European Archives of Oto-Rhino-Laryngology

, Volume 273, Issue 12, pp 4251–4256 | Cite as

Electrophysiological detection of scalar changing perimodiolar cochlear electrode arrays: a long term follow-up study

  • Philipp MittmannEmail author
  • I. Todt
  • A. Ernst
  • G. Rademacher
  • S. Mutze
  • S. Göricke
  • M. Schlamann
  • R. Ramalingam
  • S. Lang
  • F. Christov
  • D. Arweiler-Harbeck


The position of the cochlear electrode array within the scala tympani is essential for an optimal hearing benefit. An intraoperative NRT-ratio was established, which can provide information about the intraoperative intracochlear electrode array position for perimodiolar electrodes. The aims of this study were to verify the longterm reliability for the NRT-ratio in perimodiolar electrodes. In a retrospective controlled study in a Tertiary Referral Center the electrophysiological data sets of 123 patients with implanted Nucleus Contour Advance electrodes were enclosed. Intraoperative and up to 1 year follow-up Auto-NRTs were evaluated. A NRT-ratio was calculated by dividing the average Auto-NRT data from electrode 16 to 18 with the average from electrode 5 to 7. Using a flat panel tomography system, the position of the electrode array was certified radiological. 31 patients with perimodiolar electrodes with 1 year follow-up data were included in the study. Eleven patients showed regular follow-up NRT-ratio with a correlated and radiologically confirmed electrode position. 20 patients showed mismatches between the NRT-ratio and the radiological position. These patients were highly variable in terms of duration of deafness and neural spectrum disorders. The NRT-ratio can be used to determine the intracochlear position of the electrode array for perimodiolar electrodes. Intraoperatively the NRT-ratio predicts the array position within the cochlea highly reliable for perimodiolar electrodes. We showed that after 6 months and a year, the NRT-ratio remains unchanged in most of the cases and shows a good correlation to the radiological determined position of the array. Nevertheless, the condition of the neural structures is highly important for reproducible responses. Limited validity is given in patients with degenerative and structural neural disorders.


Cochlear implant NRT Radiology Quality control 



This study was funded by Cochlear Pty. Sydney, Australia (IIR 1209).

Compliance with ethical standards

Conflict of interest

The Unfallkrankenhaus Berlin received research grants from Cochlear Pty.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. For this type of study formal consent is not required.


