JP2003250891A - Medical ceramic-coated needle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a medical ceramic-coated needle not producing any broken state during its use and not applying any bad influence against a sampled tissue piece and a cell around a piercing needle pierced at a lesion part. <P>SOLUTION: An insulating ceramic coating with a resistivity ρ of 10<SP>5</SP>Ω.m or more is formed at a part of or on the entire surface of an outer surface of a metallic needle and over an inside part of at least 1 mm from the extremity end of the needle at the inner surface. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical ceramic-coated needle suitable for use mainly as an injection needle or a puncture needle for liver biopsy / renal biopsy. And
The medical ceramic-coated needle of the present invention completely eliminates the adverse effects on living tissues and cells, which have been a concern in the past when used.

[0002]

2. Description of the Related Art Recent advances in medical technology have been remarkable. For example, in the examination of the liver, pancreas, etc., in order to obtain data that cannot be obtained by a blood test of a patient, ultrasonic examination using an echo or CT ( Computed tomography) examination, M that projects cross-sectional images of various organs using strong magnetism and radio waves
An RI (magnetic resonance imaging) examination, an angiography examination in which a contrast agent is injected through a thin tube (catheter) to image the state of blood vessels, and the like are widely used.

Although the presence of lesions such as cancer can be diagnosed by these blood tests and various image diagnoses, a histopathological examination of a lesion site by a liver biopsy or the like is required for definitive diagnosis. Usually, in such an examination, a method in which a special puncture needle is directly pierced into the lesion site to collect a tissue piece is adopted.

However, when the current puncture needle is used, since the base material of the needle is a conductive metal (resistivity ρ: 10 ⁻⁶ to 10 ⁻⁸ Ω · m) having excellent electrical characteristics, the lesion site It has been pointed out that it has an adverse effect on the tissue pieces collected from the tissue and cells around the puncture needle that punctures the lesion.

In this respect, if a ceramic puncture needle (hereinafter simply referred to as a ceramic puncture needle or a ceramic needle) is used, it does not adversely affect the collected tissue pieces or cells around the puncture needle punctured in a lesion. it is conceivable that. However, since ceramic puncture needles and ceramic needles are very fragile and easily broken, they are not used at all at present.

As a solution to the above problem, the inventors have previously stated that "a part or all of the surface of a metal needle,
A medical-use ceramic-coated needle characterized by having an insulating ceramic coating having a resistivity ρ of 10 ⁵ Ω · m or more ”was disclosed in Japanese Patent Application No. 2002-12863. With the development of the above technology, it has become possible to collect a piece of tissue without causing breakage during use and without adversely affecting the cells around the puncture needle that has punctured the lesion. .

[0007] In developing the above-mentioned invention, the inventors firstly used a normal metal puncture needle as a puncture needle that does not adversely affect cells around the puncture needle punctured in the collected tissue piece or lesion. It was considered to deposit a ceramic film on the surface of the needle. However, even if a ceramic film is formed on the surface of an extremely thin cylinder such as a puncture needle, if the adhesion is poor, the ceramic film will peel off during use, and the intended purpose cannot be achieved. In particular, since the puncture needle and the injection needle are inevitably bent to some extent during use, the risk of peeling is extremely great.

For example, Japanese Examined Patent Publication No. 6-20464 proposes a medical incision / press-fitting instrument in which the surface of a medical knife is coated with a diamond film to reduce the frictional resistance at the time of incision. However, the above-mentioned diamond film is formed by heating the substrate to 500 to 1300 ° C., and since the difference in thermal expansion between the substrate and the diamond film is large, there is a problem that the diamond film easily peels off, It cannot be applied to a puncture needle or the like targeted by the present invention.

By the way, recently, when a thin TiN ceramic film was plasma-coated on a ferritic stainless steel plate by the present inventors and then plastic working was performed by 180 ° bending deformation, the TiN ceramic film was cracked at a crack generation position. A new fact has been clarified that it has a unique concave shape like metal and exhibits local elongation. [Seio Iguchi: Refer to the 2001 International Photo Exhibition award-winning works (Indianapolis, USA, 2001/11 / 5-8. jointly IMS (International M
etallographic Society) and ASM (American Society of
Metals)]. This phenomenon suggests that the ceramic film, which is considered to be very brittle, also undergoes elongation in plastic working similarly to metal, and can be processed.

Therefore, the inventors immediately tried to form a TiN ceramic film on the surface of a puncture needle made of stainless steel by using the above-mentioned ceramic coating method in a high vacuum / high plasma atmosphere. As a result, it was confirmed that the obtained TiN ceramic film had extremely good adhesion to the puncture needle and that peeling did not occur even if it was bent a little.

