ACCURATE IN VIVO ULTRASONIC SCATTERING ASSESSMENTS

准确的体内超声波散射评估

• 批准号: 3177996
• 负责人: JAMES A. ZAGZEBSKI
• 金额: $ 11.05万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-09-01 至 1993-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3177996
• 关键词: adipocytes; clinical biomedical equipment; human subject; image processing; kidney imaging /visualization; kidney transplantation; liver disorder diagnosis; muscle cells; phantom model; radiobiology; tissues; ultrasonography; ultrasound biological effect

Our objectives are to determine the intrinsic ultrasonic scattering properties of human soft tissues and to produce phantoms which have scattering identical to organs imaged with diagnostic ultrasound. Since phantom materials already exist which have speeds of sound, density and ultrasonic attenuation matched to soft tissue parenchyma, the matching scatter will result in tissue equivalent phantoms. These would be extremely useful for performance evaluation of clinical instruments, for developing ultrasonic tissue characterization techniques and for studying mechanisms underlying the generation of scattered echo signals and production of image details on clinical scans. Backscatter from large volume samples will be studied, analogous to similar work carried out by other investigators. In addition, apparatus has been developed for measuring the differential scattering cross section per unit volume. The latter technique allows the scatter as a function of angle to be quantitatively determined for frequencies throughout the diagnostic range. Measurements from volumetric scattering standards will be used to verify that the measurement process provides instrument independent (intrinsic) scatter values. The differential scatter cross section will be measured for normal human liver, fat, muscle and brain tissue. Comparisons will be made between in vivo measurements and in vitro measurements of ultrasonic backscattering for organs in large laboratory animals. Tissue equivalent phantoms will be developed using newly developed materials, combining mixtures of small particle and intermediate size scatterers. Water based gels used in this project will allow an iterative approach to the problem of matching scatter. The role of scatter on clinical ultrasound images will be investigated by studying the generation of echo signals and gray scale texture in phantoms. Texture analysis studies will account for the intrinsic scatter properties of the phantom as well as the temporal and spatial transducer characteristics and other components of the imaging chain.

我们的目标是确定固有的超声波散射 人体软组织的特性并产生具有 散射与诊断超声成像的器官相同。 自从 幻影材料已经存在，具有声速、密度和 超声衰减与软组织实质相匹配，匹配 散射将导致组织等效模型。 这些将是极其 可用于临床仪器的性能评估、开发 超声组织表征技术和研究机制 散射回波信号生成和图像生成的基础 临床扫描的详细信息。 大体积样品的反向散射将 研究，类似于其他研究人员进行的类似工作。 在 此外，还开发了用于测量差异的装置 单位体积的散射截面。 后一种技术允许 散射作为角度的函数来定量确定 整个诊断范围内的频率。 体积测量 散射标准将用于验证测量过程 提供仪器独立（固有）散射值。 这 将测量正常人肝脏的微分散射截面， 脂肪、肌肉和脑组织。 将在体内进行比较 超声波反向散射的测量和体外测量 大型实验动物的器官。 组织等效模型将是 使用新开发的材料开发，结合​​小 颗粒和中等尺寸的散射体。 此中使用的水基凝胶 项目将允许采用迭代方法来解决匹配问题 分散。 散射对临床超声图像的作用将是 通过研究回波信号和灰度的生成进行研究 幻象中的纹理。 纹理分析研究将解释 体模的固有散射特性以及时间和时间 空间换能器特性和成像的其他组成部分 链。