The value of intraoperative facial nerve electromyography in predicting facial nerve function after vestibular schwannoma surgery

Michael E. Sughrue, Rajwant Kaur, Ari J. Kane, Martin J. Rutkowski, Gurvinder Kaur, Isaac Yang, Lawrence H. Pitts, Andrew T. Parsa

Research output: Contribution to journalArticle

21 Scopus citations


The prognostic significance of intraoperative facial nerve electromyography (EMG) changes is not well-established in vestibular schwannoma (VS) surgery. We studied facial nerve EMG with a threshold >0.05 mA and performed subgroup analyses based on tumor size, resection approach, and extent of resection, for prediction of long-term facial nerve outcome. A total of 477 surgically treated VS patients were included. Elevated stimulation threshold exceeding >0.05 mA is a highly specific (90%), but very insensitive (29%) finding in this cohort. The positive predictive value and negative predictive values (NPV) of facial nerve EMG for detection of permanent facial palsy are 68% and 63%, respectively. The NPV decreased with increasing tumor size (72% versus [vs.] 64% vs. 53%) due to the increasing prevalence of post-operative facial nerve palsy in these patients. In conclusion, while facial nerve EMG is a critical adjunct for locating the facial nerve intraoperatively, its predictive value for facial nerve function remains to be determined.

Original languageEnglish (US)
Pages (from-to)849-852
Number of pages4
JournalJournal of Clinical Neuroscience
Issue number7
Publication statusPublished - Jul 1 2010
Externally publishedYes



  • Acoustic neuroma
  • Electromyography
  • Facial nerve
  • Microsurgery
  • Neuromonitoring
  • Vestibular schwannoma

ASJC Scopus subject areas

  • Surgery
  • Neurology
  • Clinical Neurology
  • Physiology (medical)

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