However, when the puncture needle coated with this TiN ceramic film is used, the tissue around the tissue and the cells around the puncture needle punctured in the lesion are adversely affected, though not as much as the conventional metal puncture needle. Could not be completely wiped out.

[0012] Therefore, as a result of extensive studies to solve this point, any ceramic may be used as the coating ceramic as long as it is an insulating material having a large resistivity ρ. Was clarified.
Thus, the inventors of the present invention disclosed in Japanese Patent Application No. 2002-12863, "provide an insulating ceramic coating having a resistivity ρ of 10 ⁵ Ωm or more on part or all of the surface of a metal needle. It has been developed as a "medical ceramic coated needle".

According to the above invention, the adhesion between the finely processed metal needle and the ceramic thin film having an insulating property is strengthened by adopting the ceramic coating method in a high vacuum / high plasma atmosphere. is there. That is,
The above invention is characterized in that a composite structure (including a gradient functionality) is formed through a mixed layer of an iron matrix and a ceramic film, and the respective properties are skillfully utilized.

[0014]

However, even when the above-mentioned ceramic-coated puncture needle is used, the collected tissue piece may be adversely affected. That is,
Since the outer surface of the puncture needle is coated with an insulating ceramic, the cells around the puncture needle punctured in the lesion were not damaged at all, but the inside of the puncture needle was Since it is not always covered with such an insulating ceramic, when the amount of collected tissue piece is large, such tissue piece contacts the metal surface,
In some cases, it had an adverse effect.

The present invention relates to an improvement of the technique disclosed in the above-mentioned Japanese Patent Application No. 2002-12863, in which an insulating ceramic is surely provided on the inner surface of the puncture needle, at least in the region where a tissue piece is sampled. We propose a ground-breaking ceramic-coated needle for medical use that is coated to prevent any adverse effect on the collected tissue pieces, let alone the cells around the puncture needle that has punctured the lesion. The purpose is to

[0016]

That is, the gist of the present invention is as follows. 1. A medical device characterized by having an insulating ceramic coating with a resistivity ρ of 10 ⁵ Ω · m or more over part or all of the outer surface of the metal needle and at least 1 mm from the needle tip on the inner surface. Ceramic coated needle.

2. In 1, the ceramic coated needle for medical use, wherein the thickness of the ceramic coating is 0.05 to 5.0 μm.

3. 1. The medical ceramic-coated needle according to 1 or 2 above, wherein the ceramic coating is made of at least one selected from Al, B and Si nitrides, carbides or oxides.

4. In the above 1, 2 or 3, a medical ceramic-coated needle, wherein the base metal of the needle is stainless steel.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below. FIG. 1 schematically shows a magnetron sputtering apparatus suitable for manufacturing the ceramic-coated needle of the present invention. In addition, Fig. 2 (a) shows the installation form of the metallic puncture needle, which is the material.
FIG. 2 (b) shows an enlarged cross-section of the tip of the puncture needle after coating the ceramic film. In the figure, number 1 is a vacuum chamber, 2 is a sample holder, and 3 is a metal puncture needle. Further, 4 is ferrosilicon which is a target, 5 is a magnet, 6 is a copper plate interposed therebetween, and 7 is its water cooling tube.
Further, 8 is a reaction gas inlet, 9 is ionized Si particles, 10 is a jig for fixing the puncture needle 3, and 11 and 12 are puncture needles 3.
The ceramic film is formed on the outer surface and the inner surface of the ceramic film, respectively.

As shown in FIG. 1, the ionized Si particles 9 react with nitrogen gas, which is a reaction gas, while moving straight on the metal puncture needle 3 fixed by the sample holder 2 to produce SiN _x. It will be vapor-deposited on the surface of the puncture needle 3.

In the present invention, when depositing the above-mentioned vapor-deposited particles, that is, SiN _X ceramics, the puncture needle 3 is vapor-deposited in parallel with the traveling direction of the vapor-deposited particles and at the tip of the puncture needle 3. The feature is that it is installed facing the particles. With such a configuration, the vapor deposition particles effectively penetrate and adhere to the inside of the puncture needle 3, and as shown in FIG. 2 (b), not only the outer surface but also the inner surface is insulated. The effective ceramic membrane 12 is effectively coated.

