资 源 简 介
Gradient Unwarping Package for Numpy/Python
Goal
To correct for image distortions in MRI data due to non-linearity of the magnetic fields from the imaging gradient coils.
Method described in
Jovicich J, Czanner S, Greve D, Haley E, Kouwe A, Gollub R, Kennedy D, Schmitt F, Brown G, MacFall J, Fischl B, Dale A. Reliability in Multi-Site Structural MRI Studies: Effects of Gradient Non-linearity Correction on Phantom and Human Data. NeuroImage NeuroImage (Apr 1;30(2):436-43, 2006)
Outline of steps involved
Obtain from your local Siemens or GE vendor the spherical harmonics expansion that represents the gradient coils used in the MRI system you want to correct. This is a text file with proprietary information.
We provide a script (gradient_unwarp_converter.pl ) that reads the spherical harmonics text file and writes out the coefficients in a standard format (for example,
