Influence of Prescan Normalization in Siemens scanners on PCASL acquisition

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Eric

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Aug 24, 2021, 11:54:36 PM8/24/21

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Dear Dr. Wang,

Thanks for your very useful toolbox, I have managed to adapt it for my first PCASL analysis.

I wonder if you could comment on whether turning 'Prescan normalize' on and off would (in)validate perfusion measures? I noticed that many of the available sequences (e.g., HCP-Aging) leave it off. The inhomogeneity of the image intensity from superficial to deep voxels is quite obvious, but I am not sure if the voxelwise scaling would 'destroy' any tagging of the perfusion signals.

Best regards,

Eric

Ze Wang

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Oct 19, 2021, 6:51:55 PM10/19/21

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Hi Eric,

I'm not sure what the "Prescan normalize" does. If it is a scan used to remove the image inhomogeneity, it should be applied to both M0 and ASL control and label images to avoid affecting perfusion signal.