JP2007244748A - Needle for heating living body and therapy instrument using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a needle for heating a living body, providing a heat generation characteristic which is sufficient to cauterize a diseased site by using ferromagnetic metal. <P>SOLUTION: The needle 1 for heating the living body punctures the diseased site in the living body, heats it with an alternating magnetic field, and cauterizes the diseased site 10b. The needle 1 includes a heat generating part 4 made of the ferromagnetic metal arranged inside a needle tube 2. The needle tube 2 is heated by the heat generation of the heat generating part 4 to heat up to diseased site cauterizing temperature. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a living body heating needle that uses a ferromagnetic metal that generates heat in an alternating magnetic field as a heat generating portion and heats the affected portion such as cancer to cauterize the affected portion, and a treatment instrument using the living body.

  As shown in Patent Document 1, the present applicant has proposed a treatment method in which a ferrite material is heated with an alternating magnetic field to cauterize cancer or the like. This method is advantageous compared to radiofrequency ablation therapy and microwave coagulation therapy in that it can be used for a wide range of ablation, can cope with scattered cancers, and can precisely control the ablation range.

  By the way, as an alternative to this ferrite material, there are ferromagnetic metals such as iron, cobalt and nickel. However, a ferromagnetic metal alone generates too much heat in an alternating magnetic field and is not suitable for living body ablation. Further, it has a problem that it is easily ionized by body fluids or the like. Furthermore, iron, which is a representative ferromagnetic metal, has a characteristic that it is easily oxidized.

  In Patent Document 2, a ferromagnetic material is administered to a human body, and the above-mentioned problems cannot be solved.

International Publication No. 2004/016316 Pamphlet JP-A-56-160720

  The present invention has been made in view of the above-described problems, and its object is to make the heat generation of the ferromagnetic metal a heat generation temperature suitable for ablation of a living body, and to easily ionize with a body fluid or the like. It is an object of the present invention to provide a living body heating needle and a treatment instrument using the same.

  The living body heating needle according to the present invention punctures the affected part in the living body and heats the affected part with an alternating magnetic field. The heat generating part made of a ferromagnetic metal that generates heat by the alternating magnetic field is used as a hollow part of a biocompatible needle tube. It is formed by filling all or part of the core part. In addition, the ferromagnetic metal here is a ferromagnetic metal in a narrow sense except for ferrite having ferrimagnetism.

  Here, the needle tube is a biocompatible metal such as titanium or stainless steel, and by covering the ferromagnetic metal serving as the heat generating part, the heat generation of the ferromagnetic metal is suppressed by the magnetic shielding effect, and the whole is made of the living body. The exothermic temperature is suitable for shochu and ionization is prevented by body fluids. In such a living body heating needle, the heat generation position can be controlled by the position of the ferromagnetic metal in the air core part in the needle tube. That is, the living body heating needle according to the present invention can generate heat when a ferromagnetic metal is provided on the entire air core, and can be provided if a ferromagnetic metal is provided on a part of the air core. Heat can be generated around the portion.

  Here, as the needle tube, for example, a commonly used injection needle can be used. However, when the injection needle is used, the blade tip and the hole of the needle base into which the drug solution is injected into the living body are blocked with a biocompatible material. The

  Also, the needle tube is provided with a protrusion or flange-like protrusion on the needle base side, and this protrusion can be used as a guide for the depth of puncture or as an operation part at the time of removal.

  The living body heating needle according to the present invention as described above can cauterize the affected part by puncturing the affected part with a single body or multiple copies and causing the affected part to generate heat. For cauterization of the affected area, there are a method of laparotomy and puncturing a living body heating needle into the affected area, and a method of conveying the living body heating needle through a catheter and puncturing the affected area.

  Furthermore, a plurality of living body heating needles according to the present invention can be erected on the base portion to constitute the treatment instrument according to the present invention. Thereby, a plurality of living body heating needles can be punctured at a time on the affected area. That is, ablation treatment can be performed over a wide range.

  According to the present invention, since the ferromagnetic metal serving as the heat generating part that generates heat by the alternating magnetic field is provided in the air core part in the needle tube, the ferromagnetic metal is not in direct contact with the living body and is ionized by a body fluid or the like. The point can be solved. Further, the magnetic shielding effect of the needle tube suppresses the heat generation of the ferromagnetic metal, and the entire heat generation temperature can be set to a temperature suitable for ablation of a living body.

