Not that long ago, my cousin called me to tell me that his young American Bulldog had been diagnosed with cataracts. It is always especially upsetting when a young animal gets ill, because it is unexpected. Who expects their puppy to get cataracts? This week, we explore the causes, presentation and possible treatments for juvenile cataracts.
Before we go further, I would like to thank Tim J. Cutler, MVB, MS, Diplomate ACVO, ACVIM for his help in writing this blog.
The lens is a structure in the eye that sits behind the colored part (the iris). When you look at your dog’s eyes, there is a black circle in the middle of the iris called the pupil. Through and behind that space is the lens. The lens is supposed to be clear so that light can pass through it.
Cataracts are opacities of the lens or the capsule around the lens. In order to maintain the clarity of the lens, there is a fine balance biochemically. When that balance gets out of whack due to inflammation, trauma, or a host of other causes, the lens fibers can get damaged, causing the lens to get white (opacity). Cataracts can impair vision, lead to other ocular disorders, and they can also be painful.
Cataracts can be hereditary. Sometimes they are present in puppies at birth. These are called congenital and are fairly rare. They can also occur in dogs between 6 months and 6 years of age. These are called juvenile cataracts. If your puppy develops cataracts after she is born, it doesn’t mean that there was a hereditary influence, but certain breeds are predisposed. Hereditary cataracts are among the most common reasons for cataract development. There are genetic tests available for the following breeds for juvenile cataracts: Boston Terrier, French Bulldog, and the Staffordshire Bull Terrier.
Some other causes of cataracts in young dogs include metabolic (diabetes), inflammatory, secondary to progressive retinal atrophy, lens instability, as the result of other congenital abnormalities, or from toxic or traumatic injury (e.g., deep cat scratch).
In younger dogs, the rate of cataract formation is frequently intense (24-72 hours). Because there are so many causes of cataracts and damage can occur so quickly, changes in the eye should be addressed immediately. When in doubt, bring your puppy to the veterinarian if you see any signs that the eyes have changed in color or clarity. Also, if your puppy is squinting or scratching at her eyes, bring her in.
If your puppy has a complete cataract, she won’t be able to see well and she may start bumping into things. You may also see that the middle of the pupil has a white spot or area. Try shining a flashlight at your dog’s eyes or taking a picture with a flash. You should see that there is a colored reflection as you have seen when you encounter an animal as you are driving your car at night. If you don’t see a reflection, but instead see something grey or dull white, your puppy may have a cataract.
Treatment will depend on the cause of the cataract. Basically, your veterinarian will work to control any inflammation and diagnose the primary cause. Once the primary cause is diagnosed, your veterinarian may refer you to a board certified veterinary ophthalmologist. You can find one at http://www.acvo.org. Whether it is a specialist or your primary care veterinarian who treats your dog, they will focus on controlling the inflammation fast. Sometimes this type of treatment can continue for months or longer. If the cataracts are large, are affecting your puppy’s vision, or are causing pain, the veterinary ophthalmologist may recommend surgery.
Sometimes, if the puppy’s cataracts are small, they can be watched and may not need treatment. They won’t go away, but they may not enlarge very quickly. If this is the option that you choose (under advice from your veterinarian) you must stay vigilant and monitor your puppy’s eyes for any changes. Any change should cause you to make contact with your veterinarian.
When your puppy goes to get her eyes examined, it will be different than any other type of physical examination. She must stay very still for extended periods of time while a person about five inches from her eyes shines a light at her and forcefully holds her eye open. Prepare your dog for this by teaching her to hold her head still while a partner pretends to examine her eye. You can do this by holding a treat just far enough away from her nose that she will focus on it, but not try to take it from you.
You can also teach her to accept the kind of close contact restraint that is necessary for a thorough eye exam by putting your hands around her neck, ears, and muzzle each day for 1-2 minutes while giving her treats every 2-5 seconds.
The final element of the exam is the extended eye contact. Don’t forget that eye contact is intimidating to dogs. If you took your puppy to puppy class, she knows how to make eye contact with you. This can be a very helpful tool during an eye exam because she will already think that eye contact is rewarding and fun.
Prepare her now so that if she has to go to the ophthalmologist, the visit will be stress free!
Dr. Lisa Radosta