Feasibility of functional magnetic resonance lung imaging in Australia with long distance transport of hyperpolarized helium from Germany

Abstract

MRI of the lung using hyperpolarized helium as an inhaled contrast agent has important research applications and clinical potential. Owing to the limited availability of hyperpolarized helium, this type of imaging has not been performed in the human lung outside of North America or Europe. The objective of this study was to test the feasibility of imaging human lungs in Australia using hyperpolarized helium gas imported from Germany. A Bruker 2-Tesla whole-body magnetic resonance scanner located in Brisbane, Australia was adapted with a helium-3 radiofrequency transceiver coil. Helium-3 was hyperpolarized to 72% in Mainz, Germany and airfreighted to Brisbane. The time taken for the journey was 32 h and scanning was performed 36-40 h after departure from Mainz, with an estimated polarization level of 44%. Procedures were developed to transfer 300 mL of the hyperpolarized helium to Tedlar bags filled with 700 mL of nitrogen. Healthy volunteers inhaled the 1 L helium/nitrogen mixture from FRC, and imaging was performed with a 10 s breathhold. Imaging showed very detailed and even ventilation of all regions of the lung with a good signal-to-noise ratio. No adverse effects of inhaling the gas mixture were noted. This report of MRI of the human lung using hyperpolarized helium demonstrates the feasibility of long distance gas transport from Germany to Australia. This will help to facilitate research and clinical application of this innovative functional lung imaging technique.