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Inherent insensitivity to RF inhomogeneity in FLASH imaging

✍ Scribed by Danli Wang; Keith Heberlein; Stephen LaConte; Xiaoping Hu

Publisher
John Wiley and Sons
Year
2004
Tongue
English
Weight
368 KB
Volume
52
Category
Article
ISSN
0740-3194

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✦ Synopsis

Abstract

Radiofrequency (RF) field inhomogeneity is an unavoidable problem in MRI, and it becomes severe at high magnetic fields due to the dependence of B~1~ on the sample. It leads to nonuniformities in image intensity and contrast, causing difficulties in quantitative interpretation and image segmentation. In this work, it is observed that with the fast low‐angle shot (FLASH) sequence, which is often used for anatomic imaging and morphometric studies, sensitivity to RF inhomogeneity can be substantially reduced when the same coil is used for both transmission and reception, and an appropriate nominal flip angle is employed. This observation can help us understand the signal behavior of FLASH in the presence of RF inhomogeneity, and provide a guide for selecting parameters in FLASH imaging. Magn Reson Med 52:927–931, 2004. © 2004 Wiley‐Liss, Inc.

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