Hi Roland
Check out my post in June:
http://www.jiscmail.ac.uk/cgi-bin/wa.exe?A2=ind0506&L=SPM&P=11562
We used a Siemens Trio but the sequence is the same I think.
Best regards,
Paul
On Thu, 1 Dec 2005 17:21:58 +0100, Roland Marcus Rutschmann
<[log in to unmask]> wrote:
>Hi,
>
>I tried using the fielemap toolbox for our Allegra Scanner. The gradient
>fielmap sequence produces 2 series with 3 volumes.
>
>2 Problems:
>
>1. In the first volume we have the absolute values for the 2 echo times, but
>the spm-dicom toolbox only produces the Analyze volume for the longer TE,
>which I think is the one I need. Am I correct here.
>
>Otherwise I have to apply some tricks as the header information is too
>similar. I'd have to seperate the slices first.
>
>2. The phase image is made up of unsigned intergers between 0 and 1950. From
>that I would suspect that scaling would go up to 2048. I can convert the pics
>to float but how is the mapping done?
>a) 0..2048 -> -pi..pi
>b) 0..2048 -> 0..2pi
>
>or am I completely off?
>
>Thanks for any help.
>
>Roland
>
>
>--
>Dr. Roland Marcus Rutschmann <[log in to unmask]>
>Institute for Experimental Psychology, University of Regensburg
>Universitätsstraße 31, 93053 Regensburg, Germany
>Tel: +49 941 943 2533, Fax: +49 941 943 3233
>http://www.psychologie.uni-regensburg.de/Rutschmann
>
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