POLARIZED LIGHT PROPAGATION AND IMAGING IN TISSUE

描述(改编自申请人摘要)：申请人提出 开发一种偏振光敏成像系统，可用于检测 嵌入在高散射介质中的对象(例如，肿瘤)(例如，健康 组织)。该系统将使用偏振光来区分组织和 不同的形态和偏振特性。申请者的科学研究 人们感兴趣的是组织对偏振的影响。许多调查人员都有 研究了偏振光在由球形、稀薄的模体中的传输 散布者。然而，调查对象复杂、形状不规则、密度大 在组织中发现的散射体缺乏。对根本问题的理解 生物散射体如何使光去偏振背后的物理原理对设计至关重要 以及构建用于通过组织成像的旋光仪。申请者 报告说，他们进行了初步实验，表明 被检测光的偏振态可以与非均质性相关联 在样本中。申请者提议在以下时间继续他们的科学工作 进行一系列假设驱动的实验，将产生足够的 本项目工程阶段的数据：规格、设计和 偏振光成像系统的构建。因此，他们提出了 1)建立多光谱、测角的斯托克斯偏振仪 并用于量化偏振光在不同组织中的传播和 2)偏振分辨和时间域法将 为了提高我们对组织极化的理解 特性，并进一步提高我们的测角旋光仪的灵敏度；3) 嵌入体模和体外组织中的离散结构将被成像；4) 偏振光传输的偏振敏感蒙特卡罗模型 将反复使用混浊介质来指导实验和 仪器开发；以及5)将指定成像偏振仪以 在小鼠癌症模型中区分正常和癌变组织。在 在这项工作结束后，申请者预计能够提出 一种用于小动物成像的系统的构建和测试 用于检测嵌入健康组织的肿瘤的临床前试验。

DESCRIPTION (Adapted from Applicant's Abstract): The applicants propose to develop a polarized-light-sensitive imaging system that can be used to detect objects (e.g., tumors) embedded in a highly scattering media (e.g., healthy tissue). The system will use polarized light to discriminate tissues with differing morphologic and polarization properties. The applicants' scientific interest is the effect of tissue on polarization. Many investigators have studied polarized light propagation in phantoms consisting of spherical, dilute scatterers. However, the investigation of the complex, irregular-shaped, dense scatterers found in tissue is lacking. An understanding of the fundamental physics behind how biologic scatterers depolarize light is vital to the design and construction of a polarimeter for imaging through tissue. The applicants reported having conducted preliminary experiments that indicate that changes in the polarization state of detected light can be correlated with heterogeneities in the sample. The applicants propose to continue their scientific work by conducting a series of hypothesis-driven experiments that will yield sufficient data for the engineering phase of this project: the specification, design and construction of a polarized-light imaging system. Thus, they propose the following: 1) A multi-spectral, goniometric Stokes polarimeter will be built and used to quantify polarized light propagation in different tissues and phantoms; 2) Polarization discrimination and time-domain methods will be combined in order to improve our understanding of tissue polarization properties and to add further sensitivity to our goniometric polarimeter; 3) Discrete structures embedded in phantoms and ex vivo tissue will be imaged; 4) A polarization-sensitive Monte Carlo model of polarized light propagation in turbid media will be used iteratively to guide the experiments and instrumentation development; and 5) An imaging polarimeter will be specified to discriminate normal from cancerous tissue in mouse cancer models. At the conclusion of this work, the applicants anticipate being able to propose the construction and testing of a system for use in small animal imaging and pre-clinical trials for detection of tumors embedded in healthy tissue.