What is cherry eye?

What is the gland of the third eyelid?

The gland of the third eyelid (nictitans gland) is located on the inner surface of the third eyelid (nictitating membrane) and produces roughly 25% of the tear film.

When does it prolapse?

Prolapse of this gland occurs primarily in young dogs and is caused by laxity of the connective tissue. A reddish swelling appears in the medial canthus (inner corner of the eye). The condition is also commonly known as "cherry eye."

Why does it not resolve on its own?

Once the gland prolapses, it becomes edematous, so it often can no longer return to its original position.

What problems does cherry eye cause?

The prolapse impairs the blood supply of the gland, and over time the glandular tissue itself is damaged. In the long term, this can lead to necrosis of the glandular tissue and consequent keratoconjunctivitis sicca (dry eye disease). In certain breeds, e.g. the English bulldog, prolapse of the gland is more common because of their lax connective tissue.

What can be done?

The gland must always be repositioned to its original location. Removing it is a professional error and leads to keratoconjunctivitis sicca (dry eye disease).