An anchoring device (1) for anchoring a boring tool (3) in a lumen (4) for boring through an occlusion (6) in the lumen (4) comprises an expandable element (18) adapted for securing to a balloon (12) of a balloon catheter (8) adjacent a distal end (7) thereof. The expandable element (18) is expandable and contractible with the balloon (12) of the balloon catheter (8) for engaging the lumen and for anchoring the anchoring device (1) in the lumen (4). A guide element (33) extends coaxially from the expandable element (18), and a guide bore (34) extending through the guide element (33) is provided with an internal primary screw thread (35) for engaging a corresponding external screw thread (36) on the boring tool (3). A carrier wire (45) extends from the boring tool (3) through a central lumen (15) of the balloon catheter (8), so that rotation of the boring tool (3) by the guide wire (45) when the threads (35,36) are engaged results in the boring tool being urged through the occlusion (6) for forming an opening therethrough.
