JP2002017864A - Guide wire for medical use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a guide wire for medical use which has excellent visibility by a fiberscope within a body and is easy to be inserted into the body. SOLUTION: The outer periphery of a core consisting of twisted wires 11a and 11b is coated with a transparent resin layer 12, and the outer periphery of the layer 12 is coated with a hydrophilic resin layer 13 to form the guide wire 10. At least one wire 11a has a color different from that of the other wire 11b, thereby a spiral pattern is formed at the core 11. Since the layer 12 prevents the wires 11a and 11b from being frayed, the guide wire is safe, and sliding property is given by the layer 13. Furthermore, the spiral pattern formed at the core 11 is visually recognized through the layer 12 and the layer 13, thereby visibility by the fiberscope becomes excellent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a medical guidewire used for guiding a distal end of a catheter to a target site when the catheter is inserted into a tubular organ of a human body such as a blood vessel, a ureter, a bile duct, and a trachea. .

[0002]

2. Description of the Related Art In recent years, for examination and treatment of tubular organs of the human body such as blood vessels, ureters, bile ducts, and trachea, a catheter is inserted to administer a drug such as a contrast medium, or a catheter having a balloon at the tip is used. Insertion is used to dilate a stenosis of a tubular organ. When inserting a catheter, a relatively thin and flexible guidewire is first inserted into the tubular organ, and the distal end of the guidewire reaches a target location, and then the catheter is inserted along the outer periphery of the guidewire. .

As an example of a treatment method using a catheter, FIG. 9 shows a method of dilating an obstruction of a bile duct. In FIG. 9, 1 is a duodenum, 2 is a bile duct, and 3 is an endoscope. The endoscope 3 has a main body tube 4 having a plurality of lumens, and a fiberscope 5 inserted into one of the lumens. The distal end 6 of the fiberscope 5 is disposed so as to project laterally from the distal end of the main body tube 4 and to be directed inside the bile duct 2. Also,
The guide wire 7 and the balloon catheter 8 are inserted through another lumen formed in the main body tube 4.

[0004] In this treatment, first, a guide wire 7 is inserted through an endoscope 3 inserted into the duodenum 1, the distal end of the guide wire 7 is guided from the duodenum 1 into the bile duct 2, and further, a stenosis portion of the bile duct 2. Lead to 2a. In this state, the balloon catheter 8 is inserted so as to cover the outer periphery of the guide wire 7, and the distal end of the balloon catheter 8 is guided to the stenosis portion 2a. Thereafter, the balloon 9 attached to the outer periphery of the distal end portion of the balloon catheter 8 is inflated by a conventional method,
By rubbing the stenosis 2a with the balloon 9, the stenosis 2
a is extended.

However, since the stenosis 2a cannot be sufficiently expanded in one operation, the balloon catheter 8 is often used.
Is removed, another balloon catheter having a larger diameter balloon is inserted again, and the stenosis portion 2a is rubbed again with a larger inflated balloon to expand the balloon.

As described above, when replacing the balloon catheter, it is necessary to hold the guide wire 7 so as not to move when the first balloon catheter 8 is pulled out. Even if the inside is imaged through the scope 5, it is difficult to visually recognize whether the guide wire 7 is moving, and the position of the distal end of the guide wire 7 may be shifted during the replacement operation of the balloon catheter.

In order to solve such a problem, US Pat. No. 5,379,779 discloses that a tube having a spiral pattern is coated over the entire outer periphery of a core material of a guide wire, and the guide wire is moved by the spiral pattern. There is disclosed a technique for making it easier to visually recognize an image with an endoscope.

[0008]

However, in the guide wire described in the above-mentioned U.S. Pat. No. 5,379,779, the material of the resin forming the tube for covering the core material of the guide wire has a spiral pattern. However, there is a possibility that the guide wire cannot be sufficiently inserted and the guide wire cannot be easily inserted. It is also conceivable to improve the slipperiness by forming a hydrophilic resin layer on the outer periphery of the resin layer having a spiral pattern. However, since the material of the resin layer having the spiral pattern is limited, a hydrophilic layer is formed on the outer periphery. There was a problem that it was difficult to attach the resin.

Accordingly, it is an object of the present invention to provide a medical guidewire which is excellent in visibility by a fiberscope in a body and is easily inserted into the body.

