Food for thought... According to Andy, there's nothing quite like eating your own chocolate brain, but we'll have to take his word for that... If yo...
Step 2: DICOM Data Model Export
Once InVesalius has calculated the model, you can adjust the settings to select only the brain. We did this by filtering out everything but fat tissue then adjusting the levels to select as much of the brain as possible.
Don't worry if other parts are selected - these can be removed later.
Once you are happy with your selection, save out as an STL file.