title: [Intraoperative monitoring of the facial nerve : Vestibular schwannoma surgery].
abstract: BACKGROUND
  In vestibular schwannoma surgery, facial nerve injury with consecutive functional impairment is one of the most important complications. Intraoperative monitoring of facial nerve function has been developed in order to avoid this complication.
  
  
  OBJECTIVE
  Which methods for intraoperative monitoring have been developed? Which methods are in use today and what can they achieve in modern vestibular schwannoma surgery?
  
  
  METHODS
  This article provides an evaluation and summary of the literature, as well as a discussion of the methods and their ability to achieve the goals of intraoperative monitoring.
  
  
  RESULTS
  Intraoperative functional monitoring aims to identify and map the facial nerve in the surgical field during surgery. It also aims to identify potentially damaging events and allow for intraoperative prognosis of functional outcome. Available methods are direct electrical stimulation, free-running electromyogram (EMG), facial nerve evoked potentials, and processed EMG.
  
  
  CONCLUSIONS
  Identification and mapping of the facial nerve in the surgical field can be reliably achieved by direct electrical stimulation; potentially dangerous events can be identified in real time by the free-running EMG and the processed EMG, and almost in real time by facial nerve evoked potentials. Intraoperative prognostics are hampered by false-positive results with all available methods and have limited reliability.
authors.affiliation: Universitätsklinik und Poliklinik für Neurochirurgie, Universitätsklinikum Halle (Saale), Ernst-Grube-Str. 40, 06120, Halle (Saale), Deutschland. julian.prell@uk-halle.de.
authors.forename: J
authors.initials: J
authors.lastname: Prell
authors.affiliation: Universitätsklinik und Poliklinik für Neurochirurgie, Universitätsklinikum Halle (Saale), Ernst-Grube-Str. 40, 06120, Halle (Saale), Deutschland.
authors.forename: C
authors.initials: C
authors.lastname: Strauss
authors.affiliation: Universitätsklinik und Poliklinik für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie, Universitätsklinikum Halle (Saale), Halle (Saale), Deutschland.
authors.forename: S K
authors.initials: SK
authors.lastname: Plontke
authors.affiliation: Universitätsklinik und Poliklinik für Neurochirurgie, Universitätsklinikum Halle (Saale), Ernst-Grube-Str. 40, 06120, Halle (Saale), Deutschland.
authors.forename: S
authors.initials: S
authors.lastname: Rampp
mesh_terms: D019317:Evidence-Based Medicine; D020220:Facial Nerve Injuries / Q000175:diagnosis / Q000209:etiology* / Q000517:prevention & control*; D006801:Humans; D064795:Intraoperative Neurophysiological Monitoring / Q000009:adverse effects* / Q000379:methods*; D009464:Neuroma, Acoustic / Q000175:diagnosis* / Q000601:surgery*; D019635:Neurosurgical Procedures / Q000009:adverse effects / Q000379:methods*; D016896:Treatment Outcome
keywords: Acoustic neuroma; Cranial nerve VII; Electromyogram; Facial palsy; Intraoperative monitoring