Abstract：
:More than a dozen Nuclear Magnetic Resonance (NMR) imaging methods have been described using different radio-frequency pulse sequences, magnetic field gradient variations, and data processing. In order to have a theoretical understanding in the most general case, we have conceived a computer program for the simulation of NMR imaging techniques. The algorithm uses the solution of the Bloch equations at each point of a simulated object. The direction of every elementary magnetic moment is computed at each instant, and stored in an array giving the global signal to be processed, whatever the pulse and gradient sequence. To test the validity of this program, we have simulated some well-known experimental results. Some applications are presented which contribute to the understanding of image distortions and to techniques such as selective radio-frequency pulse or oscillating gradients. This program can be used to unravel physical and technological causes of image distortions, to have a "microscopic" look at any parameter of an experiment, and to study the contrast given by various NMR imaging techniques as a function of the three NMR parameters, i.e., the hydrogen nuclei density rho and the relaxation times T1 and T2.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Bittoun J,Taquin J,Sauzade Mdoi
10.1016/0730-725x(84)90065-1subject
Has Abstractpub_date
1984-01-01 00:00:00pages
113-20issue
2eissn
0730-725Xissn
1873-5894pii
0730-725X(84)90065-1journal_volume
2pub_type
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