Acoustic characterisation of thoracic body tissues in the audible frequency range
- 46 Downloads
A previous study by Jones and Thomas  suggests that data relating to the physiological condition within the thoracic cavity may be obtainable utilising low frequency acoustic signals applied to the mouth and detected on the chest wall. In order to evaluate the contribution to the mouth to chest wall frequency response of the separate elements within the thorax, and to estimate the effect on this response when the lung physiology changes, an acoustic model of the thorax is required. To aid the development of this model, experiments have been carried out in order to establish the frequency dependence of the acoustic attenuation and speed of propagation through thoracic tissue samples in the audible frequency range 20–500 Hz. Samples from the porcine family were used due to their physical similarity to those of humans and their being obtainable within a short time of death.
The results of this work can be utilised in the development of an acoustic model of the human thorax, this in turn enabling simulation and analysis of low frequency acoustic transmission from the trachea to the chest wall.
Key wordsacoustic tissue speed of sound attenuation thorax lung
Unable to display preview. Download preview PDF.
- 1.McCredie, R.M.: Measurement of pulmonary edema in valvular heart disease,Circulation 36 (1967), 381–386.Google Scholar
- 2.Jones, M.P. and Thomas, D.W.: Acoustic detection of physiological change within the thorax,International Conference of Acoustic Sensing and Imaging, IEE, London, 1993, 201–205.Google Scholar
- 3.Cohen, A. and Berstein, A.D.: Acoustic transmission of the respiratory system using speech stimulation,IEEE Trans Biomed. Eng. 38 (1991), 126–132.Google Scholar
- 4.Wodicka, G.R. and Shannon, D.C.: Transfer function of sound transmission in subglottal human respiratory system at low frequencies,J. Appl. Physiol. 69(6) (1990), 2126–2130.Google Scholar
- 5.Wodicika, G.R., Stevens, K.N. and Shannon, D.C.: A theoretical model of sound transmission in the thorax,Proceedings of the IEEE Engineering in Medicine & Biological Society 11th Conf. 1 (1989), 248–249.Google Scholar
- 6.Kraman, S.S. and Bohadana, A.B.: Transmission to the chest of sound introduced at the mouth,J. Appl. Physiol. 66(1) (1989), 278–281.Google Scholar
- 7.Bohadana, A.B. and Kraman, S.S.: Transmission of sound generated by sternal percussion,J. Appl. Physiol. 66(1) (1989), 273–278.Google Scholar
- 8.Rice, D.A.: Sound speed in pulmonary parenchyma,J. Appl. Physiol. 54 (1983), 304–308.Google Scholar
- 9.Atochem Sensors Inc., Product Data Sheet. No 9(1989).Google Scholar