JPH06189965A - Medical instrument - Google Patents

Abstract

PURPOSE:To realize the small diameter of a medical instrument by slidably inserting a metal wire in a guide tube and fitting a functional member of the predetermined diameter to the end of the wire, regarding a medical instrument to be inserted in a body for sampling a part of an organism tissue or removing an obstruction such as a thrombus. CONSTITUTION:This medical instrument A is constituted of a guide tube 1 to be inserted in a hole drilled through an endscope, a wire of stainless steel or the like to be inserted in the tube 1, and a functional member B fitted the end of the wire 2. The forward end of the guide tube 1 is used as a housing section 1a for the member B, and a coil 3 is buried in the housing section 1a, thereby applying spring quality to the section 1a. Also, the member B is so formed as to have length shorter than the maximum diameter of the wire 2, and equal to or less than ten times of the maximum outer diameter of the wire 2. When the member B is used for sampling a part of an organism tissue, a spine-like section is formed on the external surface thereof. Also, when the member B is used for removing or drilling a thrombus or the like, a spiral cutting edge is formed on the external surface thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical device which is inserted into a body to collect a part of a living tissue or remove an obstruction such as a thrombus.

[0002]

2. Description of the Related Art There are medical devices for collecting a part of a living tissue to carry out a tissue culture test, and medical devices for destroying a thrombus formed in a blood vessel and circulating blood. Such medical instruments are endoscopes or catheters (hereinafter referred to as "treatment instruments").
It is inserted into the through hole formed in the, and is sent to the affected area together with the endoscope and operated.

A medical device for collecting a part of a living tissue has a tweezer-shaped sampling tool provided at the tip of a wire-shaped operating tool, and the sampling tool is inserted into a through hole of an endoscope. It is configured to reach a diseased part together with an endoscope, and then a practitioner operates an operation part at hand to drive a sampling tool to collect a part of a biological tissue.

As a medical device for removing thrombus and the like, there is a technique disclosed in JP-A-4-114641. In this technique, a plurality of operators are provided at the tip of the wire and cemented carbide particles such as diamond abrasive particles are fixed to the operators to form a drill, and the thrombus is crushed by driving the drill with a motor. To be removed. Also recently
There is also a structure in which a thin metal wire is formed into a spiral shape and the wire is inserted into a clogged portion of a blood vessel to remove a thrombus.

[0005]

The medical device for collecting a part of a living tissue by the above-mentioned tweezers-shaped sampling device or the medical device for removing thrombus disclosed in Japanese Patent Laid-Open No. 4-1144641 has a plurality of movable parts. Since it has a portion, the structure becomes complicated and the thickness becomes thick. Therefore, there is a problem in that the endoscope to which these medical devices are attached inevitably has a large outer diameter, and thus the application site for the human body is limited.

Further, in a medical device constructed by spirally forming a thin metal wire, a bending force acts on the metal wire to cause bending or a tensile force acts to cause elongation when removing a thrombus. There is a problem, that is, poor durability. Further, since the cutting amount is small, it may take a long time to restart the blood flow.

On the other hand, the conventional endoscope has a considerably large outer diameter and is mainly used for the digestive system. However, recently, an extremely thin endoscope has been developed and is used for the respiratory system and other parts, and along with this, the medical device attached to the endoscope has a small outer diameter and strength. Those with high prices are required.

An object of the present invention is to provide a medical device having a small outer diameter and high durability.

[0009]

In order to solve the above-mentioned problems, a typical medical device according to the present invention comprises a guide tube formed of a material having flexibility and a surface having a low coefficient of friction. A wire that is inserted into the guide tube and has a guide portion formed in at least a portion thereof having an outer diameter slightly smaller than the inner diameter of the guide tube; Or having a functional member for removing a blockage, and the outer diameter of the functional member is less than or equal to the outer diameter of the guide portion formed on the wire and the length is less than or equal to 10 times the outer diameter of the guide portion. It is a feature.

In the medical device, it is preferable to form a spherical portion at the tip of the functional member.

