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Rapid, fully automatic, arbitrary-volume in vivo shimming

✍ Scribed by Peter Webb; Albert Macovski

Publisher
John Wiley and Sons
Year
1991
Tongue
English
Weight
612 KB
Volume
20
Category
Article
ISSN
0740-3194

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✦ Synopsis

Abstract

MR spectroscopy and many MR imaging methods benefit from a well‐shimmed magnet. We have developed a pulse sequence which enables fast and accurate measurement of three‐dimensional field maps in vivo, and a data analysis package that allows calculation of shim currents to optimally shim arbitrary selected volumes. A data link to the shim power supply allows automatic update of currents. No intervention by the operator is required. Typical in vivo shimming time is less than 5 min. Performance analysis, phantom, and in vivo results are presented. © 1991 Academic Press, Inc.

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