Entropion & Ectropion

Overview

Entropion and ectropion are opposite disorders of eyelid position: entropion is inward rotation of the eyelid margin (causing lashes and skin to contact the globe), while ectropion is outward rotation of the eyelid margin away from the globe. Both most commonly affect the lower eyelid and result from an imbalance of the external and internal anatomic forces that normally hold the eyelid margin in its correct apposition against the globe.¹

Epidemiology & Risk Factors

The most common form of both conditions is involutional (age-related), resulting from generalized eyelid laxity that develops with aging — horizontal lid laxity, canthal tendon laxity, and attenuation of the lower lid retractors all contribute. Other causes include cicatricial changes (from prior trauma, surgery, chronic inflammation, or skin conditions pulling the lid margin out of position, typically producing ectropion), paralytic ectropion (from facial nerve palsy impairing orbicularis oculi tone), spastic entropion (from orbicularis muscle overriding the tarsal margin, often related to longstanding ocular irritation or postoperative changes), and congenital forms (rare, presenting in infancy).

Pathophysiology

Involutional entropion results from a combination of horizontal lid laxity, disinsertion or attenuation of the lower lid retractors, and overriding of the preseptal orbicularis muscle over the pretarsal orbicularis, allowing the lid margin to rotate inward. Involutional ectropion results primarily from horizontal lid laxity (canthal tendon laxity) combined with gravitational effects on lid tissue, allowing the margin to fall away from the globe. In both conditions, the imbalance of forces acting on the lower eyelid disrupts the normal protective lid-globe relationship, exposing the ocular surface to either mechanical trauma from misdirected lashes (entropion) or inadequate coverage and tear film distribution (ectropion).¹

Clinical Presentation

Both conditions cause ocular irritation and loss of proper eye protection, presenting with symptoms such as foreign body sensation, tearing, redness, and discomfort.¹ Entropion classically causes a sensation of a foreign body or lash rubbing against the eye (trichiasis-like irritation from the inward-turned lashes), while ectropion classically causes epiphora (tearing, from malposition of the punctum away from the tear lake) and exposure-related dryness or irritation.

Exam Findings

• Entropion: visible inward rotation of the lid margin, with lashes contacting the cornea/conjunctiva, best appreciated on downgaze or with gentle manual eyelid manipulation testing for laxity
• Ectropion: visible outward rotation of the lid margin away from the globe, with the palpebral conjunctiva exposed and the punctum often everted away from the tear lake
• Positive snap-back test or lower lid distraction test, both used to assess and quantify the degree of horizontal lid laxity underlying involutional ectropion (and, similarly, informing entropion assessment)²
• Signs of ocular surface compromise in more advanced or longstanding cases: conjunctival injection, punctate keratopathy, or corneal abrasion from either misdirected lashes (entropion) or exposure (ectropion)

Differential Diagnosis

• Trichiasis without frank entropion (misdirected lashes from a structurally normal lid position, distinguished by normal lid margin position on exam)
• Floppy eyelid syndrome (excessive lid laxity allowing spontaneous eversion, often associated with obstructive sleep apnea, distinguished by a distinct pattern of lid rubbery/laxity and eversion)
• Blepharospasm or other causes of lid margin irritation without a true anatomic malposition
• Cicatricial versus involutional etiology, an important distinction since cicatricial cases (from trauma, chronic inflammation, or skin conditions) typically require addressing the underlying scarring process in addition to (or instead of) standard involutional-type repair

Management

Diagnosis is clinical, based on inspection of lid position (including on downgaze and with digital manipulation) and formal assessment of horizontal lid laxity via the snap-back test and lower lid distraction test.² Untreated entropion or ectropion can lead to recurrent inflammation of the conjunctiva and cornea, conjunctival neovascularization, corneal abrasion or perforation, and, in severe or longstanding cases, vision loss, making timely surgical referral important once conservative measures (lubrication, taping) prove inadequate.¹

Surgical repair is the definitive treatment for both conditions. A study evaluating outcomes of lower eyelid entropion and ectropion repair (including a modified Wheeler's method for entropion correction) found statistically significant improvement in patient-reported symptoms and validated grading scales after surgery, with very good functional and esthetic results in 70% of the overall cohort and in over 80% of patients specifically treated with the modified Wheeler's method; recurrence occurred in a minority of cases (12% in a prospective cohort, 18% in a retrospective cohort), with only minor complications, and quality of life improved significantly across somatic, psychological, and environmental domains.¹

For involutional ectropion specifically, the lateral tarsal strip procedure — which addresses horizontal lid laxity by shortening and reattaching the lateral canthal tendon — achieved a 95% success rate in a retrospective analysis of 85 eyelids, with 86% of eyelids achieving an excellent postoperative lid position; only four eyelids required a second surgical intervention, and mild, generally self-limited complications (epiphora, mild pain, wound hemorrhage, edema) were common but resolved within about a week in the large majority of cases without further treatment.² Notably, this study found no significant correlation between preoperative ectropion severity and the degree of surgical improvement, suggesting the procedure is broadly effective across a range of severity.²

Complications

• Corneal abrasion, ulceration, or, in severe untreated entropion, corneal perforation from chronic mechanical trauma
• Conjunctival neovascularization and chronic conjunctival inflammation from longstanding lid malposition¹
• Epiphora and exposure keratopathy from untreated ectropion
• Recurrence after surgical repair, occurring in a meaningful minority of cases even with appropriate technique¹
• Minor postoperative complications (epiphora, wound hemorrhage, edema), generally self-limited and resolving within about a week after lateral tarsal strip surgery²

Clinical Pearls

• Both entropion and ectropion are most commonly involutional (age-related), driven primarily by horizontal eyelid laxity
• The snap-back test and lower lid distraction test are simple, essential bedside tools for quantifying horizontal lid laxity and supporting the diagnosis²
• Surgical repair produces significant, durable symptom relief and quality-of-life improvement, with generally low complication rates and a meaningful but manageable recurrence risk¹
• The lateral tarsal strip procedure is a highly effective, reproducible technique for involutional ectropion, achieving excellent outcomes regardless of preoperative severity²
• Distinguishing cicatricial from purely involutional etiology is essential, since cicatricial cases require addressing the underlying scarring process for durable correction

Common Pitfalls

• Attributing chronic tearing or irritation to "dry eye" without examining lid position and performing laxity testing
• Delaying surgical referral until significant corneal complications (abrasion, ulceration) have already developed
• Failing to distinguish cicatricial from involutional etiology, leading to inadequate surgical planning
• Underestimating the value of a thorough preoperative laxity assessment (snap-back test, distraction test) in surgical planning
• Assuming surgical outcomes will be poor in more severe ectropion cases, when evidence suggests the lateral tarsal strip procedure performs consistently well across severity levels²