JPH0634834B2 - Hyperthermia device - Google Patents

Description

Detailed Description of the Invention A. TECHNICAL FIELD The present invention relates to a hyperthermia device used for hyperthermia treatment of cancer tissue, and more particularly to a cavity resonator type hyperthermia device.

B. 2. Description of the Related Art Conventionally, the following methods are known as hyperthermia devices.

Dielectric heating method In this method, electrodes are set on the abdomen side and back side of the patient, and a high frequency electric field of about 8 MHz is applied between both electrodes to generate a high frequency electric field in the body, and by dielectric heating, It kills cancer tissue.

Electromagnetic radiation method This method radiates electromagnetic waves into the body by setting a radiation type applicator (waveguide) near the patient and applying a high frequency voltage of about 1000 MHz to the radiation type applicator. It kills the organization.

In the above method, the electrode (or applicator)
By interposing a bolus, which is a bag in which a dielectric substance having a dielectric constant substantially equivalent to that of the human body is enclosed, between the patient and the body surface of the patient, the reflection of heating energy on the human body surface is suppressed and I am trying to cool.

C. However, the conventional device described above has the following problems.

In the dielectric heating method, since the electric lines of force between the electrodes act so as to widen the distance between them in the patient's body, it is difficult to locally heat the affected area deep inside the body. is there.

In addition, the electromagnetic wave radiation method (1) has a problem that it is difficult to locally heat the affected area deep inside the body because the frequency is high and the attenuation on the body surface is large.

The present invention has been made in view of such circumstances, and an object thereof is to provide a hyperthermia device capable of locally and selectively heating a diseased part at an arbitrary position deep inside the body. There is.

D. Means for Solving the Problems The present invention has the following configuration in order to achieve the above object.

That is, the present invention is a hyperthermia device for performing thermal treatment by setting a treatment area of a subject in a cavity resonator, and enclosing a liquid having a dielectric constant substantially equivalent to the human body so as to surround the subject. The non-metallic liquid container described above is provided in the cavity resonator, and the liquid container is movable.

E. Effect According to the present invention, by moving the liquid container, it is possible to move the electric field distribution itself generated in the liquid inside the liquid container. Therefore, the affected part of the subject is selectively heated locally by moving the liquid container so that the part of the electric field distribution where the electric field intensity has a maximum value matches the affected part of the subject.

F. Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing the outline of the configuration of an embodiment of the present invention, FIG. 2 (a) is a transverse sectional view thereof, FIG. 2 (b) is a longitudinal sectional view thereof, and FIG. 3 is a liquid container. It is a cross-sectional view showing an electric field distribution generated inside.

Reference numeral 1 is a rectangular cavity resonator in which openings 2 for inserting the subject M are provided on the front and rear sides. A feed point 4a is provided at the center of the upper surface of the cavity resonator 1 when the probe feed is performed, and a feed point 4b is provided at the center of the side surface when the loop feed is performed. By supplying high-frequency power of a predetermined frequency to the feeding point 4a or the feeding point 4b, the cavity resonator 1 has a mode in which the electric field strength is maximized in the central portion thereof, for example, a TE ₃₂₁ mode electric field distribution. Is obtained (see FIG. 3). That is, T
According to the electric field distribution of the E ₃₂₁ mode, the electric field strength can be maximized in the central portion of the cavity resonator 1 into which the subject M is inserted, so that the affected area deep inside the body of the subject M is locally heated. It can be said that it is preferable in terms of points.

A plurality of cutouts 5 are provided around the opening 2, and between the cutouts 5 that are opposed to each other with the opening 2 interposed therebetween, a thumbscrew 10 is provided at each end of the conductiveness. Band 6 is spanned. The thumbscrew 10 is attached so as to be slidable in the length direction of the cutout portion 5, and its position can be held by a tightening operation. Thereby, after inserting the subject M into the opening 2, the length of the conductive band 6 can be adjusted so as to be along the body surface of the subject M, and the gap between the openings 2 is defined by the conductive band 6. By covering
The disturbance of the electric field distribution generated in the cavity resonator 1 can be reduced.

