Cataracts are opacities within the lens of the eye that cause vision impairment and may lead to blindness. To an untrained eye, normal aging changes in the lens of the eye may appear as cataracts. Your veterinarian has special equipment to distinguish cataracts from aging changes. Cataracts develop more commonly in some breeds of dogs (e.g.: Boston Terrier, Cocker Spaniel) and in dogs with diabetes mellitus. Other causes of cataracts include ocular trauma, congenital (born with the condition), and inflammation within the eye (uveitis, glaucoma, drug reaction, radiation therapy). The ideal therapy for mature cataracts is surgical removal by a veterinary ophthalmologist. Removal of the cataract filled lens restores eyesight and minimizes complications associated with the cataract, such as glaucoma and uveitis. Successful outcomes require treatment and control of any underlying conditions (e.g.: controlling blood sugar levels in a diabetic patient).