A cataract in dogs is an opacity in the lens of a dog’s eye, causing blurry vision. If small, the cataract won’t disturb the dog’s vision too much, but they must be monitored because the thicker and denser they become, the more likely it is they will lead to blindness for your dog.
Cataracts is developed in a number of ways: trauma to the eye, old age, disease or genetics are the most common. In fact, cataracts may even be present at birth in some Boston Terriers which is why it’s important to have a vet look at your puppy as soon as possible. In addition to the listed causes of cataracts, it may also develop from diabetes in your dog.
It’s important to monitor your dog’s eyes regularly. If you notice a bluish-gray cloud [see below] in your dogs eyes, we recommend getting to your veterinarian as quickly as possible. An untreated cataract may luxate (slip) from the tissue that holds it in place on the eye, causing it to move around in the eye where it can settle and block natural fluid drainage. Letting cataracts worsen can lead to glaucoma, which is known to cause permanent blindness. In addition to blindness, cataracts may also dissolve, causing deep, painful inflammation in the eye.
If vision loss does occur, surgery is the only option to restore sight to the affected eye. The affected lens will be removed and be replaced with a plastic or acrylic lens. Cataract surgery generally has a good success rate, but your veterinarian will need to determine whether your dog is a good surgical candidate. The procedure also requires extensive postoperative care.
[Information provided by PetMD]