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Post-processing analysis of transient-evoked otoacoustic emissions to detect 4 kHz-notch hearing impairment--a pilot study.

Zimatore G, Fetoni AR, Paludetti G, Cavagnaro M, Podda MV, Troiani D - Med. Sci. Monit. (2011)

Bottom Line: Audiometric examinations indicated 14 ears as impaired-hearing (IH), while the TEOAE ILO92 whole reproducibility parameter (WWR) indicated as IH 7 signals out of 14 (50%).The proposed new parameter indicated as IH 9 signals out of 14 (64%), reducing the number of false negative cases of WWR.In this preliminary study there is evidence that the new parameter RAD2D defines the topology and the quantification of the damage in the inner ear.

View Article: PubMed Central - PubMed

Affiliation: Institute of Otolaryngology, Catholic University School of Medicine, Rome, Italy.

ABSTRACT

Background: To identify a parameter to distinguish normal hearing from hearing impairment in the early stages. The parameter was obtained from transient-evoked otoacoustic emissions (TEOAEs), overcoming the limitations of the usually adopted waveform descriptive parameters which may fail in standard clinical screenings.

Material/methods: Audiometric examinations and TEOAE analysis were conducted on 15 normal ears and on 14 hearing-impaired ears that exhibited an audiometric notch around 4 kHz. TEOAE signals were analyzed through a multivariate technique to filter out the individual variability and to highlight the dynamic structure of the signals. The new parameter (named radius 2-dimension--RAD2D) was defined and evaluated for simulated TEOAE signals modeling a different amount of hearing impairment.

Results: Audiometric examinations indicated 14 ears as impaired-hearing (IH), while the TEOAE ILO92 whole reproducibility parameter (WWR) indicated as IH 7 signals out of 14 (50%). The proposed new parameter indicated as IH 9 signals out of 14 (64%), reducing the number of false negative cases of WWR.

Conclusions: In this preliminary study there is evidence that the new parameter RAD2D defines the topology and the quantification of the damage in the inner ear. The proposed protocol can be useful in hearing screenings to identify hearing impairments much earlier than conventional pure tone audiometry and TEOAE pass/fail test.

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Related in: MedlinePlus

The profile of the traveling wave in the basilar membrane (BM volume velocity) simulated by the electronic model of the ear. The lines show the volume velocity at a fixed instant (8.9 ms) after the onset of the stimulus. The bold line corresponds to the simulation of the normal hearing ear whereas the shaded grey line to the simulation of noise damage. The full circles represent the characteristic frequencies (CF) along the cochlea (axis on the right, kHz), the open circles (see arrow) are relative to the two partitions where the generators gain have been switched off (3854 Hz and 4145 Hz) in the simulated IH signal.
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f3-medscimonit-17-6-mt41: The profile of the traveling wave in the basilar membrane (BM volume velocity) simulated by the electronic model of the ear. The lines show the volume velocity at a fixed instant (8.9 ms) after the onset of the stimulus. The bold line corresponds to the simulation of the normal hearing ear whereas the shaded grey line to the simulation of noise damage. The full circles represent the characteristic frequencies (CF) along the cochlea (axis on the right, kHz), the open circles (see arrow) are relative to the two partitions where the generators gain have been switched off (3854 Hz and 4145 Hz) in the simulated IH signal.

Mentions: The profile of the traveling wave along the basilar membrane (BM volume velocity) simulated by the electronic model of the ear is shown in Figure 3 for normal hearing (bold line) and IH (shaded grey line) ear. In this case, IH was simulated by zeroing the generators gain in 2 consecutive cochlear partitions working close to 4 kHz. BM volume velocity was obtained by using a pure tone stimulus at 4 kHz and by plotting the current values evaluated in each cochlear section at a fixed instant of time (8.9 ms in Figure 3). The behavior evaluated for the normal hearing ear (bold line in Figure 3) is the typical BM volume velocity reported by several authors [36,41]. The black circle symbols placed upon the plot represent the value of the characteristic frequencies (CF) corresponding to the different positions along the cochlea. Comparing the BM volume velocity obtained in normal and IH ears, it is possible to observe that the largest difference is around the frequency of 4 kHz, as expected (see arrow and grey circles).


