Variations in Cochlear Size of Cochlear Implant Candidates

Devira Zahara; Rima Diana Dewi; Askaroellah Aboet; Fikri Mirza Putranto; Netty Delvrita Lubis; Taufik Ashar

doi:10.1055/s-0038-1661360

International Archives of Otorhinolaryngology, Table of Contents

CC BY-NC-ND 4.0 · Int Arch Otorhinolaryngol 2019; 23(02): 184-190
DOI: 10.1055/s-0038-1661360

Original Research

Thieme Revinter Publicações Ltda Rio de Janeiro, Brazil

Variations in Cochlear Size of Cochlear Implant Candidates

Devira Zahara

¹Department of Otorhinolaryngology - Head and Neck Surgery, Faculty of Medicine, Universitas Sumatera Utara, Medan, Sumatera Utara, Indonesia

,

Rima Diana Dewi

¹Department of Otorhinolaryngology - Head and Neck Surgery, Faculty of Medicine, Universitas Sumatera Utara, Medan, Sumatera Utara, Indonesia

,

Askaroellah Aboet

¹Department of Otorhinolaryngology - Head and Neck Surgery, Faculty of Medicine, Universitas Sumatera Utara, Medan, Sumatera Utara, Indonesia

,

Fikri Mirza Putranto

²Department of Otorhinolaryngology - Head and Neck Surgery, Faculty of Medicine, and Health Sciences, Universitas Islam Negeri Syarif Hidayatullah Jakarta, Jakarta, Indonesia

,

Netty Delvrita Lubis

³Department of Radiology, Faculty of Medicine, Universitas Sumatera Utara, Medan, Sumatera Utara, Indonesia

,

Taufik Ashar

⁴Department of Environmental Health, Faculty of Public Health, Universitas Sumatera Utara, Medan, Sumatera Utara, Indonesia

› Author Affiliations

Abstract

Introduction The cochlear anatomy varies in each individual, and that has an impact on decisions regarding the insertion of electrodes. The measurement of the cochlear size is the routine examination required to choose the proper cochlear implant (CI) electrodes.

Objective To acquire normative data on the size of the cochlea (length, width, height, scala timpani [ST] height, cochlear duct length [CDL]) of CI candidates in Medan, Indonesia.

Methods This descriptive study was conducted based on high-resolution computed tomography (HRCT) temporal bone data and on HRCT temporal data manipulated to reconstruct three-dimensional (3D) multiplanar images with OsiriX MD DICOM Viewer version 9.5.1 (Pixmeo SARL, Bernex, Geneva, Switzerland) viewer of 18 patients (36 ears) who were CI candidates in Medan, Indonesia, in order to determine cochlear length (A), cochlear width, cochlear height, ST height and CDL, calculated through a simple mathematical function.

Results The average cochlear length (A) was 8.75 mm (standard deviation [SD] = 0.31 mm); the average cochlear width was 6.53 mm (SD = 0.35 mm); the average cochlear height was 3.26 mm (SD = 0.24 mm) and the average ST height at the basal cochlea was 1.00 mm (SD = 0.1 mm); and 0.71 mm (SD = 0.1 mm) at the half turn of cochlea. The average total CDL was 32.45 mm (SD = 1.31 mm; range: 30.01–34.83 mm).

Conclusion The cochlear size varies in each individual; therefore, the temporal bone measurement of CI candidates using HRCT is essential: for the selection of suitable implant electrodes; to minimize cochlear damages at the insertion of the electrode arrays; and to maximize the hearing improvements.

