The cornea is the clear tissue at the front of the eye. A corneal ulcer is an open sore in the outer layer of the cornea. It is often caused by infection.
Most corneal ulcers are caused by infections:
- Bacterial infections cause corneal ulcers and are common in people who wearcontact lenses.
- Viral infections are also possible causes of corneal ulcers. Such viruses include the herpes simplex virus (the virus that causes cold sores) or the varicella zoster virus (the virus that causes chickenpox and shingles).
- Fungal infections can cause corneal ulcers and may happen if you overuse eye drops that contain steroids.
Corneal ulcers or infections may also be caused by:
- Eyelids that do not close all the way, such as with Bell’s palsy
- Foreign bodies in the eye
- Scratches (abrasions) on the eye surface
- Severely dry eyes
- Severe allergic eye disease
- Various inflammatory disorders
Symptoms of infection or ulcers of the cornea include:
- Blurry or hazy vision
- Eye that appears red or bloodshot
- Itching and discharge
- Sensitivity to light (photophobia)
- Very painful and watery eyes
- White patch on the cornea