Numerically optimized radiofrequency pulses for robust and low-power cardiovascular T2 preparation at 3T
نویسندگان
چکیده
Radiology, University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland Figure 1 Performance of the tailored pulses. a) Example characteristics of the HS1-derived TR-FOCI pulse. Note that the optimized pulse is broad compared to the standard HS1 (dotted line). b) Slice-excitation profile of the same HS1-derived TR-FOCI pulse. Above a low pulse power of gB1≈200 Hz, the profile has a very sharp transition. c) On-resonance inversion power requirements of the standard and TR-FOCI pulses. Once the HS1 pulse is optimized as a TR-FOCI pulse, it requires power similar to the standard HS8 pulse. d) Robustness of the same pulses to B0 variability at pulse power gB1 = 500 Hz. While the poor original profile of the HS8 pulse is improved after optimization, it is especially the optimized HS1 that has improved robustness. van Heeswijk et al. Journal of Cardiovascular Magnetic Resonance 2014, 16(Suppl 1):P41 http://www.jcmr-online.com/content/16/S1/P41
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