An expander is provided for radially expanding a tubular element, the expander having an axially forward direction and being provided with thrust means for exerting a thrust force to the expander to move the expander in axially forward direction through the tubular element. The convoluted side surfaces and variable-width working surface features permit the impression left by one die blade to fill space taken from an impression made by a laterally adjacent die blade. Adjustment may be achieved by use of bulking agents applied either directly to the site or into a containment device located within proximity of the tape and such that it works in conjunction with the tape to support the anatomic structure. The control can be provided by using a look up table. Further, the length of the apparatus can be varied so that the outlet valve can be easily accessed andor the gauge can be easily viewed. The displaying unit executes processing of displaying output data in response to a selecting mode of the display selecting unit.