3-D Thermoacoustic Computed Tomography/Molecular Imaging

3-D 热声计算机断层扫描/分子成像

• 批准号: 6858670
• 负责人: ROBERT A KRUGER
• 金额: $ 42.88万
• 依托单位: OPTOSONICS, INC.
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-01-01 至 2006-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6858670
• 关键词: bioimaging /biomedical imaging; biomedical equipment development; computed axial tomography; computer program /software; computer system design /evaluation; cyanine; fluorescent dye /probe; laboratory mouse; molecular /cellular imaging; phantom model; three dimensional imaging /topography

DESCRIPTION (provided by applicant): We propose to develop a thermoacoustic computed tomography (TCT) scanner for localizing optical-dye-labeled molecular probes in laboratory mice in vivo. This device offers two significant improvements over fluorescence intensity measurements: 1. Fully three-dimensional images will be acquired using a single axial scan of a novel, cylindrical detector army. 2. Exogenous molecular probes, to which a cyanine dye has been attached, will be detected using a dual-wavelength imaging approach. In Phase I we intend to quantify the spatial resolution and low contrast detection limitations of a TCT device that incorporates a 128-element, cylindrical transducer array. These studies will be carried out in tissue-mimicking phantoms, and the results compared to those we have acquired using a TCT device that incorporates a conventional, linear transducer array. We will employ a dual-wavelength, differential-measurement technique for isolating two non-tumor specific carbocyanine dyes (indocyanine dye and cypate), and a tumor-specific optical imaging agent (cytate) with peak absorption at 790 nm. These probes have high extinction coefficient (> 150,000 M-1 cm-1) and low fluorescence quantum yield (<20%), characteristics that favor thermoacoustic imaging. Our goals are to: 1. achieve < 0.5-mm high-contrast, spatial resolution in three dimensions, and 2. image a dye concentration of < 100 nM with a signal-to-noise ratio (SNR) of > 5 within a 1 mm3 volume (100 fmoles) embedded in a tissue-mimicking phantom. In Phase II we will construct a prototype TCT scanner and site the device at the Optical Radiology Laboratory, Washington University, St. Louis, MO. There, researchers will utilize novel monomolecular multimodal imaging agents to compare the imaging capabilities of this TCT scanner to a commercial mu-PET scanner and conventional fluorescence intensity imaging system in a series of phantom and in vivo mouse-imaging experiments.

描述(由申请人提供)： 我们建议开发一种热声计算机断层扫描(TCT)扫描仪，用于在实验小鼠体内定位光学染料标记的分子探针。与荧光强度测量相比，该设备有两个显著的改进：1.使用一种新型的圆柱形探测器组进行一次轴向扫描，可以获得全三维图像。2.将使用双波长成像方法检测连接了花菁染料的外源分子探针。在第一阶段，我们打算量化TCT设备的空间分辨率和低对比度检测限制，该设备结合了128个元素的圆柱形换能器阵列。这些研究将在模拟组织的模体中进行，并将结果与我们使用TCT设备获得的结果进行比较，TCT设备结合了传统的线性换能器阵列。我们将使用双波长、差示测量技术来分离两种非肿瘤特异性的碳菁染料(吲哚青染料和磷酸)，以及一种肿瘤特异性的光学显像剂(胞酸盐)，其峰值吸收在790 nm。这些探测器具有高消光系数(&gt；15万M-1 cm-1)和低荧光量子产率(&lt；20%)，这些特性有利于热声成像。我们的目标是：1.实现0.5毫米的高对比度，三维空间分辨率；2.在嵌入组织模拟体模的1毫米体积(100摩尔)内，成像&lt；100纳米的染料浓度，信噪比(SNR)为&gt；5。在第二阶段，我们将建造一台TCT扫描仪原型，并将该设备安装在密苏里州圣路易斯华盛顿大学的光学放射学实验室。在那里，研究人员将利用新型单分子多模式成像剂，在一系列体模和活体小鼠成像实验中，将这种TCT扫描仪的成像能力与商业Mu-PET扫描仪和传统的荧光强度成像系统进行比较。