How to make a tumor model in a 3D CT data?

Hi, I am trying a CT imaging simulation project. And I want to use 3Dslicer to build up a tumor model. The conception is inserting a small ball as the tumor model into the current brain model. And export it as a voxelized phantom. Could anyone help me or give some hints?

You can paint a tumor using Paint effect in Segment Editor module. If you enable “sphere brush” option then you can create a tumor model by a single click. Then you can paint that segment into the CT using Mask volume effect.

If you want to simulate a more realistic shape or texture then it should be easy to do, too. You can get the image and mask of a segmented tumor as numpy arrays and combine them with voxels of another volume using standard numpy operations. See useful examples in the script repository.

Hi, Andras, Thank you for the great advices!
I tried to use the Paint effect with “sphere brush” in the Digimouse model, as the red ball bellow, and click Mask volume.
Then I add the skin segment and adjust the skin opacity in Segmentations, to make the organ visible. But the red ball is invisible. Could you tell me why?

Mask volume modifies the chosen input volume and generates an output volume where the region inside (or outside) of the segment is set to a specific intensity. This can be used to simulate a tumor that looks more dense or contrast-enhanced on the image.

If you successfully add a sphere-shaped segment then it will be displayed in views and adjusting opacity should not affect its visibility. Depending on the opacity value, you may need to enable depth peeling to ensure transparent segments embedded into each other are displayed correctly.

I found the solution to this problem. The sphere segment shoud be done after adding the skin segment. To my understanding, mask volume is Blank out the selected skin segment.