Tractography, Tolerance and number of tracts
Maryam Shapourjani
Hello Dear Frank,
I hope you are doing well.
My work focuses on dMRI association pathways in term-born neonates between 37 and 44 weeks of age.
- In the tractography batch step of the software, three default values are entered for tolerance: 22, 24, and 30.
a. Is it necessary to enter three values in this section, or is it also possible to enter only one value?
b. Based on your answer to question (a), for tractography of neonatal data focused on analyzing neonatal shape metrics and modeling the development of these features with age, would you recommend using a single tolerance value or three values?
- Regarding the number of tracts extracted for each pathway, you mentioned that at least 2,000 tracts should be extracted for each pathway in order to conclude that the number of tracts is sufficient to cover the region of interest.
a. Does this also apply to neonatal data, considering differences in tract development between 37 and 44 weeks of age? For example, should at least 2,000 tracts be extracted for both a 37-week-old neonate and a 44-week-old neonate?
b. Does this criterion apply to all association pathways, or are there pathways for which a different minimum number of streamlines would be more appropriate?
Thank you very much for your time and guidance.
Best regards,
Maryam Shapourjani