Methods for targeted electrosurgery on contained herniated discs

• US 20020120259A1
• Filed: 12/20/2000
• Published: 08/29/2002
• Est. Priority Date: 06/07/1995
• Status: Active Grant

• Current Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Original Assignee: David C. Hovda, Jean Woloszko, John J. Lettice, Thomas Kula Jr
• Inventors: Woloszko, Jean, Hovda, David C., Kula, Thomas Jr., Lettice, John J.
• Granted Patent: US 7,179,255 B2
• Time in Patent Office: Days
• US Class Current: 606/32
• CPC Class Codes: A61B 1/3135 for examination of the epidural or the spinal space
• CPC Class Codes: A61B 18/042 using additional gas becoming plasma
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 18/1477 Needle-like probes
• 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 2017/00261 Discectomy
• CPC Class Codes: A61B 2017/00274 Prostate operation, e.g. prostatectomy, turp, bhp treatment
• 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 2018/00434 : Neural system
• CPC Class Codes: A61B 2018/0044 : Spinal cord
• CPC Class Codes: A61B 2018/00505 : Urinary tract
• CPC Class Codes: A61B 2018/00547 : Prostate
• 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 2018/00589 : Coagulation
• CPC Class Codes: A61B 2018/00678 : upper
• CPC Class Codes: A61B 2018/00702 : Power or energy
• CPC Class Codes: A61B 2018/00726 : Duty cycle
• 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 2018/1425 : Needle
• 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: A61B 90/11 : with guides for needles or instruments, e.g. arcuate slides or ball joints
• CPC Class Codes: A61F 2/2493 : Transmyocardial revascularisation [TMR] devices

Abstract

Apparatus and methods for treating an intervertebral disc by ablation of disc tissue. A method of the invention includes positioning at least one active electrode within the intervertebral disc, and applying at least a first high frequency voltage between the active electrode(s) and one or more return electrode(s), wherein the volume of the nucleus pulposus is decreased, pressure exerted by the nucleus pulposus on the annulus fibrosus is reduced, and discogenic pain of a patient is alleviated. In other embodiments, a curved or steerable probe is guided to a specific target site within a disc to be treated, and the disc tissue at the target site is ablated by application of at least a first high frequency voltage between the active electrode(s) and one or more return electrode(s). A method of making an electrosurgical probe is also disclosed.

Claims

1. A method of using an electrosurgical system for treatment of a contained herniation of an intervertebral disc of a patient, the electrosurgical system including a power supply unit functionally coupled to at least one active electrode, the at least one active electrode disposed on a shaft distal end of an electrosurgical probe, and the method comprising:

a) guiding the shaft distal end within the intervertebral disc such that the at least one active electrode is in the vicinity of the contained herniation; and

b) applying a high frequency voltage between the at least one active electrode and at least one return electrode, wherein at least a portion of tissue in the vicinity of the contained herniation is ablated.

2. The method of claim 1, further comprising, before said step a):

c) advancing an introducer needle towards the intervertebral disc, the introducer needle including a lumen and a needle distal end;

d) passing the shaft distal end through the lumen distally beyond the needle distal end, wherein the at least one active electrode avoids contact with the needle distal end; and

e) retracting the shaft distal end into the lumen of the introducer needle, wherein the at least one active electrode avoids contact with the needle distal end.

3. The method of claim 1, wherein the at least one return electrode is located on the shaft or on a dispersive pad.

4. The method of claim 1, wherein the contained herniation comprises a bulge in a nucleus pulposus of the disc and the bulge in the nucleus pulposus is contained within an annulus fibrosus of the disc.

5. The method of claim 1 , wherein said step b) results in molecular dissociation of disc tissue in the vicinity of the contained herniation, and the volume of the nucleus pulposus is decreased.

6. The method of claim 2, wherein the guiding step is performed after the shaft distal end has been extended distally beyond the needle distal end.

7. The method of claim 1, wherein the guiding step comprises rotating the shaft about its longitudinal axis.

8. The method of claim 7, wherein the guiding step further comprises axial translation of the shaft.

9. The method of claim 1, wherein the shaft has a pre-defined curvature both prior to and after said guiding step.

10. The method of claim 1, wherein the method is performed percutaneously.

11. The method of claim 1, wherein said step a) is performed under fluoroscopy, and the position of the shaft distal end relative to the contained herniation is visualized fluoroscopically.

