NMR Velocity-Selective Excitation Composites for Flow and Motion Imaging and Suppression of Static Tissue Signal

We propose a technique aimed at increasing the sensitivity of magnetic resonance imaging (MRI) measurements to the signal from moving material. The technique is formulated within the framework of a velocity phase-encoding strategy. The salient new feature of the protocol is the application of an excitation pulse, following the conventional 90°excitation and bipolar phase gradient modulation pulses, which rotates the magnetization through -90°. The whole comprises a velocity-selective excitation composite which leaves only magnetization of moving material in the transverse plane.