JP2010227365A - Electrode for medical device and medical treatment instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrode for a medical device and a medical treatment instrument which are used at a low voltage and suppress a deterioration of treatment performance due to the adhesion of body tissues. <P>SOLUTION: A high-frequency treatment instrument 10 includes an electrode part 1 used by abutting on a subject to be treated. The electrode part 1 includes an electrode body 2 constituted of a metallic material and a coating layer 3 which is formed on the surface of the electrode body 2 by mixing two or more kinds of materials containing each one or more kinds of one or more kinds of high hardness materials with a Vickers hardness higher than that of the metallic material of the electrode body 2 and one or more kinds of conductive materials with electric conductivity higher than that of the metallic material of the electrode body 2. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electrode for a medical device and a medical treatment tool.

2. Description of the Related Art Conventionally, for example, a high-frequency treatment tool that incises or coagulates a living tissue by applying a high-frequency voltage to the living tissue that is an object to be treated is known. In such a high-frequency treatment tool, an electrode for medical equipment that applies a high-frequency voltage in a state of being in contact with a living tissue is used.
In such electrodes for medical devices, the impedance and discharge characteristics of the electrode change due to the biological tissue adhering to the electrode surface during treatment of the biological tissue, and the treatment performance such as sharpness and coagulation performance deteriorates. Therefore, there has been a strong demand for an electrode for medical equipment in which living tissue is difficult to adhere to the electrode surface.
As such a technique, conventionally, it is known to provide a coat layer for reducing adhesion of a living tissue on the surface of an electrode body.
For example, in Patent Document 1, a high-frequency electrode is disposed at the distal end of an electrically insulating sheath that is inserted into and removed from a treatment instrument insertion channel of an endoscope so as to contact the living body and cauterize the contact surface of the living body. An endoscopic high-frequency treatment instrument (medical treatment instrument), wherein a coating made of a metal or an alloy of gold or white metal is formed on a part or all of the high-frequency electrode. The ingredients are listed.
Here, the coating formed on a part of the high-frequency electrode covers at least the electrode surface in a range that is a contact surface with the living body.
Patent Document 2 discloses a bipolar tweezers (medical treatment tool) having a pair of sandwiching portions and having a function of applying high-frequency power to a sandwiched body sandwiched by the pair of sandwiching portions. A bipolar tweezers is described in which the surface of an electrode (medical device electrode) in a clamping part is mirror-finished and a film for preventing scratches is formed on the surface of the electrode.
The film for preventing damage of the bipolar tweezers is made of a titanium nitride film.

JP 2006-68407 A JP 2000-107194 A

However, the conventional medical device electrode and medical treatment tool as described above have the following problems.
In the technique described in Patent Document 1, since the coating on the electrode surface is made of gold, a white metal, or an alloy thereof, it is considered that the living tissue is difficult to be fixed. Since the hardness is lower than that of steel or the like, the electrode surface is easily scratched. When scratches occur on the electrode surface and fine irregularities are formed on the surface, when high-frequency voltage is applied, discharge concentrates on the projections of the irregularities. Heat generation at the part becomes remarkable. Therefore, there is a problem that the living tissue is rapidly dried and solidified, and the living tissue is easily fixed on the electrode surface, and the treatment performance is deteriorated.
In the technique described in Patent Document 2, since a titanium nitride film is formed on the surface of the electrode, the hardness of the surface can be improved compared to stainless steel and the like, and the living body due to the generation of scratches on the surface of the electrode. Although the adhesion of the tissue can be reduced, the surface of the electrode is covered with an insulator. As a result, the impedance becomes larger than that of the conductor electrode, and it is necessary to apply a higher voltage. When the voltage increases in this way, there is a problem that operability as a medical treatment instrument used for a human body is deteriorated.

  The present invention has been made in view of the above problems, and can be used at a low voltage, and can be used for medical device electrodes and medical treatment tools that can suppress deterioration of treatment performance due to fixation of biological tissue. The purpose is to provide.

