A 58-year-old man develops sudden-onset ipsilateral facial analgesia with contralateral limb analgesia, ipsilateral Horner syndrome, dysphagia, and hoarseness. The lesion responsible is in the:

• A Medial medulla (anterior spinal artery territory)
• B Dorsal pons at the level of CN VI nucleus
• C Lateral medulla (posterior inferior cerebellar artery territory) ✓
• D Lateral midbrain involving the cerebral peduncle

Explanation

The constellation of ipsilateral facial analgesia (descending trigeminal nucleus/tract), contralateral limb analgesia (spinothalamic tract), ipsilateral Horner (descending sympathetic fibers), dysphagia, and hoarseness (CN IX/X nuclei or fascicles) constitutes Wallenberg syndrome from PICA territory infarction in the lateral medulla. Medial medullary infarction (Dejerine) causes ipsilateral tongue deviation, contralateral hemiplegia, and contralateral dorsal-column loss — without Horner or CN IX/X involvement. Pontine and midbrain lesions produce different cranial nerve signs.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.