The coating of the ceramic film on the outer surface of the puncture needle does not necessarily have to be applied to the entire surface of the needle, as long as it covers at least the region that comes into contact with the living tissue during its use. In this respect, the inner surface of the puncture needle is the same, and it is necessary to cover at least 1 mm from the tip of the needle (the root of the opening) to the inside (the area indicated by h in Fig. 2 (b)) with a ceramic film. . This is because the inner surface of the puncture needle may be adversely affected on the collected tissue piece unless the insulating ceramic film covers at least 1 mm inside. It is preferable to coat the ceramic film from the tip of the needle (the root of the opening) to about 3 to 10 mm inside.

Further, in the present invention, since the surface of the needle is coated with ceramics, any material can be used as the base material of the needle, but stainless steel is particularly preferred. This is because the surface of stainless steel does not rust and is easily processed by precision processing, and ferritic stainless steel is particularly suitable.

For example, when a puncture needle substrate is made of stainless steel, a stainless steel material is continuously cast,
After performing hot rolling-cold rolling-brightness annealing, precision processing is performed to form various needle shapes having an outer diameter of 0.05 to 2.5 mm and a length of 100 to 250 mm according to the purpose. The processing steps at this time may be performed according to the conventional technique.

Then, the surface of the obtained needle is cleaned by ultrasonic cleaning, electrolytic polishing, etc., and then the ceramic film is formed as described above. It is important to use insulating ceramics with a ratio ρ of 10 ⁵ Ω · m or more. This is because a ceramic having a resistivity ρ of less than 10 ⁵ Ω · m cannot completely eliminate the adverse effect on the collected tissue pieces and cells around the puncture needle that has punctured the lesion.

FIG. 3 shows the results of examining the effect on living tissue when using a puncture needle in which a ceramic film having a different resistivity ρ on the surface of a stainless steel substrate is used. Damage degree (TDD: Texture Damage D
egree; pathological examination by microscopic observation). If the TDD is 0.40 or less, preferably 0.35 or less, it can be said that there is no adverse effect on the living tissue.
As shown in the figure, by using a ceramic with a resistivity ρ of 10 ⁵ Ω · m or more as the coating ceramic,
It was possible to obtain a good result of 0.40 or less. In the figure, those with a resistivity ρ of 7 × 10 ⁻⁶ are stainless steel puncture needles without a ceramic coating, and those with a resistivity ρ of 3 × 10 ⁴ are puncture needles coated with TiN as a ceramic. .

Here, as the ceramic having a resistivity ρ of 10 ⁵ Ω · m or more, at least one selected from Al, B and Si nitrides, carbides or oxides is advantageously suitable. The coating thickness of the ceramic film is preferably 0.05 to 5.0 μm. This is because it is difficult to secure sufficient insulation if the ceramic film thickness is less than 0.05 μm, while the ceramic film thickness is 5.0 μm.
If it exceeds, not only it becomes difficult to secure the adhesion between the ceramic film and the matrix, but also the cost increases due to the coating.

Further, the method for coating the ceramic film as described above is not particularly limited, but it is advantageous to coat it by the dry plating method.
As such a dry plating method, application of a magnetron sputtering method capable of high ionization and high-speed film formation is most suitable, but other known methods such as RF (Radio Frequency), hollow cathode discharge method, and arc discharge method are also known. A PVD coating method, a CVD coating method, or a high plasma CVD coating method can also be used. For example, when using a ferrosilicon target to perform SiN _X coating, input power: 5 to 10 kW
, Degree of vacuum: 0.8 × 10 ^{-4 to} 3 × 10 ^-3 Torr, Ar gas: 50 to 5
00 sccm, N ₂ gas: 50 to 500 sccm is the optimum condition.

The needle used in the present invention is not limited to the above-mentioned puncture needle and injection needle, and any hollow medical needle such as a contrast needle for injecting a contrast medium can be used as a medical needle. Momo fits.

[0031]

Examples Example 1 a) C: 0.03 mass%, Si: 0.2 mass%, Mn: 0.15 mass
%, P: 0.010 mass%, S: 0.010 mass% and Cr: 18.
Ferritic stainless steel containing 8 mass% and the balance being Fe and inevitable impurities, and b) C: 0.05.
mass%, Si: 0.3mass%, Mn: 0.20mass%, P: 0.012 m
ass%, S: 0.011 mass%, Cr: 19.1 mass%, Ni: 9.1 m
Ass and Mo: 0.25mass%, with the balance being Fe and unavoidable impurities in composition of austenitic stainless steel, respectively, after continuous casting, after hot rolling-cold rolling-bright annealing By precision machining, outer diameter: 0.8 m
A contrast needle having a length of m and a length of 200 mm was prepared. Then, after ultrasonically cleaning these contrasting needles, SiN _X was applied in a high plasma atmosphere using the magnetron sputtering apparatus shown in FIG.
Was deposited. When depositing the SiN _X ceramic film by this magnetron sputtering method, Ar: 100 scc
m, N ₂ : A film having a thickness of 0.8 μm was formed in 65 sccm. Also, SiN _X
The coating area of the ceramic membrane was 70 mm from the tip of the needle for the outer surface and 6 mm from the tip of the needle (root of the opening) for the inner surface.

