title: Multimodal intraoperative monitoring during intramedullary spinal cord tumor surgery.
abstract: BACKGROUND
  The aim of this work is to evaluate the utility of multimodal intraoperative monitoring (IOM) during intramedullary spinal cord tumor (IMSCT) surgery in our institution, and to investigate which IOM events are likely to be encountered during critical surgical phases.
  
  
  METHODS
  Twenty-five patients who underwent IMSCT surgery with IOM were included in this study. Our multimodal IOM assessment included SSEP, mMEP, and fEMG monitoring. Positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity were assessed 24 h and 1 month after surgery. The IOM events during three main surgical phases were also investigated. For mMEP assessment, two warning criteria (>50 % decrease in mMEP amplitude and all-or-none mMEP amplitude presence) were employed.
  
  
  RESULTS
  Long-term outcome prediction was better when the all-or-none criterion was applied than when the >50 % amplitude decrease criterion was applied. Based on the all-or-none criterion, the PPV, NPV, sensitivity, and specificity were 60, 100, 100, and 91 %. Frequent IOM events were observed during the three major main surgical phases. Seven (29 %) patients showed SSEP events during opening of the spinal cord. During tumor removal, 21 of 25 patients (84 %) had IOM events, and 13 of 18 (72 %) of the fEMG events occurred prior to the mMEP events.
  
  
  CONCLUSIONS
  Based on the association of fEMG events with upcoming mMEP events during tumor removal, we recommend inclusion of fEMG monitoring in IOM. Multimodal IOM provides useful electrophysiological information during IMSCT surgery, especially during the main surgical phases.
authors.affiliation: Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Seung-Hyun
authors.initials: SH
authors.lastname: Jin
authors.affiliation: Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, Korea. chungc@snu.ac.kr.|Department of Neurosurgery, Seoul National University Hospital, Seoul, Korea. chungc@snu.ac.kr.|Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Korea. chungc@snu.ac.kr.
authors.forename: Chun Kee
authors.initials: CK
authors.lastname: Chung
authors.affiliation: Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, Korea.|Department of Neurosurgery, Seoul National University Hospital, Seoul, Korea.|Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Chi Heon
authors.initials: CH
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Seoul National University Hospital, Seoul, Korea.
authors.forename: Young Doo
authors.initials: YD
authors.lastname: Choi
authors.affiliation: Department of Neurosurgery, Seoul National University Hospital, Seoul, Korea.
authors.forename: Gilho
authors.initials: G
authors.lastname: Kwak
authors.affiliation: Department of Neurosurgery, Seoul National University Hospital, Seoul, Korea.
authors.forename: Bo Eun
authors.initials: BE
authors.lastname: Kim
mesh_terms: D000328:Adult; D001254:Astrocytoma / Q000601:surgery*; D004569:Electroencephalography / Q000379:methods; D004576:Electromyography / Q000379:methods; D004806:Ependymoma / Q000601:surgery*; D019054:Evoked Potentials, Motor; D005073:Evoked Potentials, Somatosensory; D005260:Female; D018325:Hemangioblastoma / Q000601:surgery; D006391:Hemangioma / Q000601:surgery*; D020786:Hemangioma, Cavernous, Central Nervous System / Q000601:surgery; D006801:Humans; D064795:Intraoperative Neurophysiological Monitoring / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013120:Spinal Cord Neoplasms / Q000601:surgery*
keywords: Free-running electromyography; Intramedullary spinal cord tumor; Intraoperative monitoring; Muscle motor evoked potential; Somatosensory evoked potential