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Entropion
Entropion (inward rolling of the eyelid onto the eye) usually affects the lower eyelid. It is most common in dogs less than one year of age. Many of the cases that I see have overly long lower eyelids. Entropion can cause irritation to the eye, and in severe cases ulceration of the cornea.
Surgery is required. In young pups a temporary stitch can be used to evert the eyelids away from the eye. Most cases require excision of skin to evert the eyelids, and in some cases also require eyelid shortening. I use the operating microscope and fine sutures to minimise the chance of scar tissue forming.
A number of genes are involved in the inheritance of entropion. Other factors such as head conformation, eye socket shape and depth, and environment are involved. It is suggested that affected animals should not be used in a breeding program.
Persistent Pupillary Membrane (PPMs)
The mildest form of PPMs affect many Goldens. These are small strands of iris tissue that run across the surface of the iris, and they do not cause clinical signs. I do not feel that the PPMs are of concern unless they are severe.
Imperforate Tear Punctum
In some cases the lower tear duct opening (punctum) in the eyelid does not form. Affected dogs present with watery eye as a pup. Using the operating microscope a new tear duct opening is created. The mode of inheritance is unclear, but there is a distinct familial pattern. This problem seems to be increasing in incidence.
Cataracts
Any opacity in the lens is called a cataract. There are many causes for cataracts, some of which are inherited. If the cataracts are in both eyes and they mature, the animal may become blind. Surgery is available in some cases.
The posterior polar subcapsular cataract (PPS) is better known as the star cataract. It is usually in both eyes and becomes apparently between 6 to 18 months of age. Some dogs may develop this problem as late as 6 to 7 years of age. The cataract may be slowly progressive, but rarely interferes with vision. It is advised not to breed from affected animals as matings with affected dogs have produced litters of blind pups.
Another type of cataract is found in Goldens. This one affects the front of the lens from 3 to 6 years of age. It only rarely causes blindness.
In the last 12 months we have been seeing a 'new' type of cataract in Goldens. This is a juvenile cataract, and affected dogs are usually less than 18 months of age. Most of these cataracts cause problems with vision. The centre (nucleus) of the lens is affected, and surgery may be required. In some cases atropine eye drops can be used to dilate the pupil to allow the pup to see around the cataract.
Persistent Hyaloid Artery
This is a minor problem, and is unlikely to be inherited. It may be associated with a cataract at the back of the lens.
Progressive Retinal Atrophy
There are two types of PRA in Goldens, one an early onset within the first two years of life, and the other occurring between 5 to 8 years of age. Affected dogs have night blindness; progressing to day blindness and in the later stage cataracts may develop. I have now seen 2 cases of PRA in Goldens. A blood test for PRA is being developed for use in Melbourne.
Glaucoma
Golden Retrievers do not seem to be at great risk of glaucoma compared to other breeds such as Bassets or Cocker Spaniels. Affected eyes quickly lose vision and become painful. The eye may be red or blue and have a mid-dilated non-responsive pupil.
Urgent specialist treatment is recommended if you are suspicious of glaucoma. At Animal Eye care we are now using the state of the art Diode Laser to treat canine glaucoma. This treatment seems to give us the best chance of controlling the glaucoma and saving vision as well.
Distichiasis
Distichia (extra eyelashes) grow from glands in the eyelid edge onto the cornea. Depending on a number of factors extra eyelashes may or may not cause irritation to the eyes. I have seen eyes lost because of extra eyelashes.
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