Abstract:
:A new spherical navigator echo (SNAV) registration technique is presented. This technique starts by collecting a set of SNAV templates at a reference position. These templates are acquired by rotating the gradient system to result in rotation angles that uniformly cover a predefined range of rotation. The rotation angles between an unknown physically transformed position and the reference position are subsequently determined by finding the template with the lowest sum of squared differences with SNAV at the transformed position. Translations are calculated from the phase differences between the best-match SNAV template and the SNAV acquired at the transformed position. In comparison with the conventional SNAV registration technique, the proposed technique is noniterative, robust, and can detect 3-dimensional rigid body motion in less than 50 msec. The technique was verified with phantom and in vivo experiments, which demonstrated subdegree rotational and submillimeter translational accuracy over a range of simultaneous ±20° and ±10° mm of motion.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Liu J,Drangova Mdoi
10.1002/mrm.22629subject
Has Abstractpub_date
2011-02-01 00:00:00pages
506-14issue
2eissn
0740-3194issn
1522-2594journal_volume
65pub_type
杂志文章abstract::Since contrast in magnetic resonance imaging (MRI) is so sensitive to the magnetic relaxation rates of tissue protons, the use of paramagnetic ions to alter contrast in a tissue-specific fashion is an alluring prospect. The influence of these ions on the proton relaxation rates in homogeneous solutions is known to var...
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
pub_type: 临床试验,杂志文章
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journal_title:Magnetic resonance in medicine
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更新日期:2010-07-01 00:00:00
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更新日期:2010-04-01 00:00:00
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