Imaging of the active B1 field in vivo.

Abstract:

:The authors describe a method for accurate in vivo multislice imaging of the active component of the B1 field which is based on a previously proposed method, which uses the signal intensity ratio of two images measured with different excitation angles, and a repetition time TR 5 > or = 5 T1. The new method essentially reduces repetition and scan time by means of an additional compensating pulse. The suppression of T1 effects by this pulse are verified with simulations and measurements. Further investigations concerned the influence of slice selective excitation and magnetization transfer in multislice imaging to the B1 field determination. The stability and accuracy of the presented method is shown by several phantom and in vivo measurements. With the described method the active B1 field can be determined in vivo in 23 cross-sections in less than 6 min.

journal_name

Magn Reson Med

authors

Stollberger R,Wach P

doi

10.1002/mrm.1910350217

subject

Has Abstract

pub_date

1996-02-01 00:00:00

pages

246-51

issue

2

eissn

0740-3194

issn

1522-2594

journal_volume

35

pub_type

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