title: Post-processing analysis of transient-evoked otoacoustic emissions to detect 4 kHz-notch hearing impairment--a pilot study.
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.
  
  
  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.
authors.affiliation: Institute of Otolaryngology, Catholic University School of Medicine, Rome, Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Zimatore
authors.forename: Anna Rita
authors.initials: AR
authors.lastname: Fetoni
authors.forename: Gaetano
authors.initials: G
authors.lastname: Paludetti
authors.forename: Marta
authors.initials: M
authors.lastname: Cavagnaro
authors.forename: Maria Vittoria
authors.initials: MV
authors.lastname: Podda
authors.forename: Diana
authors.initials: D
authors.lastname: Troiani
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001301:Audiometry, Pure-Tone / Q000379:methods*; D001309:Auditory Threshold / Q000502:physiology; D001489:Basilar Membrane / Q000503:physiopathology; D034381:Hearing Loss / Q000175:diagnosis* / Q000503:physiopathology*; D006801:Humans; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*; D010865:Pilot Projects; D012015:Reference Standards