Your Dog’s Vision Loss Could be Linked to Cataracts
Like people, as dogs age changes occur in the structure of the eye. As a result, the animal's vision is affected and cataracts can occur.
A cataract is a defect in the lens—actually an opacity in the lens. Cataracts must not be confused with lenticular or nuclear sclerosis, which are a normal aging phenomenon where the lens takes on a cloudier or even bluish appearance. This condition does not cause vision loss, and your veterinarian can easily distinguish it from cataracts.
Cataracts can progress and lead to erosion of vision and blindness. Cataracts are called immature if only a part of the lens is involved. They’re called mature if the entire lens is opaque. The rate of progression of cataracts depends upon the location of the cataract within the lens and the age of the dog. The cataracts induced by diabetes are usually very rapid in their progress.
Your veterinarian can determine the presence of cataracts. Blood work should be done to detect underlying disease processes such as diabetes. Before surgery is considered, the retina must be evaluated to rule out concurrent retinal degeneration. Your veterinarian may refer you to a board-certified veterinary ophthalmologist to determine the extent of your dog's problem and to establish whether your dog is a candidate for surgical cataract repair.
Age itself is not a consideration when thinking about surgery. If the cataracts are small and do not interfere with the dog's vision they may be regularly monitored for progression and left alone. Cataracts in only one eye are often left alone and managed conservatively.
Your veterinarian can best determine if surgery is needed for your dog's cataract. Cataract surgery in dogs has a high rate of success and a good prognosis. But depending upon the type of cataract, not all dogs with cataracts are candidates for surgery.
Originally published in AKC Family Dog in the “Ask Dr. Kevin” column by Kevin Fitzgerald, DVM