Temporally constrained respiratory gating improves continuously moving table MRI during free breathing. Issue 1 (12th December 2012)

• Record Type: Journal Article
• Authors: Baumann, Tobias; Kannengiesser, Stefan A.R.; Honal, Matthias
• Is Part Of: Journal of magnetic resonance imaging. Volume 38:Issue 1(2013)
• Page Start: 198
• Page End: 205
• Publication Date: 2012-12-12
• Subjects: Magnetic resonance imaging -- Periodicals; 616
• DOI: 10.1002/jmri.23964
• Languages: English
• ISSNs: 1053-1807

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="jmri23964-sec-0001" sec-type="section"> <title>Purpose</title> <p>To evaluate a novel breathing motion correction algorithm for continuously moving table magnetic resonance imaging (CMT‐MRI) that optimizes motion consistency in a fixed time span.</p> </sec> <sec id="jmri23964-sec-0002" sec-type="section"> <title>Materials and Methods</title> <p>In 22 patients CMT‐MRI was performed during free breathing. During a preparatory phase (constant) or continuously during the scan (adaptive) gating thresholds were computed from breathing states that should allow for motion consistent <italic>k</italic>‐space sampling. After data from a first <italic>k</italic>‐space traversal was acquired irrespective of breathing motion, subsequently <italic>k</italic>‐space lines with discordant breathing states were reacquired below the gating threshold. Time constraints of CMT‐MRI were respected, because a fixed time was allocated for reacquisition. Image quality and lesion depiction were evaluated on images reconstructed from the first traversal and motion‐corrected images.</p> </sec> <sec id="jmri23964-sec-0003" sec-type="section"> <title>Results</title> <p>Compared to constant thresholds, gating with adaptive thresholds led to a higher number of reacquired <italic>k</italic>‐space lines (60.1%/41.7%) and a larger fraction of motion consistent final <italic>k</italic>‐space lines (96.6%/78.8%). Adaptive gating induced a significant increase in image quality for all regions affected by breathing motion. Only one of 22 lesions was not depicted on the adaptively corrected images, whereas 15 were readily appreciable.</p> </sec> <sec id="jmri23964-sec-0004" sec-type="section"> <title>Conclusion</title> <p>Temporally constrained respiratory gating with adaptive thresholds allows for fully sampled, motion‐corrected CMT‐MRI acquisitions during free breathing. J. Magn. Reson. Imaging 2013;38:198–205. © 2012 Wiley Periodicals, Inc.</p> </sec> </abstract>