JP4304307B2 - Medical instruments - Google Patents

Description

  The present invention relates to a medical instrument used when performing an operation while observing an affected part electronically imaged.

  In recent years, there are many cases in which surgery is performed while observing the affected area electronically imaged by an electronic imaging device such as MRI or X-ray CT (hereinafter, mainly described as "MRI device"). It has become. That is, these imaging devices can accurately display a fine image of a living tissue that is a surgical site, and are thus becoming an extremely important auxiliary means during surgery.

  However, a medical instrument made of a ferromagnetic metal material such as stainless steel (hereinafter referred to as “surgical knife” as a representative example) has a risk of being attracted to an MRI magnet due to its magnetism. MRI image distortion is likely to occur due to disturbance of the magnetic field due to eddy currents induced by waves. In addition, when X-ray CT is used, the shadow of a metal knife overlaps the affected area image and obstructs observation.

Patent Document 1 discloses a medical device (scalpel, biopsy needle, etc.) that matches the magnetic susceptibility of the human body by doping a composite material composed of carbon fiber and polymer with a small amount of iron oxide (ceramic material). is suggesting. This medical instrument is supposed to give a good image without distortion. However, when the composite material doped with ceramic proposed in this document is used as, for example, a scalpel, there is a problem that observation of an affected area is hindered because X-rays are not transmitted. Furthermore, the knife edge of the knife is composed of a dispersed hard ceramic and a soft composite material that holds it, and since a sharp edge cannot be formed, the sharpness from the initial stage of use is low, and the sharpness is further lowered with the passage of time. Therefore, the function required for the medical instrument is not sufficiently achieved.
Japanese Patent Laid-Open No. 10-14924

  Therefore, the present invention is a medical instrument used for performing an operation while observing an affected part imaged electronically, and does not deteriorate image quality and continuously exhibits good characteristics. The main purpose is to provide a medical device to be obtained.

  As a result of intensive studies to solve the above problems, the present inventor can achieve the object when a coating layer made of a nonmagnetic metal material is formed on a carbonaceous material substrate. I found.

That is, the present invention provides the following medical instruments.
1. A medical instrument used for performing an operation while observing an affected part imaged electronically, wherein the medical instrument is provided with a nonmagnetic material coating layer on the surface of a carbonaceous material substrate.
2. Item 2. The medical device according to Item 1, wherein the carbonaceous material base material comprises at least one selected from a carbon fiber reinforced composite material, graphite, and glassy carbon.
3. Item 2. The medical device according to Item 1, wherein the nonmagnetic material coating layer is made of a nonmagnetic metal material.
4). Item 4. The medical instrument according to Item 3, wherein the nonmagnetic metal coating layer is formed by at least one method selected from an electrolytic plating method or an electroless plating method.
5. Item 5. The medical device according to Item 4, wherein the non-magnetic metal material is a Ni-P alloy and / or a Ni-P alloy in which ceramic particles are dispersed.
6). Item 6. The medical instrument according to Item 5, wherein the nonmagnetic metal material is a Ni-P alloy.
7). Item 7. The medical device according to Item 6, wherein the content of P in the Ni-P alloy is 8 to 15 wt%.
8). Item 8. The medical device according to any one of Items 1 to 7, wherein a soft nonmagnetic metal intermediate layer is formed between the carbonaceous material and the nonmagnetic metal coating layer.
9. Item 9. The medical instrument according to any one of Items 1 to 8, wherein the medical instrument is a surgical instrument.
10. Item 10. The medical instrument according to Item 9, wherein the surgical tool is a blade.
11. Item 11. The medical instrument according to Item 10, wherein the blade is a knife, a lancet or a scissor.
12 The blade part which consists of a nonmagnetic metal coating layer is provided in the single side | surface side of a cutter, and the stress relaxation layer which consists of a soft nonmagnetic metal coating layer is provided in the opposite surface in any one of said claim | item 9-11. Medical instruments.

