Self-Expanding Prosthesis

• US 20080319525A1
• Filed: 06/25/2008
• Published: 12/25/2008
• Est. Priority Date: 06/25/2007
• Status: Active Grant

• Current Assignee: Microvention Incorporated (Terumo Corporation)
• Original Assignee: Microvention Incorporated (Terumo Corporation)
• Inventors: Tieu, Tai D., Gulachenski, Joseph
• Granted Patent: US 9,023,094 B2
• Time in Patent Office: Days
• US Class Current: 623/1.11
• CPC Class Codes: A61F 2/86 Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2002/823 Stents, different from stent-grafts, adapted to cover an aneurysm
• CPC Class Codes: A61F 2210/0014 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2210/0033 electrically, e.g. heated by resistor

Abstract

In one preferred embodiment, a prosthesis is provided that can be selectively expanded by increasing the temperature of the prosthesis within the patient. The prosthesis is composed of a shape memory material that expands when heated to a temperature greater than an average body temperature, allowing the user to selectively heat and therefore expand the prosthesis at a desired location.

Claims

1. A method of expanding a prosthesis within a body comprising:

providing a prosthesis comprising a shape memory material;

delivering the prosthesis to a desired location within a body;

increasing a temperature of the prosthesis above a human body temperature to change a phase of the shape memory material, thereby expanding said prosthesis to an expanded state;

decreasing said temperature of the prosthesis to the human body temperature while maintaining said expanded state.

2. The method of claim 1, wherein said expanding said prosthesis further comprises expanding a diameter of said prosthesis.

3. The method of claim 1, wherein said increasing a temperature further comprises changing the phase of the shape memory material from a martensitic state to an austensitic state.

4. The method of claim 1, wherein said expanding said prosthesis to an expanded state further comprises:

expanding a first segment of said prosthesis; and

expanding a second segment of said prosthesis.

5. The method of claim 1, wherein said expanding said prosthesis further comprises producing head adjacent to said prosthesis.

6. The method of claim 1, wherein said expanding said prosthesis further comprises producing heat with said prosthesis.

7. The method of claim 1, wherein said delivering said prosthesis to a desired location within a body further comprises:

locating an aneurysm; and

positioning said prosthesis over an opening of said aneurysm.

8. The method of claim 1, wherein said providing a prosthesis comprising a shape memory material is followed by delivering a prosthetic coil within said aneurysm.

9. A prosthesis for deploying within a human body, comprising:

a prosthesis body having a first predetermined shape while in a first phase and a second predetermined shape while in a second phase;

wherein a transition from said first phase to said second phase occurs at a temperature above a human body temperature; and

,

wherein a transition from said second phase to said first phase occurs at a temperature below said human body temperature.

10. The prosthesis of claim 9, wherein said prosthesis body comprises a shape memory material.

11. The prosthesis of claim 9, wherein said first phase is an austenitic state and said second state is a martensitic state.

12. The prosthesis of claim 9, wherein said prosthesis further comprises an active austenite start temperature and an active austenite finish temperature above 37°

C.

13. The prosthesis of claim 12, wherein said active austenite finish temperature is within a range of about 40°

C. and about 55°

C.

14. The prosthesis of claim 9, wherein said prosthesis body further comprises a first segment and a second segment, wherein said first segment is independently expandable relatively to said second segment.

15. The prosthesis of claim 14, wherein said prosthesis further comprises a tubular shape having an interior diameter;

said diameter having a first length during said first predetermined shape and a second, increased length during said second predetermined shape.

16. A prosthesis delivery system comprising:

a delivery tool shaped to enter a body; and

,

a prosthesis removably disposed on said delivery tool;

said prosthesis including a first shape-memory configuration and a second shape-memory configuration;

the prosthesis transitioning from said first shape-memory configuration to said second shape-memory configuration at a temperature above about 37°

C.;

wherein said delivery tool selectively heats said prosthesis within said body.

17. The prosthesis delivery system of claim 16, further comprising at least one heating element disposed on said delivery tool.

18. The prosthesis delivery system of claim 16, wherein said prosthesis further comprises a plurality of independently expandable regions wherein the delivery tool further comprises a plurality of individually actuable heaters.

19. The prosthesis delivery system of claim 18, wherein each of said plurality of independently expandable regions are disposed over a corresponding heater of the plurality of individually actuable heaters.