Guide wire

Abstract

To provide a guide wire which can be provided with a desired intensity of magnetism at a distal end.SOLUTION: A guide wire comprises a core wire, the core wire having a first magnetized area magnetized at its distal end side, the maximum value of the outer diameter of the first magnetized area being larger than the outer diameter of a distal end part in an area closer to a proximal end side than the first magnetized area.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a guide wire.

Background Art

[0002] As a method for confirming the position of a medical device inserted into a living body lumen, a method using a contrast agent and radiography has been conventionally performed. In recent years, however, the development of a technique for confirming the position using magnetism has been underway. For example, Patent Document 1 discloses a technique for detecting the magnetic field intensity and the like of a plurality of magnetic regions provided in a medical device and specifying the position and direction of the medical device. Patent Document 2 discloses a technique for tracking the position of a guide wire around which a magnetic position sensor is wound based on magnetism. Further, as another technique using magnetism, Patent Document 3 discloses a technique for inducing a tip portion by applying a magnetic repulsive force to a guide wire provided with a magnet head at the tip portion.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] In any of the technologies disclosed in Patent Documents 1 to 3, it is premised that a certain degree of strong magnetism is possessed by the magnetic source. Here, consider the case where magnetism is to be given to the tip of the guide wire in order to track the behavior of the tip. In such a case, for example, as disclosed in Patent Document 3, it is conceivable to dispose a permanent magnet at the tip, but there is a risk of a decrease in the flexibility of the tip, and the structure of the tip becoming complicated and enlarged. Therefore, it is conceivable to magnetize the guide wire itself to give it magnetism, but the guide wire often has a smaller diameter at the tip, and there is a possibility that even if such a tip is magnetized, magnetism of a desired strength cannot be given. Note that in the technologies disclosed in Patent Documents 1 to 3, no consideration is given to giving magnetism of a desired strength to the tip of the guide wire.

[0005] The present invention has been made to solve at least a part of the above-described problems, and an object thereof is to provide a guide wire capable of having magnetism of a desired strength at the tip.

Means for Solving the Problems

[0006] The present invention has been made to solve at least a part of the above-described problems and can be realized in the following forms.

[0007] (1) According to one aspect of the present invention, a guide wire is provided. This guide wire is a guide wire including a core wire, and the core wire has a first magnetization region magnetized on the tip side of the core wire, and the maximum value of the outer diameter of the first magnetization region is larger than the outer diameter of the tip portion in the region on the base end side rather than the first magnetization region.

[0008] According to this configuration, the maximum value of the outer diameter of the first magnetization region at the tip side of the core wire is larger than the outer diameter of the tip portion in the region closer to the base end side than the first magnetization region. Therefore, compared with a core wire having a constant outer diameter at the tip side or a tapered core wire whose outer diameter decreases toward the tip side, the volume of the first magnetization region per unit length can be increased, so that a large magnetism can be imparted to the first magnetization region. That is, it becomes possible to impart a desired strength of magnetism to the tip portion of the guide wire. As a result, the magnetic sensor disposed outside the living body can easily detect the tip portion of the guide wire inserted into the living body lumen, so that the detection accuracy of the tip portion of the guide wire by the magnetic sensor can be improved. In addition, since the movement of the tip portion of the guide wire can be easily grasped by the operator due to the improvement of the detection accuracy, the procedure can be carried out accurately and efficiently.

[0009] (2) In the guide wire of the above-described embodiment, the core wire further has a second magnetization region magnetized at a position separated from the first magnetization region on the base end side of the first magnetization region, and the maximum value of the outer diameter of the first magnetization region may be larger than the outer diameter of the tip portion in the region between the first magnetization region and the second magnetization region. According to this configuration, the core wire has a second region magnetized on the base end side of the first magnetization region, and the first magnetization region and the second magnetization region are separated from each other. Therefore, the positions of the first magnetization region and the second magnetization region can be detected separately. Further, based on the positions of the first magnetization region and the second magnetization region detected separately, the degree of curvature of the guide wire in the range from the second magnetization region to the first magnetization region can be grasped.

[0010] (3) In the guide wire of the above-described embodiment, the second magnetization region includes a magnetized coil that covers the outer peripheral surface of the core wire, and the maximum value of the outer diameter of the coil as the second magnetization region may be larger than the outer diameter of the base end portion in the region between the first magnetization region and the second magnetization region, and may also be larger than the outer diameter of the tip portion in the region closer to the base end side than the second magnetization region. According to this configuration, while maintaining the flexibility of the core wire, the volume of the second magnetization region per unit length can be increased. Therefore, since a large magnetic force can be given to the second magnetization region, the detection accuracy of the second magnetization region is improved, and thus the degree of curvature of the guide wire in the range from the second magnetization region to the first magnetization region can be grasped more accurately.

[0011] (4) In the guide wire of the above form, in the core wire, the maximum value of the outer diameter of the core wire in the second magnetization region is larger than the outer diameter of the base end portion in the region between the first magnetization region and the second magnetization region, and is also larger than the outer diameter of the tip portion in the region on the base end side of the second magnetization region, and it may be formed in this way. According to this configuration, the volume of the second magnetization region per unit length can be increased without separately assembling a member to the core wire. Therefore, since a large magnetic force can be given to the second magnetization region, the detection accuracy of the second magnetization region is improved, and thus the degree of curvature of the guide wire in the range from the second magnetization region to the first magnetization region can be grasped more accurately.

[0012] (5) In the guide wire of the above form, the core wire may have a bent portion where the core wire is bent in the region between the first magnetization region and the second magnetization region. According to this configuration, the accuracy of separately detecting the first magnetization region provided on the tip side of the bent portion and the second magnetization region provided on the base end side of the bent portion can be improved. And by using the positions of the separately detected first magnetization region and second magnetization region, the three-dimensional movement of the tip of the guide wire can be accurately grasped. Specifically, when a deformation such as bending occurs in the guide wire, mainly the tip side of the bent portion is deformed. Therefore, by tracking the position of the first magnetization region with reference to the position of the second magnetization region on the base end side of the bent portion, the three-dimensional movement of the tip of the guide wire can be accurately grasped. As a result, the operator can proceed with the procedure accurately and efficiently.

[0013] (6) In the guide wire of the above-described embodiment, a diameter-expanded portion having an outer diameter gradually expanding from the proximal end side toward the distal end side may be formed at the proximal end portion of the first magnetization region. According to this configuration, it is possible to make it difficult to generate a rigidity gap in which the bending rigidity greatly changes at the proximal end portion of the first magnetization region, suppress the proximal end portion of the first magnetization region from bending, and increase the volume of the first magnetization region per unit length.

[0014] (7) In the guide wire of the above-described embodiment, a distal-end diameter-reduced portion having an outer diameter gradually reducing from the proximal end side toward the distal end side may be formed at the distal end portion of the first magnetization region. According to this configuration, since the outer diameter of the distal end portion of the first magnetization region gradually reduces from the proximal end side toward the distal end side, when there is a lesion or the like that clogs the lumen in the biological lumen into which the guide wire is inserted, it is possible to easily insert the guide wire into the lesion or the like.

[0015] (8) According to one embodiment of the present invention, a guide wire is provided. This guide wire is a guide wire including a core wire and a coil covering the core wire, the coil has a magnetized magnetization region, and the wire forming the magnetization region in the coil is thicker than the wire forming the distal end portion in the region on the proximal end side of the magnetization region. According to this configuration, the wire forming the magnetization region is thicker than the wire forming the distal end portion in the region on the proximal end side of the magnetization region. Therefore, since the volume of the magnetization region per unit length can be increased, a large magnetism can be given to the magnetization region.

[0016] Note that the present invention can be realized in various aspects. For example, it can be realized in the form of a core wire used for a guide wire, a medical device including a guide wire, a manufacturing method of a core wire or a guide wire, a system for detecting the position of a guide wire inserted into the body, and the like.

Brief Description of the Drawings

[0017]

Figure 1

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Modes for Carrying Out the Invention

[0018] <The First Embodiment> FIG. 1 is an explanatory diagram showing a schematic configuration of a guide wire 1 according to the first embodiment. The guide wire 1 is a medical device inserted into a biological lumen in each organ of the human body, such as the vascular system, lymphatic gland system, biliary tract system, urinary tract system, airway system, digestive organ system, secretory gland, and reproductive organ. The guide wire 1 may be directly inserted into the above-described biological lumen, or may be inserted into the biological lumen via an endoscope. The guide wire 1 includes a core wire 10, a tip joint portion 24, an outer coil 30, and a proximal end joint portion 52.

[0019] In FIG. 1, an axis passing through the center of the guide wire 1 is represented by an axis O (dashed line). FIG. 1 shows a longitudinal section along the direction of the axis O of the guide wire 1. In the example of FIG. 1, the axis O coincides with the axis passing through the centers of the guide wire 1 and each component member. However, the axis O may be different from the central axes of the guide wire 1 and each component member. FIG. 1 shows XYZ axes that are mutually orthogonal. The X axis corresponds to the longitudinal direction (axis O direction) of the guide wire 1, the Y axis corresponds to the height direction of the guide wire 1, and the Z axis corresponds to the width direction of the guide wire 1. The left side (-X axis direction) of FIG. 1 is called the "tip side" of the guide wire 1 and each component member, and the right side (+X axis direction) of FIG. 1 is called the "proximal end side" of the guide wire 1 and each component member. For the guide wire 1 and each component member, the end located on the tip side is called the "tip", and the tip and its vicinity are called the "tip portion". Also, the end located on the proximal end side is called the "proximal end", and the proximal end and its vicinity are called the "proximal end portion". The tip side is inserted into the body interior, and the proximal end side is operated by an operator such as a doctor. These points are common also in FIGS. 1 and later.

[0020] The core wire 10 is a long member. The core wire 10 has, in order from the proximal end side toward the tip side, a large-diameter portion 11, a reduced-diameter portion 12, a small-diameter portion 13, and a tip large-diameter portion 20.

[0021] The large-diameter portion 11 is formed on the proximal end side of the core wire 10. The large-diameter portion 11 has a substantially cylindrical shape with a substantially constant outer diameter and is a portion with a larger outer diameter compared to the reduced-diameter portion 12 and the small-diameter portion 13. In this specification, "substantially constant" has the same meaning as "generally constant" and means that it is generally constant while allowing for fluctuations due to manufacturing errors and the like. The large-diameter portion 11 is not covered by the outer coil 30 and is used when the operator grips the guide wire 1. The reduced-diameter portion 12 is formed between the large-diameter portion 11 and the small-diameter portion 13 of the core wire 10. The reduced-diameter portion 12 has a tapered shape in which the outer diameter gradually decreases from the proximal end side toward the distal end side. The small-diameter portion 13 is formed between the distal large-diameter portion 20 and the reduced-diameter portion 12 of the core wire 10. The small-diameter portion 13 has a substantially cylindrical shape with a substantially constant outer diameter and is the portion where the outer diameter of the core wire 10 is the smallest. The outer diameter and length of each part (large-diameter portion 11, reduced-diameter portion 12, small-diameter portion 13) of the core wire 10 can be arbitrarily determined.

[0022] The distal large-diameter portion 20 is formed on the distal end side of the core wire 10. The distal large-diameter portion 20 has a substantially cylindrical shape with a substantially constant outer diameter. Also, the distal large-diameter portion 20 is the first magnetization region MR1 magnetized on the distal end side of the core wire 10. Here, the magnetization region is a region magnetized by the application of an external magnetic field. In FIG. 1, a dot-pattern hatching is applied to the distal large-diameter portion 20 and the portion of the outer coil 30 disposed around it, and this hatching indicates the magnetized portion. Also, in the following figures after FIG. 1, it is common that the dot-pattern hatching indicates the magnetized portion. In the present embodiment, the region of the core wire 10 that is not magnetized (small-diameter portion 13, reduced-diameter portion 12, and large-diameter portion 11) on the proximal end side of the first magnetization region MR1 corresponds to the non-magnetization region NR. Here, the non-magnetization region is a region that has not been magnetized by the application of an external magnetic field and may have a slight magnetism due to the influence of shape processing and the like.

[0023] The material forming the distal large-diameter portion 20 can be arbitrarily determined as long as it is a magnetic material that is magnetized by applying an external magnetic field. Examples of such materials include stainless steels in which martensitic transformation occurs (e.g., SUS304, SUS316, SUS302, SUS444, SUS434, SUS630), martensitic stainless steels (e.g., SUS410), and ferritic stainless steels (e.g., SUS430). On the other hand, the material forming the core wire 10 corresponding to the non-magnetized region NR may be the same material as the distal large-diameter portion 20 or may be a non-magnetic material.

[0024] The distal joint portion 24 joins the outer coil 30 and the tip of the core wire 10 (the tip of the distal large-diameter portion 20). The proximal joint portion 52 joins the outer coil 30 and the reduced-diameter portion 12 of the core wire 10. For the joining at the distal joint portion 24 and the proximal joint portion 52, any joining agent can be adopted, such as metal solders like silver solder, gold solder, zinc, Sn-Ag alloy, Au-Sn alloy, or adhesives such as epoxy-based adhesives.

