INDUSTRY INSIGHT
VETERINARY SERVICES
SPONSORED CONTENT
DRY EYE IN DOGS
Kara Gornik, DVM, DACVO
Ophthalmologist at Pittsburgh Veterinary
Specialty and Emergency Center (PVSEC)
K
eratoconjunctivitis sicca (KCS), commonly known as dry
eye, is a relatively common condition in dogs. Dry eye can
occur in any breed, but the Cavalier King Charles Spaniel,
English Bulldog, Lhasa Apso, Shih Tzu, West Highland White
Terrier, Pug, and Cocker Spaniel are considered to be at the highest
risk.
Dry eye occurs when the lacrimal (tear) glands are unable to
provide adequate moisture. There are several causes of dry eye in
dogs. Most cases are considered immune-mediated, where the
animal’s body destroys the glands because it sees them as foreign,
making the glands no longer capable of producing an adequate
amount of tears. However, destruction of the glands can also occur
secondary to infection, drug toxicity, or a problem with the nerve that
goes to the lacrimal gland.
To diagnose the condition, a Schirmer tear test is performed, which
involves placing a small strip of paper underneath the eyelid to wick
tears along the paper. The paper is left in place for one minute and
the distance the water line travels is measured. If the line does not
travel far enough, a diagnosis of dry eye is made.
Dry eye causes the eye to become irritated because the tears
normally lubricate and protect the eye. Dogs with dry eye often have
a red conjunctiva. Many also have a thick mucus discharge. Dogs with
this condition are more susceptible to eye infections and corneal
ulcers. With prolonged dry eye, the cornea may become scarred
and pigmented. Blood vessels invade the cornea as well. All of these
components lead to reduced vision, and eventually blindness may
occur.
In an effort to stimulate tear production, control secondary
infections, and decrease scarring, veterinarians often prescribe several
medications to treat all aspects of the disease process. One of the
cornerstones of therapy is an immune-modulating drug, a medication
that prevents the patient’s immune system from destroying the
glands. An additional benefit of these medications is that they help
reduce the number of blood vessels on the cornea and reduce the
severity of corneal pigmentation, allowing for better vision as the
cornea becomes clearer. Other medications suc