EYE PROBLEMS OF THE SIBERIAN HUSKY

  • ENTROPION - A conformational defect resulting in an "in-rolling" of one or both of the eyelids which may cause ocular irritation. It is likely that entropion is influenced by several genes (polygenic), defining the skin and other structures which make up the eyelids, the amount and weight of the skin covering the head and face, the orbital contents, and the conformation of the skull.

  • CORNEAL DYSTROPHY - A non-inflammatory corneal opacity (white to gray) present in one or more of the corneal layers' usually inherited and bilateral.

  • GLAUCOMA - An elevation of intraocular pressure (IOP) which, when sustained, causes intraocular damage resulting in blindness. The elevated IOP occurs because the fluid cannot leave through the iridocorneal angle. Diagnosis and classification of glaucoma requires measurement of IOP (tonometry) and examination of the irodocorneal angle (gonioscopy). Neither of these tests are part of a routine breed eye screening exam.

  • UVEODERMATOLOGIC SYNDROME - A syndrome of severe uveitis combined with dermal depigmentation. Secondary glaucoma and/or retinal detachment are frequent complications of this disease. Seen most commonly in the Akita, Samoyed, Siberian Husky breeds. Adhesions between the iris and lens (posterior synechia) and the peripheral iris and cornea (peripheral anterior synechia) develop rapidly. Other complications include cataract development, retinal degeneration, retinal separation or detachment, optic disc atrophy and secondary glaucoma. Poliosis and/or vitiligo are generally later developments. This disorder is thought to represent an immunemeidated reaction to uveal and epidermal pigment cells.

  • UVEITIS (WITHOUT VITILIGO OR POLIOSIS) - An inflammation of the uveal tract (iris, ciliary body, choroid). May be caused by infectious agents or may be immune-mediated. There are syndromes of immune-mediated uveitis associated with facial skin depigmentation (uveodermatologic syndrome). With any form of uveitis, adhesions may develop between the iris and lens (posterior synechia) and the peripheral iris and cornea (peripheral anterior synechia). Other complications include secondary cataract and glaucoma. Some veterinary ophthalmologists feel the uveitis without skin or hair depigmentation may occur with greater frequency in the Siberian Husky than in most other breeds. At this time, adequate documentation is lacking.

  • CATARACT - A partial or complete opacitiy of the lens and/or its capsule. In cases where cataracts are complete and affect both eyes, blindness results. The prudent approach is to assume cataracts to be hereditary except in cases known to be associated with trauma, other causes of ocular inflammation, specific metabolic diseases, persistent pupillary membrane, persistent hyaloid or nutritional deficiencies. Cataracts may involve the lens completely (diffuse) or in a localized region.

    In the Siberian husky, cataracts begin in the axial posterior cortex at approximately one year of age. Progression is variable and vision impairment may occur. In cases with rapid progresion, secondary lens-induced uveitis and glaucoma may be associated with partial cataract resorption.

  • RETINAL ATROPHY - A degenerative disease of the retinal visual cells which progresses to blindness. This abnormality, also known as progressive retinal atrophy or PRA, may be detected by electroretinogram (not part of a routine eye screening examination) before it is apparent clinially. In the Siberian Husky, one form of PRA is inherited as a sex-linked trait.