[0025] The outer coil 30 has a substantially cylindrical shape with a substantially constant outer diameter from the proximal end side to the distal end side. The outer coil 30 is arranged to cover a part of the distal large-diameter portion 20, the reduced-diameter portion 13, and the reduced-diameter portion 12 of the core wire 10. In the present embodiment, the outer coil 30 is a single-strand coil formed by winding a single wire 31. Note that the outer coil 30 may be a multi-strand coil formed by winding a plurality of wires in multiple strands, a single-strand twisted wire coil formed by winding a twisted wire obtained by twisting a plurality of wires in a single strand, or a multi-strand twisted wire coil formed by using a plurality of twisted wires obtained by twisting a plurality of wires and winding each twisted wire in multiple strands. The outer diameter and inner diameter of the outer coil 30 can be arbitrarily determined. Also, in the present embodiment, the outer coil 30 is made of a magnetic material that is magnetized by applying an external magnetic field, like the distal large-diameter portion 20, but in other embodiments, it may be a non-magnetic material.

[0026] FIG. 2 is a cross-sectional view of the guide wire 1. FIG. 2(A) shows a cross-section taken along line A-A in FIG. 1. FIG. 2(A) shows a cross-section of the core wire 10 at the position of the tip large-diameter portion 20. The outer diameter r1 is the outer diameter of the tip large-diameter portion 20, which is the first magnetization region MR1. FIG. 2(B) shows a cross-section taken along line B-B in FIG. 1. FIG. 2(B) shows a cross-section of the core wire 10 at the position of the small-diameter portion 13. The outer diameter r2 is the outer diameter of the small-diameter portion 13, which is the non-magnetization region NR. As shown in FIGS. 2(A) and 2(B), the maximum value of the outer diameter r1 of the first magnetization region MR1 is larger than the outer diameter r2 of the tip portion (small-diameter portion 13) in the region (non-magnetization region NR) on the proximal side of the first magnetization region MR1. In the present embodiment, since both the tip large-diameter portion 20 and the small-diameter portion 13 are substantially cylindrical and their cross-sections are circular, the outer diameters r1 and r2 are uniquely determined. However, when the cross-sections of the tip large-diameter portion 20 and the small-diameter portion 13 are elliptical, the length of the longest portion in any cross-section is taken as the outer diameter. Further, when the tip large-diameter portion 20 has a shape different from the substantially cylindrical shape (a shape in which the cross-sectional area is not substantially constant), the longest outer diameter r1 among the outer diameters r1 in each cross-section is taken as the maximum value and compared with the outer diameter r2. Similarly, when the tip portion of the non-magnetization region NR has a shape different from the substantially cylindrical shape (a shape in which the cross-sectional area is not substantially constant), the longest outer diameter r2 among the outer diameters r2 in each cross-section is compared with the maximum value of the outer diameter r1.

[0027] FIG. 3 is a flowchart of a method for manufacturing the guide wire 1. FIGS. 4(A), (B), and (C) are explanatory diagrams showing the manufacturing process of the guide wire 1. The XYZ axes shown in the lower right position in FIG. 4 are shared by each of FIGS. 4(A), (B), and (C). In the manufacture of the guide wire 1, as shown in FIG. 4(A), first, a rod-shaped member 10p1 is prepared (step S10). The rod-shaped member 10p1 is a member that serves as the basis of the core wire 10 (FIG. 1). Next, as shown in FIG. 4(B), by performing a cutting process on the rod-shaped member 10p1, a rod-shaped member 10p2 is formed (step S20). The cutting process is performed using a grinder or the like. The rod-shaped member 10p2 has, in order from the base end side to the tip end side, a large-diameter portion 11, a reduced-diameter portion 12, a small-diameter portion 13, and a cylindrical portion 20p. The cylindrical portion 20p is a member that serves as the basis of the tip large-diameter portion 20 and is the tip large-diameter portion 20 before magnetization. That is, the rod-shaped member 10p2 has the shape of the core wire 10 but is a core wire 10 whose tip portion is not magnetized.

