Cherry Eye

 Pet Tales

 by Barry B. Burtis D.V.M.

Cherry Eye (Prolapsed Gland of the Third Eyelid)

I had just arrived for work, early one morning, when our receptionist told me there someone on the telephone, calling from Saudi Arabia, who wished to speak with me. It was the first time in my career that I began the day with a consultation from that far away.

The lady on the phone was a client who was working in the Middle East. Her 7 year old cocker spaniel, Chloe, was having a problem with its eye. She told me that a small, red, oval-shaped lump had suddenly appeared in the corner of Chloe's eye. The eye was weeping a bit, but, it did not seem to be bothering Chloe much otherwise. In all other ways, Chloe was acting just like normal. 

Diagnosing medical problems over the telephone is fraught with danger. It is just very hard to replace a "hands on " check up. You usually need to see the patient in person. Do a complete physical examination, look at the specific problem but also make sure there is no evidence of changes elsewhere in the body that might be influencing the primary condition. However, if ever there is a condition you can be pretty sure about without actually seeing the patient, it's the problem that Chloe had. I suggested it would be a good idea to have a local veterinarian confirm it, but my diagnosis was that Chloe had a   "cherry eye". The proper medical term for this condition is a prolapse of the third eyelid gland.

Dogs and cats, as well as other animals, have a third eyelid, in addition to an upper and lower eyelid. It is a protective structure that lies between the cornea and the lower eyelid in the corner of the eye nearest the nose. The third eyelid has three important functions, it produces fluid for the tear film, it helps distribute tear film across the cornea and it protects the cornea.

At least 50% of the aqueous tear film is actually produced by the third eyelid gland. This gland is located on the inside or the side nearest the eye of the third eyelid. Normally it is anchored by a band of tissue to deeper parts of the orbit of the eye. In several breeds of dogs and cats, this attachment is weakened. This allows the gland to evert or pop out of its normal position. When this happens, the eye looks different and the exposed gland will become more swollen, irritated and inflamed.

The problem occurs most commonly in young dogs (between 6 months and 2 years of age) of the following breeds: cocker spaniel, bulldog, beagle, bloodhound, lhasa apso, shih tzu and other short-nosed breeds. It happens less commonly in cats but does occur in Persians and Burmese. The problem can affect one or both eyes at the same or different times.

When the condition affects an animal, surgical correction is recommended. The gland should not just be surgically removed, as was sometimes done in the past. Animals that have the gland removed are at increased risk to develop dry eye, a problem resulting from insufficient tears, later in life.  There are several different surgical procedures that have been developed to treat the problem. They all involve some method to replace the gland in its normal position and attach it there. Often anti-inflammatory eye medications are used before and after surgery to lessen swelling of the gland.

Chloe has since had just such a surgical procedure to correct her problem. Her big brown eyes are just as beautiful as ever and her tear production is just fine, thank-you.

(PT 114)