Entropion is the inward turning (inversion) of the eyelid, most commonly affecting the lower lid, though the upper lid may also be involved. This malposition causes eyelashes and lid margin to contact the cornea and conjunctiva, leading to irritation, tearing, and potential corneal injury.

• It can be involutional (age-related), cicatricial (scarring-related), spastic, or mechanical in origin.

• Causes include aging, chemical burns, mechanical injuries, orbicularis oculi spasm, ocular pemphigoid, Stevens-Johnson syndrome, and trachoma.

Pathophysiology

Entropion occurs when the structural or muscular support of the eyelid fails to maintain normal apposition:

• Involutional entropion (aging): Lid laxity, lower lid retractor disinsertion, and orbicularis muscle overriding lead to inward rotation.

• Cicatricial entropion: Scarring of the palpebral conjunctiva or tarsal plate pulls the eyelid inward.

• Spastic entropion: Reflex contraction of the orbicularis oculi causes temporary inward turning.

• Mechanical entropion: Tumors, edema, or other mass lesions push the lid inward.

Consequences include corneal abrasions, ulceration, chronic conjunctivitis, and potential visual impairment if untreated.

Examination Technique

Inspection

• Observe the eyelid in primary gaze for inward turning.

• Note eyelash-corneal contact, conjunctival irritation, or hyperemia.

Palpation

• Assess lid tone and laxity.

• Evaluate orbicularis muscle activity for spasm-related entropion.

Functional Assessment

• Test ocular surface for punctate epithelial erosions or corneal abrasion.

• Examine for scarring, cicatricial changes, or tumor as causative factors.

Clinical Features

Differential Diagnosis

Pediatric considerations

• Congenital entropion is rare, may cause corneal damage if untreated.

• Trachoma-induced entropion is a preventable cause in endemic regions.

Geriatric considerations

• Commonly involutional due to age-related tissue laxity and lower lid retractor weakness.

• Chronic eyelash-corneal contact can lead to corneal erosions and visual compromise.

Limitations

• Mild or intermittent entropion may be asymptomatic.

• Accurate differentiation from spastic or mechanical causes is necessary for appropriate management.

Patient Counseling

• Explain that entropion is a structural eyelid disorder that can cause chronic irritation and corneal damage.

• Highlight the importance of protecting the ocular surface, including lubricating drops or ointments.

• Discuss treatment options, including temporary measures (taping, bandage contact lenses) and surgical correction for persistent or symptomatic cases.

• Address underlying causes such as scarring, burns, or trachoma.

Conclusion

Entropion is an inward malposition of the eyelid that can compromise ocular health and vision if untreated. Early recognition, proper evaluation of the underlying cause, and timely management—often surgical—are essential to prevent chronic irritation, corneal injury, and vision loss.

References

1. Kersten RC, Kulwin DR. Eyelid Malpositions: Ectropion and Entropion. N Engl J Med. 2020;382:2298–2307.

2. American Academy of Ophthalmology. Basic and Clinical Science Course (BCSC): External Disease and Cornea. 2021–2022.

3. Jordan DR. Surgical correction of ectropion and entropion. Ophthalmology Clinics of North America. 2005;18(4):477–490.

4. Shields JA, Shields CL. Eyelid, Conjunctival, and Orbital Tumors. 4th ed. Philadelphia: Lippincott Williams & Wilkins; 2016.