Corneal dystrophy

Encyclopedia : C : CO : COR : Corneal dystrophy

A corneal dystrophy is a noninflammatory, inherited, bilateral condition affecting the transparent front part of the eye called the cornea. It is commonly seen in dogs. It appears as grayish white lines, circles, or clouding of the cornea. Corneal dystrophy can also have a crystalline appearance. It is caused by an accumulation of lipids or cholesterol crystals.

Corneal dystrophy in a dog

Corneal dystrophy does not usually significantly affect vision and therefore does not require treatment. It can, however, rarely cause corneal ulceration, especially with epithelial dystrophy. It is rare in cats.

Contents

1 Classification
2 Commonly affected breeds
3 Corneal endothelial dystrophy
4 See also
5 References
6 External links

Classification

Corneal dystrophies are commonly subdivided as anterior, stromal, or posterior according to the part of the cornea affected[link][link].

Commonly affected breeds

Many breeds are affected by corneal dystrophy with many different appearances. These breeds most commonly have these criteria.

Afghan Hound
Airedale Terrier - occurs at 4 to 12 months of age in the central cornea. It is progressive and can cause decreased vision.
Alaskan Malamute - occurs at greater than two years of age in the central cornea.
Beagle - has a nebular, race track, or arcing appearance.
Bearded Collie - occurs at greater than one year of age in the lateral or central cornea and can affect just one eye.
Bichon Frise - occurs at greater than two years of age in the inferior or central cornea.
Cavalier King Charles Spaniel - occurs at two to four years of age in the central cornea.
American Cocker Spaniel
Rough Collie - occurs at one to four years of age in the inferior or central cornea.
English Toy Spaniel - occurs at two to five years of age and has a crystalline, circular appearance.
German Shepherd Dog - occurs at one to six years of age and is usually oval.
Golden Retriever - occurs at less than two years of age and can be progressive.
Italian Greyhound - occurs in young dogs and is focal.
Lhasa Apso - oval appearance.
Mastiff - oval appearance.
Miniature Pinscher - occurs at one to two years of age and is oval.
Norwich Terrier - peripheral cornea.
Pembroke Welsh Corgi - occurs in young dogs and can include blood vessels and pigmentation.
Pointer - gray, hazy ring.
Poodle - occurs at greater than one year of age.
Samoyed - oocurs at six months to two years of age and is gray and round.
Shetland Sheepdog - occurs at two to four years of age as multiple gray/white rings. It can develop into a corneal ulcer.
Siberian Husky - occurs at five months to two years of age and is gray and oval.
Weimaraner - Occurs at one to eight years of age in the central cornea.
Whippet - occurs at three to five years of age in the central cornea.

Corneal endothelial dystrophy

Corneal endothelial dystrophy affects the inner layer of the corneal, the endothelium. Leakage of fluid into the cornea causes edema, causing a bluish appearance. This will eventually involve the whole cornea. Hyperosmotic agents are sometimes used topically for treatment. Bad cases may require a corneal transplant. The most commonly affected breeds are the Boston Terrier, Chihuahua, and Dachshund. The disease is similar to Fuch's dystrophy in humans.

References

External links