Vertebral Foramen Segmentation with Fill between Slices

Trying to segment the vertebral space in this image where I’ve already segmented out the lumbar spine.

I found that fill between slices works moderately well, (see image)

fill_btwn_slices1

however upon initializing you can see how the rest of the segments grow, and I can’t select islands to remove this growth and I don’t know how to lock those segments so only the vertebral space grows.

Unfortunately I can’t always segment out the space as it’s not always straight (seen here)

fill_btwn_slices2

and the CT data isn’t the best resolution for segmenting out the spinal column as some other form of help here.

  • How can I fill slices on just one segmentation without influencing the others?
  • Or what other tricks can I use to get this segmentation nicely?