Medical device and producing method thereof

Abstract

To provide a medical device capable of provisionally clipping a combinatorial device inserted into a lumen and a producing method thereof.SOLUTION: A medical device 1 includes a reinforcing member 11 braided in a cylindrical shape using an element wire w, and an inner layer 21 arranged in contact with a radial inside of the reinforcing member 11, and a lumen h1 is formed on the radial inside of the inner layer 21, and the inner layer 21 includes a first site 21a formed of a first material m1, and a second site 21b provided at a site other than the first site 21a, and has a sliding resistance of an inner peripheral surface greater than the sliding resistance at the inner peripheral surface of the first site 21a and formed of a second material m2 different from the first material m1.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to medical devices and methods for their manufacture. [Background technology]

[0002] 2. Description of the Related Art When guiding a medical instrument (combination device) such as a guidewire or a catheter from outside the body into a body cavity such as a blood vessel, for example, a medical device such as a guiding catheter is used.

[0003] For such medical devices, it is necessary to quickly introduce the combination device into the body cavity, so a technology has been proposed in which an inner layer with low friction (sliding resistance) is provided on the inner surface that comes into contact with the combination device so as to reduce the sliding resistance with the combination device inserted into the cavity (see, for example, Patent Document 1).

[0004] According to the above-mentioned technology, for example, the entire inner layer is formed using a material such as polytetrafluoroethylene (PTFE) or tetrafluoroethylene-perfluoroalkylvinyl ether copolymer (PFA), thereby reducing the sliding resistance between the inner surface and the co-used device. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 8-168521 Summary of the Invention [Problem to be solved by the invention]

[0006] However, while reducing the sliding resistance as described above allows the combination device to be quickly guided into the body cavity, it also makes the combination device more susceptible to misalignment within the medical device, making it difficult to rotate the guidewire in the appropriate position or to position the balloon of the balloon catheter in the appropriate location.

[0007] The present invention has been made based on the above circumstances, and its object is to provide a medical device capable of temporarily gripping a combination device inserted into an inner cavity, and a method for manufacturing the same. [Means for solving the problem]

[0008] (1) A medical device comprising a reinforcing member braided into a tubular shape using wires, and an inner layer arranged to contact the radially inner side of the reinforcing member, wherein an inner cavity is formed radially inside the inner layer, and the inner layer includes a first portion formed of a first material, and a second portion provided in a portion other than the first portion, having a sliding resistance of an inner circumferential surface greater than the sliding resistance at the inner circumferential surface of the first portion, and formed of a second material different from the first material.

[0009] (2) The medical device described in (1), wherein the reinforcing member has a predetermined passage communicating along a radial direction, is formed of the second material, is connected to the second portion via the passage, and further comprises an outer layer arranged to cover the radial outside of the reinforcing member.

[0010] (3) The medical device according to (1) or (2), wherein the second portion is provided only at the end in the longitudinal direction.

[0011] (4) A method for manufacturing a medical device described in any one of (1) to (3), comprising: a first step of using a tubular reinforcing member braided with wires and arranging a tubular member made of a first material radially inside the reinforcing member; a second step of defining the first portion while forming a through hole penetrating the tubular member after the first step; and a third step of using a second material different from the first material and forming the second portion while filling the passage with the second material after the second step.

[0012] In this specification, the term "distal side" refers to the direction along the longitudinal axis of the medical device, and the direction in which the medical device is inserted deeper (distal) into the body. The term "base end side" refers to the direction along the longitudinal axis of the medical device, and the direction opposite to the distal side. The terms "distal" and "distal portion" refer to the distal portion of any member or portion, and the terms "base end" and "base end portion" refer to the proximal portion of any member or portion. These portions do not necessarily have to include the edge. However, unless otherwise specified, the term "longitudinal direction" refers to the direction along the central axis (tube axis) of the medical device. The term "radial direction" refers to the radial direction perpendicular to the longitudinal axis of the medical device. Effect of the Invention

[0013] The present invention can provide a medical device capable of provisionally gripping a combination device inserted into an inner cavity, and a method for manufacturing the same. [Brief description of the drawings]

