Abstract:
:Dynamic imaging strategies often involve updating certain areas of k-space (i.e., the low spatial frequencies) more frequently than others. However, important dynamic signal changes may occur anywhere in k-space. In this study, a dynamic k-space sampling analysis method was developed to determine the energy error associated with specific dynamic sampling strategies. The method uses the temporal power spectrum of k-space signals to determine the level and k-space locations of sampling errors. The proposed method was used to compare two dynamic sampling strategies (full sequential and keyhole) for a dynamic first-pass bolus simulation and a continuous heart imaging study. The error analysis agreed well with the errors in the reconstructed images. The technique can be used to determine the minimum sampling frequency for any location in the k-space, and may ultimately be used to optimize dynamic sampling strategies. Magn Reson Med 45:550-556, 2001.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Wu Y,Alexander ALdoi
10.1002/mrm.1074subject
Has Abstractpub_date
2001-04-01 00:00:00pages
550-6issue
4eissn
0740-3194issn
1522-2594pii
10.1002/mrm.1074journal_volume
45pub_type
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