Abstract:
: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.
journal_name
Proc Natl Acad Sci U S Aauthors
Chawla MS,Chen XJ,Möller HE,Cofer GP,Wheeler CT,Hedlund LW,Johnson GAdoi
10.1073/pnas.95.18.10832subject
Has Abstractpub_date
1998-09-01 00:00:00pages
10832-5issue
18eissn
0027-8424issn
1091-6490journal_volume
95pub_type
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