[0014] [Figure 1] 1 is a schematic longitudinal cross-sectional view of an embodiment of a medical device in its entirety. [Diagram 2] FIG. 2 is a schematic enlarged longitudinal sectional view showing a part of FIG. [Figure 3A] FIG. 3 is a schematic cross-sectional view taken along line IIIA-IIIA in FIG. 2. [Figure 3B] FIG. 3 is a schematic cross-sectional view taken along line IIIB-IIIB in FIG. 2. [Figure 4] 13 is a schematic longitudinal cross-sectional view showing an enlarged portion of another embodiment of a medical device. FIG. [Figure 5A] FIG. 5 is a schematic cross-sectional view taken along line VA-VA in FIG. 4. [Figure 5B] 5 is a schematic cross-sectional view taken along line VB-VB in FIG. 4. [Figure 6A] 1 is an illustration of one embodiment of a method for manufacturing a medical device. [Figure 6B] 1 is an illustration of one embodiment of a method for manufacturing a medical device. [Figure 6C]1 is an illustration of one embodiment of a method for manufacturing a medical device. [Figure 6D] 1 is an illustration of one embodiment of a method for manufacturing a medical device. [Figure 6E] 1 is an illustration of one embodiment of a method for manufacturing a medical device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings, but the present invention is not limited to the embodiment shown in the drawings. Furthermore, the dimensions of each part shown in the drawings are shown to facilitate understanding of the implementation contents, and do not necessarily correspond to the actual dimensions.

[0016] <Medical Devices> 1 to 3 are schematic cross-sectional views showing one embodiment of a medical device 1. The medical device 1 is a guiding catheter. As shown in FIGS. 1 to 3, the medical device 1 is generally composed of a reinforcing member 11, an inner layer 21, an outer layer 31, and a gripping member 41.

[0017] The reinforcing member 11 is a member braided into a cylindrical shape using wires. Specifically, the reinforcing member 11 can be formed, for example, by braiding wires w into a mesh shape and forming the whole into a cylindrical shape, or by winding wires w in a spiral shape around the longitudinal axis of the medical device 1 and forming the whole into a cylindrical shape. By providing the medical device 1 with the reinforcing member 11, for example, the inner layer 21 described below can be held, and the strength of the entire medical device 1 can be increased.

[0018] The wire w may be a single wire, a twisted wire, or a combination of a single wire and a twisted wire. However, a single wire means one single wire, and a twisted wire means a bundle of wires formed by twisting a plurality of single wires together in advance.

[0019] The wire w may be made of a metal material, a resin material, a composite material thereof, or the like. Examples of the metal material include stainless steel such as SUS304, superelastic alloys such as Ni-Ti alloys, and radiopaque metals such as platinum and tungsten. Examples of the resin material include nylon and polyethylene.

[0020] The reinforcing member 11 may have a predetermined passage c provided in a portion radially outside a portion where the second portion 21b (described later) is located and communicating along the radial direction. By providing the passage c, for example, when forming the second portion 21b described later, the second material m2 can be easily loaded (placed) from the radially outside via the passage c.

[0021] The inner layer 21 is a member disposed so as to be in contact with the radially inner side of the reinforcing member 11. The inner layer 21 has a first portion 21a and a second portion 21b. A lumen h1 is formed on the radially inner side of the inner layer 21, penetrating from the tip end to the base end thereof.

[0022] The first portion 21a is a portion formed of the first material m1. Specifically, the first portion 21a can be provided, for example, in one or more independent portions of the inner layer 21. The first portion 21a may be formed in an annular shape along the circumferential direction of the inner layer 21, or may be formed in a portion of the circumferential direction.

[0023] The second portion 21b is provided in a portion other than the first portion 21a, has a sliding resistance on the inner circumferential surface greater than the sliding resistance on the inner circumferential surface of the first portion 21a, and is formed of a second material m2 different from the first material m1. Specifically, the second portion 21b can be provided in, for example, one or more independent portions of the inner layer 21. The second portion 21b may be formed in an annular shape along the circumferential direction of the inner layer 21, or may be formed in a portion of the circumferential direction.

