zero area patch created after extrudemesh
 

I created quasi-2D single cell thickness mesh using salome, and used extrudemesh to create axisymmetric 5 degree mesh

My initial goal was to create it directly from salome, but since unv format can't handle such polyhedral cells inside it, I moved created med file to gmsh and converted again using gmshtofoam, however it couldn't convert it properly since such 'could not match gmsh face' error occured.

Whatever, I exported quasi-2D mesh using unv and used ideaunvtofoam and extrudemesh, and I got wedge mesh

But after that, I got some patch that is invisible from paraview, but still contains 1000 faces which was exact # of faces which was face containing rotating axis at quasi-2D mesh.

How should I deal with this infinitesimal patch? Is it ok to just leave it alone? Or should I do something to remove it?