Abstract: A medical balloon assembly (10) includes a balloon (20) fitted to a balloon catheter (12). The balloon (20) includes a balloon wall (which is a co-extrusion) with ribs or strengthening elements (40) formed of the same polymer material, of a material of the same polymer type or of compatible polymer materials. The ribs in one embodiment extend into the thickness or depth of the balloon wall and in other embodiments may be flattened so as to present a substantially smooth outer surface to the balloon (20). The ribs (40) or strengthening elements may be made of or include radiopaque material.