title: Usefulness of intraoperative monitoring of oculomotor and abducens nerves during surgical treatment of the cavernous sinus meningiomas.
abstract: OBJECTIVE
  We analyzed the usefulness and prognostic value of intraoperative monitoring for identification of the oculomotor (III) and the abducens (VI) nerve in patients with cavernous sinus meningiomas.
  
  
  METHODS
  43 patients diagnosed with cavernous sinus meningiomas were divided according to their topography. Function of the nerves was scored on original clinical and neurophysiological scales.
  
  
  RESULTS
  The percentage of nerves identified correctly with the monitoring was significantly higher (91% vs. 53% for nerve III and 70% vs. 23% for nerve VI, p<0.001). The fractions of nerves III and VI identified correctly by means of the monitoring were significantly higher in the case of tumors with intra- and extracavernous location (89% vs. 32%, p<0.01) and intracavernous tumors (80% vs. 20%, p<0.05), respectively. The quality of post-resection recording correlated with functional status of both the nerves determined 9 months after the surgery (R=0.51, p<0.001 for nerve III and R=0.57, p<0.01 for nerve VI). Even a trace or pathological response to the post-resection stimulation was associated with improved functional status (90% vs. 50%, p<0.05 for nerve III and 93% vs. 38%, p<0.01 for nerve VI).
  
  
  CONCLUSIONS
  Neurophysiological monitoring of ocular motor nerves enables their intraoperative identification during resections of the cavernous sinus meningiomas. Intraoperative monitoring of nerve III is particularly important in the case of tumors with extra- and intracavernous location, and the monitoring of nerve VI in the case of intracavernous tumors. The outcome of the post-resection monitoring has prognostic value with regard to the clinical status of the nerves on long-term follow-up.
authors.affiliation: Department of Neurosurgery, Medical University of Silesia, Regional Hospital, Sosnowiec, Poland. Electronic address: wkaspera@wp.pl.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Kaspera
authors.affiliation: Department of Neurosurgery, Medical University of Silesia, Regional Hospital, Sosnowiec, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Adamczyk
authors.affiliation: Department of Laryngology, Medical University of Silesia, University Hospital, Katowice, Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Ślaska-Kaspera
authors.affiliation: Department of Neurosurgery, Medical University of Silesia, Regional Hospital, Sosnowiec, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Ładziński
mesh_terms: D000010:Abducens Nerve / Q000502:physiology*; D000328:Adult; D000368:Aged; D002426:Cavernous Sinus / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008577:Meningeal Neoplasms / Q000601:surgery*; D008579:Meningioma / Q000601:surgery*; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D009802:Oculomotor Nerve / Q000502:physiology*
keywords: Abducens nerve; Cavernous sinus meningiomas; Neurophysiological intraoperative monitoring; Oculomotor nerve