Longitudinal Development of Wideband Absorbance and Admittance Through Infancy

Abstract

Purpose The aim of this article was to study the normal longitudinal development of wideband absorbance and admittance measures through infancy. Method Two hundred one infants who passed the newborn hearing screen (automated auditory brainstem response) were tested at birth and then followed up at approximately 6, 12, and 18 months of age. Most infants were of either White (86%) or Asian (11%) descent. At each test session, infants passed tympanometry and distortion product otoacoustic emission tests. High-frequency (1000-Hz) tympanometry was used at birth and 6 months of age, and low-frequency (226-Hz) tympanometry was used at 12 and 18 months of age. Wideband pressure reflectance was also measured at each session and analyzed in terms of absorbance, admittance at the probe tip, and admittance normalized for differences in ear canal area. Multilevel hierarchical models were fitted to the absorbance and admittance data to investigate for effects of age, ear side, gender, ethnicity, and frequency. Results There were considerable age effects on wideband absorbance and admittance measurements over the first 18 months of life. The most dramatic changes occurred between birth and 6 months of age, and there were significant differences between all age groups in the 3000- to 4000-Hz region. There were significant ethnicity effects that were substantial for certain combinations of ethnicity, age, and frequency (e.g., absorbance at 6000 Hz at 12 months of age). Conclusion There are large developmental effects on wideband absorbance and admittance measures through infancy. For absorbance, we recommend separate reference data be used at birth, 6 months of age, and 12–18 months of age. For admittance (both normalized and at the probe tip), we advise using separate normative regions for each age group (neonates and 6, 12, and 18 months).

Diagnosing conductive dysfunction in infants using wideband acoustic immittance: development and validation of predictive models

“…This study was part of a larger project that followed 753 infants from birth (Myers et al, 2018a(Myers et al, , 2018b(Myers et al, , 2019c…”

“…Although preliminary studies in infants have reported strong performance Myers et al, 2018b;Prieve et al, 2013b), more diagnostic research in this age group is necessary, as WAI could be a valuable tool for identifying middle ear pathology early in childhood. Furthermore, research is needed on different age groups through infancy, as there are large developmental effects on the WAI response that are not yet complete by 24 months of age (Keefe et al, 1993;Kei et al, 2013;Myers et al, 2019c). Ellison et al (2012) included some 12-month-old infants in their study, but the age of the 88 children in the sample ranged from 6 months to 7 years.…”

“…An issue with developing such algorithms for use with infants, however, is that there are substantial maturational effects on WAI that need to be controlled for (Aithal et al, 2014b;Hunter et al, 2010;Hunter et al, 2016;Keefe et al, 1993;Keefe et al, 2000;Kei et al, 2013;Myers et al, 2018aMyers et al, , 2019cSanford et al, 2009;Shahnaz et al, 2014;Werner et al, 2010). One solution to this problem has been to create age-specific algorithms, such as models that have been developed for neonates Myers et al, 2018a;Sanford et al, 2009) or different age groups through infancy (Myers et al, 2018b(Myers et al, , 2019b.…”

“…One solution to this problem has been to create age-specific algorithms, such as models that have been developed for neonates Myers et al, 2018a;Sanford et al, 2009) or different age groups through infancy (Myers et al, 2018b(Myers et al, , 2019b. Alternatively, models could be developed with age included as an interaction term with WAI, which would allow interpretation to vary with age (Myers et al, 2019c). Another approach would be to only include frequency regions that are relatively unaffected by age as predictors in a model (Myers et al, 2019c;Sanford & Feeney, 2008).…”

“…Alternatively, models could be developed with age included as an interaction term with WAI, which would allow interpretation to vary with age (Myers et al, 2019c). Another approach would be to only include frequency regions that are relatively unaffected by age as predictors in a model (Myers et al, 2019c;Sanford & Feeney, 2008). For example, for infants aged 0 to 6 months, Shahnaz et al (2014) found limited developmental effects on R from 600 to 1600 Hz, and Sanford and Feeney (2008) Another issue in diagnostic WAI research is that although many predictive models have been developed Keefe et al, 2003a;Keefe et al, 2003b;Myers et al, 2018aMyers et al, , 2018bMyers et al, , 2019bPiskorski et al, 1999;Sanford et al, 2009), none have been validated in an external sample of subjects.…”