Of course, Slicer can help in this, too. In its
SlicerRT extension there are sophisticated algorithms to reconstruct closed surfaces from parallel contours, such as your data set.
For example, this is a polydata consisting of parallel contours, shown in Paraview:
You need to save each segment as a .vtp (VTK XML polydata) file, adding field data into each file’s header that indicates that it has to be interpreted as parallel set of contours. The easiest to do it by using a text editor, copy-pasting this into the file header:
<Array type="String" Name="Segmentation_MasterRepresentation" NumberOfTuples="1" format="binary">AQAAAACAAAAPAAAAFwAAAA==eJwLyEnMSyxSSM7PK8kvLWIAAC1zBYk=</Array>
You can also specify segment name, color, etc. in the field data (optional). You can see/edit field data in ParaView using a Spreadsheet view.
Then, you have to create a .vtm file that lists all your .vtp files (using a text editor, it’s a simple text file).
If you drag-and-drop the vtm file into Slicer, then it loads it as segmentation, which you can show and export as closed surface, labelmap, etc. For example, the contour set above imported as segmentation looks like this:
An example set of vtp and vtm files is available here: