JP2002272850A - Catheter tube and method for manufacturing it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new catheter tube having excellent operability and kink resistance, and to provide a method for manufacturing the catheter tube. SOLUTION: In the catheter tube 1 obtained by embedding multiple reinforcing linear bodies 7 integrally into a resin tube main body 2 except its insertion tip part 3 spirally, linearly or in a woven state, the hardness of the bodies 7 is lowered from the hand part of the main body 2 toward the part 3 in multi- stages. Thus, the rigidity of the main body 2 is lowered from the hand part to an insertion tip side in multi-stages, thereby a bending radius can be reduced and the kink resistance is improved without deteriorating operability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical catheter tube and a method for manufacturing the same.

[0002]

2. Description of the Related Art In the medical field in recent years, a treatment method using a catheter tube, which is a tube-shaped medical instrument, has been put to practical use and has exhibited an excellent treatment effect.

[0003] In this treatment method using a catheter tube, for example, a distal end of a catheter tube, which is a resin tube, is inserted into a living body from a certain part of the body surface, and the distal end is inserted into a deep part of the living body using a blood vessel or the like. After pushing down to the affected area and injecting the drug solution etc. directly into the affected area, it does not involve a large incision or suturing like conventional surgery, so the patient's physical -It is possible to exert an excellent effect that the mental load is greatly reduced and the treatment time and the like can be shortened.

[0004] A catheter tube used for such treatment generally has a length of several tens of cm to several meters, and is inserted deep into a living body using a blood vessel or the like as described above. Therefore, flexibility is required to easily deform along complex blood vessels,
An appropriate rigidity is also required to reliably transmit the rotational force and the pushing force at the time of insertion and improve operability. In addition, it is also required to be able to be easily inserted into a thin blood vessel, and to be as thin and as thin as possible in order to inject a drug solution or the like efficiently.

In order to satisfy such various requirements, a conventional catheter tube is, for example, as shown in FIG.
The tube main body part a, which requires rigidity, is formed of a highly rigid resin, and the insertion tip part b, which requires flexibility.
Is formed of a soft resin, and this insertion tip portion b is joined to the tip of the tube body portion a to be integrated, or the entire tube is formed of a soft resin, and the insertion portion b is formed on the tube body a side except the insertion tip portion b. The linear body is helically or linearly embedded or reinforced in a braided state so as to satisfy the characteristics required for the catheter tube.

[0006]

However, in such a conventional catheter tube, a kink is generated when a blood vessel reaches a branch portion or the like during a pushing operation or the like, that is, a bending radius is reduced. At this point, the lumen may be rapidly collapsed, and subsequent insertion may not be possible.

For this reason, it is necessary to impart a certain degree of flexibility to the tube body portion a. However, if the tube body portion is too soft, the pushing transmission force and the rotation transmission force from the hand portion to the insertion distal end side are insufficient, so that operability is poor. Is significantly worsened.

[0008] Therefore, in the treatment with such a catheter tube, there are many cases where it is difficult to select and operate an insertion path, and a lot of experience and a high technique are required in order to properly handle this. There is.

The present invention has been devised in order to effectively solve such problems, and an object of the present invention is to provide a novel catheter tube having excellent operability and kink resistance and a method for manufacturing the same. To provide.

[0010]

According to the present invention, there is provided a resin tube body having a plurality of reinforcing linear members inside a resin tube body except for an insertion end portion thereof. In the catheter tube integrally embedded in the spiral shape, the straight shape, or the braided state, the hardness of the linear body is reduced in multiple stages from the proximal portion of the tube main body toward the insertion distal end portion.

As a result, the rigidity of the tube body is reduced in multiple stages from the hand portion to the insertion tip side,
It is possible to reduce the bending radius as compared with a tube body having a uniform rigidity as in the related art, and it is possible to effectively suppress the occurrence of kink during insertion. Further, since the rigidity of the tube body is not reduced uniformly, the pushing transmission force and the rotation transmission force can be maintained, and the operability is not deteriorated.

More specifically, as set forth in claim 2,
The hardness of the linear body can be changed stepwise in the longitudinal direction by forming the linear bodies by connecting short lines having different hardnesses in the longitudinal direction in order.

According to a third aspect of the present invention, the tube main body is formed by forming a linear body on the inner tube and covering the outer tube on the linear body.
The linear body can be reliably embedded in the tube main body without being exposed on the surface and inside.

