Non-contrast-enhanced Flow-independent Peripheral Angiography using a 3D Concentric Cylinders Trajectory

Introduction: Non-contrast-enhanced flow-independent angiography (FIA) exploits intrinsic tissue parameters such as T1, T2 and chemical shift to generate vessel contrast [1]. Unlike flow-dependent methods, FIA can generate stable vessel contrast even with slow flow potentially in the diseased leg. Magnetization-prepared 3D SSFP sequences have been of interest for FIA [2,3], but an important issue with these sequences is artery-vein contrast. Recently, an efficient and robust 3D SSFP imaging sequence using a concentric cylinders k-space trajectory was developed [4]. Concentric cylinders offer the following advantages: a) fewer excitations required than a comparable 3DFT sequence; b) robustness to off-resonance effects; and c) inherent centric view-ordering, crucial for magnetizationprepared imaging [4-6]. In this work, the 3D concentric cylinders trajectory was incorporated into a T2-prepared SSFP FIA sequence for scan-time reduction that can be traded off to improve the arteryvein contrast in the lower extremities.