Weber's syndrome

Weber's syndrome
Weber's syndrome
Classification and external resources

Midbrain cross section showing lesion
ICD-10 G46.3
ICD-9 344.89
DiseasesDB 31247
MeSH D020526

Weber's syndrome (superior alternating hemiplegia) is a form of stroke characterized by the presence of an oculomotor nerve palsy and contralateral hemiparesis or hemiplegia.


Cause and presentation

This lesion is usually unilateral and affects several structures in the midbrain including:

Structure damaged Effect
substantia nigra contralateral parkinsonism because its dopaminergic projections to the basal ganglia innervate the ipsilateral hemisphere motor field, leading to a movement disorder of the contralateral body.
corticospinal fibers contralateral hemiparesis and typical upper motor neuron findings
corticobulbar tract difficulty with contralateral lower facial muscles and hypoglossal nerve functions
oculomotor nerve fibers ipsilateral oculomotor nerve palsy with a drooping eyelid and fixed wide pupil pointed down and out. This leads to diplopia
Human brainstem blood supply description. Posterior cerebral artery is #6, and midbrain is behind it.

It is caused by midbrain infarction as a result of occlusion of the paramedian branches of the posterior cerebral artery or of basilar bifurcation perforating arteries.[1]


It carries the name of Sir Herman David Weber, a German-born physician working in London, who described the condition in 1863.[2][3] It is unrelated to Sturge-Weber syndrome or Klippel-Trenaunay-Weber syndrome.


  1. ^ -932511721 at GPnotebook
  2. ^ Weber HD (1863). "A contribution to the pathology of the crura cerebri". Medico-Chirurgical Transactions 46: 121–139. 
  3. ^ synd/407 at Who Named It?

External links

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