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standard_cest_protocols

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 — standard_cest_protocols [2020/06/15 11:53] (current) Line 1: Line 1: + ====== Standard CEST protocols ====== + + B1 definitions here are the flip angle equivalent (pure FA), thus the average B1 of a **single** saturation pulse. + This also means that the flip angle of each saturation pulse is directly given by FA = B1·γ·t_p + + t_p  = duration of a single saturation pulse, + t_sat = total time of the saturation pulse train + + + ---- + + ===== 3T APT ===== + + ====APTw_1 : APT-weighted, low DC, t_sat=1.8s (//GLINT//) ==== + * pulse shape = Gaussian + * B1 = 2.22 µT + * n = 20 + * t_p = 50 ms + * t_d = 40 ms + * => DC = 0.55 and t_sat = n*(t_p+t_d) = 1.8 s + * T_rec = 2.4/12 s (saturated/M0) + + total acquisition time (depends on the readout) : approximately 3min24s for snapshot-GRE + + + ====APTw_2  : APT-weighted, low DC, t_sat=0.8s (//HDAPTTRIO//) ==== + + * pulse shape = RECT + * B1 = 2 µT + * n = 5 + * t_p = 100 ms + * t_d = 72 ms + * => DC = 0.58 and t_sat = n*(t_p+t_d) = 860 ms + * T_rec = 2 s + * measurements= 17 + + Δω [ppm] = -300, 4, -3.75, -3.75, -3.5, -3.5, -3.25, -3.25, -3, 3, 3.25, 3.25, 3.5, 3.5 3.75, 3.75, 4 + + ====APTw_3 : APT-weighted, high DC, t_sat=0.8s (//HDAPT//) ==== + + * pulse shape = RECT + * B1 = 2 µT + * n = 8 + * t_p = 100 ms + * t_d = 5 ms + * => DC = 0.95 and t_sat = n*(t_p+t_d) = 840 ms + * T_rec = 2 s + * measurements= 17 + + Δω [ppm] = -300, 4, -3.75, -3.75, -3.5, -3.5, -3.25, -3.25, -3, 3, 3.25, 3.25, 3.5, 3.5 3.75, 3.75, 4 + + + + + ---- + + + ===== 3T Multi-Pool (MP)  -  low power -  selective amide and NOE protocols ===== + + + ==== MP_1 : low DC (//GLINT//) ==== + + * pulse shape = Gaussian + * B1 = 0.6 µT (first scan),  B1 = 0.9 µT (second scan) + * n = 80 + * t_p = 20.48 ms + * t_d = 20 ms + * => DC = 0.5 and t_sat = n*(t_p+t_d) = 3.2 s + * T_rec = 0 ms + * measurements = 54 + + Δω [ppm] = [ -300, -100, -50, -40, -30, -20, -10, -9.5, -9,-8.5,-8,-7.5,-7,-6.5,-6,-5.5,-5,-4.5,-4,-3.5,-3,-2.5,-2,-1.5,-1,-0.5,-0.25,0,0.25,0.5,1,1.5,2,2.5,3,3.5,4,4.5,5,5.5,6,6.5,7,7.5, 8,8.5,9,9.5,10,20,30,40,50,100 ] + + total acquisition time (depends on the readout) : approximately 5min20s for snapshot-GRE + + ==== MP_2 : high DC (//HD//) ==== + + * pulse shape = Gaussian + * B1 = 0.6 µT (first scan),  B1 = 0.9 µT (second scan) + * n = 148 + * t_p = 20 ms + * t_d = 5 ms + * => DC = 0.8 and t_sat = n*(t_p+t_d) = 3.7 s + * T_rec = 0/12 s (saturated/M0) + * measurements = 57 + + Δω [ppm] = 250, 200, 150, 110, 80, 60, 45, 35, 28, 22, 17, 13, 10, 7.5, 6, 5, 4.5, 4, 3.5, 3, 2.5, 2, 1.5, 1.2, 0.9, 0.7, 0.5, 0.3, 0, −0.3, −0.5, −0.7, −0.9, −1.2, −1.5, −2, −2.5, −3, −3.5, −4, −4.5, −5, −6, −7.5, −10, −13, −17, −22, −28, −35, −45, −60, −80, −110, −150, −200, −250 + + total acquisition time (depends on the readout) : approximately 7min34s per B1 for snapshot-GRE + + + ===== 7T Multi-Pool (MP)  -  low power -  selective amide and NOE protocols ===== + + ==== MP_1 (//GUFI TH2//) ==== + + * pulse shape = Gaussian + * B1 = 0.6 µT (first scan),  B1 = 0.9 µT (second scan) + * n = 120 + * t_p = 15ms + * t_d = 10 ms + * => DC = 0.6 and t_sat = n*(t_p+t_d) = 3.0 s + * T_rec = 0/12 s (saturated/M0) + * measurements = 56 + + Δω [ppm] = [-300 + -100 + -50 + -20 + -12 + -9 + -7.25 + -6.25 + -5.5 + -4.7 + -4 + -3.3 + -2.7 + -2 + -1.7 + -1.5 + -1.1 + -0.9 + -0.6 + -0.4 + 0 + 0.4 + 0.6 + 0.95 + 1.1 + 1.25 + 1.4 + 1.55 + 1.7 + 1.85 + 2 + 2.15 + 2.3 + 2.45 + 2.6 + 2.75 + 2.9 + 3.05 + 3.2 + 3.35 + 3.5 + 3.65 + 3.8 + 3.95 + 4.1 + 4.25 + 4.4 + 4.7 + 5.25 + 6.25 + 8 + 12 + 20 + 50 + 100 + -300 + ] + + + total acquisition time (depends on the readout) : approximately 6:40s per B1 for snapshot-GRE + + + + 