Abstract:
:Flow-independent angiography is a non-contrast-enhanced technique that can generate vessel contrast even with reduced blood flow in the lower extremities. A method is presented for producing these angiograms with magnetization-prepared balanced steady-state free precession (bSSFP). Because bSSFP yields bright fat signal, robust fat suppression is essential for detailed depiction of the vasculature. Therefore, several strategies have been investigated to improve the reliability of fat suppression within short scan times. Phase-sensitive SSFP can efficiently suppress fat; however, partial volume effects due to fat and water occupying the same voxel can lead to the loss of blood signal. In contrast, alternating repetition time (ATR) SSFP minimizes this loss; however, the level of suppression is compromised by field inhomogeneity. Finally, a new double-acquisition ATR-SSFP technique reduces this sensitivity to off-resonance. In vivo results indicate that the two ATR-based techniques provide more reliable contrast when partial volume effects are significant.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Cukur T,Lee JH,Bangerter NK,Hargreaves BA,Nishimura DGdoi
10.1002/mrm.21921subject
Has Abstractpub_date
2009-06-01 00:00:00pages
1533-9issue
6eissn
0740-3194issn
1522-2594journal_volume
61pub_type
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