[0028] Next, as shown in FIG. 4(C), the tip of the cylindrical portion 20p is joined to the tip of the outer coil 30 via the tip joint portion 24 (step S30), and a part of the reduced-diameter portion 12 is joined to the base end of the outer coil 30 via the base end joint portion 52 (step S40). Thereafter, the cylindrical portion 20p is magnetized by the application of an external magnetic field from a magnetization device (not shown) to become the tip large-diameter portion 20 (step S50). At this time, the portion of the outer coil 30 disposed around the cylindrical portion 20p is also magnetized (FIG. 1). As the magnetization device, for example, a permanent magnet or an air-core coil that generates a magnetic field by passing an electric current may be provided. After the external magnetic field is applied, the method for manufacturing the guide wire 1 ends. In the manufacturing process described with reference to FIG. 4, the shape of the core wire 10 was integrally formed, but it may be formed separately. In such a case, after manufacturing a rod-shaped member having a large-diameter portion 11, a reduced-diameter portion 12, and a small-diameter portion 13 by cutting, the shape of the core wire 10 is formed by joining a cylindrical portion 20p (a member that serves as the basis of the tip large-diameter portion 20) to the tip of the rod-shaped member. The joining is performed by laser welding or soldering.

[0029] As described above, according to the guide wire 1 of the first embodiment, compared with a core wire having a constant outer diameter on the tip side or a tapered core wire whose outer diameter decreases toward the tip side, the volume per unit length of the tip thickened portion 20 (first magnetization region MR1) formed at the tip of the core wire 10 can be increased. Therefore, a large magnetic field can be applied to the tip thickened portion 20 (first magnetization region MR1). (Here, the unit length refers to the unit length in the longitudinal direction of the core wire 10.) That is, it becomes possible to give the tip of the guide wire 1 a magnetic field of a desired strength. As a result, a magnetic sensor disposed outside the living body can easily detect the tip of the guide wire 1 inserted into the living body lumen, so that the detection accuracy of the tip of the guide wire 1 by the magnetic sensor can be improved. In addition, since the movement of the tip of the guide wire 1 can be easily grasped by the operator due to the improvement of the detection accuracy, the procedure can be carried out accurately and efficiently.

[0030] Further, in the present embodiment, since the tip thickened portion 20 has a substantially cylindrical shape, the volume occupied by the tip thickened portion 20 (first magnetization region MR1) in the space inside the outer coil 30 having a substantially cylindrical shape is made as large as possible. Therefore, the magnetic field applied to the tip thickened portion 20 (first magnetization region MR1) can be increased accordingly. On the other hand, since the outer diameter of the tip of the non-magnetized region NR is smaller than the maximum value of the outer diameter r1 of the tip thickened portion 20, the bending rigidity of the core wire 10 on the base end side from the tip thickened portion 20 can be lowered, so that the flexibility of the guide wire 1 is maintained.

[0031] When the guide wire 1 of the first embodiment is inserted into the living body lumen, the detailed behavior of the tip of the guide wire 1 can be grasped by the magnetic sensor while grasping the behavior of the entire guide wire 1 by the conventional method using a contrast agent and radiography.

[0032] <Second Embodiment> FIG. 5 is an explanatory diagram showing a schematic configuration of the guide wire 1A according to the second embodiment. The guide wire 1A according to the second embodiment is different from the guide wire 1 (FIG. 1) according to the first embodiment in that it includes an inner coil 40, a proximal joint portion 42, and a distal joint portion 44.

[0033] The inner coil 40 has a substantially cylindrical shape with a substantially constant outer diameter from the proximal end side to the distal end side. The inner coil 40 is a magnetized coil that covers the outer peripheral surface of the core wire 10 (thin diameter portion 13). The inner coil 40 is joined to the core wire 10 (thin diameter portion 13) and the outer coil 30 via the proximal joint portion 42 and the distal joint portion 44. Note that the inner coil 40 may not be joined to the outer coil 30. Further, the inner coil 40, like the outer coil 30, is a single-strand coil formed by winding a single wire 41, but may be a multi-strand coil, a single-strand twisted wire coil, or a multi-strand twisted wire coil. Also, the inner coil 40 is made of a magnetic material that is magnetized by applying an external magnetic field, like the tip thick diameter portion 20 and the outer coil 30.

[0034] As shown in FIG. 5, in the second embodiment, in addition to the tip thick diameter portion 20 and the portion of the outer coil 30 disposed around it being magnetized, the inner coil 40, the covered portion of the core wire 10 whose outer peripheral surface is covered by the inner coil 40, and the portion of the outer coil 30 corresponding to the position where the inner coil 40 exists in the X-axis direction are also magnetized. That is, in the second embodiment, the core wire 10 has a second magnetization region MR2 (FIG. 5) magnetized at a position separated from the first magnetization region MR1 on the proximal end side of the first magnetization region MR1. The second magnetization region MR2 includes the covered portion of the core wire 10 covered by the inner coil 40 and the inner coil 40. Also, a first non-magnetized region NR1 is provided between the first magnetization region MR1 and the second magnetization region MR2, and a second non-magnetized region NR2 is provided on the proximal end side of the second magnetization region MR2. The portion of the core wire 10 on the distal end side of the covered portion covered by the inner coil 40 corresponds to the first non-magnetized region NR1, and the portion on the proximal end side of the covered portion corresponds to the second non-magnetized region NR2.

