Patent Application
20230381462
The technique disclosed in the present specification relates to a guide wire.
In general, guide wires or the like that are inserted into a body, such as into a blood vessel, require good insertability into the blood vessel or the like, and good operability in the blood vessel or the like. In general, a guide wire includes a core shaft, a coil body that covers an outer periphery of the core shaft, and a distal end side joint part that joins a distal end portion of the coil body with a distal end portion of the core shaft.
As for such a guide wire, a guide wire in which the distal end portion of the coil body is fixed to the core shaft by an Au—Sn solder is known (e.g., see JP 2010-214054 A).
As mentioned above, guide wires that are inserted into a blood vessel or the like require a strong joining between the coil body and the core shaft, and meanwhile require good insertability and operability. For example, when a guide wire is advanced from a main vessel with a large vessel diameter (e.g., a parent vessel) to a bifurcated vessel with a small vessel diameter (e.g., a daughter vessel), the distal end of the guide wire may abut against a vessel inner wall at an entrance of the bifurcated vessel. In such a case, there is a tendency that, if the distal end portion of the guide wire has low flexibility (stiff), resistance on the distal end portion of the guide wire increases when the guide wire is further pushed forward, making it more difficult to advance the guide wire toward the distal end side of the bifurcated vessel.
These problems are not limited to the case that the guide wire is advanced from the main vessel to the bifurcated vessel, but are also common to cases that the guide wire is advanced in a vessel having a complex shape.
The present specification discloses a technique capable of solving the problems described above.
The technology disclosed in the present specification can be implemented, for example, as the following aspects.
(1) The guide wire disclosed herein includes a core shaft, a coil body that covers an outer periphery of the core shaft, and a distal end side joint part that joins a distal end portion of the coil body with a distal end portion of the core shaft. The distal end side joint part is made of a resin material. The guide wire further includes a fixation part made of a metal material that joins the coil body with the core shaft on a proximal end side of the distal end side joint part. In the guide wire according to the disclosed embodiments, since the distal end side joint part is made of the resin material, the slidability and flexibility on the distal end portion of the guide wire can be improved. In the guide wire according to the disclosed embodiments, since the fixation part is made of the metal material, the coil body and the core shaft can be firmly joined. Thus, the guide wire according to the disclosed embodiments makes it possible to obtain good flexibility on the distal end portion, while ensuring a joining strength between the coil body and the core shaft.
(2) The guide wire may be configured such that the distal end side joint part is made of an elastomer material. According to the guide wire having this configuration, flexibility on the distal end portion of the guide wire can be enhanced, and therefore, when the guide wire is inserted into a blood vessel or the like, a blood vessel inner wall or the like can be more reliably prevented from being damaged.
(3) The guide wire may be configured such that a gap between the distal end side joint part and the fixation part in the axial direction of the guide wire is smaller than a length of the distal end side joint part in the axial direction. Thus, in the guide wire having this configuration, the gap between the distal end side joint part and the fixation part is relatively small. In other words, in this configuration, the fixation part is located in the vicinity of the distal end of the guide wire. Thus, in the guide wire according to the disclosed embodiments, the joining strength between the coil body and the core shaft can be more effectively ensured on the distal end of the guide wire.
(4) The guide wire may be configured such that the distal end side joint part and the fixation part are continuously arranged in an axial direction of the guide wire. In other words, in the guide wire having this configuration, the fixation part is located in the vicinity of the distal end of the guide wire. Thus, in the guide wire according to the disclosed embodiments, the joining strength between the coil body and the core shaft can be more effectively ensured on the distal end of the guide wire.
(5) The guide wire may be configured such that a length of the distal end side joint part in an axial direction of the guide wire is twice or larger and 10 times or smaller an outer diameter of the coil body. Thus, according to the guide wire having this configuration, the joining strength between the distal end side joint part and the coil body can be more effectively ensured.
