A cataract is an opacity in the lens. This opacity scatters light as it passes through the eye. That’s an obvious problem, because the lens is the part of your eye (and your pet’s eye) that focuses light on the retina to see. The less light, the worse the vision.
What causes cataracts?
The biggest driver of cataracts in dogs is inherited genes. Many pure-bred dogs and even mixed-breed dogs carry genes that make them liable to develop cataracts. Another common cause is diabetes, which can cause cataracts to appear and worsen very quickly.
Life and how we live it can cause cataracts, too, as dogs develop them as they age and as a result of a lot of exposure to UV light from a lot of bright sunlight and life in higher altitudes (people in mountainous Nepal are prone to cataracts).
Can cats get cataracts?
In my ophthalmology practice, we don’t do nearly as many cataract surgeries on cats. (I’ve actually done more cataract surgeries on birds than cats!) Why? Fewer cats are born with the genetic predisposition to get them than dogs. But cats do get a lot of chronic intraocular inflammation and that can lead to cataracts. If you notice vision problems or cloudiness in your cat’s eye, it’s crucial that you visit your veterinarian for a thorough eye exam and to check for underlying conditions like viral infections that can cause eye problems.
What are the signs of cataracts?
Cataracts that are bad enough to affect vision, causing dogs to bump into or fall off things, look like cloudiness on the eye. But other conditions can appear as cloudiness, too. Nuclear sclerosis develops as your dog ages and it’s a normal age change. The difference is, nuclear sclerosis still allows a clear image to form on the retina, and cataracts don’t. Do you know when a car’s headlight or a flashlight in the dark catches your dog’s eye and it reflects the light? Nuclear sclerosis lets that happen. Cataracts don’t.
It might be you or your veterinarian who notices your dog’s vision problems first. Your veterinarian might see cataracts during a physical exam. If your dog looks like a possible candidate for cataract surgery, your veterinarian may refer you to an ophthalmologist like me who operates on eyes to fix them. These surgeries are more successful today than ever before, so whether your dog is slowly developing cataracts in old age, or quickly because of inflammation or diabetes, it’s crucial to get those eyes checked.
A long time ago, cataract surgery was harder on our pets than it is today. An eye surgeon (like me!) needed to make a particularly big incision in the eye to remove the lens and replace it with an artificial one. Dogs experienced a lot of inflammation, and outcomes weren’t nearly as good as they are today. Veterinarians would often hesitate to operate until cataracts were extremely advanced.
Today, the success rate for a successful outcome, with improved vision and quality of life, is 90 to 95% for typical candidates for surgery. With the new procedure, a board-certified ophthalmologist like myself makes a much smaller incision in the eye, causing less irritation to the eye and less inflammation. I also use a machine called a phacoemulsifier that makes ultrasonic sound waves to break up the lens, then I suction out smaller pieces without needing to remove the entire lens intact. When the old lens is removed, I replace a new, artificial lens into the eye.
What if cataract surgery isn’t an option?
Dogs who are not good candidates for cataract surgery can still receive medical help. While there’s no way to remove cataracts without surgery, anti-inflammatory eye drops, once or twice a day, as prescribed by your veterinarian, may help decrease the long-term risk of glaucoma, or high pressure, that can cause your pet pain. Watch for increased redness and squinting, and bring your dog in at least twice a year so the veterinarian can check for other medical problems.
If your dog’s vision is bad, there are also a few things you can do back home for safety. Even dogs with poor or no eyesight can remember their surroundings over time, so don’t rearrange furniture. Protect them from falls by keeping balconies and flights of stairs off limits, and watch them carefully if you visit somewhere other than your familiar home, as a dog struggling with vision may be fearful and prone to injury.
What’s life like after cataract surgery?
The differences for a pet who responds well to cataract surgery can be really dramatic. Many dogs I operate on are blind or close to blind. They often can’t see anything, are bumping into things, and are frightened in life. I’ve seen the surprised look on their face when they wake up from surgery and start looking around wondering what just happened. Within a few weeks, they’ve got good vision, as good as it was before cataracts.
A dog I saw a few weeks ago was almost too scared to walk. Now, he’s back to playing and acting like a younger dog. Some dogs who are carried around everywhere may be less bothered by their worsening vision, but a dog who lives to chase a ball and run around is helped a lot by cataract surgery.
Most of us are aware of cataracts, but maybe this Cataract Awareness Month you’ll be a little more aware of how far we’ve come in cataract surgery to improve the quality of life for pets.
Dr. Nancy Johnstone McLean is a board-certified ophthalmologist at VCA Veterinary Care Animal Hospital and Referral Center, and her areas of interest include cataract surgery, glaucoma and systemic diseases that affect the eye. Why eyes? Years ago, in veterinary school, Dr. McLean says eyes aren’t just a window the soul, but figured out that eyes were a window for her to climb through to mix medicine and surgery every day in practice and offer the opportunity to work on horses and your much smaller cats, dogs (and birds).
“Today, the success rate for cataract surgery with improved vision and quality of life is 90 to 95% for typical candidates for surgery.”