Dear FSL-experts,
I am wondering about the topup-eddy tools in FSL. Have used
eddy_correct before with older "b=1000-data". Now I am going to
collect some high-bvalue data, well one-shell with b=3000. My patient
population could be prone to some motion, so I need motion correction.
The DWI data is going to be used for fibre tracking of the optic
radiation with some HARDI-technique, so I will aim for b-value around
3000. Can fit in 60 gradient directions, and would not want to collect
any unnecessary b0:s.
I have not set the protocol. I have the possibility to change the
PE-blip directions and to tailor a gradient scheme.
Some questions:
How does topup-eddy work for higher b-values. Enough signal/contrast
in the images with b=3000 data for distortion-, eddy- and motion
correction? Any experience of topup-eddy at these b-values?
How many b0:are needed for topup? Do eddy also use the b0:s?
Is it still advisable to use a twice-refocused SE to limit eddy
currents? Or can I omit this and go for shorter TE and hope that eddy
sorts it?
Cheers,
Finn Lennartsson
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