JP5733794B2 - Medical guidewire - Google Patents

Description

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

  A guide wire used as a guide at the time of insertion of a catheter into a blood vessel, ureter, organ, or the like in a medical site or insertion of an indwelling device into an aneurysm formation portion of a blood vessel is already well known. Usually, the 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 to each other at the foremost portion. Is formed.

  Furthermore, a configuration in which the tip of the core wire has a J shape and such a portion is embedded in the most advanced portion has already been disclosed (see Patent Document 1). Such a configuration has an advantage that the tip of the core wire is difficult to come off from the most advanced portion.

  In addition, a guide wire has been already disclosed in which a step portion is formed on the core shaft in the most advanced portion to provide a fixed portion, thereby preventing the core shaft from coming out of the most advanced portion (see Patent Document 2). ).

US Pat. No. 6,217,567 JP 2003-52829 A

  However, in the configuration of Patent Document 1, when the dimension of the most advanced portion is set so that the J-shaped portion is within the most advanced portion, the length along the major axis direction of the guide wire at the most advanced portion is the same. As a whole, the leading edge is enlarged and the selectivity at a branching portion of a blood vessel or the like is lowered. Moreover, although the configuration of Patent Document 2 solves the problem of increasing the size of the most advanced portion, the mechanical strength of the tip end portion of the core shaft is reduced by forming a stepped portion constituting the fixed portion. There is a problem that it ends up.

  Therefore, in view of the above problems, the present invention does not increase the size of the most advanced part, is excellent in selectivity at a branching part such as a blood vessel, and suppresses a decrease in mechanical strength of the tip part of the core shaft, It is an object of the present invention to provide a guide wire that can prevent the shaft from coming off from the most distal portion.

The present invention includes a co Ashafuto, a coil body wound around at least the tip portion of the core shaft, a most distal portion of the distal end portion of the coil body and the tip portion of the core shaft is formed is fixed, A bending portion that is bent in a direction perpendicular to the long axis direction of the guide wire is formed in the distal end portion of the core shaft in the most distal portion . The portion of the guide wire farthest from the center line in the longitudinal section is a guide wire arranged on the outer peripheral side of the coil body relative to the region corresponding to the coil inner diameter of the coil body .

With such a configuration, if acts large external force to be pulled out of the core shaft from the leading edge portion, thereby even when the bent portion is pulled in the outermost tip proximally of the guide wire, Since the bent portion is formed along a direction perpendicular to the longitudinal direction of the guide wire, the frictional resistance between the bent portion and the most distal end portion is increased, whereby the core shaft is pulled out. Resistance can be improved and the core shaft can be prevented from slipping out of the most advanced portion. Further, in a compensatory manner, the bent portion is locked to the coil element wire of the coil body, and the core shaft can be prevented from being completely pulled out from the most distal portion. Furthermore, the bent portion can be formed by simply bending the tip of a general-purpose linear core shaft, and the mechanical strength of the core shaft is extremely reduced even after the bent portion is formed. Hard to do. In addition, since the external shape of the bent portion is simple, the leading edge portion is not enlarged even when the leading edge portion is dimensioned so that the bent portion is accommodated in the leading edge portion. . In particular, the length along the long axis direction of the guide wire at the most distal portion can be shortened. And the selectivity in branch parts, such as a blood vessel, improves because a cutting edge part is reduced in size in this way.

  In addition, a plurality of the bent portions may be formed at the distal end portion of the core shaft.

  With the above configuration, the pull-out resistance due to the bent portion is further increased, so that the core shaft can be more reliably prevented from coming out of the most advanced portion.

  Moreover, the structure which the base end side surface of the said bending part in the said core shaft and the front end side surface of the coil strand in the said coil body are contacting is proposed.

  In the above configuration, even when an external force is applied to pull out the core shaft from the most advanced portion, the core shaft is locked to the coil body via the bent portion of the core shaft. Therefore, it is possible to reliably prevent the core shaft from slipping out of the most advanced portion.

  Moreover, it is preferable that the most advanced part is composed of metal solder whose main component is gold.

  Since the metal solder containing gold as a main component has high rigidity, it is possible to sufficiently ensure the load of the core shaft coming off from the most advanced portion by forming the most advanced portion with the metal solder. Furthermore, it is also possible to reduce the size of the most advanced portion while maintaining an appropriate removal load.

