Systems for tissue ablation and aspiration

• US 6,254,600 B1
• Filed: 06/11/1999
• Issued: 07/03/2001
• Est. Priority Date: 05/10/1993
• Status: Expired due to Term

• Current Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Original Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Inventors: Ngo, Jimmy V., Eggers, Philip E., Thapliyal, Hira V., Davison, Terry S., Willink, Christopher L., Olsen, Phillip M.
• Primary Examiner(s): COHEN, LEE S
• Application Number:
  US09/330,275
• Time in Patent Office: 753 Days
• Field of Search: 606/41, 606/45, 606/46, 606/48, 606/49, 606/50, 604/35, 604/114, 607/99, 607/105, 607/113
• US Class Current: 606/41
• CPC Class Codes: A61B 18/12 by passing a current through the tissue to be heated, e.g. high-frequency current
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• CPC Class Codes: A61B 18/148 having a short, rigid shaft for accessing the inner body transcutaneously, e.g. for neurosurgery or arthroscopy
• CPC Class Codes: A61B 18/1482 having a long rigid shaft for accessing the inner body transcutaneously in minimal invasive surgery, e.g. laparoscopy
• CPC Class Codes: A61B 18/1485 having a short rigid shaft for accessing the inner body through natural openings
• CPC Class Codes: A61B 18/149 bow shaped or with rotatable body at cantilever end, e.g. for resectoscopes, or coagulating rollers
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2017/00026 Conductivity or impedance, e.g. of tissue
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61B 2017/00101 using an array of thermosensors
• CPC Class Codes: A61B 2017/00247 Making holes in the wall of the heart, e.g. laser Myocardial revascularization
• CPC Class Codes: A61B 2018/00029 open
• CPC Class Codes: A61B 2018/00083 low, i.e. electrically insulating
• CPC Class Codes: A61B 2018/00119 with metal oxide nitride
• CPC Class Codes: A61B 2018/0016 Energy applicators arranged in a two- or three dimensional array
• CPC Class Codes: A61B 2018/00178 Electrical connectors
• CPC Class Codes: A61B 2018/00327 Ear, nose or throat
• CPC Class Codes: A61B 2018/00392 Transmyocardial revascularisation
• CPC Class Codes: A61B 2018/00505 Urinary tract
• CPC Class Codes: A61B 2018/00577 : Ablation
• CPC Class Codes: A61B 2018/00583 : Coblation, i.e. ablation using a cold plasma
• CPC Class Codes: A61B 2018/0066 : without feedback, i.e. open loop control
• CPC Class Codes: A61B 2018/00666 : using a threshold value
• CPC Class Codes: A61B 2018/00678 : upper
• CPC Class Codes: A61B 2018/00702 : Power or energy
• CPC Class Codes: A61B 2018/0072 : Current
• CPC Class Codes: A61B 2018/00726 : Duty cycle
• CPC Class Codes: A61B 2018/00779 : Power or energy
• CPC Class Codes: A61B 2018/00791 : Temperature
• CPC Class Codes: A61B 2018/00827 : Current
• CPC Class Codes: A61B 2018/00875 : Resistance or impedance
• CPC Class Codes: A61B 2018/00982 : combined with or comprising means for visual or photographic inspections inside the body, e.g. endoscopes
• CPC Class Codes: A61B 2018/1213 : creating an arc
• CPC Class Codes: A61B 2018/124 : switching the output to different electrodes, e.g. sequentially
• CPC Class Codes: A61B 2018/1253 : monopolar
• CPC Class Codes: A61B 2018/126 : bipolar
• CPC Class Codes: A61B 2018/1273 : including multiple generators in one device
• CPC Class Codes: A61B 2018/1467 : using more than two electrodes on a single probe
• CPC Class Codes: A61B 2018/1472 : for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61B 2018/162 : located on the probe body
• CPC Class Codes: A61B 2018/165 : Multiple indifferent electrodes
• CPC Class Codes: A61B 2218/002 : Irrigation
• CPC Class Codes: A61B 2218/007 : Aspiration
• CPC Class Codes: A61F 2/2493 : Transmyocardial revascularisation [TMR] devices

Abstract

The present invention provides systems and methods for selectively applying electrical energy to a target location within or on a patient'"'"'s body. In particular, methods and apparatus are provided for resecting, cutting, partially ablating, aspirating or otherwise removing tissue from a target site, and ablating the tissue in situ. The methods and systems of the present invention are particularly useful for removing tissue within joints, e.g., synovial tissue, meniscus, articular cartilage and the like.

