9.4Tesla/310mm MR Imaging and Spectroscopy System

描述（由申请人提供）： 基础核磁共振中心的科学家们。研究，埃文斯顿，伊利诺伊州请求部分资金支持购买9.4T/305毫米口径水平轴MR扫描仪成像兔子，大鼠和小鼠。成像仪将有主动屏蔽超导磁体，并将配备两个集成梯度匀场线圈，双通道射频发射器和双接收器系统。该中心主要隶属于埃文斯顿西北医疗保健和西北大学作为罗伯特H。卢里癌症中心。要求安装高视场成像仪的理由是，受资助项目需要更高的空间分辨率、时间分辨率、信噪比和对比度，而目前使用的4.7 T成像仪无法满足这些要求。对这一请求的支持以在4.7 T和一台已停止工作的垂直轴Omega 400 WB分光计上获得的数据的形式广泛提出。将使用所提出的成像仪的项目根据所采用的MR方法分为三个部分进行描述：（i）功能成像，（ii）扩散张量成像，（iii）对比度增强的新方法。使用清醒兔子模型的功能性神经成像项目包括学习、记忆、衰老、麻醉以及BOLD fMRI与潜在神经元活动之间的关系的研究。9.4T成像仪将通过二次增加小微静脉和毛细血管的BOLD对比度而使这些项目受益，而大血管的贡献最小。在9.4T下预期的SNR的两倍增加将允许以更大的空间特异性研究神经元回路中的结构。在0.2mm 3或更小的量级上的高空间分辨率对于研究诸如皮质柱和皮质层或具有特异性的感觉-边缘-小脑系统中的那些结构中的激活是必不可少的。通过扩散张量成像测量各向异性被五个项目用于促进对神经系统疾病（如AD、ALS、MS和缺氧缺血）中细胞环境变化的理解。大脑和脊髓的各向异性测量将大大受益于9.4T下可用的SNR增加，因为这些测量的准确性受到SNR差的严重影响。在这些研究中，高空间分辨率的要求，重点是在小鼠脊髓或小鼠海马CA 1，CA 3和DG区的灰质和白色物质隔间内的亚结构，只能满足增加灵敏度的9.4 T成像仪。造影剂领域的研究重点是开发靶向特异性试剂以研究细胞迁移和信号传导，以及克服顺磁试剂在高磁场下的局限性。报告指出，在购买成像仪方面，机构将大力支持分摊费用。负责该仪器的科学工作人员具有小动物成像方面的专业知识和经验。

DESCRIPTION (provided by applicant): Scientists at the Center for Basic M.R. Research, Evanston, Illinois request partial funding support to purchase a 9.4T/305mm bore horizontal axis MR scanner to image rabbits, rats and mice. The imager will have actively shielded superconducting magnet and will be fitted with two integrated gradient -shim coils, dual channel RF transmitter and dual receiver system. The center has primary affiliation to Evanston Northwestern Healthcare and secondary affiliation to Northwestern University as a core facility of the Robert H. Lurie Cancer Center. Justification of the requested high field imager is based on the demand for higher spatial resolution, temporal resolution, signal to noise ratio and contrast to noise ratio in funded projects that cannot be met by the 4.7T imager currently in use. Support for the request is presented extensively in the form of data obtained at 4.7T and on a vertical axis Omega 400WB spectrometer that is no longer operational. Projects that will use the proposed imager are described under three sections based on the MR methodology employed: (i) functional imaging, (ii) diffusion tensor imaging, and (iii) novel approaches to contrast enhancement. Functional neuroimaging projects that use a conscious rabbit model include studies of learning, memory, aging, anesthesia and the relationship between BOLD fMRI and underlying neuronal activity. The 9.4T imager will benefit these projects by increasing BOLD contrast quadratically for small venuoles and capillaries with minimal contribution from the large vessels. The two-fold increase in SNR expected at 9.4T will allow structures in neuronal circuitry to be studied with greater spatial specificity. High spatial resolution on the order of 0.2mm3 or less is essential to study activation in structures such as cortical columns and cortical layers or those in the sensory-limbic-cerebellar system with specificity. Measurement of anisotropy by diffusion tensor imaging is employed by five projects to advance understanding of changes to the cellular environment in neurological disorders such as AD, ALS, MS, and hypoxia-ischemia. Anisotropy measurements in brain and spinal cord will greatly benefit from the increased SNR available at 9.4T since accuracy in these measurements is severely affected by poor SNR. High spatial resolution requirements in these studies which focus on substructures within gray and white matter compartments of the mouse spinal cord or CA1, CA3 and DG regions in mouse hippocampus can only be met by the increased sensitivity of the 9.4T imager. Research in the area of contrast agents focuses on developing target-specific agents to study cell migration and signaling and on overcoming limitations of paramagnetic agents at high magnetic fields. Strong institutional support for cost-sharing in the purchase of the imager is indicated. Scientific staff responsible for the instrument has expertise and experience in small animal imaging.