Microwave hyperthermia applicator with variable radiation pattern

• US 4,589,424 A
• Filed: 08/22/1983
• Issued: 05/20/1986
• Est. Priority Date: 08/22/1983
• Status: Expired due to Fees

• Current Assignee: Varian Associates Palo Alto CA
• Original Assignee: Varian Associates, Inc.
• Inventors: Vaguine, Victor A.
• Primary Examiner(s): Cohen, Lee S.
• Application Number:
  US06/525,182
• Time in Patent Office: 1,002 Days
• Field of Search: 128/804, 128/802, 128/399, 128/401, 219/10.55 R, 219/10.55 A, 219/10.55 F
• US Class Current: 607/154
• CPC Class Codes: A61N 5/02 using microwaves

Abstract

A direct contact microwave hyperthermia applicator includes a plurality of rectangular waveguide sections each having a radiating aperture. The waveguide sections are mounted with their long sides abutting. A pair of shutter elements for individually varying the radiating aperture is associated with each of the waveguide sections. The shutters can be adjusted to form a desired composite aperture which produces a radiation pattern adapted for efficient hyperthermia treatment of a tumor having a prescribed size, shape and location. Microwave power supplied to the radiating elements can be varied in phase and power level to further control the radiation pattern.

Claims

1. An applicator for hyperthermia treatment of tissue by irradiation with microwave energy comprising:

a plurality of side-by-side rectangular waveguides each having an open end forming a radiation aperture, whereby apertures of said plurality of waveguides provide a composite radiation aperture;

variable shutter means associated with each of said radiation apertues for individually varying said radiation apertures and forming a desired shape for said composite aperture, said shutter means comprising two shutter elements associated with each of said apertures and slidable across each said aperture, the two shutters for individual ones of said apertures being moveable toward and away from each other, the shutters for adjacent ones of said apertures being moveable along paths which are parallel one to the other; and

means for coupling each of said waveguides to a microwave power source,

whereby said shutter means can be adjusted to provide a radiation pattern adapted for efficient hyperthermia treatment of tissue having a prescribed size, shape and location.

2. The applicator as defined in claim 1 wherein said waveguides are arranged with coplanar radiating apertures.

3. The applicator as defined in claim 1 wherein each of said waveguides are elongated in cross-section and are arranged so that the longer sides thereof are side-by-side.

4. The applicator as defined in claim 1 wherein each of said waveguides is at least partially filled with dielectric material to permit operation at lower frequencies.