System for guiding devices in body lumens

• US 5,904,657 A
• Filed: 02/26/1997
• Issued: 05/18/1999
• Est. Priority Date: 02/26/1997
• Status: Expired due to Fees

• Current Assignee: Allan G. Adelman, John D. Unsworth, Thomas C. Waram
• Original Assignee: Allan G. Adelman, John D. Unsworth, Thomas C. Waram
• Inventors: Unsworth, John D., Waram, Thomas C, Adelman, Allan G
• Primary Examiner(s): Hindenburg, Max
• Assistant Examiner(s): MARMOR II, CHARLES ALAN
• Application Number:
  US08/806,793
• Time in Patent Office: 811 Days
• Field of Search: 600/434, 600/585, 604/95, 604/96, 604/280, 604/281, 606/1, 606/7, 606/15, 606/16, 606/17
• US Class Current: 600/585
• CPC Class Codes: A61M 2025/0161 wherein the distal tips have two or more deflection regions
• CPC Class Codes: A61M 2025/09116 Design of handles or shafts or gripping surfaces thereof for manipulating guide wires
• CPC Class Codes: A61M 25/0155 with hydraulic or pneumatic means, e.g. balloons or inflatable compartments
• CPC Class Codes: A61M 25/0158 with magnetic or electrical means, e.g. by using piezo materials, electroactive polymers, magnetic materials or by heating of shape memory materials
• CPC Class Codes: A61M 25/09 Guide wires

Abstract

A system for guiding devices or materials into body lumens includes a guidewire made of a shape memory alloy (SMA) or other shape memory material and having a lumen; an energy guide, preferably an optical fiber, received in the lumen; and a catheter or device slidably attached to the guidewire. The guidewire has a memorized shape and is in a martensitic (deformable) state during insertion into the body lumen. During or after insertion of the guidewire into the body lumen, the energy guide produces localized heating of the inner surface of the distal end of the guidewire, to cause the guidewire to at least partially recover its memorized shape, thereby selectively changing the shape, radii of curves, and rigidity of part or all of the guidewire. This selective shaping of the guidewire reduces fouling and facilitates delivery of devices along the guidewire.

Claims

1. A system for guiding devices or materials into body lumens, comprising:

a guidewire having a proximal end, a distal end spaced from the proximal end, and one or more lumens extending through the guidewire from the proximal end to approximately the distal end, wherein said guidewire is comprised of a shape memory alloy (SMA) or other shape memory material and has a memorized shape which is relaxed by the extraction of thermal energy and is at least partly recovered with the application of thermal energy;

heating means adapted for selective, localized heating of said guidewire to thereby straighten and stiffen all or part of said guidewire; and

a catheter or device, that is slidably attached to said guidewire, and that is adapted to be slid along said guidewire into a body lumens; and

wherein said heating means comprises an optical fiber extending through one of the lumens of the guidewire, said optical fiber having a proximal end and a distal end, said optical fiber being adapted to deliver photo-thermal energy along the optical fiber.

2. The system of claim 1, wherein the distal end of the optical fiber is provided with redirecting means which re-direct and project said photo-thermal onto an inner surface of said lumen of the guidewire.

3. The system of claim 1, wherein said optical fiber further has a lumen extending from said proximal end to said distal end of said optical fiber, said lumen of said optical fiber being adapted to deliver heating or cooling fluids or both from the proximal end to the distal end of the optical fiber.

4. The system of claim 3, wherein said optical fiber includes means for redirecting flow of said fluids normal to a longitudinal axis of said optical fiber.

5. The system of claim 1, wherein the guidewire is made of a shape memory alloy (SMA) material that is deformable from a previously memorized shape in a deformation state selected from one or more of bending, tension and torsion, and at a temperature at or above an austenite finish temperature of the SMA material such that the SMA material exhibits superelastic behavior by forming stress-induced martensite or exhibits pure elastic behavior, or some combination of both superelastic and elastic behavior in different areas or layers of the guidewire, and wherein the application of thermal energy causes the SMA material to increase in temperature, which causes the stiffness of the guidewire to increase and thereby attempt to resume its memorized shape either by a concomitant increase in elastic modulus of the SMA material or by an increase in a value of a superelastic stress plateau, which is a stress at which the stress-induced martensite is first formed, or by a combination thereof, or other more complex deformation and recovery paths occurring as a function of stress, strain and temperature, including complex subloops at temperatures at or above the austenite finish temperature of the SMA material.

