Pittsburgh Veterinary Specialty & Emergency Center
INDUSTRY INSIGHT
VETERINARY SERVICES
SPONSORED CONTENT
DRY EYE IN DOGS
Kara Gornik , DVM , DACVO Ophthalmologist at Pittsburgh Veterinary Specialty and Emergency Center ( PVSEC )
Keratoconjunctivitis 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
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 .
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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
Pittsburgh Veterinary Specialty & Emergency Center
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
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