Systems for use in crossing and treating an occlusion

1. A catheter device for crossing an occlusion within a blood vessel or cylindrical body cavity, the catheter device comprising:

a proximal portion to be disposed outside a patient in use;

a distal portion to be advanced from outside a patient to a proximal face of an occlusion;

an elongate body extending between the proximal portion and the distal portion and to a distal-most end of the catheter device, the elongate body having a lumen extending therethrough with an inner diameter configured for sliding over the guidewire, the elongate body being sufficiently stiff to transmit torque for reciprocating action of the distal end, wherein an inner surface of the elongate body is configured to be advanced directly over guidewire;

a rigid ring having an inside surface fixedly attached to and disposed radially outwardly of an outside surface of the distal portion, an outside surface of the rigid ring having a radius that is greater than a radius of an outside surface of an adjacent portion of the elongate body, the adjacent portion being proximal of the rigid ring, the rigid ring having an occlusion reducing feature rotationally fixed to a distal end thereof, a distal end of the occlusion reducing feature being longitudinally aligned with or proximal of the distal-most end of the elongate body; and

a handle coupled with the proximal portion;

wherein the catheter device is configured to enlarge a lumen through the occlusion.

2. The system of claim 1 , wherein the rigid ring retains a minimum transverse dimension of at least about 90% of an at rest diameter thereof upon action against the occlusion whereby deformation of an inner passage thereof during interaction with the occlusion is minimal such that relative movement between the guidewire and the rigid ring are preserved.

3. The system of claim 1 , the catheter device further comprising an interface disposed between the elongate body and the rigid ring, the interface comprising at least one opening disposed in the rigid ring and a radial projection extending into the opening such that the projection is axially overlapping with at least a portion of the opening;

wherein the catheter is configured such that rotation or translation of the handle is transmitted to the occlusion at least partially along or through the interface.

4. The system of claim 1 , wherein the elongate body is configured to transmit torque applied to the proximal end 1:1 to the rigid ring.

5. The system of claim 1 , wherein the catheter device is configured to support the guidewire in a first mode and to enlarge a lumen through the occlusion in a second mode.

6. The system of claim 1 , wherein the rigid ring has a continuously convex outer periphery as viewed from an end thereof.

7. The system of claim 1 , wherein the occlusion reducing feature comprises a plurality of teeth formed on the distal end of the rigid ring.

8. The system of claim 7 , wherein the teeth comprise an asymmetric shape having an axial edge and a circumferential edge.

9. The system of claim 7 , wherein the teeth are configured to abrade without cutting, tearing, or slicing.

10. A system for crossing an occlusion within a blood vessel or cylindrical body cavity, comprising:

a guidewire; and

a catheter device, comprising:

an elongate body comprising an inner surface that surrounds a lumen that extends from a proximal end to a distal end of the elongate body, the inner surface of the elongate body configured to be advanced directly over the guidewire, the elongate body further comprising an outer surface that extends from the proximal end to the distal end of the elongate body;

a rigid ring that surrounds the distal end of the elongate body and is fixedly attached to the outer surface of the elongate body, the rigid ring being cylindrical in shape and comprising an abrasive edge disposed at a distal end thereof and rotationally fixed relative to the rigid ring, the distal end of the rigid ring being longitudinally aligned with or proximal to the distal end of the elongate body, an outside surface of the rigid ring having a radius that is greater than a radius of an adjacent portion of the outer surface of the elongate body, the adjacent portion being proximal of the rigid ring; and

a handle at the proximal end of the elongate body, wherein the handle is fixedly attached to the outer surface of the elongate body precluding relative rotation therebetween, wherein in use the handle is used to transmit a torque to the rigid ring.

11. The system of claim 10 , wherein the distal face of the implement is blunt.

12. The system of claim 10 , further comprising a sheath configured to slideably receive and to be disposed circumferentially about the catheter device such that the catheter device can be delivered to a lesion without being exposed to the vasculature.

13. The system of claim 10 , wherein the rigid ring is configured to withstand an axial compressive force of 10 Newton applied at the distal end of the rigid ring.

14. The system of claim 10 , wherein the rigid ring comprises a plurality of teeth formed on the abrasive edge.

15. The system of claim 14 , wherein the teeth comprise an asymmetric shape having an axial edge and a circumferential edge.

16. The system of claim 10 , the catheter device further comprising an interface disposed between the elongate body and the rigid ring, the interface comprising at least one opening disposed in the rigid ring and a radial projection extending into the opening such that the projection is axially overlapping with at least a portion of the opening;

wherein the catheter is configured such that rotation or translation of the handle is transmitted to the occlusion at least partially along or through the interface.

17. The system of claim 10 , wherein the elongate body is configured to transmit torque applied to the proximal end 1:1 to the rigid ring.