Latest research on cochlear implantations focuses on hearing preservation during insertion of the implant’s electrode array by reducing insertion trauma. One parameter which may influence trauma is insertion speed. The objective of this study was to extend the range of examined insertion speeds to include ultra-low velocities, being lower than manually feasible, and investigate whether these reduce insertion forces.
24 custom-made cochlear implant test samples were fabricated and inserted into an artificial scala tympani model using 12 different insertion speeds while measuring the resulting insertion forces. Three commercially available slim straight electrode carriers were inserted using the same setup to analyze whether the results are comparable.
Insertions of the test samples using high insertion speeds (2.0/2.8 mm/s) showed significantly higher insertion forces than insertions done with low insertion speeds (0.2 mm/s) or ultra-low insertion speeds (< 0.1 mm/s). The insertions with commercial slim straight electrode arrays showed significantly reduced insertion forces when using a low insertion speed as well.
Slow insertions showed significantly reduced insertion forces. Insertion speeds which are lower than manually feasible showed even lower insertion forces.
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Hoskison E, Mitchell S, Coulson C (2017) Systematic review: radiological and histological evidence of cochlear implant insertion trauma in adult patients. Cochlear Impl Int 18:192–197
Roland PS, Wright CG (2006) Surgical aspects of cochlear implantation: mechanisms of insertional trauma. Cochlear Brainstem Impl 64:11–30
Mirsalehi M, Rau TS, Harbach L et al (2017) Insertion forces and intracochlear trauma in temporal bone specimens implanted with a straight atraumatic electrode array. Eur Arch Otorhinolaryngol 5:2131–2140
Avci E, Nauwelaers T, Hamacher V, Kral A (2017) Three-dimensional force profile during cochlear implantation depends on individual geometry and insertion trauma. Ear Hear 38:e168–e179
Zhang J, Bhattacharyya S, Simaan N (2009) Model and parameter identification of friction during robotic insertion of cochlear-implant electrode arrays. IEEE international conference on robotics and automation ICRA, pp 3859–3864
Kontorinis G, Lenarz T, Stöver T, Paasche G (2011) Impact of the insertion speed of cochlear implant electrodes on the insertion forces. Otol Neurotol 32:565–570
Rajan GP, Kontorinis G, Kuthubutheen J (2013) The effects of insertion speed on inner ear function during cochlear implantation: a comparison study. Audiol Neurootol 18:17–22
Majdani O, Schurzig D, Hussong A et al (2010) Force measurement of insertion of cochlear implant electrode arrays in vitro: comparison of surgeon to automated insertion tool. Acta Otolaryngol 130:31–36
Rau TS, Hussong A, Leinung M, Lenarz T, Majdani O (2010) Automated insertion of preformed cochlear implant electrodes: evaluation of curling behaviour and insertion forces on an artificial cochlear model. Int J Comput Assist Radiol Surg 5:173–181
Berman AD, Ducker WA, Israelachvili JN (1996) Origin and characterization of different stick-slip friction mechanisms. Langmuir 12(19):4559–4563
Gantz BJ, Turner C, Gfeller KE, Lowder MW (2005) Preservation of hearing in cochlear implant surgery: advantages of combined electrical and acoustical speech processing. Laryngoscope 115:796–802
Büchner A, Schüssler M, Battmer RD, Stöver T, Lesinski-Schiedat A, Lenarz T (2009) Impact of low-frequency hearing. Audiol Neurootol 14(suppl 1):8–13
Von Ilberg CA, Baumann U, Kiefer J, Tillein J, Adunka OF (2011) Electric-acoustic stimulation of the auditory system: a review of the first decade. Audiol Neurootol 16(suppl. 2):1–30
Roland PS, Gstöttner W, Adunka O (2005) Method for hearing preservation in cochlear implant surgery. Oper Tech Otolayngol Head Neck Surg 16(2):93–100
Hüttenbrink KB, Zahnert T, Jolly C, Hofmann G (2002) Movements of cochlear implant electrodes inside the cochlea during insertion: an X-ray microscopy study. Otol Neurotol 23:187–191
Cohen LT, Xu J, Xu SA, Clark GM (1996) Improved and simplified methods for specifying positions of the electrode bands of a cochlear implant array. Am J Otol 17:859–865
Todd CA, Naghdy F, Svehla MJ (2007) Force application during cochlear implant insertion: an analysis for improvement of surgeon technique. IEEE Trans Biomed Eng 54:1247–1255
Kontorinis G, Paasche G, Lenarz T, Stöver T (2011) The effect of different lubricants on cochlear implant electrode insertion forces. Otol Neurotol 32:1050–1056
Kobler JP, Dhanasingh A, Kiran R, Jolly C, Ortmaier T (2015) Cochlear dummy electrodes for insertion training and research purposes: fabrication, mechanical characterization, and experimental validation. Bio Med Res Int 2015:574209. https://doi.org/10.1155/2015/574209
