Goniodysplasia, Goniodysgenesis
Goniodysgenesis is an abnormal fluid drainage angle development in the eye. This is presumed to be an inherited, congenital ocular deformity of the pectinate ligament, fibrous band radiating from the base of the iris and inserting into the inner surface of the cornea as the entrance of the aqueous drainage system.
The condition is characterized by inadequate and/or very small drainage openings, resulting in a potential obstruction of outflow of eye fluid. The outflow often appears to remain undisturbed for a long time. In a low percentage of cases the outflow is impaired, resulting in hereditary primary glaucoma in dogs. It invariably affects both eyes, although the two eyes are not usually affected simultaneously.
Breeds Affected by Goniodysplasia
Affected breeds include Basset Hound, Bouvier des Flandres, Samoyed, Great Dane, Siberian Husky, retrievers, terriers (Welsh terrier and Dandie Dinmont terrier) and spaniels (American Cocker and Welsh).
Goniodysplasia & Glaucoma
The strong and significant link among goniodysgenesis and glaucoma and the significant heritability of goniodysgenesis suggests that glaucoma may be heritable in Great Danes. If so, glaucoma can be controlled by breeding only from sires and dams with a minimum degree of goniodysgenesis.
In case of primary glaucoma, both surgical and medical treatments may be needed. Long term management may include prophylactic treatment of the second eye before any clinical signs of intraocular pressure are present.
References:
1. Notes on Veterinary Ophthalmology. Sheila M. Crispin
2. Relationship of the degree of goniodysgenesis and other ocular measurements to glaucoma in Great Danes. Wood JL, Lakhani KH, Mason IK, Barnett KC.
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