What is dry eye?
Dry eye, also known as keratoconjunctivitis sicca or KCS, is a debilitating disease which can lead to blindness. It is very common and affects around 5% of all dogs. There are a number of breeds which are prone to this condition, for example Cocker Spaniels, West Highland White Terriers, Cavalier King Charles Spaniels, Shih Tzus, Bulldogs and Pugs.
The disease is caused by the body mounting an immune response against the tear glands, reducing and eventually stopping tear production altogether. In the early stages of the disease there may be no obvious problem, however later stages will lead to signs such as:
- red, inflamed eyes
- thick discharge from the eyes
- eye pain (the dog may hold the eyes shut or rub at the eyes)
- dark pigmentation of the surface of the eye
How is dry eye diagnosed?
Early detection and treatment is important as once the tear gland has been completely destroyed there is no going back. Diagnosis is very quick and simple and involves a special small strip of paper being placed over the lower eyelid which contains a dye which marks the amount of tear production in 60 seconds.
How is dry eye treated?
Treatment is three-fold:
- Preventing further destruction of the tear gland – the most effective treatment is a ciclosporin ointment applied to the surface of the eyes (usually twice daily). Gloves must be worn when applying this. Regular check ups with your vet are important to ensure the medication is working adequately.
- Lubricating the eye – once the condition is under control this may no longer be necessary but in the early phase of treatment, providing artificial lubrication will help to reduce discomfort and infections. There are various products on the market but ones designed for dogs are best as they are generally longer-lasting. Human artificial tears can be used but need very frequent application.
- Treating secondary infections – infections and ulcers are common in dogs with dry eye so treating these with a topical antibiotic is an important part of treatment in the early stage if infection is present.
Dry eye is not a curable condition and life-long treatment will be required.
In severe cases, surgery can be performed which diverts one of the salivary ducts into the eye so that saliva is used for lubrication instead of tears (a parotid duct transposition). When the surgery is successful, there is often no further treatment required. The dog will often have facial staining of the face as there will be overflow of saliva down the face, particularly at mealtimes when saliva production is increased.