An Overview – Sudden Acquired Retinal Degeneration Syndrome (SARDS) in Dogs
Definition
Sudden Acquired Retinal Degeneration Syndrome (SARDS) is a disease categorized by abrupt loss of sight in dogs. This illness affects the retina which is that part of the eye accountable for sending visual signals to the brain for processing.
There is ensuing degradation and degeneration of the retina that could even lead to further complications.
Apart from the sudden loss of vision, most dog owners also notice enlarged pupils, increased appetite for food, and thirst.
The sickness is characterized by sudden onset of visual impairment because of loss of photoreceptor abilities, extinguished electroretinogram with an initially normal-appearing ocular fundus, and mydriatic drug pupils that respond very slowly to bright white light, do not respond to the red light but are responsive to stimulation with blue light.
Cause
The underlying cause of Sudden Acquired Retinal Degeneration Syndrome (SARDS) in dogs is unfortunately not yet known; however, laboratories around the globe are working tirelessly on research to find the cause. There are several propositions for this syndrome. They include endocrine disorders, toxicity, infection, autoimmune disease, neoplasia, etc.
Diagnosis
In all patients with sudden vision loss, an electroretinogram (ERG) is recommended. This test serves as a tool for assessing the functionality of the retina. A negative result provides a definitive diagnosis of SARDS in dogs.
An ERG is a non-invasive test that involves placing a specialized contact lens on the surface of eyes that have been numbed with topical anesthetic drops.
Some pets need tranquilization to scale back movement that may have an effect on the results. Once the eyes have acclimatized, a standardized set of light flashes are created to stimulate the retina’s photoreceptors.
Breed Specific
Sudden Acquired Retinal Degeneration Syndrome typically affects middle‐aged to elderly and often moderately overweight dogs. It is frequently seen in old female castrated adult dogs as between 60 and 90% of affected dogs are female. The reported mean or median ages of dogs affected by SARDS range from 7 to 10 years. No breed is thought to inherit the condition; however, some breeds seem to be more prone than others.
Among them are dachshunds, pug, Brittany, bichon frisé, and miniature schnauzers. Affected animals are generally healthy, however as stated above, some dogs might have a recent history of unexplained weight gain, pronounced consumption of water and/or inflated urination, lethargy, pacing, panting, pronounced craving.
Blood work is usually recommended to categorically rule out possible systemic problems.
SARDS Treatment and management
It is generally believed that vision loss with SARDS is permanent and that there is no SARDS treatment that can prevent or reverse the blindness related to it.
On the bright side, SARDS does not come with pain and thus the life expectancy of the dogs is not reduced. Most dogs take within a few weeks or months to adapt very well to this sudden loss of sight.
Conclusion
The blindness of the dog should not be a reason why a dog owner is considering euthanasia. Hopefully, in the nearest future, research and clinical trials will someday reveal a treatment or cure for SARDS.
The vet doctors and nurses can provide counseling to enable both the dog and the owner to return to the happy life they had before blindness occurred, keeping in mind this change is even tougher on the owner emotionally than it is for the dog.