A 64-year-old woman develops sudden onset of LEFT lower motor neuron tongue weakness, with the tongue deviating to the left on protrusion, RIGHT hemiplegia, and RIGHT loss of vibration and joint position sense. Pain and temperature are preserved. Which arterial territory is infarcted?

• A Posterior inferior cerebellar artery
• B Posterior cerebral artery
• C Anterior inferior cerebellar artery
• D Medial medullary branches of the anterior spinal artery ✓

Explanation

This is medial medullary (Dejerine) syndrome: ipsilateral hypoglossal palsy from involvement of emerging nerve fibres, contralateral hemiplegia from pyramid damage, and contralateral loss of vibration and proprioception from medial lemniscus damage. The paramedian medullary territory is supplied by branches of the anterior spinal artery arising from the vertebral artery. PICA infarction produces the lateral medullary syndrome with pain temperature loss and ataxia, and pain sensation is characteristically spared in the medial syndrome.

Reference: Snell's Clinical Neuroanatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.