Collie Eye Anomaly in Dogs

Collie eye anomaly is also sometimes referred to as collie eye defect, is an inherited congenital condition. In order to absorb light and receive an adequate blood supply, the eye needs help from the choroid, a collection of blood vessels within a layer of tissue located under the retina.

When these chromosomes that determine the development of the eyes are mutated, the choroid becomes underdeveloped. This disease can lead to blindness if it is severe enough since the retina does not receive proper blood flow or becomes detached.

This condition is known to occur in breeds such as Collies (smooth and rough collies), Shetland Sheepdogs, Australian Shepherds, Border Collies, Lancashire Heelers, and Nova Scotia Duck Tolling Retrievers. Frequency is high in Collies and Shetland Sheepdogs, and low in Border Collies.

CEA affected puppies generally appear normal because very few have defects that seriously impair vision. Those defects are within the eye and cannot be detected without special instruments. So diagnosis can only be made by a veterinary ophthalmologist or with a DNA test. While coloboma and retinal detachment will be identified on exam, CH may not be apparent in puppies over 6-8 weeks of age because it is can be obscured as the pigment develops in the back of the eye, a condition called masked affected.

If you see signs of this condition in your dog, then you should consult your veterinarian right away so they can treat it.

Causes of Collie Eye Anomaly in Dogs

The cause of collie eye anomaly is a defect in chromosome. It only occurs in animals that have a parent, or parents, that carry the genetic mutation. The parents may not be affected by the mutation, and may therefore not have been diagnosed with the abnormality. Their offspring on the other hand can be affected, especially when both parents carry the mutation. It is also suspected that other genes may be involved, which would explain why the disorder is severe in some collies and so mild that it causes no symptoms in another.

Symptoms of Collie Eye Anomaly in Dogs

The signs and symptoms of CEA vary from dog to dog. For some dogs, it’s not so bad, while for others, it can lead to vision loss. This is due to holes or pits in different layers of the eye. Depending on the size and location of the holes, vision loss can be slight or total. CEA can also lead to retinal detachment.

CEA may be associated with several, more obvious abnormalities in the eye. “Microphthalmia” describes eyeballs that are smaller than normal. “Enophthalmia” describes eyeballs that are sunken deep into the eye sockets. Both of these abnormalities can be associated with CEA.

Treatment of Collie Eye Anomaly in Dogs

In some instances, surgery is available to prevent retinal detachment if that is a concern for your dog’s specific symptoms of CEA.

In general though, collie eye anomaly is not considered to be treatable. Some dogs may not fully lose their vision while others do. It is important to remember that dogs adjust well to losing their vision and can still lead very happy lives.