The Rise and Fall of Aural Acoustic Immittance Assessment Tools

High Signal to Noise Ratio Piezoelectric Thin Film Sensor Based on Elastomer Amplification for Ambulatory Blood Pressure Monitoring

Continuous pulse wave detection can be used for monitoring and diagnosing cardiovascular diseases, and research on pulse sensing based on piezoelectric thin films is one of the hot spots. Usually, piezoelectric thin films do not come into direct contact with the skin and need to be connected through a layer of an elastic medium. Most views think that the main function of this layer of elastic medium is to increase the adhesion between the sensor component and the skin, but there is little discussion about the impact of the elastic medium on pulse vibration transmission. Here, we conducted a detailed study on the effects of Young's modulus and the thickness of elastic media on pulse sensing signals. The results show that the waveform amplitude of the piezoelectric sensing signal decreases with the increase of Young's modulus and thickness of the elastic medium. Then, we constructed a theoretical model of the influence of elastic media on pulse wave propagation. The amplitude of the pulse wave signal detected by the optimized sensor was increased to 480%. Our research shows that by regulating Young's modulus and thickness of elastic media, pulse wave signals can undergo a similar amplification effect, which has an important theoretical reference value for achieving ambulatory blood pressure monitoring based on high-quality pulse waves.

Survey of Wideband Acoustic Immittance Use by Clinical Audiologists

PURPOSE

Wideband acoustic immittance (WAI) is a promising measure of middle-ear mechanics. In contrast to standard tympanometry, which is generally measured at a single stiffness-dominated low frequency, WAI detects mechanical effects on both the mass and stiffness properties of the middle ear across a wide range of frequencies, resulting in a more comprehensive assessment of middle-ear mechanics in healthy and pathological ears. Despite a plethora of research demonstrating the clinical utility of this measure, clinical adoption of WAI is still limited. This work explores audiologists' use and perceptions of WAI, with the goal of identifying the barriers to its clinical adoption.

METHOD

A survey on the perception and use of WAI by clinical audiologists in the United States was developed and administered using the Research Electronic Data Capture application. The survey was distributed broadly across the United States. Participation was voluntary and anonymous, and no compensation was provided.

RESULTS

Findings from 132 survey respondents across 32 states were included in the analyses. Overall, findings suggest the largest barriers to clinical adoption of WAI are lack of access to equipment that measures WAI and lack of training and/or confidence in measuring or interpreting WAI.

CONCLUSIONS

Several barriers to clinical adoption of WAI were identified. However, findings also provide optimism in that audiologists utilizing WAI find it more useful than standard tympanometry, and most audiologists who do not currently use WAI are open to implementing the measure in their clinical practice. We proposed steps to address the highest priority issues and increase the clinical viability of WAI.

Development and Application of a Reference Interval Approach to Wideband Absorbance Norms Using U.S. Population Data for Ages 6 to 80+ Years

PURPOSE

U.S. national wideband absorbance (WBA) data for 17,446 ears included in the National Health and Nutrition Examination Surveys for 2015-2016 and 2017-2020 were analyzed to develop and apply normative reference intervals (RIs).

METHOD

Analyses used distribution-free medians and cumulative distribution functions (CDFs). Notable differences between medians were defined as those with non-overlapping 95% confidence intervals, and differences between CDFs were evaluated using Cohen's h effect size. Strict inclusion criteria identified "healthy ears" with 1,240 ears meeting all the inclusion criteria for the reference group. RIs, WBA values corresponding to the 2.5th and 97.5th percentiles for the reference group, were established. The established RIs were then applied to the full unscreened data set to determine the prevalence of WBA values outside the RIs.

RESULTS

WBA RIs were established for all 6- to 19-year-olds and for 20- to 69-year-olds separated into three groups: females, males, and non-Hispanic Asians. The differences among the CDFs underlying these RIs corresponded to small effect sizes. When a single RI, 0.40 < average WBA < 0.75, was applied to the full data set, about 6%-13% of ears fell outside the derived RIs. Logistic regression analyses found abnormal tympanometric results to be responsible for the extreme WBA values among the general population. Abnormal tympanometric results increased the odds of having WBA values outside the RI by ≥ 300%.

CONCLUSIONS

U.S. population data for healthy ears were used to establish RIs for WBA of about 0.40-0.75. About 6%-13% of Americans, 6-80+ years of age, had WBA values outside these RI limits.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.24185745.