Thank you for the input, Roberto.
Thought it might be o.k., but wanted to double-check before tying up processing resources for a couple of days.
Am I correct about the "preserve volumes" (modulation) option, as it applies to preserving EPI and ASL concentrations after high dimensional warping? The VBM8 deformations routine does not provide any guidance on the matter and is clearly written with the assumption that the images being transformed are structural.
Warm regards,
Jeff
---- [log in to unmask] wrote:
> Dear Jeff,
>
> > I have VBM8 segmented (w/ DARTEL high-dimensional warp and
> > non-linear modulation of grey and white maps) a large group of
> > structural images that also have co-registered ASL and EPI series
> > images and in the same voxel dimensions.
> >
> > Any problems in applying the forward transforms to the ASL and EPI
> > data to bring them into atlas space?
>
> Having carried out several studies with ASL, I could not see a
> systematic difference between using the strategy you describe or
> normalizing the EPI average to the EPI template when I looked at it. I
> think both are acceptable. I also think that there is no ASL-specific
> issue here to consider.
>
> Best wishes,
> Roberto Viviani
> Department of Psychiatry, University of Ulm
>
>
>
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