QUANTITATE 23NA EQUILIBRIUM MAGNETIZATION USING MULTIPLE QUANTUM FILTERED NMR

骨关节炎（OA）是一种软骨退行性疾病， 导致组织丧失正常功能 OA早期退行性变 软骨与蛋白聚糖（PG）的损失有关。 我们有 最近表明，可以测量软骨中的PG损失， 通过关节23 Na MRI定量钠间接 体内和体外的软骨。 我们想进一步描述 钠，根据其环境将其分为两种。 在生物组织中存在游离钠和结合钠。 游离钠通常是各向同性运动，而结合钠 经历各向异性运动，因此23Na NMR信号衰减是 呈双指数分布 我们正试图精确地 用23 Na定量测定骨模和软骨中结合的钠的量 多量子滤波（MQF）NMR。 通过测量平衡 SQ和MQF信号的磁化将使人们能够定量 钠的键分数。 我们已经在幻影中测量了这一点， 目前正在软骨中进行测量。

Osteoarthritis (OA) is a cartilage degenerative disease that leads to loss of proper function of the tissue. Early degeneration of OA cartilage is associated with the loss of proteoglycans (PG). We have recently shown that it is possible to measure PG loss in cartilage indirectly by quantitation of sodium by 23Na MRI of articular cartilage in-vivo and in-vitro. We want to further characterize this sodium by classifying it into two species based on their environments. In biological tissues there exists free and bound sodium fractions. The free sodium is usually in isotropic motion whereas bound sodium undergoes anisotropic motion and hence the 23Na NMR signal decay is biexponential in these tissues. We are attempting to precisely quantify the amount of bound sodium in phantoms and cartilage by 23Na Multiple Quantum Filtered (MQF) NMR. By measuring the equilibrium magnetization by both SQ and MQF signals will enable one to quantitate bond fraction of sodium. We ha ve measured this in phantoms and currently in the process of measuring in cartilage.