The most common cause of a corneal ulcer is infection. Tiny particles of sand, dirt, or metal can scratch the cornea. These scratches are then invaded by bacteria, which ultimately leads to ulceration.
If you’re suffering from dry eyes, you are more susceptible to ulcers. Tears help to clean the eye and prevent germs from spreading. When the eye does not produce enough tears, bacteria is able to thrive.
Disorders such as Bell’s palsy, which prevents the eye or eyes from closing properly, can also cause the eye to dry out. Affecting the muscles, these conditions sometimes cause the eyelid to turn inwards. This can lead to the eyelid rubbing against the cornea, causing abrasions.
If you are suffering from a fungal infection, you may already be treating it with steroid eye drops. But the overuse of these can increase the chance of the eye becoming infected. To prevent this, use steroid eye drop exactly as prescribed and see your eye specialist of you have any concerns.
Viral infections, such as the herpes simplex virus (the cause of cold sores), can affect the eye and nose. If this happens, there is the possibility of an ulcer forming.
Although they can affect both adults and children, corneal ulcers occur more often in contact lens wearers. And wearing extended-wear lenses–those that are kept in for several days or overnight–increases this chance even more.
Always follow the hygiene advice for cleaning contact lenses. If bacteria get on the underside of the lens, they will multiply and damage the cornea. Any dirt or slight defect on the lens can also scratch the cornea causing infection.