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 such as topical antibiotics
may be used, especially if there is a concurrent corneal ulceration or
scratch on the eye. Topical steroids are chosen in some cases to help
with the redness, discharge and corneal scarring. Artificial tear gel
is extremely important in the management of dry eye, as replacing
tears and keeping the eye moist can help minimize the risk of further
eye problems. Finally, in cases where the nerve that stimulates tear
Pittsburgh Veterinary Specialty
& Emergency Center
production has been damaged, an eye drop, generally placed onto
the food, can help improve nerve function.
In cases of dry eye that do not respond to the above treatments,
surgery may be recommended. A parotid duct transposition (PDT) is
a surgery that can help improve tear production. In this procedure,
the duct from one of the salivary glands is moved from the mouth
to the eye, so that when saliva is delivered from the gland, it helps
to moisten the eye as a tear replacement. This surgery is generally
considered a last resort for patients whose dry eye continues to
persist despite being appropriately treated. Even after a PDT, patients
still require ongoing medical therapy.
Frequent rechecks with a veterinarian are recommended to
continue to monitor the dry eye and response to therapy. Routine
monitoring of the Schirmer tear test as well as regular fluorescein
staining to monitor for corneal ulcerations are required for patients
with dry eye. Dry eye generally requires medical management for the
duration of the dog’s life.
1
2
3
Figure 1: Redness of the conjunctiva around the eye as well as a few corneal blood
vessels and mild brown pigmentation on the cornea in a dog with early dry eye.
Figure 2: Severe corneal pigmentation and discharge in a dog with chronic,
untreated dry eye.
This Industry Insight was written by Kara Gornik, DVM, DACVO, Ophthalmology
Specialist, Board Certified in Veterinary Ophthalmology
On the Job
Always interested in veterinary medicine, Dr. Kara Gornik decided to become an
ophthalmologist after receiving a research grant in veterinary school to study
immunologic receptors in equine eyes. She is published in a number of professional
journals and has spoken at many conferences and continuing education events. Her
particular clinical interests include golden retriever pigmentary uveitis, the genetics
related to ocular conditions, and inherited retinal conditions.
Education
Diplomate, American College of Veterinary Ophthalmology
Residency, Ophthalmology, Tufts University, Medford, MA
Fellowship, Comparative Ophthalmology, Michigan State University, East Lansing
Internship, Small Animal Medicine & Surgery, Michigan State University, East Lansing
Doctor of Veterinary Medicine, University of Georgia, Athens
Bachelor of Science, West Virginia University, Morgantown
South Hills location: 1535 Washington Road, Washington, PA 15301, 724.809.2000
North Hills location: 807 Camp Horne Road, Pittsburgh, PA 15237, 412.536.5248
Web site: PVS-EC.com
UPPER ST. CLAIR
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FALL 2018
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