“Physiological” Ear Clicking: Its Origin and Potential Usability as a Test Tool for the Eustachian Tube Function

Sound and Noise Sources in Sonotubometry: An Investigation of Eustachian Tube Assessment

This research aims to enhance the understanding of the acoustic processes occurring during sonotubometry, a method used to assess the Eustachian tube (ET) function. Recent advancements in digital signal processing enable a more comprehensive data analysis. In this project, a silicone model of the ET was developed to systematically study the existing noise and sound sources. These measurements were then compared with recordings from human subjects. Three distinct 'noise sources' were identified, which can influence the assessment of the ET opening using transmission measurements of the imposed signal: sound leakage from the speaker, a clicking noise at the initiation of ET opening, and rumbling/swallowing noise. Through spectral analysis, it was also possible to ascertain the spectral and temporal occurrence of these sound and noise types. The silicone model exhibited remarkable similarity to the healthy human ET, making it a robust experimental model for investigating the acoustics of sonotubometry. The findings underscore the significance of delving deeper into the analysed sound, as the noise occurring during sonotubometry can be easily misconstrued as an actual ET opening. Particularly, careful consideration is warranted when evaluating data involving clicking and swallowing noise.

An Accurate Fiducial Marker for Aligning EMG signals with Swallow Onset. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2023;2023:1-4. [PMID: 38082870 DOI: 10.1109/embc40787.2023.10340093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Swallowing involves the precise coordination of a large number of muscles. This coordination can be quantified non-invasively by electromyographic (EMG) time-series analysis of swallowing events. The temporal alignment of swallow events is critical for defining coordination patterns. Here, a new framework was developed to use the acoustic signal associated with the opening of the Eustachian tube as a fiducial marker to align EMG signals with swallowing. To investigate its accuracy, manometry, audio from the Eustachian tube, and EMG were simultaneously recorded from two participants while performing different swallowing maneuvers. Eustachian tube opening consistently occurred alongside EMG activations and within 0.025 ± 0.022 s of the gold standard manometry-determined functional swallowing onset. A comparison with two traditional EMG alignment methods based on the integrated and rectified EMG signals was then performed over eight participants. Discrepancies of between 0.2 to 0.3 s were found between the initiation of swallowing and the onset or peak EMG activity. Eustachian tube opening served as a more accurate fiducial marker for temporal data alignment, compared to the traditional EMG alignment methods that were based on EMG parameters.Clinical Relevance- The proposed method will allow EMG recordings to be directly associated with the functional onset of swallowing. This provides a more accurate foundation for time-series analysis of muscle coordination and thus the identification of EMG biomarkers associated with healthy and dysphagic swallowing.

[Prospects for a passive acoustic research method in otorhinolaryngology]

The authors of the article reviewed acoustic research methods in otorhinolaryngology. All acoustic diagnostic methods are divided into active and passive. Active acoustic methods are based on the emission of acoustic vibrations, in some cases with the subsequent reception and processing of reflected vibrations. Passive acoustic research methods are based on the recording and analysis of sounds arising during the physiological functioning of the studied organs and systems. In otorhinolaryngology, active acoustic methods of studying the ENT organ are more widespread: audiometry, acoustic impedance measurement, ultrasound examination of hearing, auditory evoked potentials, sonotubometry, acoustic rhinometry, ultrasound examination of soft tissues of the neck and paranasal sinuses. Among passive acoustic research methods, the greatest development in clinical practice in otorhinolaryngology was obtained by computer acoustic analysis of the voice - an assessment of the phonatory function of the larynx. Using similar technologies, a technique for acoustic analysis of nasal breathing was developed - a functional assessment of the external nasal valve. Separate groups of authors have carried out an experimental study of the sounds that occur when the auditory tube is opened. Achievements in acoustics and the introduction of advanced technologies in medicine create prerequisites for improving existing and developing new methods of acoustic analysis of the work of ENT organs.