Electrosurgical apparatus for resecting abnormal protruding growth

• US 5,078,716 A
• Filed: 05/11/1990
• Issued: 01/07/1992
• Est. Priority Date: 05/11/1990
• Status: Expired due to Term

• Current Assignee: Coopersurgical Incorporated (The Cooper Cos., Inc.)
• Original Assignee: Meditron Devices, Inc. (Boston Scientific Corporation)
• Inventors: Doll, Larry F.
• Primary Examiner(s): Cohen, Lee S.
• Application Number:
  US07/522,264
• Time in Patent Office: 606 Days
• Field of Search: 606/47, 606/48, 606/50
• US Class Current: 606/47
• CPC Class Codes: A61B 17/32056 Surgical snare instruments for removing or smashing calculi A61B2017/2212; tonsillotomes A61B17/26
• CPC Class Codes: A61B 18/14 Probes or electrodes 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 2018/00083 low, i.e. electrically insulating
• CPC Class Codes: A61B 2018/126 bipolar
• CPC Class Codes: A61B 2018/141 Snare

Abstract

The present invention relates to surgical instruments for removing protruding tissue such as tonsils, warts, polyps and like, from the body, more specifically, it relates to loop type snare instruments supplying a high frequency electrical current for coagulation and cutting during the removal of these body growths.

In a primary embodiment of the invention, a loop is provided which is made of electrically conductive wire connected to a loop made of electrically conductive wire within a tubular insulated sheath. The wire is connected to a handle assembly that will allow the loop to be extended from or retracted into the distal end of the tubular insulated sheath. The loop is covered over a major portion of its circumference by an insulating material, leaving only a minor portion of its circumference uninsulated at the portion of the loop most distal from the tubular sheath, and electrically active. The handle mechanism includes an electrical connector for connection of the conductive wire to an electrosurgical generator.

Claims

1. An electrosurgical apparatus for resecting abnormal protruding growths comprising

an elongated tubular electrically insulating sheath member having a proximal and a distal end,

a pair of elongated flexible electrically conductive wires with said wires disposed within said sheath and having a length greater than said sheath such that said wires each extend from both said proximal and said distal ends of said sheath with said wires each having proximal and distal ends,

electrically insulating connector means disposed at said distal ends of said wires for the purpose of mechanically connecting said distal ends of said wires to form a loop projecting from said distal end of said sheath and with said wires electrically insulated from each other and with said loop having a proximal and a distal portion,

electrical insulation means disposed covering all but a selected portion of each of said elongated wires which forms said loop, where said electrical insulation means covers the distal end of one of said wires,

handle means for sliding said wires relative to said sheath to expand or contract said loop,

electrical connection means for connecting said proximal ends of said wires to a bipolar electrosurgical current source means.

2. An electrosurgical apparatus according to claim 1 in which said electrical insulation means comprises

a distal electrical insulator segment covering a portion of one of said wires adjacent to said electrically insulating connector means and another electrical insulator segment spaced from said distal electrical insulator segment on said wire.

3. An electrosurgical apparatus according to claim 2 in which said distal electrical insulator segment is in the order of one hundred thousandths of an inch long.

4. An electrosurgical apparatus according to claim 2 in which said distal electrical insulator segment is in the range of ten thousandths to two hundred thousandths of an inch long.

5. An electrosurgical apparatus according to claim 2 further comprising a pair of bare wire portions formed by said electrical insulation means and formed, one each, on said pair of elongated wires and disposed at said distal ends of said wires and with said bare wire portions offset relative to each other.

6. An electrosurgical apparatus according to claim 5 in which said bare wire portions are offset relative to each other by an amount substantially equal to said distal electrical insulator segment which is disposed on one of said wires adjacent to said electrically insulating connector means.

7. An electrosurgical apparatus according to claim 2 in which said distal electrical insulator segment has a preferred range of fifty thousandths to two-hundred thousandths of an inch long.

8. An electrosurgical apparatus according to claim 1 in which said electrical insulation means is non-symmetrically located on said loop formed by said wires.

9. An electrosurgical apparatus according to claim 1 in which said selected portion of said loop comprises the distal portion of said loop.

10. An electrosurgical apparatus according to claim 1 in which said selected portion of said loop comprises a portion which is the order of 25% of the circumference of said loop.

11. An electrosurgical apparatus according to claim 1 in which said selected portion of said loop comprises a portion which is in the range of 10 to 40% of the circumference of said loop.

12. An electrosurgical apparatus according to claim 1 in which each of said wires has a diameter in the order of fifteenthousandths of an inch.

13. An electrosurgical apparatus according to claim 1 in which each of said wires is a multi-strand wire.

14. An electrosurgical apparatus according to claim 1 in which each of said wires has a preferred diameter in the range of ten to twenty thousandths of an inch.

15. An electrosurgical apparatus according to claim 1 in which each of said wires is made of stainless steel.

16. An electrosurgical apparatus according to claim 1 in which said loop is pre-bent to form an oval configuration.

17. An electrosurgical apparatus according to claim 1 in which said loop is pre-bent to form a hexagonally shaped configuration.

18. An electrosurgical apparatus according to claim 1 in which said loop is pre-bent to form a crescent shaped configuration.

19. An electrosurgical apparatus according to claim 1 further comprising

actuator means mounted on said proximal end of said sheath for endoscopic insertion of said distal end of said sheath into a patient'"'"'s body.

20. An electrosurgical apparatus according to claim 1 in which said wires are further defined as a first wire and a second wire with said insulation removed from a selected portion of said first wire which forms said loop and from a selected portion of said second wire which forms said loop and with said selected portion of said second wire of a length having a range from about 20% to about 250% of the length of said selected portion of said first wire.

21. An electrosurgical apparatus according to claim 1 in which said wires are further defined as a first wire and a second wire with said insulation removed from a selected portion of said first wire which forms said loop and from a selected portion of said second wire which forms said loop and with said selected portion of said second wire of a length having a range from less than the length of the selected portion of the first wire to a length greater than the length of the related portion of the first wire.