Collie eye anomaly, also known as scleral ectasia syndrome and collie ectasia syndrome, is an inherited
condition in which certain tissues
in the eye of the fetus did not transform normally, resulting in various eye abnormalities.
Originally discovered in the Collie breed, Collie eye anomaly also affects other breeds including Australian Sheepdogs, Border Collies, and Shetland Sheepdogs. In the Shetland Sheepdogs the condition is commonly referred to as 'Sheltie eye.' Collie eye and Sheltie eye are inherited, and as many as 90 percent of all Collies in the United States are said to be affected to some degree.
In this condition, areas of tissue in the fetus did not transform as they should have.
What are the symptoms?
In severe cases, vision may be greatly impaired, however, in most instances, the lesions can only be identified by an exam with an ophthalmoscope. Collie eye anomaly is a condition which includes several eye defects. A dog with Collie eye anomaly may have a detached retina, optic nerve abnormalities, and/or a loss of retinal cells.
What are the risks?
Vision is always impaired, but the extent depends on the severity of the defects. It is inherited and should be selected against in any breeding program. Exams and certification by a veterinary ophthalmologist should be conducted in all animals of affected breeds who may be used for breeding. These exams can be done as early as 6-8 weeks of age.
What is the management?
There is no treatment to eliminate Collie eye anomaly. Breeders typically select against this condition by having puppies examined at a very young age (six weeks), then periodically afterwards. Veterinarians can detect lesions early on in cases of which the retina has not developed correctly or lacks normal pigmentation. Small lesions, however, may become pigmented with age. Breeders refer to puppies with disappearing lesions as 'go-normals.' Despite the term 'go-normal,' these puppies are not normal and should not be bred.