title: Intraoperative neurophysiological monitoring in patients undergoing tethered cord surgery after fetal myelomeningocele repair.
abstract: OBJECTIVE
  Fetal myelomeningocele closure has been shown to be advantageous in a number of areas. In this study, the authors report on neural function in patients who had previously undergone fetal myelomeningocele repair and returned to the authors' institution for further surgery that included intraoperative neurophysiological monitoring.
  
  
  METHODS
  The authors retrospectively reviewed data obtained in 6 cases involving patients who underwent fetal myelomeningocele repair and later returned to their institution for spinal cord untethering. (In 4 of the 6 cases, the patients also underwent removal of a dermoid cyst [3 cases] or removal of an epidermoid cyst [1 case] during the untethering procedure.) Records and imaging studies were reviewed to identify the anatomical level of the myelomeningocele as well as the functional status of each patient. Stimulated electromyography (EMG) and transcranial motor evoked potential (tcMEP) recordings obtained during surgery were reviewed to assess the functional integrity of the nerve roots and spinal cord.
  
  
  RESULTS
  During reexploration, all patients had reproducible signals at or below their anatomical level on stimulated EMG and tcMEP recordings. Corresponding to these findings, prior to tethering, all patients had antigravity muscle function below their anatomical level.
  
  
  CONCLUSIONS
  All 6 patients had lower-extremity function and neurophysiological monitoring recording signals at or below their anatomical level. These cases provide direct evidence of spinal cord and nerve root conductivity and functionality below the anatomical level of the myelomeningocele, further supporting that neurological status improves with fetal repair.
authors: Department of Neurosurgery, Johns Hopkins University, Baltimore, Maryland;
authors: Eric M
authors: EM
authors: Jackson
authors: Daniel M
authors: DM
authors: Schwartz
authors: Anthony K
authors: AK
authors: Sestokas
authors: Deborah M
authors: DM
authors: Zarnow
authors: N Scott
authors: NS
authors: Adzick
authors: Mark P
authors: MP
authors: Johnson
authors: Gregory G
authors: GG
authors: Heuer
authors: Leslie N
authors: LN
authors: Sutton
mesh_terms: D002675:Child, Preschool; D003884:Dermoid Cyst / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D004576:Electromyography; D019054:Evoked Potentials, Motor; D005260:Female; D005315:Fetal Diseases / Q000601:surgery*; D006801:Humans; D007223:Infant; D064795:Intraoperative Neurophysiological Monitoring / Q000379:methods; D008279:Magnetic Resonance Imaging; D008297:Male; D008499:Medical Records; D008591:Meningomyelocele / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D009431:Neural Conduction; D009436:Neural Tube Defects / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D012086:Reoperation; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013120:Spinal Cord Neoplasms / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome