Which combination of findings best distinguishes simple congenital ptosis from aponeurotic and myogenic ptoses acquired later in life?

• A High lid crease with thinning of the lid on downgaze
• B Ptosis increasing on chewing with jaw movement
• C Normal levator function worsening through the day
• D Poor levator function with absence of the lid crease and lid lag on downgaze ✓

Explanation

Simple congenital ptosis results from dystrophic development of the levator muscle, which is replaced partly by fibrous tissue. Because fibrous tissue does not relax, the lid cannot fully depress either, producing lid lag on downgaze, and the levator function is poor with an absent or poorly formed lid crease. A high crease with lid thinning suggests aponeurotic dehiscence, diurnal variation suggests myasthenia, and ptosis linked to jaw movement defines Marcus Gunn jaw-winking synkinesis.

Reference: AAO Basic and Clinical Science Course, Orbit, Eyelids, and Lacrimal System, 2023-2024 ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.