The
gland is contained within a fold of conjuctiva commonly called the "third
eyelid". Normally the lower pole of gland is anchored to the connective
tissue inside the bony orbital rim. In the abnormal eye, the inferior
ligament is absent or poorly developed. When the gland becomes inflamed and
swollen, it flips up from under the "third eyelid" and herniates from under
the lower eyelid, (see the figure below.)
Through repeated inflammation and herniation, this condition is
associated with the development of "dry eye" or kerato-conjunctivitis
sicca. Surgery can restore the gland to it's proper position. Removal of the
gland can precipitate "dry eye" and so should be avoided. Relatively small,
almond shaped eyes whose structures are well supported by the infraorbital
malar complex (cheekbones) are rarely subject to cherry eye. Breeders should
select stock with healthy eye conformation, and prospective owners should look
for a small almond eye when purchasing a puppy.
Occasionally the gland will swell and herniate acutely from allergy,
injury or infection. If your dog does develop a cherry eye, it is important to
reduce it as soon as possible to avoid drying and further injury which can
turn an acute herniation into a chronic one.
You can often replace the gland into it's normal position under the "third eyelid" membrane by a simple manual maneuver. While stretching the eyelid in a superior lateral direction, put gentle but firm pressure on the medial lower lid as indicated in the figure. This maneuver will generally work on cherry eyes that have been present for less than 24 hours, and are not very large or infected. Antibiotic drops should be used for about 48 hours following replacement of the gland.