BIOLOGICAL MAGNETIC-RESONANCE-IMAGING USING LASER POLARIZED XE-129
BIOLOGICAL MAGNETIC-RESONANCE-IMAGING USING LASER POLARIZED XE-129
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DOI：
10.1038/370199a0
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发表时间：
1994-07-21
期刊：
影响因子：
64.8
通讯作者：
WISHNIA, A
中科院分区：
文献类型：
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作者：
ALBERT, MS;CATES, GD;WISHNIA, A
根据目前的实施，磁共振成像(MRI)依靠组织中水分子的质子来提供核磁共振信号。然而，众所周知，质子很难在一些感兴趣的生物环境中成像，特别是肺(1)和类脂双层膜，如大脑中的那些(2)。在这里，我们表明，当激光光泵和自旋交换(3-6)增加原子的核自旋极化时，Xe-129气体可以用于高分辨率磁共振成像。这个过程产生了超极化的Xe-129，其中的磁化强度增加了大约10(5)倍。通过将超极化Xe-129引入小鼠肺部，我们获得了比质子磁共振(1，7)或发射断层扫描(8，9)更快和更高分辨率的肺气体空间图像。由于氙气(一种安全的全身麻醉剂)迅速、安全地从肺转移到血液，然后转移到其他组织(8，9)，在那里它集中在脂质(10-15)和蛋白质(13，15-18)成分中，因此也可以获得循环系统、大脑和其他重要器官的图像。由于Xe-129的磁性行为对其环境非常敏感，并且不同于(H2O)-H-1，因此使用超极化Xe-129的磁共振成像应该涉及到明显和敏感的组织对比机制。
AS currently implemented, magnetic resonance imaging (MRI) relies on the protons of water molecules in tissue to provide the NMR signal. Protons are, however, notoriously difficult to image in some biological environments of interest, notably the lungs(1) and lipid bilayer membranes such as those in the brain(2). Here we show that Xe-129 gas can be used for high-resolution MRI when the nuclear-spin polarization of the atoms is increased by laser optical pumping and spin exchange(3-6). This process produces hyperpolarized Xe-129, in which the magnetization is enhanced by a factor of about 10(5). By introducing hyperpolarized Xe-129 into mouse lungs we have obtained images of the lung gas space with a speed and a resolution better than those available from proton MRI(1,7) or emission tomography(8,9). As xenon (a safe general anaesthetic) is rapidly-and safely transferred from the lungs to blood and thence to other tissues(8,9), where it is concentrated in lipid(10-15) and protein(13,15-18) components, images of the circulatory system, the brain and other vital organs can also be obtained. Because the magnetic behaviour of Xe-129 is very sensitive to its environment, and is different from that of (H2O)-H-1, MRI using hyperpolarized Xe-129 should involve distinct and sensitive mechanisms for tissue contrast.