Post-processing analysis of transient-evoked otoacoustic emissions to detect 4 kHz-notch hearing impairment--a pilot study.

Zimatore G, Fetoni AR, Paludetti G, Cavagnaro M, Podda MV, Troiani D - Med. Sci. Monit. (2011)

The profile of the traveling wave in the basilar membrane (BM volume velocity) simulated by the electronic model of the ear. The lines show the volume velocity at a fixed instant (8.9 ms) after the onset of the stimulus. The bold line corresponds to the simulation of the normal hearing ear whereas the shaded grey line to the simulation of noise damage. The full circles represent the characteristic frequencies (CF) along the cochlea (axis on the right, kHz), the open circles (see arrow) are relative to the two partitions where the generators gain have been switched off (3854 Hz and 4145 Hz) in the simulated IH signal.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3539534&req=5

f3-medscimonit-17-6-mt41: The profile of the traveling wave in the basilar membrane (BM volume velocity) simulated by the electronic model of the ear. The lines show the volume velocity at a fixed instant (8.9 ms) after the onset of the stimulus. The bold line corresponds to the simulation of the normal hearing ear whereas the shaded grey line to the simulation of noise damage. The full circles represent the characteristic frequencies (CF) along the cochlea (axis on the right, kHz), the open circles (see arrow) are relative to the two partitions where the generators gain have been switched off (3854 Hz and 4145 Hz) in the simulated IH signal.
Mentions: The profile of the traveling wave along the basilar membrane (BM volume velocity) simulated by the electronic model of the ear is shown in Figure 3 for normal hearing (bold line) and IH (shaded grey line) ear. In this case, IH was simulated by zeroing the generators gain in 2 consecutive cochlear partitions working close to 4 kHz. BM volume velocity was obtained by using a pure tone stimulus at 4 kHz and by plotting the current values evaluated in each cochlear section at a fixed instant of time (8.9 ms in Figure 3). The behavior evaluated for the normal hearing ear (bold line in Figure 3) is the typical BM volume velocity reported by several authors [36,41]. The black circle symbols placed upon the plot represent the value of the characteristic frequencies (CF) corresponding to the different positions along the cochlea. Comparing the BM volume velocity obtained in normal and IH ears, it is possible to observe that the largest difference is around the frequency of 4 kHz, as expected (see arrow and grey circles).

Bottom Line: Audiometric examinations indicated 14 ears as impaired-hearing (IH), while the TEOAE ILO92 whole reproducibility parameter (WWR) indicated as IH 7 signals out of 14 (50%).The proposed new parameter indicated as IH 9 signals out of 14 (64%), reducing the number of false negative cases of WWR.In this preliminary study there is evidence that the new parameter RAD2D defines the topology and the quantification of the damage in the inner ear.

View Article: PubMed Central - PubMed

Affiliation: Institute of Otolaryngology, Catholic University School of Medicine, Rome, Italy.

ABSTRACT

Background: To identify a parameter to distinguish normal hearing from hearing impairment in the early stages. The parameter was obtained from transient-evoked otoacoustic emissions (TEOAEs), overcoming the limitations of the usually adopted waveform descriptive parameters which may fail in standard clinical screenings.

Material/methods: Audiometric examinations and TEOAE analysis were conducted on 15 normal ears and on 14 hearing-impaired ears that exhibited an audiometric notch around 4 kHz. TEOAE signals were analyzed through a multivariate technique to filter out the individual variability and to highlight the dynamic structure of the signals. The new parameter (named radius 2-dimension--RAD2D) was defined and evaluated for simulated TEOAE signals modeling a different amount of hearing impairment.

Results: Audiometric examinations indicated 14 ears as impaired-hearing (IH), while the TEOAE ILO92 whole reproducibility parameter (WWR) indicated as IH 7 signals out of 14 (50%). The proposed new parameter indicated as IH 9 signals out of 14 (64%), reducing the number of false negative cases of WWR.

Conclusions: In this preliminary study there is evidence that the new parameter RAD2D defines the topology and the quantification of the damage in the inner ear. The proposed protocol can be useful in hearing screenings to identify hearing impairments much earlier than conventional pure tone audiometry and TEOAE pass/fail test.

Show MeSH
Related in: MedlinePlus