The tissue damage degree (TDD) and SiN of the tissue collected by using the thus obtained ceramic-coated contrast enhancement needle
Table 1 shows the results of examining the adhesion of the _X ceramic film. Here, regarding the adhesion of the ceramic film, the ceramic-coated steel plate, on which the ceramic film was formed by the same method, was wound around the surface of the separately prepared stainless steel plate, and the film peeling did not occur. The minimum diameter was evaluated. In addition,
For comparison, Table 1 also shows the results of the investigation when the ferritic stainless steel contrast needle of the above a) without the coating of the ceramic film was used.

[0033]

[Table 1]

As shown in the table, the ceramic-coated needles obtained according to the present invention had good coating adhesion, and the TDD of the sampled tissue was an excellent value of 0.15 or less.

Example 2 C: 0.03 mass%, Si: 0.3 mass%, Mn: 0.12 mass%,
P: 0.011 mass%, S: 0.009 mass% and Cr: 16.9ma
A ferritic stainless steel material containing ss% and the balance of Fe and inevitable impurities is continuously cast, followed by hot rolling-cold rolling-bright annealing, followed by precision machining to obtain an outer diameter: A biopsy needle under ultrasound imaging with a length of 2.1 mm and a length of 170 mm was prepared. Next, after ultrasonically cleaning the biopsy needle, various ceramic films shown in Table 2 were formed in a high plasma atmosphere by using a magnetron sputtering method (a part of the RF method was also used). At this time, the installation state of the biopsy needle is shown in FIG.
The same as in. Table 2 also shows the results of examining the tissue damage degree (TDD) of the tissue collected using the ceramic-coated needle thus obtained and the adhesion of the coated ceramic film.

[0036]

[Table 2]

As shown in the table, when the insulating ceramic film having the resistivity ρ of 10 ⁵ Ω · m or more is formed according to the present invention, the TDD of the sampled tissue can be reduced to 0.35 or less. Therefore, it can be seen that the adverse effect on the collected tissue piece can be completely wiped off, not to mention the cells around the puncture needle that has punctured the lesion in its use.

[0038]

As described above, according to the present invention, there is no breakage during use, and there is no adverse effect on the collected tissue pieces or cells around the puncture needle puncturing the lesion. The ceramic-coated needle for use can be stably obtained.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a magnetron sputtering apparatus suitable for use in manufacturing the ceramic-coated needle of the present invention.

FIG. 2 (a) is a diagram showing an installation form of a puncture needle with respect to a sample holder, and FIG. 2 (b) is an enlarged cross-sectional view of a tip portion of the puncture needle.

FIG. 3 Resistivity ρ of coated ceramics and degree of tissue damage (T
It is the figure which showed the relationship with DD).

[Explanation of symbols]

1 vacuum tank 2 Sample holder 3 Metal puncture needle 4 Ferrosilicon target 5 magnets 6 Copper plate 7 water cooling tube 8 Reactant gas inlet 9 Ionized Si particles 10 Fixing jig for puncture needle 11 Ceramic membrane coated on outer surface of puncture needle 12 Ceramic membrane coated on inner surface of puncture needle

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masaaki Ehara             Chiba Prefecture Chiba City Chuo-ku 1-8-1 Chiba, Chiba             Inside the university F-term (reference) 4C066 AA07 AA09 BB01 CC01 DD08                       FF04 FF05 KK04

Claims (4)

[Claims] 1. An insulating ceramic coating having a resistivity ρ of 10 ⁵ Ω · m or more is formed on a part or the whole outer surface of a metal needle and at least 1 mm from the needle tip of the inner surface. Characteristic ceramic coated needle. 2. The medical ceramic-coated needle according to claim 1, wherein the ceramic coating has a thickness of 0.05 to 5.0 μm. 3. The medical ceramic-coated needle according to claim 1, wherein the ceramic coating comprises at least one selected from Al, B and Si nitrides, carbides or oxides. 4. The medical ceramic-coated needle according to claim 1, 2 or 3, wherein the base metal of the needle is stainless steel.