[0011]

According to the medical device, a functional member having a plurality of barbs or a spiral projection is formed at the tip of a wire having a guide portion having a diameter smaller than the inner diameter of the guide tube at least in part. A functional member is provided, and the outer diameter of the functional member is less than or equal to the outer diameter of the guide portion and less than the outer diameter of the guide portion.
Since the medical device is formed by forming the functional member and the wire into the guide tube with a length of 10 times or less, when the wire is moved back and forth in the axial direction or rotated, the guide portion is guided by the guide tube. The direction of movement can be guided by touching the inner surface of the. Therefore, the functional member provided at the tip of the wire moves as the wire moves, and a part of the biological tissue is collected by the barb formed on the functional member, or the thrombus is formed by the spiral protrusion formed on the functional member. It is possible to remove or occlude blockages such as.

By forming the functional member to have a length equal to or less than the outer diameter of the guide portion and less than or equal to 10 times the outer diameter of the guide portion, the function is achieved when a part of the living tissue is collected or the thrombus is removed. The mechanical strength against bending force acting on the member can be improved.

Further, when a spherical portion is formed at the tip of the functional member, when the functional member is projected from the guide tube and a predetermined work is performed, even if the tip of the functional member comes into contact with a living tissue, a contact portion Will not be damaged.

[0014]

EXAMPLES Examples of the medical device will be described below with reference to the drawings. 1 is a cross-sectional view illustrating the overall configuration of a medical device, FIG. 2 is a side view illustrating the configuration of a functional member, FIG. 3 is a side view of a functional member having a spherical portion at its tip, and FIGS. 4 to 6 are wires. It is a side view explaining the relationship between and a functional member.

The medical device A shown in FIG. 1 is sent together with an endoscope to a diseased part to be treated, and a part of living tissue is sampled in the diseased part, or a blockage such as a thrombus in the affected part is removed. Perforation is performed to resume blood flow. In particular, the medical device A according to the present embodiment has a thin outer diameter and is capable of improving strength, and is a cell of an extremely thin organ such as the ureter, kidney, trachea, bronchial tube, bile duct, pancreatic duct and the like. It is possible to collect a piece or to remove and perforate a thrombus or the like in a coronary artery or the like.

In FIG. 1, a medical device A includes a guide tube 1 which is inserted into a through hole formed in an endoscope (not shown),
The wire 2 is inserted through the guide tube 1, and the functional member B provided at the tip of the wire 2.

The size of the guide tube 1 in the medical device A has an outer diameter slightly smaller than the inner diameter of the through hole of the endoscope corresponding to the endoscope for performing the intended treatment, and It is configured to be sufficiently longer than the length of the endoscope. The dimensions of the wire 2 and the functional member B are set in correspondence with the inner diameter of the guide tube 1. That is, the medical device A has a size corresponding to the size of the endoscope to be applied.

The guide tube 1 is inserted through the through hole of the endoscope and has the wire 2 and the functional member B inserted therein. The guide tube 1 accommodates the functional member B until it reaches the affected area to be treated, and also the functional member. After projecting B and finishing the treatment,
By accommodating the functional member B again, the functional member B is protected from being damaged. The guide tube 1 bends easily with the bending of the endoscope, and after reaching the affected part, it easily bends and retracts from the through hole according to the operation of the practitioner and also bends easily, and the treatment is completed. After that, it is necessary that the functional member B can be housed easily.

Therefore, the guide tube 1 is made of a material having flexibility and at least the surface of which has a low friction coefficient. That is, the guide tube 1 can be made of only a material having flexibility and a low friction coefficient, or can be made by coating the surface of a flexible material with a material having a low friction coefficient. It is possible. In this embodiment, the guide tube 1 is formed by using a tube formed of a fluororesin.

The accommodation portion 1a for accommodating the functional member B, which is the distal end portion of the guide tube 1, has a spring property. That is, a coil spring 3 formed by winding a metal wire in a coil shape is provided in a portion corresponding to the housing portion 1a, and the housing spring 1 is restored by the restoring force of the coil spring 3.
The a is constructed so as to be able to maintain a linear state unless an external force acts.

Therefore, when the guide tube 1 is projected from the endoscope, the accommodating portion 1a maintains the straight state, so that the inner surface of the guide tube 1 does not come into contact with the functional member B and the functional member B is not contacted. It is possible to easily accommodate the functional member B after the projection is performed and a predetermined treatment is performed. In particular, when a part of the living tissue is collected, there is no possibility that the collected tissue cells are brought into contact with the guide tube 1.

At the end of the guide tube 1 on the accommodation portion 1a side, an inner surface is formed with an enlarged portion 1c whose diameter increases from the accommodation portion 1a side toward the opening 1b. By forming the enlarged portion 1c at the end of the guide tube 1 as described above, the functional member B is guided by the guide tube 1 during treatment or when the treatment is completed and the functional member B is accommodated in the guide tube 1. It can be easily accommodated without getting caught.

