Dear guys,
Currently, I am working on finding the different of FA image between two populations.
For each object, the ROI is defined by a sphere with radius R = 25mm (center coordinate as following - in subject space (MPRAGE image) , not in MNI space)
subject id x y z
sub 1 165 89 132
sub 2 151 111 150
sub 3 153 110 155
sub 4 160 112 132
.... ... ... ...
sub n 162 139 103
To run the TBSS on these ROI, we will create a mask by union all of these ROI in MNI space. Two step as bellow:
Step 1. Convert (x,y,z) in subject space to MNI space, called (x',y',z'):
Step 2. Union all of the new ROI in MNI space <(x',y',z'), R> to create a mask
Because I am just a babier in FSL, so could you please give me some feedbacks about
Step 1.
1.1 echo "X Y Z" | std2imgcoord -img <(MPRAGE image filename> -std <FSL/MNI256_1mm image> -mm -
by using this command, could I can get the new coordinate in MNI space? called (x',y',z')
1.2 supposed I got (x',y',x'), how I can create ROI <(x',y',z'),R>. Or I have to open fslview and draw it manually? Is there any command to create ROI?
Step 2.
Assuming that I got n ROIs in MNI space (each of them respectively to each subject), what is the way I can union all of it to create a mask of ROI?
Thank you very much for your help.
All of your advisement are very appreciated.
Best,
Thien Bao
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