WO2019124885A1

WO2019124885A1 - Applicator structured both for permittivity measurement and hyperthermic treatment

Info

Publication number: WO2019124885A1
Application number: PCT/KR2018/015920
Authority: WO
Inventors: 서광석; 권영우; 오성욱; 서태윤; 조제원; 허여울
Original assignee: 서울대학교 산학협력단; 가톨릭관동대학교 산학협력단
Priority date: 2017-12-20
Filing date: 2018-12-14
Publication date: 2019-06-27
Also published as: KR101929354B1

Abstract

The present invention relates to a technology wherein an applicator can be used both for a function of measuring the permittivity of a biological tissue and a function of performing hyperthermic treatment. According to the present invention, an impedance matching network operating at a predetermined frequency is formed on a microstrip line of an applicator which is used to measure the permittivity of a biological tissue, and thus both a function of measuring the permittivity of a biological tissue and a function of performing hyperthermic treatment without reflection loss can be achieved by a single applicator.

Description

An applicator having a permittivity measurement and a high-temperature therapy combination structure

TECHNICAL FIELD The present invention relates to a technique for measuring a permittivity of a living tissue and a function for performing a high-thermal therapy using an applicator. More particularly, the present invention relates to an applicator for measuring a permittivity of a living tissue, To an applicator having an impedance matching network and measuring a permittivity of a living tissue with one applicator and a permittivity measurement and high heat therapy therapy structure capable of performing a hyperthermia therapy function.

Since the permittivity has different values depending on the moisture content of the living tissue, it can be used as a basis for distinguishing between normal tissue and abnormal tissue (tumor, etc.) and can be used as a radio frequency And can be used as basic data for development of applicator using microwave.

It is known that various probes exist as a mechanism for measuring the dielectric constant of living tissue. Among them, an open-ended coaxial probe is reported to be widely used for dielectric constant measurement. An open coaxial line is capable of measuring the dielectric constant at a wide frequency range and has the advantage of minimizing invasion by being a thin and long form.

High-heat therapy refers to topical therapy that cures solid cancer tissues using microwaves, lasers, and microwaves. High-temperature therapy using microwaves is based on the principle that microwave energy interacts with water molecules contained in human tissues to generate heat. Such therapies for hyperthermia include far field radiation and near field radiation.

The treatment of hyperthermia therapy using the distal field radiation is treatment of treating the tumor by increasing the temperature of the tumor using microwave or high frequency. An antenna or an array antenna is mainly used for this treatment.

When an applicator is used for hyperthermia therapy using near field radiation, the electromagnetic field energy is concentrated at the interface between the probe and the living tissue, and the living tissue is chemically and physically changed. As a result, the impedance of the living tissue is changed to change the reflection coefficient.

As described above, when the applicator for the high-temperature therapy according to the prior art is used, there is a disadvantage that the return loss increases due to the impedance change of the biotissue with time and the power efficiency is lowered.

An object of the present invention is to provide an impedance matching network that operates at a specific frequency in an applicator used for measurement of dielectric constant of a living body tissue so as to infiltrate a very high frequency into biological tissues and generate reflected waves of appropriate intensity One applicator is to measure the permittivity of biotissue and to perform the hyperthermia therapy function.

According to an aspect of the present invention, there is provided an applicator having a permittivity measurement and a high-thermal therapy therapy structure, the applicator comprising: a conductive body; A dielectric filled in the inner space of the conductor; A microstrip line and a strip line formed in the dielectric body in the horizontal direction to transmit a very high frequency signal supplied from the outside; A conductor via formed in a vertical direction at one end of the strip line; A coaxial line opening surface formed on the conductive body so as to be connected to the conductor via to irradiate the living tissue of the affected part with the very high frequency signal; And an impedance matching network formed on the microstrip line.

