OBJECTIVE: The insertion of the electrode array is a critical step in cochlear implantation. Herein we comprehensively investigate the impact of the alignment angle and feed-forward speed on deep insertions in artificial scala tympani models with accurate macro-anatomy and controlled frictional properties. METHODS: Motorized insertions (n=1033) were performed in six scala tympani models with varying speeds and alignment angles. We evaluated reaction forces and micrographs of the insertion process and developed a mathematical model to estimate the normal force distribution along the electrode arrays. RESULTS: Insertions parallel to the cochlear base significantly reduce insertion energies and lead to smoother array movement. Non-constant insertion speeds allow to reduce insertion forces for a fixed total insertion time compared to a constant feed rate. CONCLUSION: In cochlear implantation, smoothness and peak forces can be reduced with alignment angles parallel to the scala tympani centerline and with non-constant feed-forward speed profiles. SIGNIFICANCE: Our results may help to provide clinical guidelines and improve surgical tools for manual and automated cochlear implantation.
OBJECTIVE: The insertion of the electrode array is a critical step in cochlear implantation. Herein we comprehensively investigate the impact of the alignment angle and feed-forward speed on deep insertions in artificial scala tympani models with accurate macro-anatomy and controlled frictional properties. METHODS: Motorized insertions (n=1033) were performed in six scala tympani models with varying speeds and alignment angles. We evaluated reaction forces and micrographs of the insertion process and developed a mathematical model to estimate the normal force distribution along the electrode arrays. RESULTS: Insertions parallel to the cochlear base significantly reduce insertion energies and lead to smoother array movement. Non-constant insertion speeds allow to reduce insertion forces for a fixed total insertion time compared to a constant feed rate. CONCLUSION: In cochlear implantation, smoothness and peak forces can be reduced with alignment angles parallel to the scala tympani centerline and with non-constant feed-forward speed profiles. SIGNIFICANCE: Our results may help to provide clinical guidelines and improve surgical tools for manual and automated cochlear implantation.
Authors: Paul Van de Heyning; Peter Roland; Luis Lassaletta; Sumit Agrawal; Marcus Atlas; Wolf-Dieter Baumgartner; Kevin Brown; Marco Caversaccio; Stefan Dazert; Wolfgang Gstoettner; Rudolf Hagen; Abdulrahman Hagr; Greg Eigner Jablonski; Mohan Kameswaran; Vladislav Kuzovkov; Martin Leinung; Yongxin Li; Andreas Loth; Astrid Magele; Robert Mlynski; Joachim Mueller; Lorne Parnes; Andreas Radeloff; Chris Raine; Gunesh Rajan; Joachim Schmutzhard; Henryk Skarzynski; Piotr H Skarzynski; Georg Sprinzl; Hinrich Staecker; Timo Stöver; Dayse Tavora-Viera; Vedat Topsakal; Shin-Ichi Usami; Vincent Van Rompaey; Nora M Weiss; Wilhelm Wimmer; Mario Zernotti; Javier Gavilan Journal: Front Surg Date: 2022-03-24