  The present invention can reduce the size of the most advanced portion, has excellent selectivity at a branching portion of a blood vessel, etc., and suppresses the decrease in mechanical strength of the distal end portion of the core shaft, while the core shaft comes out from the most advanced portion. There is an effect that can be surely prevented.

Explanatory drawing which shows the guide wire of Example 1. The guide wire of Example 2 is shown, (a) is a longitudinal cross-sectional view, (b) is the sectional view on the AA line of (a). Explanatory drawing which shows the guide wire of Example 3. Explanatory drawing which shows the guide wire of Example 4. Explanatory drawing which shows the guide wire of Example 5.

  Examples 1 to 5 of the guide wire according to the present invention will be described with reference to the accompanying drawings.

Example 1
As shown in FIG. 1, a medical guide wire 1 </ b> A has a tapered core shaft 2 with a distal end having a small diameter and a proximal end having a large diameter.

  A coil body 3 is fixed to at least the tip of the core shaft 2. More specifically, the coil body 3 is constituted by a single coil having at least a distal end formed in a sparse winding, and the distal end portion and the distal end portion of the core shaft 2 are fixed to each other to form a substantially hemispherical outermost shape. A tip portion 4 is formed. The base end of the coil body 3 is fixed to the core shaft 2 via a base end side fixing portion 5. In the guide wire 1A, the core shaft 2 and the coil body 3 are arranged around the center line L1 in the longitudinal section, and the core shaft 2 and the coil body 3 are fixed to each other. In addition, the said base end side fixing | fixed part 5 is comprised by the well-known technique (for example, an adhesive agent, brazing, or welding) using a well-known material.

  The most advanced portion 4 can be formed by a known technique in the same manner as the base end side fixing portion 5, but contains metal solder containing gold as a main component, for example, 80 mass% or more of gold, The compound whose balance is tin can be preferably used.

  Further, a bent portion 20 that is bent in a direction perpendicular to the major axis direction of the guide wire 1 </ b> A is formed at the distal end portion of the core shaft 2 in the most distal portion 4. And the front-end | tip 20A which is a part furthest from the centerline L1 in the longitudinal cross-section of the guide wire 1A among this bending part 20 is the outer peripheral direction in the said coil body 3 rather than the area | region corresponding to the coil internal diameter D of the said coil body 3. Arranged on the side.

  The bent portion 20 can be formed by bending a tip portion of a general-purpose linear core shaft 2, but other methods may be employed and various selections can be made from known techniques. is there.

  In the guide wire 1A, even if an external force is applied to pull out the core shaft 2 from the most distal end portion 4, the bent portion 20 is in a direction perpendicular to the major axis direction of the guide wire 1A. Accordingly, the frictional resistance between the bent portion 20 and the most distal portion 4 is increased, thereby improving the pull-out resistance of the core shaft 2 so that the core shaft 2 has the most distal portion. 4 can be prevented from slipping out. In addition, the bent portion 20 can be formed by a bending process that is a known technique, so that the manufacturing cost does not increase, and the mechanical strength of the core shaft 2 can be increased even after the bent portion 20 is formed. Has the advantage that it is extremely difficult to lower. Further, since the external shape of the bent portion 20 is simple, the leading edge 4 does not increase in size, and in particular, the length of the leading edge 4 along the long axis direction of the guide wire 1A. The length can be shortened. By reducing the size of the most advanced portion 4 in this way, the selectivity at the branching portion such as a blood vessel is improved. Further, as described above, the distal end 20A of the bent portion 20 is disposed on the outer peripheral side with respect to the region corresponding to the coil inner diameter D of the coil body 3, so that the bent portion 20 is temporarily in the most distal portion 4. Even when the guide wire 1A is pulled in the proximal direction, the bent portion 20 is compensably locked to the coil element wire 31 of the coil body 3, and the core shaft 2 is moved from the most distal portion 4. It can be prevented from completely coming out.

(Example 2)
Hereinafter, the 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.

  As shown in FIGS. 2 a and 2 b, the guide wire 1 </ b> B has a plurality of bent portions 21 to 23 at the distal end portion of the core shaft 2. Specifically, as shown in FIG. 2b, a first bent portion 21 is formed at the distal end portion of the core shaft 2 in a direction away from the center line L1 of the guide wire 1B. A second bent portion 22 is formed along the direction perpendicular to the major axis direction of the guide wire 1B from the distal end portion, and further from the distal end portion of the second bent portion 22 to the center line L1 of the guide wire 1B. A third bent portion 23 perpendicular to the long axis direction of the guide wire 1B is formed in the approaching direction. That is, all of the bent portions 21 to 23 are included in the same plane in the cross section of the guide wire 1B.

