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Dear Dr Demirkaya,

I fear that there may not be anyone in the department who is any keener to
try to answer this question than I am.  It is well outside the normal range
of things that are discussed here, and one would need to be a cardiac
physiologist to understand the problems that need to be overcome.  We don't
have any of those in the Wellcome Department of Cognitive Neurology.

I am not sure that it is possible to give a simple answer without knowing a
bit more about what you intend.  Clearly a heart that is alive will be
moving, and if you are intending to measure the PET signal under different
pharmacological conditions in one individual, then the excursion of the
movement may vary between conditions.  Not only will the PET image be
extremely blurred, but any differences between different conditions may be
completely swamped out by movement artifact.  Realignment, since it is a
rigid-body transformation, won't be able to accommodate changes in shape of
the heart, and presumably wouldn't have many anatomical landmarks to work
on.

If you intend to do some kind of group analysis, then you would need to be
able to 'normalize' your images.  Normalization to a template won't really
be possible as the myocardial wall in a normal heart (which you would
presumably use as your template) will give a fairly uniform signal, I would
imagine.

Anyway, these are technical issues which aren't specific to SPM, and which
we aren't really in a position to comment upon.  However, if there was some
way of deriving a PET signal which is specific to a particular piece of
myocardial tissue, and this is different in different conditions, then one
could in theory imagine that the set of images could be analyzed using the
general linear model, in the way that is done within the 'statistics' part
of SPM,

Sorry not to be able to be of more help,

Richard Perry.

>Hi
>
>I recently ran accross SPM and am new in your list. I liked SPM for the fact
>that it is written
>in Matlab which is a platform I am very familiar with. At the moment,  I am
>trying to understand
>what SPM can/can not do. My first general, rather simple, question is:
>
>Can it be used to process/analyze PET images of the heart?
>
>Omer Demirkaya, Ph.D.
>Biomed. Stats. & Scientific Computing
>KFSH&RC
>MBC #03 PO Box 3354
>Riyadh, 11211 KSA
>Phone/VoiceMail: 966-1-464-7272 ext:32504
>Fax: 966-1-442-7854
>email: [log in to unmask]
>
>
>
>Attachment converted: Ravel:FileItem.txt (TEXT/MSIE) (0003CFD0)


from: Dr Richard Perry,
Clinical Research Fellow, Wellcome Department of Cognitive Neurology,
Darwin Building, University College London, Gower Street, London WC1E 6BT.
Tel: 0171 504 2187;  e mail: [log in to unmask]
Pager: 04325 253 566.




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