Corneal Infections (infectious keratitis)
The cornea is the clear (transparent) tissue at the front of the eye. A corneal ulcer is an erosion or open sore in the outer layer of the cornea. It is often caused by infection.
Corneal ulcers are most commonly caused by an infection with bacteria, viruses, fungi, or a parasite.
- Acanthamoeba keratitis occurs in contact lens users, especially in people who make their own homemade cleaning solutions
- Fungal keratitis can occur after a corneal injury involving plant material, or in people with a suppressed immune system
- Herpes simplex keratitis is a serious viral infection. It may cause repeated attacks that are triggered by stress, exposure to sunlight, or any condition that impairs the immune system
Corneal ulcers or infections may also be caused by:
- Eyelids that do not close all the way, such as with Bell's palsy
- Foreign bodies in the eye
- Scratches (abrasions) on the eye surface
- Severely dry eyes
- Severe allergic eye disease
- Various inflammatory disorders
- Contact lens wear, especially soft contact lenses worn overnight, may cause a corneal ulcer
Symptoms of infection or ulcers of the cornea include:
- Blurry or hazy vision
- Eye that appears red or bloodshot
- Itching and discharge
- Sensitivity to light (photophobia)
- Very painful and watery eyes
- White patch on the cornea
Exams and Tests
- Examination of scrapings from the ulcer
- Examination under the eyelids
- Fluorescein stain of the cornea
- Pupillary reflex response
- Slit-lamp examination
- Tests for dry eye
- Visual acuity
- Blood tests to check for inflammatory disorders may also be needed
Treatment for corneal ulcers and infections depends on the cause. Treatment should be started as soon as possible to prevent scarring of the cornea and long-term complications.
- If the exact cause is not known, patients may be given antibiotic drops that work against many kinds of bacteria.
- Once the exact cause is known, drops that treat bacteria, herpes, other viruses, or a fungus are prescribed. Severe ulcers sometimes require a corneal transplant.
- Corticosteroid eye drops may be used to reduce swelling and inflammation in certain conditions.
Your eye doctor may also recommend that you:
- Avoid eye makeup
- Don't wear contact lenses at all, or don't wear them at night
- Take pain medications
- Wear an eye patch to keep out light and help with symptoms
- Wear protective glasses
Many people recover completely from corneal ulcers or infections, or they have only a minor change in vision. However, a corneal ulcer or infection can cause long-term damage to the cornea and affect vision.
Untreated corneal ulcers and infections may lead to:
- Loss of the eye (rare)
- Severe vision loss
- Scars on the cornea
- Recurrent infection, especially, herpes infection