Canine Cataracts: FAQ on Causes, Signs, and Treatment

Cataracts in dogs are a common eye condition, often linked to ageing but capable of affecting dogs of any breed or age. They cause a clouding of the eye’s lens that can lead to impaired vision or blindness if untreated. Understanding the basics about canine cataracts can help you spot warning signs early and seek the right veterinary care.

In this article, we address some of the most frequently asked questions on canine cataracts to help you look after your dog’s vision and health with confidence.

What exactly is a cataract in dogs?

A cataract is when the lens of a dog’s eye becomes clouded due to the clumping of proteins, which blocks light from reaching the retina. This produces a milky or cloudy appearance in the eye and hinders your dog’s ability to see clearly. Cataracts can develop in one or both eyes and may progress to partial or complete blindness if left untreated.

How do cataracts develop and progress?

Cataracts develop gradually in various stages:

• Incipient stage: Less than 15% of the lens is affected usually with no vision loss.
• Immature cataracts: Cover 15–99% of the lens; dogs experience some partial vision impairment.
• Mature cataracts: The entire lens is opaque, leading to near-total blindness.
• Hypermature cataracts: The lens shrinks and wrinkles; potentially causing inflammation.

Early-stage cataracts might be small and subtle, but as they grow, vision becomes increasingly compromised. Not all cataracts progress rapidly; some may remain stable for years.

What causes cataracts in dogs?

Cataracts can arise due to several factors including:

• Genetics: Certain breeds have a predisposition to inherit cataracts. Responsible breeders use screening tests before breeding to reduce risk.
• Diabetes mellitus: A leading cause that can cause cataracts to develop rapidly.
• Age-related changes: Natural lens aging leads to cataract formation in older dogs.
• Eye trauma or inflammation: Injury or chronic inflammation may trigger cataracts.
• Some medications: Rarely, certain drugs may contribute to cataract development.
• Nutrition and health: Poor general health or diet potentially increase risk.

How can you recognise if your dog might have cataracts?

If you notice a cloudy, milky film in your dog's eyes, this could be an early sign. Other symptoms include your dog bumping into objects, clumsiness, or reluctance to move confidently, suggesting impaired vision. Older dogs are particularly at risk and should have regular veterinary eye checks.

Do cataracts always lead to blindness, and is surgery necessary?

Cataracts usually cause vision loss if they mature fully, but not all cataracts progress to total blindness. Surgery is the only effective treatment to restore vision and generally involves removal of the clouded lens and replacement with an artificial one. However, surgery may not be suitable for all dogs, especially older ones or those with other health issues.

Your vet will evaluate your dog's overall health and the stage of cataract to discuss the best treatment option. Some dogs adapt well to partial or full blindness, so surgery is not always immediately necessary.

Are certain breeds more at risk of canine cataracts?

While cataracts can affect any breed, some breeds are more genetically prone. Responsible and ethical breeders undertake eye screening to minimise hereditary cataracts in their breeding lines. Maintaining regular veterinary check-ups, a balanced diet, and good general health can aid in early identification and management.