Cornea & external disease · practice question
[READINESS SEED] Months after a third nerve palsy, an adult's ptotic lid rises…
[READINESS SEED] Months after a third nerve palsy, an adult's ptotic lid rises whenever the eye moves down or adducts. What best explains the lid movement with gaze?
Show the answer and explanationAnswer and explanation
Answer: A. Aberrant oculomotor regrowth to the levator
After an oculomotor palsy, regenerating axons can be misdirected so that fibers meant for the medial or inferior rectus reach the levator; the lid then elevates on adduction or downgaze (pseudo-von Graefe sign). The post-palsy history and gaze-linked lid movement are the clues.
Clinical pearl: Aberrant regeneration after a spontaneous (non-traumatic) third nerve palsy is a red flag for a compressive aneurysm or tumor and warrants imaging.