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mid-sagittal plane

Posted: Tue Sep 27, 2005 1:33 pm
by sjbabdi
hi !

I am wondering if some Aims routine gives the mid-sagittal plane (I guess this plane is computed, at least for the hemispheres separation).
In addition, is the algorithm used to compute this plane robust to the presence of hemisphere disymmetries (like tumors...).



Posted: Tue Sep 27, 2005 7:52 pm
by Jean-Francois Mangin
unfortunately, we never took time to reimplement one of the variants detecting this plane proposed in literature. It would be very useful at least to add various checking in the process. In fact, in the pipeline, the interhemispheric plane stems from the coordinates of AC, PC and a third point either given at the beginning manually, or deduced from the normalization.

You should note, however, that because of large assymetries (torque, petalia...), or pathology, the interhemispheric plane is not always a perfect plane. This is the reason why our pipeline stick to mathematical morphology to split the brain in hemispheres... The knowledge of its location mentioned above is used for a registration with a template defining the morphological seeds.

Mid sagittal plane computation

Posted: Tue Oct 18, 2005 10:53 am
by delzescaux
Hi, you can try this command to estimate the mid-sagittal plane

AimsMidPlaneAlign = Rectify the image and compute the rectified transformation (register the original image and its symetric and applies half of the estimated transformation which provides a superposition of the interhemispheric plane with the plane x=dimX/2 in the computed image)

We tested this algorithm with symetric volumes, hemisphere disymmetries should be tested.

Posted: Sat Oct 29, 2005 3:14 pm
by Jean-Francois Mangin
I would like to test this massively with you one of these days, and discuss about adding robustness if required for pathologic cases...

Re: mid-sagittal plane

Posted: Mon Nov 03, 2008 8:42 am
by joly
Dear all,
AimsMidPlaneAlign is not in the last distribution (3.1) , right ?
Is it possible to use another Aims/Vip whatever command to do a similar job ?
Do you think I can try to register (MIRegister) a volume with its left/right flip version ?
I will try, except if you suggest me another way :)

Re: mid-sagittal plane

Posted: Wed Nov 05, 2008 12:13 am
by riviere

Right, AimsMidPlaneAlign is not in the 3.1 distribution. I had never really noticed it... Well, this command has been moved to a new toolbox (for biological processing) that has not been publicly released yet. Not that it is specialized for biological applications, but the team who has developped it has taken it back in their toolbox to get the maintenance on it.
But fortunately this toolbox ("BrainRAT") is now almost ready and will be released within a couple of weeks in BrainVisa 3.1.4, so you will find AimsMidPlaneAlign back (together with a set of other commands).