[0010]

Means for Solving the Problems In order to achieve the above object, a first aspect of the present invention is to provide a core material comprising two or more stranded wires, wherein the outer periphery of the core material is covered with a transparent resin layer, A medical guidewire is provided, wherein at least one of the strands has a different color from other strands.

According to the first aspect, at least one of the strands constituting the core has a different color from the other strands, so that a spiral pattern is formed on the core. In addition, since the outer periphery of the core is covered with a transparent resin layer, it prevents fraying of stranded wires, smoothes the outer periphery, and allows the spiral pattern formed on the core to be visually recognized through the transparent resin layer. Is done. Therefore, even when inserted into the body, there is no risk of the core material fraying, so that the safety is excellent and the visibility by the fiber scope can be excellent. In addition, since a spiral pattern is formed on the core material and a resin layer for forming the spiral pattern is not required, the material of the resin layer covering the core material is not limited, and the core layer is coated with a hydrophilic resin and inserted into the body. An easy guidewire can be manufactured at low cost.

According to a second aspect of the present invention, in the first aspect, the stranded wire provides a medical guidewire in which two or more adjacent stranded wires have a different color from other stranded wires. is there.

According to the second aspect of the invention, the width of the spiral pattern formed on the core material can be widened, so that the visibility of the guide wire by the spiral pattern can be improved.

According to a third aspect of the present invention, in the first or second aspect, the color of the stranded wire is changed at a predetermined position in a length direction of the core material. A medical guidewire is provided.

According to the third aspect of the present invention, it is possible to easily understand how much the guide wire has been inserted from a change in the pattern interval at a predetermined position even in a limited viewing range such as a fiberscope.

[0016]

1 to 3 show an embodiment of a medical guidewire according to the present invention. 1 is a perspective view of a guide wire, FIG. 2 is a cross-sectional view of the guide wire,
FIG. 3 is a longitudinal sectional view of the guide wire.

The guide wire 10 comprises a core 11 made of a stranded wire, a resin layer 12 covering the core 11, and a hydrophilic resin layer 13 coated on the outer surface of the resin layer 12. ing. The distal end A of the core material 11 is gradually reduced in diameter toward the forefront, and when inserted into a tubular organ,
The flexibility is provided so as not to damage the inner wall of the tubular organ.

The core material 11 is composed of three stranded wires 11a, 11b and 11b which are helically twisted. And 1
The stranded wire 11a has a color different from that of the other two stranded wires 11b, whereby the core material 11 has a spiral pattern extending in the axial direction. In addition, as a method of coloring the stranded wire, for example, a method of baking the wire material or coating a colored resin is adopted. In this embodiment, a marker 15 made of a radiopaque metal coil is attached to the tip of the core material 11.

The stranded wires 11a and 11b are preferably made of a superelastic material or an elastic material. Here, stainless steel, piano wire, or the like is preferably used as the elastic material. Further, as the superelastic material, Ni-Ti alloy, Cu
-Zn-X (X = Al, Fe, etc.) alloy, Ni-Ti-X
(X = Fe, Cu, V, Co, etc.) alloy is preferably used.

It is widely known that the Ni-Ti alloy and the like have a shape memory effect and a superelastic (pseudoelastic) effect as a shape memory alloy. Of these, those with superelastic (pseudoelastic) effects are different from ordinary metallic materials, which undergo permanent deformation due to deformation strain exceeding the yield point. It returns to its original shape without it, and has great return characteristics against torsion and bending. For this reason, it is suitable as a core material of a guide wire, and a temperature condition at which a superelastic (pseudoelastic) effect is exhibited is preferably set to a human or animal body temperature or lower. Note that superelasticity (pseudoelasticity) is described in JIS H 7001 issued by the Japan Standards Association.

Further, the stranded wires 11a and 11b are not necessarily made of the same material, but may be made of two or three or more kinds. For example, a wire made of a superelastic material and a wire made of an elastic material such as stainless steel may be combined. As described above, by combining a plurality of types of wires, a superelastic effect can be provided while imparting appropriate rigidity.

