Abstract:
:With the advent of breath-hold MR cardiac imaging techniques, the minimization of TR and TE for oblique planes has become a critical issue. The slew rates and maximum currents of gradient amplifiers limit the minimum possible TR and TE by adding dead-periods to the pulse sequences. We propose a method of designing gradient waveforms that will be applied to the amplifiers instead of the slice, readout, and phase encoding waveforms. Because this method ensures that the gradient amplifiers will always switch at their maximum slew rate, it results in the minimum possible dead-period for given imaging parameters and scan plane position. A GRASS pulse sequence has been designed and ultra-short TR and TE values have been obtained with standard gradient amplifiers and coils. For some oblique slices, we have achieved shorter TR and TE values than those for nonoblique slices.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Atalar E,McVeigh ERdoi
10.1002/mrm.1910320613subject
Has Abstractpub_date
1994-12-01 00:00:00pages
773-7issue
6eissn
0740-3194issn
1522-2594journal_volume
32pub_type
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