Abnormal segmentation behavior

i had this recurring behavior lately . other segments disappearing upon new segments editing or creation

You are editing Segment-2 while capillary segmentation is selected. Probably, when you make changes (edits) on " Segment-2 (but actually capillary)", it probably overwrites all visible segments (probably due to your segmentation settings). if the area you are editing has different HU values than Segment 2 (as a setting), then any changes you are going to make (even a single pixel) on Segment 2 while “capillary” is selected will overwrite the visible segment.

Solution: If you intended to make changes to segment 2, just unselect all others (including capillary), then select segment 2 and proceed with your editing like that.

I hope that helps.

thank you for response

my workflow is the following
segment mandible ( segment 2) using threshold/paint ( everywhere )
segment condyle (capillary) : threshold/paint ( inside segment 2 + allow overlap )

i used this workflow many times before and was fine.

which part of the segmentation setting will erase the whole segment despite “allow overlap”?

Did the segments actually change (e.g., also disappeared in slice views as well) or it was just a rendering issue in the 3D view?

Only in rendering in view 1. View 2 is not affected

What Slicer version is this?

Do you have an Apple silicon (ARM) system? Apple’s intel emulator does not seem very robust. Maybe upgrading your system will fix the issue.

Can you reproduce the behavior if you save the scene, restart Slicer, and load the scene?
Can you reproduce it on a different computer? (or can you share the scene with us so that we can try it on different computers)

Slicer 5.5 but happened more frequent before on 5.4 on Mac m2 .
I don’t have access to other computer .
Once the rendering issues occurs it’s permanent . Even after restart and opening the scene , rendering will not show on view 1 .
The error only occurs once per scene .

This is great! Any problems that we can reproduce we can fix. Could you share this scene file (upload somewhere and post the link here)? Make sure the image is anonymized (no protected health information is included).

I was able to reproduce the issue. I’ve submitted a bug report here:

@Sunderlandkyl would you be able to work on it? It seems that it is due to some modified event triggered by modification of a shared labelmap representation.


The issue is now fixed in the latest preview release with this PR: BUG: Fix closed surface disappearing when segment is removed by Sunderlandkyl · Pull Request #7226 · Slicer/Slicer · GitHub.

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