JP2007097662A - Medical guide wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a guide wire which has excellent visual recognizability by a fiberscope inside a body, has low frictional resistance with tubes such as a catheter and cannula, and is excellent in workability. <P>SOLUTION: In this guide wire 10, the outer periphery of a core wire is sheathed with a resin membrane having at least in part a convex/concave spiral pattern 41 classified by color in a plurality of colors. It is preferable that the depth of the convex/concave is 0.01-0.1 mm. Also, it is preferable that the spiral pattern is prepared with the pitch of 1-5/cm. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a medical guide wire used to guide the distal end of a catheter to a target location when the catheter is inserted into a tubular organ of a human body such as a blood vessel, a ureter, a bile duct, or a trachea.

  In recent years, for the inspection and treatment of human tubular organs such as blood vessels, ureters, bile ducts, and trachea, a catheter is inserted to administer contrast agents, etc., or a portion of tissue is collected with forceps through the catheter. Has been done. When inserting a catheter, a relatively thin and flexible guide wire is first inserted into the tubular organ, and after the distal end of the guide wire reaches the target location, the catheter is inserted along the outer periphery of the guide wire. The guide wire is pulled out.

  For example, in the treatment with a balloon catheter, when exchanging the balloon catheter, it is necessary to hold the guide wire so that it does not move, and the position of the tip of the guide wire is determined while imaging the inside through the fiberscope of the endoscope. Work is performed so as not to slip during the exchange of the balloon catheter.

  For this reason, if the visibility of the guide wire is poor, the position of the distal end portion of the guide wire may be displaced during the balloon catheter exchange operation, and the balloon catheter may not be placed in the target location accurately.

Therefore, various attempts have been made to improve the visibility of the guide wire with a fiberscope when the guide wire is inserted into or removed from the body. For example, in Patent Document 1 below, the guide wire is compared with the base side. A core member having a distal end portion having a small diameter, an intermediate portion continuously extending to the base side continuously from the distal end portion, and a base end portion continuing to the intermediate portion and further extending to the base side. Is coated with a synthetic resin film, and at least the synthetic resin film coated on the intermediate portion is formed with a spiral pattern, and the synthetic resin film coated on the distal end portion or the base end portion is coated. A medical guide wire having a portion where the pattern is not formed is disclosed in at least one of the synthetic resin films.
JP 2001-46508 A

  However, even the guide wire disclosed in Patent Document 1 has visibility with a fiberscope, but its effect is still insufficient.

  Further, in order to reduce the frictional resistance between the guide wire and tubes such as a catheter and cannula and improve the slipperiness, the guide wire is coated with a hydrophilic resin on the outer periphery. The slipperiness of the tube is not sufficient, and the precision of operation may be difficult due to poor insertion workability of these tubes.

  Accordingly, an object of the present invention is to provide a guide wire that is excellent in visibility by a fiberscope in the body, has low frictional resistance with tubes such as a catheter and cannula, and has excellent insertion workability.

  In order to achieve the above object, a first aspect of the present invention provides a guide wire characterized in that the outer periphery of a core wire is covered with a resin film having at least a part of an uneven spiral pattern color-coded in a plurality of colors. Is.

  According to the first invention, at least a part of the guide wire is provided with a spiral pattern that is color-coded in a plurality of colors. The direction in which the guidewires move relative to each other, the distance they move, etc. can be confirmed, and the visibility is excellent.

  In addition, since the outer periphery of the guide wire is uneven due to this spiral pattern, when used by attaching to a tube such as a catheter or cannula, the convex portion due to the spiral pattern on the outer periphery of the guide wire You will be in touch. Therefore, the contact area between the guide wire and the tubes is reduced, and the frictional resistance when inserting or removing these tubes can be reduced, so that the workability of inserting the tubes can be improved.

  According to a second aspect of the present invention, there is provided the guide wire according to the first aspect, wherein the unevenness has a depth of 0.01 to 0.1 mm.

  According to the second aspect of the present invention, the contact area between the guide wire and tubes such as a catheter and cannula can be reduced by setting the depth of the irregularities within the above range. Since the frictional resistance is reduced, the sliding property of the guide wire is improved.

  According to a third aspect of the present invention, there is provided the guide wire according to the first or second aspect, wherein the spiral pattern is provided at a pitch of 1 to 5 / cm.

