Hello,
I need some help regarding the analysis of resting state ASL data. We are testing the effects of several drinks in regional blood flow, so we acquire resting state perfusion data twice within a day, pre-drink and post-drink.
My first question is what is the best way to analyse the resting state ASL data. I have used the full perfusion model described on the website, from which I have removed the two BOLD-related EVs and the corresponding contrasts, so I am left with the first (c-t) column only. To check for differences, I ran a paired-samples t-test comparing the pre- and post- drink data, similar to what I'd do for BOLD data. Does this sound like the correct way of doing that? I got several blobs, hopefully reflecting differences in regional CBF, and I need to calculate the CBF value in these ROIs.
Has anyone attempted something similar? I have tried the SPM-compatible ASLtoolbox, but the ROI drawing tool does not permit me to select ROIs larger than a single voxel. I have also tried creating my ROIs via fslroi from both the asl and the M0 files, and they seem to be working OK with the ASLtoolbox. Do people agree with this method?
Thanks! Any help woud be appreciated!
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