Abstract:
:Rapid MR imaging using the stimulated echo acquisition mode (STEAM) technique yields single-shot images without any sensitivity to resonance offset effects. However, the absence of susceptibility-induced signal voids or geometric distortions is at the expense of a somewhat lower signal-to-noise ratio than EPI. As a consequence, the achievable spatial resolution is limited when using conventional Fourier encoding. To overcome the problem, this study combined single-shot STEAM MRI with radial encoding. This approach exploits the efficient undersampling properties of radial trajectories with use of a previously developed iterative image reconstruction method that compensates for the incomplete data by incorporating a priori knowledge. Experimental results for a phantom and human brain in vivo demonstrate that radial single-shot STEAM MRI may exceed the resolution obtainable by a comparable Cartesian acquisition by a factor of four.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Block KT,Frahm Jdoi
10.1002/mrm.21401subject
Has Abstractpub_date
2008-04-01 00:00:00pages
686-91issue
4eissn
0740-3194issn
1522-2594journal_volume
59pub_type
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