Hi - this would depend on exactly what caused the differences in the
first place, and that is worth looking into. However it is quite
likely the case that the B0 images taken with different acquisition
parameters than the rest of the diffusion dataset are not going to be
safely usable.
Cheers.
On 17 Feb 2009, at 12:54, Johnny Zhuang wrote:
> Hi all
>
> Recently, we have been collecting and processing our DTI data with 32
> directions and several separate b0s images (it's recommended that
> every 8
> directions should have one B0 image). Initially, we want to average
> the
> separate b0s together with the b0 of the 4D DTI data. However, after
> some
> analyses, we found that the grayscale intensity range of the
> separate b0s is
> quite different from that of the b0s acquired together with b1s,
> which maybe
> due to the different scanning parameters (eg. TR and TE). Further,
> it is found
> that the relationship between the intensity range of these two kinds
> of b0s is
> nonlinear, which means that we can not simply average them. Is there
> anyone
> who also came across this sort of problem and knows how to fix it?
> Thanks for your help
>
> Many thanks and regards
>
> Johnny
>
> School of Psychiatry
> University of New South Wales
>
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