(6) The guide wire may be configured so as to include a resin film that covers an outer surface of the distal end side joint part and an outer peripheral surface of the coil body and is made of one or a plurality of resin materials, in which the resin material for the distal end side joint part is the same as at least one of the resin materials for the resin film. Thus, according to the guide wire having this configuration, the adhesiveness between the distal end side joint part and the resin film can be improved, and therefore the resin film can be prevented from peeling off from the distal end side joint part.
The technology disclosed herein can be achieved in various aspects, e.g., in an aspect of a guide wire or a production method thereof.
The terms “a” and “an” are defined as one or more unless this disclosure explicitly requires otherwise. The terms “substantially” and “about” are defined as largely but not necessarily wholly what is specified (and includes what is specified; e.g., “substantially” parallel includes parallel and “about” a value includes the value), as understood by a person of ordinary skill in the art. In any disclosed embodiment, the terms “substantially” and “about” can be substituted with “within [a percentage] of” (meaning within a specified percentage greater than or less than) what is specified, where the percentage includes 0.1, 1, 5, and up to 10 percent.
The terms “comprise” and any form thereof such as “comprises” and “comprising,” “have” and any form thereof such as “has” and “having,” and “include” and any form thereof such as “includes” and “including” are open-ended linking verbs. As a result, a medical device, like a guide wire, that “comprises,” “has,” or “includes” one or more elements possesses those one or more elements, but is not limited to possessing only those elements. Likewise, a method that “comprises,” “has,” or “includes” one or more steps possesses those one or more steps, but is not limited to possessing only those one or more steps.
Any embodiment of any of the devices and methods can consist of or consist essentially of—rather than comprise/include/have—any of the described steps, elements, and/or features. Thus, in any of the claims, the term “consisting of” or “consisting essentially of” can be substituted for any of the open-ended linking verbs recited above, in order to change the scope of a given claim from what it would otherwise be using the open-ended linking verb.
The guide wire 100 is a medical device to be inserted into a blood vessel or the like, in order to guide a catheter (not illustrated) into, e.g., a lesion (constricted part or occluded part) in a blood vessel or the like.
As illustrated in
The core shaft 10 is an elongated member having a small diameter on the distal end side and a large diameter on the proximal end side. In the first embodiment, the core shaft 10 has a small diameter portion 11, a large diameter portion 12, and a tapered portion 13. In
As the material for the core shaft 10, known materials are used, for example, metallic materials, more specifically, stainless steel (SUS302, SUS304, SUS316, etc.), superelastic alloys such as Ni—Ti alloys, piano wires, nickel-chromium based alloys, cobalt alloys, tungsten, or the like are used. The entire core shaft 10 may be made of one material, or each portion of the core shaft 10 may be made of different materials.
As illustrated in
As the material for forming the coil body 20, known materials are used, for example, metallic materials, more specifically, stainless steel (SUS302, SUS304, SUS316, etc.), superelastic alloys such as Ni—Ti alloys, piano wires, nickel-chromium based alloys, cobalt alloys, tungsten, or the like are used.
The distal end side joint part 30 joins the distal end portion of the core shaft 10 with the distal end portion of the coil body 20. The distal end of the core shaft 10 and the distal end of the coil body 20 are fixed so as to be embedded in the distal end side joint part 30. The distal end side joint part 30 has, on the distal end side, a smooth outer peripheral surface (e.g., a substantially hemispherical face, or a columnar face). Preferably, the distal end side joint part 30 is elastic and flexible and is made of one or more resin materials. For such resin materials, e.g., elastomer materials are used, such as thermosetting elastomer resins and thermoplastic elastomer resins. As thermosetting elastomer resins, for example, silicone rubbers, fluororubbers, or the like are used. As thermoplastic elastomers, for example, polyurethane resins, polyester resins, polyamide resins, or the like are used. More preferably, the distal end side joint part 30 contains at least one of the resin materials for the resin part 60 described later. For such resins, e.g., hydrophilic resins or the like, more preferably polyurethane resins or the like, are used. The distal end side joint part 30 may be made of one or a plurality of resin materials. When the distal end side joint part 30 having flexibility on the distal end side is disposed on the core shaft 10, a blood vessel wall can be prevented from being damaged. Also, the resin part 60 makes it possible to improve the slidability of the distal end portion of the guide wire 100. The detailed configuration of the distal end side joint part 30 will be described later.
