
Effects of Forward- and Emitted-Pressure Calibrations on the Variability of Otoacoustic Emission Measurements Across Repeated Probe Fits
Author(s) -
Tom Maxim,
Christopher A. Shera,
Karolina K. Charaziak,
Carolina Abdala
Publication year - 2019
Publication title -
ear and hearing
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.577
H-Index - 109
eISSN - 1538-4667
pISSN - 0196-0202
DOI - 10.1097/aud.0000000000000714
Subject(s) - otoacoustic emission , calibration , environmental science , acoustics , audiology , medicine , physics , mathematics , statistics , hearing loss
The stimuli used to evoke otoacoustic emissions (OAEs) are typically calibrated based on the total SPL measured at the probe microphone. However, due to the acoustics of the ear-canal space (i.e., standing-wave interference), this method can underestimate the stimulus pressure reaching the tympanic membrane at certain frequencies. To mitigate this effect, stimulus calibrations based on forward pressure level (FPL) can be applied. Furthermore, the influence of ear-canal acoustics on measured OAE levels can be compensated by expressing them in emitted pressure level (EPL). To date, studies have used artificial shallow versus deep probe fits to assess the effects of calibration method on changes in probe insertion. In an attempt to better simulate a clinical setting, the combined effects of FPL calibration of stimulus level and EPL compensation of OAE level on response variability during routine (noncontrived) probe fittings were examined.