title: Reversed corrective saccades during head impulse test in acute cerebellar dysfunction.
abstract: Patients with cerebellar lesions may show horizontal (positive)- or downward (perverted)-corrective saccades during horizontal head impulse test (HIT). However, corrective saccades in the direction of head rotation (reversed corrective saccades) have not been reported during HIT. We present two patients who showed reversed corrective saccades during horizontal HIT as an initial sign of acute cerebellitis. In contrast to the corrective saccades mostly observed in peripheral vestibular paresis, this paradoxical response indicates abnormally increased vestibulo-ocular responses due to cerebellar disinhibition over the vestibulo-ocular reflex. This paradoxical response should be considered an additional bedside cerebellar sign.
authors.affiliation: Department of Neurology, Korea University College of Medicine, Korea University Ansan Hospital, Ansan, South Korea, a-yeong@hanmail.net.
authors.forename: Jeong-Yoon
authors.initials: JY
authors.lastname: Choi
authors.forename: Ji-Soo
authors.initials: JS
authors.lastname: Kim
authors.forename: Jin-Man
authors.initials: JM
authors.lastname: Jung
authors.forename: Do-Young
authors.initials: DY
authors.lastname: Kwon
authors.forename: Moon Ho
authors.initials: MH
authors.lastname: Park
authors.forename: Chulhan
authors.initials: C
authors.lastname: Kim
authors.forename: June
authors.initials: J
authors.lastname: Choi
mesh_terms: D000328:Adult; D002150:Caloric Tests; D002526:Cerebellar Diseases / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology*; D002531:Cerebellum / Q000473:pathology; D004660:Encephalitis / Q000175:diagnosis / Q000503:physiopathology; D005260:Female; D064087:Head Impulse Test; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D012027:Reflex, Vestibulo-Ocular; D012438:Saccades; D014717:Vertigo / Q000175:diagnosis / Q000503:physiopathology