MICROWAVE IMAGING FOR THERAPY MONITORING AND ASSESSMENT

开发低成本的成像模式用于局部癌症治疗监测和评估，这将有助于改善临床结果。支持该项目的主要假设是，近场微波成像可以提供新形式的中等分辨率（厘米尺度）空间信息，这将对治疗环境中的临床决策产生积极影响。鉴于组织中微波成像的复杂性，验证这一假设是一项长期的工作，这既需要开发可行的微波成像方法，也需要积累有关微波技术可以恢复的信息价值的实验证据。我们的研究计划不仅关注关键技术的发展，而且还寻求在受控条件下建立体内微波成像性能的极限。我们提出的技术进步的中心主题有两个：(1)在实验室规模上开发3D成像方法；(2)实现不依赖于盐水浴浸泡的高质量成像能力。我们实验工作的主要重点是在一系列体内动物研究中部署我们现有的二维成像方法，在这些研究中，我们研究了(i)治疗温度升高的微波成像，（ii）热诱导病变和（iii）辐射诱导的组织反应。在拟议的项目期间将实现的具体目标是：(1)开发了基于接收单元固定阵列机械平移和有限角度旋转的三维数据采集硬件；(2)开发了一套三维图像重建算法，其中包括双网格和总变差最小化二维图像增强方法的三维模拟；(3)利用日益复杂的临床前实验室研究对三维微波成像进行评估和优化，特别关注改进数据校准和最大化数据模型匹配；(4)利用动物模型系统对二维体内成像进行实验评估，探索微波成像治疗温度升高、热致病变和辐射诱导的组织反应；(5)改进和优化无需盐水浴浸泡成像的固体材料阵列外壳。如果成功，这项工作将大大推进目前最先进的医学微波成像技术，为未来临床规模的研究铺平道路。

There are significant opportunities for developing low cost imaging modalities for localized cancer therapy monitoring and 2assessment which could serve to improve clinical outcomes. The principal hypothesis which underpins this project is that near-field microwave imaging can provide new forms of moderately-resolved (cm-scale) spatial information that will positively influence clinical decision making in the therapy setting. Testing this hypothesis is a long term commitment given the complexities associated with microwave imaging in tissues which requires both the development of a viable microwave imaging methodology and the accumulation of experimental evidence on the value of the information that can be recovered with microwave techniques. Our research plan not only focuses on critical technology developments but also seeks to establish the limits of microwave imaging performance in vivo under controlled conditions. The central themes of our proposed technology advances are twofold: (1) to develop 3D imaging methods at the laboratory scale and (2) to realize high quality imaging capabilities not dependent on saline bath immersion. The primary focus of our experimental effort is to deploy our existing 2D imaging approach in a series of in vivo animal studies where we investigate microwave imaging of (i) therapeutic temperature elevation, (ii) thermally-induced lesions and (iii) radiation- induced tissue reactions. The specific aims that will be pursued during the proposed project period are: (1) development of three-dimensional data acquisition hardware based on mechanical translation and limited-angle rotation of fixed arrays of transceiving elements, (2) development of a suite of three- dimensional image reconstruction algorithms which include the 3D analogs of the 2D image enhancement methods of dual meshing and total variation minimization, (3) evaluation and optimization of 3D microwave imaging using preclinical laboratory studies of increasing complexity with particular attention on improving data calibration and maximizing data-model match, (4) experimental evaluation of 2D imaging in vivo using animal model systems to explore microwave imaging of therapeutic temperature elevation, thermally-induced lesions and radiation-induced tissue reactions, and (5) refinement and optimization of solid-material array housings for imaging without saline bath immersion. If successful this work would substantially advance the current state-of-the-art in medical microwave imaging technology paving the way for future studies at the clinical scale.