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RF inhomogeneity compensation in structural brain imaging

✍ Scribed by R. Deichmann; C.D. Good; R. Turner

Publisher
John Wiley and Sons
Year
2002
Tongue
English
Weight
473 KB
Volume
47
Category
Article
ISSN
0740-3194

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✦ Synopsis

Abstract

Three‐dimensional T~1~‐weighted magnetization‐prepared rapid gradient‐echo (MP‐RAGE) sequences with centric phase encoding (PE) in the inner loop provide structural brain images with a high spatial resolution and high tissue contrast. A disadvantage of this sequence type is the susceptibility to inhomogeneities of the radiofrequency (RF) coil, which may result in poor image contrast in some peripheral regions. A special excitation pulse is presented which compensates for these effects in both the head/foot and anterior/posterior directions. This pulse has a duration of only 1.3 ms and is thus compatible with the short repetition times (TRs) required for MP‐RAGE imaging. It is shown experimentally that images acquired with the compensation pulse may be segmented without using intensity correction algorithms during data postprocessing. Magn Reson Med 47:398–402, 2002. © 2002 Wiley‐Liss, Inc.

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