  Hereinafter, a living body heating needle to which the present invention is applied will be described with reference to the drawings. As shown in FIGS. 1 (A) and 1 (B), a living body heating needle 1 to which the present invention is applied has a heating part 4 made of a ferromagnetic metal on all or part of an air core part 3 of a needle tube 2. Is provided.

  Here, the needle tube 2 is, for example, a commonly used injection needle, and is formed of a biocompatible metal such as a stainless tube or a titanium tube. The air core portion 3 of the needle tube 2 is filled or inserted with a powder or fine wire ferromagnetic metal such as iron, cobalt, nickel, or the like, which becomes the heat generating portion 4 that generates heat in an alternating magnetic field.

  Moreover, the normal injection needle used for the needle tube 2 has a plurality of holes 2a that are continuous with the air core 3 for injecting a chemical into the living body at the blade tip or the needle base. Therefore, the needle tube 2 is closed or sealed with the biocompatible material 5 after filling or inserting a ferromagnetic metal into a part or all of the air core portion 3. As the biocompatible material 5 for sealing the hole 2a, fluorine resin (Teflon, registered trademark), vinyl chloride resin, silicone rubber, polypropylene, polyethylene, polymethyl methacrylate, polystyrene, 4-methylpentene-1 resin Polycarbonate or the like can be used.

  According to the living body heating needle 1 as described above, since the ferromagnetic metal serving as the heat generating portion 4 is covered and sealed with the needle tube 2 such as a biocompatible titanium tube or stainless steel tube, the magnetic shielding effect of the needle tube 2 is achieved. Therefore, the heat generation of the ferromagnetic metal can be suppressed. Further, the needle tube 2 eliminates the direct contact between the living tissue and the ferromagnetic metal, and can solve the problem of being easily ionized.

  Here, the heating device 11 using the living body heating needle 1 as described above will be described. As shown in FIG. 2, the heating device 11 is disposed outside the living body 10a such as a patient and generates an alternating magnetic field. An induction coil 12 is provided. The induction coil 12 is connected to a power supply device and generates an alternating magnetic field having a low frequency of about 100 kHz to 1 MHz when supplied with an alternating current.

  On the other hand, in the living body 10a, the living body heating needle 1 to which the present invention is applied is punctured in the affected part 10b such as cancer. In this heating device 11, an inductive coil 12 generates a low-frequency alternating magnetic field and causes the living body heating needle 1 punctured in the affected part 10b to generate heat, thereby cauterizing the affected part 10b. Specifically, in the living body heating needle 1, the heat generating part 4 made of a ferromagnetic metal generates heat due to an alternating magnetic field, and the affected part 10 b is cauterized through the heated needle tube 2. Here, since the alternating magnetic field to be generated has a low frequency of about 100 kHz to 1 MHz, it is possible to reduce the influence of induction heating other than the affected part 10b. For example, when the affected part 10b is cancer, only the living body heating needle 1 is heated to about 60 ° C. to 80 ° C., which is the ablation temperature of cancer.

  That is, in general, a ferromagnetic metal generates heat due to hysteresis loss and eddy current loss in an alternating magnetic field. The melting of metals and alloys by the high frequency induction heating method that is widely used in industry is based on this principle, and the ultimate temperature is about 1200 ° C. At such a temperature, it cannot be used for living body ablation. As described above, the exothermic temperature necessary for the cauterization of the living body is about 60 ° C to 80 ° C. Therefore, in the living body heating needle 1 to which the present invention is applied, the ferromagnetic metal serving as the heat generating portion 4 is covered with a biocompatible needle tube 2 such as a titanium tube or a stainless tube, so that the entire magnetic shield effect of the needle tube 2 is achieved. The temperature is lowered to a temperature suitable for ablation of the living body.

  Here, the ferromagnetic metal used for the heat generating portion 4 may be an alloy, but it is preferable to use a single element such as iron, cobalt, or nickel as a constituent element in order to reduce examination factors.

