate of evaporation of your tears.
  • A low-power microscope and a strong light source, called a slit-lamp, can be used to allow your doctor to look at the surface of your eye.

Your doctor may run other tests to rule out possible causes of your symptoms.

Treatment will depend on the severity of your symptoms and whether there’s an underlying systemic cause that needs to be treated. For instance, if a medication is contributing to your dry eye, the doctor may suggest an alternative medication. If Sjogren’s syndrome is suspected, the doctor may refer you to a specialist for treatment.

Your doctor may also suggest simple changes, such as using a humidifier to keep more moisture in the air or, if you wear contact lenses, trying a different cleaning system for your lenses.

For moderate blockage to your meibomian glands, the doctor may suggest applying warm compresses to your eyelids twice a day for four minutes each time. They may also recommend an over-the-counter lid scrub. You may have to experiment with different lid scrubs to find one that works well for you. Baby shampoo may be effective, instead of a more expensive scrub.

Your doctor may also advise eye drops or artificial tears to make your eyes more comfortable. There are many types of drops, tears, gels, and ointments, and you may need to experiment to find what works best for you.

If the blockage to your meibomian glands is more severe, other treatments are available:

  • The LipiFlow thermal pulsation system, used in the doctor’s office, may help unblock the meibomian glands. The device gives your lower eyelid a gentle pulsating massage for 12 minutes.
  • Blinking training and exercises can help improve your meibomian gland functioning.
  • Intense pulsed light therapy along with eye massage may provide some symptom relief.
  • You could also take prescription medications, such as topical azithromycin, a liposomal spray, oral tetracycline, doxycycline (Monodox, Vibramycin, Adoxa, Mondoxyne NL, Morgidox, NutriDox, Ocudox), or anti-inflammatory drugs.

If your EDE is left untreated, the pain and discomfort may make it difficult for you to read, drive, or carry out daily activities. It can also result in serious complications. It may increase your risk of eye infections, including blinding infections, because your tears are not adequate to protect the surface of your eyes. Your eyes may become inflamed, or you may have a greater risk of scratching your cornea or damaging your eyesight.

EDE symptoms can be successfully treated in most cases. In mild cases, the problem may clear up after initial treatment. If an underlying condition like Sjogren’s syndrome is causing the problem, that condition should be treated to try and keep the eye symptoms under control. Sometimes symptoms may become chronic, and you may have to use artificial tears, eye scrubs, and medication to keep your eyes comfortable.

Ongoing research into EDE, and dry eye in general, is likely to come up with new ways to treat symptoms and prevent the meibomian glands from being blocked.

Here are somethings you can do to help prevent EDE:

  • Keep up a daily routine of warm eye compresses and lid scrubs even after your symptoms have resolved.
  • Blink regularly to keep your eyes lubricated.
  • Humidify the air at work and at home.
  • Avoid smoking and being around people who smoke.
  • Drink plenty of water to keep hydrated.
  • Wear sunglasses when you’re outside to protect your eyes from sun and wind. The wraparound kind provide maximum protection.

Read more: How does the 20-20-20 rule prevent eye strain? »