Marcus Bjrk1, R. Reeve Ingle2, Jolle K. Barral3, Erik Gudmundson4, 5, Dwight G. Nishimura2, Petre Stoica1
1Department of Information Technology, Uppsala University, Uppsala, Sweden; 2Electrical Engineering, Stanford University, Stanford, CA, United States; 3HeartVista, Inc., Los Altos, CA, United States; 4Centre for Mathematical Sciences, Lund University, Lund, Sweden; 5Signal Processing Lab, ACCESS Linnaeus Center, KTH Royal Institute of Technology, Stockholm, Sweden
Banding artifacts are a major issue in bSSFP. Several images with equally spaced phase increments are typically acquired to mitigate this issue. However, to the best of our knowledge, no theoretical justification exists for such a distribution of phase increments. We derived the Cramr-Rao bound (CRB) from the bSSFP signal model and optimized the phase increments distribution to minimize the maximum CRB over all possible off-resonances. We show that the worst-case CRB is minimized when using equally spaced phases, and that the resulting performance is relatively close to the optimal, had the off-resonance been known a priori.
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