Roland JT (2005) A model for cochlear implant electrode insertion and force evaluation: results with a new electrode design and insertion technique. Laryngoscope 115:1325–1339
Radeloff A, Unkelbach MH, Mack MG et al (2009) A coated electrode carrier for cochlear implantation reduces insertion forces. Laryngoscope 119:959–963
Helbig S, Settevendemie C, Mack M, Baumann U, Helbig M, Stöver T (2011) Evaluation of an electrode prototype for atraumatic cochlear implantation in hearing preservation candidates: preliminary results from a temporal bone study. Otol Neurotol 32:419–423
Miroir M, Nguyen Y, Kazmitcheff G, Ferrary E, Sterkers O, Grayeli AB (2012) Friction force measurement during cochlear implant insertion: application to a force-controlled insertion tool design. Otol Neurotol 33:1092–1100
Nguyen Y, Miroir M, Kazmitcheff G et al (2012) Cochlear implant insertion forces in microdissected human cochlea to evaluate a prototype array. Audiol Neurootol 17:290–298
Nguyen Y, Kazmitcheff G, De Seta D, Miroir M, Ferrary E, Sterkers O (2014) Definition of metrics to evaluate cochlear array insertion forces performed with forceps, insertion tool, or motorized tool in temporal bone specimens. Bio Med Res Int 2014:532570. https://doi.org/10.1155/2014/532570
Todt I, Mittmann P, Ernst A (2014) Intracochlear fluid pressure changes related to the insertional speed of a CI electrode. Bio Med Res Int 2014:507241. https://doi.org/10.1155/2014/507241
Todt I, Ernst A, Mittmann P (2016) Effects of different insertion techniques of a cochlear implant electrode on the intracochlear pressure. Audiol Neurootol 21:30–37
De Seta D, Torres R, Russo FY et al (2017) Damage to inner ear structure during cochlear implantation: correlation between insertion force and radio-histological findings in temporal bone specimens. Hear Res 344:90–97
Schurzig D, Webster RJ III, Dietrich MS, Labadie RF (2010) Force of cochlear implant electrode insertion performed by a robotic insertion tool: comparison of traditional versus advance off-stylet techniques. Otol Neurotol 31:1207–1210
Briggs RJ, Tykocinski M, Lazsig R et al (2011) Development and evaluation of the modiolar research array—multi-centre collaborative study in human temporal bones. Cochlear Impl Int 12:129–139
Hussong A, Rau TS, Ortmaier T, Heimann B, Lenarz T, Majdani O (2010) An automated insertion tool for cochlear implants: another step towards atraumatic cochlear implant surgery. Int J Comput Assist Radiol Surg 5:163–171
Balster S, Wenzel GI, Warnecke A, Steffens M, Rettenmaier A, Zhang K, Lenarz T, Reuter G (2013) Optical cochlear implant: evaluation of insertion forces of optical fibres in a cochlear model and of traumata in human temporal bones. Biomed Tech (Berl) 59(1):19–28
Nada I, Abdelhamid AN, Negm A (2017) The utilization of round window membrane surface tension in facilitating slim electrodes insertion during cochlear implantation. Eur Arch Otorhinolaryngol 274(9):3327–3334
Ishii T, Takayama M, Takahashi Y (1995) Mechanical properties of human round window, basilar and Reissner’s membranes. Acta Otolaryngol 115(sup519):78–82
Schuster D, Kratchman LB, Labadie RF (2015) Characterization of intracochlear rupture forces in fresh human cadaveric cochleae. Otol Neurotol 36(4):657
Kratchman LB, Schuster D, Dietrich MS, Labadie RF (2016) Force perception thresholds in Cochlear implantation surgery. Audiol Neurootol 21(4):244–249
Kesler K, Dillon NP, Fichera L, Labadie RF (2017) Human kinematics of cochlear implant surgery: an investigation of insertion micro-motions and speed limitations. Otolaryngol Head Neck Surg 157(3):493–498
Rau TS, Hügl S, Salcher R, Lenarz T, Majdani O (2017) Hydraulisch automatisierte Elektrodeninsertion. Presented at the 16th annual meeting of the German Society for Computer and Robot assisted Surgery (CURAC), Hannover, Germany, October 5–7
The authors would like to thank the German Research Foundation (DFG) for funding this research (support code: MA 4038/9-1). Furthermore, the authors thank Samuel Müller (Institute of Mechatronic Systems, Leibniz University Hannover) for fabrication of the casting mold.
Conflict of interest
Thomas Lenarz is a consultant for Cochlear Ltd. Silke Hügl, Katharina Rülander, Omid Majdani and Thomas S. Rau declare that they have no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
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Hügl, S., Rülander, K., Lenarz, T. et al. Investigation of ultra-low insertion speeds in an inelastic artificial cochlear model using custom-made cochlear implant electrodes. Eur Arch Otorhinolaryngol 275, 2947–2956 (2018). https://doi.org/10.1007/s00405-018-5159-1
- Electrode carrier
- Automated insertion
- Insertion tool
- Insertion force
- Cochlea implantation