5 Common Eye Problems in Elderly Dogs

Published: 10/4/2021

Dogs go through many physiological changes as they age, and that includes changes within the eye. Unfortunately, these changes are rarely for the better, and many of our four-legged friends experience eye problems in their later years.

Eye problems arise in elderly dogs for several reasons. Injuries to the eye, underlying conditions, and simply getting old can cause various eye conditions in canines. We’ll discuss some of the most common eye problems in elderly dogs so you know what to watch out for when your pet enters their golden years.

The cornea is a layer of tissue that lies over the iris and pupil. The cornea shields the eye from debris and helps control the flow of light into the pupil. When calcium or fat-soluble molecules called lipids accumulate in the corneal stroma, it can cause deterioration of this vital eye structure — a condition called corneal degeneration. This eye condition is quite common in senior dogs with a history of eye injuries or underlying conditions.

Symptoms

• White spot in one or both eyes
• Chronic eye pain
• Progressive vision loss

Causes

The causes of corneal degeneration usually fall into 2 categories: injury or underlying illness. Degeneration of the cornea primarily affects senior dogs with pre-existing conditions like high cholesterol, hypercalcemia, and hyperadrenocorticism. This eye condition has also been linked to:

• Diabetes
• Cushing's disease
• Low blood phosphorus
• Pancreatitis
• Vitamin D toxicity
• Eye trauma
• Prolonged eye inflammation

Diagnosis

Vets must perform several tests to come to the diagnosis of corneal degeneration. First, the vet will visually inspect the eye for deformities or injuries. The next step is to administer a fluorescent stain test. 

During the fluorescent stain test, the vet will administer a fluorescent dye to both eyes and examine them under an ultraviolet light. Unlike some eye conditions, the dye will not collect in the cornea of dogs with corneal degeneration. A positive diagnosis can be made if the eye appearance and fluorescent stain test results are consistent with corneal degeneration.

Certain breeds that have these results may be diagnosed with a similar hereditary condition called corneal dystrophy, which mimics the appearance of corneal degeneration. These breeds include Beagles, Cocker Spaniels, Airedale Terriers, Huskies, and Shetland Sheepdogs.

If the dog's results indicate corneal degeneration, further testing will be necessary to find the root cause of the condition. Vets will usually order a thyroid test and blood chemistry panel to check the pet's cholesterol, thyroid, and organ function.

Treatment

Unfortunately, there is little vets can do for corneal degeneration aside from treating the underlying condition. Treatment for the primary disease may reduce the size of the corneal deposits, but not always. Prescription eye drops may also improve the cloudy appearance of the eye.

Average cost of treatment: $300–$3,500

Iris atrophy is another common eye problem in elderly dogs. The iris is a duo of muscles that expand and constrict to allow light into the eye. As dogs age, the muscles within the iris don't work as well as they once did. 

While this condition doesn't cause vision problems, it does change the appearance of the eye. Iris atrophy tends to be more prevalent in small breeds, though larger breeds may also develop this condition.

Symptoms

• Changes in iris appearance (dulling, increase in translucence, or the appearance of black dots)
• Increased sensitivity to light
• Changes in the pupil appearance
• Irregular pupil size
• Fixed and dilated pupil
• Corneal swelling
• Decrease in the thickness of the iris

Causes

Typically, iris atrophy is a product of aging due to the weakening of the iris muscles, though there can be other contributing factors. For instance, iris atrophy is often a comorbid condition in dogs with glaucoma or uveitis. Inflammation as a result of eye trauma is another leading cause of secondary iris atrophy.

Diagnosis

The first step in diagnosing iris atrophy is for the vet to review the pet's medical history report and document any symptoms and pre-existing conditions. Your vet will want to know if your dog has ever sustained injuries to the eye or been diagnosed with glaucoma.

From there, your vet will likely perform a series of tests to rule out other eye conditions that affect the iris. These tests will check the intraocular pressure, examine the eye structures, and check for neurological problems that could contribute to the symptoms. Dogs with ocular trauma may be subject to additional testing, including x-rays and imaging scans.

Treatment

There's no treatment for age-related iris atrophy, but thankfully, it doesn't cause vision loss or pain in dogs. Secondary iris atrophy due to glaucoma or chronic uveitis is often responsive to treatment for the underlying condition. Treatment for trauma-related iris atrophy varies considerably and may require surgery and medication.

Average cost of treatment: $185–$2,420

Cataracts is one of the most well-known age-related eye conditions in both dogs and humans. Cataracts give the eye a hazy appearance that may appear grey or blue in the light. This condition affects the proteins within the eye lens and can cause progressive vision loss, eventually leading to total blindness. Nuclear sclerosis is often mistaken for cataracts since it has a similar appearance, though it doesn't cause vision loss like cataracts.

