What are the signs and symptoms of lateral medullary (Wallenberg) syndrome in vertebrobasilar stroke?

Updated: Aug 09, 2021
  • Author: Vladimir Kaye, MD; Chief Editor: Stephen Kishner, MD, MHA  more...
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This syndrome is most often due to vertebral artery occlusion or, less commonly, to posterior inferior cerebellar artery (PICA) occlusion. Patients present with nausea, vomiting, and vertigo from involvement of the vestibular system.

Ipsilateral clinical features include the following:

  • Ataxia and dysmetria, due to damage to the inferior cerebellar peduncle and cerebellum

  • Horner syndrome (eg, ptosis, miosis, hypohidrosis or anhidrosis, enophthalmos), due to damage to descending sympathetic fibers

  • Facial pain and temperature loss

  • Reduced corneal reflex, from damage to the descending spinal tract and nucleus of CN V

  • Nystagmus

  • Hypoacusis (cochlear nucleus)

  • Dysarthria

  • Dysphagia

  • Paralysis of the pharynx, palate, and vocal cord

  • Loss of taste from the posterior third of the tongue (nuclei or fibers of CN IX and X)

Contralateral findings include the loss of pain and temperature sense in the body and extremities, indicating involvement of the lateral spinothalamic tract. Other findings include tachycardia and dyspnea (dorsal nucleus of CN X) and palatal myoclonus, a rhythmic involuntary jerking movement of the soft palate, pharyngeal muscles, and diaphragm. Palatal myoclonus sometimes follows infarction of the dentate nucleus of the cerebellum and inferior oliva.

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