Corneal Ulcer (Corneal Infection)
What Is a Corneal Ulcer?
Understanding how a corneal ulcer forms helps explain why fast treatment matters so much. Even a small break in the cornea's surface can allow harmful organisms to enter and cause a painful, vision-threatening infection.
Your cornea helps focus light so you can see clearly. When the outer layer is damaged, bacteria, viruses, fungi, or parasites can invade the tissue and form an open sore. Once inside, the infection breaks down healthy corneal cells and can quickly worsen without treatment.
Even a tiny scratch from a fingernail, contact lens, or piece of debris can serve as an entry point for infection.
The organism causing your ulcer determines how we treat it, which is why identifying the specific type as quickly as possible is so important.
- Bacterial ulcers are the most common, especially in contact lens wearers
- Fungal ulcers often follow an eye injury involving plant material, such as a branch scratch
- Viral ulcers are usually linked to the herpes simplex or herpes zoster virus
- Parasitic ulcers caused by Acanthamoeba are rare but serious, and are most often seen when contact lenses are exposed to contaminated water, including tap water or swimming pools
Each type requires a different treatment approach. It is never safe to use steroid eye drops on your own, as they can severely worsen certain infections, particularly active viral ones.
A corneal ulcer is always a medical urgency. Without prompt treatment, the infection can spread deeper into your eye and cause permanent scarring, vision loss, or in severe cases, loss of the eye itself. The good news is that most corneal ulcers respond well when we catch and treat them early. Our goal is to stop the infection, support healing, and preserve as much of your vision as possible.
Signs and Symptoms of a Corneal Ulcer
Recognizing the warning signs early gives you the best chance of a full recovery. Symptoms can develop quickly and should never be ignored or managed with over-the-counter drops alone.
Most people with a corneal ulcer experience significant pain that ranges from a gritty, foreign-body sensation to intense throbbing. This discomfort often worsens when you blink or when light hits your eye.
- Sharp or burning pain in the affected eye
- A feeling that something is stuck in your eye
- Extreme sensitivity to light, making it hard to keep your eye open
- Pain that does not improve with standard over-the-counter eye drops
- Severe pain that seems out of proportion to 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 infection. Excessive tearing is also common as your eye tries to flush out the irritant.
Discharge can vary by infection type. Bacterial ulcers may produce thick yellow or green drainage, while viral infections tend to cause watery discharge. The absence of heavy discharge does not rule out a serious infection. Any unusual drainage, persistent redness, or excessive tearing should prompt a call to our office right away.
As the infection damages corneal tissue, your vision may become blurry, cloudy, or hazy. In many cases, the ulcer appears as a visible white or gray spot on the surface of the eye. This spot may be small or large depending on severity, and sometimes it 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 or go to an emergency eye care center if you notice any of the following:
- You wear contact lenses and develop eye pain, redness, or light sensitivity
- Decreased or blurred vision in the affected eye
- A white or cloudy spot visible on your cornea
- A recent eye injury involving plant material, soil, or organic matter
- Severe light sensitivity or an inability to keep your eye open
Untreated infections can advance quickly, making treatment more difficult and increasing the risk of permanent damage.
Risk Factors for Corneal Ulcers
Knowing what puts you at higher risk helps you take steps to protect your eyes. Several common habits and health conditions can make the cornea more vulnerable to infection.
Wearing contact lenses is the leading risk factor for corneal ulcers in otherwise healthy people. Lenses can trap bacteria against your cornea, especially when not used or cared for properly.
- Sleeping in contact lenses significantly increases infection risk
- Using tap water or saliva to rinse lenses introduces harmful organisms
- Showering, swimming, or using a hot tub while wearing lenses
- Topping off old solution rather than emptying and refilling your case with fresh solution daily
- Not replacing your lens case regularly allows bacteria to build up
- Wearing old or damaged lenses creates tiny scratches that invite infection
- Certain lens types, such as orthokeratology or extended wear lenses, may carry higher risk
Any trauma to the eye can break the cornea's protective barrier. Scratches from fingernails, tree branches, or airborne debris provide an entry point for germs. Even a small abrasion can develop into an ulcer if bacteria or fungi enter the wound before it heals.
We often see corneal ulcers following workplace injuries, sports accidents, or yard work. Wearing protective eyewear during high-risk activities can prevent many of these injuries.
Healthy tears contain natural defenses that wash away germs and keep the cornea moist. When your eyes do not produce enough tears, or when tears evaporate too quickly, your cornea becomes more vulnerable to infection and injury.
