Changing dimensions of the mesh

Hi,

How do you change the existing dimesnions of mesh into new one, for example, I have a model of a curved and non-symmetrical pipe. I meshed the existing pipe and now I want to change external and internal radius of pipe but I don't want to go back in Catia or Solidworks, instead of that is it possible to change the dimensions(radii) of mesh itself?

Thanks, Petar