The proximal end side joint part 40 is a member that joins the proximal end side of the core shaft 10 with the proximal end side of the coil body 20. As the materials constituting the proximal end side joint part 40, known materials are used, such as brazing materials (aluminum alloy braze, silver braze, gold braze, etc.), metal solders (Ag—Sn alloys, Au—Sn alloys, etc.), and adhesives (epoxy-based adhesives, etc.). In the first embodiment, brazing materials are used as the materials constituting the proximal end side joint part 40.
The metal fixation part 50 is a member that joins the coil body 20 with the core shaft 10 on the proximal end side of the distal end side joint part 30. In the first embodiment, the core shaft 10 and the coil body 20 are joined to each other such that a part of each of the core shaft 10 and the coil body 20 is embedded in the metal fixation part 50. More specifically, in the first embodiment, the metal fixation part 50 is formed so as to cover the outer surface of a part of the coil body 20 described above (i.e., a part where the metal fixation part 50 is disposed) such that a thickness of the metal fixation part 50 is substantially uniform, as illustrated in the partial enlarged view of
The resin part 60 is a coat member that is made of one or a plurality of resin materials and covers the outer peripheral surface of the coil body 20 and the outer surfaces of the distal end side joint part 30 and the proximal end side joint part 40. As the resin materials constituting the resin part 60, known materials are used, such as silicone resins. As the resin materials constituting the resin part 60, hydrophilic resins are preferably used, and hyaluronic acid-based resins, polyvinyl alcohol (PVA) resins, or the like are more preferably used. For example, the resin part 60 has a thickness of about 0.002 to 0.1 mm. The resin part 60 is an example of a resin film.
The distal end side joint part 30 has a fixing portion 31 and a most distal end portion 33. The fixing portion 31 is located on the most proximal end side of the distal end side joint part 30 to fix the distal end portion of the coil body 20 with the distal end portion of the core shaft 10. The most distal end portion 33 is disposed on the distal end of the fixing portion 31 in the distal end side joint part 30 and has an almost spherical segment shape with an outer diameter gradually decreasing toward the distal end side. The outer diameter on the distal end of the fixing portion 31 is equal to the outer diameter on the proximal end of the most distal end portion 33. That means, the outer surface of the fixing portion 31 is continuous with the outer surface of the most distal end portion 33. In the first embodiment, the fixing portion 31 and the most distal end portion 33 have an almost circular transverse sectional shape (XY section).
For example, the distal end side joint part 30 has a length L30 of about 0.5 mm to 5 mm in the Z-axis direction (axial direction of the core shaft 10). The length L30 of the distal end side joint part 30 may be, e.g., about twice or larger and 10 times or smaller, more specifically about three times an outer diameter D20 of the coil body 20. For example, the most distal end portion 33 has a length L33 of about 0.45 mm to 1 mm. In the first embodiment, the length L30 of the distal end side joint part 30 is about 4 mm. Preferably, at least four laps of the coil body 20 are embedded in the distal end side joint part 30 in the longitudinal section.
In the Z-axis direction, a length L50 of the metal fixation part 50 is, e.g., about 0.5 mm to 1.5 mm, more specifically about 0.5 mm to 1 mm, from the viewpoint of ensuring the joining strength between the coil body 20 and the core shaft 10. For example, the metal fixation part 50 is located at most 5 mm apart from the most distal end of the guide wire 100, from the viewpoint of ensuring the joining strength between the coil body 20 and the core shaft 10 on the distal end of the guide wire 100.
