My dog has cataracts

However, the latter is a symptom of a serious eye condition: glaucoma. That’s why it’s important to understand the difference between the two, and to know what to do in each case. To explain this properly, it helps to know how a dog’s eye is structured.

What does a dog’s eye look like?

To understand where cataracts occur, it’s useful to know a bit about the anatomy of the eye. From the outside in, the eye consists of: the cornea – anterior chamber – iris with an opening (pupil) – posterior chamber – lens – vitreous body – retina. The optic nerve extends from the retina.

Cataracts in dogs

When we refer to true cataracts, we mean a clouding of the lens. The lens focuses incoming images onto the retina and must remain clear to do so. Like in humans, the lens in animals becomes more opaque with age. This natural change does not lead to blindness.

If abnormal clouding occurs, we speak of a cataract. This can be congenital (present from a young age) or develop later in life. Diabetes is also a major cause of cataracts in older dogs. Other conditions such as retinal degeneration or progressive retinal atrophy (PRA) can also cause cataracts. In order to assess whether surgery is an option, these conditions must first be ruled out by a veterinary ophthalmologist.

Glaucoma in dogs

Glaucoma is a completely different condition involving increased pressure inside the eyeball. This is painful and may result in permanent blindness. That’s why it must be treated promptly.

There is always a natural pressure in the eye — otherwise the eyeball would collapse. This pressure is maintained by the continuous production and drainage of aqueous humour. If drainage is blocked, pressure builds up, resulting in glaucoma. Certain breeds, like the Siberian Husky, Flatcoated Retriever, and Bouvier, are predisposed to this condition (primary glaucoma). Glaucoma may also occur secondarily due to other eye problems, such as inflammation, lens luxation, bleeding, trauma or tumours.

Glaucoma often presents as a sudden bluish-white haze over the eye — not within the lens. Blood vessels in the white of the eye may appear engorged, the pupil may be dilated, and the eye will often be painful. This discomfort may be noticeable in your dog’s behaviour. If you suddenly notice a haze on your dog’s eye, contact your vet immediately.

Can cataracts be treated?

Here we’re focusing on the treatment of true (grey) cataracts. This form is not painful for dogs. It usually develops gradually, allowing dogs to adjust to reduced vision over time. Dogs rely heavily on their sense of smell and hearing and often manage well even with limited sight. Many owners don’t even realise their dog is seeing less. When cataracts are congenital, dogs don’t know any different and often behave normally. However, if cataracts develop suddenly, it may take longer for your dog to adapt, and they may appear uncertain. This could be a reason to consider surgery, particularly for working or assistance dogs.

The only treatment available is surgical removal of the clouded lens material. Whether this is necessary depends on the situation. If your dog is not affected by the reduced vision or blindness, surgery may not be required.

The overall condition of the eye also plays a role in the decision. Surgery is only worthwhile if the rest of the eye is healthy. The retina must still be functional — otherwise, your dog will remain blind after surgery. In such cases, surgery brings unnecessary risk without benefit.

If surgery is chosen, make sure you’re well informed about post-operative care, and allow your dog to get used to wearing a protective collar in advance.

Can cataracts be prevented?

If cataracts are congenital, they usually cannot be prevented. If your dog develops a condition that may cause cataracts — such as diabetes — prevention is only possible through early and appropriate treatment. Once formed, cataracts will not resolve on their own.

For age-related lens changes, there are products that may help support eye health. Examples include VT Phak Syrup and Sitalan, which is available as an oral suspension.

If you have questions about cataracts in dogs or about general eye care, feel free to contact us at [email protected].