title: Cochlear implant-evoked cortical activation in children with cochlear nerve deficiency.
abstract: OBJECTIVE
  To report the results of cochlear implant-elicited cortical auditory evoked potentials (eCAEP) in children with cochlear nerve deficiency (CND).
  
  
  METHODS
  Case control series.
  
  
  METHODS
  Tertiary academic referral center.
  
  
  METHODS
  Seven children with CND that have a cochlear implant in their affected ear. Four children without CND served as controls.
  
  
  METHODS
  eCAEPs were elicited by activation of individual cochlear implant electrodes.
  
  
  METHODS
  Onset responses (P1-N1-P2 complex).
  
  
  RESULTS
  Three of 7 CND children demonstrated eCAEP responses across a broad range of electrodes despite having limited or no open set speech perception abilities using their implants. Two of these children had eCAEPs that were characterized by substantial variability in latency, amplitude, and number of electrodes with identifiable responses. The remaining 4 ears with CND and poor speech perception had multiphasic responses that are inconsistent with eCAEPs. Non-CND ears with excellent speech perception abilities demonstrated robust responses on all electrodes stimulated.
  
  
  CONCLUSIONS
  Abent eCAEP responses were indicative of poor open-set speech perception skills in all cases. However, eCAEP onset responses were measurable in some children with imaging evidence of CND, indicating probable cochlear nerve hypoplasia rather than aplasia. That some children with CND and poor speech perception had robust eCAEPs in some instances makes this particular measure of limited use for predicting good speech perception outcomes after cochlear implantation in these children. The origin of multiphasic responses remains to be determined but may be of somatosensory origin in some instances.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7600, USA.
authors.forename: Shuman
authors.initials: S
authors.lastname: He
authors.forename: John
authors.initials: J
authors.lastname: Grose
authors.forename: Anna X
authors.initials: AX
authors.lastname: Hang
authors.forename: Craig A
authors.initials: CA
authors.lastname: Buchman
mesh_terms: D000293:Adolescent; D001299:Audiometry; D001303:Auditory Cortex / Q000503:physiopathology*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003054:Cochlear Implants; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000503:physiopathology*; D006801:Humans; D008297:Male; D013067:Speech Perception / Q000502:physiology; D000160:Vestibulocochlear Nerve Diseases / Q000503:physiopathology*