Cataracts In Dogs
By Chyrle Bonk, DVM October 05, 2021
You may notice all sorts of changes as your dog ages. They may get grey hairs on their muzzle, their hearing might not be as good, and they may develop issues with their vision. One of those common issues is cataracts. Cataracts are often a normal part of the aging process for a dog’s eyes. So, what can be done?
What Are Cataracts?
A dog’s eye is very similar to the human eye. The outer, clear surface is called the cornea and the colored part is called the iris. Under the iris lies the lens, whose main job is to focus light onto the back of the eye, or the retina. The retina is the part of the eye that is responsible for turning light into images that are perceived by the brain. Between the lens and the retina is the vitreous chamber which contains proteins floating around in water.
Cataracts refer to a cloudiness that can develop on the lens. Since the lens is responsible for focusing light, it needs to remain crystal clear in order to work properly. Any cloudiness of the lens can decrease its function.
What Causes Cataracts?
Cataracts in dogs may happen for a number of reasons, some of which are preventable.
- Old age
The cloudiness of a cataract is caused by proteins in the eye clumping together on and in the lens. This is something that can happen as dogs age.
- UV damage
UV light from the sun can cause damage that increases the clumping ability of the eye proteins. This usually takes some time to occur, so it tends to happen to dogs later in life.
High blood sugar levels can lead to abnormal cellular metabolism in the lens, causing cataracts to pop up quickly if diabetes isn’t managed properly.
Occasionally, injuries to the eye can lead to inflammation that leads to cataracts.
Some breeds are more predisposed to cataracts than others. Cataracts due to a genetic cause tend to show up earlier in life than those by other causes.
What Dogs Are Prone To Cataracts?
Since there is a genetic component to cataracts in some breeds, purebreds and mixes of those breeds will be more prone to developing cataracts. Those breeds include: Cocker Spaniels, Poodles, Yorkshire Terriers, Boston Terriers, Australian Shepherds, and Labrador Retrievers, to name a few.
Also, dogs with diabetes are more prone to cataracts, especially if their diabetes isn’t managed properly.
What Are The Signs Of Cataracts In Dogs?
Most of the time, you’ll be able to actually see cataracts in your dog’s eyes. They will look like cloudiness in what used to be a clear eye. Other signs include you noticing your dog having trouble catching treats or the ball, or they seem to stumble when climbing up or down stairs. They may also bump into things or spend more time smelling objects rather than looking at them.
If cataracts remain small, they will have little impact on your dog’s vision, but you may notice small deficits especially depending on where the cataracts are located on the lens. Generally, cataracts grow slowly and gives your dog time to compensate for changes in their vision. However, there are instances when dogs with diabetes develop cataracts very quickly and may show signs of visual impairment.
Can Dogs See With Cataracts?
With most types of cataracts, dogs are able to see fairly normally until the cataract covers 30% of the lens. When the lens coverage is more than 50%, most dogs will start to show some symptoms of vision loss. Dogs will go blind in the eye when 100% of the lens is covered by a cataract.
Cataracts of old age and UV damage tend to come on fairly gradually. This gives your dog a chance to adjust to any loss of vision. For dogs with diabetic cataracts that come on more quickly, they may have more trouble adjusting and start to show signs of vision loss much earlier.
How Are Cataracts Diagnosed In Dogs?
If you notice any cloudiness in your dog’s eyes or feel like they just aren’t seeing things as clearly as they once did, take them to see your veterinarian. Often, veterinarians can even diagnose cataracts during regular exams before you notice any changes in your pup.
The veterinarian will shine a light into your dog’s eyes to try to visualize the retina. Cataracts will block some of that light, not allowing full visualization of the back of the eye. Your vet may then perform blood work or other diagnostics to look for underlying causes of cataracts.
Are There Treatments For Cataracts In Dogs?
Treatment will depend on which category of cataract your dog has, as well as the cause of it and the progression. Cataracts fall into four main categories.
- Incipient cataracts
Incipient cataracts are small, covering 15% or less of the lens. They usually don’t cause any problems with vision.
- Immature cataracts
This stage of cataract covers about 30% of the lens, which can be in different areas. There is usually very little visual impairment.
- Mature cataracts
These cataracts cover the entire lens and cause near blindness or complete blindness.
- Hypermature cataracts
This occurs when the lens starts to shrink and appear wrinkled.
Incipient cataracts usually don’t require treatment because they are not affecting vision. However, monitoring the eyes for further cataracts growth is recommended. Immature cataracts are typically not treated as well since they are not causing blindness.
Mature forms of cataracts can be removed with surgery by a veterinary ophthalmologist. The procedure requires general anesthesia and removal of the affected lens. A new plastic lens is inserted. Most dogs recover quickly from surgery but do require anti-inflammatory eye drops for weeks to months following the procedure.
Can Cataracts In Dogs Be Prevented?
Since there is a genetic component to cataract formation, it’s hard to prevent them completely in those breeds that are more prone to them. However, there are screening tests available for breeding animals to help decrease the likelihood of passing cataracts to offspring.
In dogs with diabetes, proper management with insulin, diet, and exercise can help decrease the formation of cataracts. Strict attention and regular monitoring need to happen to keep blood sugar levels in check so that it can’t damage a dog’s eyes.
Exposure to the sun should be limited, especially in breeds that are prone. Always provide your pup with shade or even doggie sunglasses or hats to keep those harmful rays out of their eyes when outside.
What To Do If Your Dog Has Cataracts?
A diagnosis of cataracts is not the end of the world for you or your pup. It just means you’ll have to take some extra precautions to help them navigate their world the best they can. The first question you’ll need to ask yourself is if surgery is an option. This will depend on the cause of your dog’s cataracts and their progression. Eye surgery is often expensive, so you will need to decide whether this is something within your budget. You will also want to consider your dog’s age and other health issues before you put them through surgery. Surgical removal carries a great prognosis, but it isn’t for every dog, so be sure to discuss this option with your veterinarian if you’re interested.
If you choose not to have your dog undergo cataract surgery, it’s not over. There are things you can do to help increase their comfort with vision loss. First of all, get any underlying conditions under control, if applicable. Make sure diabetes is properly managed and your dog is kept out of the sun as much as possible.
Next, don’t make any sudden changes in your pup’s environment. Once they get used to a certain furniture arrangement or route around the neighborhood, they’ll be able to navigate fairly effectively even with major visual impairment. However, rearranging the furniture or taking them on a different hiking path can create safety issues and make them nervous or uncomfortable. You can definitely be their seeing eye person, but don’t underestimate a near blind or blind dog’s ability to get themselves around.
For dogs that develop cataracts more quickly, you may need to spend more time showing them around than other dogs. But they will still be able to become accustomed to decreased vision and do fine for the long run.
Cataracts are often accompanied by some inflammation which can be painful. Cataracts may also lead to glaucoma later on, which is very painful. Because of this, many veterinarians will prescribe anti-inflammatory eye drops to help relieve your dog’s discomfort as their cataracts progress. These drops are typically a lifelong treatment, but regular use can make a difference in your dog’s comfort.
Cataracts are a common sign of aging in most dogs. They can be brought on by a number of reasons, including diabetes, injuries, and most commonly genetics. Most dogs will live just fine with some amount of cataracts, while others may eventually go blind from them. Surgical removal is the only cure, but this isn’t a feasible option for every dog. Knowing how to make your dog comfortable with cataracts will help them age more gracefully and live as comfortably as possible.