Study on wideband tympanometry and absorbance within a Danish cohort of normal hearing adults

Measuring resonance frequency of the middle ear in school-aged children: potential applications for detecting middle ear dysfunction

OBJECTIVE

This study established a normative range of resonance frequency (RF) values as estimated using Wideband Tympanometry (WBT) and determined the ability of WBT-estimated RF to predict the presence of middle ear dysfunction in school-aged children.

DESIGN

Cross-sectional data were collected using a hearing screening test battery consisting of WBT, Pure Tone Screening (PTS), 226- kHz tympanometry, and ipsilateral Acoustic Stapedial Reflexes (ASR).

STUDY SAMPLE

About 1590 children aged 4-13 years.

RESULTS

RF significantly decreased from 4 to 13 years of age (4-6 years, 928.95  kHz; 7-9 years, 872.80  kHz; 10-13 years, 863.68  kHz). RF had area under the receiver operating characteristic curve (AROC) values between 0.589 and 0.626 to predict ears that failed PTS or 226- kHz tympanometry. RF below 627  kHz accurately predicted the presence of a Type B tympanogram (AROC 0.945). RF had high test-retest reliability with Intra-Class Coefficient value of 0.817 and good agreement according to Bland-Altman plot analysis.

CONCLUSIONS

WBT-estimated RF had fair diagnostic accuracy for predicting PTS and tympanometry results, but had excellent accuracy for predicting the presence of middle ear dysfunction, indicated by a Type B tympanogram. WBT-estimated RF does not require age-, gender-, ear- or ethnicity-specific normative data for clinical use with children.

Characteristics of large vestibular aqueduct syndrome in wideband acoustic immittance

Objective

To describe the characteristics of large vestibular aqueduct syndrome (LVAS) in wideband acoustic immittance (WAI) and to explore whether inner ear deformity has an impact on WAI results.

Methods

Subjects with typical LVAS (LVAS group) and control subjects with a normal anatomical structure of the inner ear (control group) were screened from pediatric patients with cochlear implants using thin-slice computed tomography (CT) images of the temporal bone. With inflammation of the auditory canal and middle ear excluded by routine ear examination and 226 Hz acoustic immittance, WAI data were acquired. Then, the maximum absorbance as the major observation indicator on the mean tympanogram was compared between the LVAS group and control group, and a descriptive comparison of the mean tympanogram and frequency-absorbance curve at peak pressure was performed between the two groups.

Results

The LVAS group included 21 cases (38 ears), and the control group included 27 cases (45 ears). All LVAS subjects met the Valvassori criteria, and the VA at the horizontal semicircular canal displayed flared expansion. On the mean tympanogram, the maximum absorbance in the LVAS group (0.542 ± 0.087) was significantly higher than that in the control group (0.455 ± 0.087) (p < 0.001). The tympanogram in the LVAS group showed an overall elevation, and the absorbance at all pressure sampling points was significantly higher than that in the control group (p < 0.001). The frequency-absorbance curve at peak pressure first increased and then decreased in both groups, and the LVAS group showed higher absorbance than the control group in the frequency range below 2,828 Hz. The absorbance at 343-1,124 Hz was significantly different between the two groups (p < 0.001), and 343-1,124 Hz was the major frequency range at which the maximum absorbance on the mean tympanogram increased in the LVAS group.

Conclusion

Large vestibular aqueduct syndrome (LVAS) shows increased absorbance in low and medium frequency ranges in WAI. The maximum absorbance on the mean tympanogram can serve as a reliable evaluation indicator. Inner ear factors must be considered when middle ear lesions are analyzed by WAI.

Evaluation of middle ear and hearing status of ankylosing spondylitis patients with wideband tympanometry and pure tone audiometry tests

OBJECTIVES

The aim of this study was to evaluate the middle and inner ear function and hearing status of Ankylosing spondylitis (AS) patients.

METHODS

One hundred twenty-four ears of 62 patients with AS and 90 ears (control group) of 45 healthy subjects were included in the study. The hearing levels of the participants were assessed with pure tone and high-frequency audiometry at the octave frequency between 250 and 16,000 Hz. The absorbance rates and resonance frequencies of middle ear were measured with the wideband tympanometry (WBT) test. AS group was divided into subgroups based on the disease activity, duration of follow-up, medications used for AS, and the subgroups were compared according to hearing status and absorbance and resonance frequencies of middle ears.

