Cataracts in dogs

isolated dog

Overview

  • A cataract is an abnormal cloudiness of the eye, caused by a change in the lens. Cataracts stop light reaching the back of the eye, reduce vision and eventually cause blindness.
  • Many different conditions can cause cataracts to develop.
  • Cataracts aren’t reversible, but fortunately, dogs often cope with them very well.
  • Cataract removal is available at specialist eye clinics.
  • Book an appointment with your vet if you notice your dog’s eyes becoming cloudy; there are a few possible causes.

Do cloudy eyes mean my dog has cataracts?

Cloudy eyes don’t always mean cataracts, there are a few possible causes.

Cataracts explained

A cataract is an abnormal cloudiness of the eye, caused by a change in the structure of the lens. Normally, light passes through the lens and projects an image onto the back of the eye (retina). Cataracts stop light getting through and reduce vision.

Cataracts usually get worse over time, causing loss of vision and eventually, complete blindness.

Illustration showing cataracts in a dog's eye

Cataracts stop light getting through the lens. Click image to enlarge.

Causes

Many different conditions can cause cataracts to develop:

Old age

Cataracts can develop due to old age; we call these ‘senile cataracts’. Senile cataracts often develop slowly and cause a gradual loss of vision.

It’s important to remember that cloudy eyes aren’t always caused by cataracts. ‘Nuclear Sclerosis’ (a very common condition in older dogs), also causes cloudy eyes. Nuclear sclerosis is a natural ageing process and doesn’t affect vision unless it becomes very severe.

Diabetes

It’s very common for diabetic dogs to develop cataracts. High blood sugars lead to sugar entering the lens, turning it cloudy. Diabetic cataracts often develop quite quickly and cause a complete loss of vision.

Other eye disease

Eye disease, eye injuries and toxins can all lead to cataract development. Common examples include:

  • Glaucoma (high pressure inside the eye)
  • Lens luxation (movement of a lens out of position)
  • Uveitis (inflammation inside the eye)
  • Injury (to the inside of the eye).

Hereditary cataracts

Certain breeds of dogs inherit a high risk of developing cataracts (often along with other types of eye disease). Some are born with them (congenital cataracts), and others develop them in time. High-risk breeds include Golden Retrievers, Miniature Schnauzers, West Highland White Terriers and Old English Sheepdogs (this is not a complete list - always research your breed).

Symptoms

The signs of cataracts developing are not always as obvious as you might expect, especially if they develop slowly, over a long period. You may notice:

  • A cloudiness, or grey tinge in your dog’s eye(s) - you may only notice this when light strikes the eye at a certain angle, or perhaps when you take a photograph of your dog.
  • Loss of vision, especially in low light conditions - this can be very tricky to notice because it often develops slowly and most dogs are very good at adapting by using their hearing and sense of smell instead.
  • Pain - cataracts aren’t painful, but some of the underlying conditions that cause them are (such as eye injury or glaucoma).
Photo of a dog with cataracts

Cataracts can make the eye appear cloudy.

When to contact your vet

Contact your vet if you notice any changes in your dog’s eyes, or if you think they are losing their vision.

You know your dog best. If they don’t have the symptoms listed above but you are still concerned it’s always best to contact your vet.

Treatment and cataract surgery

Treating the underlying cause

If your dog’s cataracts have developed due to a specific condition, they will need that condition treated to limit further damage to their eyes. It is important to understand that treating the underlying condition may slow the development of your dog’s cataracts, but won’t get rid of them. The only way to get rid of cataracts is to remove them.

Leaving cataracts without treatment

Many dogs cope so well with cataracts that surgery (to remove them) isn’t required. This is especially true for dogs that lose their vision slowly (e.g. dogs with senile cataracts). For more information, read our article ‘Caring for a blind dog’. You will need to adapt your house and lifestyle to suit a blind dog so they have the best chance of coping and staying safe.

Cataract surgery

If your dog isn’t coping well with cataracts, you may opt for surgery (to remove them). Cataract surgery is only performed by specialist vets at referral centres. After surgery, your dog will need careful nursing and regular check-ups to help them recover and make sure everything is going as expected.

Prevention

It’s important to do your research before getting a dog. If you are considering getting a breed that is at risk of eye disease, you should check whether their parents have been screened under the ‘Eye Scheme’. The Eye Scheme is run by the British Veterinary Association, Kennel Club and International Sheep Dog Society and currently screens 59 dog breeds for 11 types of inherited eye disease (including the common forms of cataract).

Cost

Treatment for a dog with cataracts can become very expensive, especially if surgery is necessary. It’s very important to speak openly to your vet about your finances, the cost of treatment, as well as what you think is right for your dog. There are often several treatment options so if one doesn’t work for you and your pet then the vet may be able to offer another.

Consider insuring your dog as soon as you get them, before any signs of illness start. This will ensure you have all the support you need to care for them.

Published: November 2019

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Written by vets and vet nurses. This advice is for UK pets only.

Illustrations by Samantha Elmhurst