JPH0751069Y2 - Medical guide wire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial field of use" The present invention relates to a medical guide wire suitable for a catheter guide wire used for inserting a catheter into a blood vessel, ureter, bile duct, trachea, etc. .

"Prior Art" In recent years, medical guidewires have been used as inspection and treatment instruments for tubular organs of the human body such as blood vessels, ureters, bile ducts, and tracheas. For example, in cardiac catheterization, a guide wire is inserted prior to percutaneously inserting a catheter in order to administer a drug such as a contrast agent to a blood vessel.

As the medical guide wire, for example, a wire made of a metal such as stainless steel or a shape memory alloy, the tip of which is formed in a taper shape, or a coil in which a thin wire rod is closely wound is attached to the tip of the wire. Various types have been proposed, such as a coil and a coil in which a core wire is inserted.

In these guide wires, there is some rigidity on the base side so that the operation at hand extends to the distal end, and the distal end is formed sufficiently flexible so as not to damage the tissue during insertion. Especially required.
Therefore, as described above, the tip of the wire is formed in a taper shape, or the coil is attached to the tip of the wire,
A core wire is inserted into the coil to improve the rigidity on the base side and the flexibility on the tip side.

As one of such guide wires, a guide wire as shown in FIG. 2 has already been proposed. In the figure, reference numeral 31 is a wire body, and a tip portion 31a is formed in a tapered shape. Reference numeral 32 is a coil closely wound, the base end portion of which is welded to the tip end portion 31a of the wire body 31, and the tip end portion is melted to form a curved head portion 33. The tip end 31a of the wire main body 31 has the most distal end of the head portion 33a.
Is welded to the wire main body 31, and the coil 32 is integrally attached to the wire body 31.

FIG. 3 shows another conventional example in which a coil is attached to the tip of a metal wire. In the figure, reference numeral 41 is a metal wire body, and a tip portion 41a is formed in a tapered shape. A coil 42 tightly wound around the tip 41a and a safety wire 44 disposed inside the coil 42 are closely wound.
The base end of is welded. The tip of the coil 42 is melted to form a curved head 43, and the safety wire 44 is
The tip end of is welded to the head 43.

"Problems to be solved by the invention" In the guide wire shown in FIG. 2, the tip end 31a of the wire body 31 is welded to the coil 32 so that the tip end portion has flexibility, and the tip end of the wire body 31 is The extension of the coil 32 is regulated by welding the tip of the portion 31a to the head 33 of the coil 32.

However, in the above structure, although the coil 32 has the loop at the base end thereof welded to the peripheral surface of the tip end portion 31a of the wire body 31, the portion 32a where 32 separates from the wire body 31 is:
It is a single wire. That is, the load applied to the coil 32 is the portion where the coil 32 separates from the wire body 31.
Focus on one wire of 32a. In addition, the tip of the wire body 31 welded to the head 33 through the center of the coil 32.
In practice, 31a is very thin, and it is often impossible to obtain sufficient strength for the load applied to the coil 32.
Therefore, with this guide wire, there is a risk that the coil 32 may break at the portion 32a that separates from the wire body 31 during use.

In addition, the guide wire shown in FIG.
The tip portion 41a of 41 is not connected to the head portion 43 of the coil 42 at its tip, but instead the safety wire 44 connects the tip portion 41a of the wire body 41 and the head portion 43 of the coil 42, The expansion of the coil 42 is restricted.

However, also in this guide wire, the portion 42a where the coil 42 separates from the wire body 41 is a single wire, and the load applied to the coil 42 is concentrated in this portion. Further, the safety wire 44 is generally a flat wire, whereas the tip portion 41a of the wire body 41 is tapered, so that the contact area at the welded portion cannot be wide and sufficient fixing force cannot be obtained. . Therefore, even in this guide wire, there is a risk that the connecting portion between the wire body 41 and the coil 42 may be broken during use.

