Multifocal Retinal Dysplasia in Dogs

Multifocal Retinal Dysplasia or MRD, is a hereditary condition that can seriously affect a dog's vision and in a worst-case scenario could lead them losing their sight altogether. There are certain breeds that seem to be more predisposed to inheriting the condition than others and as such the British Veterinary Association strongly advises that all breeds known to suffer from Multifocal Retinal Dysplasia be eye tested annually before being used as stud dogs.

The Different Types of MRD

There are three types of the condition, but all three are serious eye disorders that dogs can pass on to their offspring. These are as follows:

• Type 1: Retinal Folds or Rosettes. This is the mildest form of the condition and it is where retinal folds or rosettes form in a dog’s eye or eyes. In some instances, these disappear as a dog matures, but at the other end of the scale, the problem could get worse too
• Type 2: Geographical changes: this type of the condition see the retina become thinner and having strange irregular shaped areas. It is often connected to another eye condition called retinal detachment. When dogs inherit this type of Multifocal retinal dysplasia, their vision may be impaired to a certain degree or they could be totally blind, but either way, this is for the remainder of their lives
• Type 3: Retinal Detachment. This is the most severe form of the condition where the retina becomes totally detached which results in total blindness. The onset of the condition can be sudden which is extremely distressing for both the owners and their dogs.

Research suggests that the condition is linked to other forms of dysplasia and this includes both hip and elbow dysplasia. The one constant in all three types of the condition is that symptoms are always present when puppies are first born.

Breeds More Predisposed to Multifocal Retinal Dysplasia

As previously mentioned, there are certain breeds that appear to be more predisposed to inheriting this eye disorder than others and this includes the following:

• Cavalier King Charles Spaniel
• Rough Collie
• Labrador Retriever
• Utonagan - although the condition has only been found in one line to date (November 2016)

The Causes

As previously mentioned, it is a hereditary condition, but there have been cases of dogs developing the disorder when puppies were exposed to certain toxins while still in their mother's womb. There is some thought that a deficiency in Vitamin D may also play a part in a dog developing the disorder.

Diagnosing the Condition

Because the condition can be easily missed during a routine eye check-up, it is extremely important for dogs known to be predisposed to be subjected to a full eye screen test that's available through the BVA. The test is carried out by a qualified Ophthalmologist and at the same time, they would check for any other congenital and hereditary eye disorders.

Treatment Options

For the moment, there are no treatment options for the condition nor is there a cure. It can be very distressing when a dog suddenly goes blind, but they do adapt quickly with their other senses becoming more acute and therefore compensating for their lack of vision.