Dear Erik,
PET is a wide field. Do you use H2[15O]? In that case you need to
somehow be able to tell SPM that you have 26 images from the same
subject for realignment; this will work with the 26 different Analyze
images.
A similar strategy would apply if you were talking about 26 time frames
of a dynamic ligand study - again, you need to be able to differentiate
them. Note that for radioligands that have a spatially very divergent
pattern over time (e.g. "basal ganglia" ligands, raclopride and the
like) it may be difficult to check the accuracy of realignment, or
indeed whether the strategy is beneficial - try decay-corrected
time-activity curves on high contrast regions before and after
realignment.
I don't know whether SPM is capable of deciphering a 4D NIFTI header for
realignment purposes - it might be.
Good luck,
HTH, A
-----Original Message-----
From: SPM (Statistical Parametric Mapping) [mailto:[log in to unmask]]
On Behalf Of Erik Jaeger
Sent: 21 March 2007 22:49
To: [log in to unmask]
Subject: [SPM] PET realignment
I am new to SPM and I would like to run a PET analysis with the
software.
The dynamic PET images were originally in ECAT7 format. When I converted
the
files to analyze, 26 images and headers were produced, one for each
frame.
When converted to NIFTI, however, only one file resulted. Which format
should I use for my analysis, particularly at the realignment step?
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