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Bony cochlear nerve canal and internal auditory canal measures predict cochlear nerve status

Published online by Cambridge University Press:  01 June 2017

E Tahir ,
M D Bajin ,
G Atay ,
B Ö Mocan  and
L Sennaroğlu
E Tahir*
Affiliation:
Department of Otolaryngology – Head and Neck Surgery, Hacettepe University, Ankara, Turkey
M D Bajin
Affiliation:
Department of Otolaryngology – Head and Neck Surgery, Hacettepe University, Ankara, Turkey
G Atay
Affiliation:
Department of Otolaryngology – Head and Neck Surgery, Hacettepe University, Ankara, Turkey
B Ö Mocan
Affiliation:
Department of Radiology, Hacettepe University, Ankara, Turkey
L Sennaroğlu
Affiliation:
Department of Otolaryngology – Head and Neck Surgery, Hacettepe University, Ankara, Turkey
*
Address for correspondence: Dr E Tahir, Department of Otorhinolaryngology – Head and Neck Surgery, School of Medicine, Hacettepe University, Sıhhiye, Ankara 06100, Turkey Fax: +90 312 311 3500 E-mail: emeltahir@hotmail.com
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Abstract

Objectives:

The bony cochlear nerve canal is the space between the fundus of the internal auditory canal and the base of the cochlear modiolus that carries cochlear nerve fibres. This study aimed to determine the distribution of bony labyrinth anomalies and cochlear nerve anomalies in patients with bony cochlear nerve canal and internal auditory canal atresia and stenosis, and then to compare the diameter of the bony cochlear nerve canal and internal auditory canal with cochlear nerve status.

Methods:

The study included 38 sensorineural hearing loss patients (59 ears) in whom the bony cochlear nerve canal diameter at the mid-modiolus was 1.5 mm or less. Atretic and stenotic bony cochlear nerve canals were examined separately, and internal auditory canals with a mid-point diameter of less than 2 mm were considered stenotic. Temporal bone computed tomography and magnetic resonance imaging scans were reviewed to determine cochlear nerve status.

Results:

Cochlear hypoplasia was noted in 44 out of 59 ears (75 per cent) with a bony cochlear nerve canal diameter at the mid-modiolus of 1.5 mm or less. Approximately 33 per cent of ears with bony cochlear nerve canal stenosis also had a stenotic internal auditory canal and 84 per cent had a hypoplastic or aplastic cochlear nerve. All patients with bony cochlear nerve canal atresia had cochlear nerve deficiency. The cochlear nerve was hypoplastic or aplastic when the diameter of the bony cochlear nerve canal was less than 1.5 mm and the diameter of the internal auditory canal was less than 2 mm.

Conclusion:

The cochlear nerve may be aplastic or hypoplastic even if temporal bone computed tomography findings indicate a normal cochlea. If possible, patients scheduled to receive a cochlear implant should undergo both computed tomography and magnetic resonance imaging of the temporal bone. The bony cochlear nerve canal and internal auditory canal are complementary structures, and both should be assessed to determine cochlear nerve status.

Keywords

CochleaCochlear NerveTomography, X-Ray ComputedHearing Loss, SensorineuralEar, Inner
Type
Main Articles
Information
The Journal of Laryngology & Otology , Volume 131 , Issue 8 , August 2017 , pp. 676 - 683
Copyright
Copyright © JLO (1984) Limited 2017 

