SPIN-LOCK SODIUM MRI OF THE HUMAN BRAIN

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。所列机构为 中心，不一定是研究者的机构。 质子T1 <$MRI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，这是由于其探测慢分子运动的能力。 尽管已经研究了钠的自旋锁定光谱作为选择性地测量 探测慢分子运动和各向异性环境中涉及的钠核， 目前尚无文献报告自旋锁钠MRI数据。 很大一部分 生物组织中的钠离子通过静电结合与大分子络合 位点及其与结合水部分的相互作用。 几种组织病理学，例如中风 和骨关节炎，涉及复合部分的运动特征的实质性变化， 钠离子自旋 T2或T2* 的测量仅对通过光谱的慢运动敏感。 密度在零频率;缓慢的动态探测更有效地通过应用一个 亚千赫范围的强射频场 我们假设自旋锁钠磁共振成像会产生 基于生物组织中的大分子含量的显著对比度，这是由于其对慢 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.