Understanding Corneal Ulcer

Cross section of eye showing cornea, pupil, iris, and lens.A corneal ulcer is an open sore on your cornea. In most cases it’s caused by an infection. The cornea is the eye’s outermost layer. It is a clear, strong layer on the front of your eye. It helps protect your eye from dirt and germs. It also helps control how light enters your eye. Infection or injury to your cornea can cause an ulcer to form. Corneal ulcers can happen in people of any age. If not treated, a corneal ulcer can lead to loss of eyesight and even blindness.

What causes a corneal ulcer?

Many things can cause a corneal ulcer. These include:

  • Bacterial infections, such as Staphylococcus

  • Viral infections, such as herpes

  • Fungal infections

  • Parasitic infections

  • Scrapes or burns on the cornea

  • Conditions that dry out the cornea, such as dry eye or Bell’s palsy

  • Autoimmune diseases, such as rheumatoid arthritis

  • Injury to the cornea

  • Ulcers from reduced blood flow, such as from diabetes

  • Allergies causing inflammation of the eyes

  • Vitamin A deficiency (rare in the U.S.)

If you use contact lenses, you are more at risk for a corneal ulcer if you:

  • Wear soft contact lenses

  • Wear extended-wear contact lenses

  • Wear your lenses for longer than recommended

  • Don’t care for your lenses and lens case as told to

  • Put  your contact lenses in water

Symptoms of a corneal ulcer

Symptoms of a corneal ulcer can include:

  • Severe eye pain

  • A feeling of something in your eye

  • Tearing

  • Discharge from your eye

  • Sensitivity to light

  • Blurred vision

  • Eye redness

  • Swelling of your eyelids

  • A white spot on your cornea

Diagnosing a corneal ulcer

You may see an eye doctor (ophthalmologist). He or she will ask about your past health and your symptoms. You will be given an eye exam. Your eyesight will be checked in both eyes. A dye may be put into your eye to help your eye doctor look at your cornea. He or she may use an ophthalmoscope, which uses a light to look into the back of your eye. You may be asked to look into a large tool called a slit-lamp. This lets your eye doctor see your eye in more detail.

Your cornea may be scraped and the sample sent to a lab. This is done to check for infection. If you wear contact lenses, your contact lenses may be sent to the lab too. You may also have blood tests to help find the cause of your corneal ulcer. Your treatment may vary depending on the cause.