Further, as described above, since the safety wire 44 is generally made of a flat wire, the rigidity of the distal end portion tends to be directional, and the effect of softening the distal end portion by the coil 42 is impaired, and the operability is reduced. It was a cause of worsening.

Therefore, an object of the present invention is to provide a medical guide wire in which the strength and flexibility of the distal end portion are both satisfied.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the medical guide wire of the present invention has a metal wire whose tip is tapered, and one end of which is welded to the tip of this wire, and the other end is A metal coil that is melted to form a curved head portion, and a metal mesh that is disposed inside the metal coil, one end of which is welded to the tip of the wire, and the other end of which is welded to the head portion of the metal coil. It is characterized by consisting of.

[Operation] In the medical guide wire of the present invention, a metal mesh is used instead of the safety wire in the conventional guide wire. Since the metal mesh has a certain degree of flexibility and can be bent relatively freely, a wide contact area can be taken when welding to the tip of the wire body, and a sufficient fixing force is obtained. be able to. Furthermore,
Metal mesh is more resistant to bending and other loads than safety wire. Therefore, by welding one end of the metal mesh to the tip of the wire body and welding the other end to the head of the coil, it is possible to prevent elongation of the coil and breakage of the welded portion between the coil and the wire body. In addition, since the metal mesh has flexibility in all directions, the flexibility of the distal end portion of the guide wire does not have directionality, and the operability can be favorably maintained.

[Embodiment] FIG. 1 shows an embodiment of a medical guide wire according to the present invention. Note that, for convenience, the drawing shows only the distal end portion of the guide wire in an enlarged manner.

The guide wire 11 has a metal wire body 12, and a tip portion 12a of the wire body 12 is formed in a tapered shape. One end of a tubular metal mesh 15 having a relatively small diameter is welded to almost the top of the tip portion 12a. Since the metal mesh 15 is welded so as to cover the top portion of the tip portion 12a of the wire body 12, a strong connection is made. Further, a metal coil 14 in which a fine wire is wound tightly is arranged on the outside of the metal mesh 15, and one end of the coil 14 is welded so as to cover the tip portion 12a of the wire body 12. The other ends of the metal mesh 15 and the coil 14 are
Both are melted and fixed to form a curved head 13. The head portion 13 slides well during insertion of the guide wire 11 into the tubular organ to prevent tissue damage. The material of the wire main body 12, the metal coil 14, and the metal mesh 15 needs to be a metal that does not corrode when inserted into the body, and for example, stainless steel is preferably used. Also,
As the metal mesh 15, various shapes such as a cylindrical shape, a plate shape, and a string shape can be used, but a cylindrical shape is particularly preferable.

In the guide wire 11, the metal mesh 15 prevents the metal coil 14 from expanding. Further, both of the metal mesh 15 and the metal coil 14 have their base end portions welded to the tip end portion 12a of the wire body 12 with a wide contact area, and the metal mesh 15 is flexible and foldable. Since it is strong against a load such as bending and pulling, it is possible to prevent the welded portion of the tip portion 12a from being broken. Furthermore, since the metal mesh 15 has uniform flexibility in all directions, the flexibility of the tip portion 12a does not have directionality,
Good operability can be maintained.

[Advantage of Invention] As described above, according to the medical guide wire of the present invention, the strength at the tip of the wire can be increased to prevent breakage and the like, and the tip is not directional and flexible. It is possible to impart operability and improve operability.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing an embodiment of a medical guide wire according to the present invention, FIG. 2 is a partial sectional view showing an example of a conventional medical guide wire, and FIG. 3 is a conventional medical guide wire. It is a fragmentary sectional view showing other examples. In the figure, 11 is a guide wire, 12 is a wire body, 12a is a tip, 13 is a head, 14 is a metal coil, and 15 is a metal mesh.

Claims (1)

[Scope of utility model registration request] 1. A metal wire having a tapered tip,
One end is welded to the tip of the wire, the other end is melted to form a curved head, and the metal coil is arranged in the metal coil and one end is welded to the tip of the wire. And a metal mesh welded to the head of the metal coil.