Abstract: A velocity selective preparation method, for Velocity Selective Magnetisation Transfer Insensitive labelling technique (VS-TILT), said VS-TILT method using non-selective RadioFrequency (RF) pulses and magnetic field gradients to modulate the longitudinal magnetization of moving spins in magnetic resonance imaging that is insensitive to diffusion effects, said method comprising the steps of: a) play out two velocity selective pulses: VS-A and VS-B, sequentially without any spoiling between said pulses; b) each individual pulse VS-A and VS-B having half the first gradient moment m1 of the original velocity selective pulse; c) assigning the VS-TILT tag condition gradients to have the same polarity, such that total m1 is perserved; and d) assigning the VS_TILT control condition, negating the n gradients in the first pulse such total m1=0, but the b-value remains unchanged.

Abstract: A velocity selective preparation method is disclosed, for velocity selective arterial spin labelling (VSASL), the VSASL method using non-selective radiofrequency pulses and magnetic field gradients to modulate the longitudinal magnetization of the spins as a function of their velocity, wherein said velocity selective preparation method comprises an n-segment B1 insensitive rotation that is resistant to eddy current artifacts.