I think that is not correct. As far as I understand, medx requires a volume
for the reference image.
I am starting from two slices that need coregistering in 2D. Then I want
that transformation applied to a volume (secondary image). Stefano
-----Original Message-----
From: talin [mailto:[log in to unmask]]
Sent: Thursday, January 17, 2002 10:40 AM
To: [log in to unmask]
Subject: Re: [FSL] 2 channel segmentation
The FSL registration routine in MEDx has been slightly modified so
that the user can specify a Group for Secondary Images while specifying a
Volume for the Input Image. .So you should be able to create a group of the
separate slices in the volume. Specify this group across secondary images.
This should allow all the slices to be corrected by the same transformation
matrix.
I hope this is of help
Talin
-----Original Message-----
From: Marenco, Stefano (NIMH) <[log in to unmask]>
To: [log in to unmask] <[log in to unmask]>
Date: Thursday, January 17, 2002 9:35 AM
Subject: Re: [FSL] 2 channel segmentation
>Thanks, that's a good suggestion.
>
>Here is another problem. I want to do a 2D registration on single slices.
No
>problem there. Then I want to use the resulting transformation matrix to
>correct the position of a volume in plane (i.e. I want to correct each
slice
>in the volume by the same parameters I used for the 2D registration). When
I
>used the GUI, only the first slice of the volume was corrected. Is there a
>way around this? Stefano
>
>-----Original Message-----
>From: Stephen Smith [mailto:[log in to unmask]]
>Sent: Wednesday, January 16, 2002 5:23 PM
>To: [log in to unmask]
>Subject: Re: [FSL] 2 channel segmentation
>
>
>Hi.
>
>On Wed, 16 Jan 2002, Marenco, Stefano (NIMH) wrote:
>
>> I do a segmentation from 2 channels (a proton density weighted and a t2
>> weighted image) and it works really nicely.
>> Then I take the input images and I register them to a third image. The
>> registration works fine.
>> I repeat the segmentation with the same parameters that I used initially
>and
>> I get a completely different result.
>> Can anyone explain this to me?
>
>I assume that the 2 channels are registered to each other before
>registration to the third image. Are you applying exactly the same
>transformation to both? If not, their registrations to the third may be
>subtly different, which may be causing this. Otherise, maybe it's
>intepolation effects which may be causing slight blurring. You could try
>using sinc interpolation in FLIRT instead....
>
>thanks :)
|