PROTRUSION OF THE GLAND OF THE NICTITANS MEMBRANA (“CHERRY EYE” )
The canine eye contains a structure not present in the human eye called the nictitans membrana (third eyelid). It is a large fold of conjunctiva that can pull up to cover the eye when it is irritated or injured. The third eyelid also contains the nictitans gland, which is normally located under the lower eyelid. “Cherry eye” is a common term for the condition where the gland of the nictitans membrana protrudes from its normal position in the eye.
The gland loses its normal position due to a weakness in the connective tissue that holds the gland in place. This condition is known as “cherry eye” because the gland is visible as a pink bulge in the comer of the eye. The American Cocker Spaniel, Beagle, Bloodhound, Boston Terrier, Bull Terrier English Bulldog, Lhasa Apso, St. Bernard, and Shar Pei are a few breeds that are genetically predisposed to this condition.
The nictitans gland should not remain in an abnormal position because it can lead to excessive tearing (epiphora), increased mucous discharge, and conjunctivitis It is, however, not adequate to remove the gland from the eye. The nictitans gland has an important lacrimal (tearproducing) function and removal of the gland can contribute to the development of Dry Eye Disease Keratoconjunctivitis sicca or KCS) as well as worsen the condition of pets that are already diagnosed with KCS. The American Cocker Spaniel, Lhasa Apso, and English Bulldog are a few breeds that are predisposed to both “cherry eye” and Dry Eye Disease.
Surgical replacement of the nictitans gland is the only treatment that will successfully correct this problem. Pending a standard preoperative workup (physical examination, hemogram), general anesthesia is necessary to reposition the gland. An incision is made through the conjunctiva that lies over the gland, and the gland is then positioned into the incision. To anchor the gland in place, two sutures are placed over the gland in such a way that when they are tied, the gland is inverted and held in a pocket of conjunctiva. This surgery is done on an outpatient basis, and the results are immediately apparent. Postoperative care is minimal, including topical and oral antibiotic therapies. Follow-up involves one postoperative recheck, which is included in the surgery fee.