[0024] The arrangement of the first portion 21a and the second portion 21b in the inner layer 21 is not particularly limited. For example, the second portion 21b may be provided only at the end in the longitudinal direction, or may be provided in the middle. These arrangements can be appropriately determined depending on the position in the medical device that grips the combination device to be inserted.

[0025] In this embodiment, the second portion 21b is provided only in a part of the circumferential direction at the tip portion s in the longitudinal direction of the inner layer 21 (see Figs. 2 and 3B). On the other hand, the first portion 21a is provided in a portion of the inner layer 21 excluding the second portion 21b (see Figs. 2 and 3A).

[0026] When the second portion 21b is provided at the distal end of the medical device, for example, the combination device can be quickly inserted to the distal end of the medical device, and then the combination device can be gripped at the distal end to accurately position the combination device while fine-tuning it without excessive movement. On the other hand, when the second portion 21b is provided at the proximal end of the medical device, the combination device can be inserted slowly and reliably into the medical device. Also, when the second portion 21b is provided midway through the medical device, a combination device such as a balloon catheter whose frictional resistance on the outer circumferential surface changes in the longitudinal direction can be temporarily placed at a specific location in the lumen.

[0027] The outer layer 31 is a member formed of the second material m2 and arranged to cover the radial outside of the reinforcing member 11. The outer layer 31 is connected to the second portion 21b through the passage c. In other words, the second portion 21b of the inner layer 21 formed of the second material m2 and the outer layer 31 formed of the second material m2 are integrally formed through the portion in the passage c formed of the second material m2. Therefore, in combination with the anchor effect between the wires w constituting the reinforcing member 11, the inner layer 21 and the outer layer 31 can be reliably fixed to the reinforcing member 11 by mutual bonding through the portion in the passage c. In addition, by forming the outer surface of the outer layer 31 smoothly, frictional resistance with blood vessels and the like can be reduced, and the medical device can be smoothly advanced and retreated.

[0028] Examples of the first material m1 constituting the first portion 21a include polytetrafluoroethylene (PTFE), FEP (fluorinated ethylene propylene), and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA).

[0029] Examples of the second material m2 constituting the second portion 21b include polyethylene, nylon, polyether block amide, PET (polyethylene terephthalate), and PEEK (polyether ether ketone).

[0030] Examples of such combinations include polytetrafluoroethylene (PTFE) as the first material m1 and polyethylene and nylon as the second material m2. This allows the combination device to easily and quickly advance and retract when passing through the first portion 21a, and increases the gripping force of the combination device when passing through the second portion 21b due to the sliding resistance greater than that of the first portion 21a.

[0031] The gripping member 41 is a member that the operator operates while gripping the medical device 1. The gripping member 41 can be arranged so as to be connected to the base end of the reinforcing member 11. The shape of the gripping member 41 is not particularly limited, but for example, the gripping member 41 may be configured to have a lumen h2 that communicates with the lumen h1 and penetrates from the tip to the base end. In such a case, the lumen h1 and the lumen h2 form a lumen L. During the procedure, a combined device such as a guidewire or a catheter is inserted into the lumen L.

[0032] The method for producing the medical device 1 will be described in detail in the section <Method for producing the medical device>.

[0033] As described above, since the medical device 1 has the above-mentioned configuration, the sliding resistance of the inner circumferential surface of the second portion 21b is higher than that of the first portion 21a, and therefore the combination device inserted into the lumen h1 can be provisionally gripped by the second portion 21b. As a result, by locating the second portion 21b at a desired portion of the inner layer 21, for example, the combination device can be quickly inserted and accurately positioned, or the combination device can be provisionally placed at an appropriate position in the lumen h1.

[0034] In the above-mentioned embodiment, the reinforcing member 11 having a predetermined passage c has been described. However, the reinforcing member does not necessarily have to have a predetermined passage. Even when the second material m2 is loaded (placed) from the radially outer side, the second material m2 can be loaded (placed) through the gap between adjacent braided wires w, w of the reinforcing member 12, as in the medical device 2 shown in Figs. 4 and 5B.

