What are Corneal Ulcers in Cats?
What is it?
How is it Treated?
Breed Predispositions
Persian cats, Siamese cats, and Himalayan cats
introduction
When Jenny noticed that her usually playful and energetic cat, Luna, was squinting and keeping one eye closed, she grew increasingly concerned. Luna was never one to shy away from her favorite toy, but she seemed disinterested and uncomfortable. Alarmed, Jenny took Luna to the vet, where she discovered that her precious cat had developed a corneal ulcer.
Corneal ulcers in cats, or superficial ulcerative keratitis, are open sores on the cornea’s surface caused by infection or trauma. A corneal ulcer appears as a small red spot surrounded by a white ring. When it occurs in one eye, it is called unilateral. If it happens in both eyes, it is called bilateral. This area gradually enlarges and turns into a cloudy patch. In severe cases, it can spread across the entire cornea.
Corneal ulcers usually start with an abrasion or some form of trauma to the eye that then gets infected. Ulcers can also be caused by bacterial infections, feline herpesvirus, chemical burns or allergic reactions to foreign objects like grass awns. Cat owners should always pay attention to any changes in their pet’s eyes which may signal a problem with an ulcer.
They usually occur because of injury to the eyes. In some cases, however, they may be caused by diseases such as bacterial infection. These ulcers may also form during surgery.
What is the Cornea?
The cornea is a transparent tissue located directly behind the eye’s iris. It protects the front part of the eye and helps focus light onto the retina. It is composed of three distinct layers. The outermost layer is called the epithelium.
This thin membrane acts like a window that allows light into the eye. Next is Bowman’s Layer, followed by Descemet’s Membrane. These three layers make up the stroma. The anterior chamber lies above the stroma and contains the crystalline lens. Finally, the posterior chamber lies beneath the stroma and has vitreous humor.
An infection in the cornea may cause it to become cloudy or opaque. If left untreated, ulceration may develop. A superficial ulcer is caused by blunt trauma or irritation. A deep ulcer occurs due to bacterial infections. Superficial ulcers usually heal within one week, while deep ulcers require treatment.

What Causes Corneal Ulcers in Cats?
Cat owners seek veterinary care for their pets because trauma is the number one reason. Corneal ulceration is painful and often requires surgery to heal. In some cases, it is necessary to replace the eye altogether. There are many different types of corneal ulcers in cats. They include chemical burns, viral infections, bacterial infections, trauma, foreign bodies, and nutritional deficiencies.
Chemical Burns
Corneal ulcers caused by chemicals are infrequent in cats. Some substances that could lead to a corneal burn include household cleaners, nail polish remover, and antifreeze. Cats exposed to these substances typically experience pain within 24 hours. If left untreated, the ulcer can progress into a severe form called keratitis sicca syndrome. This type of ulcer usually requires surgical intervention.
Viral Infections
A viral infection of the eyes is much more common in cats than dogs. Feline herpesvirus 1 (FHV1), feline calicivirus (FCV), feline panleukopenia virus (FPLV), and feline infectious peritonitis virus (FIPV) are just a few viruses that can infect the eyes of cats. These viruses can cause conjunctivitis, uveitis, retinitis, and even blindness. Most cats recover from mild symptoms, but those infected with FHV1 or FCV can develop the chronic ocular disease.
Foreign Bodies
Infectious agents such as bacteria, fungi, and protozoa can enter the body through the eyes. When this happens, the eyes become susceptible to infection. The source of the disease is often something the cat picked up outside. For example, a cat might pick up sand or dirt while playing outdoors. Once inside the cat, the agent spreads throughout the bloodstream. Although most foreign bodies do not penetrate the cornea, they can still cause damage to the delicate tissue lining the eye.
Nutritional Deficiency
The cornea is made up of collagen fibers. Collagen is an essential protein found in all living cells. It provides structure and strength to tissues. Unfortunately, certain nutrients help maintain healthy collagen levels in the body. Vitamin C, E, zinc, copper, selenium, and omega-3 fatty acids are essential vitamins and minerals to keep the cornea healthy. The lack of any of these nutrients can result in collagen deficiency. As a result, the cornea becomes thin and brittle.
Signs and Symptoms of Feline Corneal Ulceration
Corneal ulceration is usually painless and doesn’t cause redness or discharge. However, you might notice tiny white spots on the eye’s surface. These spots are called satellite lesions. Satellite lesions indicate the presence of a cornea ulcer.
The symptoms of cornea ulcers include blurred vision, sensitivity to light, itching, watering, tearing, and pain. If left untreated, a cornea ulcer can permanently damage the eye.
Diagnosis of Corneal Ulceration in Cats

A fluorescein dye eye test is the most effective way of diagnosing cat eye ulcers. Your vet will take several steps before making a diagnosis, including taking a history, performing a physical examination, collecting samples, and doing tests such as cytology, culture, and biopsy. If you suspect your cat has a corneal infection, ask your vet how they plan to proceed.
Fluorescein dye testing involves placing drops into each corner of your cat’s eyes. After five minutes, your vet will look into your cat’s pupils to see whether there are areas where the iris appears darker than usual. This indicates that the dye has entered the cornea. Next, your vet will examine your cat’s cornea under a microscope to determine whether it contains white spots or flecks of blood. These indicate bacterial infections and may lead to loss of vision.
Your vet may use one of three methods to collect samples for diagnostic purposes. Cytology involves scraping cells off the surface of the cornea. Culture consists in growing bacteria in a petri dish. Finally, a biopsy involves cutting out a small tissue for microscopic analysis.

