The amazing, multi-talented companions we call our dogs are often praised and lauded for their astonishing sense of smell—a sense that is at least 40 times greater than our own—and their hearing, as they are able to pick up on certain high frequencies from distances as far as 500 feet—sounds that are essentially inaudible to our own ears.
However, the sense of sight in dogs is also very remarkable and super important to their overall health and well-being.
And when that sense starts to fade, either due to injury, a specific eye condition or old age, it can create major obstacles to our pets’ lives.
The importance of a dog’s sight to its general overall health cannot be ignored, but also important is the ability of we, as their owners, to pick up on the subtle and overt clues that may indicate this vital sense is beginning to fail or dwindle.
Although it is fairly rare for a younger dog to go completely blind, the steps we take now to both notice the fading sense and act to protect it from further damage can make a very positive difference in that dog’s life.
To correlate all this information, in this article we will talk more about blindness and fading vision in dogs—the various causes and how those causes develop over time.
We will also spell out some of the signs and signals you should watch out for in terms of blindness, and explain some proactive and reactive measures you can take when you notice any one of them starting to plague your dog.
The Causes of Blindness and Low Vision in Dogs
As we alluded to briefly above, dogs can begin to lose their vision—either gradually or suddenly—for any number of reasons; reasons ranging from injury to medical diseases to advancing age.
The exact cause for this very serious condition can only be determined and diagnosed by a veterinarian or some other pet health care specialist, so it is vital that you make an appointment as soon as possible if you begin to recognize any of the signs of fading vision (signs we will cover in more detail in the next section).
Some of the causes for blindness in dogs are much more common than others, including the eye diseases known as cataracts and glaucoma; and some breeds are certainly more susceptible to this condition than others.
Moreover, dogs that have a family history of blindness—and the various conditions that contribute to it—are much more likely to encounter these problems than others.
Here, according to experts in the field, are some of the main causes of blindness in dogs:
Glaucoma
According to experts on the website, PetMD, glaucoma in dogs is defined by “abnormally high pressure in the eye.”
So what does this mean exactly?
In the inner part of a normal eye, there is a consistent development and drainage of eye fluid—a teary fluid called aqueous humor.
When something negatively prohibits this eye fluid from draining, pressure can build up within the eye, causing pain and discomfort.
Moreover, high eye pressure within the inner eye can also compress, and lead to significant damage of, the optic nerve (the nerve responsible for sight).
The exact causes of glaucoma are placed into two categories: primary and secondary.
In primary glaucoma, there is typically a deficit of some kind in the area where aqueous humor leaves the eye.
This deficit can be due to structural damage of the eye itself, or to the particular drainage duct that allows the fluid process to function.
Primary glaucoma is generally an inherited condition, and the age of onset in dogs tends to vary somewhat by breed.
With secondary glaucoma, the disease occurs as a side effect to some other eye condition or injury, of which there are many.
These “other” eye conditions can indirectly affect the flow of eye fluid, resulting in the pressure and optic nerve damage so common with glaucoma.
While primary glaucoma has no known precipitating cause and is therefore characterized as an inherited condition; secondary glaucoma can be caused by any number of factors, including inflammation, infection, lens luxation (a dislocation of the eye lens), trauma and tumors of the eye and surrounding tissue.
Doctors look for a lot of different signs and symptoms when diagnosing glaucoma in dogs, some of which may also be visible to us, outside of an official vet’s diagnosis.
These signs may include:
- Redness of the eye
- Squinting
- Signs of pain (from the eye pressure)
- Tearing
- Pupils that do not react normally to light (dilated pupils)
- Cloudy corneas (the front surface of the eye)
- Bulging eyes (from the pressure), known as buphthalmias
- Blindness
Glaucoma is one of the most common reasons for blindness in dogs.
It tends to occur more in dogs of advanced age, especially primary glaucoma, but can result from injuries and other conditions (secondary) at any age.
Cataracts
Cataracts are very, very common in older dogs, and this condition can also lead to blindness if left untreated.
Just like with humans, cataracts is a gradual disease that over time impacts the lens of the eye, causing it to become cloudy and eventually impacting a dog’s vision.
Surgical treatment for cataracts in dogs involves removing the clouded lens and manually replacing it with a new one.
The procedure is safe, but often expensive, and the recovery time varies by age and breed.
Other Causes of Blindness in Dogs
While glaucoma and cataracts are the two main causes of blindness in dogs, there are additionally many other conditions that can lead to low vision and total blindness if left untreated.
Some of these conditions include:
- Diabetes. In dogs with diabetes, a condition characterized by high levels of glucose in the blood, cataracts can form and eventually lead to blindness.
- Progressive Retinal Atrophy. Also known by its initials, PRN, progressive retinal atrophy is a congenital condition that leads to gradual deterioration of the retina. It almost always leads to blindness over time.
- Sudden acquired retinal degeneration. Also known by the acronym, SARD, sudden acquired retinal degeneration is a scary disease with no known causes. In affected dogs, the disease comes on suddenly and can lead to total blindness in just a matter of weeks.
- Severe Entropion. This condition of the eye—a condition that can be either inherited or acquired—is characterized by inward-turning eye lids. As this process occurs, it can cause extreme pain and discomfort to your dog, and eventually blindness if not treated.
- Keratoconjunctivitis sicca. Also known simply as “dry eye,” this eye disease is characterized by deposits forming on the cornea portion of the eye, causing low vision and sometimes even total blindness.
Most of these conditions are treatable if caught early, so it is vital that you report any strange symptoms you may notice to your vet immediately.
How Can You Tell If Your Dog Is Going Blind?
Now that you understand the various diseases and conditions that can cause blindness and low vision in dogs, let’s talk about some of the signs and symptoms you can look for as a non-medical caretaker of that dog.
Below we have listed and explained just a few of these signs:
Running into Things
If you have had your dog for a while, he probably knows the ins and outs of your home like the back of his, well, paw.
So when he starts to bump into things he should otherwise notice and see, and perhaps yelp out of pain as he darts away, it could be because his vision is starting to fade.
To help your dog out in this arena, start by moving away any heavy or potentially accident-producing obstacles from his normal path, and practice walking your dog via this path so he grows more accustomed to it.
Remaining in One Specific Part of the Home
If one specific part of the home feels safe and secure to your dog—a dog that may be losing his vision—he may just remain there and refuse to go to other parts of the house.
He may also have a hard time finding things like his food and his water.
This refusal to leave a “safe space” is simply your dog’s way of self-preservation—and a clear sign that he may be losing his sight.
Allowing your dog to take his meals and drink his water in this safe space can be a great way to ensure your dog is properly cared for while also preventing unwanted accidents.
Less Active and Playful
Dogs losing their vision will be less apt to play and certainly less active.
They may even become irritable or annoyed at those who try to get them to play, or at those that try to move them from their safe space.
Eye Abnormalities
Finally, dogs going blind may have some abnormalities that are very plain to see.
Dogs with glaucoma, for instance, may present with red or bulging eyes from the irritation and pressure, respectively; and dogs with cataracts will have eyes that look clouded over.
You should also look for squinting in your dog’s eyes and any signs and symptoms that might indicate he is pain.
Last Word
Low, fading vision and blindness can happen to any dog, but it is definitely more common in those of advanced age.
This is typically when diseases like glaucoma, cataracts and others begin to occur and gradually get worse.
The early signs of blindness or low vision—running into things, becoming less active, etc.—should be reported to your vet as soon as possible.
Depending on the age of your pet, there are many treatments available that can either prolong what little sight your dog has left or, in some cases, restore his sight completely.