[0035] <Medical device manufacturing method> In the method of the present disclosure, the first step, the second step, and the third step are performed in this order. Hereinafter, the method for manufacturing a medical device will be described in detail with reference to Figs. 6A to 6E. Note that the medical device 1 (see Figs. 1, 2, 3A, and 3B) having a passage c and an outer layer 31 will be described as an example. Figs. 6A to 6E each show a schematic cross-sectional view of a portion corresponding to Fig. 3B.

[0036] [1st step] The first step is to use a tubular reinforcing member 11 braided with wires w, and to place a tubular member t (hereinafter simply referred to as "tube t") made of a first material m1 radially inside this reinforcing member 11.

[0037] The reinforcing member 11 may be, for example, a member formed by braiding wires w in a mesh shape and forming the whole into a cylindrical shape, or a member formed by winding wires w in a spiral shape around the longitudinal axis of the medical device and forming the same into a cylindrical shape. In this embodiment, a cylindrical reinforcing member 11 in which wires w are braided in a mesh shape is exemplified.

[0038] In the first step, as shown in Fig. 6A, specifically, a tube t made of a first material m1 is used and inserted into the inner space of the cylindrical reinforcing member 11 described above so that the inner peripheral surface of the reinforcing member 11 and the outer peripheral surface of the tube t are in contact with each other. Note that it is preferable to arrange the reinforcing member 11 and the tube t so that their respective ends are aligned in the longitudinal direction, but this is not essential. It is sufficient that the reinforcing member 11 and the tube t are arranged so that they are in contact with each other at least in the portion where the through hole p described later is formed.

[0039] [Second process] The second step is a step that is performed after the first step, in which a through hole p that penetrates the tube t is formed while defining the first portion 21a.

[0040] The method for forming the through-holes p is not particularly limited. Examples of the method for forming the through-holes p include a method for mechanically drilling the through-holes p using a drill or a cutter having a predetermined shape, and a method for thermally drilling the through-holes p by irradiating them with laser light (a method for evaporating the through-holes p by heating).

[0041] In this embodiment, as shown in FIG. 6B, a laser beam irradiation device is used to irradiate a predetermined portion of the reinforcing member 11 with laser beam from the radial outside, thereby forming a through hole p only in a part of the circumferential direction at the tip portion s in the long axis direction of the inner layer 21. This defines a first portion 21a (a portion of the tube t other than the portion where the through hole p is formed). In this embodiment, the through hole p of the tube t and the passage c of the reinforcing member 11 are simultaneously formed by irradiating the laser beam. The type and intensity of the irradiated laser beam, as well as the irradiation range, can be appropriately determined so as to form the through hole p, etc.

[0042] [3rd step] The third step is a step of forming the second portion 21b by using a second material m2 different from the first material m1 after the second step while filling the through hole p with the second material m2.

[0043] In the third step, as shown in Fig. 6C, specifically, for example, the second material m2 is heated and melted, and the melted second material m2 is filled into the through hole p to define the second portion 21b. At this time, the mandrel (shown by a two-dot chain line in Fig. 6C) corresponding to the diameter of the lumen h1 to be formed (the inner diameter of the tube t) may be inserted in advance into the inner space of the tube t before the filling. This makes it possible to make the inner circumferential surface of the inner layer 21 to be formed flush (a smooth inner circumferential surface without a step at the boundary between the first portion 21a and the second portion 21b in the longitudinal direction), prevent the second material m2 from wrapping around excessively, and form the second portion 21b only in the predetermined portion.

[0044] The third step of this embodiment also includes a step of forming an outer layer 31 by using a second material m2 different from the first material m1 to cover the radial outside (outer peripheral surface) of the reinforcing member 11. This step may be performed after the second material m2 is filled into the through hole p, or may be performed simultaneously with filling the through hole p with the second material m2 as shown in FIG. 6D. When forming the outer layer 31 and filling the through hole p are performed simultaneously, for example, after covering the reinforcing member 11 with a tube formed of the second material m2, a portion of the tube corresponding to the through hole p is heated and melted, so that the second material m2 can be filled into the through hole p through the passage c and the gap between adjacent braided wires w, w.

