An Overview of Corneal Ulcers

A corneal ulcer is an erosion or open sore on the surface of the cornea. The cornea is the transparent area at the front part of the eye that serves as a window through which we see. It also refracts light and offers protection to other parts of the eye. If the cornea becomes inflamed due to infection or injury, an ulcer may develop.

A corneal ulcer is a serious condition that must be treated promptly to avoid lasting vision problems. Although good medicines are available for treatment, corneal ulcers can cause severe loss of vision and even blindness.

Symptoms

Symptoms of a corneal ulcer are usually obvious, especially if the ulcer is deep. Because the cornea is very sensitive, corneal ulcers tend to produce severe pain. Vision is sometimes impaired, and the eye may be tearing and red. It may also hurt to look at bright lights.

If you have any of the following symptoms, you should be checked by an eye doctor right away:

• Redness
• Pain
• Tearing
• Discharge
• White spot on the cornea
• Blurry vision
• Burning
• Itching
• Light sensitivity

Causes

Corneal ulcers are most commonly caused by germs. Although the human eye is well-protected by the eyelid and abundant tears, germs and bacteria may be able to enter the cornea through small abrasions if it is damaged.

Generally, the deeper the corneal ulcer, the more serious the condition becomes. A very deep ulcer can cause scarring on the cornea, blocking light from entering the eye.

Common causes of corneal ulcers include the following:

• Bacteria
• Viruses
• Injury
• Severe allergic disease
• Fungi
• Amoebas
• Inadequate eyelid closure

Risk factors of corneal ulcers include:

• Contact lens wearers
• People with cold sores, chickenpox, or shingles
• People who use steroid eye drops
• People with dry eye syndrome
• People with eyelid disorders that prevent proper functioning of the eyelid
• People who injure or burn their cornea

Diagnosis

Early diagnosis is important in treating corneal ulcers. Your doctor will ask questions to determine the cause of the ulcer.

Your eyes will then need to be examined under a special bio-microscope called a slit lamp. The slit-lamp exam will allow your doctor to see the damage to your cornea and determine if you have a corneal ulcer. A special dye, called fluorescein, will be placed into your eye to light up the area and aid in the diagnosis.

If it is not clear what the exact cause is, your doctor may take a tiny tissue sample, or culture, of the ulcer in order to know how properly treat it. After numbing your eye with special eye drops, cells may be gently scraped from the corneal surface so that they can be tested.

Treatment

Treatment for corneal ulcers needs to be aggressive, as some ulcers lead to vision loss and blindness. Treatment usually involves antibiotics as well as antiviral or antifungal medications.

Steroid eye drops may also be given to reduce inflammation. Some doctors prescribe the topical eye drops to several times per day until the ulcer is completely healed. In severe cases, patients are hospitalized so that the correct treatment is given.

Certain supplements, such as vitamin C, may be prescribed to lessen corneal scarring. If an ulcer not healing normally with typical treatment, an amniotic membrane will be placed on the cornea for seven to 10 days. 

If a severe infection causes permanent scarring, a corneal transplant may be needed to restore vision. In such instances, blindness or the total loss of the eye may occur if treatment is delivered.