Management of Cochlear Nerve Hypoplasia and Aplasia

2018 ◽  
pp. 81-92 ◽  
Author(s):  
Simon R. Freeman ◽  
Levent Sennaroglu
Keyword(s):  
Cochlear Nerve ◽  
Cochlear Nerve Hypoplasia

Unilateral cochlear nerve hypoplasia in children with mild to moderate hearing loss

2012 ◽  
Vol 132 (11) ◽  
pp. 1160-1167 ◽  
Author(s):  
Hidenobu Taiji ◽  
Noriko Morimoto ◽  
Tatsuo Matsunaga
Keyword(s):  
Hearing Loss ◽  
Cochlear Nerve ◽  
Cochlear Nerve Hypoplasia ◽  
Moderate Hearing Loss

Cochlear nerve anomalies in paediatric single-sided deafness – prevalence and implications for cochlear implantation strategies

2020 ◽  
pp. 1-4
Author(s):  
K Pollaers ◽  
A Thompson ◽  
J Kuthubutheen
Keyword(s):  
Magnetic Resonance Imaging ◽  
Hearing Loss ◽  
Magnetic Resonance ◽  
Sensorineural Hearing Loss ◽  
Cochlear Nerve ◽  
Sensorineural Hearing ◽  
Resonance Imaging ◽  
Bilateral Sensorineural Hearing Loss ◽  
Single Sided Deafness ◽  
Cochlear Nerve Hypoplasia

Abstract Objective To determine the prevalence of cochlear nerve anomalies on magnetic resonance imaging in patients with unilateral or bilateral sensorineural hearing loss. Methods A retrospective case series was conducted at a tertiary referral centre. The inclusion criteria were paediatric patients with bilateral or unilateral sensorineural hearing loss, investigated with magnetic resonance imaging. The primary outcome measure was the rate of cochlear nerve hypoplasia or aplasia. Results Of the 72 patients with unilateral sensorineural hearing loss, 39 per cent (28 cases) had absent or hypoplastic cochlear nerves on the affected side. Fifteen per cent (11 cases) had other abnormal findings on magnetic resonance imaging. Eighty-four patients had bilateral sensorineural hearing loss, of which cochlear nerve hypoplasia or aplasia was identified only in 5 per cent (four cases). Other abnormal findings were identified in 14 per cent (12 cases). Conclusion Paediatric patients with unilateral sensorineural hearing loss are more likely to have cochlear nerve anomalies than those patients with bilateral sensorineural hearing loss. This has important implications regarding cochlear implantation for patients with single-sided deafness.

Outcomes after cochlear implant provision in children with cochlear nerve hypoplasia or aplasia

2018 ◽  
Vol 112 ◽  
pp. 132-140 ◽  
Author(s):  
Désirée Ehrmann-Müller ◽  
Heike Kühn ◽  
Cordula Matthies ◽  
Rudolf Hagen ◽  
Wafaa Shehata-Dieler
Keyword(s):  
Cochlear Implant ◽  
Cochlear Nerve ◽  
Cochlear Nerve Hypoplasia

scholarly journals Cochlear nerve hypoplasia identified years after passing newborn hearing screen

2020 ◽  
Vol 17 ◽  
pp. 100221
Author(s):  
Ryan Tabtabai ◽  
Sam Schild ◽  
Daniel Ballard ◽  
Michal Preis
Keyword(s):  
Cochlear Nerve ◽  
Newborn Hearing ◽  
Cochlear Nerve Hypoplasia

Improved imaging of Cochlear nerve hypoplasia using a 3-tesla variable flip-angle turbo spin-echo sequence and a 7-cm surface coil

2013 ◽  
Vol 124 (3) ◽  
pp. 751-754 ◽  
Author(s):  
Anja M. Giesemann ◽  
Peter Raab ◽  
Stefan Lyutenski ◽  
Sabine Dettmer ◽  
Eva Bültmann ◽  
...  
Keyword(s):  
Spin Echo ◽  
Surface Coil ◽  
Flip Angle ◽  
Cochlear Nerve ◽  
3 Tesla ◽  
Variable Flip Angle ◽  
Turbo Spin Echo ◽  
Turbo Spin ◽  
Spin Echo Sequence ◽  
Cochlear Nerve Hypoplasia

scholarly journals Comparison of ABR and ASSR using narrow-band-chirp-stimuli in children with cochlear malformation and/or cochlear nerve hypoplasia suffering from severe/profound hearing loss

2021 ◽  
Author(s):  
Katharina Eder ◽  
Daniel Polterauer ◽  
Sebastian Semmelbauer ◽  
Maria Schuster ◽  
Tobias Rader ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Narrow Band ◽  
Hearing Threshold ◽  
Cochlear Nerve ◽  
Lower Percentage ◽  
Control Group ◽  
Threshold Estimation ◽  
Severe Hearing Loss ◽  
Cochlear Malformation ◽  
Cochlear Nerve Hypoplasia

