“Cherry Eye” is the common term for the condition in which the gland of the third eyelid suddenly protrudes from the eye or becomes prolapsed. The third eyelid, or nictitans, is a triangular-shaped structure lying beneath the lower eyelid. It is composed of cartilage for support and a gland that is important in tear production. A layer of conjunctiva (the pink tissue that surrounds the eye) covers the cartilage and the gland. The purpose of the third eyelid is to protect the eye and to aid in the production and distribution of tears.
Normally, the third eyelid gland is tucked away below the eye and is not noticeable. In some pets, the gland will suddenly prolapse upward, appearing as a reddish mass. When prolapsed, it usually becomes inflamed and swollen. There are many breeds of dogs that are predisposed to displacement of this gland (e.g. Cocker Spaniel, Beagle, Boston Terrier, Bulldog, Lhasa Apso, St. Bernard, and Mastiff). Burmese cats may be predisposed as well. There is also a tendency for cherry eye to affect both eyes, but usually not at the same time.
How are cherry eyes treated?
The goal of treating a cherry eye is to surgically restore the swollen gland to its normal position in order to preserve its ability to make tears. Repositioning rather than resecting (removing) the gland is recommended to prevent a decrease in tear production and a condition known as “dry eye.” There is approximately a 90% success rate in surgical repositioning of the gland, however, in some breeds (e.g. Bulldog and Mastiff), there is a greater tendency for the cherry eye to return. If the cherry eye does recur, a second surgery to replace the gland will be necessary.
Why should my pet have surgery?
If a cherry eye is left untreated, it can result in chronic irritation of the eye, infection of the prolapsed tissue, and/or dry eye due to a decrease in tear production by the prolapsed gland.