[Mristudio-users] Sagital DTI

[Susumu Mori]

I wonder if it is simply visualization issue.
Please make sure to choose "sagittal" for visualization, when you load the
data.
Because now your image Z is anatomical RL, your RL fiber should look blue,
which is different from the conventional DTI presentation, but it is just a
cosmetic issue.


On Fri, Nov 8, 2013 at 12:19 PM, Vadim Malis <vadmalis at mail.com> wrote:

> We are acquiring a DTI sagital slice of the lower leg on a 1.5 T GE
> scanner (feet first, supine).  When we look at the bvec values in the DICOM
> header, they are correctly (re) oriented.  This is by comparison to an
> axial DTI scan (our regular orientation for DTI).  We also confirmed from
> the mristudio-users group that indeed GE scanners give the correct bvec
> orientation that tracks slice orientation.  However, when we extract the
> eigenvectors for the sagittal slice using the bvecs from the DICOM headers,
> the lead eigenvector shows the X axis (LR) and the Z axis (SI) switched.
> Where we expect fiber eigenvectors to point SI, they are in LR.  When we
> switched gradient values in the bvec file (X-->Z and Z--> X) we did get the
> DTI lead eigenvector to be in the correct direction, but when fiber
> tracking it appears somehow the tracking switches X and Z again.  We would
> really appreciate if an expert could tell us what we are doing wrong.
>
>
> ------------------------------------------------------------------------------------------------------------------------------
> Vadim Malis
>
> _______________________________________________
> mristudio-users mailing list
> mristudio-users at mristudio.org
> http://lists.mristudio.org/mailman/listinfo/
> Unsubscribe, send a blank email to:
> mristudio-users-unsubscribe at mristudio.org
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.mristudio.org/pipermail/mristudio-users/attachments/20131117/0666299c/attachment.html