Abstract:
PURPOSE:Breath-holding is an established strategy for reducing motion artifacts in abdominal imaging. However, the breath-holding capabilities of patients are often overstrained by scans with large coverage and high resolution. In this work, a new strategy for coping with resulting incomplete breath-holds in abdominal imaging is suggested. METHODS:A sampling pattern is designed to support image reconstruction from undersampled data acquired up to any point in time using compressed sensing and parallel imaging. In combination with a navigator-based detection of the onset of respiration, it allows scan termination and thus reconstruction only from consistent data, which suppresses motion artifacts. The spatial resolution is restricted by a lower bound of the sampling density and is increased over the scan, to strike a compromise with the signal-to-noise ratio and undersampling artifacts for any breath-hold duration. RESULTS:The sampling pattern is optimized in phantom experiments and is successfully applied in abdominal gradient-echo imaging including water-fat separation on volunteers. CONCLUSIONS:The new strategy provides images in which motion artifacts are minimized independent of the breath-holding capabilities of patients, and which enhance in terms of spatial resolution, signal-to-noise ratio, and undersampling artifacts with the a priori unknown breath-hold duration actually achieved in a particular scan.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Gdaniec N,Eggers H,Börnert P,Doneva M,Mertins Adoi
10.1002/mrm.24829subject
Has Abstractpub_date
2014-05-01 00:00:00pages
1733-42issue
5eissn
0740-3194issn
1522-2594journal_volume
71pub_type
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