  In addition, in connection with the present invention, there is a study on ultra-high temperature hyperthermia (see INNERVISION (18.8) 2003.P33). In this research, cauterization is performed by heating a composite heating element in which a metal ring is attached to a magnetic body by applying a microwave. In this study, when the temperature of the magnetic material is lower than the Curie temperature, magnetic flux concentrates due to the effect of the magnetic material, and the composite heating element generates heat due to the short-circuit current induced in the metal ring, but the temperature of the magnetic material is the Curie temperature. Focusing on the fact that when the temperature is higher, the magnetic body loses magnetism and the concentration of magnetic flux does not occur, so the heat generation of the composite heating element becomes small and constant, and cauterization is performed using the region where the temperature of the magnetic body is higher than the Curie temperature. I am doing so.

  For this reason, a magnetic transformation point (Curie temperature) is set to 768 ° C. by adding many different metal elements to iron, which is a typical magnetic metal, to form a multi-component alloy, and adding many kinds and a large amount of additive elements to iron. (The Curie temperature of iron is 768 ° C.) to about 60 ° C. to 80 ° C.

  However, since the metal used here has a large amount of different kinds of metals added, magnetic dilution occurs and the value of the saturation magnetization (Bs) is significantly reduced. This saturation magnetization (Bs) has a great influence on the heat generation amount and mass. That is, if the saturation magnetization (Bs) is halved, twice the mass is required to obtain the same calorific value. Therefore, when applied to the present invention, the needle tube 2 becomes thicker or longer, and the invasiveness to the living body increases. In addition, the inclusion of various alloy elements increases the factors for studying harmfulness, making it difficult to put it to practical use for medical purposes.

  As described above, the living body heating needle 1 to which the present invention is applied can reduce factors to be examined when a single element ferromagnetic metal such as iron, cobalt, or nickel is used for the heat generating portion 4. It becomes easy.

  Here, FIG. 3 shows a heating experiment result of a living body heating needle using a titanium tube as the needle tube 2 and using an Fe fine wire which is a ferromagnetic metal as the heat generating portion 4. Here, the living body heating needle was immersed in 10 ml of water, an AC magnetic field was applied under conditions of 370 kHz and 140 W, and the water temperature was measured.

Titanium tube: outer diameter: 2.4 mm, inner diameter 1.9 mm (wall thickness: 0.25 mm)
Fe fine wire: outer diameter: 1.9 mm, length: 20 mm, mass: 446.7 mg
FIG. 4 is a result of a heating experiment using only the Fe fine wire used in FIG. 3, and is a diagram when the water temperature is measured by immersing the Fe fine wire in 10 ml of water and applying an alternating magnetic field under conditions of 370 kHz and 140 W. .

  FIG. 4 shows that the Fe fine wire has extremely excellent heat generation characteristics in an alternating magnetic field, and is too hot for ablation of a living body. When the Fe fine wire is covered with a titanium tube, as shown in FIG. 3, heat loss is caused by the magnetic shielding effect of the titanium tube, heat generation characteristics are suppressed, and an appropriate temperature for cauterization of the affected area can be achieved.

  Moreover, FIG. 5 shows the heating experiment result of the living body heating needle using a titanium tube for the needle tube 2 and a super invar alloy fine wire which is a ferromagnetic metal for the heat generating part 4. Here, the living body heating needle was immersed in 10 ml of water, an AC magnetic field was applied under conditions of 370 kHz and 140 W, and the water temperature was measured. In addition, the composition of the used super invar alloy fine wire is as follows.

Composition: Ni ... 31%, Co ... 4-6%, Mn ... 0.3-0.4%, C ... 0.07%, Fe ... Balance
Titanium tube: outer diameter: 2.4 mm, inner diameter 1.9 mm (wall thickness: 0.25 mm)
Super Invar alloy fine wire: outer diameter: 1.9 mm, length: 20 mm, mass: 446.7 mg
FIG. 6 is a result of a heating experiment using only the Super Invar alloy thin wire used in FIG. 5. When the Super Invar alloy thin wire is immersed in 10 ml of water, an AC magnetic field is applied under conditions of 370 kHz and 140 W, and the water temperature is measured. FIG.

  From FIG. 6, it can be seen that the super invar alloy fine wire has extremely excellent heat generation characteristics and is too hot for ablation of a living body. When the Super Invar alloy thin wire is covered with a titanium tube, as shown in FIG. 5, heat loss is caused by the magnetic shielding effect of the titanium tube, the heat generation characteristic is suppressed to about half, and the appropriate temperature for cauterization of the affected area may be achieved. it can.

