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Published on: February 21, 2016
Human cochleae with three turns: an unreported malformation
Qing Tian1, Fred H Linthicum, Jose N Fayad
1Healthcare Partners, Torrance, California 90057, USA.
The Laryngoscope
|May 3, 2006
Summary
Human cochleae with three turns, a rare anomaly, were identified in a histologic study. These unique cochleae feature longer basilar membranes compared to normal structures.
Area of Science:
- Anatomy
- Histology
- Human Morphology
Background:
- The human cochlea typically has two and a half turns.
- Anatomical variations in the cochlea are crucial for understanding auditory function.
Purpose of the Study:
- To describe the morphology of human cochleae exhibiting an unreported three-turn anomaly.
- To document this anomaly using archival temporal bone sections.
Main Methods:
- Histopathologic processing of archival temporal bone sections.
- Measurement of basilar membrane length in anomalous and control specimens.
- Comparison of basilar membrane length between three-turn cochleae and normal cochleae.
Main Results:
- Identification of human cochleae with three complete turns, a previously undocumented variation.
- Anomalous cochleae demonstrated significantly longer basilar membranes (mean 40.6 mm) than normal controls (mean 33.8 mm).
Conclusions:
- Human cochleae with three turns represent a novel anatomical anomaly.
- This anomaly is unlikely to result from developmental interruption, suggesting alternative etiologies.
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