Hi,
I had attached a movie file from a DTI sequence with 30 directions and 3 averages but it didnt go through. There is slice dropout within a brain volume for certain directions. i.e 3-4 slices within the brain volume have almost no signal while other slices are ok. It looks like head motion but i'm not sure. Is someone enlighten me with the cause of this artifact? Also if the artifact takes place in only one of the repetitions can i still use the dataset by discarding the bad repetition ( and accordingly adjusting the bvecs and bvals)?
What if the artifact is spread out and i want to remove for eg: volumes for 2 directions in the 1st repetition and volumes for 3 directions in the 2nd?
In such a case can i still get valid results ( although lower SNR for estimation for some directions)?
-Vish
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