Overview

• Eversion or rolling out of the eyelid margin, resulting in exposure of the palpebral conjunctiva.
• Ophthalmic system (exposure and poor tear retention/distribution-may predispose patient to irritation, recurrent infections, and sight-threatening corneal disease).

Signalment

• Dogs, seldom cats.
• Breeds with higher than average prevalence-sporting breeds (e.g., spaniels, hounds, and retrievers); giant breeds (e.g., Saint Bernards and mastiffs); any breed with loose facial skin (especially bloodhounds).
• Developmental-genetic predisposition in listed breeds; may occur in dogs <1 year old.
• Acquired-noted in other breeds; occurs late in life secondary to age-related loss of facial muscle tone and developing skin laxity.
• Intermittent-caused by fatigue; may be observed after strenuous exercise or when drowsy.

Signs

• Eversion of the lower eyelid with lack of contact of the lower lid to the globe and exposure of the palpebral conjunctiva and third eyelid-usually obvious.
• Facial staining caused by poor tear drainage-tears spill over onto the face instead of passing from the eye to the nose via the nasolacrimal ducts.
• History of mucoid to mucopurulent discharge owing to conjunctival exposure.
• Recurrent foreign body irritation due to debris localizing between lid and globe in inferior cul-de-sac.
• History of bacterial conjunctivitis.

Causes & Risk Factors

• Usually secondary to breed-associated alterations in facial conformation and eyelid support.
• Marked weight loss or muscle mass loss about the head and orbits-may result in acquired disease.
• Tragic facial expression in hypothyroid dogs.
• Scarring of the eyelids secondary to injury or after overcorrection of entropion-may result in cicatricial disease.

Differential Diagnosis

• Usually clinically obvious.
• Look for any underlying disorder in non-predisposed breeds and patients with late-age onset.
• Loss of orbital or periorbital mass-may cause condition in patients with masticatory myositis.
• Palpebral nerve paralysis-condition associated with lack of muscle tone of the orbicularis oculi muscles.

CBC/Biochemistry/Urinalysis

N/A

Other Laboratory Tests

• Possible masticatory myositis-test for auto-antibodies against type 2M muscle fibers.
• Palpebral nerve paralysis or tragic facial expression-consider testing for hypothyroidism.

Imaging

N/A

Diagnostic Procedures

• Palpebral nerve paralysis-full neurologic evaluation; potential for hypothyroidism.
• Secondary conjunctivitis-consider bacterial culture or cytologic examination to help select an appropriate topical antibiotic.
• Fluorescein or rose bengal staining of the cornea and conjunctiva-may document corneal ulcerations; may reveal severity of the exposure problem.

Drug(s)

• Topical broad-spectrum ophthalmic antibiotics-bacterial conjunctivitis or corneal ulceration. Neomycin/polymyxin B/bacitracin (or others based on bacterial culture and sensitivity) q6–8h.
• Lubricant eye drops and ointments-reduce conjunctival and corneal desiccation secondary to exposure.
• Hypothyroid and masticatory myositis-induced conditions-may respond well to appropriate medical treatment of the underlying disease.

Contraindications/Possible Interactions

N/A

Associated Conditions

• Hypothyroidism
• Myopathy, focal

Inflammatory-masticatory myositis and extraocular myositis

Age-Related Factors

Old animals more likely to have ectropion secondary to loss of facial muscle tone.

See Also

• Hypothyroidism
• Myopathy, Inflammatory–Masticatory Myositis and Extraocular Myositis

Author J. Phillip Pickett

Consulting Editor Paul E. Miller