Abstract:
:As a high-speed imaging technique based on stimulated echoes single-shot STEAM MRI is insensitive to chemical shift artifacts and magnetic susceptibility differences. The achievable signal-to-noise ratio (SNR) is limited by the fact that high flip angles of the read-out excitation pulses cause a steep decay of the stimulated echo train and therefore degrade the point-spread function of the resulting image. The present work investigates the use of half-Fourier phase encoding which weakens the flip angle constraint by reducing the number of necessary excitations. Single-shot STEAM MRI of the normal human brain at 2.0 T demonstrates that half-Fourier versions either reduce the measurement time by almost a factor of two without sacrificing the SNR or increase the SNR by about 40% while keeping the measurement time constant.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Finsterbusch J,Frahm Jdoi
10.1002/mrm.10090subject
Has Abstractpub_date
2002-03-01 00:00:00pages
611-5issue
3eissn
0740-3194issn
1522-2594pii
10.1002/mrm.10090journal_volume
47pub_type
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