Low-field He-3 nuclear magnetic resonance in human lungs
Résumé
We report the first in vivo NMR experiments performed with hyperpolarised He-3 gas at 0.1 T. Hyperpolarisation is achieved by laser optical pumping of He-3 atoms in the metastable triplet state. Longitudinal relaxation times of nuclear magnetisation of the order of 35 s are measured in human lungs. Very long transverse relaxation times of a few seconds are also observed. This work establishes the possibility of magnetic resonance imaging of human lung airways at low field.