Diffusion-weighted magnetic resonance imaging (MRI) without susceptibility artifacts: single-shot stimulated echo acquisition mode (STEAM) MRI with iterative reconstruction and spatial regularization

This work describes a new method for diffusion-weighted (DW) magnetic resonance imaging (MRI) without susceptibility artifacts. The technique combines DW spin-echo module and single-shot stimulated echo acquisition mode (STEAM) MRI readout with undersampled radial trajectories covers volume by gapless series of cross-sectional slices. In first step, optimal coil sensitivities all slices are obtained from non-DW acquisitions nonlinear inverse reconstruction regularization to the image directly neighboring slice. second these used compute images linear spatial image. Proof-of-principle applications brain (51 sections) prostate (31 healthy subjects were realized protocol two b-values 6 gradient directions at 3 T. Including averaging measuring times studies 1.0×1.0×3.0 mm3 resolution (b =1,000 s mm-2) 1.4×1.4×3.0 =600 2.5 min 4.5 min, respectively. All reconstructions accomplished online use multi-GPU computer integrated into system. resulting images, mean averaged across maps apparent diffusion coefficient confirm absence geometric distortions or false signal alterations demonstrate diagnostic quality. novel STEAM artifacts warrants extended clinical trials.