Cochlear Nerve Canal Stenosis: Association With MYH14 and MYH9 Genes

The bony cochlear nerve canal transmits the cochlear nerve as it passes from the fundus of the internal auditory canal to the cochlea. Stenosis of the cochlear nerve canal, defined as a diameter less than 1.0 mm in transverse diameter, is associated with inner ear anomalies and severe to profound congenital hearing loss. We describe an 11-month-old infant with nonsyndromic congenital sensorineural hearing loss with cochlear nerve canal stenosis. Next-generation sequencing revealed heterozygous mutations in MYH9 and MYH14, encoding for the inner ear proteins myosin heavy chain IIA and IIC. The patient’s hearing was rehabilitated with bilateral cochlear implantation.

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Molecular diagnostics for congenital hearing loss including 15 deafness genes using a next generation sequencing platform

BMC Medical Genomics ◽

10.1186/1755-8794-5-17 ◽

2012 ◽

Vol 5 (1) ◽

Cited By ~ 41

Author(s):

Sarah De Keulenaer ◽

Jan Hellemans ◽

Steve Lefever ◽

Jean-Pierre Renard ◽

Joachim De Schrijver ◽

...

Keyword(s):

Hearing Loss ◽

Next Generation Sequencing ◽

Molecular Diagnostics ◽

Congenital Hearing Loss ◽

Next Generation ◽

Sequencing Platform ◽

Next Generation Sequencing Platform ◽

Generation Sequencing

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Magnetic resonance imaging versus computed tomography in pre-operative evaluation of cochlear implant candidates with congenital hearing loss

The Journal of Laryngology & Otology ◽

10.1258/00222150260293619 ◽

2002 ◽

Vol 116 (10) ◽

pp. 804-810 ◽

Cited By ~ 37

Author(s):

Levent Sennaroglu ◽

Isil Saatci ◽

Ayse Aralasmak ◽

Bulent Gursel ◽

Ergin Turan

Keyword(s):

Magnetic Resonance Imaging ◽

Hearing Loss ◽

Magnetic Resonance ◽

Cochlear Implant ◽

Sensorineural Hearing Loss ◽

Internal Auditory Canal ◽

Cochlear Nerve ◽

Sensorineural Hearing ◽

Congenital Hearing Loss ◽

Resonance Imaging

Recent reports indicate that the cochlear nerve may be absent in some cases of congenital sensorineural hearing loss. The aim of this prospective study was to determine the incidence of cochlear nerve anomaly in cochlear implant candidates with congenital hearing loss using magnetic resonance imaging (MRI). Twenty-seven patients with congenital profound bilateral sensorineural hearing loss who were being evaluated for the cochlear implant procedure were studied.These patients had high-resolution computerized tomography (CT), through the petrous bone in axial sections. MRI examinations consisted of T1 and turbo spin echo (TSE) T2-weighted 3 mm axial images, and additional 3D Fourier Transform T2-weighted TSE sequences obtained on three different planes (axial, perpendicular and parallel to the internal auditory canal (IAC) i.e. oblique sagittal and coronal, respectively) for the purpose of cochlear nerve demonstration. Results showed that all of the 14 patients with normal CT of the temporal bone, had four distinct nerves in the distal part of the IAC on TSE-MRI. Thirteen patients demonstrated various bony malformations of the cochleovestibular system on CT. MRI revealed the absence of the cochleovestibular nerve in four patients where the IAC was very narrow or completely absent on CT. One patient with severe Mondini malformation who had an enlarged IAC demonstrated an isolated absent cochlear nerve.

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Correlation of cochlear aperture stenosis with cochlear nerve deficiency in congenital unilateral hearing loss and prognostic relevance for cochlear implantation

Scientific Reports ◽

10.1038/s41598-021-82818-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Eva Orzan ◽

Giulia Pizzamiglio ◽

Massimo Gregori ◽

Raffaella Marchi ◽

Lucio Torelli ◽

...