  1. 1.
    Adunka O, Kiefer J (2006) Impact of electrode insertion depth on intracochlear trauma. Otolaryngol Head Neck Surg 135(3):374–382. doi: 10.1016/j.otohns.2006.05.002 CrossRefPubMedGoogle Scholar
  2. 2.
    Kiefer J, Gstoettner W, Baumgartner W, Pok SM, Tillein J, Ye Q, von Ilberg C (2004) Conservation of low-frequency hearing in cochlear implantation. Acta Otolaryngol 124(3):272–280CrossRefPubMedGoogle Scholar
  3. 3.
    Aschendorff A, Kromeier J, Klenzner T, Laszig R (2007) Quality control after insertion of the nucleus contour and contour advance electrode in adults. Ear Hear 28(2 Suppl):75S–79S. doi: 10.1097/AUD.0b013e318031542e CrossRefPubMedGoogle Scholar
  4. 4.
    Finley CC, Holden TA, Holden LK, Whiting BR, Chole RA, Neely GJ, Hullar TE, Skinner MW (2008) Role of electrode placement as a contributor to variability in cochlear implant outcomes. Otol Neurotol 29(7):920–928. doi: 10.1097/MAO.0b013e318184f492 CrossRefPubMedPubMedCentralGoogle Scholar
  5. 5.
    Carelsen B, Grolman W, Tange R, Streekstra GJ, van Kemenade P, Jansen RJ, Freling NJ, White M, Maat B, Fokkens WJ (2007) Cochlear implant electrode array insertion monitoring with intra-operative 3D rotational X-ray. Clin Otolaryngol 32(1):46–50. doi: 10.1111/j.1365-2273.2007.01319.x CrossRefPubMedGoogle Scholar
  6. 6.
    Trieger A, Schulze A, Schneider M, Zahnert T, Murbe D (2011) In vivo measurements of the insertion depth of cochlear implant arrays using flat-panel volume computed tomography. Otol Neurotol 32(1):152–157. doi: 10.1097/MAO.0b013e3181fcf04d CrossRefPubMedGoogle Scholar
  7. 7.
    Kong WJ, Cheng HM, Ma H, Wang YJ, Han P (2012) Evaluation of the implanted cochlear implant electrode by CT scanning with three-dimensional reconstruction. Acta Otolaryngol 132(2):116–122. doi: 10.3109/00016489.2011.626794 CrossRefPubMedGoogle Scholar
  8. 8.
    Svrakic M, Friedmann DR, Berman PM, Davis AJ, Roland JT Jr, Svirsky MA (2015) Measurement of cochlear implant electrode position from intraoperative post-insertion skull radiographs: a validation study. Otol Neurotol 36(9):1486–1491. doi: 10.1097/MAO.0000000000000852 CrossRefPubMedPubMedCentralGoogle Scholar
  9. 9.
    Skinner MW, Holden TA, Whiting BR, Voie AH, Brunsden B, Neely JG, Saxon EA, Hullar TE, Finley CC (2007) In vivo estimates of the position of advanced bionics electrode arrays in the human cochlea. Ann Otol Rhinol Laryngol Suppl 197:2–24CrossRefPubMedGoogle Scholar
  10. 10.
    Holden LK, Finley CC, Firszt JB, Holden TA, Brenner C, Potts LG, Gotter BD, Vanderhoof SS, Mispagel K, Heydebrand G, Skinner MW (2013) Factors affecting open-set word recognition in adults with cochlear implants. Ear Hear 34(3):342–360. doi: 10.1097/AUD.0b013e3182741aa7 CrossRefPubMedPubMedCentralGoogle Scholar
  11. 11.
    Aschendorff A, Kubalek R, Turowski B, Zanella F, Hochmuth A, Schumacher M, Klenzner T, Laszig R (2005) Quality control after cochlear implant surgery by means of rotational tomography. Otol Neurotol 26(1):34–37CrossRefPubMedGoogle Scholar
  12. 12.
    Davis TJ, Zhang D, Gifford RH, Dawant BM, Labadie RF, Noble JH (2016) Relationship between electrode-to-modiolus distance and current levels for adults with cochlear implants. Otol Neurotol 37(1):31–37. doi: 10.1097/MAO.0000000000000896 CrossRefPubMedGoogle Scholar
  13. 13.
    Seidman MD, Vivek P, Dickinson W (2005) Neural response telemetry results with the nucleus 24 contour in a perimodiolar position. Otol Neurotol 26(4):620–623CrossRefPubMedGoogle Scholar
  14. 14.
    Gordon KA, Papsin BC (2013) From nucleus 24 to 513: changing cochlear implant design affects auditory response thresholds. Otol Neurotol 34(3):436–442. doi: 10.1097/MAO.0b013e3182804784 CrossRefPubMedGoogle Scholar
  15. 15.
