Corneal Ulcer (Corneal Infection)
What Is a Corneal Ulcer?
Your cornea is the clear, dome-shaped window at the front of your eye. It helps focus light so you can see clearly. When the outer layer of the cornea is damaged, germs can enter and cause an infection that creates an ulcer.
Even a tiny scratch or injury can give bacteria, viruses, fungi, or parasites a way to invade the tissue. Once inside, the infection breaks down healthy corneal cells and forms a painful open sore that can threaten your vision.
Bacterial infections are the most common cause of corneal ulcers, especially in contact lens wearers. Fungal ulcers often develop after an eye injury involving plant material, such as a branch scratch. Viral ulcers are usually linked to the herpes simplex virus or herpes zoster, which can affect the cornea in different patterns. Parasitic ulcers, though rare, are most commonly caused by Acanthamoeba, a microscopic organism typically seen when contact lenses are exposed to contaminated water, including tap water, well water, or swimming pools.
Acanthamoeba keratitis can be challenging to diagnose and requires prolonged specialized treatment that differs from bacterial or viral infections. Viral keratitis also has different forms, and management depends on whether the virus affects the surface layer or deeper structures. It is critical never to use steroid eye drops on your own, as steroids can severely worsen certain infections, particularly active viral infections.
Each type of infection requires a different treatment approach, which is why we work quickly to identify the specific organism causing your ulcer.
A corneal ulcer is always a serious condition that demands immediate attention. Without prompt treatment, the infection can spread deeper into your eye and cause permanent scarring on the cornea. Severe cases may lead to vision loss or even loss of the eye itself.
The good news is that most corneal ulcers respond well to treatment when we catch them early. Our goal is to stop the infection, promote healing, and preserve as much of your vision as possible.
Signs and Symptoms of a Corneal Ulcer
Most people with a corneal ulcer experience significant eye pain that ranges from a gritty, foreign-body sensation to intense throbbing. This pain often gets worse when you blink or when light hits your eye.
- Sharp or burning pain in the affected eye
- Feeling like something is stuck in your eye
- Extreme sensitivity to light, making it hard to keep your eye open
- Pain that does not improve with over-the-counter eye drops
- Severe pain that seems out of proportion to the visible redness, which can be a clue to certain infections such as Acanthamoeba
Your eye will likely appear red or bloodshot as blood vessels swell in response to the infection. You may also notice excessive tearing as your eye tries to flush out the irritant.
Discharge is another common sign and can vary depending on the type of infection. Bacterial ulcers can produce thick, yellow or green pus, though discharge patterns vary and some bacterial infections cause less obvious drainage. Viral infections may cause watery discharge. The absence of heavy discharge does not rule out a serious corneal infection. Any unusual drainage, excessive tearing, or persistent redness should prompt a call to our office.
Blurred or decreased vision often develops as the infection damages the clear corneal tissue. You may have trouble seeing details or notice that your vision seems cloudy or hazy.
In many cases, a corneal ulcer creates a visible white or gray spot on the surface of the eye. This spot is the ulcer itself and may be small or large depending on the severity of the infection. Sometimes the spot is only visible under magnification during an exam.
Any combination of eye pain, redness, and vision changes should be treated as urgent. Do not wait to see if symptoms improve on their own. Contact our office immediately or visit an emergency eye care center if you notice any of these red flags:
- You are a contact lens wearer with eye pain, redness, or light sensitivity
- Decreased or blurred vision in the affected eye
- A white or cloudy spot visible on your cornea
- Recent eye injury involving plant material, soil, or organic matter
- Severe photophobia or inability to keep your eye open
Prompt care is essential because untreated infections can advance quickly, making treatment more difficult and increasing the risk of permanent damage.
What Puts You at Risk for a Corneal Ulcer?
Wearing contact lenses is the leading risk factor for corneal ulcers in otherwise healthy people. Lenses can trap bacteria against your cornea, especially if you wear them longer than recommended, sleep in them, or fail to clean them properly.
- Sleeping in contact lenses increases infection risk significantly
- Using tap water or saliva to rinse lenses introduces harmful organisms
- Showering, swimming, or using hot tubs while wearing lenses
- Topping off old solution instead of emptying and refilling your case with fresh solution daily
- Wearing old or damaged lenses creates tiny scratches that invite infection
- Not replacing your lens case regularly allows bacteria to build up
- Certain lens types, such as orthokeratology or extended wear lenses, may carry higher risk
Any trauma to the eye can break the protective barrier of the cornea. Scratches from fingernails, tree branches, or debris can provide an entry point for germs. Even a small abrasion can develop into an ulcer if bacteria or fungi get into the wound.
We often see corneal ulcers after workplace injuries, sports accidents, or yard work incidents. Wearing protective eyewear during these activities can prevent many of these injuries.
Healthy tears contain natural defenses that wash away germs and keep your cornea moist. When your eyes do not produce enough tears or the tears evaporate too quickly, your cornea becomes vulnerable to infection and injury.
Chronic dry eye conditions, eyelid problems that prevent complete blinking, and certain medications can all reduce your tear protection. We may recommend treatments to improve your tear film if dry eyes are increasing your ulcer risk.
