title: Electrophysiological effects of electrode pull-back in cochlear implant surgery.
abstract: CONCLUSIONS
  The surgical technique of electrode pull-back had a significant improving effect on the spread of excitation (SOE). However, the long-term clinical and audiological outcome of this modified surgical technique should be a subject of further studies.
  
  
  OBJECTIVE
  To observe the intraoperative electrophysiological effects of a surgical electrode insertion technique (i.e. pull-back) in cochlear implantation.
  
  
  METHODS
  The influence of the pull-back technique on intraoperatively recorded electrophysiological parameters (including T-NRT, ECAP amplitude, SOE) was investigated in a prospective, non-randomized, intraoperative study. In addition, we observed the correlation of insertion depth and SOE differences after a controlled electrode pull-back. We implanted 13 patients (aged 18-76 years) with a Nucleus 24CI RE cochlear implant with a perimodiolar electrode.
  
  
  RESULTS
  After a controlled pull-back, a significant decrease of the SOE at different electrodes (upon recording from electrodes 5, 10, 15) was observed. Electrode 10 was the SOE area with the most significant and homogeneous changes after pull-back. The change in the ECAP amplitudes was highly variable in correlation with the changes in the SOE.
authors.affiliation: Department of Otolaryngology at UKB, Hospital of the University of Berlin, Charité Medical School, Berlin, Germany. todt@gmx.net
authors.forename: Ingo
authors.initials: I
authors.lastname: Todt
authors.forename: Dietmar
authors.initials: D
authors.lastname: Basta
authors.forename: Rainer
authors.initials: R
authors.lastname: Seidl
authors.forename: Arne
authors.initials: A
authors.lastname: Ernst
mesh_terms: D000158:Acoustic Impedance Tests; D000293:Adolescent; D000328:Adult; D000368:Aged; D003051:Cochlea / Q000000981:diagnostic imaging / Q000601:surgery; D019929:Cochlear Implantation / Q000379:methods*; D003054:Cochlear Implants; D055724:Electrophysiological Phenomena; D006801:Humans; D008875:Middle Aged; D011446:Prospective Studies; D011859:Radiography; D055815:Young Adult