title: Neurophysiological evaluation of the corticospinal tract by D-wave recordings in young children.
abstract: OBJECTIVE
  The objective was to neurophysiologically evaluate corticospinal tract (CT) maturation in children younger than 36 months by recording D-waves.
  
  
  METHODS
  In 19 children, D-wave recordings were attempted during resection of intramedullary spinal cord tumors (imSCTs). D-waves were elicited by transcranial electrical stimulation (TES; single pulse, anodal stimulation) and recorded from a catheter-electrode inserted into the epidural space caudal to the imSCTs. The presence of the D-wave was analyzed in respect of the patients' age.
  
  
  RESULTS
  A D-wave was present in 7 children (21-36 months) and absent in the remaining 12 children (8-31 months). In the youngest child (21 months) the D-wave was recorded from the lower thoracic spinal cord.
  
  
  CONCLUSIONS
  These D-wave recordings indicate that in the immature CT a synchronized descending volley via fast conducting fibers is evoked by TES and can be recorded as a D-wave from the lower thoracic spinal cord at 21 months. As all D-waves have been recorded caudal to the imSCTs, it is difficult to distinguish the contributing factor affecting the D-wave recordings in children older than 21 months: the prolonged CT maturation for the lower extremities, the individual variability of CT maturation or the influence of the imSCT.
authors.affiliation: Klinik und Poliklinik für Neurochirurgie, Universitätsklinik der J.W. Goethe Universität, Haus 95, Schleusenweg 2-16, 60529 Frankfurt, Germany. A.Szelenyi@em.uni-frankfurt.de
authors.forename: Andrea
authors.initials: A
authors.lastname: Szelényi
authors.forename: Adauri
authors.initials: A
authors.lastname: Bueno de Camargo
authors.forename: Vedran
authors.initials: V
authors.lastname: Deletis
mesh_terms: D002540:Cerebral Cortex / Q000254:growth & development / Q000502:physiology; D002675:Child, Preschool; D004558:Electric Stimulation / Q000379:methods; D004566:Electrodes; D019054:Evoked Potentials, Motor; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011712:Pyramidal Tracts / Q000254:growth & development / Q000502:physiology*; D012494:Sampling Studies