The wire 2 is inserted through the guide tube 1,
After reaching the affected area to be treated, it has a function of transmitting the operating force by the practitioner and causing the functional member B provided at the distal end to appear or disappear from the guide tube 1 or rotate. For this reason, the maximum outer diameter of the wire 2 is slightly smaller than the inner diameter of the guide tube 1, that is, when the wire 2 is inserted into the guide tube 1, the wire 2 and the inner surface of the tube 1 can be comfortably and rattled. It has a size that can form a gap that allows sliding and rotation in the longitudinal direction.

The wire 2 may be formed so as to have the same diameter over the entire length as shown in FIG. 4 (a), and as shown in FIG. 4 (b), the outer diameter at a predetermined position may be set to the guide tube. The guide part 2a having a size slightly smaller than the inner diameter of 1 may be formed, and the other part may be formed with a size smaller than the guide part 2a.

Whether the wire 2 has the same diameter over the entire length, or whether the guide portion 2a is formed in a part and the other portion is formed thinner than the guide portion 2a corresponds to the entire diameter of the medical device A. This is a problem that should be set appropriately. That is, when the diameter of the medical device A is large, the diameter of the wire 2 is also large.
For this reason, if the wire 2 is formed to have a large diameter over the entire length, the rigidity becomes high, which may cause a difficulty in operability. In such a case, it is preferable to form the guide portion 2a on a part of the wire 2 and thin the other part.

The material forming the wire 2 is not particularly limited. However, it is preferable that the wire is made of metal, which does not adversely affect the human body. In this embodiment,
As the wire 2, a wire obtained by drawing a stainless steel wire into a predetermined diameter (for example, diameter 0.26 mm) is cut into a predetermined length (for example, 1400 mm) and used.

The functional member B is provided at the tip of the wire 2,
It has a function of collecting a part of a living tissue, that is, a cell fragment of the tissue, or removing and perforating a thrombus or the like. When the target treatment is performed, the functional member B projects from the guide tube 1 to collect an affected part or to remove and perforate a thrombus, so that an external force such as a bending force or a shearing force acts on the functional member B. Therefore, the functional member B needs to have a strength that can sufficiently oppose the external force.

The maximum outer diameter of the functional member B is the maximum outer diameter of the wire 2 (the outer diameter of the wire 2 when the wire 2 has the same diameter over the entire length, and the outer diameter of the wire 2 when the guide portion 2a is formed on the wire 2). It is smaller than the outer diameter of the guide portion 2a) and has a length of 10 times or less of the maximum outer diameter of the wire 2. Therefore, the slenderness ratio (ratio of thickness to length) in the functional member B is 1/10 or less, and the mechanical strength against bending force can be improved.

The material for forming the functional member B is not particularly limited. However, it is preferable to use a material that does not have a bad influence on the human body and is advantageous in strength.
In the present embodiment, a material is used in which austenitic stainless steel wire is cold-drawn to elongate the structure into a fiber shape to give strength.

As shown in FIGS. 2 (a) to 2 (c), the functional member B has a different shape according to the purpose of treatment.

The functional member B shown in FIG. 2A is a collection member 4 mainly for collecting a part of a living tissue.
Is configured as. The collecting member 4 has a plurality of independent barbs 4a formed on the outer circumference thereof, and the barbs 4a are adapted to scratch the affected area to collect cell fragments. In addition, the tip of the sampling member 4 is not a sharp tip, so as not to damage the living body,
A blunt, that is, a hemispherical portion or an appropriately rounded hemispherical portion 4b is formed.

The functional member B shown in FIG. 2B is constructed as a removing member 5 mainly for removing and perforating thrombus and the like. A cutting blade 5a which is a spiral projection is formed on the outer periphery of the removing member 5, and the thrombus is removed by the cutting blade 5a by operating the wire 2 to move the removing member 5 back and forth in a straight line. It is configured to be perforated. A hemispherical portion 5b is formed at the tip of the removing member 5 so as not to damage the living body. still,
The removing member 5 in the present embodiment has the same shape as the H file which is a dental root canal treating tool.