According to the present invention, the following effects are achieved.
Medical instruments that do not interfere with the creation of electronic images of biological tissues by MRI, X-ray CT, etc. can be obtained.

In particular, in a composite electronic imaging apparatus using MRI and X-ray CT in combination, the MRI microwave and X-ray transmission are not inhibited, so that a remarkable effect is exhibited.
The surgical knife according to the present invention is excellent in sharpness as a cutting edge because the hardness of the hard non-magnetic material forming the coating layer on the substrate is high.

  In addition, when the sharpness is reduced due to wear of the cutting edge portion, it is possible to return to the same sharpness as the original by performing sharpening.

  Since the heat resistance of not only the coating layer but also the base material is high, autoclaving can be performed at a high temperature.

  Hereinafter, the medical device according to the present invention will be described in more detail with reference to cross-sectional views schematically showing typical embodiments of the present invention.

  FIG. 1 is a side view schematically showing a typical embodiment of a medical knife according to the present invention.

  FIG. 1- (a) shows a first embodiment in which a coating layer made of a hard nonmagnetic metal material is provided on one side of a base material made of a carbonaceous material.

  As the carbonaceous material constituting the substrate, a known carbon fiber reinforced composite material, graphite, glassy carbon, or the like can be used. These materials are (1) non-magnetic, (2) resistant to autoclaving at 120 ° C or higher, which is performed for sterilization of medical instruments, and do not melt or deform. (3) MRI microwaves It is suitable as a substrate in that it does not inhibit, and (4) it has excellent X-ray permeability.

The carbon fiber reinforced composite material is not particularly limited, but (1) a plurality of sheets of carbon fibers arranged in one direction are laminated to each other so that the fiber directions are orthogonal to each other, and a pitch or resin is used. Material obtained by impregnation and firing, (2) Material obtained by laminating a plurality of carbon fiber woven sheet bodies and impregnating with pitch or resin, and firing, (3) Pitch on carbon fiber nonwoven fabric Or a material obtained by impregnating a resin and then firing, (3) a material obtained by impregnating a felt-like carbon fiber with a pitch or resin and then firing the material. Prior to forming the nonmagnetic material coating layer described later, the base material may be processed in advance into a shape substantially corresponding to a predetermined product shape. Or after forming a nonmagnetic material coating layer on a base material, you may process into a predetermined product shape.
Similarly, when graphite or glassy carbon is used as the base material, it is processed in advance into a shape substantially corresponding to a predetermined product shape prior to forming the hard nonmagnetic metal material coating layer.
As the carbonaceous material base material, a carbon fiber reinforced composite material is more preferable for reasons such as excellent toughness and adhesion to the coating layer.

  In the medical knife shown in FIG. 1- (a), a hard nonmagnetic metal material coating layer serving as a blade portion is directly formed on a required portion on a base material. The tip of the coating layer functions as a cutting edge.

  Hard non-magnetic metal materials include Ni-P alloys (P content = about 8-15% by weight, more preferably about 10-12% by weight), Ni-WP alloys (W content = about 10-50% by weight) And more preferably about 20 to 30% by weight: P content = about 8 to 15% by weight, more preferably about 10 to 12% by weight). The Ni-W-P alloy containing W together exhibits better wear resistance than the Ni-P alloy. The Ni-P alloy is non-magnetic when the P content is in the range of 8 to 15% by weight, and exhibits high hardness (about Hv = 500 to 1000) and good toughness.

  Formation of the coating layer on the substrate made of the carbonaceous material can be performed by a known electrolytic plating method or electroless plating method. Furthermore, for example, after electroless plating is performed on the substrate according to a conventional method, electroplating can also be performed.