  According to the third aspect, since the spiral pattern is provided at a relatively short pitch, the contact area with the tube can be reduced, and the frictional resistance can be reduced, so that the sliding property of the guide wire is improved. In addition, there are a large number of spiral patterns present in the image area observed with the fiberscope. As a result, the visibility of the traveling state of the guide wire, the moving distance, etc. is high, and the operability is excellent.

  According to the guide wire of the present invention, since it has an uneven spiral pattern that is color-coded in a plurality of colors, the guide wire moves in the direction of movement by using the spiral pattern as a marker when working with a fiberscope. In addition, the moving distance can be confirmed, the visibility with the fiberscope in the body is excellent, and the operability of the guide wire is excellent. In addition, because of this spiral pattern, at least a part of the outer periphery of the guide wire is uneven, reducing the contact area between the guide wire and the tube when used by inserting into a tube such as a catheter or cannula Therefore, the frictional resistance when inserting and removing these tubes can be reduced, and the insertion workability of the tubes can be improved.

  Hereinafter, an embodiment of the guide wire of the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 and 2, the guide wire 10 includes a core wire 20, a coil 30 attached to the outer periphery of the distal end portion 22 of the core wire 20, and a first resin film that covers the base 21 side of the core wire 20. 40 and the second resin film 50 that covers the outer periphery of the coil 30 and covers the tip portion 22 of the core wire 20.

  As shown in FIG. 2, the core wire 20 includes a base portion 21 and a distal end portion 22 having a diameter reduced from the base portion 21, and the distal end portion 22 further includes a tapered portion 22 a having a diameter reduced from the base portion 21. The diameter-reduced portion 22b extends from the tapered portion 22a, and the tip 22c.

  The distal end portion 22 can be formed by means such as machining or etching, and the shape thereof is not limited to that shown in FIG. 2, but for example, the diameter is gradually reduced from the base portion 21 to form a stepped shape. The shape may be sufficient, and is not particularly limited.

  The core wire 20 is made of a super elastic alloy such as a Ni-Ti alloy, a Ni-Ti-X (X = Fe, Cu, V, Co, etc.) alloy, a Cu-Zn-X (X = Al, Fe, etc.) alloy, etc. Alternatively, a radiopaque material made of stainless steel, piano wire, Pt, Ti, Pd, Rh, Au, W, and alloys thereof is preferably used.

  A coil 30 is disposed on the outer periphery of the distal end portion 22 of the core wire 20. In this embodiment, the proximal end portion 31 of the coil 30 is joined to a portion in the middle of the tapered portion 22a by a brazing material 60, and the distal end portion 32 of the coil 30 is brazed with the most distal end 22c of the core wire 20. Joined by a material 61.

  As the material of the wire material forming the coil 30, the same material as the material of the core wire 20 can be used.

  As shown in FIG. 3, the core wire 20 and / or the coil 30 are made of a superelastic alloy b disposed in the outer periphery in the form of a tube and a radiopaque material a disposed in the center thereof. Are particularly preferable. In this case, the superelastic alloy b disposed on the outer periphery and the radiopaque material a disposed on the center portion are separated and can be relatively moved in the axial direction even if they are integrated. May be.

  As the radiopaque material a disposed in the central portion, Au, Pt, Ag, Bi, W, or an alloy containing these metals is used, and as the superelastic alloy b disposed on the outer periphery, Ni-Ti-based shape memory alloys and the like are preferably used. Further, the relationship between the diameter X of the radiopaque material a disposed at the center in FIG. 6 and the diameter Y of the wire is such that the cross-sectional area of the radiopaque material a disposed at the center is crossed by the wire. It is preferable to set it in a range of 10 to 40% with respect to the area.

  Since the wire is made of the radiopaque material a disposed at the center and the superelastic alloy b disposed at the outer periphery, the wire can be flexibly adapted to bend at the bent portion of the tubular organ. And the visibility which can visually recognize the position of the coil 30 by radiography such as an X-ray fluoroscopic camera.

  A first resin film 40 is coated on the base 21 side of the core wire 20. In this embodiment, the first resin film 40 partially covers up to the middle of the tapered portion 22a of the core wire 20.

  Further, a spiral pattern 41 is formed along the axial direction of the first resin film 40, whereby the first resin film 40 is color-coded into a plurality of colors, and a fiberscope 3 (FIG. 4) described later. In this manner, the image of the guide wire 10 is displayed on the monitor, and the visibility during operation is improved, and the surface of the first resin film 40 is formed with irregularities so as to be in contact with tubes such as a catheter and cannula. The area is reduced and the sliding property of the guide wire is improved.

