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.

See also: Corneal injury

Bacterial keratitis; Fungal keratitis; Acanthamoeba keratitis; Herpes simplex keratitis

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, esposure 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.

Images

Eye

Corneal injury

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Corneal ulcers and infections Symptoms

Review Date: 07/28/2010
Reviewed By: Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine; and Franklin W. Lusby, MD, Ophthalmologist, Lusby Vision Institute, La Jolla, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)