Ophthalmology · Eyelid Disorders
The facts most likely to be tested
Entropion is the inward turning of the eyelid margin, most commonly affecting the lower eyelid.
The most common etiology is involutional (age-related) due to horizontal eyelid laxity and weakening of the lower eyelid retractors.
Patients present with foreign body sensation, tearing (epiphora), and conjunctival injection caused by trichiasis (eyelashes rubbing against the globe).
Chronic mechanical irritation from eyelashes leads to corneal abrasion, ulceration, and potential scarring if left untreated.
Physical examination reveals the inversion of the eyelid margin, which can often be exacerbated by having the patient forcefully close their eyes.
Initial management for symptomatic relief includes lubricating eye drops and taping the eyelid to the cheek to pull the margin outward.
The definitive treatment for persistent or severe cases is surgical correction to tighten the eyelid retractors and horizontal eyelid support.
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A 78-year-old male presents to the clinic complaining of a persistent 'gritty' sensation and excessive tearing in his right eye for the past three months. On physical examination, the lower eyelid margin is inverted, with several eyelashes rubbing against the bulbar conjunctiva. The patient is asked to squeeze his eyes shut, which causes the eyelid margin to rotate further inward. A fluorescein stain reveals punctate epithelial erosions on the inferior cornea.
What is the most appropriate definitive management for this patient?
Surgical correction
The patient presents with classic signs of involutional entropion causing trichiasis and corneal abrasion; while lubricants provide temporary relief, surgical tightening of the eyelid is the definitive treatment.
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Etiology / Epidemiology
Primarily affects elderly patients due to age-related horizontal eyelid laxity and orbicularis oculi weakness.
Clinical Manifestations
Inward turning of the eyelid margin causing trichiasis (eyelashes rubbing against the cornea).
Diagnosis
Diagnosis is clinical; perform a snap-back test to assess eyelid laxity.
Treatment
Temporary relief with lubricating drops; definitive treatment is surgical correction.
Prognosis
Untreated cases lead to corneal ulceration and permanent vision loss.
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Epidemiology & Etiology
Entropion is most common in the geriatric population due to involutional changes. Secondary causes include cicatricial scarring from chemical burns, trachoma, or previous ocular surgery. It is characterized by the inward rotation of the eyelid margin against the globe.
Pertinent Anatomy
The lower eyelid is supported by the tarsal plate and the lateral/medial canthal tendons. Laxity in these structures allows the eyelid to rotate inward, bringing the lashes into direct contact with the corneal epithelium.
Pathophysiology
Involutional entropion results from the attenuation of the lower eyelid retractors and the overriding of the preseptal orbicularis muscle. This mechanical instability causes the eyelid margin to invert during blinking. Chronic irritation leads to a cycle of inflammation and further tissue contraction.
Clinical Manifestations
Patients present with foreign body sensation, tearing, and photophobia. The hallmark is trichiasis, where lashes abrade the cornea. Red flags include corneal ulceration, persistent pain, and decreased visual acuity, which indicate an ocular emergency.
Diagnosis
Diagnosis is established via slit-lamp examination to visualize lash-cornea contact. The snap-back test is the gold standard for assessing eyelid laxity; if the lid does not return to the globe within 1-2 seconds after pulling it away, laxity is confirmed.
Treatment
Initial management includes lubricating eye drops and ointments to protect the cornea. Taping the eyelid to the cheek provides temporary relief. Surgical correction (e.g., lateral tarsal strip) is the definitive treatment. Avoid delaying surgery if there is evidence of corneal epithelial defects.
Prognosis
Prognosis is excellent with surgical intervention. Failure to treat leads to corneal scarring, vascularization, and potential permanent vision loss. Patients require monitoring for recurrence of laxity.
Differential Diagnosis
Ectropion: outward turning of the eyelid margin
Trichiasis: isolated misdirected lashes without eyelid inversion
Distichiasis: second row of lashes growing from Meibomian glands
Blepharitis: inflammation of the eyelid margin without inversion
Corneal abrasion: traumatic defect without eyelid malposition