I am working on comparing tractography from different acquisitions for surgical planning. One of the acquisitions given to me is a q-ball sequence (see gradients table below). A prior post indicated that q-ball support was removed from MRtrix, but before I go off looking at other packages, I thought I’d ask if anyone has used q-ball data for tractography in MRtrix. Currently I get this error (which makes sense):
145: tckglobal dwi.mif wm_response.txt -riso csf_response.txt -riso gm_response.txt -mask mask.mif -niter 1e9 -fod fod.mif -fiso fiso.mif tracks.tck
tckglobal: [ERROR] DWI volumes could not be classified into b-value shells; gradient encoding may not represent a HARDI sequence
Thanks!
-dan
144: mrinfo -dwgrad dwi.mif
0 0 0 0
-0 -0.999838 -0.0180093 100
-0 -0 -1 100
-0.999838 -0 -0.0180093 100
0.707049 -0.707049 -0.0127376 200
0.702398 -0 -0.711784 250
-0 -0.702398 -0.711784 250
-0 0.702398 -0.711784 250
-0.707049 -0.707049 -0.0127376 200
-0.702398 -0 -0.711784 250
0.574484 -0.574484 -0.583041 350
0.574484 0.574484 -0.583041 350
<snip>
0.707099 -0.707099 -0.00477759 900
0.704339 -0 -0.709863 900
-0 -0.704339 -0.709863 900
-0 0.704339 -0.709863 900
-0.707099 -0.707099 -0.00477759 900
-0.704339 -0 -0.709863 900
0.665663 -0.665663 -0.337322 1000
0.664308 -0.332154 -0.669603 1000
0.664308 0.332154 -0.669603 1000
0.665663 0.665663 -0.337322 1000
0.332154 -0.664308 -0.669604 1000
0.332154 0.664308 -0.669604 1000
-0 -0.999988 -0.00499981 1000
-0 -0 -1 1000
-0.332154 -0.664308 -0.669604 1000
-0.332154 0.664308 -0.669604 1000
-0.665663 -0.665663 -0.337322 1000
-0.664308 -0.332154 -0.669603 1000
-0.664308 0.332154 -0.669603 1000
-0.665663 0.665663 -0.337322 1000
-0.999988 -0 -0.00499981 1000