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Updated: Mar 23, 2026
In Vivo Morphometric Analysis of Human Cranial Nerves Using Magnetic Resonance Imaging in Menière's Disease Ears and Normal Hearing Ears
Published on: February 21, 2018
Malformation of the eighth cranial nerve in children
Carlos de Paula-Vernetta1, Noelia Muñoz-Fernández1, Fernando Mas-Estellés2
1Servicio de Otorrinolaringología, Hospital Universitario y Politécnico La Fe, Valencia, España.
Insights
Congenital sensorineural hearing loss in children can involve auditory nerve malformations. Magnetic resonance imaging (MRI) is the preferred diagnostic tool for detecting auditory nerve aplasia, crucial for understanding hearing loss.
Area of Science:
- Pediatric audiology
- Neuroscience
- Medical imaging
Background:
- Congenital sensorineural hearing loss (SNHL) affects 1.5-6 in 1,000 newborns.
- Auditory neuropathy accounts for 1-10% of SNHL cases, with vestibulocochlear nerve (VCN) aplasia being less common.
- Understanding VCN aplasia is crucial for diagnosing and managing SNHL in children.
Purpose of the Study:
- To describe clinical features, hearing thresholds, and etiology of SNHL in children with VCN aplasia.
- To evaluate the diagnostic performance of imaging techniques for VCN malformations.
- To correlate auditory nerve malformation types with hearing loss severity.
Main Methods:
- Retrospective analysis of 34 children with auditory nerve malformation and profound hearing loss.
- Evaluation of demographic data, hearing assessments, genetics, risk factors, and associated malformations using Casselman's and Sennaroglu's classifications.
- Statistical analysis of findings, including sensitivity and specificity of CT and MRI.
Main Results:
- Auditory nerve malformation was identified in 10% of children undergoing cochlear implant evaluation.
- Bilateral VCN aplasia (IIa/IIa, I/I) was common (58.8%), with a link to systemic pathology.
- Hearing loss severity correlated significantly with VCN aplasia types (Casselman's classification).
Conclusions:
- Auditory nerve aplasia/hypoplasia is a significant factor in pediatric SNHL, present in 10% of cochlear implant candidates.
- MRI is the most sensitive imaging modality for detecting auditory nerve malformations, surpassing CT scans.
- Accurate diagnosis of VCN malformations is essential for effective management of hearing loss.
Introduction And Objectives:
Prevalence of congenital sensorineural hearing loss (SNHL) is approximately 1.5-6 in every 1,000 newborns. Dysfunction of the auditory nerve (auditory neuropathy) may be involved in up to 1%-10% of cases; hearing losses because of vestibulocochlear nerve (VCN) aplasia are less frequent. The objectives of this study were to describe clinical manifestations, hearing thresholds and aetiology of children with SNHL and VCN aplasia.
Methodology:
We present 34 children (mean age 20 months) with auditory nerve malformation and profound HL taken from a sample of 385 children implanted in a 10-year period. We studied demographic characteristics, hearing, genetics, risk factors and associated malformations (Casselman's and Sennaroglu's classifications). Data were processed using a bivariate descriptive statistical analysis (P<.05).
Results:
Of all the cases, 58.8% were bilateral (IIa/IIa and I/I were the most common). Of the unilateral cases, IIb was the most frequent. Auditory screening showed a sensitivity of 77.4%. A relationship among bilateral cases and systemic pathology was observed. We found a statistically significant difference when comparing hearing loss impairment and patients with different types of aplasia as defined by Casselman's classification. Computed tomography (CT) scan yielded a sensitivity of 46.3% and a specificity of 85.7%. However, magnetic resonance imaging (MRI) was the most sensitive imaging test.
Conclusions:
Ten percent of the children in a cochlear implant study had aplasia or hypoplasia of the auditory nerve. The degree of auditory loss was directly related to the different types of aplasia (Casselman's classification) Although CT scan and MRI are complementary, the MRI is the test of choice for detecting auditory nerve malformation.
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