Multi-band PROPELLER imaging with auto-calibration

Abstract

PROPELLER MRI is widely used nowadays for motion correction. One major drawback of PROPELLER MRI is the long scan time. Previous studies have investigated in-plane acceleration (SENSE and GRAPPA) in PROPELLER1,5. However, multi-band (MB) simultaneous multi-slice acquisition, without SNR penalty proportional to square root of acceleration ratio, can be a more suitable solution for accelerating PROPELLER. In addition, MB acquisition combining PINS RF pulses2 can reduce RF pulse power deposition, which is particularly useful for alleviating the SAR issue in FSE-PROPELLER at high field. A considerably low g-factor is possible in MB PROPELLER because its rotating phase encoding directions can consequently lead to a well-conditioned unwrapping problem. Another advantage of MB PROPELLER is that 3D coil sensitivity maps (CSMs) can be directly estimated from the oversampled k-space center, without acquiring additional calibration data.