Weber's syndrome occurs due to lesions in the

Weber's syndrome (superior alternating hemiplegia) is a form of stroke characterized by the presence of an ipsilateral oculomotor nerve palsy and contralateral hemiparesis or hemiplegia. It is caused by midbrain infarction as a result of occlusion of the paramedian branches of the posterior cerebral aery or of basilar bifurcation perforating aeries. Ref: guyton and hall textbook of medical physiology 12 edition page number: 761,762763