A cylinder 7 made of a non-metallic material such as acrylic resin is provided before and after the opening 2, and a bolus 3 made of an elastic material such as silicone rubber is provided on the inner peripheral surface of the cylinder 7. It is provided. At the front of the bolus 3 is a water inlet 1
4 is attached and after inserting the subject M into the cylinder 7,
By supplying a liquid equivalent to the relative dielectric constant of the human body from a water supply device (not shown), the bolus 3 is brought into close contact with the subject M.

As in the cavity resonator 1, a rectangular liquid container 8 is provided inside the cavity resonator 1 in a state of penetrating the cylinder 7 at the center thereof. Like the cylinder 7, the liquid container 8 is made of a non-metallic material such as acrylic resin, and front and rear side surfaces through which the cylinder 7 penetrates are cut out concentrically with the cylinder 7. A bolus 9 made of an elastic material such as silicone rubber is provided in the cutout portion, and the bolus 9 is in close contact with the outer peripheral surface of the cylinder 7. A liquid similar to the liquid supplied to the bolus 3 is enclosed in the liquid container 8 and the bolus 9.

A first moving mechanism 11 as a moving mechanism that supports the liquid container 8 and moves the liquid container 8 in the up-down direction is attached to the bottom surface of the liquid container 8, and moves the liquid container 8 in the left-right direction on the side surface. The 2nd moving mechanism 12 as a moving mechanism to make it attached is attached. A partition wall 23 that constitutes an inner wall of the cavity resonator 1 is provided between the moving mechanisms 11 and 12 and the liquid container 8, and the partition wall 23 has a first and a second movement. Notched portions (not shown) that allow the movement of the mechanisms 11 and 12 are provided. Partition wall 23
Than the two moving mechanisms 11 and 12 protruding inward
The part is made of a non-metallic material so as not to disturb the electric field distribution generated in the partition wall 23.

The first moving mechanism 11 and the second moving mechanism 12 include a guide rail 20, a moving table 18 that slides on the guide rail 20, and a hydraulic actuator 15 provided on the moving table 18. It consists of The upper surface of the piston of the hydraulic actuator 15 is fixed to the corresponding outer surface of the liquid container 8. The piston displacement amount of the hydraulic actuator 15 is controlled by the control unit 13 so that the liquid container 8 can be moved by a required distance.

Next, the operation of the apparatus of the above-described embodiment will be described.

FIG. 4 shows the moving state of the liquid container 8.
(a) is a transverse sectional view showing a steady state, (b) is a transverse sectional view showing a horizontal moving state, (c) is a transverse sectional view showing a vertical moving state .

In these drawings, the cavity resonator 1 surrounding the liquid container 8 and the control unit 13 connected to the hydraulic actuator 15 are omitted.

(1) Steady state First, after inserting the subject M into the opening 2, a liquid having a relative dielectric constant equivalent to that of the human body is supplied from the water supply port 14 to the bolus 3.
The bolus 3 is brought into close contact with the body surface of the subject M. Next, for example, TE ₃₂₁ mode electric field distribution (see FIG. 3) is generated in the cavity resonator 1 by probe feeding or loop feeding. At this time, the wavelength of the electromagnetic wave in the liquid is equal to the wavelength of the electromagnetic wave in the air layer due to the difference between the non-dielectric constant of the air layer between the inner wall of the cavity resonator 1 and the liquid container 8 and the liquid in the liquid container 8. Compared to about 1/8. Therefore, most of the electric field distribution generated in the cavity resonator 1 is generated in the liquid container 8. According to the electric field distribution of the TE ₃₂₁ mode generated in the liquid container 8, the electric field strength at the center of the liquid container 8 becomes maximum, and the affected part A of the subject M located at the center is locally heated. It

(2) Horizontal movement The operation of heating the affected part B at a position horizontally separated from the center of the body of the subject M will be described.

