Wallenberg's syndrome

Today we discussed stroke in general, central vs. peripheral vertigo, and specifically the lateral medullary syndrome (i.e. Wallenberg's)

Vertigo- Central (brainstem, cerebellum) vs. Peripheral (inner ear)

Central:

Nystagmus is often bidirectional, sometimes vertical

Visual fixation makes no difference in symptoms

Vertigo may be chronic and often not severe

Cranial nerve deficits are common

Ear symptoms are absent

Peripheral:
Nystagmus is horizontal, often unidirectional

Visual fixation may improve symptoms

Vertigo is often severe

Head position often clearly exacerbates

No associated cranial nerve deficits

Often assoicated ear symptoms (deafness, tinnitus, otalgia)

Differential diagnosis of stroke -i.e. acute onset focal neurological deficit(s)
Seizure, dissection (esp young pt), migraine, demyelination, vasculitis. Any underlying brain abnormality with something that can cause delirium can cause focal findings (inc. infection, metabolic disturbances)

Lateral medullary stroke:
Results from occlusion of the ipsilateral vertebral artery (thrombotic, embolic, dissection), or a branch, the posterior inferior cerebellar artery.

Possible findings ipsilateral to lesion:
Pain, numbness of half of face (V1-V3)- 5th nerve nucleus
Ataxia, falling towards side of lesion- spinocerebellar tract, cerebellar peduncle
Nystagmus, diplopia, vertigo, nausea and vomiting- ipsilateral vestibular (8th nerve) nucleus
Horner's syndrome- ptosis, miosis, anhydrosis- sympathetic chain
Dysphagia, hoarseness- 9th and 10th nerve nuclei
Facial weakness (usually lower motor neuron type if 7th nerve nucleus involved)

Possible findings contralateral to lesion
Impaired sensation over half of body- spinothalamic tract
Limb power usually not involved because is more medial medullary (pyramidal tract)

Others: Intractable hiccups

Link:

Click here for a NEJM review of vertebrobasilar disease that includes a discussion of the lateral medullary syndrome