Very Low Frequency EPR Imaging in Vivo Phisiology P41 EB02034

高分辨率的分子氧合图像可以为癌症治疗的传递和监测提供重要的指导。氧的EPR成像（EPRI）提供了空间分辨率、氧分辨率和组织深度均匀灵敏度的独特组合。本中心专注于优化体内EPRI氧成像预测人体图像。它是芝加哥大学、马里兰大学和丹佛大学之间的一个联盟。成功的图像需要协调开发仪器来获取图像，旋转探针来采样和报告组织液环境，以及成像策略来优化采样和分析所获得的信息。该中心建立在工程师、生物学家、放射肿瘤学家、医学物理学家、物理和有机化学家、统计学家和成像数学家的多学科努力的基础上。在过去的两年半时间里，中心1)逐点验证了EPRI氧图像，2)发展了氧与解剖学和其他生理学的共同配准，3)增加了动物肿瘤成像的大小，4)产生了第一个电子自旋回波氧图像，比连续波（CW）采集快了近一个数量级，5)开发了能够体合成的窄线三烷基自旋探针来源。6)合成持久的细胞内氮氧化物；7)从根本上改变了投影的图像重建，允许在偶数维度上进行部分投影。这些成果直接提高了空间、氧合和/或时间图像分辨率。生理学相关的分辨率目标要求提高小动物EPRI氧图像的分辨率。这种改进对于更大规模的组织和肿瘤成像是必要的。我们建议：1)实现多种连续波采集技术以提高投影采集率，选择感兴趣的区域并构建新型谐振器；2)对于脉冲图像采集，增加带宽和带宽均匀性，以及新型谐振器和技术来选择感兴趣的区域；3)开发新颖的，甚至更窄的线自旋探针，具有更高的氧灵敏度；4)建立在图像采集和分析进展的基础上。我们希望在第五年的支持中获得一个人的形象。

High resolution images of molecular oxygenation images can provide crucial guides to the delivery and monitoring of cancer therapy. EPR imaging (EPRI) of oxygen provides a unique combination of spatial resolution, oxygen resolution, and uniform sensitivity with depth in tissue. This Center focuses on the optimization of In Vivo EPRI oxygen imaging anticipating human images. It is a consortium between the Universities of Chicago, Maryland and Denver. Successful images require coordinated development of instrumentation to obtain the images, spin probes to sample and report the tissue fluid environment and imaging strategies to optimally sample and analyze the information obtained. The Center is built on multidisciplinary effort from engineers, biologists, radiation oncologists, medical physicists, physical and organic chemists, statisticians and imaging mathematicians. In the past 21/2 years the Center 1) validated EPRI oxygen images point by point, 2) developed co-registration of oxygen with anatomy and other physiology, 3) increased animal tumor size imaged, 4) produced the first electron spin echo oxygen image nearly an order of magnitude faster than continuous wave (CW) acquisition, 5) developed a source of narrow line trityl spin probe capable of bulk synthesis, 6) synthesized persistent intracellular nitroxides and 7) radically altered reconstruction of images from projections allowing partial projections in even dimensions. These achievements directly improve spatial, oxygenation and/or temporal image resolution. Physiologically relevant resolution goals mandates improvement in resolution of EPRI oxygen images for small animals. This improvement will be necessary to scale to imaging larger volumes of tissue and tumor. We propose to: 1) Implement multiple techniques for CW acquisition to increase projection acquisition rate, select regions of interest and construct novel resonators 2) For pulsed image acquisition increase bandwidth and bandwidth uniformity as well as novel resonators and techniques to select regions of interest 3) Develop novel, even narrower line spin probes to with higher oxygen sensitivity 4) Build on the image acquisition and analysis progress. We hope to acquire a human image in the 5th year of support.