On Monday 30 October 2006 21:19, Benedicte Descamps wrote:
> Hi,
Hi again,
I got nervous after your emails and tested this with a epi2d_diff sequence on
an Allegra. (Have to look for the release number but I think it's the most
recent). Patient position was head-first suppine. Of course I am not totally
sure if the mosaic epi2ds are the same.
What I got.
Numbering starts ventral so 1->N is F->H
Ascending is also 1->N so different from Benedicte's Posting
Interleaved is indeed
1:2:N 2:2:N-1 for odd total slice numbers and
2:2:N 1:2:N-1 if the total slice number is even.
I am also about to ask our Siemens support for help here.
Regards and Thanks,
Roland
> Last month, our TRIO system has been upgraded. We found out that, if the
> acquisition parameter is set to "ascending", the acquisition happens from
> Start to end (see "help" on console) . What is Start? That depends on the
> patient registration: if you register a subject's position as "head first -
> supine", then "start" is top of the head. So scanning "ascending" means:
> H-->F, although you've set the slice numbering from F-->H!!
>....
> All the best with this issue!
> Benedicte
> Citeren Darren G <[log in to unmask]>:
> > thanks
> >
> > I know about the sSliceArray.ucMode flag. However, it seems that siemens
> > is tricky with the order
> > of the slices. assuming the slices are numbered from 1 (foot) to n
> > (head), for an interleaved
> > acquisition it appears that the slice order is
> >
> > For an odd number of slices (N = odd)
> > 1:2:N, 2:2:N-1
> >
> > For an even number of slices (N = even)
> > 2:2:N, 1:2:N-1
> >
> > is this what others have? or is there a way to verify it?
> >
> > thanks
> > darren
> >
--
Dr. Roland Marcus Rutschmann <[log in to unmask]>
Institute for Experimental Psychology, University of Regensburg
Universitätsstraße 31, 93053 Regensburg, Germany
Tel: +49 941 943 2533, Fax: +49 941 943 3233
http://www.psychologie.uni-regensburg.de/Rutschmann
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