Chawla M S, Chen X J, Möller H E, Cofer G P, Wheeler C T, Hedlund L W, Johnson G A
Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC 27710, USA.
Proc Natl Acad Sci U S A. 1998 Sep 1;95(18):10832-5. doi: 10.1073/pnas.95.18.10832.
Laser-polarized gases (3He and 129Xe) are currently being used in magnetic resonance imaging as strong signal sources that can be safely introduced into the lung. Recently, researchers have been investigating other tissues using 129Xe. These studies use xenon dissolved in a carrier such as lipid vesicles or blood. Since helium is much less soluble than xenon in these materials, 3He has been used exclusively for imaging air spaces. However, considering that the signal of 3He is more than 10 times greater than that of 129Xe for presently attainable polarization levels, this work has focused on generating a method to introduce 3He into the vascular system. We addressed the low solubility issue by producing suspensions of 3He microbubbles. Here, we provide the first vascular images obtained with laser-polarized 3He. The potential increase in signal and absence of background should allow this technique to produce high-resolution angiographic images. In addition, quantitative measurements of blood flow velocity and tissue perfusion will be feasible.
激光极化气体（³He和¹²⁹Xe）目前在磁共振成像中用作强信号源，可安全地引入肺部。最近，研究人员一直在使用¹²⁹Xe研究其他组织。这些研究使用溶解在脂质囊泡或血液等载体中的氙。由于氦在这些材料中的溶解度远低于氙，³He一直仅用于气腔成像。然而，考虑到对于目前可达到的极化水平，³He的信号比¹²⁹Xe的信号大10倍以上，这项工作专注于开发一种将³He引入血管系统的方法。我们通过制备³He微泡悬浮液解决了低溶解度问题。在此，我们提供了用激光极化³He获得的首批血管图像。信号的潜在增加和无背景应该使该技术能够产生高分辨率血管造影图像。此外，血流速度和组织灌注的定量测量将是可行的。
