Causes and Treatment of Cataracts in Dogs

Elderly dog with mature cataracts
This dog has mature cataracts.

It's not completely uncommon to see cataracts in dogs, especially in older dogs. There are different types of cataracts, and they form for many reasons. Find out what causes them and how they are treated.

About Cataracts in Dogs

A cataract is essentially an opaque or cloudy area that forms when there is a breakdown of the fibers in the lens of a dog's eye. Depending on its size, this breakdown can obscure a dog's vision to some degree. People and animals can both develop cataracts, and cataracts are classed by the amount of obstruction they cause.

  • Incipient - This is a very small cataract that only covers a small portion of the lens and may not yet affect a dog's sight.
  • Immature - This type of cataract covers a little more of the lens and usually causes at least a little blurry vision.
  • Mature - This cataract covers the entire lens and truly interfere's with a dog's sight.
  • Hypermature - This type of cataract evolves from a mature cataract, and the lens actually begins to shrivel. There may be a few clear areas on the lens that allow the dog to see a little, but this depends on just how much function is left in the eye.

What Causes Cataracts

There are numerous causes for cataracts in dogs. Here are some of the most common reasons why they develop.

  • Aging - It's not unusual for an elderly dog to have some degree of cataract formation. However, sometimes what a pet owner believes might be a cataract turns out to be a case of nuclear sclerosis. This condition causes a graying of the lens that typically doesn't affect the dog's vision and doesn't require treatment.
  • Injury - Any type of injury that ruptures the lens can lead to a cataract. Seek your vet's help immediately to determine the extent of the damage and whether or not treatment is necessary to save the dog's eye. Left untreated, the affected eye may develop an infection inside that may not become evident for weeks.
  • Dietary deficiencies - A lack of the essential amino acids phenylalanine and arginine can lead to cataract formation. Using puppy milk formula exclusively, such as is the case with orphaned pups when there is not a lactating bitch available, may also lead to the development of these cataracts. Fortunately, the cloudiness often clears when proper nutrition is restored.
  • Diabetes - Diabetes can cause cataracts to form very quickly, so you should consult your vet immediately if you suddenly notice a cataract forming.
  • Hereditary factors - Some breeds, such as Afghan Hounds, Bichon Frises and Cocker Spaniels, are predisposed to develop cataracts.
  • Congenital factors - This type of cataract is usually present at birth, but it is not generally considered inherited. It may be caused by an infection that occurs while the pup is still in utero.
  • Other eye diseases - Conditions such as progressive retinal atrophy, glaucoma and uveitis (infection related to injuries) can cause cataracts to form.

Surgical Treatment

With the exception of cataracts caused by a nutritional deficiency and the clear areas that may develop with hypermature cataracts, cataracts do not go away on their own. Once the lens becomes cloudy, it will stay that way unless the cataract is surgically removed. Cataract surgery is performed under general anesthesia and involves opening up access to the lens and removing the cloudy tissue. A replacement lens is then put in place, and absorbable sutures are used to close the incision.

Should You Have Your Dog's Cataract Removed?

Since cataracts are not life-threatening, it's not absolutely necessary to remove them unless they truly hamper a dog's quality of life. Most dogs rely more on their sense of smell than their sight. There are definite risks to any type of surgery that may outweigh any potential increase in vision. Your vet will first examine your dog thoroughly to assess his vision. If the vet believes your dog could truly benefit from cataract surgery, he'll run further tests to assess your dog's overall health and determine if he is a good candidate for surgery. Once you have all the facts and your vet's recommendation, you can make an informed decision whether or not you really want your dog to have the surgery.

Possible Prevention

While it may not be completely possible to prevent your dog from ever developing a cataract, there are nutritional supplements high in antioxidants that are designed to enhance the health of your pet's eyes. If your dog has a higher-than-average chance for cataract development due to diabetes, an ocular disease or hereditary factors, speak with your vet about the situation and get his recommendation on whether a nutritional supplement might be beneficial for your pet.

Causes and Treatment of Cataracts in Dogs