HYPR-Spectral PCT for Preclinical Imaging

描述（由申请人提供）：本研究项目的长期目标是开发仪器和加速重建技术，使研究人员能够在体内测量异种移植和基因工程小鼠中生长的肿瘤模型的异质缺氧微环境。为了实现这些目标，我们将评估一种新的光声CT扫描仪，旨在利用最近开发的相位对比磁共振血管造影术（MRA）和动态对比增强MRA（DCE-MRA），可以显着提高时间分辨率，而不牺牲信噪比或空间分辨率的加速技术。在第一阶段，我们将设计，建造和评估一个新的PCT扫描仪，将获得一组稀疏的128个“投影”均匀分布在半球表面。我们的目标是实现亚秒级的时间分辨率的动态研究，并在短短的1.6秒内，在整个20毫米直径的成像体积获得超过16个波长的光谱数据。如果我们成功了，我们将在第二阶段将这些技术应用于体内癌症小鼠模型。公共卫生相关性：制药公司和学术机构的科学家经常使用小动物（特别是小鼠）的临床前成像来研究疾病进展并监测对治疗的反应。我们建议开发一种新型的光声成像设备，使研究人员能够询问疾病的分子结构，并使用近红外辐射在临床前环境中评估对治疗的反应。该设备将使研究人员能够以出色的三维空间和时间分辨率量化小动物靶组织中的血红蛋白浓度、血流、组织氧合和分子探针的积累。

DESCRIPTION (provided by applicant): The long-term objective of this research project is to develop instrumentation and accelerated reconstruction techniques that will allow researchers to measure in vivo the heterogeneous hypoxic microenvironment of tumor models grown in mice, both xenografts and genetically engineered. To achieve these goals we will evaluate a new photoacoustic CT scanner designed to take advantage of acceleration techniques recently developed for phase contrast magnetic resonance angiography (MRA) and dynamic contrast enhanced MRA (DCE-MRA), which can significantly improve temporal resolution, without sacrificing signal to noise or spatial resolution. In Phase I we will design, construct and evaluate a new PCT scanner that will acquire a sparse set of 128 "projections" uniformly distributed over the surface of a hemisphere. Our goals are to achieve sub-second temporal resolution for dynamic studies and to acquire spectroscopic data over 16 wavelengths in as little as 1.6 seconds throughout a 20-mm-diameter imaging volume. Should we succeed, we will apply these techniques in vivo to mouse models of cancer in Phase II. PUBLIC HEALTH RELEVANCE: Scientists at pharmaceutical companies and academic institutions routinely employ preclinical imaging of small animals, especially mice, to study disease progression and monitor response to therapies. We propose to develop a novel, photoacoustic-imaging device that would allow researchers to interrogate the molecular structure of disease and assess response to therapy in a preclinical setting using near infrared radiation. This device would allow researchers to quantify hemoglobin concentration, blood flow, tissue oxygenation, and the accumulation of molecular probes in targeted tissues in small animals with excellent 3-D spatial and temporal resolution.