3He spin exchange cells for magnetic resonance imaging
3He spin exchange cells for magnetic resonance imaging
复制标题
用于磁共振成像的 3He 自旋交换细胞
DOI：
10.1063/1.1487438
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发表时间：
2002
影响因子：
3.2
通讯作者：
B. Saam
中科院分区：
文献类型：
--
作者：
R. Jacob;S. Morgan;B. Saam
我们提出了一种一致制造玻璃小室的方案，以提供用于肺磁共振成像的超极化(HP)3He。产生HP3He的方法是自旋交换光泵浦。阀门单元必须在高达15个大气压的压力下容纳1大气压的气体⋅L。由于特征自旋交换时间为几个小时，3He的纵向核弛豫时间t1必须为几十个小时，并且对重复填充和复极化具有很强的耐受性。与细胞壁的碰撞是松弛的一个重要且往往占主导地位的原因。从历史上看，通过细胞制造过程对壁弛豫进行持续控制一直是困难的。随着玻璃中磁性表面位的一种重要的壁弛豫机制的发现，以及对Rb金属对长壁弛豫时间重要性的进一步证实，我们成功地发展了一种从廉价的和低成本的玻璃中制备3He自旋交换池的方案。
We present a protocol for the consistent fabrication of glass cells to provide hyperpolarized (HP) 3He for pulmonary magnetic resonance imaging. The method for producing HP 3He is spin-exchange optical pumping. The valved cells must hold of order 1 atm⋅L of gas at up to 15 atm pressure. Because characteristic spin-exchange times are several hours, the longitudinal nuclear relaxation time T1 for 3He must be several tens of hours and robust with respect to repeated refilling and repolarization. Collisions with the cell wall are a significant and often dominant cause of relaxation. Consistent control of wall relaxation through cell fabrication procedures has historically proven difficult. With the help of the discovery of an important mechanism for wall relaxation that involves magnetic surface sites in the glass, and with the further confirmation of the importance of Rb metal to long wall-relaxation times, we have developed a successful protocol for fabrication of 3He spin exchange cells from inexpensive an...