6. The system of claim 5, wherein the SMA material is a nickel/titanium alloy.

7. A system for guiding devices or materials into body lumens, comprising:

a guidewire having a proximal end, a distal end spaced from the proximal end, and one or more lumens extending through the guidewire from the proximal end to approximately the distal end, wherein said guidewire is comprised of an inner tube enclosed within an outer tube along at least a part of its length, each of the inner tube and the outer tube comprising a shape memory alloy (SMA) or other shape memory material and having a memorized shape which is relaxed by the extraction of thermal energy and is at least partly recovered with the application of thermal energy wherein, during shape recovery, one of said tubes is in compression parallel to its longitudinal axis and the other of said tubes is in tension parallel to its longitudinal axis;

heating means adapted for selective, localized heating of said guidewire to thereby change the shape, the radii of its curves and the rigidity of all or part of said guidewire; and

a catheter or device, that is slidably attached to said guidewire, and that is adapted to be slid along said guidewire into a body lumens.

8. The system of claim 7, wherein said heating means comprises an optical fiber extending through one of the lumens of the guidewire, said optical fiber having a proximal end and a distal end, said optical fiber being adapted to deliver photo-thermal energy along the optical fiber.

9. The system of claim 8, wherein the distal end of the optical fiber is provided with redirecting means which re-direct and project said photo-thermal energy onto an inner surface of said lumen of the guidewire.

10. The system of claim 8, wherein said optical fiber further has a lumen extending from said proximal end to said distal end of said optical fiber, said lumen of said optical fiber being adapted to deliver heating or cooling fluids or both from the proximal end to the distal end of the optical fiber.

11. The system of claim 10, wherein said optical fiber includes means for redirecting flow of said fluids normal to a longitudinal axis of said optical fiber.

12. The system of claim 7, wherein the guidewire is deformable from a previously memorized shape in a deformation state selected from one or more of bending, tension and torsion, and at a temperature at or above an austenite finish temperature of the SMA material such that the SMA material exhibits superelastic behavior by forming stress-induced martensite or exhibits pure elastic behavior, or some combination of both superelastic and elastic behavior in different areas or layers of the guidewire, and wherein the application of thermal energy causes the SMA material to increase in temperature, which causes the stiffness of the guidewire to increase and thereby attempt to resume its memorized shape either by a concomitant increase in elastic modulus of the SMA material or by an increase in a value of a superelastic stress plateau, which is a stress at which the stress-induced martensite is first formed, or by a combination thereof, or other more complex deformation and recovery paths occurring as a function of stress, strain and temperature, including complex subloops at temperatures at or above the austenite finish temperature of the SMA material.

13. The system of claim 12, wherein the SMA material is a nickel/titanium alloy.

14. A system for guiding devices or materials into body lumens, comprising:

a guidewire having a proximal end, a distal end spaced from the proximal end, and one or more lumens extending through the guidewire from the proximal end to approximately the distal end, wherein said guidewire is comprised of an inner tube enclosed within an outer tube along at least a part of its length, each of the inner tube and the outer tube comprising a shape memory alloy (SMA) or other shape memory material and having a memorized shape which is relaxed by the extraction of thermal energy and is at least partly recovered with the application of thermal energy wherein, during shape recovery, one of said tubes is in compression radially, normal to its longitudinal axis, and the other of said tubes is in tension radially, normal to its longitudinal axis;

heating means adapted for selective, localized heating of said guidewire to thereby change the shape, the radii of its curves and the rigidity of all or part of said guidewire; and

a catheter or device, that is slidably attached to said guidewire, and that is adapted to be slid along said guidewire into a body lumens.

15. The system of claim 14, wherein said heating means comprises an optical fiber extending through one of the lumens of the guidewire, said optical fiber having a proximal end and a distal end, said optical fiber being adapted to deliver photo-thermal energy along the optical fiber.

16. The system of claim 15, wherein the distal end of the optical fiber is provided with redirecting means which re-direct and project said photo-thermal energy onto an inner surface of said lumen of the guidewire.

17. The system of claim 15, wherein said optical fiber further has a lumen extending from said proximal end to said distal end of said optical fiber, said lumen of said optical fiber being adapted to deliver heating or cooling fluids or both from the proximal end to the distal end of the optical fiber.

18. The system of claim 17, wherein said optical fiber includes means for redirecting flow of said fluids normal to a longitudinal axis of said optical fiber.

19. The system of claim 14, wherein the guidewire is deformable from a previously memorized shape in a deformation state selected from one or more of bending, tension and torsion, and at a temperature at or above an austenite finish temperature of the SMA material such that the SMA material exhibits superelastic behavior by forming stress-induced martensite or exhibits pure elastic behavior, or some combination of both superelastic and elastic behavior in different areas or layers of the guidewire, and wherein the application of thermal energy causes the SMA material to increase in temperature, which causes the stiffness of the guidewire to increase and thereby attempt to resume its memorized shape either by a concomitant increase in elastic modulus of the SMA material or by an increase in a value of a superelastic stress plateau, which is a stress at which the stress-induced martensite is first formed, or by a combination thereof, or other more complex deformation and recovery paths occurring as a function of stress, strain and temperature, including complex subloops at temperatures at or above the austenite finish temperature of the SMA material.

20. The system of claim 19, wherein the SMA material is a nickel/titanium alloy.