Lidptosis

Lidptosis, commonly referred to as ptosis or blepharoptosis, is the drooping of the upper eyelid. It can involve one eye (unilateral) or both (bilateral) and may be present at birth or develop later in life. Ptosis results from dysfunction of the eyelid elevator muscles (primarily the levator palpebrae superioris and its aponeurosis) or from impaired nerve supply, muscle disease, mechanical weight, or eyelid elevation strategies.

Ptosis is typically classified as congenital or acquired. Congenital ptosis arises from developmental abnormalities of the levator muscle or its innervation and often presents with reduced eyelid lift and limited levator function. Acquired ptosis has several subtypes: aponeurotic (age-related detachment of the levator aponeurosis, common in older adults); neurogenic (due to oculomotor nerve palsy or Horner syndrome); myogenic (muscle diseases such as muscular dystrophy or myasthenia gravis); mechanical (lid heaviness from swelling or lesions); and traumatic or iatrogenic causes.

Assessment relies on objective measurements. Clinicians record the margin reflex distance 1 (MRD1), eyelid crease height, and levator function (degree of eyelid movement from downgaze to upgaze). The examination may include assessment for anisocoria, pupil involvement, and signs of neuromuscular or autonomic disease. Laboratory tests, imaging, and specific tests (eg, ice test or edrophonium test for myasthenia gravis) may be used to identify underlying causes.

Treatment is tailored to cause and functional impact. Asymptomatic ptosis without visual compromise may be observed. Congenital ptosis with poor vision risk often requires surgical correction, typically levator resection/advancement or frontalis suspension. Acquired ptosis treatment targets the underlying condition and may involve similar eyelid surgery if visual field loss persists. Outcomes depend on etiology, levator function, and patient-specific factors.

Epidemiology varies by cause; age-related aponeurotic ptosis is common in older adults, while congenital ptosis is relatively rare. See also blepharoptosis and eyelid disorders.