Retinal dysplasia (RD) is abnormal development of the retina. It is seen in a number of breeds at Animal Eye Care. Most commonly we diagnose retinal dysplasia when we are examining breeding dogs prior to breeding as part of the Australian Canine Eye Scheme (ACES).
Causes
Caption: This is a picture of a normal retina in a dog.
The colour can vary depending on the age and the breed.
There are various causes for retinal dysplasia, the most common cause being inherited. RD may also result from viral infections, and exposure to toxins. In some cases retinal folds may be seen in young puppies around 6 to 8 weeks of age. It is thought that this is a growth related problem, in that the sclera (coat of the eyeball) and the retina are growing at different rates. Within 4 to 6 weeks the retinal folds resolve as the retina and sclera (coat of the eyeball) are then growing at the same rate. This is not thought to be inherited. However dogs can have lots of retinal folds and this may be a sign of RD. In breeds that are affected with RD, growth related retinal folds may confuse the diagnosis of inherited RD. In some cases we recheck these puppies later on once they has finished growing to see if the retinal folds have disappeared. RD will not disappear.
Retinal dysplasia is seen most commonly at Animal Eye Care in Labradors, Cavaliers, Golden Retrievers, and Springer Spaniels. Other breeds affected include the Bedlington and Sealyham Terriers, Beagle, Cocker Spaniels both English and American, Yorkshire Terrier, Akita, Afghan Hound, Doberman Pinscher, Old English Sheepdog, and Rottweilers. If you see RD in these breeds it can be assumed that the RD is inherited.
You can see in the image on the right there are lots of small dark lesions in this retina. Each of these dark lesions is where the retina has not developed normally. As there are many lesions this is called MRD – multifocal retinal dysplasia. Springer Spaniels normally have the orange color to the retina.
Clinical Signs
Most dogs with mild RD do not show any clinical signs. Vision is essentially normal, despite the RD causing small blind spots. Some owners of retrieving dogs report that their dogs with RD or MRD do not trial as well as normal dogs.
Importantly dogs affected with multifocal retinal dysplasia (MRD) such as the Cavalier, Labrador, Golden Retriever and the Springer Spaniel, are at risk of retinal detachment resulting in vision loss.
