Method and apparatus of background suppression in MR imaging using spin locking

A method of MR flow imaging comprising the steps of:

• selecting an ROI in which flow therein will be imaged;
• applying a train of low energy RF pulses to suppress magnetization of spins in the ROI;
• exciting longitudinal magnetization of inflowing spins in the ROI;
• and
• acquiring MR data from the inflowing spins.

A pulse sequence to suppress background tissue, the pulse sequence comprising:

• a slice selective pulse to spatially select an ROI for spin suppression;
• a number of non-selective RF pulses played out after the slice selective pulse to suppress magnetization of static spins within the ROI;
• and
• an imaging pulse played out after the number of non-selective RF pulses to excite inflowing spins to the ROI.

A computer readable storage medium having a computer program stored thereon and representing a set of instructions that when executed by a computer causes the computer to:

• apply a slice selective RF pulse and gradient to spatially define a volume for background suppression;
• apply a train of non-selective RF pulses to lock spins in the volume;
• and
• apply another slice selective RF pulse to excite longitudinal magnetization of inflowing spins to the volume.