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Updated: Jul 23, 2026
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Morphological and Functional Evaluation of Ribbon Synapses at Specific Frequency Regions of the Mouse Cochlea
Published on: May 10, 2019
Aplasia of the cochlear nerve: a temporal bone study.
1Section of Otolaryngology-Head and Neck Surgery, University of Chicago Medical Center, 5841 S. Maryland Avenue, MC 1035, Chicago, IL 60637, USA.
Summary
Cochlear nerve aplasia can occur with a fully formed cochlea and organ of Corti, independent of the spiral ganglion. This finding is crucial for evaluating cochlear implant candidacy in deaf individuals.
Area of Science:
- Otolaryngology
- Neuroscience
- Developmental Biology
Background:
- Cochlear nerve aplasia is a rare cause of profound unilateral deafness.
- Understanding the developmental relationship between the cochlear nerve, spiral ganglion, and cochlea is essential.
Observation:
- A retrospective review examined temporal bones from two individuals with cochlear nerve aplasia.
- Histopathologic analysis quantified cochlear elements and assessed the organ of Corti.
Findings:
- A fully formed cochlea and normal-appearing organ of Corti were observed despite the absence of the cochlear nerve and spiral ganglion.
- Cochlear nerve aplasia can occur with both narrow and normal-sized internal auditory canals.
Implications:
- Cochlear and organ of Corti development may not be dependent on the cochlear nerve or spiral ganglion.
- Cochlear nerve aplasia with a normal cochlea should be considered in cochlear implantation candidacy evaluations.
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01:13The Cochlea
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01:16Anatomy of the Ear
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