V.N.Oliynik Features of the "tissue" sound propagation channel in human thorax |
Acoustic bulletin, Vol. 3 ¹ 4, (2000) |
| The acoustic propagation through biological tissues of a thorax with allowance for availability of its rib hull and surface soft tissues is investigated. The estimations of density, sound speed and the attenuation coefficient in parenchyma of lung and soft biotissues are obtained. Within the approaches of linear acoustics the mathematical model is developed permitting to assess quantitatively a performance of the sound transmission from lung to a surface of human body. It is shown that at an acoustic propagation in the system a piston mode dominates. It is established that when the breath sounds propagate in a thorax the influence of a rib grating is exhibited in a constant padding loss of signal. It is shown that the low-frequency domain of spectrum of normal respiratory sounds is formed by sources disposed on all bulk of the lung. The high frequency portion of the spectrum is formed predominantly by sources disposed on lung's peripherals. |
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KEY WORDS: thorax, tissue, lung parenchyma, sound speed, attenuation |
| TEXT LANGUAGE: Russian |