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Published on: February 29, 2020
Partitioned Internal Auditory Canal: Association With Cochlear Aperture Anomalies
Levent Sennaroğlu1, Emel Tahir2
1Department of Otolaryngology, Hacettepe University School of Medicine, Ankara, Turkey.
The Laryngoscope
|May 16, 2026
Summary
Partitioned internal auditory canal (IAC) is linked to cochlear aperture abnormalities and narrow IAC. This inner ear malformation often involves cochlear nerve (CN) deficiency, impacting facial nerve development.
Area of Science:
- Radiology and Imaging
- Otolaryngology
- Neuroscience
Background:
- Partitioned internal auditory canal (IAC) is a rare inner ear malformation.
- Understanding its association with other inner ear abnormalities is crucial for diagnosis and management.
Purpose of the Study:
- To investigate the relationship between partitioned IAC and inner ear abnormalities, including cochlear aperture (CA) and cochlear nerve (CN) status.
Main Methods:
- Retrospective analysis of temporal bone CT and MRI scans from patients with partitioned IAC.
- Classification of IAC diameter, CA diameter (normal, stenotic, atretic), and CN status (normal, hypoplastic, aplastic).
Main Results:
- Partitioned IAC occurred in 1.1% of normal CA ears, 14.9% of stenotic CA ears, and 20.9% of atretic CA ears.
- Partitioned IAC was frequently associated with narrow IAC and cochlear nerve deficiency (aplasia or hypoplasia).
Conclusions:
- Partitioned IAC is an inner ear malformation characterized by cochlear nerve deficiency.
- CN deficiency and CA abnormalities may lead to aberrant facial nerve development within a separate bony canal.
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