Method and apparatus for controlling and optimizing the heating pattern for a hyperthermia system

• US 4,397,314 A
• Filed: 08/03/1981
• Issued: 08/09/1983
• Est. Priority Date: 08/03/1981
• Status: Expired due to Fees

• Current Assignee: NationsBank of Texas NA (Bank of America Corp.)
• Original Assignee: Clini-Therm Corporation
• Inventors: Vaguine, Victor A.
• Primary Examiner(s): Apley, Richard J.
• Assistant Examiner(s): Yanulis, George
• Application Number:
  US06/289,127
• Time in Patent Office: 736 Days
• Field of Search: 128/399, 128/400, 128/401, 128/419 N, 128/422, 128/736, 128/783, 128/804
• US Class Current: 607/104
• CPC Class Codes: A61B 18/18 by applying electromagnetic radiation, e.g. microwaves radiation therapy A61N5/00
• CPC Class Codes: A61B 18/1815 using microwaves
• CPC Class Codes: A61N 5/02 using microwaves

Abstract

A hyperthermia treatment system has multiple applicators and multiple temperature sensors for controlling the operation of the hyperthermia system. A temperature sensor probe implanted within a tumor provides a temperature signal for controlling and optimizing the power input to multiple applicators to maintain the system output during the treatment period at a predetermined control temperature. Temperature sensors implanted in the region of the healthy tissue provide temperature signals to override the controls providing power input to the applicators to prevent injury to healthy tissues. Individual microwave applicators are evaluated during the hyperthermia treatment to determine their effect on the overall heating pattern for optimizing the heating pattern.

Claims

1. In a microwave hyperthermia treatment system including a microwave power generator, a plurality of microwave applicators powered by the microwave power generator, and a power input control for each of the applicators to vary the power input to the applicators from the microwave power generator, wherein the improvement comprises:

multiple temperature sensors for actively monitoring the temperatures in both the tumor and the region of normal tissue subject to treatment, including means for generating a temperature control signal for each of said sensors;

a first means for generating a control signal to selected ones of the power input controls of the microwave applicators in response to said temperature control signal from said sensors for the tumor for maintaining the temperature within the tumor at a predetermined control temperature;

a second means for generating a control signal to selected ones of the power input controls to the microwave applicators in response to a temperature control signal from said sensors in a region of normal tissue indicating a temperature in excess of a threshold temperature; and

means for said second control signal to override said first control signal to decrease the power input to selected ones of said applicators, whereby the normal tissue is protected by keeping it below a predetermined threshold temperature while maintaining the temperature within the tumor at the temperature closest to the predetermined control temperature permitted by the power input to the microwave applicators.

2. The hyperthermia treatment system of claim 1, wherein said multiple temperature sensors for monitoring the temperature within the region of normal tissue and the region of the tumor comprises:

a plurality of semiconductor temperature sensors spaced a predetermined distance apart to form a linear array, each of said temperature sensors being connected by a pair of fiber optic cables to determine the temperature at each of the points where the semiconductor temperature sensors are located.

4. The hyperthermia treatment system of claim 1 and further comprising:

means for cooling the surface of the treatment area; and

means for controlling said cooling means in response to temperature information signals from said multiple temperature sensor probes.

5. The hyperthermia treatment system of claim 1 and further comprising:

means for cooling the skin area of the patient treatment area, including means for controlling said cooling means;

at least one temperature sensor for monitoring the temperature of the surface skin area; and

means for regulating said cooling control means responsive to said skin temperature sensor.

8. The microwave hyperthermia treatment system of claim 1 and further comprising:

means for operator control of said power input control means, such that the operator observing said display means may make real time adjustments to said power input control means for said microwave hyperthermia applicator.

3. In a microwave hyperthermia treatment system including a microwave power generator, a plurality of microwave applicators powered by the microwave power generator, and a power input control for each of the applicators to vary the power input to the applicators from the microwave power generator, wherein the improvement comprises:

multiple temperature sensors for actively monitoring the temperatures in both the tumor and the region of normal tissue subject to treatment, including means for generating a temperature control signal for each of said sensors;

a first means for generating a control signal to the power input control to at least one of the microwave applicators in response to said temperature control signal from at least one of said sensors for the tumor for maintaining the temperature within the tumor at the predetermined control temperature;

a second means for generating a control signal to the power input control to at least one of the microwave applicators in response to a temperature control signal from at least one of said sensors in a region of normal tissue indicating a temperature in excess of a threshold temperature; and

means for said second control signal to override said first control signal to decrease the power input to an applicator, whereby the normal tissue is protected by keeping it below a predetermined threshold temperature, the multiple microwave applicators being geometrically configured to be proximal the surface of a human tissue closest to the tumor.