The conditions for forming the coating layer by these methods may be appropriately selected according to the shape and type of the medical device, the type of the base material, the type of the hard nonmagnetic metal material, and the like. The surface cleaning, surface roughening, and application of a catalyst metal that are usually performed prior to the plating operation may be performed according to conventional methods.
The hard nonmagnetic metal material coating layer may be formed as a composite plating layer in which hard material fine particles such as TiO2, SiC, Al2O3, ZrO2, WC, and diamond are dispersed in the Ni-P alloy. The composite plating layer can be easily formed by using a plating bath in which hard material fine particles are dispersed in a basic plating bath according to a conventional method. When a composite plating layer is used, durability as a medical instrument, sharpness, etc. can be improved.

  The thickness and width of the hard non-magnetic metal coating layer are not particularly limited as long as they do not interfere with image formation by MRI or X-ray CT, taking into consideration the sharpness, durability, number of reshaping, formation cost, etc. as a medical knife However, the width is usually about 5 to 30 μm and the width is about 3 to 5 mm. If the coating layer is too thin, it will be difficult to form the cutting edge by polishing, whereas if it is too thick, the MRI microwave or X-ray will be blocked and a shadow of the knife will be formed. Sometimes. When the width of the coating layer is too narrow, the number of re-sharpening is reduced, and when it is too wide, the penumbra portion becomes large and inconvenience is caused. When the thickness and width of the coating layer are properly selected, MRI microwaves or X-rays partially penetrate the coating layer, so that the contour of the cutting edge in contact with the affected area can be recognized on the monitor, which is preferable. It is.

  The medical knife of the form shown in FIG. 1- (a) is processed in such a manner that a part of the surface of the base material has a shape corresponding to a predetermined blade part, and then the remaining surface part is masked. By carrying out, it is preferable to produce the coating layer only on the surface of the processed part.

  Next, a surgical knife having a predetermined shape is obtained by sharpening an intermediate product provided with a coating layer at a predetermined position on the surface of the substrate.

  Note that the surgical knife according to the present invention may have an integral structure, or may have a separate structure in which a substantial knife part is attached to a gripping part. In the latter case, the gripped part familiar to the hand can be used for a long time by appropriately replacing the damaged or deteriorated female part.

  FIG. 1- (b) shows a second embodiment in which a coating layer made of a hard nonmagnetic metal material is provided on one side of a base material made of a carbonaceous material via an intermediate layer made of a flexible nonmagnetic metal. Show.

Examples of the flexible nonmagnetic metal that forms the intermediate layer include Cu, Zn, Sn, and Pd that are excellent in adhesion to the base material and the coating layer. The intermediate layer not only improves the adhesion between the base material and the hard non-magnetic metal material, but also exhibits a stress distribution function of the cutting edge.
The intermediate layer made of a flexible nonmagnetic metal can also be formed by a known wet plating method. The thickness of the intermediate layer is not particularly limited as long as it achieves its function, but it is usually preferably about 1 μm or less in order to allow partial transmission of MRI microwaves and X-rays. .

Further, as a modified example (third embodiment) of the embodiment shown in FIG. 1- (b), a second layer is formed on the surface opposite to the intermediate layer (inner side) with a coating layer made of a hard nonmagnetic metal material interposed therebetween. An outermost layer made of a flexible nonmagnetic metal can be provided. The outermost layer exhibits a function of dispersing the stress of the cutting edge. As the flexible non-magnetic metal forming the outermost layer, the same metal as that forming the intermediate layer can be used. The thickness of the outermost layer is not particularly limited as long as the function is achieved, but it is usually about 1 μm. The outermost layer located on the outer surface of the coating layer made of a hard nonmagnetic metal material can also be formed by a known wet plating method.
From the intermediate product obtained by the second embodiment or the third embodiment, a surgical knife having a predetermined shape can be obtained by finally sharpening the cutting edge.

The technique of the present invention enables smooth accurate observation of an affected area using an electronic imaging apparatus such as MRI or X-ray CT, and is not limited to the illustrated knife, and various other medical instruments It can also be applied to.
In particular, a remarkable effect is exhibited in a composite electronic imaging apparatus using both MRI and X-ray CT.

