title: Upbeat nystagmus: clinicopathologic study of two patients.
abstract: Two patients had upward nystagmus on forward gaze before they died with acute caudal brainstem dysfunction. Bilateral dorsal paramedian damage in the rostral medulla, involving the perihypoglossal nuclei, was probably the critical lesion responsible for upbeat nystagmus.
mesh_terms: D000293:Adolescent; D000368:Aged; D002544:Cerebral Infarction / Q000473:pathology; D005260:Female; D006801:Humans; D008526:Medulla Oblongata / Q000098:blood supply / Q000473:pathology*; D009759:Nystagmus, Pathologic / Q000473:pathology*; D011149:Pons / Q000473:pathology