Methods for volumetric tissue ablation

• US 6,468,273 B1
• Filed: 02/09/2000
• Issued: 10/22/2002
• Est. Priority Date: 03/24/1995
• Status: Expired due to Term

• Current Assignee: Board of Regents of the University of Nebraska
• Original Assignee: Board of Regents of the University of Nebraska
• Inventors: Leveen, Robert F., Fox, Randy
• Primary Examiner(s): COHEN, LEE S
• Application Number:
  US09/500,732
• Time in Patent Office: 986 Days
• Field of Search: 606/41, 606/49, 606/50, 607/98, 607/99, 607/113, 607/116, 607/128
• US Class Current: 606/41
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• CPC Class Codes: A61B 18/1477 Needle-like probes
• CPC Class Codes: A61B 18/1485 having a short rigid shaft for accessing the inner body through natural openings
• 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 18/18 by applying electromagnetic radiation, e.g. microwaves radiation therapy A61N5/00
• CPC Class Codes: A61B 2018/00214 Expandable means emitting energy, e.g. by elements carried thereon
• CPC Class Codes: A61B 2018/1425 Needle
• CPC Class Codes: A61B 2018/143 multiple needles
• CPC Class Codes: A61B 2018/1432 curved
• CPC Class Codes: A61B 2018/1475 Electrodes retractable in or deployable from a housing
• CPC Class Codes: A61N 5/045 specially adapted for treatment inside the body

Abstract

A volumetric tissue ablation apparatus includes a probe having a plurality of wires journaled through a catheter with a proximal end connected to the active terminal of a generator and a distal end projecting from a distal end of the catheter. The probe wire distal ends are arranged in an array with the distal ends located generally radially and uniformly spaced-apart from the catheter distal end. A conductor connected to the return terminal of the generator is located relative to the probe wire array to form a closed electrical circuit through tissue to be ablated. Preferably, the probe wire array includes 10 wires, each formed in an arch from the catheter distal end. The conductor can be either a conventional ground plate upon which the tissue is supported, or a conductor wire extending through the probe and electrically insulated from the probe wires.

Claims

1. An improved method for the hyperthermic treatment of tumors in solid tissue, said method being of the type wherein an electrode is positioned in solid tissue at the tumor and wherein radio frequency current is delivered to the tissue to heat and necrose the tumor, wherein the improvement comprises delivering the radio frequency current from an electrode array under conditions which necrose the tumor without sparking or evident charring of the tissue.

2. An improved method as in claim 1, wherein the electrode array is configured to permit radio frequency to be delivered at 60 watts for 5 minutes without sparking or evident charring.