In the guide wire 100 according to the first embodiment, an end face S30 on the proximal end side of the distal end side joint part 30 (specifically, fixing portion 31) and an end face S50 on the distal end side of the metal fixation part 50 are in contact with each other over their entire faces or over substantially their entire faces. In other words, in the Z-axis direction, the distal end side joint part 30 and the metal fixation part 50 are continuously arranged. In
For example, the guide wire 100 according to the first embodiment can be produced by a method described below. First, the core shaft 10, shaped by machine polishing or the like, and the coil body 20, composed of a wound coil wire, are prepared. The core shaft 10 is inserted into a hollow portion of the coil body 20, and then the distal end side joint part 30, the proximal end side joint part 40, and the metal fixation part 50, which join the coil body 20 and core shaft 10, are formed. To form the distal end side joint part 30, for example, a molten resin is injected into a mold capable of shaping the distal end side joint part 30, and the distal end portions of the core shaft 10 and coil body 20 are dipped into the resin, followed by cooling. Then, to form the metal fixation part 50, a molten brazing material is injected from a gap of the coil body 20 into a position at which the metal fixation part 50 is formed, followed by cooling. The proximal end side joint part 40 is formed by brazing the proximal end side of the coil body 20 with the core shaft 10. Subsequently, these members are dipped into a molten resin to form the resin part 60. The guide wire 100 having the aforementioned configuration can be produced, e.g., by the method as described above.
As described above, the guide wire 100 according to the first embodiment includes the core shaft 10, the coil body 20, and the distal end side joint part 30. The distal end side joint part 30 is made of a resin material. The guide wire 100 further includes a metal fixation part 50. The metal fixation part 50 joins the coil body 20 with the core shaft 10 on the proximal end side of the distal end side joint part 30 and is made of a metal material. In the guide wire 100 according to the first embodiment, since the distal end side joint part 30 is made of a resin material, the slidability and flexibility on the distal end portion of the guide wire 100 can be improved. In the guide wire 100 according to the first embodiment, since the metal fixation part 50 is made of a metal material, the coil body 20 and the core shaft 10 can be firmly joined. Thus, the guide wire 100 according to the first embodiment makes it possible to obtain good flexibility on the distal end portion, while ensuring the joining strength between the coil body 20 and the core shaft 10.
In the guide wire 100 according to the first embodiment, the distal end side joint part 30 is made of an elastomer material. In the guide wire 100 according to the first embodiment, flexibility of the distal end portion of the guide wire 100 can be enhanced, and therefore, when the guide wire is inserted into a blood vessel or the like, a blood vessel inner wall or the like can be more reliably prevented from being damaged.
In the guide wire 100 according to the first embodiment, the distal end side joint part 30 and the metal fixation part 50 are continuously arranged in the axial direction of the guide wire 100. In other words, in the guide wire according to the first embodiment, the metal fixation part 50 is located in the vicinity of the distal end of the guide wire 100. Thus, in the guide wire 100 according to the first embodiment, the joining strength between the coil body 20 and the core shaft 10 can be more effectively ensured on the distal end of the guide wire 100.
In the guide wire 100 according to the first embodiment, a length of the distal end side joint part 30 in the axial direction of the guide wire 100 is twice or larger and 10 times or smaller than an outer diameter D20 of the coil body 20. Thus, in the guide wire 100 according to the first embodiment, the joining strength between the distal end side joint part 30 and the coil body 20 can be more effectively ensured.
The guide wire 100 according to the first embodiment further includes the resin part 60, and the resin material for the distal end side joint part 30 is the same as at least one of the resin materials for the resin part 60. Thus, in the guide wire 100 according to the first embodiment, the adhesiveness between the distal end side joint part 30 and the resin part 60 can be improved, and therefore the resin part 60 can be prevented from peeling off from the distal end side joint part 30.
The guide wire 100A according to the second embodiment includes a metal fixation part 50A instead of the metal fixation part 50 in the guide wire 100 according to the first embodiment. Similarly to the metal fixation part 50, the metal fixation part 50A is a member that joins the coil body 20 with the core shaft 10 on the proximal end side of the distal end side joint part 30 and is made of the metal materials described above. In the second embodiment, the metal fixation part 50A is located away from the distal end side joint part 30. That means, the end face S30 of the distal end side joint part 30 and the end face S50 of the metal fixation part 50A are not in contact with each other over their entire faces. More specifically, a gap Ld between the distal end side joint part 30 and the metal fixation part 50A is smaller than the length L30 of the distal end side joint part 30, e.g., about 0.5 mm to 1 mm. The length L50 of the metal fixation part 50A is equivalent to the length L50 of the metal fixation part 50, e.g., about 0.5 mm to 1.5 mm, more specifically, about 0.5 mm to 1 mm. For example, the metal fixation part 50A is located at most 5 mm apart from the most distal end of the guide wire 100, from the viewpoint of ensuring the joining strength between the coil body 20 and the core shaft 10 on the distal end of the guide wire 100.