Treatment for Corneal Ulcers in Cats
If your cat has been diagnosed with Corneal ulceration, treatment options include topical medications, antibiotics, surgery, and euthanasia.
The first step to treating a corneal ulcer is to clean the area around the ulcer. You should use warm water and soap to wash away debris and dirt. Next, apply antibiotic ointments or drops directly onto the affected areas. These medications must be used carefully since they can irritate sensitive tissues. After washing off the cream, pat dries the area gently.
Topical Medications
There are many different types of topical medications available to treat corneal ulcers. Some of the more common ones include:
- Neomycin sulfate (Neosporin) – this medication helps prevent bacteria’s further growth by killing the already present bacteria.
- Polymyxin B Sulfates (Polysporin) –This medication kills bacteria by binding to their cell walls. It also prevents them from attaching to other parts of the body.
- Gentamicin – this medication treats bacterial infections by destroying the outer membrane of the bacteria.
Surgery
Surgical therapy may be necessary if the ulcer penetrates the deeper layers of the eye. To perform this surgical technique, your veterinarian will make a small incision near the edge of the ulcer. They will then insert a needle into the ulcer and inject antibiotics into the infected area. Once the medication has been injected, they will close the wound with sutures.
Antibiotics
In many cases, the ulcer heals without surgery. If the ulcer worsens, your veterinarian may recommend another round of antibiotic drops to help control the infection. The ulcer may heal naturally if it does not penetrate too deeply into the eye. If the ulcer is more profound than 50% of the cornea, or if treatment doesn’t show results, seek a board-certified veterinary eye doctor.
Recovery After Treating Corneal Ulcers in Cats
The recovery begins after the cat is treated for a corneal ulcer. Reducing the size of the ulcer and preventing further damage to the eye are necessary steps in achieving a successful recovery. Keeping the wound clean is also essential in helping the cornea heal and avoiding any possible infection.
Your veterinarian may recommend applying an ophthalmic ointment or drops to the affected eye multiple times daily for several weeks to provide lubrication, ease discomfort, and protect against further injury.
Sometimes, bandaging the eye may be necessary to protect it while it heals. Talk to your veterinarian about how long your pet must wear a bandage and how often it should be changed during this time frame.
During this period of recovery, regular check-ups with your vet are essential as they want to monitor your pet’s progress and ensure that everything is generally progressing according to plan. Depending on the ulcer’s extent, complete healing may take one week and three months before signs of improvement are seen./
When it comes time for follow-up visits with your veterinarian during their recovery phase, you want to make sure they keep track of changes in vision, such as pupil size or cloudiness, that could indicate additional issues arising from their condition of glaucoma or cataracts if not monitored carefully. Additionally, monitoring for abnormal discharge from either eye requiring further veterinary attention should also be noted.
Once fully healed over time, there should cease any evidence of an ulcer, including swelling or redness, all common side effects that dissipate soon after successful treatment. However, despite the initial success rate of therapy, it’s still possible for blepharospasm (eye twitching), which may become problematic if not appropriately addressed by an extended treatment regimen prescribed by your vet as preventative maintenance moving forward!
Prevention of Cat Corneal Ulcer
Corneal ulcers can be painful and potentially dangerous for cats, so preventing them should be a priority. Here are some tips to help.
First, keep your cat’s environment clean and free from foreign objects that could scratch its eyes. Then, regularly inspect your cat’s eyes for any signs of irritation or redness, and take it to the vet if you see anything unusual.
Maintaining good hygiene is critical. Keep long hair out of your cat’s face by routinely brushing it, especially around the eyes. In addition, regularly groom your cat with a soft damp cloth to remove dirt and debris that might lodge in its eyes or get into its tear ducts.
Also, ensure your cat provides adequate nutrition by feeding it high-quality food packed with vitamins and minerals, such as green vegetables, fish, chicken and other proteins, and healthy fats like olive oil or salmon oil. These nutrients are essential in keeping the eye area healthy and strong enough to prevent infection.
Finally, be aware of any medications your pet may be taking; some drugs can cause dry eye, increasing the risk of corneal ulceration in cats. If this applies to your pet, talk to the vet about possible solutions, such as topical drops or special diets, as soon as possible.
Following these tips can help protect against corneal ulcers in cats and ensure their eyes remain healthy and clear!
Frequently Asked Questions
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