Dear Sourena,
> Should the topup approach be considered superior to fieldmap
> correction regarding (single-band) fMRI?
if you are only getting a single pair for calculating a fieldmap I don’t think it is superior to a “traditional” fieldmap. It is mainly just another way of obtaining the field.
> How serious is the effect of gradient thermal state on fMRI/DTI
> signals specially when the scanner has just started its daily job?
> Does there exist some guideline to adhere?
I am not sure what you mean by “gradient thermal state”. Are you talking about the gradual heating of the gradients during a long run? If so, I don’t think it is a problem for fMRI. Anything slow and gradual tend to be regressed out anyway.
For DTI I don’t know. Maybe someone else has some experience?
Jesper
>
> Thanks in advance,
> Sourena
|