Related Experiment Videos
[Rare audiometry findings in progressive, monosymptomatic low frequency deafness]
U Hoppe1, F Rosanowski, W Delb
1Abteilung für Phoniatrie und Pädaudiologie, Klinikum der Universität Erlangen-Nürnberg, Bohlenplatz 21, 91054 Erlangen. ulrich.hoppe@phoni.imed.uni-erlangen.de
HNO
|October 12, 2001
Summary
Objective audiometry, including auditory evoked potentials, has limitations. This case study highlights how click-evoked auditory evoked brainstem responses can yield false negatives, suggesting auditory cortical potentials may offer better insights in specific cases.
Area of Science:
- Audiology
- Neuroscience
- Otoacoustic Emissions
Background:
- Objective audiometric methods like otoacoustic emissions and auditory evoked potentials offer valuable insights into hearing function.
- However, each method has inherent limitations and restrictions, necessitating a comprehensive approach.
Observation:
- Puretone audiometry revealed a severe low-frequency hearing loss, progressing to near-normal thresholds at higher frequencies.
- Transitory evoked otoacoustic emissions were undetectable.
- While click-evoked auditory evoked brainstem responses appeared normal, notched-noise auditory evoked brainstem responses were not reproducible.
Findings:
- Click-evoked auditory evoked brainstem responses, often considered the gold standard, can produce false negative results in specific audiometric evaluations.
- Auditory tone-evoked cortical potentials demonstrated a normal N1/P2 complex, detectable even at low stimulus levels above hearing threshold.
Implications:
- This case underscores the potential pitfalls of relying solely on click-evoked auditory evoked brainstem responses for objective hearing assessment.
- Auditory tone-evoked cortical potentials may offer superior objective information in challenging cases.
- A thorough understanding of the methodological restrictions and potential pitfalls of all electrophysiological measurements is crucial for accurate hearing threshold determination.