Thank you.
Unfortunately, we use a Phillips scanner for 3T scans: MPRAGE T1 TR 9.89; TE 4.60. If you have any suggestions, including which of the protocols comes closest, let mw know. Best, Octavian
On 1/31/12, Andre van der Kouwe andre@nmr.mgh.harvard.edu wrote:
Do you have a Siemens scanner?
You can compare your protocols with the examples at www.nmr.mgh.harvard.edu/~andre.
On Tue, 31 Jan 2012, Bruce Fischl wrote:
Hi Octavian
what kind of scanner are you using? Andre van der Kouwe and Dylan Tisdall (ccd) have developed a multi-echo mprage that allows one to identify dura by it's short T2*. They might be able to give it to you depending on your scanner and relationship with Siemens. Otherwise it can be difficult, as lenghtening your TE to reduce the dura signal also reduced gray/white contrast.
cheers Bruce On Tue, 31 Jan 2012, octavian lie wrote:
Dear All,
I am trying to perform brain extraction on T1 3D images, however the dura appears too bright and thick compared to the underlying gray matter. It seems that I have a hard time stripping the dura away. Do you have any suggestions in terms of optimizing freesurfer parameters to help with this problem, or alternatively, do you suggest a specific T1 protocol (TE/TR) to dim the dura a bit? Thank you,
Octavian Lie. _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
The information in this e-mail is intended only for the person to whom it is addressed. If you believe this e-mail was sent to you in error and the e-mail contains patient information, please contact the Partners Compliance HelpLine at http://www.partners.org/complianceline . If the e-mail was sent to you in error but does not contain patient information, please contact the sender and properly dispose of the e-mail.
the alternative is to collect a T2-space (does that exist on Phillips?). I'm putting together some tools to use the T2 to correct the pial surface placement in the presence of dura On Tue, 31 Jan 2012, octavian lie wrote:
Thank you.
Unfortunately, we use a Phillips scanner for 3T scans: MPRAGE T1 TR 9.89; TE 4.60. If you have any suggestions, including which of the protocols comes closest, let mw know. Best, Octavian
On 1/31/12, Andre van der Kouwe andre@nmr.mgh.harvard.edu wrote:
Do you have a Siemens scanner?
You can compare your protocols with the examples at www.nmr.mgh.harvard.edu/~andre.
On Tue, 31 Jan 2012, Bruce Fischl wrote:
Hi Octavian
what kind of scanner are you using? Andre van der Kouwe and Dylan Tisdall (ccd) have developed a multi-echo mprage that allows one to identify dura by it's short T2*. They might be able to give it to you depending on your scanner and relationship with Siemens. Otherwise it can be difficult, as lenghtening your TE to reduce the dura signal also reduced gray/white contrast.
cheers Bruce On Tue, 31 Jan 2012, octavian lie wrote:
Dear All,
I am trying to perform brain extraction on T1 3D images, however the dura appears too bright and thick compared to the underlying gray matter. It seems that I have a hard time stripping the dura away. Do you have any suggestions in terms of optimizing freesurfer parameters to help with this problem, or alternatively, do you suggest a specific T1 protocol (TE/TR) to dim the dura a bit? Thank you,
Octavian Lie. _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
The information in this e-mail is intended only for the person to whom it is addressed. If you believe this e-mail was sent to you in error and the e-mail contains patient information, please contact the Partners Compliance HelpLine at http://www.partners.org/complianceline . If the e-mail was sent to you in error but does not contain patient information, please contact the sender and properly dispose of the e-mail.
It may be called "VISTA" on Philips. Here under "Structural T1 Parameters" are Philips equivalents to our MPRAGE but they don't include the multiecho trick to reduce chemical shift of dura and use T2* to distinguish dura from adjacent white matter:
http://intrust.spl.harvard.edu/pages/Imaging
On Tue, 31 Jan 2012, Bruce Fischl wrote:
the alternative is to collect a T2-space (does that exist on Phillips?). I'm putting together some tools to use the T2 to correct the pial surface placement in the presence of dura On Tue, 31 Jan 2012, octavian lie wrote:
Thank you.
Unfortunately, we use a Phillips scanner for 3T scans: MPRAGE T1 TR 9.89; TE 4.60. If you have any suggestions, including which of the protocols comes closest, let mw know. Best, Octavian
On 1/31/12, Andre van der Kouwe andre@nmr.mgh.harvard.edu wrote:
Do you have a Siemens scanner?
You can compare your protocols with the examples at www.nmr.mgh.harvard.edu/~andre.
On Tue, 31 Jan 2012, Bruce Fischl wrote:
Hi Octavian
what kind of scanner are you using? Andre van der Kouwe and Dylan Tisdall (ccd) have developed a multi-echo mprage that allows one to identify dura by it's short T2*. They might be able to give it to you depending on your scanner and relationship with Siemens. Otherwise it can be difficult, as lenghtening your TE to reduce the dura signal also reduced gray/white contrast.
cheers Bruce On Tue, 31 Jan 2012, octavian lie wrote:
Dear All,
I am trying to perform brain extraction on T1 3D images, however the dura appears too bright and thick compared to the underlying gray matter. It seems that I have a hard time stripping the dura away. Do you have any suggestions in terms of optimizing freesurfer parameters to help with this problem, or alternatively, do you suggest a specific T1 protocol (TE/TR) to dim the dura a bit? Thank you,
Octavian Lie. _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
The information in this e-mail is intended only for the person to whom it is addressed. If you believe this e-mail was sent to you in error and the e-mail contains patient information, please contact the Partners Compliance HelpLine at http://www.partners.org/complianceline . If the e-mail was sent to you in error but does not contain patient information, please contact the sender and properly dispose of the e-mail.
freesurfer@nmr.mgh.harvard.edu
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Andre van der Kouwe -
Bruce Fischl -
octavian lie