A 62-year-old man presents with sudden vertigo, hoarseness, and difficulty swallowing. Examination shows loss of pain and temperature sensation on the right side of the face and the left side of the trunk and limbs, right Horner syndrome, and ataxia on the right. Occlusion of which artery is the most likely cause?

• A Posterior inferior cerebellar artery ✓
• B Anterior inferior cerebellar artery
• C Superior cerebellar artery
• D Anterior spinal artery

Explanation

The findings are lateral medullary (Wallenberg) syndrome, caused by occlusion of the vertebral artery or its major branch, the posterior inferior cerebellar artery. The PICA supplies the lateral medulla, where the spinothalamic tract, spinal trigeminal nucleus, nucleus ambiguus, sympathetic fibers, and inferior cerebellar peduncle lie. The anterior inferior cerebellar artery occlusion produces lateral pontine syndrome with facial weakness and deafness, not nucleus ambiguus signs such as hoarseness.

Reference: Gray's Anatomy for Students, 4th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.