Abstract:
:This paper describes a technique for characterizing the gradient subsystem of a magnetic resonance (MR) system. The technique uses a Fourier-transform analysis to directly measure the k-space trajectory produced by an arbitrary gradient waveform. In addition, the method can be easily extended to multiple dimensions and can be adapted to measuring residual gradient effects such as eddy currents. Several examples of gradient waveform and eddy-current measurements are presented. Also, it is demonstrated how the eddy-current measurements can be parameterized with an impulse-response formalism for later use in system tuning. When compared to a peak-fitting analysis, this technique provides a more direct extraction of the k-space measurements, which reduces the possibility of analysis error. This approach also has several advantages as compared to the conventional eddy-current measurement technique, including the ability to measure very short time constant effects.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Alley MT,Glover GH,Pelc NJdoi
10.1002/mrm.1910390411subject
Has Abstractpub_date
1998-04-01 00:00:00pages
581-7issue
4eissn
0740-3194issn
1522-2594journal_volume
39pub_type
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