Cataracts in Dogs

As dogs live longer lives, alongside their human counterparts, they are more likely to experience age-related issues like cataracts. Cataracts involve clouding of the lenses of the eye. They can drastically impair vision and can even lead to blindness.


If your dog has cataracts, you may notice a white, gray or milky blue-green haziness in the eyes. The eye may become red, indicating inflammation. Your dog may squint, paw at his eyes or bump into things.

The lens lies directly behind the iris. It’s a clear structure that focuses light onto the retina at the back of the eye. Depending on the degree of opacity, a cloudy lens can block light enough to impair vision. A dog with 30% opacity may exhibit no symptoms of vision loss or impairment. But cataracts are progressive. By the time the lens becomes two-thirds clouded, your dog’s vision may be poor enough to cause serious problems.

Risk Factors and Causes

There are various possible causes of cataracts. Some breeds are genetically prone. Among these are miniature poodles, golden retrievers, Boston terriers, miniature schnauzers, American cocker spaniels, and Siberian huskies. Cataracts may develop spontaneously in these breeds, especially after a certain age. Regardless of breed, though, any dog of advanced age may develop cataracts.

Cataracts can signal diabetes. If your dog displays increased thirst, more frequent urination, weight loss, and clouded lenses, diabetes mellitus may be the underlying cause. This obviously merits the immediate attention of your family veterinarian.

Trauma is another possible cause of cataracts. Electric shock, for example, can cause abnormal clouding of the lenses. Other causes may include exposure to toxins or radiation, and abnormally low levels of calcium in the blood.

Diagnosis and Treatment

Don’t delay seeing your family veterinarian if you detect possible signs of cataracts in your dog. Cataracts related to diabetes, for instance, may progress extremely rapidly, causing functional blindness. In such cases, speed is of the essence.

Your veterinarian will take a thorough history, asking for details about the onset of symptoms. He or she may order various tests. Blood and urine tests may be indicated, for example. Although these tests cannot diagnose cataracts specifically, they may indicate related, underlying problems.

As in humans, cataracts can be corrected with surgery. Prior to surgery, additional tests such as electroretinography to test the function of the retina and an ocular ultrasound to visualize behind the lens may be necessary.)

Just as in people, the surgical technique is called phacoemulsification and is performed by a board-certified veterinary ophthalmologist.It involves breaking down the proteins of the lens with ultrasound waves. These emulsified proteins are then sucked out, and fluids are replaced with sterile saltwater. In most cases, an artificial replacement lens is implanted to restore full functional vision in your dog. This relatively simple procedure has proven more than 90% effective in dogs.