Disorders of the Eyelids in Dogs
Problems affecting the eyelids may be congenital (present at birth) or may occur as a result of injury, infection, or exposure to various types of irritants.
Entropion is the turning in of the edges of the eyelid so that the eyelashes rub against the eye surface. It is the most frequent inherited eyelid defect in many dog breeds. It may also follow scar formation and severe involuntary winking due to pain in the eye or the surrounding area. The turning in of eyelashes or facial hairs causes discomfort and irritation of the conjunctiva and cornea. Extremely long lashes can cause scarring, abnormal coloring, and possibly the formation of slow-healing sores on the cornea.
Early spasms of entropion may be reversed if the cause is removed or if pain is lessened. Turning the lid hairs back away from the eye with stitches in the lid, injections of medication into the lid close to the area where the lid is turning in, or using anesthetics to block the nerves in the eyelids are some of the methods that have been used to lessen the pain. Established entropion may require surgery to correct the defect.
Ectropion is a slack eyelid edge that is turned out, usually with a large notch or “crack” in the eyelid. It is a common abnormality affecting both eyelids in a number of dog breeds, including the Bloodhound, Bull Mastiff, Great Dane, Newfoundland, St. Bernard, and several Spaniel breeds. Developing scars in the eyelid or facial nerve paralysis may produce ectropion in one eyelid in any species. Exposure of the conjunctiva to environmental irritants and secondary bacterial infection can result in longterm or recurrent conjunctivitis (inflammation of the conjunctiva). Topical antibiotics may temporarily control infections, but surgical lid-shortening procedures are often necessary to resolve the condition. Repeated, periodic cleansing of the affected eyelid with mild decongestant solutions can control mild cases. To protect your pet’s eyesight, follow your veterinarian’s treatment program carefully.
Lagophthalmos is an inability to fully close the eyelids and protect the cornea from drying and trauma. It may result from extremely shallow orbits, a common condition in breeds with short, broad, flattened heads (brachycephalic breeds such as Bulldogs and Pugs, for example). It may also be caused by an abnormal protrusion of the eyeball due to a mass in the eye socket, or facial nerve paralysis. Scarring, abnormal coloring, and the formation of slow-healing sores of the cornea are common problems with this condition. Unless the cause can be corrected, treatment involves frequent use of lubricating ointments and surgical shortening or closure of the corners of the eye either temporarily or permanently. Excessive nasal skin folds and facial hair may aggravate the damage caused by lagophthalmos.
Abnormalities of the eyelashes include extra eyelashes or misdirected eyelashes on the edge of the eyelid. These conditions may cause watering eyes, development of blood vessels in the cornea, and slow-healing sores and scarring in the cornea. In many instances, irregular eyelashes are very fine and do not cause signs of irritation or damage the eye. However, eyelashes in an unusual position sticking out through the back of the eyelid can cause profound pain. If the extra lashes cause damage to the cornea or conjunctiva, it may be necessary to surgically cut out or freeze and remove the eyelash follicles. Irregularities of the eyelashes are common in some dog breeds and are probably inherited.
Inflammation of the eyelids can result from the spreading of a generalized inflammation of the skin, inflammation of the conjunctiva, local glandular infections, or irritants such as plant oils or sunlight. Fungi, mites, or bacteria can infect the eyelids, which can then lead to a generalized inflammation.
Lesions of immune-mediated diseases can occur where the skin and conjunctiva join. Pemphigus is an example of a disease in which large blisters occur on the skin and mucous membranes. Pemphigus is often accompanied by itching or burning sensations. Skin scrapings, cultures, and biopsies may be required for an accurate diagnosis. Localized glandular infections may be short-term (for example, a stye) or longterm (for example, a meibomian abscess).
When inflammation of the eyelids is caused by a generalized condition, whole-body therapy often is necessary in addition to treatment of the eye itself. Supportive therapy of hot packing and frequent cleansing is often used in severe cases. Your veterinarian will recommend a treatment program designed to control the generalized condition, make your pet more comfortable, and treat the eye condition. Be sure you thoroughly understand the treatment program your veterinarian recommends. Do not hesitate to ask for detailed instructions regarding any eye drops or other medication you will need to give to your pet. It is often helpful to have the veterinarian demonstrate the administration of these medications.