JPH07275366A - Guide wire - Google Patents

Abstract

PURPOSE:To provide a catheter guide wire whose tip is highly contrasted against X-rays even if the diameter of the guide wire is made thinner, and that allows a catheter to be easily guided to an objective position. CONSTITUTION:This guide wire is composed of a core wire 2 which integrates a main body 2a with high rigidity with a tip 2b which is smaller than the main body 2a in diameter and is less than the main body 2a in rigidity, a portion 3 which is highly contrasted against X-rays at the tip of the core wire 2, a synthetic resin film 4 which covers the core wire 2 with the portion 3 which is highly contrasted against X-rays, and a lubricant substance fixed on the surface of the synthetic resin film 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a guide wire used for introducing a catheter into a necessary part of a human body for treatment or examination.

[0002]

2. Description of the Related Art In recent years, catheters have been introduced into blood vessels for examination and treatment of heart diseases and the like. When introducing such a catheter into a target site in the body, a guide wire is inserted into the catheter, the tip of the guide wire is slightly projected from the tip of the catheter, and the guide wire guides the catheter to the target site. .

As such a guide wire for a catheter, for example, JP-A-60-7862 and JP-A-60-62
There is one disclosed in Japanese Laid-Open Patent Publication No. 63066. These guide wires have an inner core formed of a superelastic metal body at least at the tip end, and the entire inner core is covered with a synthetic resin. This guide wire is excellent in the guide property of the catheter due to the high flexibility and the restoring property of the tip portion.

[0004]

The guide wire described above has an extremely excellent effect in terms of guiding the catheter. However, in the above guide wire, unlike the conventional guide wire, the inner core is not covered with a metal wire such as a coil, but the inner core is only covered with a synthetic resin. It may be possible to include an X-ray contrast substance in the synthetic resin coated, but the content is limited due to deterioration of the physical properties of the synthetic resin film, etc.
The radiographic function was not very high. In particular, the inner core formed of a metal body has a thinner tip, so that there is a problem that the X-ray contrast property of the tip is particularly poor.

Recently, it has been considered to introduce a catheter into a thinner blood vessel, for example, an internal blood vessel of the brain, a blood vessel forming a kidney, etc., and the catheter has a smaller diameter, and a guide wire is also provided. Also, it is necessary to reduce the diameter. For this reason, in the guide wire of the type in which the inner core is coated with the synthetic resin, the X-ray contrast property of the tip portion is further deteriorated,
It is expected that it will be difficult to introduce the catheter into the target site.

Therefore, according to the present invention, even if a guide wire having a smaller diameter is formed, the distal end portion thereof has a high X-ray contrast function, and the catheter can be easily introduced into a target site. It provides a guide wire for use.

[0007]

Means for Solving the Problems To achieve the above object, there is provided an inner core integrally formed with a main body having high rigidity and a tip having a smaller diameter and lower rigidity than the main body. From a high X-ray contrast part provided at the tip of the core, a synthetic resin film encapsulating the inner core provided with the high X-ray contrast part, and a lubricating substance fixed to the surface of the synthetic resin film. It is a guide wire.

The high X-ray contrast section is, for example, a metal annular member fixed to the tip of the inner core and having a high X-ray contrast property. The annular member is preferably a coil or a pipe-shaped member. Also, the high X
The line contrast part may be, for example, a high X-ray coated on the tip of the inner core.
It is a metal layer having a line contrast property. And the inner core is
It is preferably formed of a super elastic metal. Further, the coiled high X-ray contrast material is gold, platinum, lead,
It is preferably formed of any one of silver, bismuth, and tungsten. Further, what achieves the above-mentioned object is an inner core consisting of a main body part and a tip part formed so that the diameter becomes gradually smaller toward the tip, and a high X-ray imaging provided at the tip of the inner core. Section and a synthetic resin coating for encapsulating the inner core provided with the high X-ray contrast section in a close contact state, and the surface of the synthetic resin coating is a guide wire having lubricity when wet. . Further, what achieves the above-mentioned object is an inner core consisting of a main body part and a tip part formed so that the diameter becomes gradually smaller toward the tip, and a coiled height X provided at the tip of the inner core. And a synthetic resin coating for encapsulating the inner core provided with the high X-ray contrast portion in a close contact state, and the surface of the synthetic resin coating is a guide wire having antithrombogenicity. is there.

