It is an open sore or epithelial defect with underlying inflammation in the cornea, the transparent structure in the front part of the eye.
The cornea is superimposed on the iris, which is the colored part of the eye and is separated from the iris by the aqueous fluid in the eye’s anterior chamber.
A corneal ulcer will often appear as an opaque or translucent gray to the white area on the usually clear and transparent cornea. Some corneal ulcers may be too small to see without adequate magnification and lighting.
What are the causes of a corneal ulcer?
Infections cause most corneal ulcers. Bacterial infections cause corneal ulcers and are common in contact lens wearers.
Bacteria can directly invade the cornea if the corneal surface has been altered. Some bacteria produce toxins that can cause ulceration of the cornea.
This is seen in peripheral ulcerative keratitis due to staphylococcal bacteria. Viruses that can cause corneal ulcers include the herpes simplex virus (the virus that causes cold sores) and the Varicella virus.
Although these viral diseases usually only cause herpes simplex or herpes zoster keratitis, corneal ulcers may develop.
Fungal infections can cause corneal ulcers and can occur with inadequate care of contact lenses or excessive use of eye drops containing steroids.
Parasites like Acanthamoeba can also cause corneal ulcers.
What are the risk factors for corneal ulcers?
Risk factors for developing corneal ulcers include:
- Having a previous corneal ulcer.
- Not wearing eye protection when using power tools or welding.
- Having dry eyes.
Misuse contact lenses, do not treat a red-eye ( conjunctivitis ), exposure to ultraviolet light (for example, snow blindness), abnormalities of the eyelids or eyelashes, and suppression of the immune system.
What are the symptoms of a corneal ulcer?
A corneal ulcer can cause pain, a foreign body sensation in the eye; there may be tearing and pus, or a thick discharge from the eye. The vision may be blurred if the ulcer is more centered on the cornea.
There may be increased pain when the person looks at the bright lights.
What are the signs of corneal ulcers?
An ophthalmologist (a doctor specializing in the medical and surgical treatment of eye diseases) may notice signs of inflammation (redness) in the eye’s conjunctiva and the anterior eye chamber.
The redness is due to the dilatation of the conjunctival blood vessels. The eyelids may be swollen, and a round white or gray spot on the cornea may be visible to the naked eye if the ulcer is large.
Not all gray spots are ulcers. The ulcer may be central in the cornea or marginal at the outer edge. There may be swelling (edema) of the cornea around the ulcer.
There may be scars from previous corneal ulcers. There may be a single (or multiple ulcers) in the eye, and ulcers may be present in one or both eyes.
Some more severe corneal ulcers are associated with iritis, an inflammatory response within the anterior chamber. If there is severe iritis, an accumulation of inflammatory cells may occur.
If the corneal ulcer is very severe or threatens vision, your ophthalmologist may refer you to another ophthalmologist specializing in corneal diseases.
The presence of a corneal ulcer can be diagnosed by an ophthalmologist (and other medical caregivers) through an eye exam.
The ophthalmologist can detect an ulcer using a special ocular microscope known as a slit lamp.
A drop containing the fluorescein dye can make the ulcer more accessible to see when placed in the eye.
Scrapes of the ulcer can be sent to the laboratory to identify bacteria, fungi, or viruses. Certain bacteria, such as a Pseudomonas species, can cause a corneal ulcer that is rapidly progressive.
What are the treatment options for corneal ulcers?
The treatment is aimed at eradicating the cause of the ulcer. Anti-infective agents directed against the inciting microbial agent will be used in cases of a corneal ulcer due to infection.
These will generally be in the form of drops or ointments placed in the eye. Still, occasionally, especially in specific viral infections, oral medications will also be used.
Occasionally, steroids will be added, but they should only be used after an examination by an eye doctor or by another doctor using a slit lamp because in some situations.
Steroids can hinder healing or aggravate the infection. The subconjunctival injection of antibiotics can be used occasionally.
In cases of patients aggravated by ocular dryness or corneal exposure (for example, corneal exposure to a dry and sandy environment).
Tear substitutes will be used, possibly accompanied by patches or bandage contact lenses. The driving agent must be removed from the eye in corneal ulcers involving lesions.
I am using abundant irrigation for chemicals or a microscope with a slit lamp to remove particles such as wood or metal.