Veterinary care includes diagnostic tests and subsequent treatment recommendations. Diagnosis In-depth
It is important to inform your veterinarian of all the medications your cat is currently taking because KCS may be an uncommon side effect associated with some medications. Diagnosis usually includes the following: Examination of the eye including a thorough evaluation of the eyelids, conjunctiva and cornea
Schirmer Tear Test. This test measures tear production. Normal tear production is usually more than 10 mm/min. Caution should be used when interpreting this test. When cats are stressed (such as riding in a car to the veterinary clinic), their tear production tends to decrease. This can make interpretation of low results difficult. The test may need to be repeated several times to demonstrate consistently low values (less than 5 mm/min.) in order to confirm a diagnosis of KCS.
Fluorescein stain. The dye is applied to the cornea to check for the presence of a corneal ulcer.
Culture of discharge. A culture may be submitted if a secondary bacterial infection is suspected.
Viral assays. Scrapings of the conjunctiva may be taken to submit to special laboratories to try and identify the presence of feline herpesvirus. Confirming an active infection of this virus can be difficult. The virus has the ability to become latent or quiet, leading to negative test results.
Routine blood work. Your veterinarian may recommend blood tests including a complete blood count and serum biochemistry profile if an underlying disease is suspected.
Treatment is aimed at increasing tear production, applying artificial tears, and reducing any bacterial infections or inflammation .
When using eye medications, be sure to ask your veterinarian whether the medications can be administered at the same time, or whether they should be separated by several minutes. Some medications can be administered together; others need to be administered alone. In general, drops are applied prior to ointments, and no more than two medications are given together at one time.
Application of 0.2% cyclosporine ointment can be tried in the cat to increase tear production. Cats do not always tolerate topical cyclosporine, and the ointment is not always commercially available. When the cat does tolerate it and tear production does improve with the drug, it must be used on a long-term basis.
Oral pilocarpine drops have been tried in the past to increase tear production, but they are not usually recommended in the cat because they do not work well and commonly produce side effects (salivation, vomiting, diarrhea).
In most cats with KCS, artificial teardrops and ointments are the primary agents used to combat their dry eye. This is particularly true in cats that do not tolerate or do not respond tocyclosporine. Drops provide moisture and ointment provides lubrication to the surface of the eye.
Antibiotic drops or ointment may be used if a secondary bacterial infection or a corneal ulcer is present.
Corticosteroid drops or ointment may be used to decrease inflammation. These medications are only used after fluorescein staining of the cornea has determined that there is no ulceration present. Corticosteroids cannot be used in the presence of a corneal ulcer because they delay healing.
Occasionally topical anti-viral medications may be tried for herpesvirus. These medications are expensive, must be applied frequently throughout the day, and it is not known how beneficial they are in the treatment of KCS in the cat.
In severe cases of KCS that do not respond to medications, surgery may be performed in which the opening of a salivary duct is moved from the mouth to the eye. This results in saliva flowing over the eye to keep the eye moist. It is not an ideal treatment for KCS because saliva is not the same as tears, and the flow of saliva cannot be controlled very well. The surgery is helpful, however, for those cats that remain persistently painful and squinty despite trying all forms of medical therapy.