Human Histology after Structure Preservation Cochlear Implantation via Round Window Insertion
Alexander Geerardyn MD
Department of Otolaryngology—Head & Neck Surgery, Harvard Medical School, Boston, Massachusetts, U.S.A.
Otopathology Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts, U.S.A.
ExpORL, Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
Search for more papers by this authorMengYu Zhu MS
Otopathology Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts, U.S.A.
Search for more papers by this authorTim Klabbers MD
Department of Otorhinolaryngology, Radboudumc, Nijmegen, the Netherlands
Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
Search for more papers by this authorWendy Huinck PhD
Department of Otorhinolaryngology, Radboudumc, Nijmegen, the Netherlands
Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
Search for more papers by this authorEmmanuel Mylanus MD, PhD
Department of Otorhinolaryngology, Radboudumc, Nijmegen, the Netherlands
Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
Search for more papers by this authorJoseph B. Nadol Jr MD
Department of Otolaryngology—Head & Neck Surgery, Harvard Medical School, Boston, Massachusetts, U.S.A.
Otopathology Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts, U.S.A.
Search for more papers by this authorNicolas Verhaert MD, PhD
ExpORL, Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
Search for more papers by this authorCorresponding Author
Alicia M. Quesnel MD
Department of Otolaryngology—Head & Neck Surgery, Harvard Medical School, Boston, Massachusetts, U.S.A.
Otopathology Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts, U.S.A.
Send correspondence to Alicia M. Quesnel, Department of Otolaryngology—Head & Neck Surgery, Harvard Medical School, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA 02114. Email: [email protected]
Search for more papers by this authorAlexander Geerardyn MD
Department of Otolaryngology—Head & Neck Surgery, Harvard Medical School, Boston, Massachusetts, U.S.A.
Otopathology Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts, U.S.A.
ExpORL, Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
Search for more papers by this authorMengYu Zhu MS
Otopathology Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts, U.S.A.
Search for more papers by this authorTim Klabbers MD
Department of Otorhinolaryngology, Radboudumc, Nijmegen, the Netherlands
Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
Search for more papers by this authorWendy Huinck PhD
Department of Otorhinolaryngology, Radboudumc, Nijmegen, the Netherlands
Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
Search for more papers by this authorEmmanuel Mylanus MD, PhD
Department of Otorhinolaryngology, Radboudumc, Nijmegen, the Netherlands
Donders Institute for Brain, Cognition and Behaviour, Nijmegen, the Netherlands
Search for more papers by this authorJoseph B. Nadol Jr MD
Department of Otolaryngology—Head & Neck Surgery, Harvard Medical School, Boston, Massachusetts, U.S.A.
Otopathology Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts, U.S.A.
Search for more papers by this authorNicolas Verhaert MD, PhD
ExpORL, Department of Neurosciences, Katholieke Universiteit Leuven, Leuven, Belgium
Search for more papers by this authorCorresponding Author
Alicia M. Quesnel MD
Department of Otolaryngology—Head & Neck Surgery, Harvard Medical School, Boston, Massachusetts, U.S.A.
Otopathology Laboratory, Massachusetts Eye and Ear, Boston, Massachusetts, U.S.A.
Send correspondence to Alicia M. Quesnel, Department of Otolaryngology—Head & Neck Surgery, Harvard Medical School, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA 02114. Email: [email protected]
Search for more papers by this authorNicolas Verhaert and Alicia M. Quesnel contributed equally to this work and share last authorship.
This work was financially supported by Research Foundation Flanders (FWO: 1SD3322N(AG), V414121N(AG), 1804816N(NV), G088619N(NV)) and NIH (U24DC013983(AMQ), U24DC020849(AMQ)).
Alicia M. Quesnel, MD: Grace Medical—sponsored research agreement; Frequency Therapeutics—sponsored research agreement, consulting; Alcon—consulting. The department of Tim Klabbers MD, Wendy Huinck PhD and Emmanuel Mylanus MD PhD currently receives ongoing institutional grants from Cochlear Ltd. and Oticon Medical but not specifically for this study. The other co-authors have no conflicts of interest to declare.
Abstract
Objectives
Current surgical techniques aim to preserve intracochlear structures during cochlear implant (CI) insertion to maintain residual cochlear function. The optimal technique to minimize damage, however, is still under debate. The aim of this study is to histologically compare insertional trauma and intracochlear tissue formation in humans with a CI implanted via different insertion techniques.
Methods
One recent temporal bone from a donor who underwent implantation of a full-length CI (576°) via round window (RW) insertion was compared with nine cases implanted via cochleostomy (CO) or extended round window (ERW) approach. Insertional trauma was assessed on H&E-stained histological sections. 3D reconstructions were generated and virtually re-sectioned to measure intracochlear volumes of fibrosis and neo-ossification.
Results
The RW insertion case showed electrode translocation via the spiral ligament. 2/9 CO/ERW cases showed no insertional trauma. The total volume of the cochlea occupied by fibro-osseous tissue was 10.8% in the RW case compared with a mean of 30.6% (range 8.7%–44.8%, N = 9) in the CO/ERW cases. The difference in tissue formation in the basal 5 mm of scala tympani, however, was even more pronounced when the RW case (12.3%) was compared with the cases with a CO/ERW approach (mean of 93.8%, range 81% to 100%, N = 9).
Conclusions
Full-length CI insertions via the RW can be minimally traumatic at the cochlear base without inducing extensive fibro-osseous tissue formation locally. The current study further supports the hypothesis that drilling of the cochleostomy with damage to the endosteum incites a local tissue reaction.
Level of Evidence
4: Case–control study Laryngoscope, 134:945–953, 2024
Supporting Information
Filename | Description |
---|---|
lary30900-sup-0001-SupplementaryFigure.tifTIFF image, 165.9 MB | Figure S1. Mid-Modiolar Sections. *: electrode array location; +: fibrosis; ++: ossification. |
lary30900-sup-0002-SupplementaryTable.docxWord 2007 document , 23.5 KB | Table S1. Qualitative description of fibrosis, ossification, and hydrops. R: right, L: left, RW: round window, ERW: extended round window, ST: scala tympani, and SV: scala vestibuli. |
lary30900-sup-0003-SupplementaryVideo.mp4MPEG-4 video, 136.9 MB | Supplementary Video. Rotating 3D reconstructions. Yellow: cochlear implant electrode. Red: round window membrane. Blue: normal perilymph. Gray: fibrosis. White: bone. |
Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
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