Chronic dry eye, eyelid problems that prevent full blinking, and certain medications can all reduce your natural tear protection. If dry eyes are a factor in your eye health, we can discuss treatment options to improve your tear film and reduce your risk.
When your immune system is compromised by conditions such as diabetes, HIV, or cancer treatment, 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 types.
Using steroid eye drops without close medical supervision also raises your risk, as steroids can suppress the eye's natural defenses and allow infections to take hold or worsen rapidly. Conditions that affect eyelid closure, such as Bell's palsy or thyroid eye disease, can also leave the cornea exposed and less protected.
How We Diagnose a Corneal Ulcer
Accurate diagnosis is essential because different infections require very different treatments. We use a combination of clinical examination, staining techniques, and laboratory testing to identify exactly what is causing your ulcer.
We begin by reviewing your symptoms, medical history, and any recent eye injuries or contact lens use. We then perform a detailed examination using a slit lamp, which is a microscope with a bright focused light that lets us view the structures of your eye in high magnification. This allows us to identify the ulcer, evaluate its size and depth, and check for signs that the infection is spreading.
We typically apply a small amount of a special orange dye called fluorescein to your eye. Under blue light, the dye makes damaged areas of the cornea glow bright green, revealing the size, shape, and location of the ulcer.
- The staining pattern helps us determine the extent of the damage
- Even very small defects become visible that might otherwise be missed
- The dye washes out naturally with your tears within a few minutes
- This quick and painless test provides critical information for guiding treatment
For many ulcers, we gently collect a sample of cells from the ulcer surface using a sterile instrument. This sample is sent to a laboratory where technicians attempt to grow and identify the specific bacteria, fungus, virus, or parasite causing your infection.
Cultures are especially important for larger, central, or deep ulcers, ulcers related to contact lens use, cases involving trauma with plant or organic material, and ulcers that do not respond to initial treatment. Culture results typically take a few days, so we often start broad-spectrum treatment right away and adjust based on lab findings and your response.
In complex or unusual cases, we may use additional tools to guide diagnosis. Confocal microscopy can help identify certain organisms such as Acanthamoeba, and PCR testing may be used for suspected viral infections. Optical coherence tomography (OCT) can assess corneal depth and structure in specific situations. If we suspect an underlying medical condition is contributing to your ulcer, we may recommend blood tests or coordination with your primary care provider.
Treatment Options for Corneal Ulcers
Treatment depends on the type and severity of your infection. We move quickly to start the right medications and monitor your response closely throughout the healing process.
The primary treatment for a corneal ulcer is prescription eye drops targeted to the specific organism involved. Bacterial ulcers are often treated with fluoroquinolone antibiotic drops, while severe or deep infections may require fortified antibiotic drops or a combination of two different antibiotics for stronger coverage. Fungal ulcers require antifungal drops, and viral ulcers need antiviral medications.
Acanthamoeba infections require a different approach altogether, typically involving specialized antiseptic drops used for weeks to months. We select medications based on the likely or confirmed organism and adjust treatment as culture results and clinical response guide us. Never use leftover eye drops from a prior condition, especially steroid drops, unless we specifically direct you to do so.
Treating a corneal ulcer is intensive, especially in the early days. Depending on the severity of your infection, you may need to apply drops very frequently, sometimes every 30 to 60 minutes initially. This high-frequency dosing ensures a constant level of medication on the cornea to fight the infection aggressively.
- Set alarms as needed if around-the-clock dosing is prescribed for severe cases
- We will give you a clear schedule showing exactly when to use each medication
- As the ulcer improves, we will 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 may be added in specific situations, such as when there is risk of perforation or spread beyond the cornea. Systemic antifungal medications may be used in selected severe fungal cases, and in some Acanthamoeba infections that do not respond adequately to topical therapy, oral medications may be considered as well.
A corneal ulcer can be very painful, and we have several ways to help you stay comfortable. We often prescribe cycloplegic eye drops, which relax the muscles inside your eye and can significantly reduce pain and light sensitivity. Oral pain relievers may also be recommended.
We do not typically prescribe numbing drops for ongoing pain relief, because they can slow healing and mask worsening symptoms. If your pain is severe or increasing despite treatment, contact us right away, as this may signal that the infection is not responding as expected.
If the infection does not respond to medication, or if the ulcer has caused significant structural damage, we may recommend a procedure to protect your eye. Options can include tissue adhesive, patch grafts, amniotic membrane grafts to support healing, or in severe cases, a corneal transplant when the cornea is too damaged to heal on its own. Photoactivated chromophore corneal cross-linking is an adjunctive treatment considered for certain resistant infections in specialized settings, though it is not yet a routine option. We only recommend surgery when necessary and will explain all options clearly before proceeding.
