Bend-responsive catheter

• US 6,272,371 B1
• Filed: 02/22/1999
• Issued: 08/07/2001
• Est. Priority Date: 01/03/1997
• Status: Expired due to Term

• Current Assignee: Biosense, Inc. (Cardinal Health, Inc.)
• Original Assignee: Biosense, Inc. (Cardinal Health, Inc.)
• Inventors: Shlomo, Ben-Haim
• Primary Examiner(s): Smith, Ruth S.
• Application Number:
  US09/125,932
• Time in Patent Office: 897 Days
• Field of Search: 600/117, 600/424, 128/899, 607/122
• US Class Current: 600/424
• CPC Class Codes: A61B 1/0051 with controlled bending of insertion part
• CPC Class Codes: A61B 1/009 with bending or curvature detection of the insertion part
• CPC Class Codes: A61B 17/3403 Needle locating or guiding means guides for suture needles A61B17/0482; guiding or tracking by nuclear magnetic resonance G01R33/285
• CPC Class Codes: A61B 18/24 with a catheter A61B18/26, A61B18/28 take precedence
• CPC Class Codes: A61B 2017/00243 cardiac
• CPC Class Codes: A61B 2017/00247 Making holes in the wall of the heart, e.g. laser Myocardial revascularization
• CPC Class Codes: A61B 2018/00392 Transmyocardial revascularisation
• CPC Class Codes: A61B 2018/2272 with reflective or refractive surfaces for deflecting the beam A61B2018/2261, A61B2018/2266 take precedence
• CPC Class Codes: A61B 2034/2051 Electromagnetic tracking systems
• CPC Class Codes: A61B 2090/3954 magnetic, e.g. NMR or MRI
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 5/06 Devices, other than using radiation, for detecting or locating foreign bodies for removing same A61B17/50 ; determining position of probes within or on the body of the patient
• CPC Class Codes: A61B 5/061 Determining position of a probe within the body employing means separate from the probe, e.g. sensing internal probe position employing impedance electrodes on the surface of the body A61B1/00158 takes precedence
• CPC Class Codes: A61B 5/065 Determining position of the probe employing exclusively positioning means located on or in the probe, e.g. using position sensors arranged on the probe
• CPC Class Codes: A61B 5/287 Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61B 5/6885 Monitoring or controlling sensor contact pressure
• CPC Class Codes: A61B 8/0833 involving detecting or locating foreign bodies or organic structures
• CPC Class Codes: A61M 2025/0166 Sensors, electrodes or the like for guiding the catheter to a target zone, e.g. image guided or magnetically guided
• CPC Class Codes: A61M 25/0041 pre-formed, e.g. specially adapted to fit with the anatomy of body channels urethral catheters A61F2/04
• CPC Class Codes: A61M 25/01 Introducing, guiding, advancing, emplacing or holding catheters A61M25/10 takes precedence
• CPC Class Codes: A61M 25/0105 : Steering means as part of the catheter or advancing means; Markers for positioning systems for detection of markers A61B
• CPC Class Codes: A61M 25/0133 : Tip steering devices
• CPC Class Codes: A61N 1/05 : for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence

Abstract

This invention is an invasive probe apparatus including flexible elongate probe (20) having a distal portion adjacent to a distal end (22) thereof for insertion into the body of a subject, which portion assumes a predetermined curve form when a force is applied thereto. First and second sensors (28, 30) are fixed to the distal portion of the probe (20) in known positions relative to the distal end (22), which sensors generate signals responsive to bending of the probe. Signal processing circuitry (36) receives the bend responsive signals and processes them to find position and orientation coordinates of at least the first sensor (28), and to determine the locations of a plurality of points along the length of the distal portion of the probe.

Claims

1. Invasive probe apparatus for use with an externally-applied magnetic field, the probe comprising:

a flexible, elongate probe, having a distal portion adjacent to a distal end thereof, for insertion into the body of a subject, which portion assumes a predetermined, curved form when a force is applied thereto;

a first sensor and a second sensor, fixed to the distal portion of the probe in known positions relative to the distal end, which sensors generate signals, the first sensor being a magnetic-field responsive sensor as a first position-sensing element for generating a first signal to enable determination of position and orientation coordinates of the first position-sensing element, said first signal defining a position and orientation coordinate signal, and the second sensor being a bend-sensing element for generating a second signal responsive to bending of the probe, said second signal defining a bend signal; and

signal processing circuitry, which receives the position and orientation coordinate signal and the bend signal and processes them to find position and orientation coordinates of at least the first sensor and to determine the locations of a plurality of points along the length of the distal portion of the probe.

