Corneal Ulcer

A corneal ulcer is an open sore on your cornea. It’s considered a medical emergency. Infections are the leading cause. Symptoms include a red or bloodshot eye, watering eye, severe eye pain, and pus or other eye discharge. In severe cases or cases with delays in treatment, a corneal ulcer is more likely to cause vision loss and blindness.


A corneal ulcer appears as white, hazy spots on the eye
A corneal ulcer appears as white, hazy spots on the eye. This corneal ulcer is a bacterial infection related to sleeping in contact lenses.

What is a corneal ulcer?

A corneal ulcer is a wound-like sore on your cornea, the clear, dome-shaped tissue layer at the front of your eye. Corneal ulcers can happen for several reasons, but they usually happen because of infections.

Your corneas are like a windshield on a car. They protect the inside of your eyes from the outside world. Damage to your cornea can create imperfections that are more vulnerable to infections and other issues. Having a corneal ulcer is like having a crack or chip in that windshield. Corneal ulcers are a medical emergency. They need immediate care because they can cause permanent eye damage, low vision and even blindness (especially without treatment).


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Symptoms and Causes

What are the symptoms of corneal ulcers?

Corneal ulcer symptoms vary widely. The most common ones include:

What causes corneal ulcers?

Corneal ulcers can happen for many reasons, but they mainly break down into two categories: infectious and noninfectious.

Infectious causes

Infectious causes are conditions that you can catch from or spread to others. There are four subtypes of infectious causes:

  • Bacteria. The most common types of bacteria that infect the cornea are Pseudomonas, Staphylococcus and Streptococcus species. Many of these bacteria are present all around us but cause infections if the cornea has an injury.
  • Viruses. These include common viruses like Herpes simplex viruses (which cause cold sores or genital herpes) and varicella-zoster virus (which causes both chickenpox and shingles).
  • Fungi. These are most likely with eye injuries from plants or soil (like while gardening. The most common fungi that do this include Aspergillus and Candida. Fungal infections are also a more serious concern for people who are immunocompromised (their immune systems are suppressed). Their immune systems can’t fight off infections well, so those fungi can establish themselves more easily.
  • Parasites. Acanthamoeba family parasites are the most common cause of parasitic infection-related corneal ulcers. These parasites are a major risk for people who swim while wearing contacts. That applies to both bodies of water or pools because Acanthamoeba species can survive lower levels of chlorination (like in undertreated swimming pools). They can also live in tap water, which is why you should never use tap water to clean or store your contacts.

Noninfectious causes

These are conditions or circumstances that can cause corneal ulcers without an infection. Examples include:

  • Eye injuries. Burns, scratches (corneal abrasions), cuts (lacerations) and punctures can all lead to ulcers when they don’t heal correctly. They also make your eyes more vulnerable to infections, which can lead to corneal ulcers forming.
  • Exposure. If you can’t close your eyes fully (a condition called lagophthalmos), that leaves your corneas exposed for much longer than they should be. This can lead to corneal surface damage. Your corneas are also vulnerable to exposure damage in very hot or cold conditions.
  • Very dry eyes. This can be because of weather conditions, eye conditions or a combination of the two.
  • Toxic effects. These can be from toxic substances or, more rarely, from medications you’re taking.
  • Immune conditions. Sometimes, eye inflammation happens because your immune system malfunctions. That inflammation can weaken your corneal tissue, making it vulnerable to damage and ulcer formation.


What are the risk factors for this condition?

Anyone can get corneal ulcers, but you have a higher risk if you have:

  • Contact lenses that you wear often or for long periods (especially if you sleep or swim with them still in, or don’t maintain them properly).
  • A current or past herpes simplex virus infection or varicella-zoster virus infection.
  • Dry eyes.
  • Conditions that make it harder or impossible to fully close your eyes (including different types of facial paralysis like Bell’s palsy, or conditions that make your eyes bulge, like Graves’ disease).
  • Steroid-containing medicated eye drops that you’re currently using or recently used.
  • An injury or burn on your cornea.
  • Type 2 diabetes.
  • A history of eye surgery.
  • A history of other eye diseases, especially corneal diseases.

