A catheter tube carries an operative element, such as, for example, an imaging element to visualize tissue. The catheter tube also carries a support structure, which surrounds the operative element. A steering element moves the operative element relative to the support structure. A guidance element generates an electric field within the support structure, while sensing spatial variations in the electric field during movement of the imaging element. The guidance element generates an output that locates the imaging element relative to the support structure based upon an analysis of the sensed spatial variations. The support structure preferably carries an identification code, which represents the specific spatial geometry of the support structure. The support structure outputs the identification code to the guidance element for consideration when generating the location-specific output.