Excerpt from Ask the Vet About Dogs: Easy Answers to Commonly Asked Questions

Cherry eye is the common term for a condition in which a bit of a gland that is normally anchored beneath the third eyelid—that band of white tissue sometimes visible in the inner corner of your dog’s eye—becomes enlarged and slips out (prolapses) from beneath the third eyelid. You will see a pink bulb at the inner corner of your dog’s eye, and the entire eye may be somewhat red and irritated. As the gland becomes swollen and dried out, it begins to look even worse.

The condition usually occurs in young dogs (six months to two years) and several breeds are particularly susceptible, including cocker spaniels, bulldogs, beagles, bloodhounds, Lhasa apsos, shih tzus, and any brachycephalic breeds (those with short, flat faces). Cherry eye can occur in only one eye or in both. The condition can be very uncomfortable for your dog. Older dogs may develop cancer of the gland of the third eyelid, so a biopsy should be taken to differentiate between cherry eye and cancer.

Some dogs seem to have no problem with cherry eye, but the best treatment is surgical repair. Historically, veterinarians have simply removed the enlarged, prolapsed gland, but we now realize that up to 50 percent of the tears produced to lubricate the eye are produced by the gland, and removing it makes the dog susceptible to decreased lubrication of the eye as she becomes older. Surgical repair consists of pushing the gland back under the third eyelid and sewing it in place.

Your veterinarian may prescribe drugs to reduce inflammation of the eye before or after surgery and suggest that your dog wear an Elizabethan collar to prevent her from rubbing the eye until it has healed. The surgery can be quite tricky, and an estimated 5 to 20 percent of cherry eyes reoccur after the surgery. When this happens, veterinary ophthalmologists recommend that the procedure be performed again, with the hope of salvaging this important gland.