[Camino-users] question re interpolated tractography

[Michael Zeineh]

Hi all,

A question re interpolation on with tractography and curvature thresholds. Let us say voxel size is 2mm isotropic.

If interpolation is OFF, then the I assume the curvature is measured voxel to voxel along the course of the track, and if the curvature from one voxel to the next (separated by the step size of 2mm) exceeds the threshold, then the track is stopped.

If interpolation is ON (and the step size is the default of 0.2mm), then the same things happens, but across a much shorter distance (which means that the track is much less likely to curve anyways).

So a net effect of this is that for the same track, one obtained with interpolation on, and the other with interpolation off, the measured curvature will be different? So one should have a more strict threshold with interpolation on?

Or is my thought process totally off, and curvature is measured independently from the step size in some way ...

Thank you for any comments,

Michael Zeineh, M.D.-Ph.D.
Assistant Professor, Dept of Radiology
300 Pasteur Drive, Room S-047
Stanford, CA  94305-5105
t:  650-721-1419
c: 650-722-2235
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mzeineh at stanford.edu