Improvements to Control Scan of ASL-perfusion MRI by Improving Null Pulse for Use with the Repeated Shallow Flip Angle Excitations
Jahng G, Weiner M, Schuff N, Matson G
University of California, San Francisco
The goal of this work is to improve the sensitivity of arterial spin labeling (ASL) perfusion MRI by reducing excitation of inflowing spins during the control pulse. We propose an improved control scheme for pseudo-continuous ASL based on the repeated shallow flip angle excitations using a null pulse. Computer simulations demonstrate immunity of the proposed null pulse over flow velocity of 20-60 cm/sec and off-resonance conditions up to +/- 40 Hz. In conclusion, the new null pulse should improve the control scan of continuous ASL based on repeated shallow flip angle excitations, thus improving sensitivity of ASL perfusion.