An embodiment of the guide wire of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of an embodiment of the guide wire of the present invention. Guide wire 1 of the present invention
Is an inner core 2 in which a body portion 2a having high rigidity and a tip portion 2b having a smaller diameter than the body portion 2a and having low rigidity are integrally formed.
And a high X-ray contrast section 3 provided at the tip of the inner core 2,
It is composed of a synthetic resin coating 4 which encloses the entire inner core 2 provided with a line contrast part 3 and a lubricating substance fixed to the surface of the synthetic resin coating.

An embodiment of the guide wire of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of an embodiment of the guide wire of the present invention, and FIG. 2 is an enlarged sectional view taken along the line II of FIG.

The guide wire 1 of the present invention comprises an inner core 2 integrally formed with a highly rigid main body portion 2a and a distal end portion 2b having a smaller diameter than the main body portion 2a and having a low rigidity, and a distal end of the inner core 2. And a synthetic resin coating 4 having a substantially uniform outer diameter that covers the entire inner core 2 provided with the high X-ray contrast part 3.

The guide wire of the present invention will be described with reference to FIGS. 1 and 2. Inner core 2 of guide wire 1
Has a body portion 2a and a tip portion 2b, and is integrally formed of superelastic metal. And the tip 2b
Are formed such that the diameter gradually decreases from the tip of the main body 2a toward the tip. By having such a small diameter, the rigidity is lower than that of the main body. In this way, by gradually reducing the diameter of the tip of the inner core,
When force is applied to the tip, the tip gradually bends, improving operability.

As the inner core 2, a TiNi alloy containing 49 to 58 atomic% Ni and Cu containing 38.5 to 41.5 wt% Zn-
Zn alloy, 1-10 wt% X Cu-Zn-X alloy (X
= Be, Si, Sn, Al, Ga), 36 to 38 atomic%
A super elastic metal body such as a Ni-Al alloy of Al is preferably used. The above TiNi alloy is particularly preferable.

The outer diameter of the main body portion 2a of the inner core 2 is
0.10 to 1.00 mm, more preferably 0.15 to
The length is 0.40 mm and the length is 1000 to 4000 m.
m, more preferably 1500-3000 mm, buckling strength (yield stress under load) is 30-100 Kg / mm
² (22 ° C.), more preferably 40 to 55 Kg / mm ² ,
Restoration stress (yield stress at unloading) is 20-80Kg / m
m ² (22 ° C.), more preferably 30 to 35 Kg / mm ²
Is.

The outer diameter of the tip portion 2b of the inner core 2 is 0.
03-0.15 mm, more preferably 0.05-0.
10 and the length is 10 to 300 mm, preferably 50
The bending load is 0.1 to 10 g, preferably 0.3 to 6.0 g, and the restoring load is 0.1 to 10 mm.
g, preferably 0.3 to 6.0 g.

Further, the outer diameter of the tip portion of the inner core does not have to be the above-mentioned dimensions, but may be a part thereof. Furthermore, the restoring stress of the main body and the tip does not have to have the same value, but rather it is preferable to devise it so as to obtain appropriate physical properties at an appropriate wire diameter by changing it depending on heat treatment conditions.
That is, it is preferable to separate the heat treatment between the body and the tip so that the restoring stress of the body is large and the tip is flexible. Further, the inner core 2 is not limited to one formed by a single wire, and may be a plurality of wires that are parallel or twisted, and exhibit the above-mentioned function, that is, a stepwise or continuous change of physical properties.

In the embodiment shown in FIGS. 1 and 2, the high X-ray contrast section 3 is a metal annular member having a high X-ray contrast property fixed to the tip of the inner core 2. Is formed of a pipe-shaped member. As the metal having a high X-ray contrast property, gold, platinum, lead, silver, bismuth, tungsten and the like are preferable, and gold is particularly preferable.