In order to solve the above-described problems, the medical device electrode of the present invention is a medical device electrode that is used in contact with an object to be treated, the electrode main body made of a metal material, and the metal of the electrode main body A mixture of one or more high-hardness materials having a Vickers hardness higher than that of the material and two or more types of materials each including one or more conductive materials having a higher electrical conductivity than the metal material of the electrode body. And a coat layer formed on the surface of the electrode body.
According to this invention, the coat layer formed on the surface of the electrode body includes at least one kind of high-hardness material having a Vickers hardness higher than that of the electrode body and a conductive material having electric conductivity higher than that of the electrode body. Since more than one kind of materials are mixed, scratches on the electrode surface can be suppressed by the high hardness material, and good impedance can be ensured by the conductive material.

  In the medical device electrode of the present invention, the electrode body is made of stainless steel, and the high-hardness material is chromium (Cr), DLC (diamond-like carbon), chromium nitride (CrN), titanium nitride (TiN). It is preferable to include one or more of titanium aluminum nitride (TiAlN) and titanium carbonitride (TiCN).

  In the medical device electrode of the present invention, the electrode body is made of stainless steel, and the conductive material is made of copper (Cu), gold (Au), aluminum (Al), platinum (Pt), and chromium ( Preferably, one or more of (Cr) are included.

The medical treatment instrument of the present invention includes the medical device electrode of the present invention.
According to this invention, since the medical device electrode of the present invention is provided, the same operation as the medical device electrode of the present invention is provided.

  According to the medical device electrode and medical treatment instrument of the present invention, a coating layer including a high-hardness material having a Vickers hardness higher than that of the electrode body and a conductive material having an electric conductivity higher than that of the electrode body is formed on the surface of the electrode body. Therefore, it can be used at a low voltage, and there is an effect that it is possible to suppress deterioration of treatment performance due to fixation of living tissue.

It is a typical block diagram which shows schematic structure of the medical treatment tool provided with the electrode for medical devices which concerns on embodiment of this invention. It is AA sectional drawing in FIG.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
A medical device electrode and a medical treatment tool according to an embodiment of the present invention will be described.
FIG. 1 is a schematic configuration diagram showing a schematic configuration of a medical treatment instrument including a medical device electrode according to an embodiment of the present invention. 2 is a cross-sectional view taken along line AA in FIG.

  The high-frequency treatment tool 10 of this embodiment is a medical treatment tool for incising and excising a living tissue as a treatment object or coagulating (hemostasis) the living tissue by applying a high-frequency voltage. As shown in FIG. 1, the schematic configuration of the high-frequency treatment instrument 10 includes a grasping portion 4 for an operator to hold by hand, and an electrode portion 1 protruding from the distal end of the grasping portion 4.

The electrode unit 1 is an electrode for medical equipment that applies a high-frequency voltage by contacting a living tissue as a treatment object, and is provided on a shaft portion 2a connected to a high-frequency power source 5 and a distal end side of the shaft portion 2a. The electrode body 2 has a spatula-like treatment portion 2b, and the coat layer 3 is formed on the surface of the shaft portion 2a.
As the material of the electrode body 2, an appropriate metal material can be adopted. In this embodiment, as an example, stainless steel excellent in strength and corrosion resistance, for example, SUS304 is employed.
The Vickers hardness Hv of SUS304 is Hv = 150 to 250, and the electrical conductivity σ is σ = 1.4 × 10 ¹⁶ (1 / Ω · m)).

