What are cataracts?
By Dr. Weinstein
A cataract is any opacity within the lens. There are different levels of cataracts. The first is called an incipient cataract: the opacity is so small that it is not yet affecting vision. An immature cataract takes up more space in the lens and can cause blurred vision. A mature cataract gives the eye a cloudy appearance and causes vision loss. The final stage for a cataract is called a hypermature cataract. At this point, due to a loss of water and proteins in the lens, the lens actually begins to shrink.
Why do dogs develop cataracts?
Some cataracts are inherited; certain breeds are more prone to cataracts such as Afghans, Cocker Spaniels, Chesapeake Bay Retrievers, German Shepherds, Golden retrievers, Labrador Retrievers, Schnauzers, Old English Sheepdogs, Huskies, Poodles, West Highland Terriers and Springer Spaniels. Cataracts can develop at any age, but are usually at ages 8yr and older. Some cataracts develop slowly, while others have a rapid onset.
Besides breed and age, diabetes is a leading cause in dogs developing cataracts. 75% of dogs with cataracts develop them within the first year of being diagnosed with diabetes. Another reason dogs develop cataracts is due to ocular disease. Ocular disease can be anything from retinal degeneration (thinning of the retina), uveitis (intraocular inflammation), or glaucoma.
Treatment for cataracts
Surgery is often used to treat cataracts, although not all cataracts need surgery right away; that is to be determined by the ophthalmologist. If surgery is determined necessary, there are three preoperative tests that will need to be performed to determine if the eye is optimal for surgery. Those include ERG (measures how well the retina is functioning), gonioscopy (an exam of the fluid drainage angle in the front part of the eye), and an eye ultrasound. Depending on the results of the tests, a retinopexy (eye laser procedure) may be recommended. For those that go to surgery, usually 2-3 days of hospitalization will be required. Usually vision is improved within the first week, and fully improved within 2-3 weeks.
After cataract surgery
Initially following surgery, there will be frequent eye medications that will be necessary to help with healing. Those medications will be weaned down over time as deemed by the ophthalmologist. Frequent rechecks will also be needed, but those will also be weaned down over time. Complications can be rare but can include: retinal detachment, glaucoma, bleeding in the eye, and ulcers.
What if surgery is not performed?
Cataracts can cause inflammation in the eye which can become serious and can lead to retinal detachment and glaucoma. Cataracts should be treated even if surgery is not performed. If surgery is not chosen, lifetime eye medications will need to be used to keep down the inflammation in the eye. Regular rechecks should also be scheduled to keep up on the health of the eye. Cataracts will eventually lead to blindness, but most dogs tolerate blindness well.