Hello:
I have been analyzing the 12 direction DTI data with patients and controls using TBSS. I
used tfce for my final statistical analyses and get predicted results in the controls>patients
contrast. However, when I use the cluster command to parse out the possible clusters in my
data, from which I could pull out the mean FA values, I get this one big cluster that pretty
much encompasses the entire contrast with some other clusters. The way I understand is
that cluster works by combining all the areas with a similar p-value? Given that this cluster
includes the genu of the CC, splenium and the posterior thalamic radiation amongst many
others, it kind of defeats the purpose of pulling out mean FA from more defined clusters. Is
there any other way that I can accomplish this?
One way I was thinking of doing this would be to take the local maxima in the clusters and
creating an ROI around that. But I was wondering what approach do people usually follow
for making an ROI for DTI data? Is it just mostly creating a 10 mm box around the peak
voxel? Any help would be much appreciated.
Sincerely,
-Ruchika
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