    Shepherd RK, Hatsushika S, Clark GM (1993) Electrical stimulation of the auditory nerve: the effect of electrode position on neural excitation. Hear Res 66(1):108–120CrossRefPubMedGoogle Scholar
  16. 16.
    Wanna GB, Noble JH, Gifford RH, Dietrich MS, Sweeney AD, Zhang D, Dawant BM, Rivas A, Labadie RF (2015) Impact of intrascalar electrode location, electrode type, and angular insertion depth on residual hearing in cochlear implant patients: preliminary results. Otol Neurotol 36(8):1343–1348. doi: 10.1097/MAO.0000000000000829 CrossRefPubMedGoogle Scholar
  17. 17.
    Boyer E, Karkas A, Attye A, Lefournier V, Escude B, Schmerber S (2015) Scalar localization by cone-beam computed tomography of cochlear implant carriers: a comparative study between straight and periomodiolar precurved electrode arrays. Otol Neurotol 36(3):422–429. doi: 10.1097/MAO.0000000000000705 CrossRefPubMedGoogle Scholar
  18. 18.
    Mittmann P, Rademacher G, Mutze S, Hassepass F, Ernst A, Todt I (2015) Evaluation of the relationship between the NRT-ratio, cochlear anatomy, and insertions depth of perimodiolar cochlear implant electrodes. BioMed Res Int 2015:706253. doi: 10.1155/2015/706253 CrossRefPubMedPubMedCentralGoogle Scholar
  19. 19.
    Mittmann P, Ernst A, Todt I (2015) Intraoperative electrophysiologic variations caused by the scalar position of cochlear implant electrodes. Otol Neurotol. doi: 10.1097/MAO.0000000000000736 Google Scholar
  20. 20.
    Mittmann P, Todt I, Wesarg T, Arndt S, Ernst A, Hassepass F (2015) Electrophysiological detection of intracochlear scalar changing perimodiolar cochlear implant electrodes: a blinded study. Otol Neurotol. doi: 10.1097/MAO.0000000000000766 Google Scholar
  21. 21.
    Henkin Y, Kaplan-Neeman R, Kronenberg J, Migirov L, Hildesheimer M, Muchnik C (2006) A longitudinal study of electrical stimulation levels and electrode impedance in children using the Clarion cochlear implant. Acta Otolaryngol 126(6):581–586. doi: 10.1080/00016480500443391 CrossRefPubMedGoogle Scholar
  22. 22.
    Birman CS, Sanli H, Gibson WP, Elliott EJ (2014) Impedance, neural response telemetry, and speech perception outcomes after reimplantation of cochlear implants in children. Otol Neurotol 35(8):1385–1393. doi: 10.1097/MAO.0000000000000362 CrossRefPubMedGoogle Scholar
  23. 23.
    Mittmann P, Todt I, Wesarg T, Arndt S, Ernst A, Hassepass F (2015) Electrophysiological detection of scalar-changing perimodiolar cochlear electrode arrays: a six-month follow-up study. Audiol Neurootol 20(6):400–405. doi: 10.1159/000441346 CrossRefPubMedGoogle Scholar
  24. 24.
    Kawano A, Seldon HL, Clark GM, Ramsden RT, Raine CH (1998) Intracochlear factors contributing to psychophysical percepts following cochlear implantation. Acta Otolaryngol 118(3):313–326CrossRefPubMedGoogle Scholar
  25. 25.
    Chen JK, Chuang AY, Sprinzl GM, Tung TH, Li LP (2013) Impedance and electrically evoked compound action potential (ECAP) drop within 24 hours after cochlear implantation. PLoS One 8(8):e71929. doi: 10.1371/journal.pone.0071929 CrossRefPubMedPubMedCentralGoogle Scholar
  26. 26.
    Henkin Y, Kaplan-Neeman R, Muchnik C, Kronenberg J, Hildesheimer M (2003) Changes over time in electrical stimulation levels and electrode impedance values in children using the Nucleus 24 M cochlear implant. Int J Pediatr Otorhinolaryngol 67(8):873–880CrossRefPubMedGoogle Scholar
  27. 27.
    Clark GM, Clark JC, Furness JB (2013) The evolving science of cochlear implants. JAMA J Am Med Assoc 310(12):1225–1226. doi: 10.1001/jama.2013.278142 CrossRefGoogle Scholar
  28. 28.
    Migirov L, Kronenberg J, Volkov A (2011) Local tissue response to cochlear implant device housings. Otol Neurotol Off Publ Am Otol Soc Am Neurotol Soc Eur Acad Otol Neurotol 32(1):55–57. doi: 10.1097/MAO.0b013e3182009d5f CrossRefGoogle Scholar
  29. 29.