  By adopting the configuration including the plurality of bent portions 21 to 23 as described above, the pull-out resistance by the bent portions 21 to 23 is greatly improved, so that the core shaft 2 is more likely to come out of the most distal portion 4. This can be prevented more reliably. Note that the number of the bent portions 21 to 23 is not limited to this, and may be four or more. Of the bent portions 21 to 23, the farthest portion from the center line L1 in the longitudinal section of the guide wire 1B is closer to the outer circumferential direction side of the coil body 3 than the region corresponding to the coil inner diameter of the coil body 3. It may be arranged.

(Example 3)
Hereinafter, the 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.

  As shown in FIG. 3, the guide wire 1 </ b> C is formed by contacting the proximal end surface 201 of the bent portion 20 in the core shaft 2 and the distal end surface 310 of the coil strand 31 in the coil body 3. The core shaft 2 is locked to the coil body 3.

  In the above configuration, even when an external force is applied to pull out the core shaft 2 from the most advanced portion 4, the core shaft 2 is connected to the coil body 3 via the bent portion 20 of the core shaft 2. Therefore, the core shaft 2 can be reliably prevented from coming out of the most distal end portion 4.

Example 4
Hereinafter, the guide wire 1D according to the fourth embodiment will be described with reference to FIG. 4, but the description common to the first to third embodiments is omitted, and the same reference numerals are given in the drawing.

  As shown in FIG. 4, the guide wire 1 </ b> D is in contact with the proximal surface 201 of the bent portion 20 of the core shaft 2 and the distal surface 310 of the coil wire 31 that forms the distal end of the coil body 3. As a result, the core shaft 2 is locked to the coil body 3.

  With the above configuration, the core shaft 2 is locked to the coil body 3 via the bent portion 20, and the bent portion 20 is disposed on the distal end side of the coil body 3 at the most distal end portion 4. As a result, the core shaft 2 can be more reliably prevented from being completely pulled out from the most distal end portion 4. In addition, since the bent portion 20 is disposed in the most distal end portion 4 in a state where the proximal end surface 201 of the bent portion 20 is in contact with the distal end side surface 310 of the coil body 3, the guide wire 1D in the long axis direction is arranged. The length of the most advanced part 4 can be further shortened, whereby the most advanced part 4 can be reduced in size. As a result, the blood vessel selectivity of the guide wire 1D is improved.

(Example 5)
Hereinafter, the guide wire 1E according to the fifth embodiment will be described with reference to FIG. 5, but the description common to the first to fourth embodiments will be omitted, and the same reference numerals are given in the drawing.

  As shown in FIG. 5, the core shaft 2 has a bent portion 24, and the guide wire 1E in which the tip 20A is disposed in a region corresponding to the coil inner diameter D of the coil body 3 is also included in the present invention. Is.

  The present invention described so far is not limited to Examples 1 to 5 described above, and it is of course possible to make design changes as appropriate without departing from the spirit of the present invention. The bent portion according to the present invention includes a bent shape and a curved shape like a bow.

1A to 1E Guide wire 2 Core shaft 3 Coil body 4 Most advanced part 20 to 24 Bent part 31 Coil strand 201 Bend base surface 310 Bend tip surface L1 Center line of coil wire

Claims (4)

And co-Ashafuto,
A coil body wound around at least the tip of the core shaft;
A distal end portion formed by adhering the distal end portion of the coil body and the distal end portion of the core shaft; and
In the most advanced portion, a bent portion that is bent in a direction perpendicular to the long axis direction of the guide wire is formed at the tip of the core shaft .
Of the bent portion, a portion farthest from the center line in the longitudinal section of the guide wire is disposed on the outer peripheral side of the coil body with respect to a region corresponding to the coil inner diameter of the coil body. Guide wire. The distal end portion of the core shaft, guidewire according to claim 1, wherein the bent portion are formed. The guide wire according to claim 1 or 2 , wherein a proximal end side surface of the bent portion of the core shaft is in contact with a distal end side surface of a coil wire in the coil body. The guide wire according to any one of claims 1 to 3 , wherein the most advanced portion is made of metal solder whose main component is gold.

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