Zhao Xuegen, Wilkinson Steven, Akhtar Riaz, Sherratt Michael J, Watson Rachel E B, Derby Brian
School of Materials, the University of Manchester, Manchester, M1 7HS, United Kingdom.
Mater Res Soc Symp Proc. 2011 Jan;1301. doi: 10.1557/opl.2011.572.
In this study we have established a new approach to more accurately map acoustic wave speed (which is a measure of stiffness) within soft biological tissues at micrometer length scales using scanning acoustic microscopy. By using thin (5 μm thick) histological sections of human skin and porcine cartilage, this method exploits the phase information preserved in the interference between acoustic waves reflected from the substrate surface as well as internal reflections from the acoustic lens. A stack of images were taken with the focus point of acoustic lens positioned at or above the substrate surface, and processed pixel by pixel using custom software developed with LABVIEW and IMAQ (National Instruments) to extract phase information. Scanning parameters, such as acoustic wave frequency and gate position were optimized to get reasonable phase and lateral resolution. The contribution from substrate inclination or uneven scanning surface was removed prior to further processing. The wave attenuation was also obtained from these images.
在本研究中，我们建立了一种新方法，利用扫描声学显微镜在微米长度尺度上更精确地绘制软生物组织内的声波速度（一种硬度测量指标）。通过使用人类皮肤和猪软骨的薄（5μm厚）组织切片，该方法利用了从基底表面反射的声波以及声学透镜内部反射之间干涉中保留的相位信息。将声学透镜的焦点定位在基底表面或其上方，拍摄一系列图像，并使用用LABVIEW和IMAQ（美国国家仪器公司）开发的定制软件逐像素处理，以提取相位信息。优化了诸如声波频率和门位置等扫描参数，以获得合理的相位和横向分辨率。在进一步处理之前，消除了基底倾斜或扫描表面不平的影响。还从这些图像中获得了波衰减。
