title: New methodology for facial nerve monitoring in extracranial surgeries of vascular malformations.
abstract: OBJECTIVE
  To develop a more reliable methodology for monitoring the facial nerve in surgeries of vascular malformations where the extracranial segment of the nerve is at risk.
  
  
  METHODS
  Our methodology comprises: (1) preoperative mapping to identify the anatomical location of the nerve branches, (2) continuous intraoperative monitoring of the compound muscle action potential (CMAP) by stimulating the facial nerve extracranially, in close proximity to where the trunk of the facial nerve exits the skull at the stylomastoid foramen, (3) intraoperative mapping to identify the nerve branches during surgical dissection and quantify the innervating contribution of each branch to the target muscle.
  
  
  RESULTS
  Only three out of 201 surgeries (1.5%) had complete facial nerve trunk injury as a consequence of facial vascular malformation surgery.
  
  
  CONCLUSIONS
  We developed a new method to continuously stimulate the facial nerve extracranially eliciting an objective parameter--the CMAP amplitude--to constantly measure changes in the muscle responses throughout surgery, alerting the surgeon before the facial nerve is severely injured. Our methodology notably reduces the complete facial nerve injury during extracranial surgery of facial vascular malformations.
  
  
  CONCLUSIONS
  This comprehensive methodology may also be a valuable tool to prevent facial nerve injury during other types of extracranial surgeries where radical excisions are required.
authors.affiliation: Department of Intraoperative Neurophysiology, St Luke's Roosevelt Hospital, Mount Sinai Health System, New York, NY, USA. Electronic address: sulkatan@chpnet.org.
authors.forename: Sedat
authors.initials: S
authors.lastname: Ulkatan
authors.affiliation: Vascular Birthmark Institute of New York, St Luke's Roosevelt Hospital, Mount Sinai Health System, New York, NY, USA.
authors.forename: Milton
authors.initials: M
authors.lastname: Waner
authors.affiliation: Department of Intraoperative Neurophysiology, St Luke's Roosevelt Hospital, Mount Sinai Health System, New York, NY, USA.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Arranz-Arranz
authors.affiliation: Vascular Birthmark Institute of New York, St Luke's Roosevelt Hospital, Mount Sinai Health System, New York, NY, USA.
authors.forename: Inanna
authors.initials: I
authors.lastname: Weiss
authors.affiliation: Vascular Birthmark Institute of New York, St Luke's Roosevelt Hospital, Mount Sinai Health System, New York, NY, USA.
authors.forename: Theresa M J
authors.initials: TMJ
authors.lastname: O
authors.affiliation: Vascular Birthmark Institute of New York, St Luke's Roosevelt Hospital, Mount Sinai Health System, New York, NY, USA.
authors.forename: Mehra
authors.initials: M
authors.lastname: Saral
authors.affiliation: Department of Intraoperative Neurophysiology, St Luke's Roosevelt Hospital, Mount Sinai Health System, New York, NY, USA.
authors.forename: Vedran
authors.initials: V
authors.lastname: Deletis
authors.affiliation: Vascular Birthmark Institute of New York, St Luke's Roosevelt Hospital, Mount Sinai Health System, New York, NY, USA; Department of Interventional Neuroradiology at the Institute for Neurology and Neurosurgery, St Luke's Roosevelt Hospital, Mount Sinai Health System, New York, NY, USA.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Berenstein
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D020785:Central Nervous System Vascular Malformations / Q000601:surgery*; D005145:Face; D005154:Facial Nerve / Q000502:physiology* / Q000601:surgery; D006801:Humans; D016343:Monitoring, Intraoperative / Q000379:methods*; D012189:Retrospective Studies
keywords: Facial nerve; Intraoperative monitoring; Mapping; Surgery; Vascular malformation