Symptoms

• Cloudy eyes
• Change in eye color
• Glowing appearance to the eye when light reflects off them
• Signs of vision impairment (running into objects or an inability to recognize familiar people)

Causes

Genetics often play a role in the development of cataracts, but the condition can also be related to underlying systemic or ocular disease. Cataracts often occur in diabetic dogs due to the presence of excess glucose in the eye fluid. Exposure to radiation and toxins can also trigger cataract formation.

Other causes of cataracts include:

• Eye trauma
• Inflammation of the uvea
• Low calcium levels

Diagnosis

Diagnosis of cataracts requires a thorough eye exam since cataracts are difficult to distinguish from nuclear sclerosis. Veterinarians may request additional blood and urine tests after a cataract diagnosis to determine if underlying conditions like diabetes are at play.

Treatment

Unfortunately, surgical intervention is the only way to get rid of cataracts. Phacoemulsification is the most common technique to treat cataracts in both dogs and humans. During phacoemulsification, the vet inserts an ultrasonic device called a phaco probe into the cornea. The phaco probe emits ultrasonic vibrations to disintegrate the eye lens. The vet will then use the same device to extract the remnants of the disintegrated lens and replace it with an intraocular implant.

Average cost of treatment: $500–$5,500

Glaucoma is a devastating and aggressive condition that can cause dogs to lose their eyesight in a matter of hours from symptom onset. Glaucoma is defined as an increase in intraocular pressure due to an inability to drain fluid from the eye.

Symptoms

• Frequent blinking
• Recession of the eye into the orbital socket
• Eye pain
• Pawing at the eyes
• Uneven pupil size
• Eye redness
• Pronounced blood vessels in the whites of the eye
• Pupils that do not constrict when exposed to light
• New or increased tearing
• Poor or absent blink response
• Swelling of the eyes
• Vision impairment or loss

Causes

Glaucoma may be inherited or brought on by an underlying illness or injury. Infections or inflammation of the inner eye can inhibit the flow of eye fluid leading to glaucoma. Other conditions that can lead to improper drainage and glaucoma include:

• Tumors
• Dislocation of the eye lens
• Bleeding within the eye

Diagnosis

To diagnose glaucoma, vets will need to perform a tonometry test that measures the pressure within the eye. Vets must also consider the pet's history, breed, and any recent trauma when determining their diagnosis of primary or secondary glaucoma.

Eye abscesses, tumors, and swelling due to injuries can mimic the symptoms of glaucoma, so vets will often perform X-rays to ensure a correct diagnosis and treatment plan.

Treatment

Treatment for glaucoma will depend on the pet's general health as well as the severity of the glaucoma. Medications like pressure-lowering prescription eye drops may be effective in the early stages.

Pets may also be prescribed beta-blockers or diuretics, which can lower the intraocular pressure by decreasing fluid output. The vet may also recommend a steroid if the dog is experiencing glaucoma related to inflammation. 

More severe cases of glaucoma do require surgery. There are 3 main surgical approaches that vets may take to deal with glaucoma in dogs: cyclophotocoagulation, gonioimplantation, and enucleation.

• Cyclophotocoagulation uses a laser to remove the eye structures that produce eye fluid.
  
• Gonioimplantation is the implantation of a small tube and pump that decreases eye pressure by regulating fluid flow throughout the eye.
  
• When all else fails, enucleation, or eyeball removal, may be necessary to ensure the dog is no longer in pain.

Average cost of treatment: $500–$3,500

Macular degeneration is the progressive breakdown of the macula, a tiny structure within the retina that helps discern hues and features both up close and at a distance.

Symptoms

• Sensitivity to bright light
• Lack of depth perception
• Falls or accidents 
• No longer recognizing familiar people
• Relying more on smell
• Inability to locate common features of the home
• Night blindness

Causes

Experts are still unsure of the exact cause of macular degeneration, but most suspect that genetics play a factor. Some lifestyle factors may predispose a dog to this condition, including:

• Being overweight
• Secondhand smoke
• High blood pressure
• Sex (macular degeneration is more common in females)
  

Diagnosis

Diagnosis of macular degeneration requires electroretinography in addition to an eye exam. Electroretinography allows vets to record the electrical responses of cells within the retina to determine if they are working correctly.

Treatment

Unfortunately, there are no treatments currently available for macular degeneration in dogs. However, there are promising results from gene therapy studies in dogs with this condition.

Average cost of treatment: $200–$600

Eye problems in elderly dogs are common and can be costly to treat. A comprehensive insurance policy for your pet can help you deal with costs associated with eye care. Check out our insurance comparison tool to compare rates among the top pet insurance providers.