Conjunctivitis (Cherry Eye)
By Dr. Karen Burgess

What is a “cherry eye” technically?
A cherry eye or “haw” as it is often called occurs when a dog’s third eyelid gland prolapses or pops out.  The third eyelid is the pink fleshy tissue seen toward the middle of the lower eyelid.  Instead of moving up and down like upper and lower eyelids, the third eyelid moves from side to side, or from nose to ear.  The third eyelid serves as an extra layer of protection for the eye.  The gland of the third eyelid that is affected by cherry eye produces an important portion of the eye’s protective tear film.

Why do dogs develop cherry eye?
The third eyelid gland is normally firmly attached to the lower portion of the eye.  For unknown reasons, in particular in some breeds, there is weakening of this attachment causing it to pop out.  Over time, the now malpositioned gland becomes inflamed and swollen, making it more difficult for it to stay in its proper position.

What does a cherry eye look like?
What most owners notice with a cherry eye is a red swollen mass like appearance protruding from on the nose side of the eye.  Cherry eye is typically not painful.  They can vary in size and in some cases will come and go.

What are treatment options for cherry eye?
Definitive treatment involves surgically tacking the prolapsed third eyelid gland back in place.  This surgery involves a high degree of technical skill for best chances of success and should be performed by and ophthalmologist (veterinarian that has received advanced training in ocular disease and surgery).  There is another surgical procedure that involves removing or amputating the third eyelid gland.  This is not recommended and can lead to lifelong complications with tear production and thus a potentially painful and non-visual eye.  In some cases, use of a topical steroid and gentle external massage can pop the proptosed gland back in place.  In some milder cases this can be done at home by owners as needed for temporary control.

What is cherry eye’s prognosis?
With surgical treatment performed by an ophthalmologist the prognosis is good.  In some cases (up to 20%) additional surgery may be required, thus making it that much more important to have a skilled person doing the surgery from the beginning.  Untreated cherry eye can eventually damage the cornea, affect vision, and become painful for the pet.