Modes of Statistics Calculation

The following statistics modes are supported:

• Statistics: Apply the VOIs to the selected image and show the resulting statistics on a panel.
• Multi-Statistics: Apply the VOIs to all loaded images and show the resulting statistics on one panel per image. The outcome can then easily be merged into an aggregate.
• File-Statistics: Apply the VOIs to a set of image files and save the resulting statistics in a file. This procedure requires explicit image loading and is most useful when the images are in a normal (e.g. MNI) space, so that a standard set of VOIs can be applied.
• Pixel Dump: Extract the values in all VOI pixels of the selected image and save the values together with the pixel coordinates in a file. This procedure gives the user the full raw data and allows him implementing his own statistical analysis.
• File-PixelDump: Extract the values in all VOI pixels from a set of image files and save the values together with the pixel coordinates in a file.

VOIs used for Statistics

The following VOIs are considered in the interactive statistics calculation:

• All contour VOIs on the List tab.
• The VOI named Group which consists of all the contour VOIs which are selected on the Group tab.
• If on the Template tabs Atlas or Mask is active, the corresponding VOIs are also considered. Please enable the Ovr box to see these VOIs in the overlay.
• If a masking operation is configured on the Atlas or Mask sub-tab, it is applied to the contour VOIs during the statistics. Please enable the Fill ROI box to verify the actual coverage of the masked contour VOIs.

VOI Evaluation

The statistics are always calculated using the raw image pixel values, even when the images are shown with smoothing/interpolation enabled. Only full pixels are considered, no partial pixel areas are taken into account. Please enable the Fill checkbox to see which pixels will be included in the statistics calculation.