Hi,
I'm not sure if this is the answer, but abstract 101 from Kyoto
talks about Maxwell terms affecting the signal when the twice
refocused sequence is used with an asymmetric gradient coil.
With a half Fourier acquisition, the Maxwell terms can shift
k-space away from the sampled region and I suppose this gives
a signal that is too low and hence looks like high diffusion?
Regards,
David Atkinson
Mark E. Bastin wrote:
> Hi Folks,
> This is a question for those of you who have a GE Signa.
> We are currently assessing the dual spin-echo acquisition on our
> system (9.1M4), which is supposed to reduce eddy current artefacts,
> but find that the <D> values are radically inaccurate compared with
> results from our standard acquisition. I seem to remember reading
> something about this on the EPIC users group e-mail list, but cannot
> recall what the answer was. Do any of you use this option, and if
> so what have been your experiences?
>
> Of course it could just be that there is a bug in GE's software that
> means it doesn't work as it should. It's happened before ...
>
> Cheers,
>
> Mark
>
> Dr. Mark E. Bastin
> Medical and Radiological Sciences (Medical Physics)
> University of Edinburgh
> Western General Hospital
> Crewe Road
> Edinburgh, EH4 2XU
> UK.
>
> TEL: ++44 (0)131 537 2511
> FAX: ++44 (0)131 537 1026
--
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David Atkinson [log in to unmask]
Imaging Sciences, KCL, Guy's Hospital, London, SE1 9RT.
** New numbers ** Tel 020 7188 5444, Fax 020 7188 5442.
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