That is very strange, it is common to get good registrations with even
nonlinear registration with FA to T1. Are you brain extracting your images?
Peace,
Matt.
-----Original Message-----
From: FSL - FMRIB's Software Library [mailto:[log in to unmask]] On Behalf
Of Adil Javed
Sent: Friday, March 12, 2010 1:25 AM
To: [log in to unmask]
Subject: Re: [FSL] DTI imaging
Hi Matt,
Thanks for your comments, very educational and helpful. When I transform FA
to T1 or T2, the only Model/DOF that works is Translation (3 parameters
model). The others, including rigid body (6 parameters) or more (7-9) give
me very distorted images. Is registration by translation only (3
parameters) good enough?
many thanks,
aj
--- On Wed, 3/10/10, Matt Glasser <[log in to unmask]> wrote:
> From: Matt Glasser <[log in to unmask]>
> Subject: Re: [FSL] DTI imaging
> To: [log in to unmask]
> Date: Wednesday, March 10, 2010, 8:51 PM
> That is not the right way to go about
> things. You should leave the voxel
> dimensions at 2x2x2mm and then Register the FA to the T1 to
> get the desired
> overlay. It is MUCH better to interpolate the
> calculated data than to
> interpolate the raw data and then calculate. This is
> especially true if you
> want to do tractography. You can easily still specify
> masks in structural
> space and then specify the structural to diffusion
> transform.
>
> Peace,
>
> Matt.
>
> -----Original Message-----
> From: FSL - FMRIB's Software Library [mailto:[log in to unmask]]
> On Behalf
> Of Adil Javed
> Sent: Wednesday, March 10, 2010 6:20 PM
> To: [log in to unmask]
> Subject: [FSL] DTI imaging
>
> Hi,
> for those who are experts in DTI:
> I am acquiring DTI images on 3.0T Phillips scanner using 32
> directions, FOV
> 240, acquired matrix is 120 x 118 with acquired voxel
> dimensions of 2x2x2.
> In order to overlay DTI FA/MD/ or tracts on a FLAIR or T1
> image, I need to
> reconstruct the matrix to 256 with voxel RECON to 0.94 x
> 0.94 x 2 so they
> align with my FLAIR or T1 images.
>
> Question: is this ok or do you see any problems with
> this approach? By
> reconstructing voxels down to 0.94 x 0.94 x 2 after they
> are Acquired in
> 2x2x2 size, am I losing any information?
>
> many thanks for your help.
>
> adil
>
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