Hi SPM-ers,
Again, more questions about SPM from me.
These are my questions (to ease up my confusness) and perhaps I've already
asked these questions:
• according to SPM-VBM, it said that before doing a VBM analysis ,
the images should be checked its alignment by choosing T1.nii. How about
T2 and FLAIR images? Since in SEGMENT if we choose the Tissue Probablity
Maps option it always refer to GM-WM-CSF.nii of T1 images.
• in the paper " Unified Segmentation ". It mentioned about
eavaluations with BrainWeb phantoms for images of T1, T2 and PD. Also
mentioned about Dice metric which measured or compares images with "true"
grey and white matter. Do you familiar with those? If yes, regarding the
T2 and PD images, which files should I specified in the Tissue probability
Maps.
• Bias correction. Could you explain me more in "a simple way" on
its concept (also Bias regulation and Bias FWHM)? In the paper, it said
that it should be handled properly. So far what I did in my study I always
choose SAVE bias corrected. Would it be influenced my volume calculation?
As far as I understand it has relation with the inhomogenity of the
images. Am I right?
Thank you.
kind regards,
Dini
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