When performing tract-based analysis, I met a problem that I couldn’t find the option to set the minimum threshold of streamline number such as 5 streamlines. Or, is it only accessible when the track is transformed into fixel-wise?
Another question, do I need to set the threshold of FOD amplitude again when transforming the tract into fixel-wise (though I have set cut-off FOD amplitude = 0.1 during the step of generating whole-brain tractogram)?
I read the method from this paper: doi: 10.1093/cercor/bhy348
“we extracted these ﬁber bundles individually from the template tractogram…The streamlines corresponding to these bundles of interest were then concatenated together and used to generate a ﬁxel analysis mask that included only those ﬁxels through which at least 5 streamlines passed and that had an FOD amplitude of at least 0.1…”
Can you help me to make through this step?