Ozer M B, Acikgoz S, Royston T J, Mansy H A, Sandler R H
Baxter Healthcare Corporation, Deerfield, Illinois 60015, USA.
J Acoust Soc Am. 2007 Jul;122(1):657-61. doi: 10.1121/1.2715453.
An acoustic boundary element (BE) model is used to simulate sound propagation in the lung parenchyma. It is computationally validated and then compared with experimental studies on lung phantom models. Parametric studies quantify the effect of different model parameters on the resulting acoustic field within the lung phantoms. The BE model is then coupled with a source localization algorithm to predict the position of an acoustic source within the phantom. Experimental studies validate the BE-based source localization algorithm and show that the same algorithm does not perform as well if the BE simulation is replaced with a free field assumption that neglects reflections and standing wave patterns created within the finite-size lung phantom. The BE model and source localization procedure are then applied to actual lung geometry taken from the National Library of Medicine's Visible Human Project. These numerical studies are in agreement with the studies on simpler geometry in that use of a BE model in place of the free field assumption alters the predicted acoustic field and source localization results. This work is relevant to the development of advanced auscultatory techniques that utilize multiple noninvasive sensors to construct acoustic images of sound generation and transmission to identify pathologies.
声学边界元（BE）模型用于模拟肺实质中的声音传播。该模型经过计算验证，然后与肺模型的实验研究进行比较。参数研究量化了不同模型参数对肺模型内产生的声场的影响。然后将BE模型与源定位算法相结合，以预测模型内声源的位置。实验研究验证了基于BE的源定位算法，并表明如果用忽略有限尺寸肺模型内产生的反射和驻波模式的自由场假设代替BE模拟，相同的算法效果不佳。然后将BE模型和源定位程序应用于取自美国国立医学图书馆可视人项目的实际肺几何结构。这些数值研究与对更简单几何结构的研究一致，即使用BE模型代替自由场假设会改变预测的声场和源定位结果。这项工作与先进听诊技术的发展相关，该技术利用多个非侵入性传感器构建声音产生和传播的声学图像以识别病变。
