Hoffmeister B K, Wong A K, Verdonk E D, Wickline S A, Miller J G
Washington University, Department of Physics and School of Medicine, St. Louis, Missouri 63130.
J Acoust Soc Am. 1995 Feb;97(2):1307-13. doi: 10.1121/1.413054.
The content and organization of collagen in the cardiac interstitium may represent significant determinants of the ultrasonic scattering properties of myocardium. This study was designed to investigate the anisotropic backscattering properties of a fibrous soft tissue exhibiting an ordered arrangement of fibers similar to myocardium, but possessing a substantially greater content of collagen. Human Achilles tendon was chosen for this study because it possesses a simple unidirectional arrangement of fibers and a high content of collagen compared to normal myocardium. Integrated (frequency-averaged) backscatter was measured from ten formalin fixed samples of tendon as a function of insonifying angle relative to the fiber axis of the tissue. The samples were insonified in a water bath using a 5-MHz center frequency piezoelectric transducer. Maximum backscatter occurred for insonification perpendicular to the fibers, and minimum backscatter occurred for insonification parallel to the fibers. The mean peak to nadir variation, or magnitude of anisotropy, of integrated backscatter for the ten formalin fixed samples of tendon was 36.3 dB. This compares to 14.5 dB for formalin fixed human myocardium measured in an earlier study by our laboratory.
心脏间质中胶原蛋白的含量和组织形式可能是心肌超声散射特性的重要决定因素。本研究旨在探究一种纤维软组织的各向异性背向散射特性，该组织呈现出与心肌相似的纤维有序排列，但胶原蛋白含量显著更高。本研究选用人跟腱，因为与正常心肌相比，它具有简单的单向纤维排列且胶原蛋白含量高。从十个经福尔马林固定的跟腱样本测量积分（频率平均）背向散射，作为相对于组织纤维轴的声入射角的函数。使用中心频率为5MHz的压电换能器在水浴中对样本进行超声检查。垂直于纤维进行超声检查时出现最大背向散射，平行于纤维进行超声检查时出现最小背向散射。十个经福尔马林固定的跟腱样本的积分背向散射的平均峰谷变化或各向异性大小为36.3dB。相比之下，我们实验室早期研究中测量的福尔马林固定人心肌的这一数值为14.5dB。