The distal end portion A of the core material 11 is gradually reduced in diameter toward the distal end by mechanical polishing. In addition, the colors of the stranded wires 11a, 11b, and 11c at the distal end portion A have disappeared by polishing. The method of reducing the diameter of the distal end portion A is not limited to mechanical polishing. For example, etching or a method of tapering the stranded wires 11a and 11b in advance may be employed. The length A of the reduced diameter tip portion varies depending on the treatment target, but is preferably about 30 to 500 mm. The diameter of the core material 11 is 0.2 to
It is appropriately set within a range of about 2.0 mm according to the purpose.

The outer periphery of the core material 11 is formed of stranded wires 11a, 11b
Is covered with a resin layer 12 so as not to fray and to smooth the outer peripheral shape. Furthermore,
The outer periphery of the resin layer 12 is covered with a hydrophilic resin layer 13.

The resin layer 12 and the hydrophilic resin layer 13 are not particularly limited as long as they are transparent so that the spiral pattern of the core material 11 can be visually recognized from the outside. The resin layer 12 is, for example, urethane resin. Preferably adopted, hydrophilic resin layer 1
The _{3, -OH, -CONH 2, -COOH} , -N
A resin having a hydrophilic group, such as H ₂ , —COO ⁻ , or —SO ³⁻ , having a functional group that can be bonded to the surface of the resin layer 12 is preferably used.

The marker 15 is for confirming the position of the guide wire 10 by confirming its position on an X-ray monitor. For example, gold, platinum, silver,
It is composed of a radiopaque material such as bismuth, tungsten, or an alloy containing these metals. Further, as a means for fixing the metal coil to the core material 11, means such as welding with a brazing material, adhesion with an adhesive, or the like can be adopted. Note that, in the core material 11, the resin layer 12 and the hydrophilic resin layer 13 are also formed on the portion where the marker 15 is mounted, similarly to the other portions.

Since the guide wire 10 has the above configuration, the transparent resin layer 12 and the hydrophilic resin layer 1
Through 3, the spiral pattern formed on the core material 11 is visually recognized. Therefore, when inserted into the body, the movement of the guidewire 10 can be easily recognized by an endoscope or the like, and work such as removal of the catheter while preventing movement of the guidewire 10 can be facilitated.

Further, since the surface of the guide wire 10 is provided with the hydrophilic resin layer 13, it exhibits extremely good sliding properties when wet with water or body fluid. For this reason, it is possible to improve the slipperiness for the tubular tissue in the body and the slipperiness for the catheter and the like.

Further, the core material 11 is made of stranded wires 11 of different colors.
a and 11b to form a spiral pattern and eliminate the need for a resin layer for providing the spiral pattern, so that the material of the resin layer 12 covering the core material is not limited, and the outer periphery of the hydrophilic resin layer 13 Can be formed easily.

4 to 6 show another embodiment of the medical guidewire according to the present invention. 4 is a perspective view of the guide wire, FIG. 5 is a transverse sectional view of the guide wire, and FIG. 6 is a longitudinal sectional view of the guide wire. In each of the embodiments described below, substantially the same parts as those described in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The guide wire 20 has basically the same shape as the guide wire 10 in the above embodiment. That is, the guide wire 20 includes a core 21 made of a stranded wire, the resin layer 12 covering the core 21, and the hydrophilic resin layer 13 covering the outer periphery of the resin layer 12.

However, in this guide wire 20,
The core member 21 is formed by spirally twisting eight stranded wires 21b and 21c, which are thinner than the core wire 21a, around the core wire 21a arranged at the center. Twisted wires 21b, 21c
Of the four adjacent stranded wires 21b and the other adjacent stranded wires 21c have different colors, and
Is formed with a spiral pattern. In addition, by changing the color of the adjacent four stranded wires, the width and the interval of the spiral pattern can be increased to make the spiral pattern more visible. However, the combination of the stranded wires for changing the color is not limited to four, and can be appropriately changed according to a desired spiral pattern width or interval.

The stranded wires 21b and 21c are previously reduced in diameter toward the distal end, and as a result, as shown in FIG. 6, the interval between the spiral patterns is set to be narrower toward the distal end.

FIG. 7 shows still another embodiment of the medical guidewire according to the present invention. This guide wire 30 is the same as the guide wire 10 of the above-described embodiment.
A plurality of markers 15 are attached to the front end portion A of the core material 11 at predetermined intervals.

