Hi,
It is always the dwell time (or effective echo spacing) of the EPI
sequence (DTI in this case) that is needed.
All the best,
Mark
On 5 Mar 2012, at 11:42, Jürgen Hänggi wrote:
> Hi Mark
>
> I have another question on that topic. In fugue, do I have to use the dwell
> time of the field map or do I need the dwell time of the to be corrected
> sequence, the DTI sequence?
>
> Thanks a lot
> Regards
> Jürgen
>
>
> On [DATE], "Mark Jenkinson" <[ADDRESS]> wrote:
>
>> Hi,
>>
>> Yes, in the FEAT GUI (the pre-processing section, which is what we
>> recommend you use, with the b=0 image as the "functional" input) we
>> need the "effective echo spacing" which is the actual echo spacing
>> (or dwell time) _divided_ by the acceleration factor (SENSE factor here).
>>
>> All the best,
>> Mark
>>
>>
>> On 5 Mar 2012, at 08:15, Jürgen Hänggi wrote:
>>
>>> Dear FSL experts
>>>
>>> We try to unwarp distortions in DTI data using field maps, but he DTI data
>>> were acquired with the SENSE technique (factor 2.0).
>>>
>>> Does the dwell time used in fugue have to be adjusted for the SENSE factor?
>>>
>>> If yes, do I have to multiply or rather divide the dwell time by the SENSE
>>> factor?
>>>
>>> Thanks in advance
>>> Best regards
>>> Jürgen Hänggi
>>>
>>>
>>> ----------------------------------------------------------------------------
>>> Jürgen Hänggi, Ph.D.
>>> Division Neuropsychology
>>> Institute of Psychology
>>> University of Zurich
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>
> ----------------------------------------------------------------------------
> Jürgen Hänggi, Ph.D.
> Division Neuropsychology
> Institute of Psychology
> University of Zurich
> Binzmuehlestrasse 14, PO Box 25
> 8050 Zurich, Switzerland
> 0041 44 635 73 97 (phone office)
> 0041 76 445 86 84 (phone mobile)
> 0041 44 635 74 09 (fax office)
> BIN 4.D.04 (office room number)
> j.haenggi[at]psychologie.uzh.ch (email)
> http://www.psychologie.uzh.ch/neuropsy/ (website)
> http://www.juergenhaenggi.ch (private website)
>
> This e-mail (and any attachment/s) contains confidential and/or privileged
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