Keyword(s):

Decision Making ◽

Hearing Loss ◽

Inner Ear ◽

Cochlear Implantation ◽

Internal Auditory Canal ◽

Cochlear Nerve ◽

Depth Analysis ◽

Diagnostic Work ◽

Work Up ◽

Diagnostic Work Up

AbstractThe use of neonatal hearing screening has enabled the identification of congenital unilateral sensorineural hearing loss (USNHL) immediately after birth, and today there are several intervention options available to minimize potential adverse effects of this disease, including cochlear implantation. This study aims to analyze the characteristics of the inner ear of a homogeneous group of congenital non-syndromic USNHL to highlight the features of the inner ear, which can help in clinical, surgical, and rehabilitative decision-making. A retrospective chart review was carried out at a tertiary referral center. Systematic diagnostic work-up and rigorous inclusion–exclusion criteria were applied to 126 children with unilateral hearing impairment, leading to a selection of 39 strictly congenital and non-syndromic USNHL cases, undergoing computed tomography (CT) and magnetic resonance (MR) imaging studies. The frequency and type of malformations of the inner ear in USNHL and unaffected contralateral ears were assessed, with an in-depth analysis of the deficiency of the cochlear nerve (CND), the internal auditory canal (IAC) and the cochlear aperture (CA). Inner ear anomalies were found in 18 out of 39 (46%) of the USNHL patients. In 1 subject, the anomalies were bilateral, and the CND resulted in the predominant identified defect (78% of our abnormal case series), frequently associated with CA stenosis. Only 3 out of 14 children with CND presented stenosis of the IAC. CND and CA stenosis (and to a much lesser extent IAC stenosis) are a frequent association within congenital and non-syndromic USNHL that could represent a distinct pathological entity affecting otherwise healthy infants. In the context of a diagnostic work-up, the evaluation with CT and MRI measurements should take place in a shared decision-making setting with thorough counseling. Both imaging techniques have proven useful in differentiating the cases that will most likely benefit from the cochlear implant, from those with potentially poor implant performance.

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Anatomical and Pathological Findings of Magnetic Resonance Imaging in Idiopathic Sudden Sensorineural Hearing Loss

Journal of Audiology & Otology ◽

10.7874/jao.2020.00157 ◽

2020 ◽

Vol 24 (4) ◽

pp. 198-203

Author(s):

Min Bum Kim ◽

Jihyun Lim ◽

Il Joon Moon

Keyword(s):

Magnetic Resonance Imaging ◽

Hearing Loss ◽

Magnetic Resonance ◽

Sensorineural Hearing Loss ◽

Inner Ear ◽

Internal Auditory Canal ◽

Sudden Sensorineural Hearing Loss ◽

Cochlear Nerve ◽

Sensorineural Hearing ◽

Resonance Imaging

Background and Objectives: We sought to evaluate the diagnostic and prognostic value of measurable parameters of internal auditory canal (IAC) magnetic resonance imaging (MRI) in patients with idiopathic sudden sensorineural hearing loss (ISSNHL).Subjects and Methods: We retrospectively reviewed the patients with ISSNHL who underwent IAC MRI from January 2008 to March 2019. Measurable parameters of IAC MRI, such as the diameter of the IAC, bony cochlear nerve canal, and cross-sectional area of the cochlear nerve, were measured by a single examiner. These parameters were then compared between the affected and healthy sides. Inner-ear abnormalities such as intralabyrinthine hemorrhage or labyrinthitis were also evaluated. The relationship between the surveyed parameters and the diagnosis of ISSNHL was assessed.Results: A total of 208 patients with ISSNHL were included. The measured parameters of IAC MRI were not different between the affected and healthy sides and were also not associated with the diagnosis of ISSNHL. However, inner-ear abnormalities of IAC MRI in ISSNHL displayed a significant association with worse hearing before and after treatment. An age that was older than 40 years also correlated with poorer outcomes. Further, inner-ear abnormalities were more frequently detected when IAC MRI was performed early after ISSNHL onset.Conclusions: Patients with ISSNHL and inner ear abnormalities such as intralabyrinthine hemorrhage or labyrinthitis identified via IAC MRI may experience poorer hearing outcomes. To detect such abnormal findings, it is recommended to perform IAC MRI early after the onset of ISSNHL.

