title: Hemifacial spasm and arterial hypertension.
abstract: BACKGROUND
  Hemifacial spasm (HFS) is a form of segmental myoclonus often associated with vascular compression of the seventh nerve at its exit in the brain stem. Although a few uncontrolled studies describe the association of arterial hypertension (AH) with HFS, their relationship remains to be elucidated.
  
  
  OBJECTIVE
  To compare the clinical and radiologic features of patients with HFS and subjects with blepharospasm (BLS) with special emphasis on the presence of AH.
  
  
  METHODS
  Chart review of all patients with HFS and BLS seen at a hospital-based movement disorders clinic from July 1993 through March 1998, analyzing the following parameters: gender, age at onset, frequency of AH, and abnormalities on computerized tomography (CT) or magnetic resonance imaging (MRI) studies. Neuroimaging studies (52 CT and 14 MRI) were performed in 45 subjects with HFS and in 21 with BFS. All patients were examined by one of the authors (FC).
  
  
  RESULTS
  HFS and BLS were diagnosed in 48 (31 women, 17 men) and 34 (28 women, 6 men) patients, respectively. The age at onset was 50.1 +/- 12.6 years in HFS and 50.3 +/- 16.5 years in BLS. AH was diagnosed in 32 (66.7%) subjects with HFS and in 13 (38.2%) patients with BLS (chi-square p = 0.01). Neuroimaging evidence of vascular tortuosity in the cerebello-pontine angle was identified in 16 (25.4%) patients, all of whom had HFS (38.1%). Thirteen of 37 patients with AH who had imaging studies displayed vascular tortuosity in the cerebello-pontine angle (chi-square p = 0.01).
  
  
  CONCLUSIONS
  AH is significantly more common in HFS than in BLS. AH is related to vascular tortuosity in the cerebello-pontine angle. Our findings suggest that AH may be an important risk factor for HFS.
authors.affiliation: Movement Disorders Clinic, Department of Neurology, The Federal University of Minas Gerais, Belo Horizonte, Brazil.
authors.forename: L D
authors.initials: LD
authors.lastname: Oliveira
authors.forename: F
authors.initials: F
authors.lastname: Cardoso
authors.forename: A P
authors.initials: AP
authors.lastname: Vargas
mesh_terms: D001764:Blepharospasm / Q000175:diagnosis; D002530:Cerebellopontine Angle / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D019569:Hemifacial Spasm / Q000175:diagnosis* / Q000209:etiology*; D006801:Humans; D006973:Hypertension / Q000150:complications* / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed