What is Cherry Eye?
All animals, including humans, have a third eyelid (nictitating membrane) located between the cornea and lower eyelid on the inner portion of the eye. In animals, the third eyelid is a movable protective structure which contains the third eyelid gland (nictitating gland). The third eyelid gland produces a significant portion of protective tear film for the eye, often referred as the precorneal tear film. Decreased production of the tear film results in secondary conjunctivitis and keratitis.
Defects during eye development allow the gland of the third eyelid to prolapse. Prolapsing of the third eyelid gland is often seen in young dogs under the age of two years and it is thought to have a genetic predisposition.
****Dogs have two tear-producing (lacrimal) glands in each eye. One is located in the upper lid, and one is the lower lid. The lower lid holds the nictitating membrane, which is a transparent or translucent lid that passes over the eye for protection and to moisten it while maintaining vision.*****Please Remove from the article!!!
The prolapse tends to occur on one eye, however it is not uncommon for it to develop on both eyes in certain dog breeds, such as English and French Bulldogs, Shar Peis, Great Danes, and Cane Corsos.
When prolapsed, a red mass or lump is noted at the inner corner of the eye and the surface can become red and inflamed. This is called a cherry eye or prolapsed nictitating gland.
*****Cherry eye is a prolapsed eye gland, specifically a prolapsed nictitating membrane. When a dog's third eyelid gets prolapsed or protrudes from the eye, you'll see a cherry-red lump in the corner of your dog's eye.***** Remove from article!!!
Symptoms of Cherry Eye
Exposure of this sensitive third-eye tissue often results in secondary inflammation, swelling, or infection. Cherry eye appears like a very red lump in the inside corner of the eye, or eyes if both are affected. Despite its angry, red appearance, this condition does not cause pain but can interfere with the normal tear production for that eye. This third eyelid gland is thought to produce approximately 30 percent of the tear production for the eye and contributes to the precorneal tear film. Dogs with the cherry eye often develop dry eyes, conjunctivitis, which can lead to (keratoconjunctivitis sicca).
*****Cherry eye occurs when the tear-producing gland swells or protrudes from the lid like a red, fleshy mass. When the gland protrudes, called eversion, the usually moist tissue is exposed to air and other irritations, like a paw. This can cause the interruption of blood supply to the gland.***** Remove from article!!!
Identifying and getting treatment for a dog with cherry eye is essential. Delaying treatment may lead to irreversible damage to the third eyelid gland and the corneal surface of the affected eye(s). Surgical replacement of the third eyelid gland is the treatment of choice. However, prior to surgery, medication can be used to alleviate the inflammation and/or resolve the secondary infections of the surrounding eye structures.
******You can treat cherry eye with medication or there are different types of surgery. Sometimes cherry eye will correct itself if you do nothing, although this is not often the case. If caught early, cherry eye may be resolved with a closed-eye massage of the affected eye or with antibiotics and steroids.***** Remove from article!
****Either way, topical medication can help reduce the inflammation and prevent or resolve the secondary infections that are commonly associated with the condition. ***** Remove from article!
If left untreated, this condition can lead to dry eye, conjunctivitis, keratoconjunctivitis sicca, and other complications.
Multiple surgical techniques exists for the correction of cherry eye, however you should consult with your veterinarian to determine the best method to correct the condition in your dog. The techniques available vary in efficacy due to complexity, breed conformation, effects on the mobility of the third eyelid, third eyelid gland function, and risks of complications or surgical failure.
*****One surgery to fix cherry eye is performed to create a pocket or envelope that requires suturing of tissue around the prolapse, encasing it in a layer of the conjunctiva, which is the lining of the white part of the eye. If surgery is recommended, this is usually the safest method with the highest success rate.****
****Another method, which is much harder to complete successfully, is to surgically reposition the eyelid, or anchor the eyelid to the globe of the eye. The biggest risk using this technique is a recurrence of the condition or the sutures causing a problem for the eye.**** Remove from article!
Please note, surgical removal of the third eyelid gland is not recommended to treat the condition.
****The preferred way vets used to treat cherry eye was to remove the tear gland, as this is a relatively simple and quick surgery. *****
The problem with the removal of the gland, especially in young dogs with many years ahead of them, is the development of chronic dry eye or keratoconjunctivitis sicca. As animals age, tear production decreases. Preserving the gland early in life benefits the dog in the senior years.
****Vets now recognize the importance of preserving the tear gland.**** Remove!
If surgical removal of the third eyelid gland is performed, the dog will require extensive ocular treatment for the rest of its life.
*****in some cases. If you choose to have the gland removed, it is likely that the dog will need to be treated several times daily with moisturizing eye drops for the rest of its life. Your veterinarian may do this surgery or refer your pet to a veterinary ophthalmologist. This is a veterinarian who has had advanced training and certification in ophthalmology, the branch of medicine concerning eye diseases. The American College of Veterinary Ophthalmologists is a good place to start your search for an eye specialist for your pet.**** Remove!
****Cherry eye is not preventable. It is most often seen in young dogs under the age of 2. The cause of cherry eye is not fully known but thought to be a weakness in the eyelid tissue that normally holds the gland in place. Genetics may play a role.
Some breeds, such as spaniels, shar-peis, bulldogs, beagles, Lhasa apsos, Shih Tzus, terriers, pugs, and bloodhounds have a higher incidence of this condition. While not preventable, if you notice redness, bring this to your vet's attention right away. You may be able to prevent the gland from developing into a complete prolapse.**** Remove!
White C, Brennan ML. An Evidence-Based Rapid Review of Surgical Techniques for Correction of Prolapsed Nictitans Glands in Dogs. Vet Sci. 2018;5(3):75. Published 2018 Aug 23. doi:10.3390/vetsci5030075
Edelmann ML, Miyadera K, Iwabe S, Komáromy AM. Investigating the inheritance of prolapsed nictitating membrane glands in a large canine pedigree [published correction appears in Vet Ophthalmol. 2014 Mar;17(2):156]. Vet Ophthalmol. 2013;16(6):416-422. doi:10.1111/vop.12015