Dry Eye. A condition in which not enough tears are produced to keep the eyes properly lubricated. Dogs may inherit this condition; among the breeds at higher risk are the American Cocker Spaniel, English Bulldog, Pug, Lhasa Apso, Pekinese, Shih Tzu and West Highland White Terrier. Small, flat-faced dogs sometimes have eyes that bulge so much that their eyelids cannot close, which allows the surface of the eyes to dry out.
Dry eye may also result from an immune system reaction, an injury or a drug side effect. Dryness can be a serious problem because dry eyes are easily irritated and may develop conjunctivitis or corneal ulcers. Artificial tears, good eye hygiene, anti-inflammatory drugs and/or cyclosporine ointment (Optimmune) may help. If the cause is known, the veterinarian treats that as well.
Corneal Ulcer. A slow-healing sore on or in the cornea, accompanied by inflammation. Most ulcers are caused by injuries, and treatment often involves antibiotics. According to Samuel J. Vainisi, DVM, Diplomate, ACVO, of the Animal Eye Clinic in Denmark, Wisc., small dog breeds with very short noses and big eyeballs are more prone to eye injuries. “Because of that, we see a lot of ulcers on the eyes” of breeds such as the Boston Terrier, the Pekinese, and the Shih Tzu.
Cataract. A clouding of the lens that obscures vision. Cataracts are the most common cause of blindness in dogs. Most dogs with cataracts inherited the tendency to develop them. Inherited cataracts can occur in the Afghan Hound, American Cocker Spaniel, Boston Terrier, Chesapeake Bay Retriever, German Shepherd, Golden Retriever, Labrador Retriever, Miniature Schnauzer, Norwegian Buhund, Old English Sheepdog, Schnauzer, Siberian Husky, Staffordshire Bull Terrier, Standard Poodle, Welsh Springer Spaniel and West Highland White Terrier. Diabetes, injuries, poor diet and aging can also lead to cataracts.
Removing the lens allows light to again enter the eye. For best post-surgery vision, the natural lens is usually replaced by a plastic lens. “The surgery itself is not too stressful for the majority of patients,” says Dr. Lim. However, “the first few weeks postoperatively can be stressful because it is very intensive—the patient must wear an Elizabethan collar at all times, and several medications are required.”
Glaucoma. Elevated pressure of the intraocular fluid (fluid inside the eyeball) caused by fluid draining more slowly than it is produced. Glaucoma can damage the retina or optic nerve.
Most often, a dog gets glaucoma because she inherited an eye structure that leads to poor drainage. Breeds in which primary (inherited) glaucoma occurs include the Alaskan Malamute, American Cocker Spaniel, Basset Hound, Beagle, Boston Terrier, Bouvier des Flandres, Chow Chow, Dalmatian, English Cocker Spaniel, English Springer Spaniel, Great Dane, Labrador Retriever, Norwegian Elkhound, Poodle (all sizes), Samoyed, Shar-Pei, Shih Tzu, Siberian Husky and Welsh Springer Spaniel.
Primary glaucoma has no obvious cause and affects both eyes, although one eye may develop glaucoma earlier than the other. Secondary glaucoma is glaucoma that is caused by a dislocated lens, injury, tumor or other problem that decreases fluid drainage in the eye; it may affect just one eye.