    Nadol JB Jr, Eddington DK (2004) Histologic evaluation of the tissue seal and biologic response around cochlear implant electrodes in the human. Otol Neurotol Off Publ Am Otol Soc Am Neurotol Soc Eur Acad Otol Neurotol 25(3):257–262CrossRefGoogle Scholar
  30. 30.
    Brown CJ, Abbas PJ, Etlert CP, O’Brient S, Oleson JJ (2010) Effects of long-term use of a cochlear implant on the electrically evoked compound action potential. J Am Acad Audiol 21(1):5–15CrossRefPubMedPubMedCentralGoogle Scholar
  31. 31.
    Saunders E, Cohen L, Aschendorff A, Shapiro W, Knight M, Stecker M, Richter B, Waltzman S, Tykocinski M, Roland T, Laszig R, Cowan R (2002) Threshold, comfortable level and impedance changes as a function of electrode-modiolar distance. Ear Hear 23(1 Suppl):28S–40SCrossRefPubMedGoogle Scholar
  32. 32.
    Linthicum FH Jr, Fayad JN (2009) Spiral ganglion cell loss is unrelated to segmental cochlear sensory system degeneration in humans. Otol Neurotol 30(3):418–422CrossRefPubMedPubMedCentralGoogle Scholar
  33. 33.
    Shah P, Riphagen S, Beyene J, Perlman M (2004) Multiorgan dysfunction in infants with post-asphyxial hypoxic-ischaemic encephalopathy. Arch Dis Child Fetal Neonatal Ed 89(2):F152–F155CrossRefPubMedPubMedCentralGoogle Scholar
  34. 34.
    Ohl C, Dornier L, Czajka C, Chobaut JC, Tavernier L (2009) Newborn hearing screening on infants at risk. Int J Pediatr Otorhinolaryngol 73(12):1691–1695. doi: 10.1016/j.ijporl.2009.08.027 CrossRefPubMedGoogle Scholar
  35. 35.
    Kraaijenga VJ, Smit AL, Stegeman I, Smilde JJ, van Zanten GA, Grolman W (2015) Factors that influence outcomes in cochlear implantation in adults, based on patient related characteristics—a retrospective study. Clin Otolaryngol. doi: 10.1111/coa.12571 Google Scholar
  36. 36.
    Kawashima H, Tsuji N (1987) Syndrome of microcephaly, deafness/malformed ears, mental retardation and peculiar facies in a mother and son. Clin Genet 31(5):303–307CrossRefPubMedGoogle Scholar
  37. 37.
    Brown CB, Ogg CS, Cameron JS, Bewick M (1974) High dose frusemide in acute reversible intrinsic renal failure. A preliminary communication. Scott Med J 19(Suppl 1):35–39PubMedGoogle Scholar
  38. 38.
    Mathog RH, Klein WJ Jr (1969) Ototoxicity of ethacrynic acid and aminoglycoside antibiotics in uremia. N Engl J Med 280(22):1223–1224. doi: 10.1056/NEJM196905292802208 CrossRefPubMedGoogle Scholar
  39. 39.
    Abbas L, Rivolta MN (2015) Aminoglycoside ototoxicity and hair cell ablation in the adult gerbil: a simple model to study hair cell loss and regeneration. Hear Res 325:12–26. doi: 10.1016/j.heares.2015.03.002 CrossRefPubMedPubMedCentralGoogle Scholar
  40. 40.
    Nadol JB Jr, Thornton AR (1987) Ultrastructural findings in a case of Meniere’s disease. Ann Otol Rhinol Laryngol 96(4):449–454CrossRefPubMedGoogle Scholar
  41. 41.
    Momin SR, Melki SJ, Alagramam KN, Megerian CA (2010) Spiral ganglion loss outpaces inner hair cell loss in endolymphatic hydrops. Laryngoscope 120(1):159–165. doi: 10.1002/lary.20673 PubMedGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Philipp Mittmann
    • 1
    Email author
  • I. Todt
    • 1
  • A. Ernst
    • 1
  • G. Rademacher
    • 2
  • S. Mutze
    • 2
  • S. Göricke
    • 3
  • M. Schlamann
    • 4
  • R. Ramalingam
    • 5
  • S. Lang
    • 6
  • F. Christov
    • 6
  • D. Arweiler-Harbeck
    • 6
  1. 1.Department of OtolaryngologyUnfallkrankenhaus Berlin (UKB)BerlinGermany
  2. 2.Department of RadiologyUKBBerlinGermany
  3. 3.Department of Neuroradiology and Radiology, University Hospital of EssenUniversity Duisburg-EssenEssenGermany
  4. 4.Department of Neuroradiology and RadiologyUniversity Hospital Giessen and Marburg GmbHMarburgGermany
  5. 5.KKR ENT Hospital and Research InstituteChennaiIndia
  6. 6.Department of Otolaryngology, Head and Neck Surgery, University Hospital of EssenUniversity Duisburg-EssenEssenGermany

Personalised recommendations