First, the horizontal distance between the center position of the subject M and the position of the affected area B is measured by visually observing a tomographic image or the like of the heated cross section, and the obtained horizontal distance is input to the control unit 13. Control unit 13
Controls the piston displacement amount of the hydraulic actuator 15 according to the given horizontal distance information. As the piston of the hydraulic actuator 15 is displaced, the liquid container 8 and the cylinder 7
The bolus 9 provided between and is deformed by its elastic action, and allows the liquid container 8 to move in the horizontal direction. Further, the moving base 18 of the first moving mechanism 11 provided on the bottom surface of the liquid container 8 also moves horizontally along the guide rails 20 (see FIG. 4 (b)).

As the liquid container 8 moves in the horizontal direction, the liquid container 8
The electric field distribution generated in the inside apparently moves in the horizontal direction,
The maximum point of the electric field strength at the center is located on the affected part B, and the affected part B is locally heated.

(3) Vertical movement In the case of locally heating the affected area C at a position distant in the vertical direction with respect to the center position in the body of the subject M, the hydraulic actuator 15 of the first moving mechanism 11 is required to have a required distance. By only changing the temperature, the liquid container 8 can be moved in the vertical direction (see FIG. 4 (c)), and the affected area C can be locally heated.

The present invention can be modified as follows.

In the above-described embodiment, the liquid container 8 is movable in two directions orthogonal to the body axis of the subject M, but it may be configured to move in the body axis direction of the subject M as well. In this case,
A moving mechanism similar to the first and second moving mechanisms 11 and 12 may be provided on the front surface or the back surface of the inner wall of the cavity resonator 1. Further, in the above-described embodiment, the liquid container is driven by the hydraulic actuator, but it goes without saying that it may be driven by a motor or the like.

In the above-described embodiment, the elastic action of the bolus 9 is used to allow the movement of the liquid container 8. However, this is because the side surface of the liquid container 8 and a part of the upper and lower surfaces thereof are formed into a bellows shape. You may comprise so that the movement of the container 8 may be permitted by the expansion-contraction action of this bellows part. Alternatively, the liquid container may be configured to have a fitting structure with a water leakage prevention structure, and the fitting amount may be variable to move the liquid container.

In the above-described embodiment, the cavity resonator 1 has a rectangular shape, but this can be similarly implemented with the cylindrical cavity resonator 1.

G. EFFECTS OF THE INVENTION As is apparent from the above description, the hyperthermia device according to the present invention is provided in the cavity resonator and is provided to the subject M.
Since the liquid container for taking in is movable, the maximum point of the electric field strength can be made to coincide with the affected area without moving the subject, and local heating of any part of the subject can be effectively performed. .

[Brief description of drawings]

1 to 4 relate to an embodiment of the present invention. FIG. 1 is a perspective view showing a schematic configuration of an apparatus, FIG. 2 (a) is a cross-sectional view thereof, and FIG. Fig. 3 is a vertical sectional view, Fig. 3 is an electric field distribution diagram inside the container, and Fig. 4 is a lateral sectional view of the liquid container used for explaining the operation of the device. Fig. 4 (a) is a steady state, Fig. 4 (b) is horizontal. A directional movement state, and FIG. 7C shows a vertical movement state. DESCRIPTION OF SYMBOLS 1 ... Cavity resonator, 7 ... Cylinder 8 ... Liquid container, 9 ... Bolus 11 ... 1st drive mechanism 12 ... 2nd drive mechanism

Claims (1)

[Claims] 1. A hyperthermia device for performing thermal treatment by setting a treatment area of a subject in a cavity resonator, wherein a liquid having a dielectric constant substantially equivalent to that of a human body is enclosed so as to surround the subject. A hyperthermia device comprising a non-metallic liquid container provided in the cavity resonator, and the liquid container being movable.