SUSCEPTIBILITY AND DIFFUSION CONTRAST AT HIGH MAGNETIC FIELD

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 我们感兴趣的是成像和量化小鼠大脑在高磁场下的磁化率变化所产生的对比。这项工作是基于Duyn等人的观察，即大脑的细胞结构细节在相位对比图像中可以比使用更传统的对比度量(例如T1、T2、扩散)更加明显。我们相信，这是一个从根本上实现的项目，将允许扩展到许多不同的领域。该项目有几个不同的阶段： 第一阶段：我们将根据之前在卢卡斯中心(斯坦福)所做的工作，建立相衬成像的方法。这将包括测量和校正7T MR系统中的Bo不均匀性，以及测量和校正M2M 35 mm正交线圈的B1不均匀性。 第二阶段：我们将在100微米的空间分辨率下，使用位相对比方法的3D实现对活的C57BL/6J小鼠进行成像。我们将把大脑特定区域的对比度与更传统的成像方案(SPGR、FSE和Fiesta)进行比较。 阶段3：我们将把该方法输出到9.4T系统，以允许在21微米处进行脑灌注固定的成像，其中活性染料(ProHance)的分布可能提供更显著的相位对比度。 阶段4：我们将期待最初在模体中检测到小浓度SPIO造影剂的可能性，以确定分子成像的潜在灵敏度增强。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. We are interested in imaging and quantifying the constrast generated by susceptibility variations in the mouse brain at high magnetic field. The work is based on the observations by Duyn et al that cytoarchitectural details of the brain can become much more apparent in phase contrast images than with more traditional contrast metrics (e.g. T1,T2, diffusion). We believe this is a fundamentally enabling project that will allow extension into many different areas. The project has several different phases: Phase 1: We will establish the method for phase contrast imaging based upon work done previously at the Lucas Center (Stanford). This will involve measuring and correcting for Bo inhomogenities in the 7T MR system and measuring and correcting for B1 inhomogeneity of the M2M 35 mm quadrature coil. Phase 2: We will image live C57BL/6J mice using a 3D implementation of the phase contrast method at spatial resolution of < 100 microns. We will compare the contrast seen in specific regions of the brain to more traditional imaging protocols (SPGR, FSE, and FIESTA) Phase 3: We will export the method to the 9.4T system to allow imaging of perfusion fixed brains at 21 microns where distribution of the active stain (ProHance) may provide more dramatic phase contrast. Phase 4: We will look toward to possibility of detecting small concentrations of SPIO contrast agent initally in phantoms to determine the potential sensitivity enhancement for molecular imaging.