The high X-ray contrast section 3 is fixed by mechanical pressure bonding to the tip of the inner core 2 or by soldering a metal plated or vapor-deposited on the tip of the inner core 2. As the metal to be plated or vapor-deposited, when the inner core 2 is a TiNi alloy, Ni or the same kind as the high X-ray contrast metal to be used is suitable, and a Cu-Zn alloy or a Cu-Zn-X alloy is preferable. In the case, Zn or the same kind as the high X-ray contrasting metal to be used is preferable, and in the case of Ni-Al alloy, Ni or the same kind as the high X-ray contrasting metal to be used is preferable. Is. And
As the solder, hard solder such as silver solder or gold solder can be preferably used.

The high X-ray contrast section 3 has an outer diameter of 0.2.
0 to 0.90 mm, preferably 0.25 to 0.40 m
m, inner diameter 0.04 to 0.16 mm, preferably 0.0
6 to 0.11 mm, length 1.00 to 10.00 mm,
It is preferably 1.5 to 4.0 mm.

Further, as the high X-ray contrast unit 3, for example,
It may be as shown in FIG. In the embodiment shown in FIG. 3, a thin wire made of a metal having a high X-ray contrast property as described above is wound around the tip of the inner core 2 in a coil shape. As the thin wire, the wire diameter is 0.02 to 0.10 m.
Those of m are preferably used. Further, the length of wrapping around is 1.0 to 10.0 mm, preferably 1.5 to 4.0 mm from the tip of the inner core.

As a method for forming such a coil-shaped high X-ray contrast part, a method of directly winding a thin wire on the inner core as described above, or a coil-shaped one formed on the tip of the inner core. A method of attachment is conceivable, and moreover, it is preferable to securely fix them to the tip of the inner core. As a method thereof, it is possible to fix them by crimping a coiled wound or attached coil from the outside. preferable. As another method, a metal for enhancing the adhesiveness with the high X-ray contrast part is plated or vapor-deposited on the tip of the inner core, and the thin wire is wound or coiled on the metal. Alternatively, it may be soldered. The coil body is generally easily deformed, and if the deformation is equal to or less than a predetermined stress value, it is elastic deformation. Therefore, if the high X-ray contrast part has such a coil shape, the flexibility of the tip of the guide wire is not significantly impeded. Further, by having such a high X-ray contrast part, the visibility of the tip of the guide wire under fluoroscopy is improved.

Further, the high X-ray contrast part 3 is made of, in addition to the above-mentioned components, a high X-ray contrast metal foil applied to and bonded to the tip of the inner core, and a high X-ray contrast metal is applied to the tip. A high X-ray contrasting metal layer may be formed by plating or vapor deposition. The above metal foil, plating and vapor deposition have a thickness of 50μ.
It is preferably m or more.

Further, as shown in FIG. 1, the synthetic resin coating 4 covering the entire inner core 2 has a substantially uniform outer diameter including the tip portion. In particular, the synthetic resin coating 4 has a substantially uniform outer diameter so that steps or the like due to the high X-ray contrast portion provided at the tip of the inner core 2 do not affect the outer surface shape of the guide wire 1.

As the synthetic resin coating 4, polyethylene,
Polyvinyl chloride, polyester, polypropylene, polyamide, polyurethane, polystyrene, fluororesin, silicone rubber or their respective elastomers and composite materials are preferably used. It is preferable that the synthetic resin coating 4 is so flexible that it does not hinder the bending of the inner core 2 and that the outer surface is a smooth surface without irregularities.

Further, the synthetic resin film 4 has an anticoagulant such as heparin, urokinase or the like, a silicone rubber, a block copolymer of urethane and silicone (registered trademark Abucosan), an antithrombogenic material such as a hydroxyethylmethacrylate-styrene copolymer. May be coated to provide a surface having antithrombotic properties. Further, by forming the synthetic resin coating film 4 with a resin having a low friction surface such as a fluororesin, and by applying a lubricating liquid such as silicone oil to the outer surface of the synthetic resin coating film 4, the frictional property of the guide wire 1 can be improved. It may be lowered.

