Loop electrodes for electrocautery probes for use with a resectoscope

• US 5,957,923 A
• Filed: 10/07/1996
• Issued: 09/28/1999
• Est. Priority Date: 04/20/1995
• Status: Expired due to Term

• Current Assignee: Symbiosis Corporation (Boston Scientific Corporation)
• Original Assignee: Symbiosis Corporation (Boston Scientific Corporation)
• Inventors: Hahnen, Kevin F., Beideman, Tracie L.
• Primary Examiner(s): COHEN, LEE S
• Application Number:
  US08/725,937
• Time in Patent Office: 1,086 Days
• Field of Search: 606/45, 606/46, 606/49
• US Class Current: 606/46
• 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 2018/00607 Coagulation and cutting with the same instrument

Abstract

An electrocautery probe includes a distal loop electrode mounted between a pair of arms which are joined at their proximal ends to an electrode lead, and a mounting sleeve for slideably coupling the probe to the guide tube of a resectoscope. The arms are skewed from a longitudinal axis defined by the electrode lead and are covered with an insulative material which extends to the distal end of the arms and terminates in a straight edge parallel to a plane substantially perpendicular to the arms. The loop electrode is angled approximately 25°-35° proximally relative to a plane substantially perpendicular to the electrode lead. The loop electrode further defines sharp upper distal and proximal edges. A cross-section of the electrode further defines an upper surface, a leading distal surface, a lower distal surface, a lower proximal surface.

Claims

1. A loop electrode for use in an electrocautery probe having two arms between which said electrode is mounted, said electrode comprising:

a substantially U-shaped conductive member angled proximally relative to a plane substantially perpendicular to a longitudinal axis of the electrocautery probe, the conductive member having a cross section defining a broad lower surface edge.

2. A loop electrode according to claim 1, wherein:

said cross section further defines an upper surface, a leading distal surface, a lower distal surface and a proximal surface.

3. A loop electrode according to claim 2, wherein:

said lower distal and proximal surfaces form a lower proximal edge having an obtuse angle, and said leading distal surface and said lower distal surface form a lower distal edge.

4. A loop electrode according to claim 3, wherein:

said lower distal edge has an angle of approximately 95°

-105°

, and said lower proximal edge has an angle of approximately 135°

-150°

.

5. A loop electrode according to claim 3, wherein:

said upper surface has a length of approximately 0.043-0.061 inches.

6. A loop electrode according to claim 5, wherein:

said leading distal surface extends approximately 0.018-0.022 inches between said upper surface and said lower distal surface, and said lower distal surface extends approximately 0.024-0.032 inches between said leading distal surface and said proximal surface.

7. A loop electrode according to claim 1, wherein:

said cross section defines a sharp upper distal edge and a sharp upper proximal edge.

8. A loop electrode according to claim 7, wherein:

said upper distal edge has an angle of approximately between 55°

-65°

, and said upper proximal edge has an angle of approximately 42°

-52°

.

9. A loop electrode according to claim 1, wherein:

said U-shaped conductive member has a height approximately 0.180-0.220 inches.

10. The loop electrode of claim 1, wherein the conductive member is angled approximately 25°

to 35°

proximally relative to the plane substantially perpendicular to the longitudinal axis.

11. An electrocautery probe for use with a resectoscope, comprising:

a) a pair of conductive arms having proximal and distal ends, said arms joined together at their proximal ends;

b) an electrode lead coupled to said proximal ends of said conductive arms and extending proximally therefrom, said electrode lead defining a longitudinal axis; and

c) a substantially U-shaped electrode angled proximally relative to a plane substantially perpendicular to the longitudinal axis, the electrode having two upper ends, each of which is coupled to a respective one of said distal ends of said pair of conductive arms, said electrode having a cross section which defines a broad flat lower surface and at least one edge.

12. An electrocautery probe according to claim 11, wherein:

said arms lie in a first plane which is skewed from said axis of said electrode lead.

13. An electrocautery probe according to claim 11, wherein:

said cross section further defines an upper surface, a leading distal surface, a lower distal surface and a proximal surface.

14. An electrocautery probe according to claim 13, wherein:

said lower distal and proximal surfaces form a lower proximal edge having an obtuse angle, and said leading distal surface and said lower distal surface form a lower distal edge.

15. An electrocautery probe according to claim 14, wherein:

said lower distal edge has an angle of approximately 95°

-105°

, and said lower proximal edge has an angle of approximately 135°

-150°

.

16. An electrocautery probe according to claim 14, wherein:

said upper surface has a length of approximately 0.043-0.061 inches.

17. An electrocautery probe according to claim 16, wherein:

said leading distal surface extends approximately 0.018-0.022 inches between said upper surface and said lower distal surface, and said lower distal surface extends approximately 0.024-0.032 inches between said leading distal surface and said proximal surface.

18. An electrocautery probe according to claim 11, wherein:

said cross section defines a sharp upper distal edge and a sharp upper proximal edge.

19. An electrocautery probe according to claim 18, wherein:

said upper distal edge has an angle of approximately between 55°

-65°

, and said upper proximal edge has an angle of approximately 42°

-52°

.

20. An electrocautery probe according to claim 11, further comprising:

d) an insulative sheath extending over said arms and terminating at said distal end of said arms in a straight edge substantially perpendicular to a plane formed by said arms.

21. An electrocautery probe according to claim 11, wherein:

said U-shaped member has a height approximately 0.180-0.220 inches.

22. An electrocautery probe according to claim 11, further comprising:

d) a mounting sleeve for slideably coupling said probe to the resectoscope, said mounting sleeve made of a material which reduces capacitive coupling.

23. The electrocautery probe of claim 11, wherein the U-shaped electrode is angled approximately 25°

to 35°

proximally relative to the plane substantially perpendicular to the longitudinal axis.