Pet Keratoconjunctivitis Sicca (KCS)
Keratoconjunctivitis Sicca (KCS) is the decrease in the aqueous component of tears.
What are the signs of KCS?
The lack of tear production is very painful. Signs of ocular pain include squinting, rubbing, and avoidance of light (photophobia). Other symptoms associated with KCS include redness, cloudiness, and greenish, viscous ocular discharge.
What causes KCS?
The most common cause of KCS in the dog is immune-mediated. Most breeds, even mixed breeds, have been found to have a form of immune-mediated KCS. The breeds with the highest incidence of cataracts include Boston Terriers, Miniature Poodles, American Cocker Spaniels, Pugs, English Bulldogs, Miniature Schnauzers, Samoyeds, Lhasa Apsos, Pekingese, and Shih Tzus. Other causes of KCS include drug toxicity (sulfa drugs, Etogesic, and atropine), infectious (canine distemper and leishmania), loss of innervations to the cornea or tear glands, hormonal disorders (diabetes, cushings, hypothyroidism), or surgical excision of the gland of the third eyelid (cherry eye).
What is the treatment for KCS?
Medical treatment is often quite effective in the treatment of KCS. Topical immune modulators, name cyclosporine, have been shown to significantly increase tear production in 80% of dogs with KCS. However, in some instances, medical therapy is not sufficient to resolve the KCS. In those cases, surgical treatment is indicated. The surgery, termed a Parotid Duct Transposition, redirects a salivary duct to empty onto the eye.