  For example, the first resin film 40 is formed by forming two-color heat-shrinkable resin materials from a rotating cylindrical die at the same time by changing the extrusion pressure of each resin material to form an uneven spiral pattern. The resin tube 40 is directly coated on the outer periphery on the base end 21 side of the core wire 20 by molding the resin tube and covering the outer periphery on the base 21 side of the core wire 20 with heat shrinkage, or by the extrusion molding method. It can form by the method of making it.

Examples of the material of the first resin film 40 include polytetrafluoroethylene (PTFE), perfluoroalkoxy resin (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and tetrafluoroethylene- Fluorine resin such as ethylene copolymer (ETFE), or synthetic resin such as polyurethane, nylon elastomer, polyether block amide, polyethylene, polyvinyl chloride, vinyl acetate, etc., such as polytetrafluoroethylene (PTFE) A fluororesin is preferred. Further, in the resin material, BaSO 4, _Bi, powder may be a further contain radiopaque material such as _W.

  The depth of the unevenness formed by the spiral pattern 41 needs to be 0.01 to 0.1 mm, and preferably 0.02 to 0.03 mm. If it is less than 0.01 mm, the effect of reducing the frictional force with tubes such as catheters and cannulae is poor, and the sliding property of the guide wire is insufficient. If it exceeds 0.1 mm, the outer diameter of the guide wire increases. For this reason, the insertion into the body is reduced.

  Moreover, it is preferable that the spiral pattern 41 is provided with the pitch of 1-5 / cm, and 2-3 / cm is especially preferable. By providing the spiral pattern at the above pitch, the guide wire is excellent in visibility with a fiberscope or the like, and has low frictional resistance with tubes such as a catheter and cannula, and can have a good sliding property.

  Moreover, 450-5000 mm is preferable and, as for the length of the range which attaches the spiral pattern 41, 450-4500 mm is more preferable. If it is less than 450 mm, the range in which position confirmation and distance measurement can be performed is shortened by the fiber scope, and if it exceeds 5000 mm, a spiral pattern is added to the part that is not used for confirmation by the fiber scope, resulting in high manufacturing costs. It is just uneconomical.

  Further, the spiral pattern 41 is preferably formed at least in a range of a position 30 mm away from the most distal end portion 11 of the guide wire 10 to a position separated by 500 mm, and a position away from the most distal end portion 11 of the guide wire 10 by 50 mm. More preferably, it is formed at least in the range of a position separated by ˜500 mm. As a range used for confirmation by the fiberscope, a range from a position 30 mm away from the most distal end portion 11 of the guide wire 10 to a position 500 mm away is the most frequently used portion.

  A second resin film 50 is coated on the end portion 22 side of the core wire 20.

The second resin film 50 is made of, for example, polytetrafluoroethylene (PTFE), perfluoroalkoxy resin (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-ethylene copolymer. It is made of fluorine resin such as polymer (ETFE), or synthetic resin such as polyurethane, nylon elastomer, polyether block amide, polyethylene, polyvinyl chloride, vinyl acetate, etc. It is preferably formed of a resin, and a powder such as BaSO ₄ , Bi, or W may be contained to form a radiopaque material.

  Hydrophilic resins such as polyvinyl pyrrolidone, polyethylene glycol, and methyl vinyl ether maleic anhydride copolymer are provided on the outer periphery of the first resin film 40 and the second resin film 50 in order to provide slipperiness and thrombus adhesion prevention. Is preferably coated.

  Next, an example of the manufacturing method of the guide wire 10 of this invention is demonstrated.

  First, the coil 30 is disposed on the outer periphery of the distal end portion 22 of the core wire 20, and the proximal end portion side 31 of the coil 30 is fixed to a middle portion of the taper portion 22 a of the core wire 20 with a brazing material. The distal end side 32 is fixedly bonded to the leading edge 22 c of the core wire 20 with the brazing material 61.

  Then, a first tube which is formed with an inner diameter slightly larger than the outer diameter of the base portion 21 of the core wire 20 and whose end face is cut and aligned by a cutter or the like is inserted from the base 21 side of the core wire 20. The distal end portion is pushed to the proximal end of the distal end 22 of the core wire 20.

  Then, the first tube is heated and contracted by a heating means such as a heater, so that the base film 21 is covered with the first film 40.

