Near-Contiguous Spin Echo Imaging Using Matched-Phase RF and Its Application in Velocity-Selective Arterial Spin Labeling

Zungho Zun¹, Brian A. Hargreaves¹, Greg Zaharchuk¹

A matched-phase 90-180 pair can achieve sharper slice profile, lower peak B1, or shorter echo time than conventional 90 and 180 RF pulses in spin echo imaging. We demonstrate that a matched-phase pair can be used to reduce the perturbation to the adjacent slice, enabling smaller slice spacing in multislice perfusion imaging using velocity-selective arterial spin labeling (ASL). The matched-phase pairs allowed the slice spacing to be reduced to one third of the imaging slice thickness, without compromising SNR or ASL signal stability.