Cataracts in Dogs
When discussing cataracts in dogs, it can be useful to think of our pet’s eyes as fully functional cameras. Just like a camera lens that becomes smudged or dirty, it causes the picture we take to become blurred and less clear. When a cataract develops, a white cloudiness within the crystalline lens occurs, causing a partial to complete opacity. As this disease process worsens over time, the entire lens can become cloudy, and functional vision becomes lost. Usually, when we think of cataracts we commonly associate them with Geriatric Dogs. There are actually a number of reasons why your dog developed a cataract; the most common causes being genetics and diabetes.
Cataracts can be categorized by age of onset, amount of vision loss, or location within the lens where they are forming. Some of these include primary vs. secondary; congenital, juvenile, or senile; or incipient, immature, mature, hypermature. Symptoms of cataracts present in your dog’s eyes correlate to the degree of visual damage. Dogs who have a visual opacity of less than 30 percent have nearly no visual symptoms, whereas dogs who have more than 60 percent may have a noticeable loss of vision.
Cataracts may be classified by cause (i.e. primary, secondary); age of onset (e.g. congenital, juvenile, senile); location within the lens (e.g. capsular, anterior cortical, posterior cortical, Y-sutural, nuclear, axial, paraxial, equatorial); and degree of completeness (i.e. incipient, immature, mature, hypermature). Precise localization of the cataract within the lens and characterization of the cataract typically require slit-lamp biomicroscopy by a veterinary ophthalmologist.
Cataracts form for many reasons, and an underlying disease state is sometimes present, however, the most common reason is genetic/inherited traits. When a disease state is the cause, veterinarians will look for a history of diabetes, trauma, nutritional disorders, exposure to radiation, and age-related disease. It is important to note that diabetes is the second most common cause of cataracts in dogs. If your dog has a history of weight loss, increased drinking and urination, and a whitish color to his eyes, he should be evaluated by your veterinarian and tested for diabetes.
The most common symptoms of cataracts are:
• A white layer notable on the eye
• Irritation to the eye, discharge
• Rubbing of the eyes
• Change in behavior such as no longer jumping up on the furniture
If you take notice of cloudiness in one or both of your dog’s eyes, you should make an appointment at our veterinary hospital for your pet to be evaluated. One of our veterinarians will ask you questions about any possible incidents or unusual behavior cues that your dog may be displaying. A Physical Exam will then be performed on your pet, paying careful attention to his eyes performed with an ophthalmoscope. If diabetes is suspected, other tests, including blood work and urinalysis, may be suggested to look for diabetes or other conditions.
Surgical correction is currently the only effective treatment for cataracts, although ocular medications are often used to help prevent secondary problems which can occur resulting from the cataract formation. If you suspect your dog has a cataract, please call one of our offices to schedule an appointment.