title: [Causes of ineffectiveness of microvascular decompression for hemifacial spasm].
abstract: OBJECTIVE
  To study causes of ineffectiveness of microvascular decompression (MVD) in treatment of hemifacial spasm (HFS).
  
  
  METHODS
  Reoperative MVD was performed in 23 HFS patients with previous ineffective MVD. In the patients, the main causes of ineffectiveness included misjudgment of compressing vessels (7 patients), improper insertion of decompressing grafts (9), improper selection of grafts (5) and small grafts (2).
  
  
  RESULTS
  Symptoms of HFS disappeared immediately after the second MVD in 21 patients and delayed in 2 patients (after 2 weeks, 6 weeks). No recurrence of HFS was noted during the follow-up period of 1.0 - 6.0 years (mean 3.4 years).
  
  
  CONCLUSIONS
  MVD is an effective microsurgical method for treating HFS. Accurate judgement of compressing vessels and proper decompression are the key to surgical effectiveness.
authors.affiliation: Department of Neurosurgery, China-Japan Friendship Hospital, Ministry of Health, Beijing 100029, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Yuan
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Si-xun
authors.initials: SX
authors.lastname: Zhang
authors.forename: Yan-bing
authors.initials: YB
authors.lastname: Yu
authors.forename: Guo-qiang
authors.initials: GQ
authors.lastname: Chen
authors.forename: Kui-ming
authors.initials: KM
authors.lastname: Zhao
authors.forename: Jing
authors.initials: J
authors.lastname: Guo
authors.forename: Huan-cong
authors.initials: HC
authors.lastname: Zuo
mesh_terms: D000328:Adult; D019299:Decompression, Surgical / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D019569:Hemifacial Spasm / Q000601:surgery*; D006801:Humans; D008297:Male; D018447:Medical Futility; D008866:Microsurgery / Q000379:methods; D008875:Middle Aged; D012086:Reoperation; D016896:Treatment Outcome; D014656:Vascular Surgical Procedures / Q000379:methods*; D055815:Young Adult