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Updated: May 23, 2026
09:44
Neuro-rehabilitation Approach for Sudden Sensorineural Hearing Loss
Published on: January 25, 2016
Unilateral auditory neuropathy caused by cochlear nerve deficiency
Cheng Liu1, Xingkuan Bu, Feiyun Wu
1WHO Collaborating Centre for the Prevention of Deafness and Hearing Impairment, Nanjing Medical University, Nanjing 210029, China.
International Journal of Otolaryngology
|April 21, 2012
Summary
Cochlear nerve deficiency (CND) is a significant cause of unilateral auditory neuropathy (AN). Oblique sagittal MRI of the internal auditory canal is recommended for diagnosing CND and AN.
Area of Science:
- Audiology
- Neurology
- Radiology
Background:
- Unilateral auditory neuropathy (AN) presents diagnostic challenges.
- Cochlear nerve deficiency (CND) is a potential underlying cause of AN.
Purpose of the Study:
- To investigate the correlation between CND and unilateral AN.
- To identify diagnostic markers for CND in AN patients.
Main Methods:
- Retrospective review of audiological and radiological records of 85 patients with unilateral profound sensorineural hearing loss.
- Diagnosis of unilateral AN based on evoked otoacoustic emissions (EOAEs) or cochlear microphonic (CM).
- Analysis of auditory brainstem responses (ABRs) and oblique sagittal MRI of the internal auditory canal.
Main Results:
- Eight cases of unilateral AN were attributed to CND.
- Most patients had normal tympanograms and EOAEs, with abnormal ABRs.
- MRI revealed absent or poorly visualized cochlear nerves in affected ears.
Conclusions:
- CND is an electrophysiologically identifiable cause of unilateral AN.
- Inclined sagittal MRI is crucial for diagnosing CND-related unilateral AN.
- Early diagnosis of CND can guide appropriate management strategies.
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