Hybrid Reconstruction Method for Flow-Sensitive Dephasing Non-Contrast MRA

Andrew J. Wheaton¹, Mitsue Miyazaki²

Flow-sensitive dephasing (FSD) is a subtraction-based non-contrast MRA technique. Conventional FSD acquires two data sets at different flow-dephasing first moments (m1) and phases in the cardiac cycle. The m1 value must be carefully calibrated to avoid losing arterial signal or allowing venous contamination in the subtracted image. This study proposes a hybrid reconstruction method which incorporates a priori knowledge of the relationship between signal intensity and m1 / cardiac cycle in arteries and veins. Using multiple data sets (N=3) as input, the hybrid method improves arterial signal up to 100% while avoiding venous contamination as demonstrated in the lower leg.