12. The method of claim 11, wherein the shaft includes a radiopaque tracking device on the shaft distal end, or at least one radiopaque depth marking.

13. The method of claim 9, wherein the pre-defined curvature comprises a first curve and a second curve proximal to the first curve, and the first curve and the second curve are in the same plane relative to the longitudinal axis of the shaft.

14. The method of claim 13, wherein the first curve is characterized by a first angle and the second curve is characterized by a second angle, wherein the first angle is in the range of from about 2°

to about 8°

, and the second angle is in the range of from about 4°

to about 18°

.

15. The method of claim 1, wherein the at least one active electrode comprises an electrode head having a substantially apical spike and a substantially equatorial cusp, and the apical spike and the equatorial cusp provide a high current density in the vicinity of the electrode head upon application of the high frequency voltage between the at least one active electrode and the return electrode, the high current density promotes formation of a plasma in the vicinity of the electrode head, and the plasma causes localized ablation of disc tissue at a temperature in the range of from about 45°

C. to about 90°

C.

16. The method of claim 1, wherein the disc comprises a fragment of nucleus pulposus.

17. The method of claim 1, wherein the method is performed in conjunction with epidural injection of a steroid.

19. The method of claim 18, wherein the target site comprises a bulge in a nucleus pulposus, the bulge in the nucleus pulposus is contained within an annulus fibrosus, and the method further comprises:

e) guiding the shaft distal end portion to the bulge in the nucleus pulposus.

20. The method of claim 19, wherein the shaft distal end portion has a pre-defined curvature, and said step e) comprises:

f) during said step c), rotating the shaft about its longitudinal axis.

21. The method of claim 18, wherein the method is performed percutaneously under fluoroscopy, and the position of the shaft distal end portion relative to the target site is visualized fluoroscopically.

22. The method of claim 18, wherein said step d) results in ablation of disc tissue, the volume or the mass of the disc tissue is decreased, and discogenic pain is alleviated.

23. The method of claim 18, wherein said step d) comprises applying a high frequency voltage in the range of from about 150 volts rms to about 350 volts rms between the at least one active electrode and the at least one return electrode, such that disc tissue at the target site is ablated at a temperature in the range of from about 45°

C. to about 90°

C.

24. The method of claim 18, further comprising:

h) applying a quantity of an electrically conductive fluid in the vicinity of the at least one active electrode.

25. The method of claim 18, wherein the shaft includes a first curve and a second curve proximal to the first curve, and the first curve and the second curve are in the same plane relative to the longitudinal axis of the shaft

26. The method of claim 18, wherein the at least one active electrode includes a filament, the shaft includes a first insulating sleeve encasing the filament, a return electrode on the first insulating sleeve, an insulating collar located at a distal end of the first insulating sleeve proximal to the return electrode, a second insulating sleeve on the return electrode, and a shield on the second insulating sleeve.

27. The method of claim 18, wherein the at least one active electrode comprises an electrode head having a substantially apical spike and a substantially equatorial cusp, and the apical spike and the equatorial cusp provide a high current density in the vicinity of the electrode head upon execution of said step d).

28. The method of claim 18, further comprising the step of:

l) injecting a steroid into an epidural space adjacent to the intervertebral disc.

18. A method of ablating tissue at a target site of an intervertebral disc having a contained herniation, the method comprising:

a) providing an electrosurgical system including a probe, an introducer needle, and a power supply unit coupled to the probe, the probe having a shaft, the shaft including a distal end portion having at least one active electrode, the introducer needle having a lumen for accommodating axial movement of the shaft therein;

b) advancing the introducer needle towards the intervertebral disc;

c) passing the shaft distal end portion distally through the lumen of the introducer needle towards the disc, wherein the shaft distal end portion is positioned in the vicinity of the contained herniation; and

d) applying a high frequency voltage between the at least one active electrode and at least one return electrode, the high frequency voltage selected for ablating disc tissue at the target site.