Iterative shimming method for a basic field magnet of a nuclear

Details Iterative shimming method for a basic field magnet of a nuclear Iterative shimming method for a basic field magnet of a nuclear

1993-08-13

1995-02-21

Arana, Louis

Electricity: measuring and testing

Particle precession resonance

Spectrometer components

324319, G01V 300

Patent

active

053919904

ABSTRACT:
To improve the homogeneity of the basic magnetic field generated in a nuclear magnetic resonance tomography unit, an iterative shimming method includes the steps of generating a pulse sequence in the form of a bipolar gradient pulse train in the examination volume, and entering the echo signals which are acquired into a measured matrix. A correlation coefficient of the echo signals of at least a part of the rows of the measurement matrix is formed with respect to a reference row. The shim current through at least one shim coil in the tomography apparatus is then varied in a manner causing the correlation coefficient to increase. These steps are repeated until the correlation coefficient reaches a selected value which is large enough to indicate that an adequate basic field homogeneity has been achieved.

REFERENCES:
patent: 3569823 (1968-10-01), Goley
patent: 4748409 (1988-05-01), Frahm et al.
patent: 4761614 (1988-08-01), Prammer et al.
patent: 4899109 (1990-02-01), Tropp et al.
patent: 4987371 (1991-01-01), Glover et al.
patent: 5006804 (1991-04-01), Dorri et al.
"Aspects of Shimming a Superconductive Whole-Body MRI-Magnet," Frese et al., Proc. of the 9.sup.th Int. Conf. on Magnet Technology, Zurich, Sep. 9-13, 1985, pp. 249-251.
"NMR Imaging Techniques and Applications: A Review," Bottomley, Rev. Sci. Instrum. 53(9), Sep. 1982, pp. 1319-1337.
"Fast, Noniterative Shimming of Spatially Localized Signals. In Vivo Analysis of the Magnetic Field along Axes," Gruetter, J. Mag. Res. vol. 96 (1992), pp. 233-334.

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