Brainstem syndromes

Arterial supply to the brainstem. Based on Wikipedia Brainstem figure. Edited under Creative Commons.

Lateral medullary (Wallenberg) syndrome

Famously attributed to PICA occlusion, but more commonly caused by vertebral artery atherothrombosis. Associated with significant and delayed cerebellar swelling resulting in cardiac arrest.

Sympathetic (desc. fibres)
CN V (desc. tract)
CN VIII
CN X (motor nucleus)
Spinothalamic tract
Spinocerebellar tract
Nucleus tractus solitarius
Horner's, ipsilateral
Pain, loss sensation face, ipsilateral
Vertigo, nystagmus, vomiting
Hoarse, dysphagia, palatal paralysis
Loss of pain/temp, contralateral
Ataxia, ipsilateral
Loss of taste

Medial medullary

Medial branches of vertebral artery occlusion infarcting the medial medullary pyramid, medial lemniscus, and hypoglossal fibres.

Pyramid
Medial lemniscus
CN XII
Paralysis UL & LL only, contralateral
Loss of position/vibration, contralateral
Paralysis of tongue, ipsilateral

Millard-Gubler (or Raymond-Foville)

Infarction of the base of the pons following occlusion of a branch of the basilar artery.

VII
VI
Corticospinal tract
Facial palsy, ipsilateral
Abducens palsy, ipsilateral
Hemiplegia, contralateral

Some consider the addition of a lateral conjugate palsy to the above to be “Foville’s syndrome”

Benedikt’s

Brainstem tegmentum infarct

  • CN III ipsilateral
  • Cerebellar contralateral

Weber

Base of midbrain infarct

  • CN III ipsilateral
  • Corticospinal tract