Automatic Z-shimming Based on A Real-time Feedback Optimization Framework in BOLD-EPI
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چکیده
Fig. 2 The three z-shim images evaluated by real time optimization are combined into a MIP image showed in the 4 column. The MIP image consisted of three z-shim images by traditional z-shimming method is showed in the 5 column. Fig. 1 The comparison of real time optimization and traditional z-shimming sweep. Each spot means the intensity summation of z-shim image. The black star symbol indicates the converged value of red diamonds, and that is near the peak of sweep profile. The real time optimization totally acquires 16 images but only 9 z-shim values are calculated. The proper Δ Mz calculated by our method is -327 / T m ms μ ⋅ and the best ΔMz in global search is -400 / T m ms μ ⋅ . -3000 -2000 -1000
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تاریخ انتشار 2009