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References

1 Jackler, RK, Luxford, WM, House, WF. Congenital malformations of the inner ear: a classification based on embryogenesis. Laryngoscope 1987;97:2–14 Google Scholar
2 Miyasaka, M, Nosaka, S, Morimoto, N, Taiji, H, Masaki, H. CT and MR imaging for pediatric cochlear implantation: emphasis on the relationship between the cochlear nerve canal and the cochlear nerve. Pediatr Radiol 2010;40:1509–16Google Scholar
3 Fatterpekar, GM, Mukherji, SK, Alley, J, Lin, Y, Castillo, M. Hypoplasia of the bony canal for the cochlear nerve in patients with congenital sensorineural hearing loss: initial observations. Radiology 2000;215:243–6CrossRefGoogle ScholarPubMed
4 Stjernholm, C, Muren, C. Dimensions of the cochlear nerve canal: a radioanatomic investigation. Acta Otolaryngol 2002;122:43–8Google Scholar
5 Valvassori, G, Palacios, E. Internal auditory canal. Ear Nose Throat J 1998;77:173–8Google Scholar
6 Sennaroğlu, L. Cochlear implantation in inner ear malformations: a review article. Cochlear Implants Int 2010;11:4–41 CrossRefGoogle ScholarPubMed
7 Masuda, S, Usui, S, Matsunaga, T. High prevalence of inner-ear and/or internal auditory canal malformations in children with unilateral sensorineural hearing loss. Int J Pediatr Otorhinolaryngol 2013;77:228–32CrossRefGoogle ScholarPubMed
8 Valvassori, GE, Palacios, E. Magnetic resonance imaging of the internal auditory canal. Top Magn Reson Imaging 2000;11:52–65 Google Scholar
9 Sakina, MS, Goh, BS, Abdullah, A, Zulfiqar, MA, Saim, L. Internal auditory canal stenosis in congenital sensorineural hearing loss. Int J Pediatr Otorhinolaryngol 2006;70:2093–7Google Scholar
10 Adunka, OF, Roush, PA, Teagle, HF, Brown, CJ, Zdanski, CJ, Jewells, V et al. Internal auditory canal morphology in children with cochlear nerve deficiency. Otol Neurotol 2006;27:793–801 Google Scholar
11 Henderson, E, Wilkins, A, Huang, L, Kenna, M, Gopen, Q. Histopathologic investigation of the dimensions of the cochlear nerve canal in normal temporal bones. Int J Pediatr Otorhinolaryngol 2011;75:464–7Google Scholar
12 Yi, JS, Lim, HW, Kang, BC, Park, SY, Park, HJ, Lee, KS. Proportion of bony cochlear nerve canal anomalies in unilateral sensorineural hearing loss in children. Int J Pediatr Otorhinolaryngol 2013;77:530–3Google Scholar
13 Malgrange, B, Belachew, S, Thiry, M, Nguyen, L, Rogister, B, Alvarez, ML et al. Proliferative generation of mammalian auditory hair cells in culture. Mech Dev 2002;112:79–88 Google Scholar
14 Sennaroğlu, L, Ozkan, HB, Aslan, F. Impact of cochleovestibular malformations in treating children with hearing loss. Audiol Neurootol 2013;18:3–31 Google Scholar
15 Vaid, S, Vaid, N. Imaging for cochlear implantation: structuring a clinically relevant report. Clin Radiol 2014;69:9–24 CrossRefGoogle ScholarPubMed
16 Buchman, CA, Roush, PA, Teagle, HF, Brown, CJ, Zdanski, CJ. Auditory neuropathy characteristics in children with cochlear nerve deficiency. Ear Hear 2006;27:399–408 CrossRefGoogle ScholarPubMed
17 Kaga, K. Auditory nerve disease and auditory neuropathy spectrum disorders. Auris Nasus Larynx 2015;43:10–20 Google Scholar
18 Papsin, BC. Cochlear implantation in children with anomalous cochleovestibular anatomy. Laryngoscope 2005;115:1–26 Google Scholar
19 Sennaroğlu, L, Ziyal, I, Atas, A. Preliminary results of auditory brainstem implantation in prelingually deaf children with inner ear malformations including severe stenosis of the cochlear aperture and aplasia of the cochlear nerve. Otol Neurotol 2009;30:708–15Google Scholar
20 Colletti, L. Beneficial auditory and cognitive effects of auditory brainstem implantation in children. Acta Otolaryngol 2007;127:943–6Google Scholar
21 Colletti, L, Shannon, RV, Colletti, V. The development of auditory perception in children after auditory brainstem implantation. Audiol Neurootol 2014;19:386–94CrossRefGoogle ScholarPubMed