Keywords

cochlea - cochlear implant - computed tomography - temporal bone

Full Text

References

References
1 Chi DH, Sabo DL. Pediatric audiology and implantable hearing devices. In: Johnson JT, Rosen CA. , eds. Bailey's Head and Neck Surgery Otolaryngology. 5th ed. Philadelphia: Lippincott Williams & Wilkins, a Wolters Kluwer business; 2014: 1507-1522
2 Vincenti V, Bacciu A, Guida M. , et al. Pediatric cochlear implantation: an update. Ital J Pediatr 2014; 40 (01) 72
3 Paludetti G, Conti G, DI Nardo W. , et al. Infant hearing loss: from diagnosis to therapy Official Report of XXI Conference of Italian Society of Pediatric Otorhinolaryngology. Acta Otorhinolaryngol Ital 2012; 32 (06) 347-370
4 Xu J, Xu SA, Cohen LT, Clark GM. Cochlear view: postoperative radiography for cochlear implantation. Am J Otol 2000; 21 (01) 49-56
5 Dimopoulos P, Muren C. Anatomic variations of the cochlea and relations to other temporal bone structures. Acta Radiol 1990; 31 (05) 439-444
6 Erixon E, Högstorp H, Wadin K, Rask-Andersen H. Variational anatomy of the human cochlea: implications for cochlear implantation. Otol Neurotol 2009; 30 (01) 14-22
7 Erixon E, Liu W, Rask-Andersen H. Anatomic studies of the human cochlea: implications for cochlear implantation. The Registry 2011; 19 (01) 1-7
8 Avci E, Nauwelaers T, Lenarz T, Hamacher V, Kral A. Variations in microanatomy of the human cochlea. J Comp Neurol 2014; 522 (14) 3245-3261
9 Wysocki J. Dimensions of the human vestibular and tympanic scalae. Hear Res 1999; 135 (1-2): 39-46
10 Biedron S, Prescher A, Ilgner J, Westhofen M. The internal dimensions of the cochlear scalae with special reference to cochlear electrode insertion trauma. Otol Neurotol 2010; 31 (05) 731-737
11 Escudé B, James C, Deguine O, Cochard N, Eter E, Fraysse B. The size of the cochlea and predictions of insertion depth angles for cochlear implant electrodes. Audiol Neurootol 2006; ; 11 (01) , Suppl (Suppl. 01) 27-33
12 Hardy M. The length of the organ of Corti in man. Am J Anat 1938; 62 (02) 291-311
13 Rask-Andersen H, Erixon E, Kinnefors A, Löwenheim H, Schrott-Fischer A, Liu W. Anatomy of the human cochlea--implications for cochlear implantation. Cochlear Implants Int 2011; 12 (Suppl (Suppl. 01) S8-S13
14 Shin KJ, Lee JY, Kim JN. , et al. Quantitative analysis of the cochlea using three-dimensional reconstruction based on microcomputed tomographic images. Anat Rec (Hoboken) 2013; 296 (07) 1083-1088
15 Verbist BM, Ferrarini L, Briaire JJ. , et al. Anatomic considerations of cochlear morphology and its implications for insertion trauma in cochlear implant surgery. Otol Neurotol 2009; 30 (04) 471-477
16 Kawano A, Seldon HL, Clark GM. Computer-aided three-dimensional reconstruction in human cochlear maps: measurement of the lengths of organ of Corti, outer wall, inner wall, and Rosenthal's canal. Ann Otol Rhinol Laryngol 1996; 105 (09) 701-709
17 Ketten DR, Skinner MW, Wang G, Vannier MW, Gates GA, Neely JG. In vivo measures of cochlear length and insertion depth of nucleus cochlear implant electrode arrays. Ann Otol Rhinol Laryngol Suppl 1998; 175: 1-16
18 Kisser U, Ertl-Wagner B, Hempel JM. , et al. High-resolution computed tomography-based length assessments of the cochlea--an accuracy evaluation. Acta Otolaryngol 2014; 134 (10) 1011-1015
19 Thong JF, Low D, Tham A, Liew C, Tan TY, Yuen HW. Cochlear duct length-one size fits all?. Am J Otolaryngol 2017; 38 (02) 218-221
20 Aschendorff A. Imaging in cochlear implant patients. GMS Curr Top Otorhinolaryngol Head Neck Surg 2011; 10: Doc07
21 Pelliccia P, Venail F, Bonafé A. , et al. Cochlea size variability and implications in clinical practice. Acta Otorhinolaryngol Ital 2014; 34 (01) 42-49
22 Koch RW, Ladak HM, Elfarnawany M, Agrawal SK. Measuring Cochlear Duct Length - a historical analysis of methods and results. J Otolaryngol Head Neck Surg 2017; 46 (01) 19
