Hi Abby - You can try first reinitializing without increasing the number of control points, and if that doesn’t work then increase them. Increasing the number of control points increases the degrees of freedom in the shape of the path, which can be good, e.g., for the corpus callosum of subjects with enlarged ventricles, but otherwise may make things noisier.
Best,
a.y
From: <freesurfer-bounces@nmr.mgh.harvard.edumailto:freesurfer-bounces@nmr.mgh.harvard.edu> on behalf of Abigail Waters <awaters2@su.suffolk.edumailto:awaters2@su.suffolk.edu> Reply-To: Freesurfer support list <freesurfer@nmr.mgh.harvard.edumailto:freesurfer@nmr.mgh.harvard.edu> Date: Friday, August 25, 2017 at 1:32 PM To: "freesurfer@nmr.mgh.harvard.edumailto:freesurfer@nmr.mgh.harvard.edu" <freesurfer@nmr.mgh.harvard.edumailto:freesurfer@nmr.mgh.harvard.edu> Subject: [Freesurfer] Tracula - QA for Forceps Minor
Hello -
We've processed approximately 500 DTI scans using Tracula and are in the process of visually inspecting the forceps minor for errors.
For subjects with dramatic errors (see image 1) we will be redoing the -path step of Tracula with control points set to 7 and reinit = 1. Is this an appropriate solution? In order to generate the fminor_PP_avg33_mni_bbr_cpts_7 files, would we need to redo the whole pipeline, or just parts of it?
We would also like to know if any of the following issues described below are errors or normal variation in white matter tracts:
1. Spread of white matter at the ends of the curve (see image 2) 2. Overlapping of the white matter across hemispheres in the prefrontal region (see image 3) 3. Non-smooth surfaces with small protrusions along the length of the forceps minor (see image 4_1 and 4_2) 4. Slightly larger single protrusions of white matter (see image 5)
And if so, would increasing the number of control points to 7 increase the quality of the reconstruction?
Please let me know if you need any additional information. Best Abby