title: Effect of peripheral nerve tetanic stimulation on the inter-trial variability and accuracy of transcranial motor-evoked potential in brain surgery.
abstract: OBJECTIVE
  The aim of this study was to evaluate and compare the advantages of post-tetanic motor-evoked potential (p-MEP) and conventional motor-evoked potential (c-MEP) in terms of MEP inter-trial variability and accuracy.
  
  
  METHODS
  c-MEP and p-MEP were quantified in subjects who underwent brain surgery. c-MEP was generated by transcranial electrical stimulation (TES). p-MEP was generated using a preconditioning process involving tetanic stimulation at the left tibial nerve followed by TES. The presence of significant MEP deterioration was monitored during major surgical process. An additional 5-8 MEP obtained after major surgical process were used to analyze amplitude parameters such as mean, standard deviation, range, coefficient of variation (CV), and range to mean ratio.
  
  
  RESULTS
  When only irreversible MEP deteriorations were considered as positive results, the false-positive rate was identical for p-MEP and c-MEP. When total MEP deteriorations were considered as positive results, the false-positive rate of p-MEP was lower and p-MEP had higher specificity than c-MEP. The mean amplitude of p-MEP was significantly higher than that of c-MEP. The CV and range to mean ratio of p-MEP were less than those of c-MEP.
  
  
  CONCLUSIONS
  The p-MEP technique is useful for augmenting MEP amplitude and reducing inter-trial variability.
  
  
  CONCLUSIONS
  p-MEP has clinical significance as a useful technique for intraoperative monitoring.
authors.affiliation: Department of Neurology, Korea University Guro Hospital, Seoul, South Korea.
authors.forename: Ji-Sun
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Youngdoo
authors.initials: Y
authors.lastname: Choi
authors.affiliation: Department of Neurosurgery, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Seung-Hyun
authors.initials: SH
authors.lastname: Jin
authors.affiliation: Department of Neurosurgery, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Chi Heon
authors.initials: CH
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Chul-Kee
authors.initials: CK
authors.lastname: Park
authors.affiliation: Department of Neurology, Seoul National University Hospital, Seoul, South Korea. Electronic address: 81100@snuh.org.
authors.forename: Sung-Min
authors.initials: SM
authors.lastname: Kim
authors.affiliation: Department of Neurology, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Kwang-Woo
authors.initials: KW
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Chun Kee
authors.initials: CK
authors.lastname: Chung
authors.affiliation: Department of Neurosurgery, Seoul National University Hospital, Seoul, South Korea.
authors.forename: Sun Ha
authors.initials: SH
authors.lastname: Paek
mesh_terms: D000328:Adult; D001921:Brain / Q000601:surgery*; D004365:Drugs, Chinese Herbal; D004558:Electric Stimulation / Q000379:methods*; D028001:Eleutherococcus; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D012189:Retrospective Studies; D013238:Stereotaxic Techniques; D013979:Tibial Nerve / Q000502:physiology*; D065908:Transcranial Direct Current Stimulation
chemical_list: D004365:Drugs, Chinese Herbal; C400150:Acanthopanax gracilistylus, extract
keywords: Intraoperative monitoring; Peripheral nerve tetanic stimulation; Post-tetanic motor-evoked potential