Caring for Your Eyes During and After Treatment
How you care for your eye between appointments has a direct impact on how well and how quickly you heal. Following our instructions carefully gives you the best chance of a full recovery.
Keep your hands clean before touching your eye or applying drops. Avoid rubbing or pressing on your eye, which can worsen injury and spread infection.
- Do not wear contact lenses until we confirm it is safe to do so
- If your infection is contact lens related, discard your current lenses, case, and solution
- Do not patch your eye closed unless we specifically instruct you to, as patching can worsen some infections
- Avoid driving if your vision is reduced or if you are using cycloplegic drops
- Avoid eye makeup, which can introduce new bacteria
- Wear sunglasses outdoors to protect your eye from light and debris
- Do not swim or expose your eye to water that may contain harmful organisms
- Take all medications exactly as prescribed and on schedule
You will need frequent follow-up appointments so we can track your healing. We typically see patients daily or every few days at first, then less often as the ulcer improves. During each visit, we examine the ulcer for signs of healing, check for new complications, and adjust your medications if needed. It is important to keep all scheduled appointments, even if you feel much better between visits.
Going back to contact lenses 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 or longer depending on the severity of the infection. When you do resume wear, we may suggest switching to daily disposable lenses, which are generally safer and reduce the risk of future infections. We will also review proper lens hygiene with you before you restart.
After recovering from a corneal ulcer, taking steps to prevent a recurrence becomes a priority. 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 during high-risk activities by wearing safety glasses, and seek care promptly for any new eye pain, redness, or irritation rather than waiting to see if it resolves on its own.
Frequently Asked Questions
Here are answers to questions we often hear from patients dealing with a corneal ulcer for the first time.
An infected corneal ulcer will not heal safely on its own. While minor abrasions sometimes improve without intervention, an active corneal infection requires medication to eliminate the organisms causing the damage. Some sterile inflammatory conditions can look similar to infectious ulcers, which is exactly why professional evaluation is essential. Without treatment, an infection is likely to worsen, spread deeper, and cause permanent damage to your vision.
Whether an ulcer affects your long-term vision depends on its location, size, and how quickly treatment begins. Ulcers in the center of the cornea or those that form deep scars carry a higher risk of lasting vision changes. Many patients recover excellent vision with early and aggressive treatment. Some may need updated glasses, specialty contact lenses, or further procedures after healing to achieve their best vision.
Healing time varies widely. Small bacterial ulcers may improve significantly within one to two weeks with proper treatment, while fungal, parasitic, or deep ulcers can take several weeks to months. The medication schedule and frequency of follow-up visits reflect how serious the infection is. We will monitor your progress closely and let you know what to expect at each stage of recovery.
This depends on your symptoms, the nature of your job or school activities, and how well treatment is working. Many patients need at least a few days off at the start because of pain, light sensitivity, and the need for very frequent medication doses. Jobs that involve driving, operating machinery, or exposure to dust and debris may require a longer break until your eye is well enough protected. We can advise you based on your specific situation and how your healing is progressing.
Most corneal ulcers are not contagious from person to person. Bacterial, fungal, and Acanthamoeba infections typically result from direct contamination of the eye and are not spread through casual contact. Some viral eye infections can be contagious in certain circumstances, though herpes keratitis usually results from reactivation of a virus already present in your body rather than direct transmission. Washing your hands frequently and not sharing eye drops or cosmetics is always a good practice. If you have concerns about contagion related to your specific infection, we are happy to discuss what precautions make sense for you.
Delayed treatment significantly increases the risk of serious and permanent complications. An untreated infection can penetrate deeper layers of the cornea, cause dense scarring, or in worst-case scenarios threaten the structural integrity of the entire eye. Some rapidly progressing infections can cause corneal perforation, which is a sight-threatening emergency. This is why we treat corneal ulcers as urgent conditions and encourage patients to contact us at the first sign of eye pain, redness, or vision change rather than waiting.
Expert Corneal Care at Rhode Island Eye Institute
If you are experiencing eye pain, redness, discharge, or vision changes, we encourage you to contact Rhode Island Eye Institute right away for an urgent evaluation. Our cornea specialists provide the focused, experienced care needed to diagnose and treat corneal infections quickly and effectively. We are committed to protecting your vision and helping you heal safely, with compassionate support every step of the way.