Abstract:
PURPOSE:Respiratory organ motion is still the major challenge of various image-guided treatments in the abdomen. Dynamic organ motion tracking, necessary for the treatment control, can be performed with volumetric time-resolved MRI that sequentially acquires one image and one navigator slice. Here, a novel imaging method is proposed for truly simultaneous high temporal resolution acquisition. METHODS:A standard balanced steady state free precession sequence was modified to simultaneously acquire two superimposed slices with different phase cycles, namely an image and a navigator slice. Instead of multiband RF pulses, two separate RF pulses were used for the excitation. Images were reconstructed using offline CAIPIRINHA reconstruction. Phantom and in vivo measurements of healthy volunteers were performed and evaluated. RESULTS:Phantom and in vivo measurements showed good image quality with high signal-to-noise ratio (SNR) and no reconstruction issues. CONCLUSION:We present a novel imaging method for truly simultaneous acquisition of image and navigator slices for four-dimensional (4D) MRI of organ motion. In this method, the time lag between the sequential acquisitions is eliminated, leading to an improved accuracy of organ motion models, while CAIPIRINHA reconstruction results in an improved SNR compared with an existing 4D MRI approach.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Celicanin Z,Bieri O,Preiswerk F,Cattin P,Scheffler K,Santini Fdoi
10.1002/mrm.25134subject
Has Abstractpub_date
2015-02-01 00:00:00pages
669-76issue
2eissn
0740-3194issn
1522-2594journal_volume
73pub_type
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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