Life without vision is unimaginable. A simple looking redness in your dog’s eye can lead to permanent blindness in your pooch. Here’s more on this eye disorder.
Keratoconjunctivitis Sicca (KCS) is a disorder of the tear glands that results in insufficient aqueous tear production and may lead to permanent blindness in your pet. It is also known as ‘Dry Eye Condition’.
Dry eye is prevalent in some breeds of dogs like Lhasa Apso, English Bulldog, American Cocker Spaniel, English Springer Spaniel, Pekingese, Pug, Chinese Shar Pei, Yorkshire Terrier, Shih Tzu, Miniature Schnauzer, German Shepherd, Doberman Pinscher and Boston Terrier.
Causes of KCS
There are multiple causes of KCS. Most common cause is the body’s own immune system causing abnormal inflammation of a lymph node or gland. Some other causes include tear secretory disorders that are mostly congenital (genetic) in origin. Certain drugs/anaesthetics can produce either temporary or permanent KCS. Removal of third eyelid to correct a disease problem can increase the risk of a dog developing KCS, since tear-production is associated partially with the third eyelid. The most common viral disease in dogs, canine distemper virus, is often associated with KCS. Systemic metabolic diseases associated with the development of KCS include hypothyroidism, diabetes mellitus, hyperadrenocorticism (Cushing’s Disease), atopy and dysautonomia. Damage to facial nerve, either due to disease or trauma, can result in KCS by decreasing the amount of tear film produced.
Diagnosis of KCS
Your dog will not develop this condition overnight. He will surely give you alarm. Dogs may have red/irritated/itchy eyes and may have a thick ocular mucoid discharge that can range from off-white to green in colour. The third eyelid is protruded, and the cornea is no longer shiny in appearance. In advanced cases, it may lead to potential vision loss.
Dry eyes need to be differentiated from different eye disorders. Schirmer Tear Test (STT), fluorescein staining of the cornea, and evaluation of the intraocular pressures are routine tests performed by a vet to diagnose if dog is suffering with eye problem. The Schirmer Tear Test is designed to measure amount of tear produced by the eye. It is a painless and very simple procedure. Schirmer Tear Test strips are available in pet clinics. This strip is a piece of paper with small scale on it. Vet will hold this strip touching to dog’s eye for a minute so that the tear production can be quantified, based on mm/min.
Schirmer Tear Test
Normal: ≥ 15 mm/min
Early KCS: 11-14 mm/min
Mild/moderate KCS: 6-10 mm/min
Severe KCS: ≤ 5 mm/min
Fluorescein is a bright yellow/orange stain that is used to detect corneal ulceration. In dogs with KCS chronic irritation to eye may lead to corneal ulceration. Tonometer can be used to measure pressure in eye.
Treatment of KCS
After confirmation of KCS in dog, it can be treated very effectively by using topical ophthalmic preparations. All therapies to treat Dry Eye Condition are very economical. It is the responsibility of the pet parent to remain alert and check if your dog is showing any symptom of developing this condition.
(Dr Bipin Sonar, Medical Services, SAVA Healthcare Limited, Pune.)