JP5392784B2 - Medical guidewire - Google Patents

Description

  The present invention relates to a medical guide wire suitably used in the medical field.

A medical guide wire (medical guide wire) used as a guide when inserting a catheter into a blood vessel, ureter, or organ in a medical field, or inserting an indwelling device into an aneurysm formation part of a blood vessel, Already well known. Usually, the medical guide wire includes a core shaft and a coil body wound around the outer periphery of the distal end portion of the core shaft, and the distal end portion of the coil body and the distal end portion of the core shaft are joined together. .

Furthermore, in the medical guide wire, a core configured by connecting a portion having a high strength in the proximal end portion and a portion made of a superelastic alloy in the distal end portion, and a molded ribbon disposed at the distal end portion of the core; A configuration including the above has already been disclosed (see Patent Document 1). Moreover, the structure which equips a medical guide wire with a core, an outer side coil body, and the inner side coil body formed with the radiopaque material is already disclosed (refer patent document 2).

International Publication No. 95/19800 US Pat. No. 5,345,945

However, in the medical guide wire described in Patent Document 1, a molded ribbon is provided at the distal end portion, and both the ease of shaping and the shape restoration property are compatible, but the cores join different parts to each other. Therefore, the stress is concentrated on the joint portion and the torque transmission performance of the medical guide wire is lowered. As a result, there is a problem in selectivity in the blood vessel. In addition, the medical guide wire described in Patent Document 2 has a double coil structure, and thus the medical guide wire is excellent in torque transmission but is not easily shaped. There was a problem in the selectivity in the interior.

Therefore, the present invention provides a core shaft, a coil body fixed to the core shaft so as to cover at least the tip portion of the core shaft, and disposed inside the coil body, and parallel to the core shaft tip portion. an elongated member in a state secured to the distal end of the core shaft, a medical guide wire and a leading edge portion of the tip and the tip of the coil body is fixed in the core shaft, the length The scale member is made of a superelastic alloy, the distal end of the long member is spaced from the most distal portion in the proximal direction, and the coil body extends from the distal end of the elongated member to the most distal portion. The medical guide wire is characterized in that the pitch of is set wider than that of other portions .

In the above configuration, since the long member is made of a superelastic alloy such as NiTi, and the distal end of the long member is separated from the distal end portion in the proximal direction, the shape of the distal end portion of the medical guide wire is restored. The ease of shaping in the vicinity of the most advanced portion can be ensured while enhancing the performance.

Moreover, the said structure WHEREIN: An inner side coil body may be arrange | positioned so that at least the front-end | tip of the said elongate member may be covered inside the said coil body, and the said inner side coil body may be fixed to the front-end | tip part of the said core shaft.

When the inner coil body is arranged as in the above configuration, the shape restoring property and operability of the distal end portion of the medical guide wire are improved by the inner coil body, so that the selectivity in the blood vessel or the like is improved. Furthermore, by disposing the inner coil body so as to cover at least the distal end of the long member, the distal end of the long member protrudes from the inner coil body when the distal end portion of the medical guide wire is bent. Therefore, the safety of the medical guide wire can be ensured.

The inner coil body may be disposed so as to cover a distal end and a proximal end of the elongated member, and the distal end of the inner coil body may be separated from the most distal portion in the proximal direction.

In the above configuration, since the inner coil body completely encloses the entire long member, when the distal end portion of the medical guide wire is bent, the distal end and the proximal end of the elongated member are Protruding from the inner coil body can be prevented, and the safety of the medical guide wire can be ensured. Moreover, since the front-end | tip of an inner side coil body is spaced apart from the said most advanced part in the base end direction, the shaping ease of the said most advanced part vicinity is securable.

Furthermore, the said inner side coil body may be comprised with the multi-strand coil.

By adopting a multi-strand coil having a strong restoring force in this way, the shape restoring property of the distal end portion of the medical guide wire is further improved.

The medical guide wire of the present invention is excellent in the shape restoring property at the distal end portion thereof and the ease of shaping in the vicinity of the most distal end portion, and also excellent in selectivity in a blood vessel or the like.

Explanatory drawing which shows the front-end | tip part of the medical guide wire concerning Example 1. FIG. Explanatory drawing which shows the front-end | tip part of the medical guide wire concerning Example 2. FIG. Explanatory drawing which shows the front-end | tip part of the medical guide wire concerning Example 3. FIG. Explanatory drawing which shows the front-end | tip part of the medical guide wire concerning Example 4. FIG.

Examples 1 to 4 of the medical guide wire according to the present invention will be described with reference to FIG.

