Weber's Syndrome constitutes an ipsilateral third nerve paralysis with a contralateral hemiplegia. It is due to a lesion in one half of the midbrain e.g. as a result of occlusion of the paramedian branches of the basilar artery.
If there is a localised lesion in the region of the red nucleus, then there is paralysis of upward gaze.
Last reviewed 05/2018