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Wallenberg syndrome

Last updated: March 25, 2021

Wallenberg syndrome is a neurological condition caused by a lateral medullary infarction, which results from occlusion of either the posterior inferior cerebellar artery (PICA) or the vertebral artery. For this reason, it is also referred to as lateral medulla syndrome or PICA syndrome. Symptoms include ipsilateral Horner syndrome, palate weakness, hemiataxia, and contralateral sensory disturbances. Management is supportive, and may include swallowing and speech therapy, as well as a feeding tube in some cases.

Overview ^[1]
Clinical features		Structure affected
Ipsilateral	Dysphagia ↓ Gag reflex Hoarseness, dysphonia	Nucleus ambiguus (motor neuron)
	Ataxia, dysmetria, dysdiadochokinesia	Inferior cerebellar peduncle
	Horner syndrome Uncontrollable hiccups	Sympathetic fibers
	Vertigo (with falling towards the same side of the lesion) → vomiting Nystagmus that changes direction with gaze change diplopia	Vestibular nuclei
	Facial pain ^[2] Loss of pain and temperature in the face	Trigeminal nucleus and tract (sensory)
Contralateral	Loss of pain and temperature in the trunk and limbs	Lateral spinothalamic tract (sensory)

See stroke
HINTS exam
Imaging
- Diffusion-weighted MRI (confirmatory test): Shows infarct in the inferior cerebellar area or lateral medulla
- See ischemic stroke for specific imaging findings and other modalities.

Wallenberg's Syndrome Information Page. https://www.ninds.nih.gov/Disorders/All-Disorders/Wallenbergs-Syndrome-Information-Page. . Accessed: March 30, 2017.
Sabine Fitzek, Ulf Baumgärtner, Jürgen Marx, Felix Joachimski, Hubertus Axer, Otto W. Witte, Clemens Fitzek. Chapter 15 Pain and itch in Wallenberg's syndrome: anatomical–functional correlations. Elsevier ; 2006 : p. 187-194
Diplopia in Wallenberg's syndrome. https://www.ncbi.nlm.nih.gov/pubmed/15199730. Updated: January 1, 2004. Accessed: March 30, 2017.