The influence of otitis media with effusion on middle-ear impedance estimated from wideband acoustic immittance measurements.

The goal of this work was to estimate the middle-ear input impedance ( Zme) from wideband acoustic immittance (WAI) measures and determine whether Zme improves the clinical utility of WAI. The data used in this study were from a previously reported set of WAI measurements in ears with otitis media with effusion [OME; Merchant, Al-Salim, Tempero, Fitzpatrick, and Neely (2021). Ear Hear., published online]. Ears with OME were grouped based on effusion volume, which was confirmed during tube surgery. Zme was estimated from the measured ear-canal impedance. An electrical-analog model of ear-canal acoustics and middle-ear mechanics was used to model the ear canal and Zme. The model results fit the measured responses well for all conditions. A regression approach was used to classify the responses of different variable types to effusion volume groups and determine the specificity and sensitivity of the binary classifications. The Zme magnitude increased with increasing effusion volume. The area under the receiver operating characteristic curve (AUC) was compared for binary decisions of the OME categories. The Zme estimate resulted in a clinically meaningful improvement in the AUC for distinguishing healthy ears from ears with OME. Overall, these results suggest that Zme estimation may provide useful information of potential clinical value to improve the diagnostic utility of WAI measurements for OME.