MR imaging and spectroscopy using hyperpolarized 129Xe gas: preliminary human results

Area of Science:

• Medical Imaging
• Nuclear Magnetic Resonance (NMR) Spectroscopy
• Quantum Optics

Background:

• Hyperpolarized 129Xe gas offers unique imaging capabilities for biological tissues.
• Previous methods limited the quantity and polarization of 129Xe gas available for research.
• Advanced imaging of lung gas-spaces and dissolved-phase tissues remains a challenge.

Purpose of the Study:

• To demonstrate a novel method for generating liter quantities of hyperpolarized 129Xe gas.
• To obtain the first human chest imaging and chest/head spectroscopy results using this new method.
• To assess the potential for high-resolution medical imaging of the lungs and brain.

Main Methods:

• Developed a new xenon laser-polarization technique for large-scale hyperpolarized 129Xe gas production.
• Acquired cross-sectional images of lung gas-spaces with a voxel volume of 0.9 cm3.
• Obtained 129Xe spectroscopy data from the human chest and head, detecting dissolved-phase resonances.

Main Results:

• Achieved polarization levels of approximately 2% for 129Xe gas.
• Generated the first 129Xe imaging results from the human chest (SNR 28).
• Detected three dissolved-phase resonances in chest spectra and one in head spectra, likely from brain parenchyma.

Conclusions:

• The new xenon laser-polarization method enables significant advancements in hyperpolarized 129Xe applications.
• Results suggest potential for high-resolution gas-phase lung imaging comparable to conventional proton imaging.
• Feasibility of dissolved-phase imaging of chest and brain with high resolution is demonstrated.