What are the complications of corneal ulcers?

Corneal ulcers can cause the following complications:


Diagnosis and Tests

How are corneal ulcers diagnosed?

To diagnose a corneal ulcer, an eye specialist or another healthcare provider will rely mainly on an eye exam. Unlike a routine exam that checks all parts of your eye health, these exams will be more issue-specific. A key part of the eye exam that they’ll use is the slit lamp exam. It lets your eye specialist get an up-close, detailed look at your corneas.

One particular lab test your provider might do is a swab culture. That involves taking a soft-tipped swab, collecting some of the discharge from your eye and then sending that to a lab for testing. The test results may tell your provider what kind of infection is causing your ulcer. In cases that aren’t responsive to treatment, your provider may recommend taking this a step further and doing a corneal biopsy. That involves taking a sample of your corneal tissue for testing.

Your eye specialist can tell you more about any other tests they recommend. They can also explain how the tests work, why they should help and any side effects you should expect after the tests.

Management and Treatment

How are corneal ulcers treated, and is there a cure?

Corneal ulcers can happen for many reasons, which means there are many ways to treat them. Some treatments are very specific and only work for certain conditions. Other treatments are more general, helping the symptoms that are most likely with corneal ulcers.

Some of the more common treatment options include:

  • Medications. These can include antibiotics for bacterial infection-related ulcers or other similar approaches for viruses, fungi and parasites. Other medications, like corticosteroids, are more general and treat symptoms of corneal ulcers. Your provider may also recommend nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen (Advil® or Motrin®). Your eye specialist can tell you about the medications, the form they come in and more.
  • Scleral lenses or bandage contact lenses. These are wearable items that help protect your eyes from further damage, giving your corneas time to heal.
  • Tarsorrhaphy. This treatment involves keeping your eye shut for longer periods. To do that, your provider can physically suture your eye closed, or they can use medications like onabotulinumtoxinA (Botox®) to temporarily paralyze the muscles that control your eyelids. Keeping your eye shut gives your cornea a more ideal environment for healing.
  • Surgery. In cases where corneal ulcers aren’t healing, you may need surgery. In more severe cases, a corneal transplant might be necessary.

Other treatments may be possible or necessary, depending on your specific circumstances. Your eye specialist is the best source of information about the treatment options available for your specific case. They can also tell you more about the possible side effects or complications from treatment.


Can corneal ulcers be prevented?

Corneal ulcers aren’t 100% preventable, but there are many things you can do to lower your odds of developing them. Some things you can do include:

  • Don’t sleep in contact lenses. Sleeping in contact lenses is the most common cause of serious corneal ulcers.
  • Don’t wear contact lenses beyond their lifespan. The longer you use soft contact lenses, the more likely they are to grow bacteria. Daily contact lenses are the safest.
  • Wash or sanitize your hands frequently. Use soap and water if your hands look or feel dirty. If they don’t look or feel dirty, you can use an alcohol-based hand sanitizer (at least 60% alcohol).
  • Use eye protection. Protecting your eyes from injury is a key way to avoid injury-related ulcers. Make sure you use the right protection for your eyes, too.
  • Never share things that touch your eyes. This goes for any items that touch areas of your face around your eyes. Some common examples include makeup or hygiene items like washcloths or towels. It also includes items for storing things that touch your eyes, like contact lens cases.

Outlook / Prognosis

What’s the outlook for corneal ulcers?

Corneal ulcers can vary widely depending on what causes them. That includes how long they take to heal or how well they should heal. Your eye specialist can tell you more about what you can expect with your specific case.