Example 1
As shown in FIG. 1, the medical guide wire 1 </ b> A includes a tapered round bar-shaped core shaft 2 </ b> A having a small diameter on the distal end side and a large diameter on the proximal end side.

Although the material which forms the said core shaft 2A is not specifically limited, For example, stainless steel alloys, such as SUS304 and SUS316, a cobalt type alloy, a piano wire, or a superelastic alloy etc. can be used. Among these, particularly preferred are high-strength alloys such as stainless steel alloys, cobalt alloys, and piano wires. When such a high-strength alloy is used, the operability of the medical guide wire 1A is improved, and further, selectivity in a blood vessel or the like is improved.

Further, an outer coil body 3 as a coil body in the present invention is fixed to the tip portion of the core shaft 2A. More specifically, as shown in FIG. 1, the outer coil body 3 is composed of a single-wire coil or the like, wound around the outer periphery of the distal end portion of the core shaft 2A, and the distal end of the outer core body 2A. Adhering to the tip, the most hemispherical most distal portion 4 is formed. Further, the base end of the outer coil body 3 is fixed to the core shaft 2A via a fixing portion (not shown). In addition, the forefront portion 4 has a shape that is larger than the outer diameter of the tip of the core shaft 2.

A known material can be used as the material for forming the outer coil body 3, for example, a stainless steel alloy such as SUS304 or SUS316, a radiolucent metal such as a cobalt alloy, a piano wire, or a superelastic alloy, or , Platinum, gold, tungsten, or radiopaque metals such as alloys based on these elements can be used.

A long member 5 made of a superelastic alloy such as NiTi is fixed to the tip of the core shaft 2A via an adhesive layer 5A. The elongate member 5 is disposed inside the outer coil body 3 and is disposed in parallel with the axial direction of the distal end portion of the core shaft 2A. Further, the distal end is proximal to the distal end portion 4 Separated in the direction. For the adhesive layer 5A, a known technique using a known material (for example, adhesive, brazing, or welding) can be suitably employed, and the long member 5 is extended along the axial direction of the long member 5. May be formed over the entire length, or may be partially formed with respect to the long member 5.

Further, in the outer coil body 3, the pitch is densely configured at least in a section corresponding to the portion from the distal end to the proximal end of the long member 5, and the distal end portion of the medical guide wire 1A is It prevents the distal end or the base end of the long member 5 from protruding from the outer coil body 3 when bent. On the other hand, in the outer coil body 3, in the section corresponding to the portion from the distal end of the long member 5 to the most distal end portion 4, the pitch is set wider than other portions, The ease of shaping of the distal end portion of the guide wire 1A is ensured.

The medical guide wire 1A having the above configuration is excellent in the shape restoring property of the distal end portion of the medical guide wire 1A because the long member 5 is made of a superelastic alloy. Since it is spaced apart from the distal end portion 4 in the proximal direction, the shapeability in the vicinity of the most distal end portion 4 is excellent.

(Example 2)
Hereinafter, the medical guide wire 1B according to the second embodiment will be described with reference to FIG. 2, but the description common to the first embodiment is omitted, and the same reference numerals are given in the drawing.
An inner coil body 6 is disposed inside the outer coil body 3 at the distal end portion of the core shaft 2A so as to cover the distal end and the base end of the long member 5. More specifically, the inner coil body 6 is formed of a multi-strand coil and is wound around the outer periphery of the distal end portion of the core shaft 2A, and the distal end is separated from the most distal end portion 4 in the proximal direction. ing. The inner coil body 6 is fixed to the core shaft 2A via a fixing portion 7A provided at the distal end and a fixing portion 7B provided at the proximal end. For the fixing portions 7A and 7B, a known technique (for example, adhesive, brazing, or welding) using a known material can be suitably employed.

Further, in the outer coil body 3, the pitch is set wider than the other parts in the section corresponding to the tip of the inner coil body 6 and the most distal end portion 4. The shapeability of the distal end portion of the guide wire 1B is ensured.

The medical guide wire 1B is provided with the inner coil body 6 so as to cover the elongated member 5 inside the outer coil body 3, and thus has an excellent shape restoring property at the distal end portion of the medical guide wire 1B. Since the distal end of the inner coil body 6 is separated from the most distal end portion 4 in the proximal direction, the shapeability in the vicinity of the most distal end portion 4 is also ensured.

