Please cc the list, so that others can respond and benefit from the exchange.
No, we don't have an issue with TR/TE changing between our structural scans on Siemens scanners. Is there perhaps a mode of operation of a GE scanner that overrides that sort of behavior, so that it keeps TR/TE completely constant? If you're operating
the scanner in a regime where RF deposition is near its limit, you might have to intentionally "back off" to derive a set of parameters that will basically work for all subjects.
cheers,
-MH
--
Michael Harms, Ph.D.
-----------------------------------------------------------
Conte Center for the Neuroscience of Mental Disorders
Washington University School of Medicine
Department of Psychiatry, Box 8134
660 South Euclid Ave.
Tel: 314-747-6173
St. Louis, MO 63110
Email: mha...@wustl.edu
From: Rachel Woodall <rachel.wood...@york.ac.uk>
Date: Thursday, November 26, 2015 6:00 AM To: "Harms, Michael" <mha...@wustl.edu> Subject: Re: [HCP-Users] MRI parameters Hi Michael,
Apologies, I probably did not make myself very clear.
I set up my scan protocol, assuming that the parameters I used would be fixed and the same for every scan. However, upon checking the DICOM information after the scan, the TR and TE have
differed from what was input.
I have asked my radiographer whether this would be expected and he said that the differences between the two sets of parameters are trivial and I do not believe (in the absence of the parameters)
that you would be able to distinguish one from the other. All GE systems will modify certain parameters based on a patients weight (especially FSE T2 waited scans where RF deposition is high) and as a consequence the effective TE will vary by a few milliseconds.
The nature of my project requires a follow up of the same participants so I am now concerned that the follow up scan will not match the original and what effect this has on the data.
Therefore, I wanted to contact someone within the HCP to see if this is also something you have experienced when the image parameters have been checked post-scan.
Thanks again for your help.
Kind regards,
Rachel
On 19 November 2015 at 14:39, Harms, Michael
<mha...@wustl.edu> wrote:
-- Rachel Woodall
Research AssociateDepartment of Psychology
YO10 5DD
Email:
rachel.wood...@york.ac.ukThe materials in this message are private and may contain Protected Healthcare Information or other information of a sensitive nature. If you are not the intended recipient, be advised that any unauthorized use, disclosure, copying or the taking of any action in reliance on the contents of this information is strictly prohibited. If you have received this email in error, please immediately notify the sender via telephone or return mail. _______________________________________________ |
- [HCP-Users] MRI parameters Rachel Woodall
- Re: [HCP-Users] MRI parameters Harms, Michael
- Re: [HCP-Users] MRI parameters Harms, Michael
- Re: [HCP-Users] MRI parameters Gaurav Patel
- Re: [HCP-Users] MRI parameters Barbara Kreilkamp
- Re: [HCP-Users] MRI parameters Glasser, Matthew