SPIN-LOCK SODIUM MRI OF THE HUMAN BRAIN

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 核磁共振研究表明，自旋锁定可以提供独特的和临床上有用的 对比度与大分子含量相关，因为它能够探测慢分子运动。 尽管钠的自旋锁定光谱已经被作为一种选择性地 探测慢分子运动和各向异性环境中涉及的钠核，以 目前尚无文献报道自旋锁钠核磁共振数据。一大部分 生物组织中的钠离子通过静电结合与大分子络合 以及它们与结合水分数的相互作用。几种组织病理学，例如中风 和骨关节炎，涉及复杂部分的运动特征的实质性变化 钠自旋。T2或T2*的测量仅通过光谱对慢动作敏感 密度在零频率；通过应用 亚千赫兹范围内的强射频场。我们假设自旋锁定钠核磁共振将产生 基于生物组织中大分子含量的显著对比，这是由于其对慢速的敏感性 分子运动。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Proton T1¿ MRI studies have shown that spin-locking can provide unique and clinically-useful contrast correlated to macromolecular content due to its ability to probe slow molecular motion. Although spin-locking spectroscopy of sodium has been investigated as a means to selectively detect sodium nuclei involved in slow molecular motion and anisotropic environments, to knowledge there is currently no literature reporting spin-lock sodium MRI data. A large fraction of sodium ions in biological tissue are complexed to macromolecules through electrostatic binding sites and their interactions with the bound water fraction. Several tissue pathologies, e.g. stroke and osteoarthritis, involve substantial changes to motional characteristics of the complexed fraction of sodium spins. Measurements of T2 or T2* are sensitive to slow motion only through the spectral density at zero frequency; slow dynamics are probed more efficiently through the application of a strong RF fields in the sub-kilohertz range. We hypothesize that spin-lock sodium MRI will generate significant contrast based on macromolecular content in biological tissue due to its sensitivity to slow molecular motion.