What is SARDs?
Sudden Acquired Retinal Degeneration (SARD) is a retinal disease causing blindness over a period of days to weeks. The onset of blindness can be very sudden and occur virtually overnight.
The blindness results from a degeneration of the visual cells in the retina (rods and cone or photoreceptors).
What are the signs of SARDs?
The eyes may appear normal but the animal is blind. The pupils may have abnormal responses to light. Animals may have only blindness or other additional signs like increased drinking, urination and appetite.
What causes SARDs?
The exact cause of SARD is unknown. Theories for the cause of the disease include toxins and autoimmune disorders but none of these have been proven.
How is SARDs diagnosed?
SARD animals may have a normal eye exam or show subtle signs of the disease. The diagnosis is made from an electroretinogram (ERG) that evaluates retinal function.
Brain diseases and optic nerve diseases can appear just like SARDs by causing fairly sudden blindness, and an ERG can distinguish between these neurological diseases and SARDs. Knowing the cause of blindness is important for the long term expectations, treatment options and prognosis for life.
With SARD, the ERG will register no function and be flat. With optic nerve or brain disease, the ERG will be normal.
How is SARDs treated?
SARD has been treated experimentally at Iowa State. The other signs of increased drinking and urination usually improve with time. About 1/3 of the dogs with SARD also have another hormonal disease (hyperadrenocorticism) that may require additional tests and medical treatment.
Dogs that are blind can still have a wonderful quality of life!
SARD takes vision away so quickly that dogs will have an adjustment period. In the beginning, dogs will bump objects, act confused and be more clingy. In the long run, most dogs adjust well to their loss of vision, especially if they are of a smaller breed. Dogs have many other senses like their hearing and smell that far exceed our own.