Project funding was through a grant from the Department of Otolaryngology Head and Neck Surgery, Mayo Clinic, Rochester, MN. Cochlear Corporation (Sydney, New South Wales, Australia) provided electrode arrays.
Version of Record online: 3 MAY 2011
Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.
Volume 121, Issue 7, pages 1508–1516, July 2011
How to Cite
Driscoll, C. L.W., Carlson, M. L., Fama, A. F. and Lane, J. I. (2011), Evaluation of the hybrid-L24® electrode using microcomputed tomography. The Laryngoscope, 121: 1508–1516. doi: 10.1002/lary.21837
Colin L.W. Driscoll, MD, is a consultant for Cochlear Corporation.
IRB Approval: 07-008398.
- Issue online: 16 JUN 2011
- Version of Record online: 3 MAY 2011
- Accepted manuscript online: 27 APR 2011 10:24AM EST
- Manuscript Accepted: 2 FEB 2011
- Manuscript Received: 6 JAN 2011
- Cochlear implant(s);
- electroacoustic stimulation;
- microcomputed tomography;
- CT microscopy;
- Level of Evidence: 4
To compare electrode array position, and depth of insertion of the Cochlear Hybrid-L24® electrode array following traditional cochleostomy and round window (RW) insertion.
Prospective cadaveric temporal bone study.
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.
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.
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. Laryngoscope, 2011