sudden acquired retinal degeneration syndrome
Blindness in dogs is not uncommon, and dogs have proven time and time again that they can easily adapt to this lifestyle, especially when blindness is gradual. In fact, I think a diagnosis of blindness is sometimes harder on the owner than it is on the dog! But there are times when blindness occurs acutely, and it is these cases that dogs (and their owners) need a little more help adjusting to life without sight.
Sudden acquired retinal degeneration syndrome, or SARDS, is one such condition—blindness occurs very rapidly. Sometimes it seems to be almost instantaneous, but even in SARDS cases that are drawn out, we’re still talking about blindness that develops in a few days, rather than the vision loss we see over time with progressive retinal degeneration.
The retina lines the back of the eye and performs the very important job of detecting light and sending images to the brain. As the name implies, sudden acquired retinal degeneration syndrome causes blindness due to degeneration and dysfunction of the retina. The blindness caused by SARDS is rapid and irreversible.
The underlying cause of SARDS is not yet known. We do know that it tends to occur in middle-aged to older dogs, and that some breeds are more likely to be affected than others, including:
Of course, the most important sign of SARDS is sudden onset blindness. You may also notice that your dog has dilated pupils. Dogs may be disoriented and have trouble finding their way around without bumping into walls and furniture. Alternatively, newly blind dogs may be anxious and wary to move about.
Other signs that sometimes correlate with SARDS are lethargy, weight gain/obesity, panting, increased appetite, and increased water intake with increased urination. These signs are very similar to those we see in dogs with hyperadrenocorticism (or Cushing’s disease), and they may precede or follow blindness.
Your veterinarian will take a thorough history and will examine your pet’s eyes. Typically, the eyes and even the retina will appear normal initially in dogs with SARDS. Your veterinarian will probably want to perform some blood work to check for underlying metabolic disease, especially Cushing’s disease. It is likely that your pet will be referred to an ophthalmologist for final diagnosis of SARDS, however, as an electroretinogram (ERG) is needed to check retinal function.
Blindness caused by SARDS is irreversible. There is no treatment. But the diagnosis of SARDS following sudden blindness is actually good news! Aside from blindness, there are no other long term effects on your pet’s health. The same cannot be said for other reasons of sudden blindness. If your dog had concurrent symptoms like increased hunger, thirst and urination, you can expect those to abate with time.
All that you and your pet need to do is adjust to the blindness. Your dog will amaze you with her ability to do just that, so sit back, relax, and don’t rearrange the furniture!