Progressive Retinal Atrophy
What is Progressive Retinal Atrophy? Progressive Retinal Atrophy (PRA) is the umbrella term that describes a group of diseases that causes degeneration in the photoreceptor cells inside the retina in cats. The retina is the part of the eye that receives light and contains photoreceptors known as rods and cones. PRA steadily impairs vision in both eyes and leads to blindness. PRA is more commonly found in dogs than in cats.
How does my cat get Progressive Retinal Atrophy? This is primarily an inherited condition. In rare instances, taurine deficiency can contribute to PRA. Taurine is an essential amino acid found in commercial cat food.
How do I know if my cat has Progressive Retinal Atrophy? The warning signs are more behavioral than physical. Typically, cats affected with PRA seem to sport healthy eyes and exhibit no signs of squinting, redness or tearing. However, you will notice that they begin to act more clumsily. They will start bumping into objects, especially at night, or hesitate when climbing stairs or walking down dark hallways. As the disease progresses, you may notice that the pupils become dilated. Your veterinarian will need to perform a thorough physical exam and diagnostic tests to properly identify this eye condition in your cat and rule out other possible causes. Special eye tests, including a Schirmer tear test, tonometry test, and pupil light reflex test, may be conducted. A veterinary ophthalmologist will use a special test called an electroretinogram to detect if the retina is healthy or diseased. It is painless and effective and does not require that your cat be sedated.
What can I do about Progressive Retinal Atrophy? Unfortunately, no effective treatment is available to slow down or reverse this condition. Total blindness can occur in the later stages of this disease. However, you can take steps in your home to make it safer for a cat that is experiencing diminishing eyesight. Position night lights in rooms, provide gates and other barriers to keep your cat from falling through spaces in balconies or stairways and do not re-arrange the furniture. In addition, keep cat essentials – food and water bowls plus litter boxes – in specific places so your cat can easily find them. Blind cats can and do live full productive lives when kept indoors. They learn to use their sense of hearing and smell to compensate for their fading sense of sight.
Is there anything I can do to prevent my cat from getting Progressive Retinal Atrophy? Recognize that genetics plays a big factor in this disease. If you wish to get a purebred cat, work with reputable breeders who took the necessary steps to identify genetic carriers of PRA and remove them from the breeding pool. If you discover your purebred cat has PRA, contact your breeder to prevent this trait from being passed on. DNA research is underway to develop tests that identify the genes responsible for PRA in cats.
Are there certain breeds that get Progressive Retinal Atrophy more often? Yes. Abyssinians are most susceptible as PRA is passed on as a dominant trait. Persians and Siamese are two other breeds who are also at risk, but PRA can affect mixed breed cats.