If your immune system is compromised by diabetes, HIV, cancer treatment, or immunosuppressive medications, your body has a harder time fighting off infections. People with weakened immunity are more prone to unusual or severe corneal infections, including fungal and parasitic ulcers.
Using steroid eye drops without close medical supervision also increases your risk. Steroids can suppress your eye's natural defenses and allow infections to take hold or worsen rapidly. Conditions that affect eyelid closure, such as Bell palsy or thyroid eye disease, also raise your risk because your cornea may not stay properly protected and lubricated.
How We Diagnose a Corneal Ulcer
We begin by asking about your symptoms, medical history, and any recent eye injuries or contact lens use. Then we perform a detailed examination of your eye using specialized equipment.
You will sit at a slit lamp, a microscope with a bright light that lets us see the structures of your eye in high magnification. This exam allows us to identify the ulcer, evaluate its size and depth, and check for signs of spreading infection.
We typically use a special orange dye called fluorescein to make the ulcer easier to see. We place a small drop in your eye, and the dye temporarily stains damaged areas of the cornea bright green under blue light.
- The staining pattern helps us determine the ulcer location and extent
- We can see even tiny defects that might not be visible otherwise
- The dye washes out naturally with your tears within a few minutes
- This quick, painless test provides critical information for treatment planning
For many corneal ulcers, we gently collect a sample of cells from the ulcer surface using corneal scraping with a sterile instrument, and sometimes a swab. This sample is sent to a lab where technicians attempt to grow the organisms and identify exactly which bacteria, fungus, virus, or parasite is causing your infection.
Cultures are especially important for larger, central, or deep ulcers, contact lens related infections, atypical appearing ulcers, cases involving trauma with plant or vegetative matter, patients who are immunocompromised, ulcers in people using steroid eye drops, post-surgical infections, or ulcers that do not respond well to initial treatment. Sometimes cultures do not grow an organism even when infection is present, and we may adjust treatment based on your clinical response and other findings.
Knowing the specific germ helps us choose the most effective medication. Culture results usually take a few days, so we often start you on broad-spectrum treatment right away and adjust based on the lab findings and how your ulcer responds.
In complex or atypical cases, we may order additional imaging or tests. We might also check the pressure inside your eye or examine the back of your eye to make sure the infection has not spread. In selected cases, specialized tests such as confocal microscopy can help identify certain organisms like Acanthamoeba, or we may use PCR testing for viral infections.
Optical coherence tomography is occasionally used as an adjunct to assess corneal depth and structure in specific situations. Blood tests or other medical evaluations may be necessary if we suspect an underlying condition is contributing to your ulcer.
Treatment Options for Corneal Ulcers
The primary treatment for a corneal ulcer is targeted medication in eye drop form. For bacterial ulcers, we often prescribe a high-frequency fluoroquinolone antibiotic drop for many uncomplicated cases. Severe, large, central, or deep bacterial ulcers may require fortified antibiotic drops, sometimes using a combination of two different antibiotics for broader and stronger coverage. Fungal ulcers require antifungal drops, and viral ulcers need antiviral medications.
Acanthamoeba infections require different topical therapy, typically involving specialized antiseptic drops such as biguanides or diamidines used for prolonged periods, often many weeks to months. These treatments are not the same as standard antibiotics, antifungals, or antivirals.
We select medications based on the likely or confirmed organism and the severity of your infection, and adjust treatment as culture results and clinical response guide us. Never use leftover eye drops from a previous condition, especially steroid drops, unless we specifically direct you to do so. Using the wrong medication can worsen your infection and threaten your vision.
Treating a corneal ulcer is intensive, especially in the first few days. Depending on the severity of your ulcer, you may need to apply your eye drops very frequently, sometimes every 30 minutes to every hour around the clock initially. This frequent dosing ensures a constant level of medication on your cornea to fight the infection aggressively. Not everyone needs around-the-clock dosing; your specific schedule depends on the size, depth, location, and organism involved.
- Set alarms to wake you at night for drops if prescribed for severe cases
- We will give you a detailed schedule showing exactly when to use each medication
- As the ulcer improves, we gradually reduce the frequency
- Never skip doses or stop treatment early, even if you feel better
When an ulcer is deep, large, or caused by certain organisms, eye drops alone may not be enough. Oral antiviral medications are commonly prescribed for herpes simplex or herpes zoster infections affecting the eye. Oral antibiotics are reserved for specific situations, such as suspected gonococcal infection, infections with risk of perforation or spread beyond the cornea, or when scleral involvement is present.
Systemic antifungal medications may be added in selected severe fungal infections. In some cases of Acanthamoeba keratitis that do not respond adequately to topical therapy, oral medications may be considered as adjunctive treatment. We will monitor you closely for side effects and adjust the treatment as needed.
If the infection does not respond to medications or if the ulcer has caused significant damage, we may recommend surgical intervention. If the cornea thins severely or threatens perforation, we may use urgent measures such as tissue adhesive, patch grafts, or therapeutic corneal transplant to preserve the structural integrity of your eye.
