Local current capacitive field applicator for interstitial array

• US 4,712,559 A
• Filed: 09/20/1985
• Issued: 12/15/1987
• Est. Priority Date: 06/28/1985
• Status: Expired due to Fees

• Current Assignee: BSD Medical Corporation
• Original Assignee: BSD Medical Corporation
• Inventors: Turner, Paul F.
• Primary Examiner(s): Coven, Edward M.
• Application Number:
  US06/778,325
• Time in Patent Office: 816 Days
• Field of Search: 128/303.13, 128/399, 128/401, 128/422, 128/784, 128/786, 128/804
• US Class Current: 607/99
• CPC Class Codes: A61N 5/02 using microwaves
• CPC Class Codes: H01Q 13/08 Radiating ends of two-conductor microwave transmission lines, e.g. of coaxial lines, of microstrip lines

Abstract

An electromagnetic hyperthermia system for heating local regions of body tissue wherein the system includes a source of electromagnetic radiation connected to a power divider for distributing radiation to several power control devices that control the electromagnetic radiation transmission. Each of the power cotrol devices is connected to several radiation applicators. The radiation applicators include the capability for capacitively coupling radiation into body tissue and further include a sensor that provides an indication of adjacent body tissue temperature. A data processor is connected to the source, the power control apparatus and the temperature sensors and control the amount of heat in accordance with a desired heating pattern.

Claims

1. An electromagnetic hyperthermia system for heating local regions of body tissue, said system comprising:

a source of electromagnetic energy;

a power divider connected to the source for distributing the electromagnetic energy, a plurality of power control means including at least an A channel and a B channel connected to the power divider for receiving the electromagnetic energy and controlling the electromagnetic energy conduction, a corresponding number of plurality of capacitive type applicators connected to the plurality of power control means, a plurality of tube means for insertion into the body tissue in or around a cancerous growth, each of said plurality of tube means adapted to receive an applicator of the corresponding number of plurality of capacitive type applicators, said plurality of capacitive type applicators being mounted in the plurality of tube means for acting as electrodes of which at least one electrode is connected to channel A and at least one electrode is connected to channel B for enabling current to flow between channel A and channel B through the tissue to be heated and said plurality of capacitive type applicators further including temperature sensing means for providing an indication of adjacent body tissue temperatures; and

a data processing means connected to the source, the plurality of power control means and the temperature sensing means for controlling the amount of heating in accordance with a desired heating pattern.

2. An electromagnetic hyperthermia system according to claim 1 wherein said plurality of power control means regulates the amplitude and phase of electromagnetic radiation transmitted to each applicator.

3. An electromagnetic hyperthermia system according to claim 1 wherein said power control means provides power to pairs of applicators in order to provide the capacitive coupling of electromagnetic radiation.

4. An electromagnetic hyperthermia system according to claim 1 wherein each tube means of the plurality of tube means is a dielectric tube.

5. An electromagnetic hyperthermia system according to claim 4 wherein each dielectric tube is a catheter.

6. An electromagnetic hyperthermia system according to claim 1 wherein each applicator of the plurality of applicators includes first and second lengths having dielectric sleeves of first and second diameters, and first and second metal sections mounted respectively within said first and second dielectric sleeves, said first and second metal sections including, respectively, a centrally disposed conductor and an elongated tip, the centrally disposed conductor having a diameter substantially smaller than the diameter of the elongated tip, whereby the capacitance at the elongated tip through the dielectric sleeve into the surrounding tissue is substantially greater than the capacitance at the centrally disposed conductor through the dielectric sleeve into the surrounding tissue for more selective heating of the surrounding tissue.