Hello All,
With help from this support forum I have been able to gradient field map (GFM) correct my DTI data (both before and after ECC). However, I do have a couple of concerns/questions.
Concern 1. Both GFM corrected images appear to have some interpolation issues that impact the clarity of the images (they are not as crisp as my non-GFM corrected images, S1_FA.nii.gz files created after DTIFIT). This is concerning to me. Specifically, I am curious as to how this might quantitatively impact my images (two interpolations with GFM correction versus one interpolation without).
Concern 2. Although my frontal regions look relatively better, my temporal lobes appear to take a big hit (especially when viewing mean_FA images or any images following tbss_3_postreg).
Q1. Is it really advantageous to GFM correct DTI data?
Q2. Am I sacrificing the quality of other cortical structures in an effort to correct for field inhomogeneities in frontal regions?
Cheers!
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