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Collie Eye Anomaly (Optic Nerve Colobomas) in Dogs

What to Watch For

Optic nerve colobomas, whether inherited as CEA or acquired congenitally via embryologic aberration, are present at birth and do not progress.

Affected dogs’ vision will be altered to varying degrees (generally mildly and sometimes not at all). Hence, some puppies will never be diagnosed and will continue to pass down the genetic trait associated with either CEA or embryologic anomaly.

Diagnosis for CEA in Dogs

Optic nerve colobomas are diagnosed via fundoscopic examination (observing the back of the eye with a lens). The coloboma typically appears as a misshapen optic disc, usually in the area located at 6 o’clock.

Diagnosis usually occurs either in the course of normal puppy evaluation, because vision impairment is suspected or when the puppy is of a CEA-prone breed. For CEA breeds, genetic testing is now available to determine whether dogs carry the genetic trait that may lead to optic nerve colobomas.

Treatment of CEA in Dogs

No treatment is available for this condition.

Prevention of CEA

Preventing optic nerve colobomas is best achieved through CEA testing of all susceptible breeding animals. Affected and carrier individuals should be removed from the breeding pool. Additionally, any dog with a non-CEA related optic nerve coloboma should not be bred.

References for Collie Eye Anomaly (Optic Nerve Colobomas)