The Essential Role of
Tears in Healthy Eyes
More than just moisture, tears and the tear film support overall ocular health in a variety of ways. Under or over tear production can lead to various diseases and conditions. Tears help to:
Lubricate the cornea, eyelids and conjunctiva (the tissue that lines the eyelids)
Protect the eyes against infection
Provide oxygen and nutrients to the cornea
Remove metabolic by-products like carbon dioxide
Play a role in the local immune defense
Wash away irritating particles or foreign bodies
Keep the eye surface smooth and clear
The Essential Role of Tears in Healthy Eyes
More than just moisture, tears and the tear film support overall ocular health in a variety of ways. Under or over tear production can lead to various diseases and conditions. Tears help to:
Lubricate the cornea, eyelids and conjunctiva (the tissue that lines the eyelids)
Protect the eyes against infection
Provide oxygen and nutrients to the cornea
Remove metabolic by-products like carbon dioxide
Play a role in the local immune defense
Wash away irritating particles or foreign bodies
Keep the eye surface smooth and clear
What is Dry Eye?
Dry Eye is a common eye condition in dogs that occurs when their tear glands are not able to produce the normal amount of tears. The condition can be very painful because without tears, the eyes feel dry and irritated (feeling like sandy grit in the eye) and are more prone to infections and ulcers. If left untreated, this can lead to pigmentation changes and scarring of the eye surface and eventually even blindness.
Signs of Dry Eye
The appearance of Dry Eye can be varied and subtle, especially in the early stages. If your dog has any of the following signs, you should make an appointment with your veterinarian.
Blinking
Blinking or rubbing eyes excessively.
Trying to keep eyes closed
Redness
Bloodshot appearance
and inflammation
Discharge
Discharge from
the eyes
Dull appearance
Dull or
dry appearance
Conjunctivitis
Frequent conjunctivitis, eye infections
or corneal ulcers
Dark pigment
Dark pigment on the surface
of the eyes
Please note: the eyes of some dogs affected by Dry Eye look quite normal, despite severely reduced tear production and destruction of the tear glands. Being aware of the signs is a big step in getting it diagnosed early before too much tear tissue is destroyed and adverse changes to the eye develop. Veterinary specialists in ophthalmology recommend testing virtually all sore eyes for Dry Eye to make sure it’s caught early.
Predisposed Breeds
All breeds of dogs can develop Dry Eye at any age, but some are much more prone to the condition. Dog breeds particularly susceptible to Dry Eye include:
English Cocker spaniel
West Highland White terrier
Cavalier King Charles spaniel
Shih Tzu
Yorkshire terrier
Bulldog
Pekingese
Pug
Lhasa Apso
Veterinary specialists in ophthalmology recommend testing susceptible breeds regularly and many owners elect to proactively have their dog tested during routine appointments.
Diagnosing Dry Eye
Your veterinarian will perform a quick and painless test on your dog’s eyes called the Schirmer Tear Test. It involves placing a special strip of paper into the eye and holding it in place for 60 seconds to provide a measure of the amount of tears your dog produces in one minute. The test is typically done in both eyes because the findings can be quite different. Your veterinarian will assess these results, along with any other signs your dog is exhibiting, to determine if your dog has Dry Eye.
If your dog is not producing enough tears, treatment should be started immediately. The earlier the condition is diagnosed the more likely that treatment will be successful. If your dog has any of the signs listed above or is a breed at higher risk, talk to your veterinarian about testing or other ideas to help your dog.
1. PRESCRIPTION OINTMENT with cyclosporine: To treat the underlying condition, the veterinarian prescribes an eye ointment that protects the tear glands from being attacked by the immune system.
By the time Dry Eye is typically diagnosed, the gland destruction is so advanced therapy may be less effective. This means tear replacement drops that hydrate and lubricate the eye surface are often required.
Even in dogs that respond well to treatment with cyclosporine prescriptions, additional tear supplementation is still recommended to keep the eyes as comfortable and pain-free as possible.
2. DAILY TEAR REPLACEMENT: Considered an essential component in the management of Dry Eye to keep eyes lubricated, most veterinarians recommend lubricating drops that replace natural tears to keep the eyes moist and protected.
These are only supplemental and do not replace treatment with cyclosporine. However, the majority of cases will benefit from long-term use of tear replacement drops, in addition to cyclosporine, to keep the eyes as comfortable as possible.
