Generation of Temperature Maps of Heated Materials using 3D Ultrasound Imaging

背景：超声（US）成像是一种廉价的技术，易于获得，并广泛用于人体成像和非破坏性检测，具有诸如结构实时成像、使用多普勒技术测量流体速度和使用多种方法测量材料弹性等能力。重要的研究正在进行中，以扩展美国成像的能力，以允许生成材料的其他方面的信息。******在过去的20年里，我们的实验室一直专注于探索和开发基于3DUS（我们是世界上这项技术的先驱之一）、机器人技术和先进的图像处理技术（如3D可视化、分割和配准）的美国引导治疗系统。为了指导治疗，我们使用了各种组织热消融技术，如射频、微波和激光，并使用磁共振成像来绘制组织温度。在本提案中，我们建议利用我们正在进行的研究，探索美国成像3D温度测绘的能力。******目的：我们的目的是从根本上研究3DUS在测量材料和组织温度变化方面的应用。具体来说，在5年的时间里，我们将追求以下目标：(1)探索可以优化3DUS的条件，以在均匀材料加热时生成3D温度图；(2)利用3DUS在动物组织中生成三维温度图；(3)将金标准温度测量和基于3duss的温度图与计算模型相关联；(4)开发3d温度测绘过程中材料运动的校正方法。******方法：美国的温度监测技术主要基于两种现象：由于材料热膨胀引起的声信号位移的量化和声速的局部变化。因此，利用在两个不同温度下获得的两个独立图像中相同位置的斑块的回波去相关，可以校准去相关度量以提供有关温差的信息。然而，利用这种方法受到材料运动和使用2D图像开发的技术的阻碍，而由于温度变化而导致的材料变化发生在3D中。因此，我们的研究计划将研究如何利用我们实验室的3DUS成像和运动补偿开发来测量3D温度变化。******新颖性和预期意义：我们的研究计划将产生关于美国测量的基础物理学的新知识，以及3DUS信号如何随温度变化而变化。我们认为，通过将3DUS信号检测与运动补偿相结合，有可能克服其他人在开发美国测温技术时面临的障碍，并为各种应用中的美国成像提供扩展能力。

BACKGROUND: Ultrasound (US) imaging is an inexpensive technique that is readily available and used extensively in human imaging and non-destructive testing, with capabilities such as real-time imaging of structure, velocity measurements of fluids using Doppler techniques, and material elasticity using a variety of approaches. Significant research is ongoing to extend the capability of US imaging to allow generation of information of other aspects of materials. ******For the past 2 decades our lab has focused on exploring and developing systems used for US-guided therapy based on 3DUS (we are among the world pioneers of this technology), robotics and advanced image processing techniques such as 3D visualization, segmentation, and registration. For therapy guidance we used various techniques for thermal ablation of tissues, such as RF, microwave and lasers, with magnetic resonance imaging to map temperature of tissue. In this proposal, we propose to leverage our ongoing research and explore the capability of US imaging for 3D temperature mapping.******OBJECTIVE: Our aim is to fundamentally investigate the use of 3DUS to measure changes in temperature in materials and tissues. Specifically, over 5 years, we will pursue our aim following these objectives: (1) explore the conditions whereby 3DUS may be optimized to generate 3D temperature maps in homogenous materials as they are heated; (2) generate 3D temperature maps using 3DUS in animal tissues; (3) correlate gold standard temperature measurements and 3DUS-based temperature maps with computational models; and (4) develop methods to correct for motion of materials during 3DUS-based temperature mapping.******APPROACH: US-based temperature monitoring techniques are primarily based on two phenomena: quantification of acoustic signal shifts due to thermal expansion of the material and local changes of the speed of sound. Thus, using echo decorrelation of patches of the same location in two separate images obtained at two different temperatures, it has been shown that the decorrelation metric can be calibrated to provide information on the temperature difference. However, exploiting this approach has been hampered by motion of the material and the fact that techniques developed used 2D images, yet changes in the material due to temperature changes occurs in 3D. Thus, our research program will investigate how to leverage 3DUS imaging and motion compensation developments in our lab to be able to measure temperature changes in 3D.******NOVELTY AND EXPECTED SIGNIFICANCE: Our research program will generate new knowledge of the fundamental physics of US measurements and how 3DUS signals change with changes in temperature. We think that by combining 3DUS signal detection with motion compensation has the potential to overcome the obstacles others have faced in developing US-based thermometry and provide extended capability for US imaging in a variety of applications.