A corneal ulcer is an open lesion that appears on the eye. Ulcers can be caused by viral, bacterial, or fungal infections and often result in eye pain and pus discharge. Without prompt medical treatment, a corneal ulcer can permanently damage a person's vision. It is important to visit the emergency room or an ophthalmologist as soon as possible to receive a proper diagnosis and learn which medications can help relieve symptoms and promote healing. Doctors can also provide helpful information on how to prevent future eye infections.
A person can experience a corneal ulcer if the outer layer of the eye, called the cornea, is injured. A scrape or puncture on the cornea leaves the eye susceptible to bacterial infections. People who wear contact lenses are at a higher risk of developing ulcers because a lens can irritate the eye and trap bacteria in the cornea. An ulcer can also be the result of a viral infection, such as the herpes simplex virus, or a fungus. Less commonly, a vitamin A deficiency can weaken the cornea and render the immune system less effective at fighting off bacteria.
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The most common symptoms of a corneal ulcer include redness, excessive tear production, and constant pain. An an infection worsens, the lower eyelid can become swollen and a milky pus can build up and discharge from the eye. Vision often becomes blurry, and a person might develop headaches and feelings of nausea. An ulcer that is left untreated can actually scar the cornea and cause permanent vision loss.
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A person who believes that he or she might have a corneal ulcer should seek medical attention immediately. Upon initial inspection at an emergency room or ophthalmologist's office, a doctor uses a specialized microscope to carefully examine the ulcer. If it is unclear what caused a lesion, the doctor collects a tissue sample for laboratory analysis. Lab tests can reveal the presence of bacteria, viruses, or fungi and help the physician determine the proper course of treatment.
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Corneal ulcers are usually easy to treat with eye drops and oral medications that contain antiviral, antibacterial, or antifungal agents. By applying drops daily and avoiding overexposure to bright light, an ulcer usually heals in less than three weeks. A patient who wears contacts might be instructed to wear glasses instead during the healing phase. In addition, a physician can explain the importance of removing contacts at bedtime and proper lens cleaning procedures to help reduce the risk of recurring eye ulcers.