Eye Diseases What is a Corneal Ulcer?

A corneal ulcer is an open infected sore on the cornea. It is a very serious eye problem. This infection cause inflammation of the cornea, a condition called keratitis. Tissue loss because of inflammation produces an ulcer. The ulcer can either be centrally located, thus greatly affecting vision, or peripherally located.




What Causes Corneal Ulcer?

The most common cause of corneal ulcers are germs like Bacteria, Fungi, Virus and Protozoa. But most of these germs cannot invade a healthy cornea with adequate tears and a functioning eyelid. They gain access because injury, which can be as trivial as a scratch on the cornea, has impaired these defense mechanisms. A direct injury from a foreign object inoculates germs directly through the outer layer of the cornea, just as it does to the skin. A caustic chemical can inflame the cornea by itself or so damage it that germs can invade. Improper use of contact lenses has become a common cause of corneal injury. Eyelid or tear function failure is the other way to make the eye vulnerable to infection. Tears and the eyelid together wash the eye and prevent foreign material from settling in. Tears contain enzymes and other substances to help protect against infection. Certain diseases dry up tear production, leaving the cornea dry and defenseless. Other diseases paralyze or weaken the eyelids so that they cannot effectively protect and cleanse the eyes.

What are the Signs and Symptoms of a Corneal Ulcer?

The eye becomes intensely sensitive, so corneal ulcers normally produce severe pain. If the corneal ulcer is centrally located, vision is impaired or completely absent. Tearing is present and the eye is red. It hurts to look at bright lights. The white of your eye may be red and you may have clear, yellow, or green-colored fluid coming from your eye.


How is a Corneal Ulcer Treated?

Your doctor will take a case history to try to determine the cause of the ulcer. This can include improper use of contact lenses; injury, such as a scratch from a twig; or severe dry eye. An instrument called a slit lamp will be used to examine the cornea. The slit lamp is a microscope with a light source that magnifies the cornea, allowing the extent of the ulcer to be seen. Fluorescein, a yellow dye, may be used to illuminate further detail.

To try and find out if a germ is responsible for the ulcer and its identification, your eye specialist may recommend Corneal Scraping samples to be taken directly from the infected part of the cornea and sending them to the laboratory for analysis.

A corneal ulcer needs to be treated aggressively, as it can result in loss of vision or the eye. The first step is to eliminate infection. Broad spectrum anti-microbials will be used before the lab results come back. Medications may then be changed to specifically target the cause of the infection. A combination of medications may be necessary. Patients should return for frequent follow-up visits so that the doctor can monitor the healing process. The cornea can heal from many insults, but if it remains scarred, corneal transplantation may be necessary to restore vision.

What are the Risks in a Corneal Ulcer?

Treated aggressively and early enough, corneal infections will usually resolve. However, left untreated, infections can lead to spread of the corneal ulcer, corneal scarring or perforation of the cornea. In certain cases there may be a risk of the infection going inside the eye. Other problems like Glaucoma may also occur. Patients with certain systemic diseases that impede healing (such as diabetes mellitus or rheumatoid arthritis) may need more aggressive treatment. The later the treatment, the more damage will be done and the more scarring will result. Corneal Transplant (LINK) (Therapeutic Keratoplasty) may be performed as an eye saving measure in case of non-healing ulcers, progressive ulcers, impending perforations and frank perforation.