Further, such a catheter tube is formed by forming a plurality of linear bodies in which short wires having different hardnesses are sequentially joined in the longitudinal direction, and this linear body is formed into an inner layer tube. It can be easily manufactured by arranging it in a spiral, straight or braided state except for its insertion tip, and then coating the outer tube on the inner tube so as to cover this linear body.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows an embodiment of a catheter tube 1 according to the present invention.

As shown in the figure, the catheter tube 1 is made of a resin tube body 2 having a length of several tens cm to several meters.
Has a structure in which a flexible insertion tip 3 is integrally formed at the tip of the insertion tip 3. The insertion tip 3 is inserted into a living body through the insertion tip 3, and the tube main body 2 is pushed in.
To reach a predetermined affected part. In the figure, reference numeral 8 denotes a connecting portion for connecting a drug solution injector (not shown) or the like to the proximal portion of the catheter tube 1.

Further, this catheter tube 1 is shown in FIG.
And as shown in FIG. 3, an inner layer tube 4 forming an inner wall.
Has a multi-layer structure in which an outer tube 5 is covered around the outer tube 5. A reinforcing member 6 is embedded between the inner tube 4 and the outer tube 5 on the tube body 2 side.

In the embodiment of the present invention, the reinforcing member 6 is formed by spirally winding a plurality of linear members 7 made of stretched nylon or the like around the inner tube 4. As shown in FIG. 4, each linear body 7 constituting the reinforcing body 6 has a plurality of short lines each having a different hardness and having a length of several tens of cm.
That is, in this embodiment, eight short lines 7a, 7
b, 7c, 7d, 7e, 7f, 7g, and 7h are connected in the longitudinal direction in the order of hardness, and the hardness is multistage from the hand side of the tube body 1 to the insertion tip side, that is, in eight stages. It is getting lower gradually throughout.

Therefore, in the catheter tube 1 of the present invention in which the reinforcing member 6 composed of such a linear member 7 is incorporated, the hardness of the tube main body 2 is multistep from the hand portion to the insertion tip side. It is lower.

Therefore, in the catheter tube 1 of the present invention, the bending radius of the tube main body 2 can be made smaller than that of the conventional tube main body having a uniform rigidity. Can be effectively suppressed. Further, since the rigidity of the tube main body 2 is not uniformly reduced, the pushing transmission force and the rotation transmission force can be maintained, so that the operability is not deteriorated.

The resin constituting the inner tube 4 and the outer tube 5 is not particularly limited, and as in the case of the conventional materials, a fluorine-containing resin such as PTFE, PFA, ETFE, vinyl chloride, vinylidene, Polyester resin such as polyethylene, polypropylene, or polyethylene terephthalate, or polyurethane, nylon, Kevlar, polyimide, or the like can be used.

Further, the material constituting the linear body is not particularly limited to nylon, and for example, polyethylene, propylene, Kevlar, polyimide, polyurethane or the like can be used alone or blended.

Further, the linear member 7 whose hardness varies in multiple stages
In addition to the above-described embodiments, single wires having different diameters are sequentially joined in accordance with their thickness, or when a single large-diameter single wire is stretched, the stretching ratio is varied in multiple stages. The diameter may be gradually reduced from the hand to the insertion tip.

[0025]

EXAMPLES Next, specific examples of the present invention will be described together with comparative examples. (Example) As shown in Table 1 below, an inner layer tube (inner diameter 90) made of PTFE (polytetrafluoroethylene) was used.
0 μm, thickness 30 μm), and as shown in Table 2, eight linear bodies (stretched nylon, outer diameter 120 μm round wire) having a different Young's modulus in the longitudinal direction are spirally wound at a pitch of 2 mm as reinforcements. After reinforcement, a nylon elastomer (Shore D hardness: 50) is coated around the periphery and the outer diameter is 2200μ.
m, a tube having a total length of 2300 μm was prepared, and its operability and kink resistance were evaluated according to the following evaluation methods. (1) Evaluation method of operability As shown in FIG. 5, first, a glass tube G having a total length of 1500 mm and an inner diameter of 3.5 mm whose tip is bent to a radius of 300 mm is filled with physiological saline, and then the glass tube is filled. G, insert the above tube C into the glass tube G
Align with the curved tip. Next, the proximal portion of the tube C was twisted over four stages of 90 ° -180 ° -270 ° -360 °, and the twist following angle of the insertion tip was measured. (2) Evaluation method of kink resistance After making a large loop toward the proximal part with 50 mm from the tube tip in a straight line state, squeeze the loop and slowly reduce the diameter, causing kink (crushing of the lumen) The diameter at the time was measured.