The present invention provides an impedance matching network that operates at a specific frequency in an applicator used for measuring the dielectric constant of a living tissue. The impedance matching network can penetrate a living tissue into a living tissue and generate a reflected wave of a proper intensity. It is possible to perform the function of measuring the dielectric constant and the function of the high-thermal therapy without reflection loss, and the power efficiency is prevented from being lowered due to the impedance change of the living tissue.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view of an applicator having a permittivity measurement and a high-thermal therapy combination structure according to the present invention; Fig.

FIG. 2 is a bottom view of an applicator having a permittivity measurement and a high-temperature therapy combination structure according to the present invention. FIG.

FIG. 3 is a plan view of an applicator having a permittivity measurement and a high-temperature therapy combination structure according to the present invention. FIG.

4 is a graph showing the dielectric constant measurement result of the applicator according to the present invention.

Figure 5 is a graph of experimental results of high-thermal therapy using an applicator according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view of an applicator having a permittivity measurement function and a high-temperature therapy combination structure according to the present invention. FIG. 2 and FIG. 3 are schematic views of an applicator having a dielectric constant measurement and a high-temperature therapeutic combination structure according to the present invention.

1 to 3, an applicator 10 according to the present invention having a dielectric constant measurement and a high-thermal therapy therapy structure includes a conductor 1, a dielectric 2 filled in an inner space surrounded by the conductor 1, , A micro strip line (3A) formed in a region where one side is exposed in the entire area of the dielectric (2) with respect to a horizontal direction, and a strip line (3B) formed in a region surrounded by the dielectric 3B), a conductor via 4 formed in a vertical direction at one end of the strip line 3B, and a coaxial line opening surface (not shown) formed in a structure connected to the conductor via 4 on the conductor 1 5 and an impedance matching network 6 formed in the microstrip line 3A.

According to the present invention, the applicator 10 has a structure capable of performing both the function of measuring the dielectric constant of the living tissue and the function of the high-thermal therapy without reflection loss. The shape of the applicator 10 is not particularly limited, but may be formed in a cylindrical shape, a square shape, or the like. In the present embodiment, the applicator 10 is described as being formed in a cylindrical shape.

The conductor 1 is formed at the outermost portion of the applicator 10 and has a structure in which one side is exposed in a half region of the applicator 10 with respect to the horizontal direction and the other outermost portion is surrounded, In the region of the outermost region.

The dielectric 2 is filled in the inner space surrounded by the conductor 1 and filled in the exposed surface in the half area of the applicator 10 with respect to the horizontal direction and in the half area of the applicator 10 in the other half area 10).

The micro strip line 3A and the strip line 3B are connected to each other in series to transmit a very high frequency signal supplied from the outside to the direction of the living tissue of the subject to be treated. The micro strip line 3A is formed in a region where one side is exposed with respect to the horizontal direction in the entire area of the dielectric 2, and the strip line 3B is formed in the entire region, (2).

The conductor vias 4 are formed on the opposite ends of the strip line 3B on the opposite ends of the ends connected to the microstrip line 3A so as to be perpendicular to the microstrip line 3A and the strip line 3B. And transmits a very high frequency signal, which is supplied through the biosensor, to the direction of the living tissue of the treatment target.

The coaxial line opening surface 5 is formed on the opposite end of the conductor connected to the string line 3B of the conductor vias 4 at both ends of the conductor via 4, And has an opening surface. The size and shape of the coaxial line opening surface 5 are preferably determined according to the frequency range of the dielectric constant to be measured and the frequency of the microwave signal.

Therefore, the microwave supplied from the outside is infiltrated into the living tissue of the affected part sequentially through the microstrip line 3A, the strip line 3B, the conductor via 4 and the coaxial line opening surface 5 sequentially. Accordingly, heat is generated in the biotissue, and a high-temperature therapy is accordingly performed.

At this time, a reflected wave signal reflected from the living tissue of the affected part passes through the opposite path of the microwave supply path, that is, the coaxial line opening surface 5, the conductor via 4, the stripline 3B, the microstrip line 3A, And the connector (not shown in the drawing) to the reflected wave measurement equipment (eg, scatterometer measurement equipment, network analyzer). Accordingly, the dielectric constant of the living tissue can be measured based on the reflected wave signal transmitted through the applicator 10.

