Jon-Fredrik Nielsen1,
Daehyun Yoon2, Neal Anthony Hollingsworth3, Katherine
Lynn Moody4, Mary Preston McDougall3,4, Steven M.
Wright3,4, Douglas C. Noll1
1Biomedical Engineering,
University of Michigan, Ann Arbor, MI, USA; 2Electrical
Engineering & Computer Science, University of Michigan; 3Electrical
& Computer Engineering, Texas A&M University; 4Biomedical
Engineering, Texas A&M University
In fast-recovery (FR) or driven-equilibrium steady-state imaging, the magnetization is tipped back toward the longitudinal axis at the end of each repetition interval (TR), with the aim of maximizing the acquired signal. Conventional FR imaging requires one or more spin-echo refocusing pulses, and hence heavy RF deposition. With the use of parallel RF transmission and 3D RF pulse design, it may be possible to replace the conventional spin-echo pulse train with a small-tip excitation pulse followed by a small-tip recovery (tip-up) pulse. We present a simple and effective approach for jointly optimizing the excitation and recovery pulses such that the residual (unwanted) transverse magnetization after the tip-up pulse is minimized.
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