The coat layer 3 covers the outer surface of the treatment portion 2b of the electrode body 2 with a substantially constant layer thickness, and includes one or more types of high-hardness materials having a Vickers hardness higher than the metal material of the electrode body 2, and the electrode body The film is formed by mixing two or more kinds of materials each including one or more kinds of conductive materials having electric conductivity higher than that of the metal material of No. 2. Here, mixing means that a high hardness material and a conductive material are mixed at least on the surface of the coat layer 3.
Thereby, as shown in FIG. 2, the treatment portion 2 b is covered with the coat layer 3 on both the front and back surfaces in the thickness direction.
The layer thickness of the coat layer 3 may be an appropriate layer thickness depending on the required surface hardness and conductivity, but is preferably 0.5 μm to 30 μm, for example. When the layer thickness is less than 0.5 μm, the surface roughness due to normal machining (cutting, grinding, etc.) cannot be covered by the coat layer 3, and the base material of the treatment portion 2b is exposed. On the other hand, if the layer thickness exceeds 30 μm, the possibility of cracking due to internal stress of the coat layer 3 increases. The layer thickness of the coat layer 3 is more preferably 4 μm to 10 μm. By setting the layer thickness to 4 μm or more, it becomes possible to prevent the substrate from being exposed even in parts obtained by processing that increases the surface roughness, such as forging, etc. Can also be covered. In addition, by setting the layer thickness to 10 μm or less, it becomes possible to prevent the coating layer 3 from being cracked or peeled off due to a difference in thermal expansion coefficient between the base material of the treatment portion 2 b and the coating layer 3 due to heating or cooling.
Further, the number of types of the high-hardness material and the conductive material is not particularly limited as long as one or more types are included, and two or more types are included.
Moreover, as long as the hardness and impedance of the electrode part 1 can be kept favorable, the Vickers hardness and the electrical conductivity may include a material that is equal to or less than the electrode body 2.
The impedance of the electrode part 1 is preferably 0.1Ω or more and 1000Ω or less.

  As an example of the high hardness material, when the electrode main body 2 is made of stainless steel as in the present embodiment, Cr (Hv = 800 to 1000), DLC (Hv = 800 to 1500), CrN (Hv = 1200). ~ 1800), TiN (Hv = 1300-1900), TiAlN (Hv = 2000-2600), and TiCN (Hv = 2800-3200) may be used.

As an example of the conductive material, when the electrode body 2 is made of stainless steel as in this embodiment, Cu (σ = 59 × 10 ¹⁶ (1 / Ω · m)), Au (σ = 45. 2 × 10 ¹⁶ (1 / Ω · m)), Al (σ = 37 × 10 ¹⁶ (1 / Ω · m)), Pt (σ = 9.4 × 10 ¹⁶ (1 / Ω · m)), and A material containing one or more of Cr (σ = 7.5 × 10 ¹⁶ (1 / Ω · m)) can be used. Here, the electric conductivity σ showed a value of 25 ° C.

Such a coat layer 3 can be formed by PVD methods such as sputtering, ion plating, etc., targeting high hardness materials and conductive materials, CVD methods using heat, plasma, laser, or plating. It is not limited. In addition, the mixing ratio of each material can be adjusted by changing the film formation rate ratio of each material or the amount of reactive gas introduced.
For example, when a single metal such as Cr, Cu, Au, or Pt is formed, it is preferable to use a magnetron DC sputtering method or an ion plating method because the film forming apparatus is simple and the film forming speed is high. When depositing a compound such as CrN, TiN, or TiCN, a reactive sputtering method in which nitrogen gas is flowed while sputtering Cr, Ti, C, or the like, or a target material prepared at a desired ratio is prepared, and an RF sputtering method is used. It is also possible to form a film. In addition, the CVD method uses organic gas, so it is necessary to remove residual impurities and exclude raw material gas. However, since the coating film has good throwing power, it can be used to coat complex shapes such as forceps cups. Suitable for

The operation of the high-frequency treatment instrument 10 having such a configuration will be described.
The high-frequency treatment instrument 10 applies a high-frequency voltage to the electrode portion 1 of the high-frequency treatment instrument 10 by the high-frequency power source 5 with the counter electrode 6 attached to the patient, and the operator applies the electrode portion 1 to the treatment target portion of the patient. Of these, the portion corresponding to the treatment portion 2b covered with the coat layer 3 is used in contact.
At this time, a high-frequency current is generated between the electrode portion 1 and the counter electrode plate 6 via the coat layer 3, but the contact portion between the electrode portion 1 and the living tissue is extremely small compared to the electrode area of the counter electrode plate 6. Because of the area, the current density becomes extremely large only in the vicinity of the contact portion between the electrode portion 1 and the living tissue, and Joule heat is generated. At this time, if the temperature rise is moderate, the tissue is dried and denatured due to the evaporation of moisture, and the tissue is solidified. When the temperature rise is rapid, the carbonization of the tissue is likely to proceed, and the tissue is easily fixed to the electrode portion 1.

