Hi Ajna,
While I can't address your first question, I can affirm that using the phase and magnitude images from a 3.0 T Achieva can be used for unwarping in the Fieldmap toolbox as I've recently implemented that step on data from our own Achieva scanner. The one caveat is that the SPM Fieldmap toolbox requires that they are acquired with either AP or PA fold-over direction.
Kind regards,
Haakon Engen
University of Oslo
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Fra: Ajna <[log in to unmask]>
Sendt: 20. januar 2009 20:04
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Emne: [SPM] field map for spin echo epi
Dear SPMers,
I would like to use the SPM5 unwarping tool to correct any distortions
on my spin-echo EPIs acquired at 3T.
Few questions:
1.) Are field map generation tool and unwarping algorithm usable on
spin-echo epi data (as SPM had been developed primarily for use with
BOLD acquisition)?
2.) Our scanner (3T Philips Achieva) acquires magnitude and phase images
based on gradient-echo non-EPI sequence. Can I use these images for
making the field map to correct spin-echo epi data, or would I have to
acquire se-epi data at 2 TEs?
All hints and advice will be extremely appreciated.
-Ajna Borogovac, Columbia University
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