Quantification of fluid-tissue exchange using phase alternate labeling with null recovery mri

A system for magnetic resonance imaging of water exchange processes, comprising:

• a primary magnet configured to provide a magnetic field over an imaging volume;
• a magnetic gradient coil configured to generate a spatial encoding in the magnetic field;
• a radiofrequency (RF) coil configured to:
• acquire, from the imaging volume, at a plurality of time points, a plurality of water magnetic resonance signals, said plurality of water magnetic resonance signals comprising a first subset of signals that are labeled for a water exchange process and a second subset of signals that are not labeled;
• and
• a data processor configured to:
• generate, from the first subset of signals, a plurality of labeled images;
• generate, from the second subset of signals, a plurality of control images corresponding to the plurality of labeled images;
• and
• calculate one or more parameters to characterize a water exchange process in the imaging volume between a first water compartment and a second water compartment based on the labeled images and the corresponding control images.