Cataracts in dogs and what are its symptoms?

Cataracts in dogs

Cataract refers to the loss of transparency (clouding) of the lens, which can make the dog partially or totally blind.

A pretty serious eye condition, cataracts don't just happen in older dogs, despite what you might think. Apparently, healthy puppies and young adults can contract this disease, resulting in partial or even total vision loss. What are the causes of cataracts? How does it manifest itself? How does it affect the daily life and behavior of the sick dog? Are there any treatments? This is what we will see together.

What is a cataract?

A cataract is the clouding of the lens. This structure is one of the main components of the eye, whose role is to conduct light rays on the retina. In the event of a cataract, the lens loses its transparency. To be more precise, it is the outer capsule and the inner matrix of the lens that becomes opaque. As a result, light can no longer reach the retina, resulting in reduced vision. In some cases, this can lead to complete loss of sight.

Dogs affected by this condition can find themselves completely disoriented, especially if it comes on suddenly and develops quickly. The causes of the disease are diverse, which may be related to the dog's advanced age or to another pathology.

A study at the Toulouse veterinary school showed a predisposition of certain breeds for cataracts: Poodle and Cocker, but also Yorkshire, Bichon, or even Labrit (Berger des Pyrénées).

Cataracts due to age

When this disease is associated with the advanced age of the dog, it is called a senile cataract. With aging, the lens gradually becomes cloudy, just like in humans.

This problem appears around 9/10 years, the age from which the dog is considered senior.

Typically, senile cataract affects both eyes.

Cataracts caused by disease

One of the diseases that can lead to cataracts is often diabetes. In diabetic dogs, it is the disorders characterizing the metabolism of carbohydrates that affect the dog's eye capacity. Like cataracts of age, cataracts associated with diabetes usually affect both eyes.

Other eye conditions can also promote the development of cataracts, including uveitis (inflammation of the uvea) and glaucoma, which is the increase in pressure inside the eye.

Congenital and hereditary cataracts

The puppy can be born with a predisposition to cataracts. However, it is very difficult to diagnose it before the age of 3 months. When congenital, cataracts can herald other eye conditions due to deformities.

Other forms of cataracts can appear later, around two years old. Both eyes can be affected, but not always at the same time or at the same rate.

Thus, cataracts can occur in various forms. Any cataract occurring in a relatively young dog of undetermined origin should be considered as possibly hereditary. Thus, in the absence of a diagnosis, the appearance of such a cataract should lead to the animal being excluded from reproduction.

Cataracts following trauma or poisoning

Blows, shocks, and other trauma can cause clouding of the lens of a dog.

Ditto for toxic substances such as naphthalene (commonly used in the fight against mites), as well as molecules such as chlorpromazine, used in the composition of certain drugs.

What are the symptoms of cataracts?

In cases of advanced cataracts, it is quite easy to notice it by the fact that the pupil of the dog has become partly or totally white. This is the most tangible sign of clouding of the lens, with the bluish reflection in the eye.

Before that, it is the observation of the dog's attitude that allows us to realize this. The animal that had lost its vision can start hitting all kinds of obstacles: objects, furniture, other people, etc.

Some dogs become nervous and even aggressive because they are surprised by other animals or humans who find themselves near them without them having the opportunity to see them approaching.

Can we cure cataracts?

Most often, the clouding of the lens is irreversible. Treatments now consist of slowing down this loss of transparency of the lens.

In older dogs, this involves the administration of drugs aimed at fending off the progressive vision deficit.

Cataracts can be corrected surgically: the damaged lens is removed and most often replaced by an implant. This operation is particularly indicated in young animals, such as a cataract due to diabetes or a congenital disorder. In other cases, the owner and the veterinarian should work together to assess the benefit/risk ratio of such an intervention. A rather expensive operation (1400 euros on average), is accompanied by restrictive treatments, including the regular application of eye drops in the eyes for several weeks. However, the success rate has increased significantly in recent years with the adoption of new techniques, now reaching 97%.