title: Electromyographically Guided Nerve Combing Makes Microvascular Decompression More Successful in Hemifacial Spasm with Persistent Abnormal Muscle Response.
abstract: BACKGROUND
  Microvascular decompression (MVD) of the facial nerve monitored intraoperatively by abnormal muscle response (AMR) activity is a common treatment for hemifacial spasm. AMR frequently persists after MVD, however, for which electromyography (EMG)-guided nerve combing sometimes is recommended. Because no research regarding the success of EMG-guided nerve combing has been published, we compared the effectiveness of nerve combing after MVD with simple MVD in cases including persistent AMR.
  
  
  METHODS
  A retrospective study of 127 cases of hemifacial spasm treated with persistent AMR after MVD treatment occurring between January 2011 and June 2015 was conducted. Among the 127 total cases, EMG-guided nerve combing was used in 72 patients and simple MVD in 55 patients.
  
  
  RESULTS
  For simple MVD, success rates at 1 day, 7 days, 1 month, 3 months, and 1 year after surgery were all approximately 80%; the success rates of MVD with nerve combing were significantly greater (P < 0.05) than those of simple MVD, by 15.83%, 15.4%, 17.22%, 17.65%, and 17.65%, respectively. The incidence rates of facial palsy in simple MVD were 12.73%, 14.55%, 10.91%, 3.64%, and 1.82%, respectively; those in the nerve combing group were 27.78% (P < 0.05 vs. simple MVD), 33.33% (P < 0.05), 25.00% (P = 0.05), 5.55% (P > 0.05), and 2.78% (P > 0.05), respectively.
  
  
  CONCLUSIONS
  In cases of hemifacial spasm with persistent AMR after MVD, EMG-guided nerve combing significantly improved the success rate of the operation. Although it also significantly increased the incidence of postoperative facial palsy over the short term (up to 1 week), incidences in the long term were not significantly different.
authors.affiliation: Department of Neurosurgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Center for diagnosis and treatment of cranial nerve diseases, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Neurosurgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Center for diagnosis and treatment of cranial nerve diseases, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Department of Neurosurgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Center for diagnosis and treatment of cranial nerve diseases, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Zhu
authors.affiliation: Department of Neurosurgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Center for diagnosis and treatment of cranial nerve diseases, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Yin-Da
authors.initials: YD
authors.lastname: Tang
authors.affiliation: Department of Neurosurgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Center for diagnosis and treatment of cranial nerve diseases, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Ying
authors.affiliation: Department of Neurosurgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Center for diagnosis and treatment of cranial nerve diseases, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: Department of Neurosurgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Center for diagnosis and treatment of cranial nerve diseases, Shanghai Jiao Tong University, Shanghai, China. Electronic address: xinhuaneuro@126.com.
authors.forename: Shi-Ting
authors.initials: ST
authors.lastname: Li
mesh_terms: D004558:Electric Stimulation; D004576:Electromyography; D005152:Facial Muscles / Q000503:physiopathology*; D005154:Facial Nerve / Q000502:physiology; D005158:Facial Paralysis / Q000453:epidemiology / Q000209:etiology / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D019569:Hemifacial Spasm / Q000601:surgery*; D006801:Humans; D008297:Male; D061145:Microvascular Decompression Surgery / Q000379:methods*; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology; D012189:Retrospective Studies; D016896:Treatment Outcome
keywords: AMR; Abnormal muscle response; HFS; Hemifacial spasm; MVD