A corneal ulcer is an open sore on the cornea of the eye. It’s usually due to an infection affecting the clear front surface of the eye, resulting in inflammation of the cornea (keratitis). A corneal ulcer typically causes a painful red eye, with mild to severe eye discharge and reduced vision. Medical treatment is required. Corneal ulcers are most commonly due to infection by bacteria, viruses, fungi, or amoebas.
Viral infections such as the herpes simplex virus(which causes cold sores) or the varicella virus (which causes chickenpox and shingles)
Fungal infections such as Fusarium, Aspergillus, or Candida, possibly after an injury by something natural like a branch or twig. These infections are rare.
Parasitic infections with Acanthamoeba, an amoeba found in fresh water and dirt
Noninfectious causes— all of which may be complicated by infection—include neurotrophic keratitis (resulting from loss of corneal sensation), exposure keratitis (due to inadequate lid closure), severe dry eye, severe allergic eye disease, and various inflammatory disorders that may be purely ocular or part of a systemic vasculitis.
Contact lens wearers are particularly susceptible to eye irritation that can lead to a corneal ulcer. A contact lens may rub against the eye’s surface, creating slight damage to the epithelium that may enable bacteria to penetrate the eye.
If you are a contact lens wearer, you can increase your chances of avoiding a corneal ulcer by practicing good hygiene such as washing your hands before handling lenses and following other safety tips.
Delayed or ineffective treatment of corneal ulceration may lead to devastating consequences with corneal scarring or intraocular infection. Prompt referral is essential. Patients complain of pain, photophobia, tearing, and reduced vision. The eye is red, with predominantly circumcorneal injection, and there may be purulent or watery discharge. The corneal appearance varies according to the underlying cause.
Corneal Ulcer Symptoms
Symptoms of corneal ulcers include:
- redness of the eye
- severe pain and soreness of the eye
- the feeling of having something in your eye
- pus or other discharge
- blurred vision
- sensitivity to light
- swelling of the eyelids
- a white spot on your cornea that you may or may not be able to see when looking in the mirror
Corneal ulcers can badly and permanently damage your vision and even cause blindness if they are not treated.
Corneal Ulcer Diagnosis
Your ophthalmologist will use a special dye called fluorescein (pronounced FLOR-uh-seen) to light up any damage to your cornea. They will then examine your cornea using a special microscope called a slit lamp. The slit-lamp exam will allow your ophthalmologist to see the damage to your cornea and determine if you have a corneal ulcer.
If your ophthalmologist thinks that an infection has caused your corneal ulcer, they may take a tiny tissue sample. Examination of this sample helps identify and properly treat the infection.
Treatment aims to eradicate the cause of the ulcer. Physicians will use anti-infective agents directed at the inciting microbial agent in cases of corneal ulcer due to infection. Generally, these will be in the form of eye drops or ointments that the patient will place in the eye. Occasionally, especially in certain viral infections, doctors will also prescribe oral medications. In certain situations, medical professionals will prescribe corticosteroid eye drops, but people should only use them after examination by an eye doctor or other physician using a slit lamp, because in some situations, steroids may hinder healing or aggravate the infection. Physicians may occasionally utilize subconjunctival injection of antibiotics.
In cases of patients aggravated by eye dryness or corneal exposure (for example, corneal exposure to a dry and/or sandy environment), tear substitutes will be used, possibly accompanied by patching or a bandage contact lens.
In corneal ulcers involving injury, the inciting agent must be removed from the eye (using copious irrigation for chemicals or by using a slit lamp microscope to remove particles such as wood or metal) and then adding medications to prevent infection and minimize scarring of the cornea.
If the corneal ulcer is due to an eyelash growing inward, the offending lash should be removed, together with its root. If it grows back in an abnormal manner, the root may have to be destroyed using a low-voltage electrical current. If the corneal ulcer is secondary to the eyelid turning inward, surgery directed at correctly repositioning the eyelid may be necessary.
Contact lenses should be discontinued in the affected eye of any case of corneal ulcer, regardless of whether the ulcer was initially caused by the contact lens.
If the ulcer cannot be controlled with medications, it may be necessary to surgically debride the ulcer. If the ulcer causes significant corneal thinning and threatens to perforate the cornea, a surgical procedure known as a corneal transplant (keratoplasty) may be necessary.
Individuals with corneal ulcers due to immunological diseases require patient-specific treatment with immunosuppressive drugs. Such patients may require the ophthalmologist to coordinate in conjunction with other doctors. In patients with secondary iritis associated with a corneal ulcer, cycloplegic eye drops may be used to decrease pain and dilate the pupil.
Anyone with an irritated eye that does not improve quickly after removing a contact lens or after mild irrigation should contact an ophthalmologist immediately. Do not borrow someone else’s eye drops.