Signal-to-noise ratio improvement of swept-tone-generated transient otoacoustic emissions

In this study, we utilized the swept-tone (ST) deconvolution method for comparing the signal-to-noise ratio (SNR) characteristics of ST otoacoustic emissions (OAE) to conventionally acquired click, or transient-evoked (TE), OAE. We generated a hearing-level equalized (HLeq) ST stimulus based on normative loudness metrics at the different frequencies present in the ST. Due to noise-shaping properties of the ST deconvolution method, we anticipated a theoretical SNR gain of +4.26 dB in STOAE compared to TEOAE acquired under comparable settings. This prediction was confirmed by computer simulation. HLeq STOAE and TEOAE were then acquired from each of the 22 ears that were tested at five stimulation levels from 5 to 45 dB HL, and analyzed responses in terms of their overall SNR. We found that the overall SNR of the HLeq STOAE responses at stimulation levels at or above 15 dB HL was significantly higher than that of TEOAE by an average of +3.6 dB. Importantly, this leads to recording quality and time-saving improvements in clinical hearing screenings.