Further, it is preferable to mix a fine powdery X-ray contrast substance with a simple metal or a compound such as Ba, W, Bi and Pb into the synthetic resin forming the synthetic resin coating film 4. By doing so, it becomes easy to confirm the entire position of the guide wire 1 being introduced into the blood vessel. As described above, the synthetic resin coating 4 preferably has a substantially uniform outer diameter. The term “substantially uniform” is not limited to being completely uniform, and the tip may have a slightly smaller diameter. In this way, by making the distal end portion substantially uniform, it is possible to reduce damage that the distal end of the guide wire may give to the inner wall of the blood vessel.

The outer diameter of the synthetic resin coating is 0.25 to 1.0.
4 mm, preferably 0.30 to 0.64 mm, and the thickness of the inner core 2 on the main body portion 2a is 0.25 to 1.04 mm, preferably 0.30 to 0.64 mm.

Further, it is preferable that the synthetic resin coating 4 is adhered to the inner core 2 by a synthetic resin in a close contact state, and is fixed also at the front end portion and the base end portion of the inner core 2. In addition, the synthetic resin coating 4 is formed of a hollow tube, and the inner core 2
The inner core 2 may be fixed to the inner core 2 by adhesion or melt molding at the distal end portion and the proximal end portion or at an appropriate portion of the inner core. The tip of the guide wire 1 (tip of the synthetic resin coating 4) prevents damage to the blood vessel wall, and further the guide wire 1
In order to improve the operability, the curved surface is preferably a hemispherical shape as shown in FIG.

Further, a lubricating substance is fixed on the surface of the synthetic resin film 4. Lubricant refers to a substance that has lubricity when wet. Specifically, there are water-soluble polymer substances or their derivatives. The lubricating substance is fixed to the surface of the synthetic resin by covalent bond or ionic bond. Then, the lubricant material is a polymeric material having no crosslinked principle chain, -OH, -CONH _2, -
It has a hydrophilic group such as COOH, —NH ₂ , —COO ⁻ , and —SO ^{3 −} . Furthermore, the lubricating substance contains water when wet (for example, when it comes into contact with blood) to exhibit lubricity.

Such a lubricating substance is used as a guide wire 1
By fixing to the synthetic resin coating 4 which is the outer surface of
When the catheter is introduced, the friction between the inner wall of the catheter and the outer surface of the guide wire is reduced, and the slidability of the guide wire in the catheter is improved, so that the guide wire can be easily operated.

Specific examples of natural water-soluble polymer substances include starch-based substances such as carboxymethyl starch and dialdehyde starch, cellulose-based substances such as carboxymethyl cellulose and hydroxyethyl cellulose, tannins, lignin-based substances, alginic acid, and gum arabic heparin.
Polysaccharides such as chitin and chitosan, proteins such as gelatin and casein are considered. As the synthetic water-soluble polymer substance, polyvinyl alcohol, polyalkylene oxide-based polyethylene oxide, polyalkylene glycol-based polyethylene glycol,
Acrylic acid-based, polyacrylic acid soda, maleic anhydride-based, methyl vinyl ether maleic anhydride copolymer, methyl vinyl ether sodium maleic anhydride, methyl vinyl ether maleic anhydride ammonium salt, maleic anhydride ethyl ester copolymer, phthalate Acid-based polyhydroxyethyl phthalate, water-soluble polyester polydimethylol propionate, acrylamide-based polyacrylamide hydrolyzate, polyacrylamide quaternized product, polyvinylpyrrolidone, polyethyleneimine, polyethylenesulfonate, water-soluble nylon And so on. Maleic anhydride is preferable, and maleic anhydride ethyl ester copolymer is particularly preferable.

