Electrosurgical electrode for skin grafting

• US 5,683,387 A
• Filed: 01/29/1996
• Issued: 11/04/1997
• Est. Priority Date: 01/29/1996
• Status: Expired due to Fees

• Current Assignee: Ellman International, Inc. (Hologic Incorporated)
• Original Assignee: ALAN G. ELLMAN, Jon C. Garito
• Inventors: Garito, Jon C., Ellman, Alan G.
• Primary Examiner(s): Cohen, Lee S.
• Application Number:
  US08/593,010
• Time in Patent Office: 645 Days
• Field of Search: 606/41, 606/45, 606/49
• US Class Current: 606/45
• CPC Class Codes: A61B 17/322 Skin grafting apparatus
• CPC Class Codes: A61B 18/10 Power sources therefor
• 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 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/1253 monopolar

Abstract

An electrode for use in an electrosurgical skin grafting procedure. In a preferred embodiment, the electrode is uniquely configured to form a U-support terminating in an active wire, generally U-shaped, whose width controls the width of the graft, and the length of whose arms controls the thickness of the graft. The active wire is supported by structure that is completely electrically-insulated to ensure excision only of the desired tissue while avoiding damage to surrounding tissue. The tissue incising is effected with the bare active wire at a depth stopped by a shoulder between the bare wire arms and the adjacent portions of the electrode support.

Claims

1. An electrosurgical electrode for excising a thin slice of skin tissue for skin grafting, comprising:

(a) an electrically-conductive shaft member having a first end for mounting to a handpiece and a second end,

(b) said second end comprising an active, electrically-conductive, wire portion having a generally U-shape formed by exposed arm portions extending in a longitudinal direction and on opposite sides of an exposed bight portion extending substantially transversely to the longitudinal direction, said bight portion being straight or slightly bowed,

(c) said active wire portion being exposed electrically for applying electrosurgical currents to said tissue when said shaft member is connected to a source of electrosurgical currents,

(d) said shaft member having portions adjacent said exposed arm portions, said shaft portions being electrically-insulating to prevent contact and passage of electrosurgical currents to areas adjacent to or surrounding the tissue to be excised, said active wire portion being configured such that the thickness and width of the skin tissue slice excised is determined by the length in the longitudinal direction of the exposed arm portions and the length of the exposed bight portion extending substantially transversely thereto.

2. An electrosurgical electrode as claimed in claim 1, wherein the arm portions of said active wire portion having a length in the longitudinal direction not exceeding about 3 mm.

3. An electrosurgical electrode as claimed in claim 1, wherein said second end of said shaft member comprises a generally electrically-insulating U-support comprising a bight portion and two arm portions each connected to one of the arm portions of the active wire portion.

4. An electrosurgical electrode as claimed in claim 3, wherein the two arm portions of said electrically-insulating U-support adjacent the arm portions of said active wire portion have a larger diameter than that of said arm portions of said active wire portion forming with each of the latter a shoulder acting as a stop preventing tissue penetration of the active wire portion beyond the length of its arm portions.

5. An electrosurgical electrode as claimed in claim 4, wherein the bight portion of the active wire portion has a length transverse to the longitudinal direction between about 8-12 mm.

6. An electrosurgical electrode as claimed in claim 5, wherein the bight portion of the active wire portion is straight.

7. An electrosurgical electrode as claimed in claim 5, wherein the bight portion of the active wire portion is slightly concave viewed from the shaft member.

8. An electrosurgical electrode as claimed in claim 5, wherein the bight portion of the active wire portion is constituted of a thin wire having a diameter of about 0.004 inches.

9. An electrosurgical electrode as claimed in claim 3, wherein the active wire portion and the electrically-insulating U-support form a generally rectangular open loop.

10. The electrosurgical electrode as claimed in claim 1, wherein the active wire portion is made of tungsten.

11. The electrosurgical electrode as claimed in claim 10, wherein the active wire portion of tungsten has a diameter of about 0.004 inches.

12. The electrosurgical electrode as claimed in claim 1, wherein the arm portions of the active wire portion have a length of 1-3 mm.

13. In combination:

electrosurgical apparatus capable of supplying high frequency currents,

a handpiece having means at one end for connection to the electrosurgical apparatus and having at its opposite end means for mounting the electrically-conductive shaft member of an electrosurgical electrode and for supplying the high frequency currents to said electrode;

an electrosurgical electrode for excising a thin slice of skin tissue for skin grafting, comprising;

(a) an electrically-conductive shaft member having a first end for mounting to the handpiece and a second end,

(b) said second end comprising an active, electrically-conductive, wire portion having a generally U-shape formed by exposed arm portions extending in a longitudinal direction and on opposite sides of an exposed bight portion extending substantially transversely to the longitudinal direction, said bight portion being straight or slightly bowed,

(c) said active wire portion being exposed electrically for applying electrosurgical currents to said tissue when said shaft member is connected to the electrosurgical apparatus,

(d) said shaft member having portions adjacent said exposed arm portions, said shaft portions being electrically-insulating to prevent contact and passage of electrosurgical currents to areas adjacent to or surrounding the tissue to be excised,

(e) means forming a shoulder where said exposed arm portions meet the adjacent portions of said shaft member, said shoulder being sufficiently wide to prevent tissue penetration of said active wire portion beyond its length in the longitudinal direction of the arm portions, said active wire portion being configured such that the thickness and width of the skin tissue slice excised is determined by the length in the longitudinal direction of the arm portions and the length of the bight portion extending between the arm portions.

14. The combination of claim 13, wherein the high frequency currents are at a frequency exceeding 2 Mhz.

15. A skin graft surgical procedure for excising tissue of a patient, comprising the steps:

(a) providing electrosurgical apparatus connected to a handpiece holding an electrosurgical electrode, said electrosurgical electrode comprising;

(i) an electrically-conductive shaft member having a longitudinal direction and a first end for mounting to the handpiece and a second end,

(ii) said second end comprising an active, electrically-conductive, wire portion having a generally U-shape formed by exposed arm portions on opposite sides of an exposed bight portion,

(iii) said active wire portion being exposed electrically for applying electrosurgical currents to said tissue when said shaft member is connected to the electrosurgical apparatus,

(iv) said shaft member having portions adjacent said exposed arm portions, said shaft member portions being electrically-insulating to prevent contact and passage of electrosurgical currents to areas adjacent to or surrounding the tissue to be excised,

(v) means forming a shoulder where said active wire portion meets the adjacent portions of said shaft member, said shoulder being sufficiently wide to prevent tissue penetration of said active wire portion beyond its length,

(b) applying the active wire portion of the electrode to a donor site of a patient for the graft and activating the electrosurgical apparatus,

(c) penetrating the tissue of the patient until stopped by the means forming a shoulder,

(d) excising a graft with the active wire portion of the electrode by moving the electrode through the tissue.

16. The skin graft surgical procedure of claim 15 wherein the electrosurgical currents are at a frequency exceeding 2 MHz.