title: Is intraoperative neurophysiological monitoring valuable predicting postoperative neurological recovery?
abstract: OBJECTIVE
  We investigated the ability of intraoperative neurophysiological monitoring to predict postoperative neurological recovery in intradural-extramedullary spinal cord tumors.
  
  
  METHODS
  From 2010 to 2014, we operated on 173 intradural-extramedullary spinal cord tumor patients with intraoperative neurophysiological monitoring. We retrospectively compared preoperative and postoperative clinical status using a modified McCormick grading scale and correlated with intraoperative neurophysiological monitoring. We followed patients for at least 1 year and correlated neurological outcomes with intraoperative changes in intraoperative neurophysiological monitoring. We then compared the degree of intraoperative neurophysiological monitoring change with the duration of the neurological deficit.
  
  
  RESULTS
  Monitorability was 92% and 57% with transcranial motor-evoked potential and somatosensory-evoked potential modalities, respectively. Waveform attenuation on transcranial motor-evoked potentials was detected in 8.17% of cases. For somatosensory-evoked potentials, waveform attenuation was detected in 7% of the patients. A multimodality approach incorporating any transcranial motor-evoked potential changes had a sensitivity of 0.91 and a specificity of 0.98. The McCormick grade scale increased until 1 month in patients with alarm criteria on transcranial motor-evoked potentials (P<0.05).
  
  
  CONCLUSIONS
  Patients suffered neurological deterioration in case of abolishment or >50% irreversible attenuation of the waveform in transcranial motor-evoked potentials. All patients gradually recovered after 1 postoperative month with alarm criteria from 50% to 80% irreversible amplitude drop on transcranial motor-evoked potentials.
authors.affiliation: Department of Neurosurgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Rho
authors.affiliation: Department of Neurosurgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: S C
authors.initials: SC
authors.lastname: Rhim
authors.affiliation: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: J K
authors.initials: JK
authors.lastname: Kang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019054:Evoked Potentials, Motor; D005073:Evoked Potentials, Somatosensory; D005260:Female; D006801:Humans; D064795:Intraoperative Neurophysiological Monitoring / Q000379:methods; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000379:methods; D011379:Prognosis; D020127:Recovery of Function; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013120:Spinal Cord Neoplasms / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult