Polarized Xenon Production: Compact Magnetic Field

描述（由申请人提供）：

DESCRIPTION (provided by applicant): Since its first demonstration as an imaging agent in MRI nearly a decade ago, the promise of hyperpolarized xenon has captured the attention of the research community. It can be introduced into a subject non-invasively by breathing, and has a well-understood short-term biological effect. Relative to hyperpolarized helium, its advantages include its natural abundance and low cost. Both hyperpolarized xenon and helium have demonstrated utility in lung imaging, and quantifying lung disease. In contrast to helium, however, hyperpolarized xenon has a high solubility in fluids and tissues and a characteristic chemical shift, revealing its microscopic environment in dissolved-phase imaging. Consequently, the time dependence of its transport and absorption offer prospects for functional imaging of perfusion. Using NIH R21 and R15 funds, the UNH group demonstrated a new type of xenon polarizer that flows the gas mixture at relatively high velocity and low pressure along a direction opposite to the laser beam. This polarizer demonstrated polarization of almost 50% for a production rate of one liter per hour. The figure-of-merit (polarization times production rate) of this polarizer presently exceeds all other polarizer technologies by an order of magnitude. We request STTR funding to develop a novel magnetic subsystem incorporating coil windings, permanent magnets, and shielding iron to reduce the size (footprint) of this polarizer by a factor of three, and substantially reduce its sitting requirements. This development helps to convert this laboratory installation to a practical hospital-based device. Hyperpolarized gas has already demonstrated utility in diagnosing and quantifying lung disease. We present technological, physiological, and economic arguments that hyperpolarized xenon can and perhaps will surpass gadolinium as the contrast agent of choice in a broad spectrum of diagnostic imaging protocols.