  Next, an acrylic or epoxy adhesive such as cyanoacrylate is applied to the inner periphery and end face of the first resin film 40, and the first end 22 of the core wire 20 and the outer periphery of the coil 30 are applied to the outer periphery of the first resin film 40. The second tube to be the resin film 2 is inserted. The second tube is swollen in advance with a solvent such as methyl ethyl ketone (MEK).

  Then, by drying the solvent with the second tube inserted and shrinking the second tube, the proximal end of the second tube is fixed to the distal end of the first resin film 40 via the adhesive, and The inner periphery of the second tube is also fixed to the outer periphery of the core wire 20 and the coil 30, and the second resin film 50 is covered on the tip 22 side of the core wire 20.

  Next, an example of a method of using the guide wire 10 of the present invention will be described with reference to FIG. FIG. 4A is an explanatory view showing the usage state of the guide wire, and FIG. 4B is an explanatory view showing the usage state of the fiberscope.

  The guide wire 10 is inserted into the bile duct 1 or the like through the duodenum, and is used to treat a lesion site such as the stenosis 2 or the like.

  First, the balloon catheter 4 is inserted along the outer periphery of the fiberscope 3, the guide wire 10 of the present invention, and the guide wire 10 through a plurality of lumens formed in a tube-shaped transport tool (not shown), and the first resin tube Using the spiral pattern 41 of 40, while confirming the image from the fiberscope 3 with an endoscope, the carrier is inserted into the duodenum through the oral cavity and further introduced into the bile duct 1.

  When the guide wire 10 reaches the target stenosis 2, the balloon catheter 4 is inserted along the outer periphery of the guide wire 10. When the guide wire 10 is inserted up to the stenosis 2, the guide wire 10 is pulled out and the physiological saline is extracted. The balloon of the balloon catheter is inflated with water or the like, and the stenosis 2 is pressed from the inside to widen the stenosis 2. At this time, since the contact pattern with the balloon catheter is reduced due to the spiral pattern 41 having an uneven shape, the guide wire 10 and the balloon catheter 4 are highly slidable and the balloon catheter 4 is easily inserted.

  Hereinafter, the present invention will be described in more detail by way of examples.

Example 1
The outer periphery of the core wire 20 is covered with a resin tube having a spiral pattern 41 made of polytetrafluoroethylene (PTFE) and having a concave and convex shape with a depth of 0.01 mm and color-coded in two colors at a pitch interval of 1 / cm. The resin tube was coated on the outer periphery of the core wire 20 by thermal contraction by the above, and the guide wire of Example 1 was produced.

(Example 2)
Example except that the resin tube is made of polytetrafluoroethylene (PTFE) and has a spiral pattern 41 having a depth of 0.02 mm, which is color-coded in two colors, at a pitch interval of 5 / cm. In the same manner as in Example 1, a guide wire of Example 2 was produced.

(Test example)
Fix the part 10cm from the tip of the guide wire and attach it to a load measuring instrument (trade name: “DIGITAL FORCE GAUGE” model number: “AD-4935-200N” manufacturer: “A & D”), with a pulling speed of 500 mm / min. The cannula (trade name “Zemex ERCP Catheter” manufactured by Nippon Zeon Co., Ltd.) was inserted at a stroke length of 10 cm, and the maximum load (N) at the time of cannula insertion was measured for each guide wire of Examples 1 and 2. The results are shown in Table 1.

  As shown in Table 1, by reducing the pitch interval of the uneven spiral pattern, the load during cannula insertion was reduced, and the frictional resistance could be reduced.

It is explanatory drawing which shows one Embodiment of the guide wire of this invention. It is sectional drawing in the front-end | tip part of the guide wire. It is explanatory drawing which shows the other example of the wire which comprises the core wire and coil of the same guide wire. (A) It is explanatory drawing which shows the use condition of the guide wire, (b) It is explanatory drawing which shows the use condition by the fiberscope of the guide wire.

Explanation of symbols

10: guide wire 20: core wire 30: coil 40: first resin film 41: spiral pattern 50: second resin film 60, 61: brazing material

Claims (3)

  A medical guide wire characterized in that the outer periphery of a core wire is covered with a resin film having at least a part of an uneven spiral pattern color-coded in a plurality of colors.   The medical guide wire according to claim 1, wherein the unevenness has a depth of 0.01 to 0.1 mm.   The medical guide wire according to claim 1 or 2, wherein the spiral pattern is provided at a pitch of 1 to 5 / cm.