> Congratulations for the new SPM5 version.
Thanks.
>
> I have dicom images recorded on a 3T GE Signa scanner and when I used the
> Dicom Import tool in SPM5, I got the following warning message:
>
> The AcquisitionNumber counter does not appear *
> * to be changing from one volume to another. *
> * Another possible explanation is that the same *
> * DICOM slices are used multiple times. *
> * The conversion is having to guess how slices *
> * should be arranged into volumes. *
> * 5 / 2 / 1
>
> Reading old spm messages I learned that this warning message might be
> because in the GE header files SeriesNumber and AcquisitionNumber are
> missing.
That's it.
>
> My question is how I can verify that the Dicom Import function has done
> correctly the conversion?
The best thing you can do is look at the images. There appears to be very
little information in the DICOM headers that tells you how the slices really
should be stuck together into volumes. Jesper originally had a fix for DTI
data from GE scanners, but I changed the code to make it a bit more general.
I hope it still works for DTI.
> How accurately is SPM5 guessing?
It should make a pretty good stab at getting it right. The changes to SPM
were based on a limited number of scans all from the same GE scanner, but the
conversion dealt with all the cases I gave to it.
>
> Also, I would like to know, If the order used by SPM5 to read files can
> affect this Dicom conversion function or not?
The order is based on the "Instance Number" tag in the DICOM headers, and not
on the order of file selection, so (providing you select all the files) the
order of selection shouldn't matter.
Best regards,
-John
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