Microsoft Word - ISMRM2005-003424.DOC
نویسندگان
چکیده
P. E. Larson, D. G. Nishimura, J. M. Pauly Electrical Engineering, Stanford University, Stanford, CA, United States Introduction: Ultra-short echo time (UTE) imaging has recently become of interest for possible clinical applications [1,2]. Long-T2 species dominate UTE images if they are not suppressed. We introduce a new set of long-T2 suppression pulses designed with the Shinnar-Le Roux (SLR) pulse design algorithm [3]. They are low-amplitude, longduration RF pulses that have improved off-resonance bandwidths over previous hard long-T2 suppression pulses [4]. We also have designed a long-T2 suppression pulse that includes fat-saturation. Theory: We solved the Bloch equation for MZ at conclusion of a RF pulse, ω1(t). We included T2 decay but not T1 decay and assumed T2 is much shorter than the pulse duration to obtain the following result:
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