Methods for electrosurgical dermatological treatment

• US 6,210,402 B1
• Filed: 11/25/1997
• Issued: 04/03/2001
• Est. Priority Date: 11/22/1995
• Status: Expired due to Term

• Current Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Original Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Inventors: Eggers, Philip E., Thapliyal, Hira V., Brunell, Stephen M., Olsen, Phillip M.
• Primary Examiner(s): COHEN, LEE S
• Application Number:
  US08/977,845
• Time in Patent Office: 1,225 Days
• Field of Search: 606/32, 606/34, 606/41, 606/45, 606/48-50, 604/114, 607/99
• US Class Current: 606/32
• CPC Class Codes: A61B 18/042 using additional gas becoming plasma
• 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 2017/00026 Conductivity or impedance, e.g. of tissue
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61B 2017/00097 one of the thermometric elements being an electrode or the heating element
• 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 2017/00292 mounted on or guided by flexible, e.g. catheter-like, means
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2017/22001 Angioplasty, e.g. PCTA
• CPC Class Codes: A61B 2017/22038 with a guide wire
• 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 2018/00148 : with metal
• 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 2018/00196 : reciprocating lengthwise
• CPC Class Codes: A61B 2018/00327 : Ear, nose or throat
• CPC Class Codes: A61B 2018/00392 : Transmyocardial revascularisation
• CPC Class Codes: A61B 2018/00404 : Blood vessels other than those in or around the heart
• CPC Class Codes: A61B 2018/0047 : Upper parts of the skin, e.g. skin peeling or treatment of wrinkles
• CPC Class Codes: A61B 2018/00476 : Hair follicles
• 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 2018/00601 : Cutting
• CPC Class Codes: A61B 2018/00625 : Vaporization
• CPC Class Codes: A61B 2018/00642 : with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/0066 : without feedback, i.e. open loop control
• 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 2018/00761 : Duration
• CPC Class Codes: A61B 2018/00791 : Temperature
• CPC Class Codes: A61B 2018/00797 : measured by multiple temperature sensors
• CPC Class Codes: A61B 2018/00815 : measured by a thermistor
• CPC Class Codes: A61B 2018/00821 : measured by a thermocouple
• CPC Class Codes: A61B 2018/00827 : Current
• CPC Class Codes: A61B 2018/00875 : Resistance or impedance
• CPC Class Codes: A61B 2018/00886 : Duration
• 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 2018/1407 : Loop
• 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 2090/378 : using ultrasound
• CPC Class Codes: A61B 2218/002 : Irrigation
• CPC Class Codes: A61B 2218/007 : Aspiration
• CPC Class Codes: A61F 2/2493 : Transmyocardial revascularisation [TMR] devices
• CPC Class Codes: A61M 25/0133 : Tip steering devices
• CPC Class Codes: A61M 25/0147 : with movable mechanical means, e.g. pull wires
• 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

Abstract

Systems and methods are provided for selectively applying electrical energy to a target location on an external body surface, such as skin tissue removal and/or collagen shrinkage in the epidermis or dermis, e.g., the removal of pigmentations, vascular lesions (e.g., leg veins), scars, tattoos, etc., and for other surgical procedures on the skin, such as tissue rejuvenation, cosmetic surgery, wrinkle removal, hair removal and/or transplant procedures. The present invention applies high frequency (RF) electrical energy to one or more electrode terminals adjacent an external body surface, such as the outer surface of the skin, to remove and/or modify the structure of tissue structures within the skin. Depending on the specific cosmetic procedure, the present invention may be used to: (1) volumetrically remove tissue or hair (i.e., ablate or effect molecular dissociation of the tissue structure); (2) separate a tissue layer from an underlying tissue layer so that the tissue layer can be removed; (3) shrink or contract collagen connective tissue; and/or (4) coagulate blood vessels underlying the surface of the skin.

Claims

1. A method for dermatological treatment of an external body surface at a target site comprising:

providing an elongate electrode terminal with a longitudinal axis;

positioning the elongate electrode terminal in close proximity to a target site on an external body surface of the patient such that the longitudinal axis of the electrode terminal is substantially parallel to the external body surface of the patient; and

applying high frequency electrical energy to the electrode terminal; and

during the applying step, moving the electrode terminal across the external body surface in a direction transverse to the longitudinal axis of the electrode terminal to apply energy to the external body surface.

