A 3D Fast Multiphase DENSE MRE Sequence with Stack-of-Star Radial Sampling, Interleaved Multi-Slab Acquisition and Hadamard Encoding

Conventional gradient echo (GRE) based Magnetic Resonance Elastography (MRE) suffers from long TE and scan time at low mechanical excitation (<25Hz). Displacement Encoding with a Stimulated Echo (DENSE) can record displacement with short TR, useful for low-frequency excitation. Here, 3D excitation was used to compensate for potential signal loss. A multiphase acquisition scheme with stack-of-star radial sampling was also used along with interleaved multi-slab acquisition and Hadamard encoding for MRE acceleration. Phantom experiments were conducted for validation. 32 slices brain MRE scan at 20Hz can be achieved in 11min30s, 5 folds faster than conventional GRE-based MRE.