Examples will be shown below to further clarify the features of the present invention.
[Example 1]
Commercially available carbon fiber reinforced composite material (obtained by repeatedly pressing and laminating a plurality of phenol resin impregnated sheet bodies in which carbon fibers are arranged in the same direction so that the fiber directions are orthogonal to each other, and then repeating pitch impregnation and firing. Material: Bulk density 1.61 g / cm ³ , bending strength 95 MPa, thickness 2 mm) was cut into a long piece of 10 mm × 50 mm and used as a substrate.
This base material (including stannous chloride and palladium chloride) was dipped in a solution diluted to 40 ml / l with distilled water (produced by Okuno Pharmaceutical Co., Ltd.), then treated with sulfuric acid, and then commercially available. Ni-P alloy plating bath (manufactured by Sakakibara Eugelite Co., Ltd.) is used to perform electroless plating at a temperature of 90 ° C., so that a Ni-P alloy plating coating layer with a film thickness of 20 to 25 μm (P content = 10 weight) %) Was formed. Note that one side of the base material was previously masked with a tape so that a coating layer was formed on the other side.
Next, the cutting edge was sharpened to the shape shown in FIG. 1- (a) to create a test knife (cutting edge angle = about 10 degrees).
[Test Example 1]
When the test knife obtained in Example 1 was attached to the chest of the subject and then X-ray irradiation was performed, the outline of the knife edge was observed on the X-ray image. The shadow of the base material part was not recognized. Therefore, when performing an operation while observing an electronic image using the scalpel according to the present invention, the position of the scalpel blade edge is clearly shown, but an obstacle to the operation due to the shadow of the scalpel base part It is presumed that will not occur.
[Test Example 2]
After the test scalpel obtained in Example 1 was attached to the subject's forehead, the MRI image of the head was observed. As a result, no distortion of the image was observed and the scalpel contour was shown clearly. A tomographic image was obtained. From this, it is presumed that when the operation is performed while observing the MRI image using the surgical scalpel according to the present invention, there is no obstacle to the operation due to the shadow of the scalpel.
[Test Example 3]
Using a normal surgical scalpel and a test scalpel obtained in Example 1, chicken thigh and pork fillet were cut in a direction perpendicular to the muscle tissue.

  In either case, there was no difference in sharpness and cut appearance. From this, it is estimated that the surgical knife according to the present invention exhibits the same function as an existing surgical knife.

1 is a side view showing an overview of an embodiment of a test surgical scalpel according to the present invention. FIG.

Claims (7)

A surgical blade used for performing an operation while observing an affected area electronically imaged, and comprising nonmagnetic carbon made of at least one selected from a carbon fiber reinforced composite material, graphite, and glassy carbon A non-magnetic metal coating layer made of a non-magnetic metal material is provided on the surface of the base material with a thickness of 5 to 30 μm, and the non-magnetic metal material disperses Ni-P alloy and / or ceramic particles. Surgical blade made of P alloy. The surgical blade according to claim 1, wherein the nonmagnetic metal coating layer is formed by at least one method selected from an electrolytic plating method and an electroless plating method. The surgical blade according to claim 1 or 2, wherein the non-magnetic metal material is made of a Ni-P alloy. The surgical blade according to claim 3, wherein the content of P in the Ni-P alloy is 8 to 15 wt%. The surgical blade according to claim 1, soft magnetic metal intermediate layer is formed between the carbonaceous material substrate and a non-magnetic metal coating layer. The surgical blade according to any one of claims 1 to 5, wherein the blade is a knife, lancet, or scissors. The blade part which consists of a nonmagnetic metal coating layer is provided in the single side | surface side of a cutter, and the stress relaxation layer which consists of a soft nonmagnetic metal coating layer is provided in the opposite surface. Surgical tools.

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