[0045] In addition, after filling with the second material m2 as described above, the first material m1 and the second material m2 may be integrated while being heated in a heating furnace, and may be adhered to the reinforcing member 11 (see FIG. 6E).

[0046] During or after the above-mentioned steps, the reinforcing member 11, the inner layer 21, etc. (including the outer layer 31 if present) may be cut to a predetermined length, or the gripping member 41 may be attached. The method for performing the cutting and attachment is not particularly limited, and may be performed using, for example, a known technique.

[0047] As described above, the manufacturing method for a medical device disclosed herein has the above-mentioned configuration, and therefore can easily and reliably form an inner layer 21 having a first portion 21a formed from a first material m1 and a second portion 21b formed from a second material m2.

[0048] Furthermore, since the manufacturing method for the medical device of the present disclosure has the above-mentioned configuration, it can be suitably used for manufacturing the medical device of the present disclosure.

[0049] The present disclosure is not limited to the configurations of the above-described embodiments, but is intended to include all modifications within the scope of the claims and meaning equivalent to the scope of the claims. A part of the configurations of the above-described embodiments may be deleted or replaced with another configuration, or another configuration may be added to the configurations of the above-described embodiments.

[0050] For example, in the above-described embodiment of the medical device and the manufacturing method thereof, the second portion 21b is formed only in a part of the circumferential direction of the inner layer 21. However, the second portion may be formed, for example, in an annular portion along the circumferential direction, or in two or more independent arc-shaped portions along the circumferential direction.

[0051] In the above-mentioned embodiments of the medical device and the manufacturing method thereof, a medical device having a through hole formed in only one location has been described as an example. However, the through hole may be formed appropriately (for example, in two or more locations) so as to correspond to the arrangement of the second portion.

[0052] In the above-described embodiment of the medical device, the medical device 1 is described as having the passage c and the outer layer 31. However, the medical device may be a medical device not having the passage c (see Figs. 4, 5A, and 5B) or a medical device not having the outer layer 31 (see Fig. 6C). The medical device may be a microcatheter, a guide sheath, or the like.

[0053] In addition, as the manufacturing method of the medical device 1 described above, an embodiment including the first to third steps has been described. However, the medical device may be manufactured by other methods. As another method, for example, a tube formed in advance by connecting the first portion 21a and the second portion 21b may be used, and the tube may be inserted into the inner space of the cylindrical reinforcing member 11 so that the inner peripheral surface of the reinforcing member 11 contacts the outer peripheral surface of the tube, and then the tube may be fixed to the reinforcing member 11 while being softened in a heating furnace. In this way, the inner layer 21 arranged so as to contact the radially inner side of the reinforcing member 11 can be obtained. [Explanation of symbols]

[0054] 1,2 Medical Devices 11,12 Reinforcing members 21 Inner layer 21a Part 1 21b 2nd part 31 Outer layer w Bare wire h1 lumen c aisle p Through hole

Claims

1. A reinforcing member braided into a tubular shape using strands of wire, The reinforcing member comprises an inner layer arranged to be in contact with the radially inner side of the reinforcing member, A lumen is formed on the radially inner side of the inner layer. The aforementioned inner layer is A first part formed from the first material, A medical device comprising: a second portion provided in a portion other than the first portion, having an inner circumferential sliding resistance greater than that of the inner circumferential surface of the first portion, and being formed of a second material different from the first material.

2. The reinforcing member has a predetermined passage that communicates along the radial direction, The medical device according to claim 1, further comprising an outer layer formed of the second material, connected to the second portion via the passage, and disposed to cover the radially outer side of the reinforcing member.

3. The medical device according to claim 1 or claim 2, wherein the second portion is provided only at the end in the longitudinal direction.

4. A method for manufacturing a medical device according to claim 1 or claim 2, A first step involves using a tubular reinforcing member braided with strands of wire, and arranging a tubular member made of a first material radially inside this reinforcing member. After the first step, a second step is performed to define the first portion while forming a through hole that penetrates the tubular member, A method for manufacturing a medical device, characterized by comprising: a third step, after the second step, using a second material different from the first material, and forming the second portion while filling the through hole with the second material.

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