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The cornea is the clear surface that covers the front of the eye. It directs and focuses light onto the lens of the eye.
When the cornea is inflamed, injured, or infected, a sore can form. The sore is called a corneal ulcer. It is very painful and can make the eye red, hard to open, and sensitive to light. The sore may feel like something is caught in your eye.
Corneal ulcers can be caused by infection. They can also be linked to problems with the immune system. Wearing contact lenses raises your risk for corneal ulcer, especially if you wear them while you sleep.
To see if you have a corneal ulcer, your doctor looks at your eye with dye on it and tests your vision. If your doctor needs to learn what kind of infection to treat, he or she may also take a tiny sample of tissue for testing.
Your doctor may start treating your eye with antibiotic eyedrops or ointment right away. This is because infection with bacteria is a common cause of corneal ulcer. If tests show that you have another kind of infection, your doctor will change your medicine.
A corneal ulcer is serious. Without prompt treatment, you could lose vision in your eye. Be sure to follow your doctor’s care instructions. Your doctor may send you to an eye specialist (ophthalmologist).