Dear Andras,
I used segment mesher. It is generating surface mesh instead of volumetric mesh. I used segment editor for segmenting tumor and brain. then I switched to segment mesher. It always generate surface mesh. I opened the *.vtk file of the generated model into paraview but dont see a volumetric mesh.
Please see the screen shot.
Does segmentmesher do not produce volumetric mesh? if yes what am I doing wrong? would you please correct me?