Further, the derivative of the water-soluble polymer substance is not limited to water-soluble, and may be insolubilized one as long as it has the above-mentioned water-soluble polymer substance as a basic constitution. Any material can be used as long as it contains water and exhibits lubricity. For example, in the case of the above water-soluble polymer substance, addition,
Esterification products obtained by substitution, oxidation, reduction reactions, etc.
Salts, amidates, anhydrides, halides, etheterides, hydrolysates, acetals, formalides, alkylol compounds, quaternary compounds, diazo compounds, hydrazide compounds, sulfonate compounds, nitrate compounds, ion complexes, and diazonium compounds. Group, azido group, isocyanate group, acid chloride group, acid anhydride group, imino carbonate group, amino group, carboxyl group, epoxy group, hydroxyl group,
A cross-linked product with a substance having two or more reactive functional groups such as an aldehyde group, a copolymer with a vinyl compound, acrylic acid, methacrylic acid, a diene compound, maleic anhydride, or the like can be considered.

Further, the synthetic resin has a reactive functional group capable of forming an ionic bond or a covalent bond with a lubricating substance as described later, or contains a compound having a reactive functional group, or has a reactive functional group introduced therein. Has been done.

By combining the reactive functional group present or introduced in the synthetic resin with the above-mentioned lubricating substance,
It becomes possible to give lubricity to the surface of synthetic resin,
A persistent lubricious surface can be obtained without dissolving in water. Here, description will be made by using a covalent bond. The lubricating substance is not particularly limited, but the above-mentioned cellulose type, maleic anhydride type, acrylamide type, polyethylene oxide type, water-soluble nylon and the like are preferably used. In particular, hydroxypropyl cellulose, methyl vinyl ether, maleic anhydride copolymer, polyacrylamide, polyethylene glycol, water-soluble nylon (AQ-Nylon P-70 manufactured by Toray Industries, Inc.) and the like are preferable. The average molecular weight of these lubricating substances is not particularly limited, but those having a lubricity of about 3 to 5,000,000 are highly lubricious, have a suitable thickness, and can obtain a lubricating layer having a notably large swelling degree when hydrated. Is.

Further, examples of the lubricating substance fixed to the surface of the synthetic resin by ionic bonding include polyvinylpyrrolidone and the above-mentioned water-soluble polymeric substances such as carboxylates, sulfonates and ammonium salts. Specific examples of the carboxylic acid salt include sodium salts of methyl vinyl ether maleic anhydride, sodium polyacrylate, polyacrylamide hydrolyzate, sodium salt of carboxymethyl cellulose, and sodium alginate. Examples thereof include sodium sulfonate, and ammonium salts include ammonium salts of methyl vinyl ether maleic anhydride and quaternary polyacrylamides.

The reactive functional group present in the synthetic resin is not particularly limited as long as it reacts with the above-mentioned lubricating substance, and bonds or crosslinks to fix it, but diazonium group, azide group, isocyanate. Group, acid chloride group, acid anhydride group, iminocarbonic acid ester group, amino group, carboxyl group, epoxy group, hydroxyl group, aldehyde group and the like, particularly isocyanate group, amino group, aldehyde group,
Epoxy groups are preferred. Therefore, polyurethane, polyamide and the like are suitable as the synthetic resin having a reactive functional group.

Examples of the substance having a reactive functional group include isocyanates such as methylene diisocyanate, ethylene diisocyanate, toluene diisocyanate and diphenylmethane diisocyanate, and adducts or prepolymers of these isocyanates and polyols. Furthermore, for example, ethylenediamine, trimethylenediamine, 1.
2-diaminopropane, tetramethylenediamine, etc. are considered. [I] as a high molecular weight polyamine, poly (alkylene polyamine) synthesized from alkylene dihalide or epichlorohydrin, [II] alkylene imine polymer obtained by ring-opening polymerization of alkylene imine such as ethylene imine and propylene imine,
[III] In addition, there are polyamines such as polyvinylamine and polylysine, polyaldehydes such as glutaraldehyde and terephthalaldehyde, and polyepoxides such as ethylene glycol diglycidyl ether.

