Weber's syndrome

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:

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.

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