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b1-correction [2015/12/04 15:04] (current)
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 +====== Correction of B1 inhomogeneity artifacts in CEST images ======
 +{{ :​b1_corr.png?​direct&​200|}}
 +Here you find a B1-correction algorithm as published in **Windschuh et al. (2015), NMR Biomed., 28(5):​529-37. ​ [[http://​onlinelibrary.wiley.com/​doi/​10.1002/​nbm.3283/​abstract|doi:​ 10.1002/​nbm.3283]]**. ​
 + 
 +Dowload zipped Matlab implementations [[https://​github.com/​cest-sources/​B1_correction/​archive/​master.zip|here]] or find the package on [[https://​github.com/​cest-sources/​B1_correction/​]]
 +
 +====== ​ Tutorial ======
 +There are two functions, **Z_B1_correction** and **contrast_B1_correction**,​ which both require data of several CEST acquisitions with different B1. Both reconstruct either Z-spectrum stacks or contrast stacks at the B1 values given by **B1_output**.
 +
 +<code matlab>
 +function [Z_stack_corr] = Z_B1_correction(Z_stack,​rel_B1map,​B1_input,​B1_output,​SEGMENT,​fit_type,​B1_input_index)
 +% [Z_stack_corr] = Z_B1_correction(Z_stack,​rel_B1map,​SEGMENT_2D,​B1_input,​fit_type,​B1_input_index,​B1_output)
 +% output: B1 corrected Z-stack (5D-stack)
 +% input: ​   Z_stack = 5D-stack of Z-spectra (y,​x,​z,​offset,​B1)
 +%           ​rel_B1map = relative B1map
 +%           ​B1_output = output B1 (scalar or vector)
 +%           ​SEGMENT = voxel/pixel mask for evaluation
 +%           ​fit_type = fit or interpolation type
 +%           ​B1_input_index = index vector of B1 samples that should be used
 +%           for correction
 +%
 +</​code>​
 +
 +<code matlab>
 +function [corr_img]=contrast_B1_correction(img,​rel_B1map,​B1_input,​B1_output,​SEGMENT_2D,​fit_type,​B1_input_index)
 +% [corr_img]=contrast_B1_correction(img,​rel_B1map,​B1_input,​B1_output,​SEGMENT_2D,​fit_type,​B1_input_index)
 +% output: B1 corrected images (2D or 3D-stack) (x,y,B1)
 +% input: ​   img = 3D-stack of images (x,y,B1) which are used for B1-correciton
 +%           ​rel_B1map = relative B1map
 +%           ​B1_output = output B1 (scalar or vector)
 +%           ​SEGMENT_2D = pixel mask for evaluation
 +%           ​fit_type = fit or interpolation type
 +%           ​B1_input_index = index vector of B1 samples that should be used
 +%           for correction
 +</​code>​
 +{{ :​logo_dkfz.png?​direct&​180|powered by DKFZ}}
  
b1-correction.txt · Last modified: 2015/12/04 15:04 (external edit)