title: [Preoperative etiological diagnosis of hemifacial spasm: a comparative study between magnetic resonance tomographic angiography and intra-operative findings].
abstract: OBJECTIVE
  To summarize retrospectively the value of magnetic resonance tomographic angiography (MRTA) in the preoperative etiological diagnosis for hemifacial spasms (HFS).
  
  
  METHODS
  336 cases of HFS, 127 male and 209 female, aged 46.2 (16-75), with a course of 1-29 years (6.2 years on average) and with the unilateral symptoms except one case were subjected to routine MRTA check up preoperatively. The MRTA findings were compared with the operative findings.
  
  
  RESULTS
  Pre-operative evaluation by MRTA discerned 273 offending vessels with a positive rate of 81.3%, which were completely consistent with the intra-operative findings. The false positive and false negative rates were 8.0% and 9.8% respectively. Three cases of HFS due to secondary cause were found: one of CPA meningioma at the cerebellopontine angle and two cases of cholesteatoma.
  
  
  CONCLUSIONS
  MRTA imaging provides more useful information concerning the etiology of hemifacial spasm than any other available diagnostic modalities. It is an effective and reliable means for pre-operative evaluation of the existence and sources of offending vessels in hemifacial spasm patients, and thus benefits the planning and guiding of intra-operative manipulation.
authors.affiliation: Department of Neurosurgery, Rui jin Hospital, Shanghai Second Medical University, Shanghai 200025, China.
authors.forename: Wei-guo
authors.initials: WG
authors.lastname: Zhao
authors.forename: Jun
authors.initials: J
authors.lastname: Zhu
authors.forename: Jian-kang
authors.initials: JK
authors.lastname: Shen
authors.forename: Jin-qing
authors.initials: JQ
authors.lastname: Hu
authors.forename: Ling
authors.initials: L
authors.lastname: Tan
authors.forename: Fei
authors.initials: F
authors.lastname: Miu
authors.forename: Ke-min
authors.initials: KM
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D019569:Hemifacial Spasm / Q000000981:diagnostic imaging* / Q000601:surgery; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D011859:Radiography