Canine Cherry Eye: While not necessarily painful as much as irritating, canine cherry eye, occurring more frequently in some breeds, is corrected with surgery to reposition the displaced tear gland behind the third eyelid.
Pigmentary Keratitis (PK): A condition caused by the invasion of blood vessels into the normally clear cornea, PK is usually genetically linked with certain breeds. German Shepherds are probably the breed in which this disease is encountered most frequently. Invading vessels transport pigment into the cornea and deposit it there, and if allowed to advance unchecked, PK will in time cause a physical blockage to vision. The invasion of blood vessels can usually be controlled by the application of medication into the eye, or by injecting steroids into the critical point between the cornea and sclera (white) of the eye.
Cataracts: Cataracts occur frequently in certain dog breeds, or as a result of conditions such as diabetes, or simply due to age. In most healthy animals, the clouded lens can successfully be removed during surgery.
Distichiasis: Some breeds are more prone than others to the condition known as distichiasis, which occurs when the eyelashes are abnormally located on the eyelid causing irritation and infection to the eye.
Glaucoma: Glaucoma is caused by increased pressure within the eye due to a build-up of fluids that do not drain properly. Dog glaucoma is the leading cause of canine blindness, which can occur within as little as 24 hours, or slowly and painfully over a period of weeks or month.
Progressive Retinal Atrophy (PRA): This genetic condition affects dog eye health in that it damages the retina and causes a loss of vision particularly at night, with limited vision during the daytime. There is no cure or treatment for PRA, although most dogs will adjust well as the condition is either seen first at birth or progresses slowly after the dog is several years old.
Ectropion: This is another surgically correctable eyelid problem. If too much loose facial skin causes the eyelids to sag excessively, the exposed conjunctiva is subject to infection. Predisposition for this condition is sometimes inherited but may occur in mixed breeds.