A catheter (1) adapted to cross occlusions in vessels of a patient. The catheter is having a proximal end reversibly insertable adjacent to the occlusion and a distal opposite end located outside the patient. When the pusher (10) in the OPEN configuration, it provides a preset void volume barriered by means of the pusher, the proximal end of the catheter and the inner surface of the vessel. The vacuum generating mechanism applies suction on the occlusion and on the inner surface of the vessel through the void volume, to collapse and fix the tissues around the pusher and to stabilize the pusher of the catheter so that the occlusion can be penetrated with a guide-wire (13).
