EYE PROBLEMS

by: Internal Article

The eye is very complex organ with many different, very important parts.  In order for an animal to see perfectly, the parts must all be healthy and functional.  Some damage/change can occur in dogs, however, without a significant reduction in their visual acuity or ability.  There are a large number of diseases or defects seen in the eyes of dogs, some of which are breed specific and others that are seen in all breeds and cross-breeds.  Some are proven to be hereditary, some seem to run in families but a definite hereditary basis has not been established (but is highly likely), others are clearly not hereditary but are secondary to other conditions (such as other disease or just old age) or to some injury, and there are also some conditions where no-one yet knows what exactly is the primary cause, hereditary or environmental or "just one of those things."  To complicate matters further, some conditions that look (at least at first glance) the same or that have the same generic name may be clearly hereditary in some cases but not in others.  It is becoming increasingly apparent that many diseases and malformations of the body do have a genetic basis, ranging from a polygenic inherited predisposition, which then needs triggering environmental factors to be seen, to a simple single gene mutation that results in an "all or nothing" effect.

Diagram of The Canine Eye

CERF or other equivalent National schemes have, to date, reported the following conditions in Malamutes.
 (Some are rare, and some are relatively frequently seen.  Note that not all are hereditary.):

  • Cataract (any lens opacity is, technically, a cataract, whether significant or not)
  • Corneal Dystrophy
  • Distichiasis
  • Dry eye
  • Ectopic cilia
  • Ectropion
  • Entropion
  • Glaucoma
  • Iris cysts
  • Lens luxation/subluxation
  • Optic nerve coloboma
  • Optic nerve hypoplasia/micropapilla
  • Persistant hyaloid artery (PHA)
  • Persistent pupillary membranes (PPM)
  • Persistant hyperplastic primary vitreous/ persistent hyperplastic tunica vasculosa lentis (PHPV/PTVL)
  • Progressive retinal atrophy, generalized (GPRA)
  • Retinal detachment
  • Retinal dysplasia

The following are conditions that are known to occur in the Alaskan Malamute but are not recorded under CERF or other National schemes:

Hemeralopia (dayblindness)
Recurrent/indolent corneal ulceration

From 1991 to 1999, under the CERF scheme, just over 21% of Malamutes examined had some visible eye changes recorded.  Check under the individual conditions for their prevalence (according to CERF), as well as a description of the defect/disease and a commentary of the latest understanding of the hereditary (or otherwise) nature of the condition in dogs and more specifically (where possible) in the Alaskan malamute.

Please follow these links for more detailed information for specific problems.  We will add more information as it becomes available:


Cataracts
Dayblindness (hemeralopia)
Distichiasis
Entropion
Glaucoma
Progressive Retinal Atrophy

Hereditary Eye Diseases in Dogs: (PDF) Pamphlet

CREDITS:

Internal Article: Sourced primarily contributed by AMCA member, Karyn Colman.

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