Hi Pablo,
as far as I remember, Mark Jenkinson mentioned on the list that skew may have
rotation component.
Best,
Martin
On Tuesday 02 February 2010 02:41:54 Pablo Velasco wrote:
> Hi Martin,
>
> Thanks for the reference. However, I haven't been able to find in that
> paper any reference to eddy current producing image rotations. Am I
> missing something?
>
> Thanks again,
>
> -Pablo
>
> On Fri, 29 Jan 2010 18:21:31 +0100, Martin Kavec <[log in to unmask]>
wrote:
> >Hi Pablo,
> >
> >P. Jezzard, A. S. Barnett, C. Pierpaoli, Characterization of and
> > correction for eddy current artifacts in echo planar diffusion imaging.,
> > Magn Reson Med 39 (5) (1998) 801–812.
> >
> >cheers,
> >
> >Martin
> >
> >On Friday 29 January 2010 16:59:14 Pablo Velasco wrote:
> >> Hi Martin,
> >>
> >> Which P. Jezzard publication?
> >> Thanks,
> >>
> >> -Pablo
> >>
> >> On Thu, 28 Jan 2010 14:43:09 +0100, Martin Kavec
> >> <[log in to unmask]>
> >
> >wrote:
> >> >Hi Ed,
> >> >
> >> >you should be careful whether you want to use the b rotation or not.
> >> > The fact is that in simplified situation eddy-currents can cause the
> >> > image rotation as well (see publication of P. Jezzard). That is why
> >> > you can not be sure if the the source of rotation is eddy-currents or
> >> > the true subject motion. Rotation of the bvec in the former case would
> >> > not be a good idea and would bias your results.
> >> >
> >> >Best,
> >> >
> >> >Martin
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