The functional member B shown in FIG. 2C is constructed as a perforation member 6 mainly for removing and perforating thrombus and the like. A plurality of spiral projections 6 a are formed on the outer periphery of the perforating member 6. The tip of each protrusion 6a is formed in the shape of a cutting edge, and is configured so that the thrombus can be perforated by operating the wire 2 to rotate the perforation member 6 while reciprocating linearly in the longitudinal direction. A hemispherical portion 6b is formed at the tip of the perforating member 6 so as not to damage the living body. The removing member 6 in this embodiment has the same shape as the K-file which is a dental root canal treating tool.

The hemispherical portions 4b to 6b formed at the tips of the functional members B (4 to 6) are coated with an epoxy resin or another resin that does not adversely affect the human body, such as an affected area or a blood vessel. Care is taken not to pierce and damage. However, since the maximum outer diameter of the functional member B is formed smaller than the maximum outer diameter of the wire 2, the diameter of the shaft portion is further smaller than the maximum outer diameter of the wire 2. For example, the diameter of the shaft part of functional member B is 0.3 mm to 0.5
When it becomes about mm, the hemispherical portion 4b is provided at the tip of the functional member B.
The formation of ~ 6b is not without risk of damaging the human body during treatment.

Therefore, as shown in FIGS. 3A to 3C, at the tip of each functional member B (4 to 6), the diameter is larger than the outer diameter of the guide tube 1 and smaller than the inner diameter of the working channel. It is preferable to provide the spherical portion 7 and coat the spherical portion 7 with an epoxy resin.
As described above, by providing the spherical portion 7 at the tip of each functional member B, it is possible to prevent the living body from being damaged, and when the functional member B is accommodated in the accommodating portion 1a of the guide tube 1, the opening 1b is opened. It can be closed.

Next, the integrated structure of the wire 2 and the functional member B will be described with reference to FIGS. The wire 2 and the functional member B can be manufactured from one stainless steel wire rod by machining or the like, and the wire 2 and the functional member B are different members, and these members are connected by welding or the like. It is also possible to configure.

In FIG. 4A, the functional member B is formed at the tip of the wire 2 having the same diameter over the entire length, and the inner diameter of the guide tube 1 is small and the diameter of the wire 2 must be small. Used in cases. When the diameter of the wire 2 becomes small (about 1 mm or less than 1 mm), the rigidity of the wire 2 becomes low and bending easily occurs, but in the structure shown in the figure, the entire length of the wire 2 is guided by the inner surface of the guide tube 1. It is possible to prevent bending. Therefore, the operability of the functional member B is not impaired.

When the inner diameter of the guide tube 1 is relatively large (about 2 mm or 2 mm or more), the wire 2 has a part of the outer diameter slightly smaller than the inner diameter of the guide tube 1 as shown in FIG. 4 (b). The operability of the functional member B can be improved by forming the guide portion 2a having a diameter and making other portions thinner than the guide portion 2a.

5 (a) and 5 (b), the wire 2 and the functional member B are formed as different members, and these members are butt-welded and connected to each other, and the guide tube 1 having an outer diameter at the connecting portion. It is configured by mounting a pipe-shaped guide member 8 having a size slightly smaller than the inner diameter of.

In particular, in FIG. 5 (b), the end of the guide member 8 on the wire 2 side is formed with a drawing portion 8a formed into a substantially tapered shape by drawing forming. Therefore, when the treatment is performed by projecting the guide member 8 from the guide tube 1 to the outside, the treatment is completed and the functional member B is moved to the guide tube 1
The guide member 8 does not get caught on the guide tube 1 when it is pulled back to, and the operability is not impaired. In addition, the wire 2 side end and the functional member B side end of the guide member 8 are respectively drawn to form the wire 2
It is also possible to connect the and functional member B via the guide member 8 without butt welding.

In FIG. 6, the wire 2 and the functional member B are formed as different members, and these members are connected by a coil spring 9. The outer diameter of the coil spring 9 is smaller than the inner diameter of the guide tube 1, and the inner diameter is larger than the outer diameters of the wire 2 and the functional member B. The coil spring 9 can connect these members by fitting the wire 2 and the functional member B, and the outer diameter after fitting each member is smaller than the inner diameter of the guide tube 1. It is designed to have a small size. Therefore, the coil spring 9 has a function as a connecting member that connects the wire 2 and the functional member B, and a function as a guide member.