Claims

1. An electrosurgical instrument for removing tissue from a target site within or on a patient'"'"'s body comprising:

a shaft having proximal and distal end portions and an active electrode on the distal end portion, the active electrode comprising a substantially planar tissue treatment surface;

a return electrode on the shaft spaced from the active electrode;

an aspiration lumen within the shaft having a distal opening at the distal end portion of the shaft; and

wherein the active electrode extends across a portion of the distal opening of the aspiration lumen to inhibit clogging of the lumen and wherein the active electrode comprises an L-shaped electrode having a first portion extending axially from the distal end portion of the shaft and a second portion continuous with, and perpendicular to, the first portion, the second portion having a substantially planar surface opposite the shaft.

2. The instrument of claim 1 wherein the active electrode comprises a peripheral surface facing a direction substantially perpendicular to the planar tissue treatment surface, wherein the active electrode is configured to ablate tissue adjacent to the tissue treatment surface and tissue adjacent to the peripheral surface.

3. The instrument of claim 2 wherein the peripheral surface extends 360 degrees around the active electrode.

4. The instrument of claim 1 further comprising a plurality of active electrodes extending across the distal opening of the aspiration lumen and together forming the substantially planar tissue treatment surface.

5. The instrument of claim 1 further comprising three L-shaped electrodes, each having a first portion extending axially from the distal end portion of the shaft, and a second portion extending across the distal opening of the aspiration lumen.

6. The instrument of claim 1 further comprising an electrically insulating support member between the active and return electrodes, the support member comprising an inorganic material.

7. The instrument of claim 6 wherein the support member has an axial opening in communication with the aspiration lumen.

8. The instrument of claim 1 wherein the return electrode is spaced from the active electrode such that, when the active electrode is brought adjacent a tissue structure immersed in electrically conductive fluid, the active electrode is positioned between the return electrode and the tissue structure and the electrically conductive fluid completes a conduction path between the active electrode and the return electrode.

9. The instrument of claim 8 wherein the active and return electrodes are configured, upon the application of a sufficiently high frequency voltage therebetween, to vaporize the fluid in a thin layer over at least a portion of the active electrode and to induce the discharge of energy from the vapor layer.

14. The instrument of claim 8 further comprising an electrically insulating support member between the active electrodes and the return electrode, the support member comprising an inorganic material.

15. The instrument of claim 14 wherein the support member has an axial opening in communication with the aspiration lumen.

10. An electrosurgical instrument for treating tissue from a target site within or on a patient'"'"'s body comprising:

a shaft having proximal and distal end portions and a plurality of active electrodes on the distal end portion, the active electrodes together forming a substantially planar tissue treatment surface;

a return electrode on the shaft spaced from the active electrodes;

an aspiration lumen within the shaft having a distal opening at the distal end portion of the shaft; and

wherein the active electrodes extend across a portion of the distal opening of the aspiration lumen to inhibit clogging of the aspiration lumen.

11. The instrument of claim 10 wherein the active electrodes each comprise a peripheral surface facing a direction substantially perpendicular to the planar tissue treatment surface, wherein the active electrodes are configured to ablate tissue adjacent to the tissue treatment surface and tissue adjacent to the peripheral surface.

12. The instrument of claim 11 wherein the peripheral surface extends 360 degrees around the active electrode.

13. The instrument of claim 10 wherein the active electrodes each comprise an L-shaped electrode having a first portion extending axially from the distal end portion of the shaft and a second portion contiguous with, and perpendicular to, the first portion, the second portion having a substantially planar surface opposite the shaft.

16. The instrument of claim 10 wherein the return electrode is spaced from the active electrodes such that, when the active electrodes are brought adjacent a tissue structure immersed in electrically conductive fluid, the active electrodes are positioned between the return electrode and the tissue structure and the electrically conductive fluid completes a conduction path between the active electrodes and the return electrode.

17. The instrument of claim 16 wherein the active and return electrodes are configured, upon the application of a sufficiently high frequency voltage therebetween, to vaporize the fluid in a thin layer over at least a portion of the active electrodes and to induce the discharge of energy from the vapor layer.