RESULTS

A statistically significant difference was found between the AS and control groups in terms of air and bone conduction thresholds at frequencies of 250, 500, 1000, 2000, and 4000 Hz and the mean PTA₁, PTA₂, and PTA₃ values (p < 0.05). In contrast, no statistically significant difference was observed between two groups in terms of high-frequency thresholds (8000-16,000 Hz). Although the middle ear resonance frequency obtained from the WBT test was higher in the AS group compared to the control group, no significant difference was observed (p > 0.05). The severity of disease adversely affected the hearing threshold at 250, and 500 Hz for air conduction, at 500 Hz for bone conduction threshold, and at PTA₁ (p < 0.05). The duration and severity of disease did not affect absorbance values of WBT (p > 0.05).

CONCLUSION

To our knowledge, this is the first study to demonstrate the effects of AS patients on the middle ear function with WBT and to report middle ear absorbance values and resonance frequency changes in AS patients. The higher resonance frequency values found by WBT in AS patients may be due to the stiffness that develops as a result of middle ear involvement. According to pure tone and high-frequency audiometry findings, it has been seen that AS leads to SNHL especially at low frequencies.

The Role of Wideband Tympanometry in the Diagnosis of Meniere's Disease

Meniere's disease (MD) is a clinical syndrome characterized by spontaneous recurrent vertigo, usually accompanied by hearing loss, tinnitus, and aural fullness. The cause of MD remains unclear and is generally considered to be associated with endolymphatic hydrops. Studies showed that patients with MD could have eustachian tube dysfunction (ETD). ETD can disrupt the pressure balance between the middle and inner ear and impair the inner ear's function. In recent years, several studies have attempted to identify MD by using wideband tympanometry (WBT). However, there are limited studies in this area. There is no consensus on how to use WBT to diagnose Meniere's disease. Therefore, we endeavored to conduct a narrative review in this aspect based on the latest research findings. Reduction in resonance frequency and absorbance are characteristic of MD and can identify Meniere's disease. The use of an increase in the integrated area of absorbance as an indicator for identifying MD is controversial. WBT seems to be ineffective as a diagnostic tool during the acute episodes of Meniere's disease. Patients with MD may benefit from WBT. WBT has excellent potential for future use in Meniere's disease. However, further large sample sizes, multicenter studies are needed.

Analysing wideband absorbance immittance in normal and ears with otitis media with effusion using machine learning

Wideband Absorbance Immittance (WAI) has been available for more than a decade, however its clinical use still faces the challenges of limited understanding and poor interpretation of WAI results. This study aimed to develop Machine Learning (ML) tools to identify the WAI absorbance characteristics across different frequency-pressure regions in the normal middle ear and ears with otitis media with effusion (OME) to enable diagnosis of middle ear conditions automatically. Data analysis included pre-processing of the WAI data, statistical analysis and classification model development, and key regions extraction from the 2D frequency-pressure WAI images. The experimental results show that ML tools appear to hold great potential for the automated diagnosis of middle ear diseases from WAI data. The identified key regions in the WAI provide guidance to practitioners to better understand and interpret WAI data and offer the prospect of quick and accurate diagnostic decisions.

Wideband tympanometry as a diagnostic tool for Meniere's disease: a retrospective case-control study

PURPOSE

The main purpose of this study was to investigate the usefulness of wide band tympanometry (WBT) as a diagnostic tool for Ménière's disease (MD) by comparing differences in absorbance measures between normal hearing ears and patient diagnosed with MD.

METHODS

We conducted a retrospective case-control study. From a cohort of 116 patients diagnosed with Ménière disease, 52 MD patients and 99 normal hearing adults with no history of otological disease served as subjects. Wideband tympanometry was conducted using at Titan Impedance module and audiometry was performed with a MADSEN Astera². Mean energy absorbance curves with 95% confidence intervals were computed across cases with MD and controls in the frequency range 226-8000 Hz. An overall test for difference between curves of cases and controls was calculated by multivariate analysis of variance.

RESULTS

The MD group and the subpopulations of MD patients who fulfilled the International criteria for MD showed a statistically significant lower absorbance at tympanic peak pressure compared to the control group (p < 0.001). No overlap of confidence intervals between mean curves was found within the frequency range of 2000-4000 Hz.

CONCLUSION

Absorbance measures obtained by WBT were able to distinguish between MD ears and normal ears within the frequency range of 2000-4000 Hz. The results indicate that WBT potentially could be a useful and simple non-invasive diagnostic tool for MD. However, more research on the association between absorbance measures and inner ear pathologies is needed.