As described above, the integrated structure of the wire 2 and the functional member B can be appropriately selected according to the inner diameter of the guide tube 1. In particular, when the wire 2 and the functional member B are configured as different members, it is possible to select and use a material corresponding to the function and strength required for each member (wire 2, functional member B). In addition, the processing method in the manufacturing process can be simplified according to each member. Therefore, it is advantageous in terms of strength and cost.

When the wire 2 and the functional member B are different members, the wire 2 can be manufactured by drawing a stainless steel wire into a predetermined diameter and cutting it into a predetermined length. Further, as the functional member B, it is possible to use a material to which high strength is imparted by subjecting an austenitic stainless steel wire to special wire drawing. That is, the strength of the functional member B can be set to a strength different from the strength of the wire 2. Therefore, it is possible to set the strength of the functional member B to be higher than that of the wire 2. Further, when manufacturing the functional member B, it becomes possible to process the barbs 4a, the cutting edges 5a, and the protrusions 6a on a material obtained by cutting the material into short pieces. Therefore, it is possible to improve the handleability of the raw material in the manufacturing process of the functional member B and to improve the setup property such as attachment to the processing machine.

[0044]

As described in detail above, the medical device according to the present invention is provided with a functional member for collecting a part of living tissue or a functional member for removing and piercing thrombus and the like at the tip of the wire. Since the guide part is configured in part, when the practitioner moves the wire back and forth in the axial direction or rotates it, the guide part comes into contact with the inner surface of the guide tube and guides the moving direction to move the functional member. Then, a part of the living tissue can be collected, or an obstruction such as a thrombus can be removed or perforated.

Further, since the outer diameter of the functional member is set to the inner diameter of the guide tube or less and the length is set to 10 times or less of the guide portion, the slenderness ratio of the functional member is reduced, whereby the bending force acting on the functional member is reduced. The mechanical strength with respect to can be improved.

When a spherical portion is formed at the tip of the functional member, when the functional member is projected from the guide tube and a predetermined work is performed, even if the tip of the functional member comes into contact with a living tissue, a contact site is formed. It is possible to close the opening of the tube when the functional member is housed in the guide tube without damaging the tube.

In the medical device according to the present invention, the functional member is constituted by a rod-shaped member, and the intended treatment is performed by reciprocating the functional member in the longitudinal direction by operating the wire, or by reciprocating and rotating the functional member. You can Therefore, since many moving parts are not required, the outer diameter can be reduced when performing the same function as that of the conventional medical device. For this reason, it has a feature that it can be applied to a thinner endoscope and the range of treatment can be expanded.

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating the overall configuration of a medical device.

FIG. 2 is a side view illustrating a configuration of a functional member.

FIG. 3 is a side view of a functional member having a spherical portion at its tip.

FIG. 4 is a side view illustrating a relationship between a wire and a functional member.

FIG. 5 is a side view illustrating a relationship between a wire and a functional member.

FIG. 6 is a side view illustrating a relationship between a wire and a functional member.

[Explanation of symbols]

 A medical device B functional member 1 guide tube 1a housing portion 1b opening 1c enlarged portion 2 wire 2a guide portion 3 coil spring 4 sampling member 4a barbs 4b, 5b, 6b hemispherical portion 5 removing member 5a cutting edge 6 perforating member 6a protrusion 7 spherical portion 8 Guide member 9 Coil spring

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sato Masaru 743 Nakaakutsu, Takanezawa Town, Shioya District, Tochigi Prefecture Matsutani Manufacturing Co., Ltd.

Claims (3)

[Claims] 1. A guide tube formed of a material having flexibility and a surface having a low friction coefficient, and a guide tube inserted into the inside of the guide tube and having a diameter slightly smaller than an inner diameter of the guide tube. A wire having a guide portion having a small outer diameter, and a functional member formed at the tip of the wire for collecting a part of biological tissue or removing an occluder, and the outer diameter of the functional member is the wire. A medical device, wherein the formed guide portion has an outer diameter that is equal to or less than 10 times the outer diameter of the guide portion. 2. A guide tube formed of a material having flexibility and a surface having a low coefficient of friction, a wire inserted into the guide tube, and a living tissue connected to the tip of the wire. Of the functional member for collecting a part of or removing the blockage, and a guide member attached to the wire and having an outer diameter slightly smaller than the inner diameter of the guide tube, and the outer diameter of the functional member is A medical device characterized by being less than or equal to the outer diameter of the guide member and less than or equal to 10 times the outer diameter of the guide member. 3. The medical device according to claim 1, wherein a spherical portion is formed at the tip of the functional member.