At that time, if a fine uneven portion is formed on the surface of the electrode portion 1 in contact with the living tissue by, for example, a scratch or an abrasion, the fine protruded portion or the edge portion included in such an uneven portion is formed. Discharge occurs in a concentrated manner, and carbonization due to a rapid temperature rise occurs even at a site where the tissue is supposed to be solidified by a moderate temperature rise, and tissue fixation occurs locally.
In the electrode part 1 of the present embodiment, the coating layer 3 provided on the surface of the treatment part 2b contains a high hardness material, so that the electrode body 2 having a lower hardness is damaged than the case where the electrode body 2 having a lower hardness is exposed on the surface. Since it becomes difficult, the surface of the coat layer 3 can be kept smooth, and such sticking of the living tissue can be suppressed.
Thereby, degradation of treatment performance due to fixation of living tissue can be suppressed.

On the other hand, when a coating film made of only a high hardness material is formed on the treatment portion 2b, the impedance of the electrode portion 1 increases and the power of the high-frequency power source 5 must be increased. Therefore, the impedance can be set satisfactorily.
For example, if the impedance of the electrode unit 1 is set to be as low as 0.1Ω or more and 1000Ω or less, the power of the high frequency power supply 5 can be suppressed.
For example, the impedance of a conventional electrode coated with an organic material such as PTFE or silicone resin is 200 to 400 kΩ. When the tissue is coagulated with such an electrode, a power supply of about 80 W is required in the coagulation mode. However, by setting the impedance of the electrode unit 1 to 0.1Ω to 1 kΩ as in the present invention, the same treatment can be performed with a power of about 20 W.
For this reason, compared with the high frequency treatment tool which requires more electric power, handling of the high frequency treatment tool 10 becomes easy, and operativity improves. In addition, the size of the high-frequency power source 5 can be reduced.

  In addition, the conductive material having a high electrical conductivity often has inferior hardness compared to the high-hardness material. However, in the present embodiment, since the high-hardness material and the conductive material are mixed in the coat layer 3, the coat layer By adjusting the degree of dispersion so that the adjacent distance of the high hardness material exposed on the surface of 3 is sufficiently small, the hardness of the coat layer 3 as a whole is improved and the coat layer 3 is hardly damaged. be able to.

  In the above description, an example in which the medical device electrode is used in a high-frequency treatment tool that is an example of a medical treatment tool has been described. However, the medical treatment tool is not limited to a high-frequency treatment tool. For example, any shape such as a probe, forceps, tweezers, scalpel, snare, and wire can be used, and any of bipolar and monopolar can be applied.

1 Electrode part (Electrode for medical equipment)
2 Electrode body 2b Treatment section 3 Coat layer 5 High frequency power supply 10 High frequency treatment instrument (medical treatment instrument)

Claims (4)

A medical device electrode used in contact with an object to be treated,
An electrode body made of a metal material;
Two types each including one or more types of high-hardness materials having higher Vickers hardness than the metal material of the electrode body and one or more types of conductive materials having higher electrical conductivity than the metal material of the electrode body A medical device electrode comprising: a coating layer formed on the surface of the electrode body by mixing the above materials. The electrode body is made of stainless steel,
The hard material is one or more of chromium (Cr), DLC (diamond like carbon), chromium nitride (CrN), titanium nitride (TiN), titanium aluminum nitride (TiAlN), and titanium carbonitride (TiCN). The medical device electrode according to claim 1, comprising: The electrode body is made of stainless steel,
3. The conductive material according to claim 1, wherein the conductive material includes one or more of copper (Cu), gold (Au), aluminum (Al), platinum (Pt), and chromium (Cr). The electrode for medical equipment as described.   The medical treatment tool provided with the electrode for medical devices in any one of Claims 1-3.

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