Some key factors that can impact your outlook are:

  • Size. Larger ulcers usually have a less favorable outlook.
  • Cause. Some causes are very difficult to treat or recover from.
  • Location. Where an ulcer happens on your cornea can affect the outcome.
  • Response to treatment. The outlook is usually better when ulcers respond well to treatment.

How long do corneal ulcers take to heal?

The healing time for corneal ulcers can vary widely, and many factors play a role in this. Your eye specialist is the best person to tell you the likely timeframe for your case, as they can tailor the estimate to the details of your situation.

Living With

How do I take care of myself?

If you have a corneal ulcer, the most important things you can do include:

  • Follow your provider’s instructions on treatment closely. That goes for medications, how you use or protect your eye, etc.
  • See your provider as recommended. Follow-up visits let your provider monitor an ulcer’s healing and adjust treatment if necessary.
  • Call your eye specialist if you have questions. That includes if you have any new symptoms, questions about how to take medications or treatments, or if you notice treatments aren’t effective. You should also talk to your specialist if any side effects from treatment are causing issues. They may have ways to reduce the impact of symptoms or adjust your treatment to stop side effects from happening.

When should I see my healthcare provider/When should I seek care?

Your eye specialist can tell you what symptoms mean you need to call them or seek medical care. That generally includes symptoms like:

  • Symptoms that keep getting worse even with treatment.
  • An increase in sensitivity to light, especially if this is severe enough to make you avoid certain activities or parts of your daily routine.
  • Blurred vision or a decrease in vision.
  • Severe eye pain.
  • A large amount of discharge from your eyes.

What questions should I ask my eye specialist?

You may want to ask your eye specialist the following:

  • What’s causing my corneal ulcer?
  • What treatments do you recommend?
  • What can I do to help my eye heal?
  • What symptoms mean I need to call you?
  • What symptoms mean I need emergency medical attention?
  • What’s the outlook for my specific case, and what can I do to improve my odds of a favorable outcome?

A note from Cleveland Clinic

If you have a corneal ulcer, you might be worried about whether or not it’ll get better and how it could affect your eye health long term. Corneal ulcers are serious, but they’re usually treatable. Your eye specialist can answer these questions and reassure you about what to expect. They can also help you take steps to improve your odds of a better outcome.

Additional Common Questions

Why does wearing contact lenses increase the risk of a corneal ulcer?

Wearing contacts for long period blocks oxygen from reaching your eyes. Also, bacteria on the lens — transferred from your finger when inserting or from non-sterile cleaning solutions — can get trapped under your lens. These factors raise the risk of infection, which can lead to a corneal ulcer.

A contact lens wearer is about 10 times more likely to get a corneal ulcer than someone who doesn’t wear contacts. Someone who sleeps in contact lenses is about 100 times more likely to get an ulcer than someone who doesn’t wear contacts.

What’s the difference between a corneal abrasion and a corneal ulcer?

A corneal abrasion is a scrape or scratch on your cornea. These corneal injuries usually heal on their own

A corneal ulcer is an open sore on your cornea. Infections, dry eye and other conditions cause a corneal ulcer.

What’s the difference between a corneal ulcer and keratitis?

These eye conditions are closely related.

A corneal ulcer is an open wound — a loss of corneal tissue — that’s often the result of an eye infection.

Keratitis is a more general term for a group of disease processes that cause inflammation of your cornea. Eye infection, injury and wearing contact lenses too long — some of the same causes of corneal ulcer — also cause eye inflammation. Keratitis can lead to a corneal ulcer.

Both conditions can lead to vision loss.

A note from Cleveland Clinic

Corneal ulcers are a vision-threatening eye emergency. Even a minor eye injury can lead to a corneal ulcer. If you think you have symptoms of a corneal ulcer, contact your eye care provider right away. They will examine your eye, make the diagnosis and start treatment. If you wear contact lenses, make sure you know how to properly insert, clean and store them. Your eye care team can teach you proper techniques and answer all your other questions.

Medically Reviewed

Last reviewed on 06/24/2024.

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