Evaluation of Progression of Arteriosclerosis by the Quantitative Assessment of Acoustic Tissue Characteristics Using Acoustic Microscopy

对动脉硬化进行定量评价是非常重要的。本研究利用声学显微镜测量了人冠状动脉内膜的超声衰减和传播速度，旨在通过测量超声衰减和传播速度来阐明动脉硬化活体组织的声学特性，并通过这些指标来评价动脉硬化的进展。我们使用了超声组织定征系统与扫描声学显微镜（HSAM-500 S，450 MHz）。从52名患者的尸检中获得冠状动脉标本，并切成4微米厚。根据光镜下内膜的病理改变，将其分为正常组（21例）、硬化早期组（24例）和硬化晚期组（7例），年龄与超声衰减、传播速度的关系无统计学意义 关于我们 意义重大。值得注意的是，超声衰减在早期较低（1.7（±）SY. ±-晚期高于晚期（5.4 ± 0.6dB）结果：（1）正常组（2.5 ± 0.8dB）较正常组（2.5 ± 0.8dB）明显增高早期传播速度较慢（1611.9 ± 0.5dB [] 53.0m/s），后期更快（2031.4（]SY. ±- 145.0m/s）比正常值（1757.8（±）SY. [）90.4）。综上所述，超声衰减和传播速度均不受年龄的显著影响，而主要受病理性动脉粥样硬化病变的影响。此外，与冠状动脉的光学结果相比，这两个参数均显示出非线性变化。因为传播速度与体积模量的平方根成比例，所以传播速度在较硬的组织中更快。因此，我们得出结论，冠状动脉内膜在光学定义的疾病的早期阶段表现出一个初始软化相比，正常组织，这是其次是增加硬化的进展阶段，作为一个渐进的纤维化和钙化的结果。少

It is very important to evaluate arteriosclerosis quantitatively. The aim of this study is to elucidate acoustic characteristics of living tissue in arteriosclerosis by measuring the ultrasonic attenuation and propagation velocity with a scanning acoustic microscopy, and to evaluate the progression of arteriosclerosis by these indices.We measured ultrasonic attenuation and propagation velocity in the human coronary artery intima using acoustic microscopy. We used an ultrasonic tissue characterization system with a scanning acoustic microscopy (HSAM-500S,450MHz). Coronary artery specimens were obtained by autopsy from 52 patients and cut into 4 microns thick. Based on the pathological findings in the intima with an optical microscope, we classified them into 3 groups : normal (21specimens), early stages of sclerosis (24 specimens), and advanced stages of sclerosis (7 specimens).The relationships between age and ultrasonic attenuation, and age and propagation velocity were not statistica … More lly significant. Significantly, ultrasonic attenuation was lower in the early stage (1.7(]SY.+-[)0.6dB), and higher in the advanced stage (5.4(]SY.+-[)0.8dB) than in normal (2.5(]SY.+-[)0.5dB), while propagation velocity was slower in the early stage (1611.9(]SY.+-[)53.0m/s), and faster in the advanced stage (2031.4(]SY.+-[)145.0m/s) than in normal (1757.8(]SY.+-[)90.4).In summary, both ultrasonic attenuation and propagation velocity were not significantly affected by age, but were mainly influenced by pathological atherosclerotic change. In addition, both parameters showed non-linear change as compared with the optical findings of coronary arteries. Because propagation velocity is proportional to the square root of the bulk modulus, Propagation velocity is faster in harder tissue. We therefore concluded that coronary artery intima in optically defined early stages of disease showed an initial softening as compared with normal tissue, and this was followed by increasing hardening in the advanced stage as a result of porgressing fibrosis and calcification. Less