Shear Wave Reciprocity for Breast Imaging

摘要： 我们提出了一种新的超声成像方法，我们称之为剪切波互易成像（SRI）， 根据声速和组织的衰减产生图像。这些声学特性携带 重要的诊断信息，但在传统的B模式图像中除了伪影之外没有显示。为 例如，在乳房成像中，“后特征”（阴影/增强）BiRADS描述符取决于 这些财产。与传统的B模式成像形成对比，传统的B模式成像产生在图像中的变化的散斑图像。 组织声阻抗，我们提出SRI作为衰减/声音的无斑点成像方法 速度参数SRI图像与B模式和弹性成像图像互补，但产生的图像 使用与常规超声相同的反向散射成像几何形状。SRI依赖于以下原则 机械互易性，以测量声辐射力的局部变化，其涉及衰减和 声速当使用类似于ARFI成像的声辐射力脉冲时，SRI被设计为 对弹性性质不敏感，并且特别地对衰减/声速参数成像。的目的 本计画将在线阵成像系统上实现SRI，并测试其灵敏度与分辨率 通过活组织检查前的体内测量，并在来自乳房切除术的离体乳房组织中验证SRI。我们 预计SRI提供的额外信息将最终改善病变分类， 通过替换B模式中病变衰减的定性估计值所需的活检次数 用参数声学图像进行阴影化。

Abstract: We propose a new ultrasound image formation method, which we call shear-wave reciprocity imaging (SRI), to produce images based on the sound speed and attenuation of tissue. These acoustic properties carry important diagnostic information but are not revealed in conventional B-mode images except as artifacts. For example, in breast imaging the “posterior features” (shadowing/enhancement) BiRADS descriptor depends on these properties. In contrast to conventional B-mode imaging that produces speckle images of variations in tissue acoustic impedance, we propose SRI as a method for speckle-free imaging of an attenuation/sound speed parameter. SRI images are complementary to both B-mode and elastography images yet are produced using the same backscatter imaging geometry as conventional ultrasound. SRI relies on the principle of mechanical reciprocity to measure local variations in acoustic radiation force, which relate to attenuation and sound speed. While using acoustic radiation force impulses similar to ARFI imaging, SRI is designed to be insensitive to elastic properties and to specifically image the attenuation/sound speed parameter. The aims of this project are to implement SRI on a linear-array imaging system, characterize its sensitivity and resolution through in vivo measurements prior to biopsy, and validate SRI in ex vivo breast tissue from mastectomy. We expect that the additional information provided by SRI will ultimately improve lesion categorization and reduce the number of biopsies required by replacing qualitative estimates of lesion attenuation from B-mode shadowing with parametric acoustic images.