Lateral Medullary Syndrome

Lateral Medullary Syndrome

The lateral medullary syndrome (or Wallenberg’s syndrome, after the neurologist who described it in 1895) results from damage (usually infarction) of the posterolateral medulla with or without involvement of the inferior cerebellum, producing the following clinical features:

  1. Nausea, vomiting, vertigo, oscillopsia (involvement of vestibular nuclei)
  2. Contralateral hypoalgesia, thermoanesthesia (spinothalamic tract)
  3. Ipsilateral facial hypoalgesia, thermoanesthesia, + facial pain (trigeminal spinal nucleus and tract)
  4. Horner’s syndrome (descending sympathetic tract), +/− ipsilateral

hypohidrosis of the body

  1. Ipsilateral ataxia of limbs (olivocerebellar/spinocerebellar fibers, inferior cerebellum)
  2. Dysphagia, dysphonia, impaired gag reflex

? +/− eye movement disorders, including nystagmus, abnormalities of ocular alignment (skew deviation, ocular tilt reaction, environmental tilt), smooth pursuit and gaze holding, and saccades (lateropulsion)
? +/− hiccups (singultus); loss of sneezing.

Infarction due to vertebral artery occlusion (occasionally posterior inferior cerebellar artery) or dissection is the most common cause of lateral medullary syndrome, although tumor, demyelination, and trauma are also recognized causes.



Fisher CM, Karnes W, Kubik C. Lateral medullary infarction: the pattern of vascular occlusion. Journal of Neuropathology andExperimental Neurology 1961; 20: 103-113
Pearce JMS. Wallenberg’s syndrome. In: Pearce JMS. Fragments ofneurological history. London: Imperial College Press, 2003: 233-236 Sacco RL, Freddo L, Bello JA, Odel JG, Onesti ST, Mohr JP. Wallenberg’s lateral medullary syndrome. Clinical-magnetic resonance imaging correlations. Archives of Neurology 1993; 50: 609-614


Cross References

Anesthesia; Dysphagia; Dysphonia; Environmental tilt; Gag reflex; Hemiataxia; Hiccup; Horner’s syndrome; Hypoalgesia; Hypohidrosis; Medial medullary syndrome; Nystagmus; Ocular tilt reaction; Oscillopsia; Saccades; Skew deviation; Sneezing; Vertigo