Nictitans Gland Replacement (“Cherry Eye” Surgery)
A prolapsed gland is the most common disorder of the third eyelid in dogs. It is commonly referred to as a cherry eye because the prolapsed gland appears as a red mass that protrudes from behind the third eyelid. Prolapsed gland of the third eyelid is more common in young dogs and is overrepresented in some breeds, including American cocker spaniels and English bulldogs.
The exact cause of this condition is unknown, but it is thought to be due to a weakness of the tissues that normally anchor the gland to the periorbita. The condition may be unilateral but is often bilateral, with the glands prolapsing at different times.