However, when the magnitude of the reflected wave signal reflected from the living tissue is too small, it is difficult to obtain the permittivity information from the reflected wave signal. On the contrary, when the magnitude of the reflected wave signal is too large, It is possible to obtain only the permittivity information of the dielectric constant. Therefore, when measuring the dielectric constant of the living tissue using the applicator 10, the coaxial line opening surface 5 must be fabricated so that an appropriate sized reflected wave signal is generated.

The impedance matching network 6 is formed in the microstrip line 3A and matches the impedance at a specific frequency among the microwave signals in a state where the coaxial line opening surface 5 is in contact with the living tissue of the affected part, So that the intensity of the signal is reduced to a desired level. Accordingly, among the microwave signals of various frequencies, only the microwave signal of the specific frequency is well penetrated into the living tissue, thereby generating heat required for the treatment of hyperthermia.

The shape of the impedance matching network 6 is not particularly limited. In the present invention, an open stub shape of a triple structure is taken as an example in FIG. 3 in consideration of electrical length and manufacturing convenience.

FIG. 4 shows the relative complex permittivity measurement results and reference values for fat of pork, muscle of pork, 0.9% saline solution in the frequency band of 1 GHz to 20 GHz using the applicator 10 The results of the comparison of the experimental results show that reliable measurement results are obtained.

FIG. 5 is a graph of an experimental result obtained by performing hyperthermia treatment on pork muscle using the applicator 10. When the impedance matching network 6 is not used, the temperature of the affected area gradually increases to reach about 50 degrees after 5 minutes. However, when the impedance matching network 6 is used, the temperature of the affected area rises to about 70 degrees It can be confirmed that the efficiency of hyperthermia therapy is improved.

Although the preferred embodiments of the present invention have been described in detail above, it should be understood that the scope of the present invention is not limited thereto. These embodiments are also within the scope of the present invention.

Claims

Conductor;

A dielectric filled in the inner space of the conductor;

A microstrip line and a strip line formed in the dielectric body in the horizontal direction to transmit a very high frequency signal supplied from the outside;

A conductor via formed in a vertical direction at one end of the strip line;

A coaxial line opening surface formed on the conductive body so as to be connected to the conductor via to irradiate the living tissue of the affected part with the very high frequency signal; And

And an impedance matching network formed in the microstrip line. The applicator according to claim 1, wherein the impedance matching network is formed in the microstrip line.
2. The device of claim 1,

Wherein the applicator has a structure in which one side of the outermost side of the applicator is exposed in the horizontal direction and the entire outermost side is surrounded in the other half of the applicator.
The method of claim 1, wherein the microstrip line

And an applicator having a dielectric constant measurement and a high-thermal-therapy therapeutic structure, wherein the applicator is formed in a region of the entire region of the dielectric, the one side of which is exposed in the horizontal direction.
The method of claim 1, wherein the stripline

Wherein an entire surface of the dielectric body is formed at a central portion of a region surrounded by the dielectric with respect to a horizontal direction in the entire region of the dielectric body.
The method of claim 1, wherein the size and shape of the coaxial line opening surface

Wherein the frequency of the dielectric constant of the living tissue is determined according to the frequency range of the dielectric constant of the living tissue and the frequency of the RF signal.
2. The apparatus of claim 1, wherein the impedance matching network

And a function of matching the impedance at a specific frequency among the super-high frequency signals in a state where the opening surface of the coaxial line is in contact with the living tissue, so that intensity of a reflected wave signal from the living tissue is generated to a desired degree. An applicator having a combination of measurement and hyperthermia therapy.
2. The apparatus of claim 1, wherein the impedance matching network

An applicator having a triple open stub structure and a permittivity measurement and a high-temperature therapeutic combination structure.