Magnetic resonance imaging using polarized noble gases
Résumé
A new technique of medical imaging based on NMR has been developed, making use of spin polarized gases, He-3 or Xe-129, introduced inside the human body, where the polarization lives long enough to allow images to be taken. 3D images have been recorded for the lungs of living animals and humans with a resolution of a few mm(3). The polarization methods are based on optical pumping, for which we discuss the possible improvements in the technology of the required cw infrared lasers. We also display the advantages opened up by MRT in low magnetic field. Finally we comment on the perspectives of this MRI method in the field of medicine and biophysics, especially in functional ventilation and perfusion imaging.