According to the guide wire 30, since the markers 15 made of an X-ray opaque metal coil are mounted at predetermined intervals, when the guide wire 30 is inserted into the body, the markers are displayed on the X-ray monitor. By confirming the position of 15, the tip of the guide wire 30 can be reliably grasped, and the portion where the marker 15 is attached at a predetermined interval functions as a scale (measure). The length and the like of the stenosis can be easily grasped.

FIG. 8 shows still another embodiment of the medical guidewire according to the present invention. The guide wire 40 includes three stranded wires 41 a and 41 helically twisted.
b, 41c.

The guide wire 4 is attached to one strand 41a.
0 is given a specific color over the entire length, and the other stranded wire 41b is given a color different from that of the stranded wire 41a over the entire length of the guide wire 40, and the remaining stranded wire 41b is further colored. Only one portion of the single stranded wire 41c located at the intermediate portion B of the guide wire 40 has the same color as the stranded wire 41a, and the remaining portion has the same color as the stranded wire 41b.

The tip A of the core 41 is gradually reduced in diameter toward the tip by mechanical polishing.
The colors of 1a, 41b and 41c have disappeared by polishing.
Also, a core material 41 composed of the stranded wires 41a, 41b, 41c
Outside, a resin layer 12 and a hydrophilic resin layer 13 are formed. Furthermore, a marker 15 made of a radiopaque metal coil is attached to the tip of the core material 41.

According to the guide wire 40, a spiral pattern is formed by the difference in color between the three strands 41a, 41b, 41c. At this time, at the distal end portion A, the colors of the stranded wires 41a, 41b, 41c disappear by polishing, and at the proximal end portion C, the stranded wires 41a of a specific color and the stranded wires 41b, 41c of different colors from the stranded wires 41a, 41c. Spiral pattern is formed, and in the intermediate portion B, the stranded wires 41a and 41c of specific colors are formed.
And a helical pattern composed of stranded wires 41b of different colors.

For this reason, the spiral pattern of a specific color applied to the stranded wire 41a has no color at the distal end portion A, has a narrow and thick spiral at the intermediate portion B, and has a wide and narrow spiral at the proximal end portion C. Therefore, it is possible to easily grasp how far the guide wire 40 has been inserted by the change in these patterns.

[0040]

As described above, according to the medical guidewire of the present invention, at least one of the stranded wires constituting the core has a different color from the other stranded wires. A spiral pattern is formed. In addition, since the outer periphery of the core is covered with a transparent resin layer, it prevents fraying of stranded wires, smoothes the outer periphery, and allows the spiral pattern formed on the core to be visually recognized through the transparent resin layer. Is done. Therefore, even when inserted into the body, there is no risk of the core material fraying, so that the safety is excellent and the visibility by the fiber scope can be excellent. In addition, since a spiral pattern is formed on the core material itself, and a resin layer for forming the spiral pattern is not required, the material of the resin layer covering the core material is not limited. It can be made of a material that easily adheres.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a medical guidewire according to the present invention.

FIG. 2 is a cross-sectional view of the medical guidewire.

FIG. 3 is a longitudinal sectional view of the medical guidewire.

FIG. 4 is a perspective view showing another embodiment of the medical guidewire according to the present invention.

FIG. 5 is a cross-sectional view of the medical guidewire.

FIG. 6 is a longitudinal sectional view of the medical guide wire.

FIG. 7 is a longitudinal sectional view showing still another embodiment of the medical guidewire according to the present invention.

FIG. 8 is a longitudinal sectional view showing still another embodiment of the medical guidewire according to the present invention.

FIG. 9 is an explanatory diagram showing an example of a treatment method for dilating a stenotic portion of a bile duct.

[Explanation of symbols]

10, 20, 30, 40 Medical guide wire 11, 21, 41 Core material 11a, 11b, 21b, 21c, 41a, 41b, 4
1c stranded wire 12 resin layer 13 hydrophilic resin layer 15 marker

Claims (3)

[Claims] 1. A core material comprising two or more stranded wires,
A medical guide wire, wherein an outer periphery of the core material is covered with a transparent resin layer, and at least one of the stranded wires has a color different from other stranded wires. 2. The medical guidewire according to claim 1, wherein two or more adjacent stranded wires of the stranded wire have a different color from other stranded wires. 3. The medical guidewire according to claim 1, wherein a color of the stranded wire changes at a predetermined position in a length direction of the core material.