2. Apparatus according to claim 1, wherein the first sensor comprises three coils, which generate signals responsive to the externally-applied magnetic field.

3. Apparatus according to claim 1, wherein the probe has a generally constant elasticity over the length of the distal portion thereof.

4. Apparatus according to claim 1, wherein the probe comprises a resilient longitudinal member.

5. Apparatus according to claim 4, wherein the bend-sensing element generates signals responsive to a direction of bending of the probe.

6. Apparatus according to claim 4, wherein the bend-sensing element comprises at least one piezoelectric crystal.

7. Apparatus according to claim 6, wherein the at least one piezoelectric crystal comprises three such crystals, each crystal having an axis, wherein the axes are mutually orthogonal.

8. Apparatus according to claim 4, wherein the bend-sensing element comprises a fiberoptic sensor.

9. Apparatus according to claim 4, wherein the bend-sensing element comprises a strain sensor.

10. Apparatus according to claim 4, wherein the signal processing circuitry determines a radius of curvature of the probe.

11. Apparatus according to claim 4, wherein the signal processing circuitry determines a radius and a pitch of a helical form described by the probe.

12. Apparatus according to claim 4, wherein the probe comprises a deflection device within the distal portion thereof.

13. Apparatus according to claim 1, wherein the second sensor comprises a magnetic-field responsive sensor as a second position-sensing element.

14. Apparatus according to claim 13, wherein the signal processing circuitry processes the signals generated by the second sensor to find position and orientation coordinates thereof.

15. Apparatus according to claim 14, wherein the position and orientation coordinates found by the signal processing circuitry comprise six-dimensional position and orientation coordinates.

16. A method for determining the course of an elongate, flexible probe inside the body of a subject through the use of an externally-applied magnetic field, comprising:

generating an externally-applied magnetic field;

finding position and orientation coordinates of a point on the probe using at least one magnetic field responsive sensor on the probe;

measuring a bending angle of a portion of the probe adjacent to the point; and

processing the position and orientation coordinates and the bending angle to determine the locations of a plurality of points along the length of a portion of the probe inside the body.

17. A method according to claim 16, wherein finding position and orientation coordinates comprises finding six-dimensional position and orientation coordinates.

18. A method according to claim 16, wherein measuring a bending angle comprises finding position coordinates of an additional point on the probe.

19. A method according to claim 16, wherein measuring a bending angle comprises measuring a force associated with bending the probe.

20. A method according to claim 19, wherein processing the position coordinates and the bending angle comprises calculating a radius of curvature of the probe.

21. A method according to claim 19, wherein processing the position coordinates and the bending angle comprises calculating a radius of a helical path described by the probe.

22. A catheter comprising:

an elongated member;

a proximal position sensor on a distal end of the member;

a distal position sensor on the distal end and spaced a distance from the proximal position sensor, the proximal position sensor and the distal position sensor generating signals to enable determination of position coordinates of the proximal position sensor and the distal position sensor respectively; and

a bend portion between the proximal position sensor and the distal position sensor, wherein position coordinates of the proximal position sensor and the distal position sensor are used to determine a radius of curvature for the bend portion, the radius of curvature defining an arc and the bend portion following the arc upon a bending of the bend portion such that a position of any point on the bend portion can be determined.

23. The catheter according to claim 22, wherein at least one of the proximal position sensor and the distal position sensor is a magnetic field sensor.

24. The catheter according to claim 22, wherein at least one of the proximal position sensor and the distal position sensor is an acoustic sensor.

25. The catheter according to claim 22, wherein at least one of the proximal position sensor and the distal position sensor is an electrical sensor.

26. The catheter according to claim 22, further comprising a physiological sensor.

27. The catheter according to claim 26, further comprising a therapeutic device.

28. The catheter according to claim 27, wherein at least one of the proximal position sensor and the distal position sensor is a magnetic field sensor.

29. The catheter according to claim 27, wherein at least one of the proximal position sensor and the distal position sensor is an acoustic sensor.

30. The catheter according to claim 27, wherein at least one of the proximal position sensor and the distal position sensor is an electrical sensor.