Abstract:
:The fast spin-echo (FSE) sequence is frequently used as a fast data-readout technique in conjunction with other pulse sequence elements, such as in fluid-attenuated inversion-recovery (FLAIR) and double inversion-recovery (DIR) sequences. In order to implement those pulse sequences, an understanding is required of how the longitudinal magnetization evolves during the FSE part of the sequence. This evolution has been addressed to a certain extent by previous publications, but the DIR literature in particular appears to be replete with approximations to the exact expression for the longitudinal magnetization, and several papers contain errors. Equations are therefore presented here for the evolution of the longitudinal magnetization for a FSE readout. These are then applied to calculate the magnetization available immediately prior to the 90 degrees imaging pulse for the FLAIR-FSE and DIR-FSE pulse sequences.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Meara SJ,Barker GJdoi
10.1002/mrm.20541subject
Has Abstractpub_date
2005-07-01 00:00:00pages
241-5issue
1eissn
0740-3194issn
1522-2594journal_volume
54pub_type
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