A catheter has an outer peripheral portion (15) in the form of a tube and an internal wall (16, 26) within the tube forming a plurality of lumens (11a, 11b, 21a, 21b). Axially extending linear contrastradiography sections (17a, 17b, 27a, 27b) of radiopaque material are formed at a plurality of intersection points between the outer peripheral section and the wall, the peripheral extent (a, b) of the respective contrastradiography sections being different.
