The cornea is a thin, clear, spherical layer of tissue on the surface of the eye that provides a window for light to pass through. In a healthy eye, the cornea bends or refracts light rays so they focus precisely on the retina in the back of the eye.
There are many diseases that can affect the cornea, causing pain or loss of vision. Disease, infection or injury can cause the cornea to swell (called “edema”) or degrade (become cloudy and reduce vision). Common diseases and disorders that affect the cornea include:
- Bullous Keratopathy
- Conjunctivitis (“Pink Eye”)
- Dry Eye
- Corneal Dystrophies including Fuchs’ Dystrophy and Lattice Dystrophy
- Glaucoma (High Eye Pressure)
- Keratitis (Viral Inflammation)
- Ocular Herpes
- Shingles (Herpes Zoster)
- Stevens-Johnson Syndrome
Treatment for corneal disease can take many forms, depending on the underlying problem as well as the patient’s preferences. Some conditions resolve on their own and many can be treated with medication. If the cornea is severely damaged or if there is a risk of blindness, a corneal transplant may be recommended to preserve vision.
Learn more about the cornea and corneal disease from the National Eye Institute.