Velocity selective radiofrequency pulse trains

The incorporation of velocity-encoding gradient pulses in RF-pulse trains i s proposed and examined, Velocity selective perturbation is shown to be ana logous in many respects to the well established use of trains of short RF-p ulses for chemical shift selective perturbation. Velocity selective perturb ation is viable in a biomedical setting only if additional RF refocusing pu lses are inserted between the individual RF-pulse elements, Aspects of velo city selective excitation saturation and inversion are examined, and new in version pulse trains proposed. The selective perturbation of both flowing a nd stationary spins is demonstrated in phantoms and possible biomedical app lications of these pulse trains are discussed. (C) 1999 Academic Press.