Dear FSL list,
I have a region of interest from TBSS analyses of FA images and would like
to find the mean diffusivity (MD) values for the same region. To get the
MD in the same space, I am running tbss_1_preproc (after re-naming them
the same as the FA), and then tbss_non_FA. tbss_1_preproc requires a
scaling argument -- my understanding is that the goal is to get the range
on the order of 0 to 10,000. Here are a few examples ranges of our MD
images:
.00046336 to .0021267
.00063775 to .0022076
.00058721 to .0018281
So, should I be using something like 5,000,000 for scaling? Is it a
little arbitrary -- what's the effect of 5,000,000 versus 4,800,000 in
this situation? What will be the meaning of the values after this re-
scaling? Will the values relate in any way to the usual units for
diffusivity (something like x10^3 mm2/s)?
Thank you,
Dana
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