Which presentation is typical of lateral medullary (Wallenberg) syndrome?

Which presentation is typical of lateral medullary (Wallenberg) syndrome?

• A. Vertigo and nystagmus with ipsilateral facial numbness.
• B. Bilateral limb weakness with preserved cranial nerves.
• C. Hemiparesis with aphasia.
• D. Only ataxia without other symptoms.

Answer: (A)

Lateral medullary (Wallenberg) syndrome reflects a brainstem stroke from PICA occlusion, producing signs from the vestibular nuclei and the spinal trigeminal nucleus along with other nearby structures. Vertigo and nystagmus come from vestibular system involvement, while ipsilateral facial numbness arises from disruption of the spinal trigeminal nucleus, which carries facial sensation on the same side. This combination—vestibular symptoms with ipsilateral facial sensory loss—fits the lateral medullary pattern most directly, because it shows brainstem-level involvement without the cortical signs you’d expect from a major hemispheric stroke. Other presentations don’t align with this syndrome: bilateral limb weakness suggests widespread or bilateral tract involvement; hemiparesis with aphasia points to a cortical or MCA territory issue; and isolated ataxia without additional cranial nerve or sensory findings is more typical of a cerebellar lesion.

Lateral medullary (Wallenberg) syndrome reflects a brainstem stroke from PICA occlusion, producing signs from the vestibular nuclei and the spinal trigeminal nucleus along with other nearby structures. Vertigo and nystagmus come from vestibular system involvement, while ipsilateral facial numbness arises from disruption of the spinal trigeminal nucleus, which carries facial sensation on the same side. This combination—vestibular symptoms with ipsilateral facial sensory loss—fits the lateral medullary pattern most directly, because it shows brainstem-level involvement without the cortical signs you’d expect from a major hemispheric stroke.

Other presentations don’t align with this syndrome: bilateral limb weakness suggests widespread or bilateral tract involvement; hemiparesis with aphasia points to a cortical or MCA territory issue; and isolated ataxia without additional cranial nerve or sensory findings is more typical of a cerebellar lesion.