Abstract:
:Susceptibility artifacts and transmission radio frequency (RF) field (B(1) +) inhomogeneity are major limitations in high-field gradient echo MRI. Previously proposed numerical 2D spectral-spatial RF pulses have been shown to be promising for reducing the through-plane signal loss susceptibility artifact by incorporating a frequency-dependent through-plane phase correction. This method has recently been extended to 4D spectral-spatial RF pulse designs for reducing B(1) + inhomogeneity as well as the signal loss. In this manuscript, we present simple analytical pulse designs for constructing 2D and 4D spectral-spatial RF pulses as an alternative to the numerical approaches. The 2D pulse capable of exciting slices with reduced signal loss and is lipid suppressing. The 4D pulse simultaneously corrects signal loss as well as the B(1) + inhomogeneity from a body coil transmitter. The pulses are demonstrated with simulations and with gradient echo phantom and brain images at 3T using a standard RF body coil. The pulses were observed to work well for multiple slices and several volunteers.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Yang C,Deng W,Stenger VAdoi
10.1002/mrm.22725subject
Has Abstractpub_date
2011-02-01 00:00:00pages
370-6issue
2eissn
0740-3194issn
1522-2594journal_volume
65pub_type
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