Further, since the inner coil body 6 completely encloses the entire elongate member 5, when the distal end portion of the medical guide wire 1B is bent, the distal end and the proximal end of the elongate member 5 are It does not protrude from the inner coil body 6, and the safety of the medical guide wire 1B is ensured.

Furthermore, since the inner coil body 6 is a multi-strand coil having a strong restoring force, the shape restoring property of the distal end portion of the medical guide wire 1B is further improved.

In the above configuration, the inner coil body 6 employs a multi-strip coil, but the present invention does not exclude the configuration in which the inner coil body 6 is a single wire coil. Further, the inner coil body 6 may be arranged in a state of covering at least the tip of the long member 5.

Further, the material of the inner coil body 6 described so far is not particularly limited. For example, a stainless steel alloy such as SUS304 or SUS316, a cobalt-based alloy, a piano wire, or a radiolucent metal such as a superelastic alloy, or Radiopaque metals such as platinum, gold, tungsten, or alloys based on these elements can be used.

In addition, when it is desired to impart shape restoring property to the distal end portion of the medical guide wire 1B, it is preferable to form the inner coil body 6 using the above-mentioned superelastic alloy when selecting the above-described materials. Moreover, when it is desired to give selectivity in the blood vessel or the like to the distal end portion of the medical guide wire 1B, it is preferable to form the inner coil body 6 using the above-described stainless alloy or the above-described cobalt-based alloy. Moreover, when it is desired to impart radiopacity to the distal end portion of the medical guide wire 1B, it is preferable to form the inner coil body 6 using the radiopaque alloy described above.

(Example 3)
Hereinafter, the medical guide wire 1C according to the third embodiment will be described with reference to FIG. 3, but the description common to the first and second embodiments is omitted, and the same reference numerals are given in the drawing.
A medical guide wire 1C shown in FIG. 3 is a tip portion of a core shaft 2B, and a portion 8 between the long member 5 and the most distal end portion 4 is flattened by press working or the like. is there. With such a configuration, the ease of shaping of the distal end portion of the medical guide wire 1C is improved.

Example 4
Hereinafter, although the medical guide wire 1D according to the fourth embodiment will be described with reference to FIG. 4, the description common to the first to third embodiments is omitted, and the same reference numerals are given in the drawing.
A medical guide wire 1D shown in FIG. 4 is a tip portion of a core shaft 2B, and a portion 8 between the long member 5 and the most distal end portion 4 is flattened by pressing. . With this configuration, the ease of shaping of the distal end portion of the medical guide wire 1D is improved.

The present invention is not limited to the first to fourth embodiments described above, and it is of course possible to make design changes as appropriate without departing from the spirit of the present invention.
For example, in Examples 2 and 4, in order to prevent the long member 5 from being detached from the core shafts 2A and 2B, the core shafts 2A and 2B, the long member 5, and the inner coil body 6 are used. May be fixed integrally.

In Examples 1 to 4, the shape of the long member 5 may be, for example, a round cross-section wire or a ribbon, a tube shape such as a spring or a hypotube, or a stranded wire. And various forms can be selected as appropriate.

Moreover, in Examples 1-4, although the elongate member 5 fixed to the said core shaft 2A, 2B is single, it is not limited to this, The elongate member 5 may be plural. . Further, when a plurality of long members 5 are employed, the long members 5 may all be of the same shape, or may be used in combination with different shapes (for example, round cross-section wires and ribbons) as appropriate. May be.

1A to 1D Medical guide wires 2A, 2B Core shaft 3 Outer coil body (coil body)
4 Cutting edge 5 Long member 6 Inner coil body

Claims (4)

A core shaft;
A coil body fixed to the core shaft so as to cover at least the tip of the core shaft;
Is disposed inside the coil body, an elongated member secured to the distal end of the core shaft in the state of parallel to the core shaft tip,
A medical guide wire comprising: a distal end portion to which a distal end of the core shaft and a distal end of the coil body are fixed ;
The long member is made of a superelastic alloy,
The distal end of the long member is spaced from the most distal portion in the proximal direction ,
The guide wire for medical use , wherein the coil body has a wider pitch from the distal end of the long member to the most distal portion than other portions . The medical guide wire according to claim 1, wherein an inner coil body is disposed inside the coil body so as to cover at least a distal end of the elongated member, and the inner coil body is fixed to a distal end portion of the core shaft. . The inner coil body is disposed so as to cover a distal end and a proximal end of the elongate member, and the distal end of the inner coil body is spaced from the most distal portion in the proximal direction. Medical guide wire. The medical guide wire according to claim 2 or 3, wherein the inner coil body is constituted by a multi-strand coil.

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