This folder cointains published protocols for different CEST applications. In each subfolder you can find the .seq-file containing the sequence definition.
In addition, the subfolder contain a short description, plot and matlab and python files used to generate the .seq-file.
general pulseq-CEST preparation definitions are as follows
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defs.n_pulses = 36 ; % number of pulses
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defs.tp = 50e-3 ; % pulse duration [s]
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defs.td = 5e-3 ; % interpulse delay between pulses[s]
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defs.Trec = 3.5 ; % recovery time [s]
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defs.Trec_M0 = 3.5 ; % recovery time before M0 [s]
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defs.M0_offset = -300 ; % m0 offset [ppm]
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defs.DCsat = (defs.tp)/(defs.tp+defs.td); % duty cycle
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defs.offsets_ppm = [seq_defs.M0_offset -4:0.25:4]; % offset vector [ppm]
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defs.num_meas = numel(defs.offsets_ppm) ; % number of repetition
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defs.Tsat = defs.n_pulses*(defs.tp+defs.td) - ... seq_defs.td ; % saturation time [s]
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defs.FREQ = 127.7292 ; % Approximately 3 T
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defs.B0 = defs.FREQ/(seq.sys.gamma*1e-6); % Calculate B0
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defs.seq_id_string = seqid ; % unique seq id
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defs.B1pa = 1.78; % mean sat pulse B1 [uT] B1pa*gamma=flip_angle
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defs.B1rms = 3.7 ; % B1rms, this gets calculated and is typically not used as input.
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defs.spoiling = 1; % 0=no spoiling, 1=before readout, Gradient in x,y,z
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defs.TI = [10 6 5 4 3 2.5 2 1.5 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1]; % inversion time before ADC, for T1 mapping sequences