2. The method of claim 1 wherein the electrode terminal is traversed across the external body surface in a direction substantially perpendicular to the longitudinal axis of the electrode terminal to uniformly apply energy to the external body surface.

3. The method of claim 1 wherein the high frequency electrical energy is sufficient to effect contraction of collagen fibers within tissue at the target site.

4. The method of claim 3 wherein the external body surface comprises a tissue structure in the papillary dermis or the epidermis.

5. The method of claim 3 wherein the collagen fibers are heated to a temperature in the range of about 45°

C. to 90°

C.

6. The method of claim 1 further comprising delivering electrically conducting fluid to the target site, and contacting the electrically conducting fluid with a return electrode to provide a current flow path from the electrode terminal, through the electrically conducting fluid, and to the return electrode.

7. The method of claim 1 further comprising locating an electrically conducting gel on the external body surface to provide a current flow path from the electrode terminal, through the electrically conducting gel, and to a return electrode.

8. The method of claim 6 further comprising positioning the return electrode proximal to the electrode terminal to induce current flow from the electrode terminal away from the target site.

9. The method of claim 6 further comprising directing the electrically conducting fluid along a fluid path past the electrode terminal and the return electrode to generate the current flow path between the return electrode and the electrode terminal.

10. The method of claim 1 wherein the electrode terminal comprises an electrode array including a plurality of electrically isolated electrode terminals.

11. The method of claim 1 wherein the depth of tissue heating is less than about 2 mm.

12. The method of claim 1 further comprising removing a layer of the epidermis at the target site.

13. The method of claim 12 wherein the removing step comprises applying sufficient high frequency voltage to the electrode terminal to decouple the epidermis layer from the underlying tissue, and removing the decoupled epidermis layer from the underlying tissue.

14. The method of claim 12 wherein the removing step comprises applying sufficient high frequency voltage to the electrode terminal to remove the epidermis layer through molecular dissociation or disintegration.

15. The method of claim 1 wherein the external body surface is a region of scalp tissue, the method further comprising applying sufficient high frequency voltage to the electrode terminal to remove a hair shaft from the scalp tissue.

16. A method for dermatological treatment of an external body surface comprising:

positioning an electrode terminal in close proximity to a target site on the epidermis of the patient;

applying sufficient high frequency voltage to the electrode terminal to decouple a layer of the epidermis from the underlying tissue;

applying thermal energy to a tissue layer underlying the epidermis layer such that the tissue layer is heated to a temperature in the range of about 45°

to 90°

C.; and

removing the decoupled epidermis layer from the underlying tissue.

17. The method of claim 16 wherein the epidermis is decoupled from the papillary dermis, and said tissue layer is the papillary dermis.

18. The method of claim 16 wherein the decoupled epidermis layer is brushed away from the treatment site.

19. The method of claim 16 wherein the decoupled epidermis layer is flushed away from the treatment site.

20. The method of claim 16 wherein the electrode terminal comprises an elongate active electrode, the method further comprising:

providing the elongate active electrode with a longitudinal axis; and

positioning the elongate active electrode in close proximity to epidermis such that the longitudinal axis of the active electrode is substantially parallel to the epidermis.

21. The method of claim 20 further comprising traversing the active electrode across the epidermis in a direction substantially perpendicular to the longitudinal axis of the active electrode.

22. The method of claim 16 further comprising delivering electrically conducting fluid to the target site, and contacting the electrically conducting fluid with the electrode terminal and a return electrode to provide a current flow path from the electrode terminal, through the electrically conducting fluid, and to the return electrode.

23. The method of claim 22 further comprising directing the electrically conducting fluid along a fluid path past the electrode terminal and the return electrode to generate the current flow path between the return electrode and the electrode terminal.

24. The method of claim 16 further comprising locating an electrically conductive gel on the epidermis to provide a current flow path from the electrode terminal, through the conductive gel, and to a return electrode.