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Role of Computed Tomography and Magnetic Resonance Imaging in detecting the Prevalence of inner ear anomalies among cochlear implant candidates

QJM ◽

10.1093/qjmed/hcab106.007 ◽

2021 ◽

Vol 114 (Supplement_1) ◽

Author(s):

Alaa Nasser Hussain Zaher ◽

Tougan Taha Abd El Aziz ◽

Ahmed Samy Abdelrahman

Keyword(s):

Magnetic Resonance Imaging ◽

Computed Tomography ◽

Hearing Loss ◽

Cochlear Implant ◽

Inner Ear ◽

Resonance Imaging ◽

High Resolution Computed Tomography ◽

Vestibular Aqueduct ◽

Incomplete Partition ◽

Ear Anomalies

Abstract Background Hearing loss management using cochlear implants in patients with inner ear anomalies has long been discussed in the otology community. Magnetic resonances imaging (B,/IRI) and Computed tomography (CT) play important roles in the preoperative assessment of inner ear abnormalities such as cochlear nerve deficiency and variant anatomy as these abnormalities may not only affect the decision of the implantation procedure or the patient's prognosis regarding auditory improvement, but also the risk of complications. Objective To examine the prevalence of inner ear anomalies among cochlear implant recipients in patients with congenital sensorineural hearing loss among the pediatric age group in the Demerdash hospital, Ain Shams university using High resolution computed tomography (HRCT) and MRI imaging. Methods A retrospective descriptive study over the course of 9 months that included all patients that are candidates for cochlear implant referred to the Radiology department, Ain Shams University Hospitals for a preoperative imaging in the form of CT and VIRI scans. Results CT and MRI scans of 33 patients who had congenital hearing loss and were candidates for cochlear implantation with total 66 ears were reviewed. Inner ear anomalies were identified in 8 patients representing a prevalence (24.2%) with 14 ear diseased. Anomalies were seen bilaterally in 6 patients and unilaterally in 2 patients. Among the 14 diseased ear, 9 ears (64.3%) were seen with incomplete partition Il, 7 ears (50%) were seen with enlarged vestibular aqueduct, 4 ears (28.6%) were seen with cochlear hypoplasia, 3 ears (21.4%) were seen with semicircular canal aplasia, 2 ears (14.3%) were seen with incomplete partition type I, 2 ears (14.3%) were seen with cochlear nerve aplasia, 2 ears with cochlear aplasia (14.3%), I ear (7.1%) was seen with common cavity ear (7.1%) with complete labyrinthine aplasia. Conclusion Prevalence of inner ear anomalies among cochlear implant candidates was 24.2%. This result is consistent with results worldwide and the most common anomalies were Incomplete partition Il and large vestibular aqueduct. Abbreviations Computed tomography (CT), Magnetic resonance imaging (MRI), High resolution computed tomography (HRCT), Internal auditory canal (IAC), Cerebellopontine angle (CPA).

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Diverse spectrum of rare deafness genes underlies early-childhood hearing loss in Japanese patients: a cross-sectional, multi-center next-generation sequencing study

Orphanet Journal of Rare Diseases ◽

10.1186/1750-1172-8-172 ◽

2013 ◽

Vol 8 (1) ◽

pp. 172 ◽

Cited By ~ 57

Author(s):

Hideki Mutai ◽

Naohiro Suzuki ◽

Atsushi Shimizu ◽

Chiharu Torii ◽

Kazunori Namba ◽

...

Keyword(s):

Early Childhood ◽

Hearing Loss ◽

Next Generation Sequencing ◽

Japanese Patients ◽

Next Generation ◽

Cross Sectional ◽

Generation Sequencing ◽

Childhood Hearing Loss

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

The Journal of Laryngology & Otology ◽

10.1017/s0022215117001141 ◽

2017 ◽

Vol 131 (8) ◽

pp. 676-683 ◽

Cited By ~ 11

Author(s):

E Tahir ◽

M D Bajin ◽

G Atay ◽

B Ö Mocan ◽

L Sennaroğlu

Keyword(s):

Magnetic Resonance Imaging ◽

Computed Tomography ◽

Magnetic Resonance ◽

Temporal Bone ◽

Internal Auditory Canal ◽

Cochlear Nerve ◽

Resonance Imaging ◽

Canal Stenosis ◽

Canal Diameter ◽

Canal Atresia

AbstractObjectives: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.

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