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Multiple echo SSFP sequences

✍ Scribed by Chris T. Mizumoto; Eiji Yoshitome

Publisher
John Wiley and Sons
Year
1991
Tongue
English
Weight
416 KB
Volume
18
Category
Article
ISSN
0740-3194

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✦ Synopsis

Abstract

We report a new type of SSFP imaging sequences for acquiring higher‐order echoes. Spins excited during a cycle have, in a sense, a phase memory such that they can be refocused several cycles down the line, and since the spins are pulsed under a steady‐state condition, the resulting echoes have very complicated T~1~ and T~2~ dependencies. A steady‐state equation, which describes the T~1~ and T~2~ dependencies for the higher‐order echoes, is presented, and the intensity of each echo is calculated and compared with the experimental results. Although the signal intensity of the higher‐order echoes are weaker than the FID or the CE‐FAST echo, these echoes may be used to obtain images with different contrast dependencies previously unobtainable with either of the two signals. © 1991 Academic Press. Inc.

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