In previous blogs we discussed the most common eye health problems our pets face. Today, we'll wrap up our five part series on eye health with the discussion of keratoconjunctivitis sicca (KCS). KCS is a fancy way of saying dry eye, and the hallmark of the condition is--yep, you guessed it--dry eyes!
Don’t shed a tear
We associate tears with sadness and sometimes extreme joy, but tears actually serve many purposes in the eye. They provide lubrication and contain antibacterial proteins, salts and oxygen. They are also quite effective at flushing away irritants.
Tears are made mostly of water. In fact, about 95% of the volume of tears is made of water. The rest is made up of oil and mucous. With KCS, there is a deficiency in the water portion of the tears.
There are several causes for KCS:
- Exposure to sulfa-drugs (this can be temporary or permanent)
- Immune-mediated - This is the most common cause of KCS and occurs when the immune system attacks the tear producing glands.
- Removal of the tear producing gland - This used to be a common surgery to repair cherry eye, but has fallen out of favor due to the potential for inducing KCS.
As I mentioned above, tears are 95% water and the remaining 5% is made up of oil and mucous. If you remove the water portion, you are left with a thick mucousy mess. This is probably the first symptom of KCS that you will notice. Your pet’s eye will have an increased amount of thick yellow discharge coating the eye and the membranes around the eye. Dry eyes are itchy, so you may also see your pet pawing at his eyes. In cases of chronic KCS, you will notice that the cornea, or surface of the eye, becomes dark in an effort to protect itself. This corneal pigmentation can lead to blindness.
It is usually relatively easy for your veterinarian to diagnose your pet with KCS. A test, called a Schirmer Tear Test, is perfomed to measure the amount of tears your pet produces. A thin strip of special paper will be placed in the corner of your pet’s eye for 60 seconds and allowed to absorb the tears your pet’s eye produces. After 60 seconds, the area of moisture is measured. If the length is less than 15mm, your pet has dry eye.
Treating KCS requires significant diligence. Having Petplan pet insurance, which covers chronic conditions such as dry eye, can allow you to focus on your pet's treatments instead of the veterinary bills. Topical ointments are used to suppress the immune-mediated destruction of the tear glands. In addition, products like artificial tears are used to provide relief from the dryness. Topical medications will need to be applied often throughout the day for the life your pet to prevent further damage to the eye. While it may seem tedious, it is important--these things will save your pet’s vision!
I hope you’ve enjoyed this journey down the road of common eye conditions. If you think your pet has symptoms of any of these conditions, schedule an appointment with your veterinarian. Eye health is important and early intervention in all of these conditions will make all the difference.