SurfaceToSurfaceDistance output

I just want to know what the SurfaceToSurfaceDistance output is? I was running it but there is not output file. I What type of file should we pass in OutFileName?

It should be a ‘.vtk’ file. You can output the surface distance from a → b and b ->a:

(-A , --outputA) OutputAFileName
(-B , --outputB) OutputBFileName