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Updated: May 16, 2026
09:44
Neuro-rehabilitation Approach for Sudden Sensorineural Hearing Loss
Published on: January 25, 2016
Effect of cochlear window fixation on air- and bone-conduction thresholds.
Ben I Nageris1, Joseph Attias, Rafi Shemesh
1Department of Otorhinolaryngology-Head and Neck Surgery, Rabin Medical Center, Petach Tikva, Israel.
Summary
Bone conduction hearing relies on a "third window" when cochlear windows are blocked. This study in fat sand rats demonstrates that even with occluded round and oval windows, bone conduction remains functional, highlighting the third window
Area of Science:
- Auditory physiology
- Cochlear mechanics
- Bone conduction hearing
Background:
- Conflicting results exist regarding air and bone conduction changes with cochlear window occlusion.
- The role of cochlear windows as pressure release outlets is debated.
Purpose of the Study:
- To investigate the role of a "third window" in bone conduction hearing.
- To determine the impact of cochlear window occlusion on auditory brain responses.
Main Methods:
- Auditory brain responses were measured in fat sand rats using air and bone conduction.
- The round window membrane was sealed, and measurements were repeated.
- The stapes footplate was then immobilized, and measurements were taken again.
Main Results:
- Sealing the round window significantly increased air-conduction thresholds.
- Immobilizing the stapes footplate further elevated air-conduction thresholds.
- Bone-conduction thresholds remained unchanged throughout the occlusions.
Conclusions:
- Findings support the existence of a functional "third window" in the cochlea.
- This third window is crucial for bone conduction when conventional cochlear windows are obstructed.
- Bone conduction can displace the cochlear partition independently of patent cochlear windows.
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