Progressive Retinal Atrophy (PRA) is an inherited disease which occurs in many canine breeds, including the Labrador Retriever, Australian Cattle Dog (Blue and Red Heelers), and mixed dogs. The disease causes gradual blindness, first affecting dim light vision and eventually resulting in complete blindness many months or years later. The degenerating retina also releases products that can cause secondary cataracts, or opacities to form within the eye, that can themselves cause inflammation. There is no known treatment for PRA. If your dog has secondary cataracts, we may recommend a topical anti-inflammatory medication to decrease the chance of complications such as glaucoma (increased pressure within the eye). Thorough evaluation of the fundus (retina and optic nerve) performed by a board certified ophthalmologist is necessary in order to definitively diagnose PRA.
Genetics play a vital role in the disease and therefore, individuals with the disease should be removed from breeding stock. Dogs related to yours should also be examined for PRA with an eye exam. The owners of related dogs may also want to have an eye electroretinogram (ERG) performed. The ERG is a sensitive indicator of PRA, often times revealing abnormal findings long before clinical signs are apparent.
While the loss of vision can be frustrating for both owners and patients, most dogs adapt well to being blind over time with the help and patience of their owners, and it should be stressed that the disease is NON-PAINFUL.
More Resources:
American College of Veterinary Ophthalmologists: Progressive Retinal Atrophy