  Further, FIG. 7 shows a heating experiment result (line A) of a living body heating needle using a stainless steel tube for the needle tube 2 and an Fe fine wire that is a ferromagnetic metal for the heat generating part 4 and a heating experiment result of only the Fe fine wire ( Line B) is shown. Here, a living body heating needle in which an Fe fine wire was inserted as a heat generating portion 4 into the stainless needle tube 2 and an Fe fine wire were punctured directly into a pig lever, and the temperature of the puncture portion was measured with an optical fiber thermometer. An alternating magnetic field was applied under the conditions of 450 kHz and 180 W. Further, as the stainless steel tube used as the needle tube 2, an injection needle (18G thickness) having an outer diameter of 1.2 mm and an inner diameter of 0.9 mm was used. In the heating experiment using only the Fe fine wire, an Fe fine wire having a diameter of 0.8 mm and a length of 20 mm was used.

  With only Fe fine wire (line B), the temperature reaches 180 ° C. in about 2 minutes. However, if Fe fine wire is inserted into the stainless steel tube, heat loss is caused by the magnetic shielding effect of the stainless steel tube, and the heat generation characteristics are suppressed, and the affected part is cauterized. The temperature can be set appropriately. (Line A).

  From the experimental example in which Fe fine wire or Super Invar alloy fine wire is inserted into the ferromagnetic metal of FIGS. 3 to 7 into a titanium tube or a stainless steel tube, the living body heating needle of the present invention is a ferromagnetic metal that generates heat by an alternating magnetic field, It can be seen that while the needle tube 2 loses heat due to the effect of magnetic shielding, the titanium tube and the stainless tube are heated and reach a temperature suitable for cauterization of the affected part 10b.

  As described above, in the living body heating needle 1 of the present invention, the entire needle tube 2 is heated by inserting or filling a ferromagnetic metal serving as the heat generating portion 4 over the entire air core portion 3 of the needle tube 2, and thus a wide range. Shochu can be carried out over a period of time. Further, by inserting or filling the ferromagnetic metal partly instead of the whole air core part 3, a predetermined range centering on the position corresponding to the ferromagnetic metal insertion or filling position of the needle tube 2 is heated, and more Shochu can be done in a fine range.

  Furthermore, as shown in FIG. 1C, the living body heating needle 1 is provided with a protruding projection 6 integrally on the needle base side of the needle tube 2, so that the living body heating needle 1 does not stick too much into the affected area 10b. It can be used as a stopper or a guideline. Further, the protrusion 6 can be used as a hook for locking a wire or the like when the living body heating needle 1 is pulled out from the affected part 10b. Further, as shown in FIG. 1D, the protrusion 6 may be formed in a flange shape by a lid body 6a that closes the hole 2a on the needle base side.

  As described above, the living body heating needle 1 shown in FIG. 1 is used, for example, for puncturing liver cancer, and its length and thickness are determined according to the size, shape, etc. of the affected area. It may be curved.

  FIG. 8 shows a therapeutic instrument 20 in which a plurality of living body heating needles 1 to which the present invention is applied are erected on a base portion 21 formed of a biocompatible resin. This therapeutic instrument 20 can be used, for example, for the treatment of cervical cancer that has occurred in the cervix near the exit of the uterus (portion close to the vagina). That is, the treatment instrument 20 can be inserted from the vagina and puncture the living body heating needle 1 of the base 21 for cervical cancer near the exit of the uterus. The number of living body heating needles 1 erected on the base unit 21 is appropriately determined depending on the size of cervical cancer.

  In the above example, the living body heating needle 1 used for liver cancer and cervical cancer and the therapeutic instrument 20 using the same have been described. However, the affected part where the living body heating needle and the therapeutic instrument of the present invention are used is those tumors. It is not limited to.

It is a figure which shows the biological body heating needle to which this invention is applied, (A) is a perspective view, (B) is sectional drawing, (C) and (D) are perspective views of a modification. It is a figure which shows the heating apparatus used when treating using the biological heating needle to which this invention is applied. It is a figure which shows the heating experiment result of the biological heating needle which used the titanium tube for the needle tube and inserted the Fe fine wire which is a ferromagnetic metal into the heat generating part. It is a figure which shows the heating experiment result only of the Fe fine wire used in FIG. It is a figure which shows the heating experiment result of the living body heating needle which used the titanium tube for the needle tube and inserted the super invar alloy fine wire which is a ferromagnetic metal into the heat generating part. It is a figure which shows the heating experiment result only of the super invar alloy fine wire used in FIG. It is a figure which shows the heating experiment result (line A) of the biological heating needle which used the stainless steel tube for the needle tube, and inserted the Fe fine wire in the heat generating part, and the heating experiment result (line B) only of the Fe fine wire. It is a perspective view of the treatment instrument to which the present invention is applied.

