Method of treatment using magnetic resonance and apparatus therefor

• US 20030195410A1
• Filed: 04/14/2003
• Published: 10/16/2003
• Est. Priority Date: 08/10/1995
• Status: Abandoned Application

• Current Assignee: James Winter
• Original Assignee: James Winter
• Inventors: Winter, James
• Application Number:
  US10/412,913
• Publication Number:
  US 20030195410A1
• Time in Patent Office: Days
• US Class Current: 600/410
• CPC Class Codes: A61N 2/00 Magnetotherapy
• CPC Class Codes: A61N 2/02 using magnetic fields produced by coils, including single turn loops or electromagnets A61N2/12 takes precedence

Abstract

Treatment of malignant tumors or other lesions by localized transfer of radio frequency electromagnetic energy into a portion of the body may be achieved by means of spatially localized magnetic resonance (MR). A magnetic field with appropriate spatial distribution and radio frequency tuned to the resonant frequency unique to the tumor treatment volume will cause selective therapeutic energy deposition or heating within the tumor (hyperthermia). The desired magnetic field distribution for the MR treatment volume may be achieved by means of a main static magnetic field with a superimposed magnetic field to define the treatment volume size and shape, positioned by a gradient magnetic field. Treatment may be enhanced by MR contrast agents (such as gadolinium) and pharmacologic agents. The therapy may be achieved by simultaneous resonance throughout an entire selected therapy volume, or successively point by point, or by superimposition of small volumes, including by successively excited points, lines or planes as practiced in prior art magnetic resonance imaging systems, facilitating simultaneous imaging and therapy. In a preferred embodiment, the invention is incorporated in a magnetic resonance imaging (MRI) scanner wherein the imager modified by the addition of a localizing magnet is used visually or by automated or semi-automated computer image processing to define and localize the treatment volume and the main magnetic field and positioning gradient fields are created by the same magnets used for imaging and the radio frequency apparatus used for Magnetic Resonance Therapy uses the same electronics and probe coil used for MRI.

Claims

1. A magnetic resonance therapy apparatus for delivering therapy to a predetermined non-planar volume of tissue comprising:

a. a main magnet;

b. three orthogonal gradient coils;

C. a localizing magnetic field shaping apparatus;

d. a radio frequency transmitter; and

e. probe coils.

2. A method of delivering energy to tissues in sufficient amount to heat the tissues to cause a therapeutic effect comprising the steps of:

a. locating the tissues in a magnetic resonance therapy apparatus comprising;

(1) a main magnet;

(2) three orthogonal gradient coils;

(3) a localizing magnetic field shaping apparatus;

(4) a radio frequency transmitter;

(5) probe coils; and

(6) a radio frequency receiver;

b. varying the field strength of the magnetic fields to create a magnetic field of desired strength throughout the tissue;

c. applying radio frequency energy of the correct frequency to cause magnetic resonance to occur within the volume of tissue subject to the determined magnetic field; and

d. maintaining the radio frequency energy until sufficient energy has been delivered to the tissue to create a desired temperature rise and therapeutic effect.