lagophthalmos

Lagophthalmos is the inability to fully close the eyelids, leaving part of the ocular surface exposed. It may occur only during sleep (nocturnal lagophthalmos) or persist during waking hours, and can lead to exposure keratopathy if the cornea is not adequately protected.

Common causes include facial nerve (VII) palsy such as Bell's palsy or Ramsay Hunt syndrome, eyelid scarring from burns or prior surgery, mechanical lid malpositions such as ectropion or entropion, thyroid-associated orbitopathy with proptosis, trauma, neuromuscular disorders, and congenital eyelid anomalies or complications after oculoplastic procedures.

Symptoms and signs consist of dry eyes, grittiness, tearing, burning, photophobia, and recurrent redness. On examination the eye may show reduced blinking and exposure-related surface changes such as corneal or conjunctival staining if keratopathy is present. Diagnosis is clinical, supported by assessment of lid closure and corneal integrity; imaging or neurologic evaluation is performed if an underlying neurologic cause is suspected.

Management focuses on protecting the ocular surface and restoring lid closure. Conservative measures include frequent lubrication with artificial tears, ocular lubricating ointments at night, eyelid taping or moisture shields, and specialized devices such as eyelid weights to help closure. Temporary tarsorrhaphy or botulinum toxin-induced ptosis may be used, and permanent tarsorrhaphy or lid surgery may be indicated for persistent cases or when the underlying cause requires surgical correction.

Prognosis varies with etiology; some cases improve with recovery of function, while chronic lagophthalmos can lead to corneal ulcers, scarring, and vision-threatening complications if not managed.