Dear Wei Wen and Martin,
>
> Let's ask Mark Jenkinson about that, probably he knows about that.
I'm afraid that I don't know anything about running GE scanners.
This sort of hardware/acquistion specific question is really beyond the
scope of what we do - all I can do is reiterate that I suggest you acquire
two spin-echo images, one with the echo time offset from the symmetric
centre position.
How you get the sequence up and running on your system is something
you'll have to work out yourselves, or hope that some kind soul on the
list also has a GE scanner and can help you with this acquisition.
All the best,
Mark
Wei Wen wrote:
>
> Dear Martin,
>
> Sorry. No idea. In my case, I requested it to the MRI centre that we scan
> our subjects and they asked for advice from GE maintenance engineer. Sorry
> about that. Normally, on this list, people normally provide
> suggestions/comments to questions, but I am not able to in this case. I am
> still waiting for the file from the MRI centre and maybe I will be asking
> questions again when using it.
>
> Let's ask Mark Jenkinson about that, probably he knows about that.
>
> Regards,
>
> Wei Wen
> ----- Original Message -----
> From: "Martin Kavec" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Friday, March 01, 2002 7:31 PM
> Subject: Re: [FSL] EPI distortion correction
>
> > Dear Wei Wen,
> >
> > On Thursday 28 February 2002 06:34, you wrote:
> > > Dear Mark,
> > >
> > > 1. When we are getting the fieldmap, do we use exactly the same
> parameters
> > > as we did with the previous EPI acquisition?
> > >
> > > 2. You used 2.5ms offset on your 3T scanner. Ours is a 1.5 T GE scanner.
> > > Should we use the same offset or else please?
> >
> > Since I am also interested in fieldmap correction using FSL and
> work on GE
> > scanner as well, I would like to ask you for some initial hints.
> > How do you acquire symmetric and asymmetric echoes? Did you have
> to modify a
> > Spin echo sequence code or is there an easier way?
> > I appreciate any help.
> >
> > Regards,
> >
> > Martin
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