Entropion in Cats
Dr. Rhea Morgan
Entropion is an inward rolling of the eyelid edges. It is an uncommon problem in the cat, but when it does occur it usually affects the lower eyelids. Tearing
Unlike the dog, inherited entropion of a young animal is uncommon in the cat. Occasionally inherited entropion of the lower lid is present in purebred cats that have short, round faces, such as the Persian and Burmese.
Entropion in the cat is more likely to develop later in life secondary to other changes around the eye. One of the more common causes is spasm of the eyelid that occurs from the pain associated with corneal ulceration. In adults cats that acquire entropion, infections and inflammation with feline herpesvirus have been incriminated as a precipitating causes of this problem.
Secondary entropion may also occur when the eye itself moves backwards into the orbit (enophthalmos), or when the eye becomes shrunken following a severe injury or infection. Occasionally entropion develops following loss of normal neurologic function of the eyelids.
Entropion can occur alone, or may be accompanied by other eye problems such as abnormal eyelashes, corneal ulcers and scarring, and conjunctivitis. Since entropion is the inward rolling of the eyelid, the hair on the affected lid continuously rubs against the cornea. This can cause significant discomfort and trauma to the cornea.
Entropion most often affects the outer aspect of the lower eyelids of one or both eyes. The upper eyelids are rarely involved. In the flat, round-faced breeds of cat, the lower eyelids closest to the nose may be affected.
What to Watch For
Squinting, inability to see the eye well
Mucoid or thick discharge from the eyes
Redness and swelling of the conjunctiva, the inner lining of the eyelids
Rolling of the eyelid and wetness on the hairs adjacent to the eyelids
Diagnosing entropion is done by a thorough ocular examination.
The position of the eyelid is often assessed before and after the application of a local anesthetic solution.
Fluorescein dye is used to detect any corneal ulcers that may be present due to the constant rubbing of the eyelashes against the cornea. Fluorescein adheres to damaged sections of the cornea and appears bright green.
Other components of the eye are also examined to search for underlying causes of the entropion.
In some cats, testing for herpesvirus, other viruses and bacteria made be done from samples taken from the eye.
In cats with inherited entropion and in most cats with secondary entropion, surgery is required to roll the eyelid outward. An important part of surgical correction of entropion is to make sure your veterinarian has experience in this procedure. Overcorrecting entropion can have serious repercussions. The eyelid may then roll excessively outward or may not be able to close completely. Both these complications can result in irritation of the cornea, and may require either further surgery or a lifetime of protective eye medications.
Entropion repair in the cat may need to be repeated if future corneal or conjunctival irritation results in new episodes of spasm.
Prior to surgery any underlying corneal or conjunctival disease is treated. With resolution of pain and healing of a corneal ulcer, it is possible for spastic entropion to resolve.
Ancillary and temporary measures that can sometimes be used are eyelid "tacking" procedures or the insertion of a bandage contact lens between the painful cornea and the eyelids. The temporary tacking procedure involves placing sutures in the affected eyelid to pull the eyelid outward. These sutures usually remain in place for 7 to 10 days, or until the corneal pain resolves. A contact lens provides a transparent bandage over the diseased cornea to help it heal, and to prevent temporarily the eyelid hairs from rubbing against the cornea. If the entropion persists despite these procedures, then surgical correction is indicated.
The most common surgical technique used to correct entropion in the cat is the removal of an elliptical piece of skin from the eyelid, near the eyelid margin. When the incision is sutured closed, the eyelid is rolled outward. The goal of surgery is to return the lid to a more normal position and to keep the hairs of the eyelid from rubbing on the cornea.
Home Care and Prevention
Home care associated with entropion usually involves administering medication for corneal ulcers. After surgery is performed your cat will usually be sent home with an Elizabethan collar to prevent him from pawing or rubbing at the eyes. Keep this collar on your pet at all times. Examine your cat's eyes frequently and make sure there is no evidence of excessive tearing or pain (squinting). Frequent rechecks may be necessary to make sure the eyes continue to heal properly.
Sometime, topical antibiotics are prescribed. Administer the medications as instructed and inform your veterinarian if you are having trouble medicating your pet. Sutures are typically removed in 10 to 14 days.
If corneal damage has occurred, repeated examinations by your veterinarian can help determine if your pet is improving or needs additional treatment.