- Type Disease
Eye
- Name
Collie Eye Anomaly (CEA)
- Abbreviation
CEAx
- Description
CEA is a disorder of the deep structures of the eye that affects collie breeds around the world. The four main changes are:\n\ninadequate development of the choroid, a thin layer of blood vessels that delivers oxygen and nutrients to the retina (called hypoplasia of the choroid or chorioretinal dysplasia);\ncoloboma - a cleft or defect of the optic disc or adjacent areas;\nstaphyloma - an area of thinning in the sclera which is adjacent to the choroid; and\nretinal detachment with or without hemorrhage - a complication associated with the other defects.\nIn its mildest form, there are minor changes in the choroid which will have little effect on sight. About 25 per cent of dogs with CEA have colobomas/staphylomas as well as choroidal hypoplasia. Retinal detachments occur in approximately seven per cent of dogs with CEA. Total retinal detachment will cause blindness.
- How Transferred
Inheritance is autosomal recessive with variable expression and pleomorphic (meaning that there is a wide range in clinical expression of the defect).
- What to Look for
Many dogs will have apparently normal vision unless retinal detachment with or without hemorrhage occurs, causing blindness in the affected eye. Retinal detachments are often one-sided and generally occur before 2 years of age.
- Diagnosis
Your veterinarian will be able to see the abnormalities in the back of the eye with an ophthalmoscope.
- Treatment
There is no treatment.
- Veterinarian Information
Choroidal hypoplasia - appears as an area lateral (temporal) to the optic disc with reduction or absence of pigment so that the underlying choroidal vasculature is seen; the choroidal vessels may be reduced in number and of abnormal shape; may see underlying white sclera. Once the retina changes to its adult color (about 3 months of ages), the normal pigment in the retina may mask the changes in the choroid (so-called go normal)\n Coloboma - appears as an excavation of the optic disc surface and sometimes adjacent ocular fundus\n Retinal complications - detachment with or without hemorrhage
- Breeding Considerations
Minor lesions may not be detectable by ophthalmoscope after 3 months of age, so collies intended for breeding programs should be examined early at 5-6 weeks of age. Even dogs with minor lesions (mild choroidal hypoplasia) should not be bred because their offspring may be affected with more serious forms of the disorder.\n\nBecause of the potential for serious eye disease with this trait, neither affected dogs, their parents, or their offspring should be used for breeding. Siblings of affected dogs should not be used either, unless eye exams before 3 months of age demonstrate that they are unaffected.
- Known Breeds Affected
Border collie\nCollie (rough and smooth)\nShetland sheepdog\nAustralian shepherd
