Abstract
Three methods of determining electrode insertion depth in cochlear implantees are studied: intraoperative counting of inserted electrodes, plain film radiography using Stenvers projection and postoperative electrode function testing. In 16 cases the number of electrodes inserted in the cochlea were counted both by the surgeon at surgery and by two independent observers on plain film radiographs using Stenvers projections. The electrode function was tested postoperatively. The differences between the three methods in estimation of the number of intracochlear electrodes were analyzed with t -tests, and 95% confidence intervals (95% CI) of the mean differences were calculated. The mean difference between the radiograph observers was 0.25 electrode (95% CI, –0.69 to 1.19 electrodes.) The mean difference between radiography observations and the surgical counts was 0.60 electrode (95% CI, –0.71 to 1.91 electrodes.) The mean difference between surgical counting and electrode function testing was 0.40 electrode (95% CI, –0.66 to 1.46 electrodes.) The mean difference between radiograph observations and electrode function testing was 0.50 electrode (95% CI, –0.51 to 1.51 electrodes.) No significant differences existed between the three methods. Our findings showed similar results in estimating electrode array insertion depth with the three methods. Plain film radiography using Stenvers projection is satisfactory if imaging is indicated for determining the number of inserted electrodes.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Applebaum EL, Valvassori GE (1990) Further studies on the effects of magnetic resonance imaging fields on middle ear implants. Ann Otol Rhinol Laryngol 99: 801–804
Bredberg G, Lindstrom B (1995) Insertion length of electrode array and its relation to speech communication performance and nonauditory side effects in multichannel-implanted patients. Ann Otol Rhinol Laryngol [Suppl] 166: 256–258
Chen JM, Farb R, Hanusaik L, Shipp D, Nedzelski JM (1999) Depth and quality of electrode insertion: a radiologic and pitch scaling assessment of two cochlear implant systems. Am J Otol 20: 192–197
Chou CK, McDougall JA, Can KW (1995) Absence of radiofrequency heating from auditory implants during magnetic resonance imaging. Bioelectromagnetics 16: 307–316
Czerny C, Steiner E, Gstoettner W, Baumgartner WD, Imhof H (1997) Postoperative radiographic assessment of the Combi 40 cochlear implant. AJR Am J Roentgenol 169: 1689–1694
Gstoettner W, Franz P, Hamzavi J, Plenk H Jr, Baumgartner W, Czerny C (1999) Intracochlear position of cochlear implant electrodes. Acta Otolaryngol 119: 229–233
Hartrampf R, Dahm MC, Battmer RD, Gnadeberg D, Strauss-Schier A, Rost U, Lenarz T (1995) Insertion depth of the Nucleus electrode array and relative performance. Ann Otol Rhinol Laryngol [Suppl] 166: 277–280
Himi T, Kataura A, Sakata M, Odawara Y, Satoh JI, Sawaishi M (1996) Three-dimensional imaging of the temporal bone using a helical CT scan and its application in patients with cochlear implantation. ORL J Otorhinolaryngol Relat Spec 58: 298–300
Ketten DR, Skinner MW, Wang G, Vannier MW, Gates GA, Neely JG (1998) In vivo measures of cochlear length and insertion depth of nucleus cochlear implant electrode arrays. Ann Otol Rhinol Laryngol [Suppl] 175: 1–16
Kumakawa K, Takeda H, Ujita N (1997) Determining the optimum insertion length of electrodes in the cochlear 22-channel implant: results of a clinical study. Adv Otorhinolaryngol 52: 129–134
Lawson JT, Cranley K, Toner JG (1998) Digital imaging: a valuable technique for the postoperative assessment of cochlear implantation. Eur Radiol 8: 951–954
Marsh MA, Xu J, Blamey PJ, Whitford LA, Xu SA, Silverman JM, Clark GM (1993) Radiologic evaluation of multichannel intracochlear implant insertion depth [published erratum appears in Am J Otol 1993 Nov 14: 627]. Am J Otol 14: 386–391
Mukherji SK, Mancuso AA, Kotzur IM, Slattery WH III, Swartz JD, Tart RP, Nall A (1994) CT of the temporal bone: findings after mastoidectomy, ossicular reconstruction, and cochlear implantation. AJR Am J Roentgenol 163: 1467–1471
Qaiyumi SA, Hendrickx P, Bachor E, Laszig R, Battmer BD, Galanski M (1991) Postoperative konventionelle Schläfenbeintomographie in der Beurteilung von reizinadäquaten Empfindungen (RIE) bei Cochlear-Implant-Patienten. Rofo Fortschr Geb Rontgenstr Neuen Bildgeb Verfahr 155: 442–444
Rosenberg RA, Cohen NL, Reede DL (1987) Radiographic imaging for the cochlear implant. Ann Otol Rhinol Laryngol 96: 300–304
Shpizner BA, Holliday RA, Roland JT, Cohen NL, Waltzman SB, Shapiro WH (1995) Postoperative imaging of the multichannel cochlear implant. AJNR Am J Neuroradiol 16: 1517–1524
Stenvers HW (1917) Roentgenology of os petrosum. Arch Radiol Elec 22: 97–112
Teissl C, Kremser C, Hochmair ES, Hochmair-Desoyer IJ (1999) Magnetic resonance imaging and cochlear implants: compatibility and safety aspects. J Magn Reson Imaging 9: 26–38
Weber BP, Goldring JE, Santogrossi T, Koestler H, Tziviskos G, Battmer R, Lenarz T (1998) Magnetic resonance imaging compatibility testing of the Clarion 1.2 cochlear implant. Am J Otol 19: 584–590
Youssefzadeh S, Baumgartner W, Dorffner R, Gstottner W, Trattnig S (1998) MR compatibility of Med EL cochlear implants: clinical testing at 1.0 T. J Comput Assist Tomogr 22: 346–350
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Bettman, R.H.R., van Olphen, A.F., Zonneveld, F.W. et al. Electrode insertion depth in cochlear implantees estimated during surgery, on plain film radiographs and with electrode function testing. Eur Arch Otorhinolaryngol 260, 536–540 (2003). https://doi.org/10.1007/s00405-003-0593-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00405-003-0593-z