23 Teissier N, Van Den Abbeele T, Sebag G, Elmaleh-Berges M. Computed Tomography measurements of the normal and the pathologic cochlea in children. Pediatr Radiol 2010; 40 (03) 275-283
24 Gnansia D, Demarcy T, Vandersteen C. , et al. Optimal electrode diameter in relation to volume of the cochlea. Eur Ann Otorhinolaryngol Head Neck Dis 2016; ; 133 (01) , Suppl (Suppl. 01) S66-S67
25 Wimmer W, Gerber N, Dhanasingh A. , et al. In-vitro microCT validation of preoperative cochlear duct length estimation. CURAC 2013; 1477: 143-146
26 Johnston JD, Scoffings D, Chung M. , et al. Computed tomography estimation of cochlear duct length can predict full insertion in cochlear implantation. Otol Neurotol 2016; 37 (03) 223-228
27 Baskent D, Shannon RV. Speech recognition under conditions of frequency-place compression and expansion. J Acoust Soc Am 2003; 113 (4 Pt 1): 2064-2076
28 Skinner MW, Ketten DR, Holden LK. , et al. CT-derived estimation of cochlear morphology and electrode array position in relation to word recognition in Nucleus-22 recipients. J Assoc Res Otolaryngol 2002; 3 (03) 332-350
29 James C, Albegger K, Battmer R. , et al. Preservation of residual hearing with cochlear implantation: how and why. Acta Otolaryngol 2005; 125 (05) 481-491
30 Adunka O, Unkelbach MH, Mack MG, Radeloff A, Gstoettner W. Predicting basal cochlear length for electric-acoustic stimulation. Arch Otolaryngol Head Neck Surg 2005; 131 (06) 488-492
31 Gao Z, Tian X, Feng G. Cochlea duct length of Chinese adults for individualized cochlear electrode design. Meeting Abstract. 84 ^th Annual Meeting of the German Society of Oto-Rhino-Laryngology Head and Neck Surgery. Numberg: German Medical Science GMS; 2013
32 Grover M, Mishra P, Gupta G, Jangid M. Cochlear duct length: are we giving it adequate importance?. Otolaryngol Head Neck Surg 2013; 149 (02) 219-225
33 Hassan LA, Ayad CE, Hassan HA, Abdalla EA, Mohamed ME. Normative Sudanese cochlea measurements using high resolution computerized tomography. GARJMMS 2014; 3 (06) 117-123
34 Alexiades G, Dhanasingh A, Jolly C. Method to estimate the complete and two-turn cochlear duct length. Otol Neurotol 2015; 36 (05) 904-907
35 Purcell D, Johnson J, Fischbein N, Lalwani AK. Establishment of normative cochlear and vestibular measurements to aid in the diagnosis of inner ear malformations. Otolaryngol Head Neck Surg 2003; 128 (01) 78-87
36 Tarabishi MN, Sarwat AA, Rabie HM. , et al. Miniature cochlea: a study of radiological measurements and its implications during the cochlear implant surgery. Egypt J Otolaryngol 2016; 32 (03) 170-177
37 Braun K, Böhnke F, Stark T. Three-dimensional representation of the human cochlea using micro-computed tomography data: presenting an anatomical model for further numerical calculations. Acta Otolaryngol 2012; 132 (06) 603-613
38 Deep NL, Howard BE, Holbert SO, Hoxworth JM, Barrs DM. Measurement of cochlear length using the ‘A’ value for cochlea basal diameter: A feasibility study. Cochlear Implants Int 2017; 18 (04) 226-229
39 Lee J, Nadol Jr JB, Eddington DK. Depth of electrode insertion and postoperative performance in humans with cochlear implants: a histopathologic study. Audiol Neurootol 2010; 15 (05) 323-331
40 Hochmair I, Arnold W, Nopp P, Jolly C, Müller J, Roland P. Deep electrode insertion in cochlear implants: apical morphology, electrodes and speech perception results. Acta Otolaryngol 2003; 123 (05) 612-617
41 Hamzavi J, Arnoldner C. Effect of deep insertion of the cochlear implant electrode array on pitch estimation and speech perception. Acta Otolaryngol 2006; 126 (11) 1182-1187
42 Landwehr M, Fürstenberg D, Walger M, von Wedel H, Meister H. Effects of various electrode configurations on music perception, intonation and speaker gender identification. Cochlear Implants Int 2014; 15 (01) 27-35
43 Angeli SI, Goncalves S. Predicting depth of electrode insertion by cochlear measurements on computed tomography scans. Laryngoscope 2016; 126 (07) 1656-1661