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肿瘤模型的异种缺氧微环境。为了实现这些目标，我们将评估一种新的光声CT扫描仪，该扫描仪利用了最近开发的相位对比磁共振血管造影（MRA）和动态对比增强MRA （DCE-MRA）的加速技术，可以显着提高时间分辨率，而不会牺牲信号噪声或空间分辨率。在第一阶段，我们将设计、构建和评估一种新的PCT扫描仪，该扫描仪将获得均匀分布在半球表面的128个“投影”的稀疏集。我们的目标是为动态研究实现亚秒级的时间分辨率，并在直径20毫米的成像体积内，在短短1.6秒内获得16个波长的光谱数据。如果我们取得成功，我们将把这些技术应用于二期癌症小鼠模型的体内。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，使研究人员能够在临床前使用近红外辐射来询问疾病的分子结构并评估对治疗的反应。该装置将使研究人员能够量化血红蛋白浓度、血流、组织氧合以及小动物靶组织中分子探针的积累，具有出色的三维空间和时间分辨率。

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.