Example usage - Freesurfer

Example usage - Freesurfer

Example usage - Freesurfer

A rough example of usage can be:

visualqc_freesurfer --fs_dir /project/freesurfer

which searches the specified directory for all subjects with successfully completed runs of Freesurfer and presents with cortical parcellation in all the three views, along with surface rendering (annotated with cortical ROIs). You can then review these visualizations for one subject at a time, rate their accuracy and move on to the next subject.

Note:
  • right click toggles the overlay as well as pressing key t
  • slider changes the opacity of the contour overlay in all slices
  • double click in a given slice zooms it full-window

You can choose to work on pre-selected list of subjects, as you choose:

visualqc_freesurfer --fs_dir /project/freesurfer --id_list list_complete.txt

Note the default visualization type is cortical_contour and you can change it to QC a particular ROI e.g. left hippocampus (label 17 in Freesurfer color lookup table (We can also use the shortcut vqcfs to invoke the same program. ):

vqcfs -f /project/freesurfer -i list_hippo.txt --vis_type labels_contour --labels 17

You can add as many ROIs as you wish

vqcfs -f /project/freesurfer -i list_hippo.txt --vis_type labels_contour --labels 10 11 12 13

However, be sure your layout is providing you with enough detail and convenience to get a quick glance of whole structure(s). If you don’t need all the 3 views, or you’d like to focus on one particular view that is ideal for a given ROI, you can specify that with –views. It accepts a list of dimensions (max 3), from 0 to 2, inclusive.

vqcfs -f /project/freesurfer -i list_hippo.txt --vis_type labels_contour -l 10 11 12 13 --views 0

If you would like many more slices or rows (or fewer), you can control that with –num_rows and –num_slices. These parameters are applied separately for each view (not the entire layout). So if you choose -r 3 and -s 10 for -w 0 2, then visualqc displays 10 slices in 3 rows for each of dimensions 0 and 2 (20 panels in total).

vqcfs -f /project/freesurfer -i list_hippo.txt --vis_type labels_contour -l 10 11 12 13 --views 0 -w 0 2 -r 3 -s 10

Generating and Downloading Required Files from a remote SSH server

This process consists of few steps:

  • ssh to the remote server, and cd into the Freesurfer subjects directory
  • tar the required files (see below), to retain the folder structure
  • download it to your local computer,
  • untar it while retain the nested folder structure

Sample commands to achieve the above are shown below - please use the appropriate values for the various capitalized/highlighted variables:

cd $FS_SUBJECTS_DIR
tar -cjvf tar_visualqc_files.tar */mri/{orig,aparc+aseg}.mgz
<<logout of ssh>>
scp USERNAME@REMOTE.SERVER:$FS_SUBJECTS_DIR/tar_visualqc_files.tar <<LOCAL_FS_DIR>>
cd <<LOCAL_FS_DIR>>
tar -xjvf tar_visualqc_files.tar

As with other modules of VisualQC, you can choose which views, how many slices and rows to display using the Layout command line arguments i.e. --views, --num_slices and --num_rows.