[0035] FIG. 6 is a cross-sectional view of the guide wire 1A. FIG. 6(A) shows a cross-section taken along line A-A of FIG. 5. FIG. 6(B) shows a cross-section taken along line B-B on the base end portion of the first non-magnetized region NR1 of FIG. 5. FIG. 6(C) shows a cross-section taken along line C-C on the tip end portion of the second non-magnetized region NR2 of FIG. 5. In FIG. 6(A), the outer diameter r3 is the outer diameter of the second magnetized region MR2 and also the outer diameter of the inner coil 40. In FIG. 6(B), the outer diameter r4 is the outer diameter of the first non-magnetized region NR1 and also the outer diameter of the reduced-diameter portion 13. In FIG. 6(C), the outer diameter r5 is the outer diameter of the second non-magnetized region NR2 and also the outer diameter of the reduced-diameter portion 13. As shown in FIGS. 6(A), (B), and (C), the maximum value of the outer diameter r3 of the inner coil 40 as the second magnetized region MR2 is larger than the outer diameter r4 of the base end portion of the first non-magnetized region NR1 and also larger than the outer diameter r5 of the tip end portion of the second non-magnetized region NR2. Note that, similar to the first embodiment, when there is a region in the second magnetized region MR2, the first and second non-magnetized regions NR1 and NR2 whose cross-sectional area of the cross-section is not substantially constant, the longest outer diameter among the outer diameters of each cross-section in that region shall be used for comparison with the outer diameters of other regions.

[0036] Also, the tip end portion of the non-magnetized region in the guide wire 1 of the first embodiment (the position of line B-B in FIG. 1 and the vicinity thereof) corresponds to the tip end portion of the first non-magnetized region NR1 in the guide wire 1A of the second embodiment. Therefore, it can be said that the maximum value of the outer diameter r1 (FIG. 2) of the tip end thickened portion 20 is larger than the outer diameter r4 (FIG. 6) of the tip end portion of the first non-magnetized region NR1.

[0037] Next, a method for manufacturing the guide wire 1A will be described. FIGS. 7(A) to 7(D) are explanatory diagrams showing the manufacturing process of the guide wire 1A. The XYZ axes shown at the lower right position in FIG. 7 are also shared by each of FIGS. 7(A) to 7(D). The manufacturing method of the guide wire 1A is similar to the flowchart shown in FIG. 3 and will be described below. First, as shown in FIG. 7(A), after preparing the rod-shaped member 10p1 (corresponding to step S10 in FIG. 3), as shown in FIG. 7(B), the rod-shaped member 10p1 is subjected to cutting to become the rod-shaped member 10p3 (corresponding to step S20 in FIG. 3). The rod-shaped member 10p3 has a large-diameter portion 11, a reduced-diameter portion 12, and a small-diameter portion 13 in order from the base end side to the tip end side. Next, as shown in FIG. 7(C), after the inner coil 40 is disposed at the position of the small-diameter portion 13 from the tip end side of the rod-shaped member 10p3 and joined via the joint portion 42p and the joint portion 44p, the cylindrical portion 20p is joined to the tip end of the rod-shaped member 10p3, thereby forming the rod-shaped member 10p4. The joining at this time is also performed by laser welding or soldering. Next, as shown in FIG. 7(D), the tip end of the cylindrical portion 20p is joined to the tip end of the outer coil 30 via the tip joint portion 24 (corresponding to step S30 in FIG. 3). Next, by pouring a bonding agent from the outside of the outer coil 30, the small-diameter portion 13 and the inner coil 40 are joined to the middle portion of the outer coil 30 via the proximal joint portion 42 and the distal joint portion 44 formed by expanding the joint portion 42p and the joint portion 44p. Next, a part of the reduced-diameter portion 12 is joined to the base end of the outer coil 30 via the base end joint portion 52 (corresponding to step S40 in FIG. 3). Thereafter, the cylindrical portion 20p, the covered portion of the small-diameter portion 13 covered by the inner coil 40, and the inner coil 40 are magnetized by the application of an external magnetic field from a magnetization device (not shown) (corresponding to step S50 in FIG. 3). At this time, the portions of the outer coil 30 disposed around the cylindrical portion 20p and around the inner coil 40 are also magnetized. Incidentally, when the step of joining the small-diameter portion 13 and the inner coil 40 to the middle portion of the outer coil 30 is omitted in the above-described series of steps, it is also possible to manufacture a guide wire in which the inner coil 40 is not joined to the outer coil 30.

