Abstract:
:Breathing motion is one of the main sources of artifacts in MRI acquisitions that can severely impair diagnosis. In MRI with continuously moving table, the application of common motion compensation approaches such as breath holding or the synchronization of the measurement with the breathing motion can be problematic. In this study, a technique for the reduction of breathing-motion artifacts for MRI with continuously moving table is presented, which reconstructs motion-consistent volumes from data acquired during free breathing. Axial images are acquired rapidly compared to the period of the breathing motion and consistently combined using a combination of rigid and nonrigid slice-to-volume registration. This new technique is compared to a previously reported artifact reduction method for MRI with continuously moving table that is based on the same acquisition scheme. While the latter method only suppresses ghosting artifacts, the new technique is shown to additionally reduce blurring, misregistrations, and signal cancellations in the reconstructed images.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Honal M,Leupold J,Huff S,Baumann T,Ludwig Udoi
10.1002/mrm.22162subject
Has Abstractpub_date
2010-03-01 00:00:00pages
701-12issue
3eissn
0740-3194issn
1522-2594journal_volume
63pub_type
杂志文章abstract::Frequency-modulated (FM) pulses have practical advantages for spin-echo experiments, such as the ability to produce a broadband pi rotation, with an inhomogeneous radiofrequency (RF) field. However, such use leads to a nonlinear phase of the transverse magnetization, which is why FM pulses like the hyperbolic secant (...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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更新日期:2013-07-01 00:00:00
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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