Elastic Registration

[Zah]

Hi 3D Slicer Community,

I’m new to 3D Slicer and still learning, and I have a few questions.

1. After performing an elastic registration, should I harden the transformed CBCT using the “Transforms” module, or should this be done from the “Data” module?

2. When I save my data and reopen the scene, I don’t get the same results.
   Is there a recommended or specific way to save all transformed volumes and segmentations to ensure everything loads correctly?

3. After applying an elastic transformation, how can I extract the deformation matrix or deformation field?
   I would like to quantify the deformation if possible.

4. Finally, is there any method other than “Segment Cross-Section Area” to compare bone gain before and after grafting?
   I’m looking for reliable ways to quantify volumetric changes.

Thank you very much for your help.

[muratmaga]

@Zah

After performing an elastic registration, should I harden the transformed CBCT using the “Transforms” module, or should this be done from the “Data” module?

These are equivalent, doesn’t matter where you it.

@Zah

When I save my data and reopen the scene, I don’t get the same results.

That shouldn’t be the case. Are you sure you are saving all the objects associated with the scene?

@Zah

After applying an elastic transformation, how can I extract the deformation matrix or deformation field?

Deformation field will be saved as a transform. You can then turn that into a grid transform or displacement field, depending on how you want to quantify the deformation. There are no specific tools to quantify deformation in Slicer, as far as I know.