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Published on: May 10, 2019
Auditory neuropathy characteristics in children with cochlear nerve deficiency
Craig A Buchman1, Patricia A Roush, Holly F B Teagle
1Department of Otolaryngology-Head and Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA. buchman@med.unc.edu
Ear and Hearing
|July 11, 2006
Summary
Cochlear nerve deficiency is a common cause of auditory neuropathy (AN) in children, often presenting after newborn hearing screening failures. Diagnosis requires MRI, as auditory brain stem response testing shows absent neural activity with cochlear microphonics.
Area of Science:
- Pediatric audiology
- Neuroscience
- Medical imaging
Background:
- Auditory neuropathy (AN) is characterized by abnormal auditory brain stem response (ABR) testing.
- Cochlear nerve deficiency, including absent or small cochlear nerves, is an underrecognized cause of AN.
Purpose of the Study:
- To describe the clinical and electrophysiologic characteristics of children with cochlear nerve deficiency presenting with AN.
- To determine the prevalence of cochlear nerve deficiency in a cohort of children with AN.
Main Methods:
- Retrospective review of clinical records, audiological tests (ABR, otoacoustic emissions), and magnetic resonance imaging (MRI) in 51 children with AN characteristics.
- Analysis of cochlear nerve size and internal auditory canal dimensions on MRI.
Main Results:
- Nine (18%) children had cochlear nerve deficiency (2 small, 7 absent nerves).
- Most presented after failing newborn hearing screening; ABR showed cochlear microphonics with absent neural responses.
- Unilateral AN was seen in 56% and bilateral in 44%; only one ear had present otoacoustic emissions.
Conclusions:
- Cochlear nerve deficiency is a relatively common cause of AN in children.
- MRI is recommended for all children diagnosed with AN.
- Unilateral AN with profound hearing loss warrants suspicion for cochlear nerve deficiency; management depends on nerve presence.
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