Regensburg 2010 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

ST: Fachverband Strahlen- und Medizinphysik

ST 8: Magnetism and Medicine (MA and ST)

ST 8.4: Invited Talk

Wednesday, March 24, 2010, 11:00–11:30, H1

Biomedical Magnetic Resonance using Hyperpolarized Gases and Liquids — •Laura Schreiber — Section of Medical Physics, University Medical Center, Mainz, Germany

Biomedical magnetic resonance imaging (MRI) is an inherently insensitive methodology since it requires mmoL amounts of the detected nuclei. Therefore, MRI of respiratory gases (O2, CO2, N2) is not feasible in-vivo. Sophisticated hyperpolarization techniques, i.e. optical pumping of nuclear states, increase the nuclear polarization of the noble gases 3He and 129Xe by five orders of magnitude and thus permit a direct imaging of the inhaled gases as they distribute within the lung of a human subject. Therefore, assessment of human lung ventilation becomes feasible. Moreover, techniques have been developed to measure functional lung parameters like intrapulmonary oxygen concentration or the integrity of the alveoli using hyperpolarized gases.

Hyperpolarization of liquids has also become feasible recently using Dynamic Nuclear Polarization (DNP) or Parahydrogen Induced Polarization (PHIP) techniques. This is of particular interest for low sensitivity nuclei like 13C where measurement times are long. Now metabolic studies with DNP- or PHIP-hyperpolarized 13C-labeled substances have become feasible with measurement times on the order of seconds, thus permitting non-invasive assessment of reaction kinetics in-vivo.