[0038]

EXAMPLES Next, examples of the guide wire of the present invention will be described. As the inner core, the total length is 1800 mm, the diameter of the front end is 0.06 mm, the diameter of the rear end is 0.25 mm,
A taper having a diameter of 120 mm tapered from the tip toward the tip was prepared. As a material for the inner core, a TiNi alloy containing 51% Ni atoms was used. And with pure gold, inner diameter 0.07mm, outer diameter 0.3mm, length 2.0m
A pipe-shaped member of m was prepared, inserted into the tip of the inner core, sandwiched with a jig, and crimped and fixed to the inner core to form a high X-ray contrast section. Further, the outer surface of the entire inner core was coated with polyurethane containing 45% by weight of fine tungsten powder (particle size: about 3 to 4 μm) so that the entire outer diameter was substantially uniform, to form a synthetic resin coating. Then, a solution prepared by dissolving maleic anhydride ether ester copolymer in tetrahydrofuran so as to be 5.0% by weight is applied to the surface of the synthetic resin coating formed by the above polyurethane, and maleic anhydride ethyl ester copolymer is added. The coalescence was fixed to form a lubricious surface.

This guide wire has an overall length of about 1
800mm, the overall diameter is 0.36mm, the bending load at the tip of the guide wire is about 4g, and the restoring load is about 2
It was g. When X-ray imaging of the entire guide wire was performed, a high X-ray contrast image was obtained at the tip.

[0040]

Next, the operation of the guide wire of the present invention will be described with reference to the embodiment shown in FIG. The guide wire 1 is introduced into a blood vessel together with the catheter in a state where the distal end portion of the guide wire 1 is projected from the distal end portion of the catheter (not shown), and the distal end portion of the guide wire 1 guides the distal end portion of the catheter to guide the catheter. Is inserted into a predetermined blood vessel site. At this time, the guide wire 1 and the distal end of the catheter are advanced by X-ray imaging while advancing the guide wire and the catheter. After the distal end of the catheter reaches the vicinity of the target site, the guide wire is removed from the catheter. To do.

[0041]

The guide wire of the present invention is provided with an inner core integrally formed with a highly rigid main body portion and a distal end portion having a smaller diameter than the main body portion and having low rigidity, and provided at the distal end of the distal end portion. A high X-ray contrast part, a synthetic resin film encapsulating the inner core provided with the high X-ray contrast part, and a lubricant substance fixed to the surface of the synthetic resin film, In particular, since the high X-ray contrast part is provided at the tip of the inner core, the position of the tip can be surely grasped under X-ray contrast, so that the guide wire and the subsequent catheter introduction work can be performed easily. be able to.

Further, since the lubricating substance is fixed to the synthetic resin coating which is the outer surface of the guide wire, the friction between the inner wall of the catheter and the outer surface of the guide wire is reduced at the time of introducing the catheter, and the guide wire of the guide wire inside the catheter is reduced. Since the slidability is improved, the guide wire can be easily operated.

Further, since the inner core is made of a superelastic alloy and the tip portion has a small diameter, the tip portion is displaced relatively large under a constant stress and is capable of recovering elastic strain characteristics. Can be provided. Therefore, when the distal end advances through the bent portion of the blood vessel, a large bending deformation easily occurs with a relatively small load, so that the responsiveness of the distal end portion is good and the bent portion of the blood vessel is not damaged. By repeating the bending deformation and its restoration in response to the change of the shape, the shape adaptability to the tortuous blood vessel is good, and the blood vessel branch can be bent relatively easily and can be easily introduced into a predetermined blood vessel site. it can. Furthermore, this guide wire has a good torque transmissibility in the main body part in both twisting directions, and the torque applied to the main body part can reliably and easily direct the distal end part toward a predetermined blood vessel site, and thus the complicated blood vessel Good operability for insertion into the site.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of a guide wire of the present invention.

FIG. 2 is an enlarged cross-sectional view taken along the line II of FIG.

FIG. 3 is a cross-sectional view of another embodiment of the guide wire of the present invention.

