Normative Wideband Acoustic Immittance Measurements in Caucasian and Aboriginal Children

Abstract

Purpose The aims of this study were to develop normative data for wideband acoustic immittance (WAI) measures in Caucasian and Australian Aboriginal children and compare absorbance measured at 0 daPa (WBA 0 ) and tympanometric peak pressure (TPP; WBA TPP ) between the 2 groups of children. Additional WAI measures included resonance frequency, equivalent ear canal volume, TPP, admittance magnitude (YM), and phase angle (YA). Method A total of 171 ears from 171 Caucasian children and 87 ears from 87 Aboriginal children who passed a test battery consisting of 226-Hz tympanometry, transient evoked otoacoustic emissions, and pure tone audiometry were included in the study. WAI measures were obtained under pressurized conditions using wideband tympanometry. Data for WBA 0 , WBA TPP , YM, and YA were averaged in one-third octave frequencies from 0.25 to 8 kHz. Results There was no significant ear effect on all of the 7 measures for both groups of children. Similarly, there was no significant gender effect on all measures except for WBA TPP in Aboriginal children. Aboriginal boys had significantly higher WBA TPP than girls at 1.5 and 2 kHz. A significant effect of ethnicity was also noted for WBA TPP at 3, 4, and 8 kHz, with Caucasian children demonstrating higher WBA TPP than Aboriginal children. However, the effect size and observed power of the analyses were small for both effects. Conclusion This study developed normative data for 7 WAI measures, namely, WBA 0 , WBA TPP , TPP, Veq, RF, YM, and YA, for Caucasian and Aboriginal children. In view of the high similarity of the normative data between Caucasian and Aboriginal children, it was concluded that separate ethnic-specific norms are not required for diagnostic purposes.

Wideband Tympanometry Findings in School-aged Children: Effects of Age, Gender, Ear Laterality, and Ethnicity

“…Figure 4 shows the similarities between the WBA 0 data from the 4–6 year group of the present study and the WBA a data from two of these reports concerning age-comparable groups of children (Beers et al 2010; Mishra et al 2017). The present study is in agreement with these previous reports showing absorbance to be highest between 1000 and 5000 Hz for all age groups and provides further support to the suggestion that this frequency region might be most sensitive to identify reduced middle-ear transmission and particularly relevant for clinical applications (Ellison et al 2012; Keefe et al 2012; Sanford & Brockett 2014; V. Aithal et al 2019).…”

“…The present study suggests that gender-specific norms are not required. This is in agreement with the aforementioned work of S. Aithal et al (2019) despite the small but statistically significant gender-based differences in WBA TPP of Australian Aboriginal children. Further, Beers et al (2010) reported no effect of gender on WBA a of children aged 5 to 6 years.…”

“…In the present study, ethnicity and ear laterality were concluded to be clinically irrelevant factors. This is consistent with the findings of V. Aithal et al (2019) who, in an age-comparable sample of Caucasian and Australian Aboriginal children (mean ages 7.2 and 8.1 years, respectively), concluded that ethnicity-specific clinical norms were not necessary despite the presence of statistically significant differences between the groups. Further, there was no evidence of ear effects on WBT values in either group of children, nor in a later study of 38 children aged 4 to 11 years (V. Aithal et al 2020).…”

“…TPP was the pressure at which the maximum of the low-frequency (0.376 to 2.0 kHz) averaged absorbance occurred. One-third octave averaging was used to create 16 frequency bands with the 250-Hz and the 8000-Hz bands being constrained by the lower and upper limits, respectively, as per the V. Aithal et al (2019) study.…”

Wideband Absorbance in Ears with Retraction Pockets and Cholesteatomas: A Preliminary Study

“…Although there are differences in WBA due to developmental effects, these differences are too small to be of clinical significance. 42 Second, although the acoustic measures are dependent on the status of the middle ear ossicles, staging of each ossicle was not considered in the present study. Staging of ossicular chain can be used to quantify the extent of erosion of each ossicle.…”