Method for testing fatigue of a lead

• US 20080178684A1
• Filed: 01/24/2008
• Published: 07/31/2008
• Est. Priority Date: 01/29/2007
• Status: Active Grant

• Current Assignee: Tylerton International Inc.
• Original Assignee: MetaCure Limited (MetaCure (USA), Inc.)
• Inventors: Spehr, Paul Richard
• Granted Patent: US 7,926,358 B2
• Time in Patent Office: Days
• US Class Current: 73/849
• CPC Class Codes: G01N 2203/0023 Bending
• CPC Class Codes: G01N 2203/0073 Fatigue
• CPC Class Codes: G01N 3/32 by applying repeated or pulsating forces

Abstract

A method and apparatus for testing the fatigue of an implantable lead by simultaneously bending and un-bending it at a plurality of successive positions wherein the bending and un-bending positions comprise a substantial length of the lead and wherein the bending radius and sector angle are substantially optional.

Claims

1. A method for testing the fatigue of an implantable lead by simultaneously bending and un-bending it at a plurality of successive positions.

2. A method according to claim 1, wherein the bending and un-bending positions comprise a substantial length of the lead.

3. A method according to claim 1, wherein the bending and un-bending positions comprise approximately the extent of the lead length where bending is expected in the body.

4. A method according to claim 1, wherein the bending and un-bending positions comprise approximately 2 cm.

5. A method according to claim 1, wherein the lead is under a substantial tensile tension.

6. A method according to claim 1, wherein at least a portion of the lead subject to the bending and un-bending is immersed in a solution.

7. A method according to claim 6, wherein the solution concentration is approximately at least the expected concentration of the environment of the lead in the body.

8. A method according to claim 1, wherein the lead comprises at least one electrical contact and wherein voltage and current are applied to the lead at the contact.

9. A method according to claim 8, wherein the current amplitude waveform of said current may vary in time.

10. A method according to claim 9, wherein the current amplitude waveform of said current is approximately at least the expected amplitude waveform of electrical stimulation for the lead in the body.

11. A method according to claim 1, wherein at least part of the bending positions of the lead are maintained at a substantially controlled temperature.

12. A method according to claim 1, wherein

at least a part of the lead is wrapped about a sector of at least one roller;

and

effecting a relative motion between the lead and the roller, in at least one direction substantially length-wise of the lead,

such that the lead successively wraps and bends at one end of a sector and simultaneously un-wraps and is straightened at the other end of the sector.

13. A method according to claim 12, wherein the motion is due to moving a roller along a substantially stationary lead at a plurality of successive positions.

14. A method according to claim 12, wherein the motion is due to moving the lead such that successive positions of the lead come in contact with and leave contact with the roller.

15. A method according to claim 12, wherein the motion is due to rotating a roller about a substantially fixed rotary axis against the lead such that successive positions of the lead come in contact with and leave contact with the roller.

16. A method according to claim 12, wherein the motion is due to rotating and moving the roller against a substantially stationary lead at a plurality of successive positions.

17. A method according to claim 12, wherein separate parts of the lead are wrapped about sectors of a plurality of respective rollers such that more than one portion of the lead is simultaneously bent/straightened.

18. A method according to claim 12, wherein a plurality of leads simultaneously bends and un-bend about at least one roller.

19. A method according to claim 12, wherein the relative motion between a lead and a roller comprises substantially a slippage motion.

20. A method according to claim 12, wherein said roller has a substantially circular cross-section.

21. A method according to claim 12, wherein said roller has a substantially non-circular cross-section.

22. An apparatus for fatigue test of an implantable lead, comprising:

at least one roller mounted on a frame; and

a motor operative to effect a relative motion between a lead wrapped about a sector of the roller and the roller, in at least one direction substantially length-wise of the lead,

such that the lead successively wraps and bends at a plurality of successive positions at one end of a sector and simultaneously un-wraps and un-bends at a plurality of successive positions at the other end.

23. An apparatus according to claim 22, wherein the motor is operative to move the frame such that the roller is moving against a substantially stationary lead.

24. An apparatus according to claim 22, wherein the motor is operative to move the lead against a roller.

25. An apparatus according to claim 22, wherein the lead is maintained with at least non-skid contact with a sector of the roller, and wherein the motor is operative to rotate the roller so that the roller moves the lead about a sector of the roller.

26. An apparatus according to claim 22, wherein the lead is maintained with at least non-skid contact with a sector of the roller, and wherein the motor is mounted on the frame and operative to rotate the roller so that the frame moves with the roller against a substantially stationary lead.

27. An apparatus according to claim 22, wherein a plurality of leads is simultaneously bending and un-bending at a plurality of successive positions.

28. An apparatus according to claim 22, wherein said roller has a substantially circular cross-section.

29. An apparatus according to claim 22, wherein said roller has a substantially non-circular cross-section.