Abstract Objectives In pediatric audiology, objective techniques for hearing threshold estimation in infants and children with profound or severe hearing loss play a key role. Auditory brainstem responses (ABR) and auditory steady-state responses (ASSR) are available for frequency-dependent hearing threshold estimations and both techniques show strong correlations but sometimes with considerable differences. The aim of the study was to compare hearing threshold estimations in children with and without cochlear and cochlear nerve malformations. Methods Two groups with profound or severe hearing loss were retrospectively compared. In 20 ears (15 children) with malformation of the inner ear and/or cochlear nerve hypoplasia and a control group of 20 ears (11 children) without malformation, ABR were measured with the Interacoustics Eclipse EP25 ABR system® (Denmark) with narrow-band CE-chirps® at 500, 1000, 2000 and 4000 Hz and compared to ASSR at the same center frequencies under similar conditions. Results ABR and ASSR correlated significantly in both groups (r = 0.413 in malformation group, r = 0.82 in control group). The malformation group showed a significantly lower percentage of “equal” hearing threshold estimations than the control group. In detail, patients with isolated cochlear malformation did not differ significantly from the control group, whereas patients with cochlear nerve hypoplasia showed significantly greater differences. Conclusion ABR and ASSR should be used jointly in the diagnostic approach in children with suspected profound or severe hearing loss. A great difference in hearing threshold estimation between these techniques could hint at the involvement of cochlear nerve or cochlear nerve hypoplasia itself.

Cochlear Nerve Hypoplasia: Audiological Characteristics in Children and Adults

2019 ◽  
Vol 24 (3) ◽  
pp. 147-153
Author(s):  
Betul Cicek Cinar ◽  
Emel Tahir ◽  
Merve Ozbal Batuk ◽  
Mehmet Yarali ◽  
Gonca Sennaroglu ◽  
...  
Keyword(s):  
Hearing Loss ◽  
General Term ◽  
Cochlear Nerve ◽  
Type I ◽  
Radiological Findings ◽  
Ear Malformations ◽  
Cochlear Nerve Aplasia ◽  
Incomplete Partition ◽  
Cochlear Malformation ◽  
Cochlear Nerve Hypoplasia

Background: Cochlear nerve deficiency is a general term used to describe both cochlear nerve hypoplasia (CNH) and cochlear nerve aplasia. Although these two conditions can have similar results on audiological evaluation, CNH yields more variation in audiological tests. Objectives: To describe the audiological characteristics of the CNH cases in our series in relation to radiological findings. Methods: We reviewed the medical charts, audiological findings, and radiological findings on cases with CNH. We included cases with CNH in one ear or both ears. Out of 90 subjects with CNH, we included a total of 40 individuals (21 women and 19 men; 49 ears) in the current study. We reviewed and analyzed the participants’ audiological test results according to the radiological findings. Results: Cases with CNH showed variations according to the cochlear structure. There were 13 normal cochleae, 4 with incomplete partition type I, and 32 with cochlear hypoplasia. The accompanying cochlear apertures also showed variation: 17 were normal, 28 stenotic, and 4 aplastic cochlear apertures. The subjects displayed hearing loss ranging from moderate to profound; furthermore, 4 subjects had no response to sound whatsoever. The degree of hearing loss was not statistically significantly different with regard to the presence or absence of cochlear malformation with CNH (p > 0.005). We observed both sensorineural hearing loss and mixed-type hearing loss among the CNH cases. Conclusions: CNH is the presence of a cochlear nerve that is smaller in diameter than the facial nerve. It can be accompanied with other associated inner ear malformations of different degrees of severity. We observed degrees of hearing loss ranging from moderate to profound.

Isolated Cochlear Nerve Hypoplasia with Various Internal Auditory Meatus Deformities in Children

2007 ◽  
Vol 116 (7) ◽  
pp. 520-524 ◽  
Author(s):  
Ken Ito ◽  
Shin-Ich Ishimoto ◽  
Shotaro Karino
Keyword(s):  
Inner Ear ◽  
Otoacoustic Emissions ◽  
Vestibular Nerve ◽  
Cochlear Nerve ◽  
Distortion Product Otoacoustic Emissions ◽  
Nerve Function ◽  
Speech Discrimination ◽  
Internal Auditory Meatus ◽  
Distortion Product ◽  
Cochlear Nerve Hypoplasia

Objectives: We report neuro-otological findings in isolated congenital cochlear nerve hypoplasia with various bony deformities and evaluate relationships between functional impairment and the radiologic dimensions of the internal auditory meatus (IAM). Methods: We performed imaging and functional analyses on consecutive juvenile or adolescent patients between 2001 and 2005 with “isolated” unilateral hypoplasia of the cochlear nerve, without inner ear anomaly or other deformities. Results: Among 20 patients with unilateral profound deafness who underwent imaging studies, 10 (50%) passed the inclusion criteria. In all affected ears, auditory brain stem responses were absent and the speech discrimination score was very poor (0% to 5%). Distortion product otoacoustic emissions were good in 2 ears, fair in 1 ear, and poor in 7 ears. Caloric responses were absent in 2 ears, reduced in 3 ears, and normal in 5 ears. Inferior vestibular nerve function and facial nerve function were normal in all ears. Distortion product otoacoustic emissions and caloric responses tended to be better in ears with less severe narrowing of the IAM. Conclusions: The risk of co-involvement of the inner ear and superior vestibular nerve functions is higher in the presence of a narrower bony IAM. Cochlear nerve hypoplasia is proposed as one of the most important causes of juvenile unilateral deafness because of its unexpectedly high incidence.

Developing Intraoperative Cochlear Nerve Monitoring during Vestibular Schwannoma Surgery

2012 ◽  
Vol 73 (S 02) ◽  
Author(s):  
A. Kasbekar ◽  
Y. Tam ◽  
R. Carlyon ◽  
J. Deeks ◽  
N. Donnelly ◽  
...  
Keyword(s):  
Vestibular Schwannoma ◽  
Cochlear Nerve ◽  
Nerve Monitoring
Sign in / Sign up

Export Citation Format

Share Document