Diffusion-weighted single-shot line scan imaging of the human brain

Single-shot line scan imaging (LSI) was adapted to diffusion-weighted (DW) MRI by replacing the initial 90° radiofrequency pulse of the underlying high-speed stimulated echo sequence by a DW spin-echo preparation period. Implementation on a 2.0 T whole-body MRI system yielded DW images of the human brain with b factors of 750 s mm^-2 and total imaging times of about 500 ms either for a single slice at 1.5 × 3.0 × 6 mm³ resolution or simultaneously for up to seven slices at 3.75 × 3.75 × 8 mm³ resolution. Isotropic DW images and maps of the trace of the diffusion tensor were calculated from four scans with different combinations of three orthogonal diffusion gradients. DW LSI combines high speed with robustness against image artifacts caused by motion (no phase ghosting) and tissue susceptibility differences (no signal losses, no geometric distortions). Because the latter is an important advantage over echo-planar imaging, DW LSI may find useful applications despite a limited signal-to-noise ratio. Magn Reson Med 42:772–778, 1999. © 1999 Wiley-Liss, Inc.