title: Evaluation of the hybrid-L24 electrode using microcomputed tomography.
abstract: OBJECTIVE
  To compare electrode array position, and depth of insertion of the Cochlear Hybrid-L24 electrode array following traditional cochleostomy and round window (RW) insertion.
  
  
  METHODS
  Prospective cadaveric temporal bone study.
  
  
  METHODS
  Ten cadaveric temporal bones were implanted with the Hybrid-L24 electrode array; half were introduced through a RW approach, whereas the other half were inserted through a traditional scala tympani cochleostomy. A micro-CT scanner was then used to evaluate electrode position, intracochlear trauma, and depth of insertion.
  
  
  RESULTS
  All electrodes were inserted into the scala tympani without significant resistance. No electrodes demonstrated tip fold-over or through-fracturing of the osseous spiral lamina, basilar membrane, or spiral ligament. The average angular depth of insertion for all 10 electrodes was 252.4°. Compared to cochleostomy insertions, electrodes inserted through the RW more commonly acquired a proximal perimodiolar orientation, followed a more predictable course, and less commonly contacted critical soft tissue structures.
  
  
  CONCLUSIONS
  The results of this study demonstrate that the Hybrid-L24 electrode can be successfully inserted using a RW or traditional cochleostomy technique with minimal intracochlear trauma. Our data also suggests that with this model, RW insertions may provide particular advantages with respect to hearing preservation over the traditional cochleostomy approach.
authors.affiliation: Department of Otorhinolaryngology Head and Neck Surgery & Department of Radiology, Mayo Clinic School of Medicine, Rochester, Minnesota 55905, USA. driscoll.colin@mayo.edu
authors.forename: Colin L W
authors.initials: CL
authors.lastname: Driscoll
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Carlson
authors.forename: Anthony F
authors.initials: AF
authors.lastname: Fama
authors.forename: John I
authors.initials: JI
authors.lastname: Lane
mesh_terms: D002102:Cadaver; D019929:Cochlear Implantation / Q000379:methods*; D016001:Confidence Intervals; D004567:Electrodes, Implanted; D004867:Equipment Design; D004869:Equipment Safety; D005260:Female; D006801:Humans; D008297:Male; D016017:Odds Ratio; D011446:Prospective Studies; D012405:Round Window, Ear / Q000601:surgery*; D013701:Temporal Bone / Q000601:surgery*; D055114:X-Ray Microtomography / Q000295:instrumentation*