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The Mouse Round-window Approach for Ototoxic Agent Delivery: A Rapid and Reliable Technique for Inducing Cochlear Cell Degeneration
Published on: November 26, 2015
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The relationship between round window and ear canal Cochlear microphonic.
Yongqiang Yu1,2,3,4, Junping Liu1, Jastin Antisdel3
1Department of Otolaryngology - Head and Neck Surgery Mindong Hospital, The Affiliated Mindong Hospital of Fujian Medical University Fujian China.
Laryngoscope Investigative Otolaryngology
|December 22, 2022
Summary
Cochlear microphonic recorded at the ear canal (CM-EC) can substitute for round window recordings (CM-RW). This non-invasive method accurately reflects hearing function and supports clinical use.
Area of Science:
- Auditory Neuroscience
- Otoacoustic Emissions
- Hearing Science
Background:
- Cochlear microphonic (CM) recordings at the ear canal (CM-EC) are a non-invasive alternative to round window recordings (CM-RW).
- Tone-burst evoked CM provides more detailed information than click-evoked CM but is technically challenging to record.
- Optimizing CM-EC recording is crucial for its wider clinical application.
Purpose of the Study:
- To investigate the feasibility and significance of recording tone-burst evoked CM-EC across the speech frequency range (0.5-8 kHz).
- To compare CM-EC with CM-RW in guinea pigs with normal hearing and noise-induced hearing loss (NIHL).
- To validate CM-EC as a reliable objective measure for hearing evaluation.
Main Methods:
- Nine guinea pigs were divided into three groups: normal control, low-frequency noise exposure (0.5-2 kHz), and high-frequency noise exposure (6-8 kHz).
- Tone-burst evoked CM-EC and CM-RW were recorded across speech frequencies (0.5-8 kHz) after optimizing recording technology.
- Noise-induced hearing loss was induced using band-noise exposure at 120 dB SPL for 1 hour.
Main Results:
- Successfully recorded CM-EC and CM-RW across the speech frequency spectrum.
- Significant reductions in CM amplitude were observed in noise-exposed groups compared to controls (p < .05), indicating CM sensitivity to NIHL.
- A significant positive correlation was found between CM-RW and CM-EC measurements (p < .05).
Conclusions:
- Tone-burst evoked CM-EC is a sensitive and reliable objective measure for assessing hearing function.
- The strong correlation between CM-EC and CM-RW supports the clinical application of non-invasive CM-EC.
- Optimized CM-EC recording technology facilitates its use in evaluating hearing across speech frequencies, even with NIHL.
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