6. A hyperthermia treatment system including an ultrasonic generator, a plurality of ultrasonic applicators, and a power input control to each of the applicators, wherein the improvement comprises:

multiple temperature sensors for actively monitoring the temperatures in both the tumor and normal tissue in a patient treatment area including means for generating a temperature control signal for each of said sensors;

a first means for generating a control signal to selected ones of the power input controls of the ultrasonic applicators in response to said temperature control signals from said sensors for the tumor for maintaining the temperature within the tumor at a controlled treatment temperature;

a second means for generating a control signal to selected ones of the power input controls to the ultrasonic applicators in response to a temperature control signal from the sensors in a region of normal tissue indicating a temperature in excess of a predetermined threshold temperature; and

means for said second control signal to override said first control signal to decrease the power input to selected ones of said applicators, whereby the normal tissue is protected from overheating while maintaining the temperature within the tumor at the predetermined control treatment temperature.

7. A microwave hyperthermia treatment system, comprising:

a microwave power generator;

a plurality of microwave applicators connected to said microwave generator and distributed in a desired orientation;

means for individually controlling the power input from said microwave generator to each of said microwave applicators;

an electronic digital signal processing system, said system including an electronic digital signal processor, a data memory unit, a program memory unit, means for entering data to said data memory unit and a display means;

a plurality of nonperturbing temperature sensors, at least one of said sensors detecting the temperature in a tumor within a patient and at least another of said sensors detecting the temperature in normal tissue of a patient;

means for obtaining a tumor temperature control signal from said tumor sensor;

means for obtaining a normal temperature control signal from said normal sensor;

means for storing a predetermined therapeutic tumor control temperature in said data memory unit;

means for storing a predetermined normal tissue threshold temperature in said data memory unit; and

means for applying said tumor temperature control signal and said normal tissue control signal to said electronic digital signal processor, said processor adjusting said power input control means to individually control the power input to each of said applicators in response to said tumor control signal for maintaining the tumor temperature at said predetermined tumor control temperature and said processor adjusting said power input control means in response to said normal tissue control signal exceeding said predetermined threshold value, whereby when said normal tissue control signal indicates a normal tissue temperature in excess of the threshold value, the power input to selected ones of said microwave applicators is decreased, overriding the tumor temperature control signal while optimizing the distribution of power input to the microwave applicators to maintain temperature in the tumor at the predetermined therapeutic tumor control temperature.

9. In a hyperthermia treatment system including a power generator, a plurality of energy applicators powered by the power generator for transmitting energy to tissue, and a power input control for each of the applicators to vary the power input to the applicators from the power generator, wherein the improvement comprises:

at least one multiple semiconductor temperature sensor for use with a monochromatic light transmitter and a light intensity detector for providing multiple temperature measurements linearly along the sensor, said semiconductor temperature sensor including a plurality of semiconductor crystals spaced a predetermined distance apart along the central axis of a housing member and a pair of fiber optic cables connected to each of said semiconductor crystals for transmitting a monochromatic light to each of said crystals along one of said cables and transmitting the reflected light along the other of said cables to the light intensity detector, whereby a linear array of temperature is sensed along the axis of the sensor, the temperatures in both the tumor and the region of normal tissue subject to treatment being actively monitored, including means for generating a temperature control signal for each temperature sensed by one of said sensors;

a first means for generating a control signal to selected ones of the power input controls of the applicators in response to said temperature control signal from said sensors for the tumor for maintaining a temperature within the tumor at a predetermined control temperature;

a second means for generating a control signal to selected ones of the power input controls to the applicators in response to a temperature control signal from said sensors in a region of normal tissue indicating a temperature in excess of a threshold temperature;

means for said second control signal to override said first control signal to decrease the power input to selected ones of said applicators, whereby the normal tissue is protected by keeping it below the predetermined threshold temperature while maintaining the temperature within the tumor at the predetermined control temperature.

10. In a hyperthermia treatment system including a power generator, a plurality of applicators powered by the power generator, and a power input control for each of the applicators to vary the energy input to the applicators from the power generator, wherein the improvement comprises:

multiple temperature sensors for actively monitoring the temperatures of both the tumor and the region of normal tissue subject to treatment, including means for generating a temperature control signal for each of said sensors;

a first means for generating a control signal to selected ones of the power input controls of the applicators in response to said temperature control signal from said sensors for the tumor for maintaining the temperature within the tumor at a predetermined control temperature;

a second means for generating a control signal to selected ones of the power input controls of the applicators in response to a temperature control signal from said sensors in a region of normal tissue indicating a temperature in excess of a threshold temperature; and

means for determining the heating effects of each of the individual applicator in the tumor and normal tissue, said means for determining the heating effects compensating for variation in the heating effects due to blood perfursion; and

means for optimizing the energy input to each of the applicators by use of the power input controls to protect the normal tissue by keeping it below the predetermined threshold temperature while maintaining the temperature within the tumor at the predetermined control temperature.