Dog Eye Ulcer: Symptoms, Treatment, and Prevention

A dog eye ulcer, also called a corneal ulcer, occurs when the cornea is scratched or otherwise damaged. Eye ulcers can be very painful and may cause squinting, redness, or eye discharge.

If you notice signs of a dog eye ulcer, have your pet examined by a veterinarian.

What Is a Dog Eye Ulcer?

A dog eye ulcer—also called a corneal ulcer or ulcerative keratitis—is a condition in which the outer layer of the eye (the cornea) erodes or becomes damaged, causing a divot or dent.

The damage can be superficial (on the surface) or affect deeper layers of the eye.

Dog eye ulcers can cause pain, eye redness, eye discharge, frequent blinking, holding the eye closed, and sometimes swelling.

Dog eye ulcers are common and are diagnosed most often in brachycephalic (flat-nosed) breeds, but they can affect any breed of dog.

What Are the Symptoms of a Dog Eye Ulcer?

Symptoms of a dog eye ulcer can range from mild to severe and may include frequent blinking, excessive tearing, eye redness or swelling, pawing at the eye, holding the eye closed, and eye discharge.

Symptoms in order of severity include:

• Blinking the eye
• Excessive tearing
• Redness of the eye
• Swelling of the eyelid or skin around the affected eye
• Pawing at the eye or rubbing their face on the ground
• Elevated third eyelid (the third eyelid is in the inner corner of the eye)
• Holding the eye completely shut
• Yellow, green, or bloody eye discharge
• Hole (perforation) in the outer layer of the eye or rupture of the eye
• Blindness in the affected eye
• Decreased appetite
• Lethargy or hiding behavior

What Causes Dog Eye Ulcers?

Dog eye ulcers can develop when the normal outer layer of the eye (cornea) is disrupted or its structure, function, or physiology is affected. The most common causes are trauma, foreign body injuries, and chemical burns.

Causes of dog eye ulcers include:

• Trauma: Scratches from another animal; running into tree branches, plants, or bushes; or self-inflicted trauma from rubbing the face.
• Foreign bodies: Sand, dirt, or other foreign material, such as foxtails, can enter the eye and become stuck behind the eyelids, causing repeated damage to the cornea.
• Chemical irritation or burns: Shampoos, topical medications, or household cleaning products can get into the eye.
• Bacterial infections: Such as Pseudomonas.
• Viral infections: Such as adenovirus or distemper.
• Eye conformation or congenital issues: These include abnormal eyelash growth (distichia), eyelid masses or tumors, or entropion.
• Chronic dry eye: Also called keratoconjunctivitis sicca.
• Neurologic issues: Some neurologic conditions do not allow the eyes to blink appropriately.
• Certain endocrine diseases: These include diabetes mellitus, Cushing's disease, and hypothyroidism.
• Inherited conditions: These include conditions such as epithelial dystrophy, most commonly seen in Boxers, Cavalier King Charles Spaniels, Beagles, Cocker Spaniels, Afghan Hounds, and Alaskan Malamutes.

How Is a Dog Eye Ulcer Diagnosed?

Veterinarians diagnose a dog eye ulcer with a thorough eye examination and diagnostic tests that can identify the ulcer and help determine its cause and treatment.

Your veterinarian will first examine your dog's eye for foreign objects, obvious lacerations, abnormal eyelashes, and masses.

Diagnostic tests may include:

• Fluorescein stain: A bright, fluorescent green liquid stain is dropped into the eye and settles in any ulcers, making them light up under blue light during the ophthalmic exam.
• Schirmer tear test: Tiny strips of absorbent paper wick up the tear film from the eye to test for dry eye.
• Intraocular pressure (tonometry): The veterinarian first numbs the eye with a topical anesthetic drop. A Tono-Pen is then used to gently touch the surface of the eye and measure pressure inside the eye. This test screens for uveitis and glaucoma.
• Bacterial culture: A sterile swab is used to collect a sample from the conjunctival sac near the corner of the eye. The sample is sent for culture, where bacterial growth can help the veterinarian diagnose a bacterial infection.
• Cytology: Cells are collected from the surface of the eye and examined under a microscope.

Simple vs. Complicated Dog Eye Ulcers

An important part of diagnosing and treating dog eye ulcers is determining whether the ulcer is simple or complicated.

• Simple (uncomplicated) eye ulcer: A simple ulcer only involves the most superficial (surface) layer of the cornea and usually heals within seven to 10 days without progressing into the deeper corneal layers.
• Complicated eye ulcer: A complicated ulcer extends into the deeper layers of the cornea and can become infected or begin “melting” the deeper layers because of severe swelling and microorganism invasion.

How Are Dog Eye Ulcers Treated?

Treatment for dog eye ulcers depends on the type and severity of the corneal ulcer. Treatment may include medical therapy or surgery.

Medical Treatment

Medical treatment primarily involves topical eye medications. Ofloxacin and NeoPolyBac are commonly prescribed eye antibiotics used to treat simple corneal ulcers.

Serum therapy may also be recommended. Your veterinarian collects blood from your dog, allows it to clot in a serum separator tube, spins it down, and removes the serum. The serum helps slow the breakdown of the cornea to allow for faster healing and must be kept refrigerated.

Atropine eye drops may be prescribed to help reduce ocular pain. Oral anti-inflammatory pain medication, such as carprofen, may also be prescribed to help keep your dog comfortable while their eye heals.

Surgery for Dog Eye Ulcers

Complicated or indolent eye ulcers may require surgery to heal. These ulcers often have a lip of unhealthy tissue that needs to be removed for the cornea to heal.

During surgery, the excess unhealthy tissue is removed. The surface is often scored in a grid and then debrided to help promote good blood flow and appropriate healing.

Sometimes, a bandage contact lens is applied after surgery to protect the site.

Dog Eye Ulcer Recovery and Management

Most simple dog eye ulcers heal with appropriate treatment and have an excellent prognosis for full recovery. They are typically rechecked by a veterinarian within five to seven days to assess healing.

Simple Dog Eye Ulcers

Most simple ulcers heal within the five-to-seven-day recheck period with the right therapy.

Complicated Dog Eye Ulcers

Deeper or more complicated ulcers require closer monitoring and are usually rechecked one to two days after diagnosis to make sure they are improving and not worsening.

Some dogs may require hospitalization for frequent treatments every two to four hours. Medications may be changed or extended based on bacterial culture and cytology results.

For melting, deep stromal, or complicated eye ulcers, referral to a veterinary ophthalmologist (eye doctor) is usually recommended for treatment and surgical intervention.

Conjunctival grafts are usually left in place for two to three months.

Complicated ulcers are monitored closely by a veterinarian for several weeks after surgery or therapy to assess tear production. Tear production may require medical management for a short period of time or, in some cases, permanently.

Managing Underlying Conditions

Underlying medical conditions or congenital abnormalities must also be diagnosed and treated to help avoid chronic eye ulcers or frequent development of corneal ulcers in the future.

How To Prevent Dog Eye Ulcers

You can help prevent dog eye ulcers by reducing situations where your dog's eye could be scratched or otherwise injured.

• Prevent scratching and rubbing. If your dog is itchy, rubbing, or pawing at their face, consider a recovery collar to help prevent them from accidentally scratching their eye.

• Avoid rough play that could injure the eye. Avoid letting your dog roughhouse with cats or other dogs that are likely to bite or scratch their eyes.
  
  This is especially important for brachycephalic breeds, such as Pugs and Boston Terriers, because their eyes are more readily injured.
• Avoid tall weeds. Prevent your dog from running through tall weeds where they are likely to sustain an eye injury.