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standard_cest_protocols [2020/06/15 11:53] (current)
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 +====== 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
 +
 +
 +
 +
  
standard_cest_protocols.txt · Last modified: 2020/06/15 11:53 (external edit)