> To convolve the grey matter images, are there any available softwares that
> have this function? Or are they using locally developed program?
SPM will convolve with a spatially invariant Gaussian kernel, but many people
who do partial volume correction actually convolve with the PSF from their scanner,
which may or may not be spatially invariant. SPM won't do this kind of convolution.
If you do additional smoothing of both the PET and MRI data (i.e. smooth
the PET with a FWHM of x mm, and the MRI with one of sqrt(x^2+y^2), where y
is the approximate FWHM of the PET PSF), then any mismatch between scanner
PSF and a simple Gaussian may be completely swamped by the extra smoothing.
Best regards,
-John
--
Dr John Ashburner.
Functional Imaging Lab., 12 Queen Square, London WC1N 3BG, UK.
tel: +44 (0)20 78337491 or +44 (0)20 78373611 x4381
fax: +44 (0)20 78131420 http://www.fil.ion.ucl.ac.uk/~john
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