[Mristudio-users] FA=1 and more strange Dtistudio problems, please help

[me]

Dear Dtistudio experts,

I am a newbie user of this software who have encountered very confusing
problems that I don't understand how to solve. Please see the description
below. I keenly look forward to your help! Thank you very much for tutoring.



Detailed data processing procedure:
1. Acquisition: Siemens Trio 3.0T with Mosaic format
Parameters: diffusion directions=20, slices=25, average=2, number of b-value
is 6 plus b0.
2. Extract different b-value subfiles using matlab
3. Raw data converted from DICOM to NIfTI using dcm2niigui.exe, resulting in
four sets of files: **.img,  **.hdr,  **.bvec,  **.bval.
3. Adjust **.bval file to the right format suitable for DTIstudio
4. Load **.img file to DTIstudio à MRI View 3D, choose ‘image file format’
as ‘Analyze’, then automatic image registration (AIR), the data saved as
**.dat
5. Opening DTI mapping, select Philips REC format, add the **.dat file
generated in Step 4. Copy the gradient table generated in Step 3
6. Calculate the tensor, color map, etc

Question1:
Is my data processing procedure correct?

Question2:
Under AIR condition, after sensor calculation and checking ‘Anisotropy-FA’,
I found that slice0 shows nothing, as if the information in slice0 is
lost.The last slice shows apparently wrong FA because many pixels value
FA=1. But the slices between these two slices seem to be normal. If I don’t
do the AIR, slice0 information is not lost , and slice24 shows normal FA
values.


Sincerely,
Chunxiang
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