Most people normally associate the presence of cataracts with old age in humans. But do you know that cataracts can also occur in pets such as dogs?
Although dogs of all types of breeds can develop cataracts at any age, dogs with diabetes are certainly at a higher risk of developing cataracts. Cataracts are also more commonly observed in breeds such as Poodles and American Cocker Spaniels.
What exactly is a cataract?
A cataract is an abnormality in the lens of the eye, in which the lens becomes opaque. In order to function normally, a lens needs to be clear, so that it can focus light from the outside onto the retina without scattering it. The presence of cataracts results in attenuation of some of this light, resulting in blurred vision. The severity of cataracts can vary, with the most severe ones allowing very little light to reach the retina.
What does a cataract look like?
The appearance of cataracts varies, depending on the cause and the severity of the condition. They could make the dog’s eyes look hazy, have a sheen or make them look like cracked ice. Normally, cataracts start off as small defects, and these may not be easily noticeable. With time, they tend to expand, becoming more visible to the pet owner. The rate of growth is not predictable, but studies have shown that it’s much faster in younger pets. It is also possible for a dog to develop cataracts on both eyes, in which case the resulting visual impairment can be severe.
What are some of the predisposing factors?
A number of factors have been shown to either directly cause cataracts or increase the chances of a dog acquiring them. Some of these include:
- Heredity: If the dog has parents that had cataracts, it has a higher chance of developing the defect during its lifetime.
- Inflammation: An inflammatory reaction involving the eyes can result in the formation of cataracts. This can also be due to trauma to the eye.
- Diabetes: This is one of the most significant causes of cataracts in both humans and dogs. Dogs that are diagnosed with diabetes have an 80% chance of developing cataracts within 18 months of the diagnosis.
- Poor nutrition: This is an uncommon cause of cataracts, but it has been reported in a handful of cases.
Do note that in numerous cases, there is no identifiable cause or risk factor for cataracts in the dog.
How is the condition diagnosed?
The diagnosis of cataracts in dogs involves inspecting both the retina and the lens. If the cataracts are minor, the area behind the lens can be inspected using an ophthalmoscope. If not, an electroretinogram will be used. Cataract surgery will be recommended when the retina is shown to be healthy, which means that removal of the cataract will improve vision.
Once the presence of the cataract is established, the only feasible treatment for it is through a cataract surgery. Medical treatments have not been shown to have any effect on the progression or symptomatology of cataracts in dogs, and therefore have no role in its management. Provided that the dog’s retina is intact, this surgery will result in the return of vision. Cataract surgery on dogs is associated with a favorable risk profile and if you suspect your dog has cataracts, do talk to our vets at Hudson Veterinary Hospital to understand more.