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Neuro-rehabilitation Approach for Sudden Sensorineural Hearing Loss
Published on: January 25, 2016
Interaural attenuation for Sennheiser HDA 200 circumaural earphones
K Jonas Brännström1, Johannes Lantz
1Department of Clinical Science, Lund University, Lund, Sweden. jonas.brannstrom@med.lu.se
International Journal of Audiology
|May 21, 2010
Summary
Sennheiser HDA 200 earphones offer superior interaural attenuation (IA) compared to TDH-39P, crucial for accurate pure-tone audiometry in unilaterally deaf individuals. Contralateral masking is recommended with HDA 200 when test ear levels exceed 40 dB above non-test ear thresholds.
Area of Science:
- Audiology
- Hearing Science
- Medical Devices
Background:
- Accurate hearing assessments require understanding interaural attenuation (IA) differences between audiometric earphones.
- Unilateral hearing loss presents unique challenges in audiology, necessitating precise masking protocols.
Purpose of the Study:
- To compare the interaural attenuation (IA) of Sennheiser HDA 200 and Telephonics TDH-39P earphones for pure tones.
- To provide evidence-based recommendations for contralateral masking during audiometry in unilaterally deaf subjects.
Main Methods:
- Investigated IA across pure tones (125-16000 Hz) in nine unilaterally deaf participants.
- Utilized Sennheiser HDA 200 and Telephonics TDH-39P earphones.
- Employed 1-dB step manual ascending audiometry per ISO 8253-1 standards.
Main Results:
- Sennheiser HDA 200 demonstrated a minimum IA of 42 dB across all tested frequencies.
- TDH-39P earphone IA values aligned with previously reported data.
- HDA 200 provided significantly greater IA than TDH-39P, particularly at frequencies ≤500 Hz.
Conclusions:
- Sennheiser HDA 200 earphones offer enhanced interaural attenuation, beneficial for audiological testing.
- Contralateral masking is advised when using HDA 200 earphones if the test ear signal exceeds the non-test ear's threshold by over 40 dB.
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