25. The method of claim 16 further comprising positioning a return electrode proximal to the electrode terminal to induce current flow from the electrode terminal away from the epidermis.

36. The method of claim 25 wherein the removing step comprises applying sufficient high frequency voltage to the active electrode to decouple the epidermis layer from the underlying tissue, and removing the decoupled epidermis layer from the underlying tissue.

37. The method of claim 25 wherein the removing step comprises applying sufficient high frequency voltage to the active electrode to ablate the epidermis layer.

26. A method for cosmetic treatment of an external body surface at a target site comprising:

providing an elongate active electrode with a longitudinal axis;

positioning the elongate active electrode in close proximity to a target site on an external body surface of the patient such that the longitudinal axis of the active electrode is substantially parallel to the external body surface of the patient;

applying high frequency voltage between the active electrode and a return electrode to apply energy to the external body surface; and

delivering electrically conductive fluid to the target site, and contacting the electrically conductive fluid with the active and return electrodes to provide a current flow path from the active electrode, through the electrically conductive fluid, and to the return electrode.

27. The method of claim 26 further comprising traversing the active electrode across the external body surface in a direction substantially perpendicular to the longitudinal axis of the active electrode.

28. The method of claim 26 wherein the high frequency voltage is sufficient to effect contraction of collagen fibers within tissue at the target site.

29. The method of claim 28 wherein the collagen fibers are heated to a temperature in the range of about 45°

C. to 90°

C.

30. The method of claim 26 wherein the external body surface comprises a tissue structure in the papillary dermis or the epidermis.

31. The method of claim 26 further comprising positioning the return electrode proximal to the active electrode to induce current flow from the active electrode away from the target site.

32. The method of claim 26 further comprising directing the electrically conductive fluid along a fluid path past the active electrode and the return electrode to generate the current flow path between the return electrode and the active electrode.

33. The method of claim 26 wherein the active electrode comprises an electrode array including a plurality of electrically isolated active electrodes.

34. The method of claim 26 wherein the depth of tissue heating is less than about 2 mm.

35. The method of claim 26 further comprising removing a layer of the epidermis at the target site.

38. A method for cosmetic treatment of an external body surface at a target site comprising:

providing an elongate active electrode with a longitudinal axis;

positioning a return electrode proximal to the active electrode to induce current flow from the active electrode away from the target site;

positioning the elongate active electrode in close proximity to a target site on an external body surface of the patient such that the longitudinal axis of the active electrode is substantially parallel to the external body surface of the patient; and

applying high frequency voltage between the active electrode and the return electrode to apply energy to the external body surface.

39. The method of claim 38 further comprising traversing the active electrode across the external body surface in a direction substantially perpendicular to the longitudinal axis of the active electrode.

40. The method of claim 38 wherein the high frequency voltage is sufficient to effect contraction of collagen fibers within tissue at the target site.

41. The method of claim 40 wherein the collagen fibers are heated to a temperature in the range of about 45°

C. to 90°

C.

42. The method of claim 38 wherein the external body surface comprises a tissue structure in the papillary dermis or the epidermis.

43. The method of claim 38 further comprising delivering electrically conductive fluid to the target site, and contacting the electrically conductive fluid with the active and return electrodes to provide a current flow path from the active electrode, through the electrically conductive fluid, and to the return electrode.

44. The method of claim 43 further comprising directing the electrically conductive fluid along a fluid path past the active electrode and the return electrode to generate the current flow path between the return electrode and the active electrode.

45. The method of claim 38 further comprising locating an electrically conducting gel on the external body surface to provide a current flow path from the active electrode, through the electrically conducting gel, and to the return electrode.

46. The method of claim 38 wherein the active electrode comprises an electrode array including a plurality of electrically isolated active electrodes.

47. The method of claim 38 further comprising removing a layer of the epidermis at the target site.

48. The method of claim 47 wherein the removing step comprises applying sufficient high frequency voltage to the active electrode to decouple the epidermis layer from the underlying tissue, and removing the decoupled epidermis layer from the underlying tissue.

49. The method of claim 47 wherein the removing step comprises applying sufficient high frequency voltage to the active electrode to ablate the epidermis layer.