Cataracts in Dogs – Pet tip 136
The word cataract is probably one you’ve heard before. Perhaps it was in reference to your parents or grandparents, or maybe even from your own doctor. It might surprise you, however, to hear about cataracts from your veterinarian. Most dog owners don’t know that cataracts are actually one of the most common eye problems their pet may develop. Cataracts can occur in all breeds of dog at any age, so it is important for dog owners to be informed about the condition.
Cataracts are the result of a breakdown of the fibres which make up the lens of the eye (in fact, the word ‘cataract’ literally means ‘break down’ in Latin). The lens, which is normally clear in a healthy individual, is used for focusing and allows for sharp, accurate vision. When lens fibres break down, the lens loses its transparency and becomes cloudy. If the cataract is very small, it may not affect the animal’s vision at all. A slightly larger opacity will cause blurry vision, and a cataract that affects the entire lens will eliminate functional vision entirely.
There are multiple forms and causes of cataracts in dogs. Most commonly, the disease is genetic in origin. Dogs with the inherited form of cataracts may present with the condition from birth (congenital cataracts) or develop it at a young age (early onset cataracts). Certain breeds are known to be at a higher risk of inheriting cataracts, including Cocker Spaniels, German Shepherds, Golden Retrievers, Labrador Retrievers, Siberian Huskies, Standard Poodles, Boston Terriers, and Miniature Schnauzers. Other factors, such as infections, toxins, or trauma can also explain congenital and early onset cataracts. Diabetes mellitus is also associated with the development of early onset cataracts. Determining whether or not the disease is genetic in origin is important for owners who intend to breed their animals. Senile (late onset) cataracts can also occur in dogs, though it is far less common in dogs than it is in people. More commonly, a condition called nuclear sclerosis will cause a greying of lens in older dogs. While this may appear similar to cataracts, it is a normal change in the eyes of geriatric dogs and does not usually affect vision.
If your dog is diagnosed with cataracts, there is treatment available. While there is no current method to restore clarity to an already damaged lens, a veterinary ophthalmologist will be able to improve your dog’s vision through surgical removal and replacement of the entire lens. The procedure, which is the exact same treatment used in human cataracts, involves making a small incision in the capsular bag that holds the lens. The original lens is replaced with an artificial one, and the capsule is sutured back together again. Because of the delicate nature of the procedure, the surgery is conducted under a high magnification surgical microscope. Unsurprisingly, this costs of such a procedure can run high, but most owners notice an incredible improvement in their dog’s vision following the surgery.
Unfortunately, not all dogs are good candidates for this procedure. Overly aggressive dogs, those with uncontrolled diabetes, or those who are in otherwise poor health have a less positive prognosis. Even in the healthiest dogs, owners should be prepared for a major recovery period which will include administering prescription eye drops and attending several post-operative recheck appointments. It is important to spend some time discussing all of these details with your veterinarian to determine if surgery is the best option for you and your dog.
By Alison Norwich – Pets.ca writer