Hi,
interesting - I have seen it once on our recently installed 3T TIM Trio with a 3 diffusion dir EPI. Did not know what to make out of it either and have no explanation. Actually, it was even worse and extended to frontal parts as well. Notably, I was not able to reproduce it so far (another patient scanned immediately after was just fine). Probably worth to go into it. i.e. show it to Siemens. Keep me posted.
Cheers, Andreas
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Von: FSL - FMRIB's Software Library im Auftrag von Markus Gschwind
Gesendet: Di 20.11.2007 18:11
An: [log in to unmask]
Betreff: [FSL] DTI: Vibration Artefacts in Siemens 3T
Hello !
Does anyone have experience with the "Siemens Magnetom Trio" 3T MRI
and its behavior in
DTI sequences?
We suffer from a poor-signal-artifact in the mid-parietal area that:
- occurs only in the directions of x far from 0 (x=0.75 to 1 and
x=-0.75 to -1)
in our 30direction sequence this is always the directions 6, 14, 15
22, 28,29,30
- occurs in an uncontrollable manner in 75%, dependent on subject,
TR/TE and head
fixation.
That means we havn't found one single reason.
See attached example, please
Help! Does anyone know that sort of artifact in a Siemens Magnetom Trio?
Does anyone know why it is allways and only the x-gradient?
Does anyone know what to do against?
Thanks a lot in advance!
Markus
--
Dr. med. Markus Gschwind, M.D.
Laboratory for Neurology and Imaging of Cognition
Dept of Neurosciences
University Medical Center (CMU)
1 Michel-Servet - 1211 GENEVA - CH
Tel 0041 (0) 22 379 5324
Fax 0041 (0) 22 379 5402
email: [log in to unmask]
http://labnic.unige.ch <http://labnic.unige.ch/>
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