In the guide wire 100A according to the second embodiment, the gap Ld between the distal end side joint part 30 and the metal fixation part 50A in the axial direction of the guide wire 100A is smaller than the length L30 of the distal end side joint part 30 in the axial direction. Thus, in the guide wire 100A according to the second embodiment, the gap Ld between the distal end side joint part 30 and the metal fixation part 50A is relatively small. In other words, in the guide wire 100A, the metal fixation part 50A is located in the vicinity of the distal end of the guide wire 100A. Thus, in the guide wire 100A according to the second embodiment, the joining strength between the coil body 20 and the core shaft 10 can be more effectively ensured on the distal end of the guide wire 100A.
The guide wire 100B according to the third embodiment does not have the resin part 60 in the guide wire 100 according to the first embodiment. The guide wire 100B according to the third embodiment exhibits effects excluding the effect of the resin part 60 among the effects in the guide wire 100 according to the first embodiment.
The technology disclosed in the present specification is not limited to the above-described embodiments and can be modified in various forms without departing from the scope of the disclosed embodiments. For example, the following modifications are possible.
Although the configuration in which the outer surface of the coil body 20 is embedded in the metal fixation part 50 is adopted in the first embodiment, the disclosed embodiments are not limited to this configuration. That means, it is possible to adopt a configuration in which the outer surface of the coil body 20 is in contact with the resin part 60 on a portion where the metal fixation part 50 is disposed such that a part of the outer surface of the coil body 20 is not embedded in the metal fixation part 50. The same applies to the second embodiment and the third embodiment. In the third embodiment, it is possible to adopt a configuration in which the outer surface of the coil body 20 is exposed.
Although the configuration in which the end face S30 of the distal end side joint part 30 and the end face S50 of the metal fixation part 50 are in contact with each other over their entire faces is adopted in the first embodiment, the disclosed embodiments are not limited to this configuration. That means, it is possible to adopt a configuration in which at least one or more parts of the end face S30 and/or the end face S50 are not in contact with each other.
In the second embodiment, the gap Ld between the distal end side joint part 30 and the metal fixation part 50 may be equal to or larger than the length L30 of the distal end side joint part 30.
In the above embodiments, the length L30 of the distal end side joint part 30 may be less than twice and more than 10 times the outer diameter D20 of the coil body 20.
In the first and second embodiments, the resin part 60 may be configured to cover at least a part of each outer surface of the distal end side joint part 30 and the metal fixation part 50. In the guide wires 100 and 100A having the resin part 60, the distal end side joint part 30 may be made of a resin material different from the resin material for the resin part 60.
The material for each member according to the above embodiments is merely an example and may be variously modified. Also, the production method for the guide wires according to the above embodiments is merely an example and may be variously modified. For example, although the metal fixation part 50 is formed after the distal end side joint part 30 is formed in the above embodiments, the distal end side joint part 30 may be formed after the metal fixation part 50 is formed. In the above embodiments, although the most distal end portion 33 of the distal end side joint part 30 is configured to have an almost spherical segment shape, the disclosed embodiments are not limited to this configuration, and the most distal end portion 33 may have another shape.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-033173 | Mar 2021 | JP | national |
This application is a continuation application of International Application No. PCT/JP2022/003746, filed Feb. 1, 2022, which claims priority to Japanese Patent Application No. 2021-033173, filed Mar. 3, 2021. The contents of these applications are incorporated herein by reference in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2022/003746 | Feb 2022 | US |
| Child | 18448465 | US |
