Infections
Most corneal ulcers are caused by infections resulting from bacteria, viruses or fungi.- Bacterial Infections: Tiny tears or scratches on the cornea can make it easier for bacteria to enter the eye and cause an infection. Contact lens wearers have additional infection risks. Bacterial infections can arise if they do not properly handle and clean their lenses, as bacteria may get trapped underneath the lens. Over-wearing a contact lens can create an environment favorable for harmful bacteria to grow, too.
- Viral Infections: Certain viruses, such as herpes simplex and varicella, can lead to corneal ulcers (viral keratitis). These viruses can cause damage to the many layers of the surface of the eye.
- Fungal Infections: Infections caused by certain fungi can lead to corneal ulcers. Often referred to as fungal keratitis, these infections cause deep and severe corneal ulcers. Contact lens wearers may develop these infections by improperly caring for their contact lenses. A fungal infection can also occur after a corneal injury involving plant material.
Another organism thought to cause corneal ulcers is a parasite called Acanthamoeba. Acanthamoebic keratitis can cause severe corneal ulcers that often cause severe vision loss if not diagnosed very early. Wearing contact lenses while swimming or using a hot tub is an activity common among people who contract this parasite. Although acanthameoba is present in higher quantities in fresh water, such as lakes and rivers, it can also be found in pools, hut tubs and drinking water systems.
Other Causes of Corneal Ulcer
Some corneal ulcers are caused by certain underlying conditions and disorders. People with severe dry eye syndrome can develop corneal ulcers, as natural tears provide a layer of protection against germs. If the surface of the eye becomes very dry, it may also become raw and develop an ulcer. People whose eyes fail to shut completely, such as those suffering from Bell's palsy, may also develop corneal ulcers. Corneal ulcers have also been known to be caused by severe allergies or certain auto-immune diseases such as rheumatoid arthritis, lupus or psoriasis.What You Should Know About Corneal Ulcers
Minor injuries to your eye can lead to corneal ulcers. Some corneal ulcers can be devastating to your eyes and vision. If you think you may have a corneal ulcer, see your eye doctor immediately. Prompt treatment may prevent significant vision loss or even the loss of an eye.Source:
Catania, Louis J. "Primary Care of the Anterior Segment." Second Edition, Copyright 1995.
