We have a Philips 3T and some experience with generating B0 maps. Do you have a clinical science key. What version of the software are you using -- we are at 2.6.3 SP4
If you would like to contact us off line ([log in to unmask]) we will be happy to help.
Clark
-----Original Message-----
From: FSL - FMRIB's Software Library [mailto:[log in to unmask]] On Behalf Of Matt Glasser
Sent: Wednesday, September 29, 2010 11:35 AM
To: [log in to unmask]
Subject: Re: [FSL] field map for Philips 3T
Phillips should just have a standard field map sequence (I know Siemens
does). This should have already optimized parameters. Not having access to
Phillips scanners, I'm not able to help much more. I have some Philips
field map data given to me that has TEs of 20 and 24 ms.
Peace,
Matt.
-----Original Message-----
From: FSL - FMRIB's Software Library [mailto:[log in to unmask]] On Behalf
Of Jenifer Juranek
Sent: Tuesday, September 28, 2010 6:26 PM
To: [log in to unmask]
Subject: Re: [FSL] field map for Philips 3T
Thanks so much for your responses Matt and Mark.
I've loaded the "fieldmap" DICOM folder into a dicom viewer (the one Matt
suggested) and see there are 3840 images (that is a *lot* more that I
originally expected when I asked for a fieldmap). According to the dicom
tags, 32 different echoes were used (ranging from 1.994 - 39.49ms with a TR
of 50ms). The sequence is 3D SPGR with a flip of 60 and NEX=2.
Aside from the pixdim=1/1/2 (which should have been 2/2/2) what adjustments
should be communicated to them? Matt already confirmed that NEX=2 is
probably not necessary. Are 32 echoes a bit much? Do I only need 2? How far
apart should the echo times be?
Thanks again for any advice you can provide. I guess that Rorden's dcm2nii
converter is not prepared to handle this dataset. When FSL's slices errored
out, I knew that this data was not a "typical" fieldmap. Any suggestions to
communicate what a typical fieldmap should be are greatly appreciated.
Jenifer
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