Procedures can range from removing infected tissue to performing a corneal transplant in severe cases where the cornea is too damaged to heal properly. Amniotic membrane grafts may be used to support healing in selected cases. Photoactivated chromophore corneal cross-linking is an adjunctive treatment that may be considered for certain resistant infections in specialized settings, though it is not yet routine or universally available. We only recommend surgery when necessary and will explain all options thoroughly.
A corneal ulcer can be very painful, but we have several ways to help you stay comfortable. We may prescribe oral pain relievers or recommend over-the-counter options. We often prescribe cycloplegic eye drops, which relax the muscles inside your eye and can significantly reduce pain and light sensitivity.
In selected cases with close follow-up, and depending on the status and type of infection, a bandage contact lens may be considered to protect the cornea and reduce discomfort. This is not appropriate for all ulcers and requires careful supervision. We do not typically use numbing drops for ongoing pain relief because they can slow healing and mask worsening symptoms. If your pain is severe or getting worse despite treatment, contact us right away, as this may signal that the infection is not improving.
Caring for Your Eyes During and After Treatment
Following our care instructions carefully is essential for a successful recovery. Keep your hands clean before touching your eye or applying drops. Avoid rubbing or pressing on your eye, which can worsen the injury and spread infection.
- Do not wear contact lenses until we tell you it is safe
- If your infection is contact lens related, discard your current lenses, case, and solution, or bring them to our office if we need to culture them
- Do not patch your eye closed unless we specifically instruct you to do so, as patching can worsen some infections
- Avoid driving if your vision is reduced or if you are using dilating or cycloplegic eye drops
- Avoid eye makeup, which can introduce new bacteria
- Wear sunglasses outdoors to protect your sensitive eye from light and debris
- Do not swim or expose your eye to water that might contain germs
- Take all medications exactly as prescribed
You will need frequent follow-up appointments so we can track your healing progress. During these visits, we examine the ulcer to see if it is getting smaller, check for new complications, and adjust your medications if necessary.
We typically see patients daily or every few days at first, then less often as the ulcer heals. We look for signs that the infection is clearing, such as reduced redness, less pain, and re-growth of healthy corneal tissue. It is important to keep all scheduled appointments, even if you feel much better.
Returning to contact lens wear too soon can trigger a new infection or slow your recovery. We will let you know when your cornea has healed enough to safely wear lenses again, which often takes weeks and sometimes longer depending on the severity and type of infection.
When you do resume wearing contacts, we may recommend switching to daily disposable lenses, which are safer and reduce infection risk. We will review proper lens hygiene and care practices with you to help prevent future ulcers.
Once you have had a corneal ulcer, taking steps to prevent another one becomes very important. Always follow contact lens care guidelines, replace lenses and cases as directed, and never sleep in lenses unless specifically prescribed for extended wear.
Protect your eyes from injury by wearing safety glasses during risky activities. Seek care promptly for any eye irritation, redness, or pain rather than waiting to see if it goes away on its own. Keeping your eyes healthy and addressing dry eye or other conditions also reduces your future risk.
Frequently Asked Questions
No, a corneal ulcer will not heal safely on its own. While very minor corneal abrasions sometimes improve without intervention, an infected ulcer requires medication to eliminate the organisms causing the damage. Some sterile inflammatory conditions can mimic infectious ulcers, which is why professional evaluation is essential and self-treatment is unsafe. Without proper treatment, an infection will likely worsen, spread deeper, and cause permanent vision loss or serious complications.
Whether a corneal ulcer affects your vision long-term depends on its location, size, and how quickly we treat it. Ulcers in the center of the cornea or those that form deep scars are more likely to cause lasting vision problems. Many patients recover excellent vision with early, aggressive treatment, but some may need glasses, contact lenses, or further procedures to improve vision after healing.
Healing time varies widely based on the infection type and severity. Small bacterial ulcers may heal in one to two weeks with proper treatment, while fungal or deep ulcers can take several weeks to months. You will need to use medications and attend follow-up visits throughout the healing period, and we will monitor your progress closely to ensure recovery stays on track.
This depends on your symptoms, your job or school activities, and how well your treatment is working. Many people need to take at least a few days off initially because of pain, light sensitivity, and the need for frequent medication doses. Jobs that involve heavy machinery, driving, or exposure to dust and debris may require a longer break until your eye is more healed and protected.
Most corneal ulcers are not contagious from person to person. Bacterial, fungal, and Acanthamoeba infections typically occur due to direct contamination of the eye and are not spread through casual contact. Some viral eye infections can be contagious, though herpes keratitis usually results from reactivation of a virus already in your body rather than direct transmission from your infected eye. Good hygiene, such as washing your hands frequently and not sharing eye drops or cosmetics, is always important. If you have concerns about contagion based on your specific infection, we can discuss precautions with you.
Getting Help for Corneal Ulcer (Corneal Infection)
If you experience eye pain, redness, discharge, or vision changes, contact our office immediately for an urgent evaluation. Early diagnosis and treatment are key to protecting your sight and preventing complications from a corneal ulcer. We are here to provide the expert care you need to heal safely and completely.