Weber syndrome (weber-dubler syndrome; cerebellar peduncle syndrome; alternating oculomotor paralysis; ventral medial midbrain syndrome) 1

General: Lesion of the peduncle (crus), pons, or medulla, which interrupts the third nerve before it emerges from the peduncle and interrupts fibers in the pyramidal tract above the level of the third nuclei; hemorrhage and thrombosis; tumor of the pituitary region, extending posteriorly; also may result secondary to cerebrovascular disease.

Ocular: Ptosis; homolateral third nerve palsy (usually complete); fixed, dilated pupil.

Clinical: Contralateral hemiplegia; contralateral paralysis of face and tongue (supranuclear type).

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