[Explanation of symbols]

 1 Guide wire 2 Inner core 3 High X-ray contrast material 4 Synthetic resin coating

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] April 14, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

6. An inner core composed of a main body and a distal end portion formed so as to have a diameter gradually decreasing toward the distal end, and a coiled high X-ray contrast portion provided at the distal end of the inner core. A guide wire, characterized in that it has a synthetic resin coating that encloses the inner core provided with the high X-ray contrast section in a close contact state, and that the surface of the synthetic resin coating has antithrombogenicity. ─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] April 14, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

[0013] As the inner core 2, TiNi Alloy 49-5 3 atomic% Ni, the 38.5 to 41.5 wt% Zn Cu-
Zn alloy, 1-10 wt% X Cu-Zn-X alloy (X
= Be, Si, Sn, Al, Ga), 36 to 38 atomic%
A super elastic metal body such as a Ni-Al alloy of Al is preferably used. The above TiNi alloy is particularly preferable.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

As a method for forming such a coil-shaped high X-ray contrast part, a method of directly winding a thin wire on the inner core as described above, or a coil-shaped one formed on the tip of the inner core. A method of attachment is conceivable, and moreover, it is preferable to securely fix them to the tip of the inner core. As a method thereof, it is possible to fix them by crimping a coiled wound or attached coil from the outside. preferable. As another method, a metal for enhancing the adhesiveness with the high X-ray contrast part is plated or vapor-deposited on the tip of the inner core, and the thin wire is wound or coiled on the metal. Alternatively, it may be soldered. The coil body is generally easily deformed, and if the deformation is equal to or less than a predetermined stress value, it is elastic deformation. Therefore, if the high X-ray contrast part has such a coil shape, the flexibility of the tip of the guide wire is not significantly impeded. Further, by having such a high X-ray contrast part, the visibility of the tip of the guide wire under fluoroscopy is improved. Furthermore, materials such as those mentioned above
The coil body formed by
Plastic deformation is caused by the addition. In other words, with your finger
By bending the coil body to pull it,
The tip of the can be deformed. In this way
For transforming the tip of the guide wire into the desired shape
Therefore, it is adapted to the shape of the bifurcation of the blood vessel,
Easy to insert. Then, the coil body described above is formed.
Materials such as gold, platinum, lead, silver, bismuth, and tungsten.
Have high X-ray contrast and the plastic deformability described above.
Maintain the deformed tip shape.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0023

[Correction method] Change

[Correction content]

Further, as shown in FIG. 1, the synthetic resin coating 4 covering the entire inner core 2 has a substantially uniform outer diameter including the tip portion. In particular, the synthetic resin coating 4 has a substantially uniform outer diameter so that steps or the like due to the high X-ray contrast portion provided at the tip of the inner core 2 do not affect the outer surface shape of the guide wire 1. It should be noted that the synthetic resin coating (cover portion) 4
Is provided so as to cover only the high X-ray contrast unit 3
Well, if the high X-ray contrast part 3 is a coil body,
It is provided so as to cover the inner core of the part other than the X-ray contrast part 3.
You may stay.

Claims (6)

[Claims] 1. An inner core integrally formed with a body portion having high rigidity and a tip portion having a diameter smaller than that of the body portion and having low rigidity,
A high X-ray contrast part provided at the tip of the inner core, a synthetic resin film encapsulating the inner core provided with the high X-ray contrast part, and a lubricating substance fixed to the surface of the synthetic resin film. Guide wire characterized by consisting of. 2. The guide wire according to claim 1, wherein the high X-ray contrast part is a metal annular member fixed to the tip of the inner core and having high X-ray contrast. 3. The guide wire according to claim 2, wherein the annular member is a coil or a pipe-shaped member. 4. The high X-ray contrast section is a metal layer having a high X-ray contrast property, which is coated on the tip of the inner core.
Guide wire described in. 5. An inner core composed of a main body and a tip portion formed so as to have a diameter gradually decreasing toward the tip, a high X-ray contrast section provided at the tip of the inner core, and the high X-ray contrast section. A guide wire, characterized in that it has a synthetic resin coating that encloses the inner core provided with an X-ray contrast part in a close contact state, and that the surface of the synthetic resin coating has lubricity when wet. 6. An inner core composed of a main body and a distal end portion formed so as to have a diameter gradually decreasing toward the distal end, and a coiled high X-ray contrast portion provided at the distal end of the inner core. A guide wire, characterized in that it has a synthetic resin coating that encloses the inner core provided with the high X-ray contrast section in a close contact state, and that the surface of the synthetic resin coating has antithrombogenicity.