Applications of Photon Migration to Tissue Tomography and Spectroscopy

光子迁移在组织断层扫描和光谱学中的应用

• 批准号: 6432508
• 负责人: Amir H Gandjbakhche
• 金额: --
• 依托单位: EUNICE KENNEDY SHRIVER NATIONAL INSTITUTE OF CHILD HEALTH & HUMAN DEVELOPMENT
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6432508
• 关键词: bioimaging /biomedical imaging; biomedical equipment development; fluorescent dye /probe; mathematical model; model design /development; nephelometry; noninvasive diagnosis; optics; phantom model; structural biology; time resolved data; tomography

We have continued our work on theoretical, experimental, and computational aspects of light -tissue interactions for non-invasive quantitative optical imaging and spectroscopy. Researchers at PTB of Berlin provided us time of flight measurements in transillumination geometry of breast images in two wavelengths (670 and 780nm). We have applied our methodology known as time-dependent contrast functions, to quantify the size and the optical properties of the normal tissue background and those of the tumor localized by standard mammography. We were successfully able to find the exact location, estimate the size, and retrieve the scattering and the absorption coefficients of the tumor and those of the background. Using the absorption spectra of oxy- and deoxy-hemoglobin, we were able to estimate the oxygen saturation and the total blood volume of the tumor and background tissue from the absorption coefficients at 670 and 780nm. Work is underway to study the effects of boundaries on the images. In order to avoid incisional biopsy in the oral cavity, a theoretical framework has been developed to quantify the thickening of the epithelial layer in oral mucosa non-invasively. We have developed a spectroscopic device which uses an oblique angle reflectance setting and started to be used in a Phase II clinical trial (designed by NCI) for the non-invasive study of inflammation and effects of chemopreventative drugs. The results from a patient with leukoplakia compared to that obtained from a normal subject show qualitatively the prediction of the theory. Work is underway to screen more patients and make the measurement more quantitative.We are pursuing the use of exogenous and endogenous fluorescent markers to be able to achieve specificity of the spectroscopic signatures of the tissue abnormality under investigation. In collaboration with the University of Tel-Aviv, we have been awarded a BSF grant to continue our research on practical implementation of our previously developed 3D reconstruction algorithm which localizes the position and the concentration of fluorophore masses. Our inverse algorithm will be used to find the position and the concentration of liposomes filled with fluorescent particles as a model for localized fluorescent masses in vivo.. Along these line of research, we are testing an analytical theory of photon migration to retrieve the life-time of biological analytes by using phantom experiments. We are continuing a collaboration with researchers at NCI to study the practical use of our photon migration theory in the development of a guided biopsy infrared fluorescence imaging system for sentinel node detection in breast cancer using fluorescent particles.

我们一直在为非侵入性定量光学成像和光谱法而言，在理论，实验和计算方面的理论，实验和计算方面继续进行研究。柏林PTB的研究人员为我们提供了我们在两个波长（670和780nm）的乳房图像的透射几何形状的飞行测量时间。我们已经应用了称为时间依赖性对比函数的方法，以量化正常组织背景的大小和光学特性以及通过标准乳房X线摄影定位的肿瘤的肿瘤。我们成功地找到了确切的位置，估计大小，并检索肿瘤的散射和吸收系数以及背景的吸收系数。使用氧和脱氧 - 血红蛋白的吸收光谱，我们能够从670和780nm的吸收系数中估算肿瘤饱和度和肿瘤和背景组织的总血容量。正在研究边界对图像的影响。为了避免口腔中切开活检，已经开发了一个理论框架，以量化口服粘膜中上皮层的增厚。我们已经开发了一种使用斜角反射率设置的光谱设备，并开始在II期临床试验（由NCI设计）中使用，用于非侵入性炎症研究和化学预防药物的作用。与从正常受试者获得的白细胞病患者的结果相比，该理论的预测在定性上表明。正在进行筛查更多患者并使测量更加定量的工作。我们正在使用外源和内源性荧光标记物，以便能够达到正在研究的组织异常的光谱特征的特异性。 与Tel-Aviv大学合作，我们获得了BSF赠款，以继续我们对先前开发的3D重建算法的实际实施研究，该算法将荧光团质量的位置和集中度定位出来。 我们的逆算法将用于查找含有荧光颗粒的脂质体的位置和浓度，作为体内局部荧光质量的模型。沿着这些研究线，我们正在测试光子迁移的分析理论，以通过使用Phantom实验来检索生物学分析的寿命。我们正在与NCI的研究人员进行合作，以研究我们的光子迁移理论的实际使用，以开发用于使用荧光颗粒的乳腺癌中的前哨性活检红外荧光成像系统来检测哨兵。