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You could do that but because white is the counting surface and pial is the stopping surface it is unlikely to be necessary.
So basically you don’t like the fact that when a surface triangle is hit, all three vertices counts are incremented instead of the nearest vertex? I suppose that’s not such a good idea if one were connection strengths of different kinds of structures.
I’ll ask them about it this afternoon.
Peace,
Matt.
From: basile pinsard <[email protected]>
Date: Thursday, June 5, 2014 at 11:42 AM To: Matt Glasser <[email protected]> Cc: Donna Dierker <[email protected]>, "[email protected]" <[email protected]> Subject: Re: [HCP-Users] gifti labels to volume ok, do you have applied dilation to the mask before inverting it? can't there be side effect between aliased volume mask and wm/gm surfaces?
However I wonder if in the case it misses the surface for stopping condition and crosses over if the fiber is counted as endpoint in the matrix... the second point is about normalization of the matrix when summing over regions of interest (to get some kind of more quantitative value). When a fiber hits a triangle all of the 3 vertex entries in the matrices (let say rows) to the other endpoint of
the fiber have their count increased of 1. so it will count each fiber either 4*3/2= 6 times if one end is on a vertex and the other in a volume ROI or 6*5/2=15 times if both endpoints are surfaces. So dividing by this numbers the fibers count when summing
over ROIS is necessary to get sensible results. However the diagonal value will carry over-estimated self-connecting fibers as pairs of vertices in the same triangle have their count increment each time a fiber hits this triangle. This can be filtered if you
remove every matrix entry of neighboring vertices on the surface.
hope this is clear enough, you can also see this thread here:
https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=fsl;a98283e4.1405
cheers
basile On Thu, Jun 5, 2014 at 12:26 PM, Glasser, Matthew
<[email protected]> wrote:
-- Basile Pinsard
PhD candidateUnité de Neuroimagerie Fonctionnelle, CRIUGM, Université de Montréal The materials in this message are private and may contain Protected Healthcare Information or other information of a sensitive nature. If you are not the intended recipient, be advised that any unauthorized use, disclosure, copying or the taking of any action in reliance on the contents of this information is strictly prohibited. If you have received this email in error, please immediately notify the sender via telephone or return mail. _______________________________________________ |
- [HCP-Users] gifti labels to volume basile pinsard
- Re: [HCP-Users] gifti labels to volume Timothy Coalson
- Re: [HCP-Users] gifti labels to volume Donna Dierker
- Re: [HCP-Users] gifti labels to volume basile pinsard
- Re: [HCP-Users] gifti labels to volume Glasser, Matthew
- Re: [HCP-Users] gifti labels to vol... basile pinsard
- Re: [HCP-Users] gifti labels to... Glasser, Matthew
- Re: [HCP-Users] gifti label... basile pinsard
- Re: [HCP-Users] gifti label... Glasser, Matthew
- Re: [HCP-Users] gifti label... Saad Jbabdi
- Re: [HCP-Users] gifti label... basile pinsard