Explanation of symbols

1 living body heating needle, 2 needle tube, 2a hole part, 3 air core part, 4 heat generating part, 5 biocompatible material

International Publication No. 2004/016316 Pamphlet JP-A-55-160720

Biological heated needle according to the present invention is to puncture the affected area of the body, in an alternating magnetic field of low frequency of the order of magnitude not to affect by the induction heating other than the patient part is intended to heat the affected part, the heat generation in an alternating magnetic field a heating unit made of a ferromagnetic metal, filled or inserted from one end to all or part of the air-core portion of the needle tube having a magnetic shielding property and biocompatibility to suppress heat generation of the heat generating portion, and the air-core portion of the needle tube The hole at the continuous end is closed with a biocompatible material different from the needle tube, and the air core filled with or inserted with the ferromagnetic metal is sealed . In addition, the ferromagnetic metal here is a ferromagnetic metal in a narrow sense except for ferrite having ferrimagnetism.

Here, as the needle tube, for example, a commonly used injection needle can be used. However, when the injection needle is used, the blade tip and the hole of the needle base into which the drug solution is injected into the living body are different from the needle tube. Blocked with compatible material.

According to the present invention, the ferromagnetic metal serving as the heat generating portion that generates heat by the alternating magnetic field is provided in the air core portion in the needle tube, and the hole portion of the needle tube is closed with a biocompatible material different from the needle tube. There is no direct contact with the living body, and the problem that it is ionized by body fluids or the like can be solved. In addition, the magnetic shielding effect of the needle tube suppresses the heat generation of the ferromagnetic metal, and the overall heat generation temperature can be set to a temperature suitable for ablation of a living body. Further, the present invention can be formed by a simple method of using a needle tube and closing a hole at an end continuous with the air core portion with a biocompatible material different from the needle tube. Furthermore, according to the present invention, since the heat generating part is filled or inserted into the whole or a part of the air core part of the needle tube from one end, the heat generating position in the needle tube can be easily adjusted.

The living body heating needle according to the present invention punctures the affected part in the living body and heats the affected part with a low frequency alternating magnetic field of about 100 kHz to 1 MHz other than the affected part to reduce the influence of induction heating. A heat generating part made of a ferromagnetic metal that generates heat in a magnetic field is filled or inserted from one end into all or part of the air core part of the magnetic tube and biocompatibility that suppresses heat generation of the heat generating part. The hole at the end continuous with the core is closed with a biocompatible material different from the needle tube, and the air core filled with or inserted with the ferromagnetic metal is sealed. In addition, the ferromagnetic metal here is a ferromagnetic metal in a narrow sense except for ferrite having ferrimagnetism.

  According to the present invention, the ferromagnetic metal serving as the heat generating portion that generates heat by the alternating magnetic field is provided in the air core portion in the needle tube, and the hole portion of the needle tube is closed with a biocompatible material different from the needle tube. There is no direct contact with the living body, and it is possible to solve the problem of ionization by body fluids or the like. Further, the magnetic shielding effect of the needle tube suppresses the heat generation of the ferromagnetic metal, and the entire heat generation temperature can be set to a temperature suitable for ablation of a living body.

Claims (4)

In the living body heating needle that punctures the affected part in the living body and heats the affected part with an alternating magnetic field,
A living body heating needle characterized by filling a heat generating part made of a ferromagnetic metal that generates heat by an alternating magnetic field into all or part of an air core part of a biocompatible needle tube.   The living body heating needle according to claim 1, wherein the needle tube provided with the heat generating portion is sealed with a biocompatible material.   The living body heating needle according to claim 1 or 2, wherein the needle tube is provided with a protrusion on a needle base side. In a therapeutic instrument that heats the affected part by heating the affected part in the living body with an alternating magnetic field,
A treatment instrument comprising a plurality of living body heating needles according to any one of claims 1 to 3 erected on a base portion.

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