QMRITools`
QMRITools`
DixonReconstruct
DixonReconstruct[{real,imag},echo]
reconstruxt Dixon data with initital guess b0 = 0 and T2star = 0.
DixonReconstruct[{real,imag},echo,{b0}]
reconstructs Dixon data with intitial guess T2star = 0.
DixonReconstruct[{real,imag},echo,{b0,t2}]
reconstructs Dixon data with t2star and B0.
DixonReconstruct[{real,imag},echo,{b0,t2,ph0}]
reconstructs Dixon data with initial phase.
DixonReconstruct[{real,imag},echo,{b0,t2,ph0,phb}]
reconstructs Dixon data with bipolar phase . Output is {{watF,fatF},{watSig,fatSig},{inphase,outphase},{{b0, ph0, phbphb}},{r2, t2}},itterations}. The fractions are between 0 and 1, the B0 field map is in Hz and the T2start map is in ms.
is based on DOI: 10.1002/mrm.20624 and 10.1002/mrm.21737 (10.1002/nbm.3766).
Details
- The following options can be given:
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DixonPrecessions 1 DixonPrecessions is an option for DixonReconstruct. Defines the rotation of the signal {-1,1} default is -1. DixonFieldStrength 3 DixonFieldStrength is an option for DixonReconstruct. Defines the fieldstrengths in Tesla on which the data was acquired. DixonNucleus "1H" DixonNucleus is an option for DixonReconstruct. Defines the nucleus for which the reconstruction is performed. DixonFrequencies {{0.}, {-3.81, -3.4, -3.12, -2.67, -2.45, -1.94, -0.63, -0.4, 0.52, 0.62}} DixonFrequencies is an option for DixonReconstruct. Defines the frequencies in ppm of the fat peaks being used. DixonAmplitudes {{1}, {0.089, 0.577, 0.059, 0.093, 0.059, 0.013, 0.02, 0.02, 0.01, 0.059}} DixonAmplitudes is an option for DixonReconstruct. Defines the relative amplitudes of the fat peaks being used. DixonRelaxivity {{35}, {130, 135, 85, 95, 100, 90, 100, 100, 85, 85}} DixonRelaxivity is an option for DixonReconstruct. Defines the T2 relaxation times of the fat peaks being used. Is only used if DixonFixT2 is set to True. DixonIterations 10 DixonIterations is an option for DixonReconstruct. Defines the maximum itterations the fit can use. DixonTollerance 1 DixonTollerance is an option for DixonReconstruct. Defines at which change per itteration of b0 and R2star the ittarative methods stops. Default value is 0.1. DixonMaskThreshhold 0.1 DixonMaskThreshhold is an option for DixonReconstruct. Defines at which threshhold the dixon reconstruction considers a voxel to be background noise. Defualt values is 0.05. DixonFilterInput False DixonFilterInput is an option for DixonReconstruct. If True the input b0 and T2star values are smoothed using a gaussian kernel. DixonFilterOutput True DixonFilterOutput is an option for DixonReconstruct. If True the out b0 and T2star values are smoothed Median filter and lowpassfiltering after which the water and fat maps are recomputed. DixonFilterSize 1 DixonFilterSize is an option for DixonReconstruct. Defines the number of voxel with which the input b0 and T2star values are smoothed. DixonFilterType "Median" DixonFilterType is an option for DixonReconstruct. FilterType can me "Median" or "Laplacian". DixonPhases {True, True, False, False, False} DixonPhases is an option for DixonReconstruct. It defines which phases to fit within the model. The order is {T2*, B0, bipolar, initial, bipolar}. DixonClipFraction False DixonClipFraction is an option for DixonReconstruct. If set True the fat fraction is clipped between 0 and 1. DixonCorrectT1 False DixonCorrectT1 is an option for DixonReconstruct. To perform T1 correction provide the TR and FA as a list, {TR, FA}. TR is in ms and FA in degrees. DixonFixT2 False DixonFixT2 is an option for DixonReconstruct. If set to true the R2' is fitted rather then the R2*. This is done by fixing T2-water to 30ms and T2-fat to 100ms. DixonConstrainPhase False DixonConstrainPhase is an option for DixonReconstruct. If set True everything is fitted as real values. MonitorCalc False MonitorCalc is an option for many processing functions. When true the proceses of the calculation is shown. DixonFitPhase False DixonFitPhase is an option for DixonReconstruct. If set to True the phase maps are fitted using polinomial functions.