[0038] Also with the guide wire 1A of the second embodiment as described above, similar to the first embodiment, it is possible to give the tip of the guide wire 1A a magnetic force of a desired strength. Further, according to the guide wire 1A of the second embodiment, since the first magnetization region MR1 and the second magnetization region MR2 are separated by the first non-magnetization region NR1, the positions of the first magnetization region MR1 and the second magnetization region MR2 can be detected separately. Further, based on the positions of the first magnetization region MR1 and the second magnetization region MR2 detected separately, the degree of curvature of the guide wire 1A in the range from the second magnetization region MR2 to the first magnetization region MR1 can be grasped.

[0039] Also, in the guide wire 1A of the second embodiment, the maximum value of the outer diameter r3 of the inner coil 40 as the second magnetization region MR2 is larger than the outer diameter r4 at the base end portion of the first non-magnetization region NR1 and also larger than the outer diameter r5 at the tip portion of the second non-magnetization region NR2. Therefore, while maintaining the flexibility of the core wire 10, the volume of the second magnetization region MR2 per unit length can be increased. As a result, a large magnetic force can be given to the second magnetization region MR2, so that the detection accuracy of the second magnetization region MR2 is improved, and thus the degree of curvature of the guide wire 1A in the range from the second magnetization region MR2 to the first magnetization region MR1 can be grasped more accurately.

[0040] When the guide wire 1A of the second embodiment is inserted into the living body lumen, while grasping the behavior of the guide wire 1A in the range from the second magnetization region MR2 to the first magnetization region MR1 in real time by a magnetic sensor, it is also grasped by the conventional method using a contrast agent and radiography at regular intervals. Thus, the radiation exposure amount due to radiography can be suppressed more than when grasping the behavior only by the conventional method for grasping the behavior.

[0041] In the guide wire 1A of the second embodiment, when the first magnetization region MR1 has a stronger magnetic field than the second magnetization region MR2, in a procedure where it is important to grasp the behavior of the tip of the guide wire 1A, the procedure can be carried out accurately and efficiently. Also, when the first magnetization region MR1 and the second magnetization region MR2 have the same magnetic field, since the strength of the magnetic field detected by the magnetic sensor from each region is proportional to the distance from each region, it is possible to provide the guide wire 1A in which the positions of each region can be grasped most easily in software. Further, when the second magnetization region MR2 has a stronger magnetic field than the first magnetization region MR1, the position of the second magnetization region MR2 can be easily grasped. For example, if the tip of the guide wire 1A is inserted into one of the blood vessels on the back side from the branch position so that the second magnetization region MR2 is arranged at the branch position where the blood vessel branches, then when another guide wire is inserted into the other blood vessel on the back side from the branch position next, the second magnetization region MR2 can be used as a mark for the branch position. Note that it is also possible to grasp in real time by the magnetic sensor whether the position of the previously inserted guide wire 1A has shifted while operating another guide wire.

[0042] <Third Embodiment> FIG. 8 is an explanatory diagram showing a schematic configuration of the guide wire 1B of the third embodiment. The guide wire 1B of the third embodiment is different from the guide wire 1A (FIG. 5) of the second embodiment in that it includes a core wire 10b having a curved portion CV.

[0043] In the third embodiment, the core wire 10b has a curved portion CV where the core wire 10b is curved in the first non-magnetized region NR1 which is the region between the first magnetization region MR1 and the second magnetization region MR2. The curved portion CV is also the portion where the axis of the guide wire 1B extending in a certain direction from the base end side is curved. Since the core wire 10b has the curved portion CV, the operability of the tip of the guide wire 1B is improved. For example, when the guide wire 1B is inserted into a blood vessel, the blood vessel selectivity is improved.

