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Genetic ocular problems: what breeders know that you need to know (Proceedings)

May 01, 2011

Most conditions in ophthalmology have a strong connection to genetics. Often a diagnosis can be made by knowing only the breed, age, and presenting complaint. There are some conditions that are common to one breed but rarely if ever seen in another. This review will list the most notable genetic conditions for each region of the eye.

Eyelid

Entropion:

Inversion of the eyelid margin such that the eyelid cilia contact the cornea causing irritation.

Chow Chow, Shar Pei, Cocker Spaniel, Retrievers, Poodles

Ectropion:

Eversion of the eyelid such that the margin does not contact the cornea. Giant breeds.

St. Bernard, Bloodhound, Great Dane, Newfoundland, Bull Mastiff

Distichiasis:

Cilia emerging from the Meibomian gland duct openings. Often fine hairs that cause no clinical problems

Cocker Spaniel, Miniature Dachshund, Bulldog, Yorkshire Terrier

Trichiasis:

Normal eyelid cilia that are deviated abnormally toward the cornea

Cocker Spaniel, Shi Tzu, Japanese Chin

Globe and surrounding tissues

Microphthalmia:

Globe of an abnormally small size. Often they are still visual, but may be associated with other congenital anomalies.

Australian Shepherd, Collie, Miniature Schnauzer, Shetland Sheepdog

Dermoid:

Ectopic patch of haired skin growing on the cornea or conjunctiva. Although it looks unusual, it poses no health risk, is non-progressive, and is easily treatable with surgery.

Dachshunds, Doberman Pincer, Dalmatian, St. Bernard, German Shepherd

Cherry Eye:

Prolapse of the third eyelid gland due to abnormal connective tissue attachments. Non-painful and can lead to dry eye if the gland is not replaced.

Bulldog, Cocker Spaniel, Neapolitan Mastiff

Cornea and sclera

Corneal Dystrophy:

White cholesterol or calcium deposits in the cornea. Typically cause no pain or vision loss. Treatment is usually not needed.

Siberian Husky, Shetland Sheepdog, Beagle, Collie, Cavalier King Charles

Corneal Endothelial Dystrophy:

Progressive blue corneal edema resulting from loss of corneal endothelial cells. The corneas appear blue, but there is no pain and vision is unaffected except for severe cases.

Boston Terrier, Longhaired Dachshund, Chihuahua, Chow Chow

Microcornea:

Normal globe size but abnormally small cornea.

Australian Shepherd, Miniature Schnauzer, Miniature and Toy Poodle, St. Bernard

Non-Healing Ulcers:

Condition affecting the ability of corneal epithelial cells to attach to the underlying stroma. Typically occur spontaneously and rarely seen in dogs less than 7 years of age.

Boxer, Retrievers, Samoyed, Poodles

Pannus:

Autoimmune condition involving abnormal vascularization and pigmentation of the cornea.

German Shepherd, Greyhound, Australian Shepherd, Cattle Dogs, Siberian Husky