Dear Nathan,
> I'm using SPM99 for PET analyses. My raw PET scans are VERY
> different from each other in terms of their translations and
> rotations. I've used the DISPLAY option in SPM to manually
> translate and rotate each image so that their origins fit in the
> AC/PC plane. I've also used the Check Reg option to verify that
> each image matches each other adequately. However, when
> realigning the images the translations are huge (20-30 mm)
> because their individual origin locations (ex. [128 128 11] and
> [140 160 8]) differ largely. I can't seem to get around this
> and I know that one should not proceed further if translations
> exceed ~5mm.
>
> Any suggestions?
I'd suggest that you check the results of your coregistration visually.
If they match, and if they match again after that when you open them
separately in a display window, the proper .mat file was has been
written.
When you manually adjusted the origins of the PET-scans - did you make
sure to rewrite the header/.mat file? And was that .mat file used as
input for the coregistration process?
Good luck,
Alle Meije
--
Alle Meije Wink
Institute for Mathematics and Computing Science, room 105
University of Groningen P.O. Box 800
9700 AV Groningen
Telephone +31 50 363 71 27 The Netherlands
Fax: +31 20 875 48 00
E-mail: [log in to unmask]
WWW: http://www.cs.rug.nl/~wink
" I guess it comes down to a simple choice, really.
Get busy living, or get busy dying. "
(Andy Dufresne in The Shawshank Redemption)
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