Microwave Spectroscopy and Imaging

微波光谱和成像

• 批准号: 6493958
• 负责人: PAUL M MEANEY
• 金额: $ 16.87万
• 依托单位: DARTMOUTH COLLEGE
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-28 至 2002-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6493958
• 关键词: bioimaging /biomedical imaging; biomedical equipment development; breast neoplasm /cancer diagnosis; breast neoplasms; clinical research; computer program /software; computer system hardware; diagnosis design /evaluation; digital imaging; electromagnetic radiation; female; human subject; human tissue; image enhancement; mammography; microwave spectrometry; neoplastic process; women's health

Tissue sample data suggests that malignant mammary tumors have electrical properties which mimic those typically found in high-water content tissues such as muscle whereas the surrounding normal breast is more representative of low-water content fatty tissues. Presumably, the increased blood volume associated with the neovascularization in the rapidly proliferating tumor periphery is partly responsible for the increased water content which establishes a significant contrast mechanism to which microwave illumination is particularly sensitive. It has also been hypothesized that the progressive replacement of fat lobules with fibroblastic proliferation and epithelial cells and the alterations that occur at transformed cell surfaces produce ultrastructural changes in neoplastic breast tissue which cause the observed difference in electrical properties. In fact, the normal and malignant human tissues of the same histological type, the largest difference in electrical properties. In fact, for normal and malignant human tissues of the same histological type, the largest difference in electrical properties has been observed in the mammary gland relative to colon, kidney, liver, lung and muscle. This data coupled with recent advances in model-based near-field imaging concepts provide a compelling rationale to pursue microwave imaging of breast tissue for diagnostic-advantage. Project III will extent previously developed near-field microwave imaging principles and concepts of high frequency (0.5-3 GHz) electromagnetic interrogation of breast tissue for the purpose of generating spatially-resolved electrical property distributions The increase in operating frequency range can readily occur because of the largely translucent nature of breast tissue to microwave illumination and the overall small physical dimensions of the imaging region of interest. However, changing the operating frequency range drives both hardware and software design considerations which are the focus of the developmental components of this project. The specific aims of Project III can be summarized as (1) to realize a prototype 32 channel high frequency (o.5-3GHz) data acquisition system for near-field microwave illumination, (2) to implement, in conjunction with the Computational Core, new model-based image reconstruction advances including multi-component objective function minimizations, adaptive dual meshing, antenna coupling models and multi-spectral reconstructions and explore imaging method extensions, in particular,, with regard to three-dimensional imaging, (3) to evaluate and optimize phantom imaging based on geometries relevant to clinical breast examination, (4) in conjunction with the Clinical Core, demonstrate the clinical feasibility of microwave breast imaging and initiate an evaluation of the efficacy of high frequency electromagnetic property imaging as a diagnostic tool in patients with normal and abnormal mammograms

组织样本数据表明，恶性乳腺肿瘤的电学特性与肌肉等高含水量组织的电学特性相似，而周围的正常乳腺则更具有低含水量脂肪组织的代表性。据推测，在快速增殖的肿瘤周围，与新生血管形成相关的血容量增加是导致含水量增加的部分原因，这建立了微波照明特别敏感的重要对比机制。还有一种假设是，脂肪小叶逐渐被成纤维细胞增殖和上皮细胞替代，以及转化细胞表面发生的改变，会在肿瘤乳腺组织中产生超微结构变化，从而导致观察到的电学特性差异。事实上，正常和恶性的人体组织相同的组织学类型，最大的差别是电学性质。事实上，在相同组织学类型的正常和恶性人体组织中，相对于结肠、肾脏、肝脏、肺和肌肉，在乳腺中观察到的电特性差异最大。这些数据与基于模型的近场成像概念的最新进展相结合，为追求乳腺组织的微波成像诊断优势提供了令人信服的理由。项目III将扩展先前开发的近场微波成像原理和高频（0.5-3 GHz）电磁探测乳房组织的概念，以产生空间分辨的电特性分布。由于乳房组织在微波照射下大部分是半透明的性质，并且感兴趣的成像区域的整体物理尺寸很小，因此工作频率范围的增加很容易发生。然而，改变工作频率范围驱动硬件和软件设计考虑，这是该项目开发组件的重点。项目III的具体目标可以概括为：(1)实现32通道近场微波光照高频（0.5 - 3ghz）数据采集系统原型；(2)结合Computational Core实现基于模型的图像重建新进展，包括多分量目标函数最小化、自适应双网格划分、天线耦合模型和多光谱重建，探索成像方法扩展，特别是：在三维成像方面，(3)评估和优化与临床乳腺检查相关的基于几何形状的幻影成像；(4)联合临床核心，论证微波乳腺成像的临床可行性，并开始评估高频电磁特性成像作为正常和异常乳房x线检查患者诊断工具的有效性