Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
Ultrasonics. 2011 Apr;51(3):289-95. doi: 10.1016/j.ultras.2010.09.005. Epub 2010 Oct 23.
Lung diseases, such as acute respiratory distress syndrome (ARDS) and idiopathic pulmonary fibrosis (IPF), are closely associated with altered lung elastic properties. Pulmonary function testing and imaging are routinely performed for evaluating lung diseases. However, lung compliance, a measure of lung elastic properties, is rarely used in clinic, because it is invasive and provides only a global and arguably biased estimate of lung elastic properties. Current ultrasound methods also cannot be used for imaging lungs because ultrasound cannot penetrate the lung tissue. In this paper, an ultrasound image guided and surface wave based method is proposed to measure regional lung surface wave speed and estimate lung elasticity noninvasively. The method described here was not explored before to the best knowledge of the authors. Experiments in an ex vivo pig lung and an in vivo human lung pilot study are reported. The surface wave speed is measured to be 1.83±0.02m/s at 100Hz by ultrasound for the ex vivo pig lung at 3mmHg pressure, which is validated by an optical measurement. An in vivo human lung pilot experiment measures the surface wave speed to be 2.41±0.33m/s for the 100Hz sinusoidal wave at total lung capacity (TLC) and 0.99±0.09m/s at functional residual capacity (FRC). These values of wave speed fall well within the range of available literature.
肺部疾病，如急性呼吸窘迫综合征（ARDS）和特发性肺纤维化（IPF），与肺部弹性特性的改变密切相关。肺功能测试和成像常用于评估肺部疾病。然而，肺顺应性（衡量肺部弹性特性的指标）在临床上很少使用，因为它是侵入性的，并且只能提供肺部弹性特性的全局和有争议的估计。目前的超声方法也不能用于肺部成像，因为超声不能穿透肺组织。在本文中，提出了一种基于超声图像引导和表面波的方法，以无创方式测量区域肺表面波速度并估计肺弹性。据作者所知，这里描述的方法以前没有被探索过。报告了在离体猪肺和体内人肺初步研究中的实验。在 3mmHg 压力下，离体猪肺的表面波速度在 100Hz 时通过超声测量为 1.83±0.02m/s，通过光学测量进行了验证。在体内人肺初步实验中，测量到在总肺容量（TLC）时，100Hz 正弦波的表面波速度为 2.41±0.33m/s，在功能残气量（FRC）时为 0.99±0.09m/s。这些波速值在现有文献的范围内。
