MRI-Compatible Diffuse Optical Tomography System

兼容 MRI 的漫射光学断层扫描系统

• 批准号: 6710477
• 负责人: ANDREAS H HIELSCHER
• 金额: $ 43.99万
• 依托单位: COLUMBIA UNIV NEW YORK MORNINGSIDE
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-15 至 2006-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6710477
• 关键词: bioimaging /biomedical imaging; biomedical equipment development; image processing; laboratory rat; magnetic resonance imaging; optics; oximetry; three dimensional imaging /topography; tomography

DESCRIPTION (provided by applicant): The overall goal of this proposal is the development of a three-dimensional optical tomographic (OT) near-infrared imaging system for oximetry in small animals. The system will be designed to allow for co-registration of OT data and magnetic resonance (MR) imaging data, but may also be used as a stand-alone optical imaging unit. While commercial systems that perform optical blood-oxygenation monitoring exist, these instruments have not been optimized for small animal studies and have not been combined with MR imaging systems. Furthermore, the available devices often operate with a limited number of sources and detectors, do not generate three-dimensional volumetric images, and the image reconstruction is performed with diffusion-theory-based algorithms. It is well known, however, that diffusion theory does not fully account for the effects of light propagation in small biological media (diameter 1-2 cm), because at these dimensions the diffusion approximation to the more generally applicable theory of radiative transfer is not sufficiently accurate. The proposed work attempts to overcome the current shortfalls and develop a near-infrared optical imaging system that can be used in combination with standard small animal MR scanners. The main hypothesis of this project is that current limitations of optical tomographic imaging can be addressed by implementing a three-dimensional frequency-domain reconstruction scheme that is based on the equation of radiative transfer (ERT). This algorithm will be implemented and used in conjunction with a commercially available frequency-domain measurement system (IAMGENT from ISS, Urban-Champaign, IL), which will be adapted to collect data inside an MR small animal imager. By co-registering optical and MR data one can combine the benefits of MR's high-spatial-resolution, with OT's high temporal resolution and its capability of separating oxyhemoglobin, deoxyhemoglobin, and blood volume effects. For this project we will pursue the following three specific aims: (1) Develop and numerically validate of a three-dimensional, transport-theory-based, frequency-domain image reconstruction code for diffuse optical tomography; (2) Validate and evaluate the optical tomographic imaging system (code and instrument) in a small animal magnetic resonance imager; and (3) Compare frequency-domain and steady-state, transport-theory based optical tomography with diffusion-theory-based optical tomography. This comparison will quantify the advantages and disadvantages of these different optical imaging modalities.

描述（由申请人提供）：该提案的总体目标是开发小动物中氧仪的三维光学层析成像（OT）近红外成像系统。该系统将旨在允许共同注册OT数据和磁共振（MR）成像数据，但也可以用作独立的光学成像单元。尽管存在进行光学血氧监测的商业系统，但这些仪器尚未针对小型动物研究进行优化，尚未与MR成像系统结合使用。此外，可用的设备通常以有限数量的源和检测器运行，不会生成三维体积图像，并且图像重建是通过基于扩散理论的算法进行的。然而，众所周知，扩散理论并不能完全解释小型生物学培养基（直径1-2厘米）中光传播的影响，因为在这些维度下，对更普遍适用的辐射转移理论的扩散近似不够准确。 拟议的工作试图克服当前的短缺并开发近红外的光学成像系统，该系统可以与标准的小动物MR扫描仪结合使用。该项目的主要假设是，可以通过实现基于辐射转移方程（ERT）方程来实施光学断层成像的当前局限性。该算法将与商业上可用的频域测量系统（来自ISS，ISS，Urban-Champaign，IL）一起实施和使用，该系统将适用于在MR小动物成像仪中收集数据。通过共同注册光学数据和MR数据，一个人可以将MR高空间分辨率的好处与OT的高时间分辨率及其分离氧气血红蛋白，脱氧血红蛋白和血容量效应的能力结合在一起。对于该项目，我们将追求以下三个特定目的：（1）开发和数字验证基于三维的，基于传输理论的频率域图像重建代码，用于弥漫性光学断层扫描； （2）在小动物磁共振成像仪中验证和评估光学断层成像系统（代码和仪器）； （3）比较基于扩散理论的光学层析成像的频域和稳态，基于传输理论的光学断层扫描。此比较将量化 这些不同的光学成像方式。