Gd shortens T2* fairly dramatically. So any sequence that is sensitive to
the T2* will show the presents of Gd and will be susceptible to changes in
its concentration.
These effects will generally be contained to the compartment to where Gd is
present e.g. vasculature. In fMRI experiment, Gd-contrast will increase the
"BOLD" contrast, however, since most of the Gd contrasts have short
elimination times and steep curve it is very hard to use, constructively.
So my advice would be to do fMRI before contrast injection.
pk
----- Original Message -----
From: "Markus Gschwind" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, April 23, 2008 9:24 AM
Subject: [FSL] EPI is it sensible to gadolinium?
> Hi!
>
> This is a question for the radiologist under the FSL people, sorry!
>
> Does anybody know if the contrast agent Gadolinium influences the images
> of a subsequent fMRI acquistion?
>
> Appearently there is no influence in DWI (Stroke. 2002;33:1799-1802), but
> on the other side there is Gado enhanced EPI imaging for all sort of
> tumors etc.
>
> We will scan patients with both structural (with contrast) and functional
> images and the best would be if we could do the functional part while
> waiting the 15 minutes for the post contrast T1 in order to safe time.
>
> Does anybody know?
>
> Very grateful!
> Markus
>
> --
>
> Dr. med. Markus Gschwind, M.D.
> Laboratory for Neurology and Imaging of Cognition
> Dept of Neurosciences
> University Medical Center (CMU)
> 1 Michel-Servet - 1211 GENEVA - CH
>
> Tel 0041 (0) 22 379 5324
> Fax 0041 (0) 22 379 5402
> email: [log in to unmask]
> http://labnic.unige.ch
>
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