[0026]

[Table 1]

[0027]

[Table 2]

(Comparative Example 1) As shown in Table 3 below, a linear body made of a stretched nylon, a round wire having an outer diameter of 120 µm, and having a Young's modulus uniform over the entire length (100 MPa)
a) A tube was prepared under the same conditions as in the example, except that it was placed at a portion except for 250 mm from the tip, and the operability and kink resistance were evaluated in the same manner as in the example. I went in.

[0029]

[Table 3]

(Comparative Example 2) As shown in Table 4 below, a linear body made of a drawn nylon, a round wire having an outer diameter of 120 μm, and having a Young's modulus which is uniform (100 MPa) over the entire length.
a) A tube was prepared under the same conditions as in the example, except that it was placed at a position other than 450 mm from the tip, and the operability and kink resistance were evaluated in the same manner as in the example. I went in.

[0031]

[Table 4]

As a result, as shown in Table 5 below, in the tube according to the embodiment of the present invention, the twist follow-up angles of the insertion tip are 70 °, 150 °, 200 °, and 320 °, respectively. And excellent operability. Further, the diameter at which kink occurred was as small as 40 mm, and excellent kink resistance was exhibited.

On the other hand, in Comparative Example 1, the twist following angle was high and excellent operability was exhibited, but kink occurred at a bending radius of 120 mm, and the kink resistance was poor. On the other hand, in Comparative Example 2, in terms of kink resistance, excellent results comparable to those of the present example were shown because the reinforcing member was not provided at the curved portion, but the twist following angle was low and the operability was remarkably low. It got worse.

[0034]

[Table 5]

[0035]

In summary, according to the present invention, since the rigidity of the tube main body changes in multiple stages along the longitudinal direction, excellent operability and kink resistance can be exhibited. As a result, it is possible to reduce the difficulty in inserting the catheter tube into the living body, and to achieve excellent effects such as greatly contributing to the further spread of the treatment using the catheter tube.

[Brief description of the drawings]

FIG. 1 is a side view showing one embodiment of a catheter tube according to the present invention.

FIG. 2 is a partially broken side view showing a portion A in FIG.

FIG. 3A is an enlarged sectional view taken along line AA in FIG.
FIG. 3B is an enlarged sectional view taken along line BB in FIG. 2.

FIG. 4 is an explanatory view showing a linear body constituting a reinforcing body of the catheter tube of the present invention.

FIG. 5 is a conceptual diagram illustrating an operability evaluation method performed in the present embodiment.

FIG. 6 is a side view showing an example of a conventional catheter tube.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Catheter tube 2 Tube main body 3 Insertion tip part 4 Inner tube 5 Outer tube 6 Reinforcement 7 Linear body 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h Short line

Continued on the front page (72) Inventor Toshiharu Goto 5-1-1, Hidaka-cho, Hitachi City, Ibaraki Prefecture Within Hitachi Cable Research Institute, Ltd. (72) Inventor Hirotoshi Okubo 5-1-1 Hidaka-cho, Hitachi City, Ibaraki Prefecture No. 1 F Term in Hitachi Cable, Ltd. Research Institute of Technology (reference) 4C167 AA01 BB11 BB14 BB15 BB16 BB38 CC08 GG04 GG05 GG06 GG07 GG08 GG09 GG10

Claims (4)

[Claims] 1. A catheter tube in which a plurality of reinforcing linear bodies are integrally embedded in a resin tube main body in a helical, linear or braided state except for an insertion end portion thereof. Characterized in that the hardness of the catheter tube is reduced in multiple stages from the hand of the tube body toward the insertion tip. 2. The catheter tube according to claim 1, wherein each of the linear bodies is formed by connecting short wires having different hardness in the longitudinal direction in order. 3. The catheter tube according to claim 1, wherein the tube body has a linear body on an inner tube, and the outer tube is coated on the linear body. . 4. A plurality of linear bodies formed by sequentially joining short wires having different hardnesses in the longitudinal direction thereof, and the linear bodies are formed into a spiral shape or a linear shape on an inner tube except for an insertion end portion thereof. A method for manufacturing a catheter tube, comprising, after being arranged in a braided state, covering an outer tube on an inner tube so as to cover the linear body.