title: Comorbid intracranial vertebral artery asymmetry as a risk factor for severe vestibular neuronitis.
abstract: BACKGROUND
  Our previous study had demonstrated that verterbral artery hypoplasia (VAH) contribute to ipsilateral vestibular dysfunction. The aim of this study was to test if VAH contributes to prognosis of vestibular neuronitis (VN) through presumed regional malperfusion.
  
  
  METHODS
  We performed a prospective magnetic resonance angiographic registry in patients with acute vestibular neuritis in which were then assigned to VAH (n=29) and control group (n=40). Vestibular function was determined by caloric irrigation, with the use of the vestibular paresis formula (to measure the extent of unilateral caloric paresis) within 3 days after the onset of symptoms and 12 months afterward.
  
  
  RESULTS
  The baseline vestibular paresis was higher (56.8 ± 15.9%) in the VAH VN subjects (n=29), than in VN subjects without VAH (n=40) (37.4 ± 17.7%) (p=0.01). Analysis of variance showed a less percentage of the VAH group return to normal at 4th and 12th week visit.
  
  
  CONCLUSIONS
  Our results suggested that comorbid VAH may predispose to severe VN at acute stage.
authors.affiliation: Department of Neurology, Far-Eastern Memorial Hospital, New Taipei City, Taiwan, Republic of China.
authors.forename: Yu-Ming
authors.initials: YM
authors.lastname: Chuang
authors.forename: Chang-Ming
authors.initials: CM
authors.lastname: Chern
authors.forename: Wen-Huei
authors.initials: WH
authors.lastname: Liao
authors.forename: Li-Chi
authors.initials: LC
authors.lastname: Hsu
authors.forename: Chiang-Feng
authors.initials: CF
authors.lastname: Lien
authors.forename: Jiing-Feng
authors.initials: JF
authors.lastname: Lirng
authors.forename: An-Suei
authors.initials: AS
authors.lastname: Shiao
authors.forename: James Shih-Chi
authors.initials: JS
authors.lastname: Ko
mesh_terms: D000328:Adult; D002150:Caloric Tests; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012307:Risk Factors; D014711:Vertebral Artery / Q000002:abnormalities* / Q000000981:diagnostic imaging; D014724:Vestibular Function Tests; D020338:Vestibular Neuronitis / Q000175:diagnosis* / Q000000981:diagnostic imaging