[0044] Also with the guide wire 1B of the third embodiment as described above, similar to the first embodiment, it is possible to impart a magnetic field of a desired strength to the tip of the guide wire 1B. Further, according to the guide wire 1B of the third embodiment, it is possible to improve the accuracy of separately detecting the first magnetization region MR1 provided on the tip side of the curved portion CV and the second magnetization region MR2 provided on the base end side of the curved portion CV. Then, using the positions of the separately detected first magnetization region MR1 and the second magnetization region MR2, the three-dimensional movement of the tip of the guide wire 1B can be accurately grasped. Specifically, when a deformation such as bending occurs in the guide wire 1B, mainly the tip side of the curved portion CV is deformed. Therefore, by tracking the position of the first magnetization region MR1 with reference to the position of the second magnetization region MR2 on the base end side of the curved portion CV, the three-dimensional movement of the tip of the guide wire 1B can be accurately grasped. As a result, the operator can perform the procedure accurately and efficiently.

[0045] <Fourth Embodiment> FIG. 9 is an explanatory diagram showing a schematic configuration of a guide wire 1C according to the fourth embodiment. The guide wire 1C according to the fourth embodiment is mainly different from the guide wire 1A (FIG. 5) of the second embodiment in that it does not include the inner coil 40 and includes a core wire 10c having an intermediate large-diameter portion 14 and a tip-side small-diameter portion 15.

[0046] The intermediate large-diameter portion 14 is formed at the tip of the small-diameter portion 13. The intermediate large-diameter portion 14 has a substantially cylindrical shape with a substantially constant outer diameter and is a portion with a larger outer diameter compared to the small-diameter portion 13 and the tip-side small-diameter portion 15 formed at the tip of the intermediate large-diameter portion 14. In FIG. 9, the intermediate large-diameter portion 14 and the portion of the outer coil 30 covering the periphery of the intermediate large-diameter portion 14 in the X-axis direction are hatched with a dot pattern, indicating that they are magnetized. That is, in the fourth embodiment, the intermediate large-diameter portion 14 is the second magnetization region MR2 magnetized on the base end side of the first magnetization region MR1. In the fourth embodiment, a tip large-diameter portion 20 is formed on the tip side of the tip-side small-diameter portion 15.

[0047] FIG. 10 is a cross-sectional view of the guide wire 1C. FIG. 10(A) shows a cross-section taken along line A-A in FIG. 9. FIG. 10(B) shows a cross-section taken along line B-B on the base end portion of the first non-magnetized region NR1 in FIG. 9. FIG. 10(C) shows a cross-section taken along line C-C on the tip end portion of the second non-magnetized region NR2 in FIG. 9. In FIG. 10(A), the outer diameter r6 is the outer diameter of the second magnetization region MR2 and is also the outer diameter of the intermediate thick diameter portion 14. In FIG. 10(B), the outer diameter r7 is the outer diameter of the first non-magnetized region NR1 and is also the outer diameter of the tip side thin diameter portion 15. In FIG. 10(C), the outer diameter r8 is the outer diameter of the second non-magnetized region NR2 and is also the outer diameter of the thin diameter portion 13. As shown in FIGS. 10(A)(B)(C), in the core wire 10c, the maximum value of the outer diameter r6 of the core wire 10c (intermediate thick diameter portion 14) in the second magnetization region MR2 is formed to be larger than the outer diameter r7 at the base end portion of the first non-magnetized region NR1 and also larger than the outer diameter r8 at the tip end portion of the second non-magnetized region NR2. Note that, similar to the second embodiment (FIG. 5) and the like, when there is a region among the second magnetization region MR2 and the first and second non-magnetized regions NR1 and 2 whose cross-sectional shape has a non-substantially constant cross-sectional area, the longest outer diameter among the outer diameters of each cross-section within that region shall be used for comparison with the outer diameters of other regions.

[0048] With the guide wire 1C of the fourth embodiment as described above, similar to the first embodiment, it is possible to impart a magnetic field of a desired strength to the tip end portion of the guide wire 1C. Also, without separately assembling another member to the core wire 10c, the volume of the second magnetization region MR2 per unit length can be increased. Therefore, similar to the second embodiment and the like, since a large magnetic field can be imparted to the second magnetization region MR2, the detection accuracy of the second magnetization region MR2 is improved, and thus the degree of curvature of the guide wire 1C in the range from the second magnetization region MR2 to the first magnetization region MR1 can be accurately grasped.

[0049] <Fifth Embodiment> FIG. 11 is an explanatory diagram showing a schematic configuration of a guide wire 1D according to the fifth embodiment. The guide wire 1D according to the fifth embodiment is different mainly in that it includes a core wire 10d having a constricted portion 21 as compared with the guide wire 1C (FIG. 9) according to the fourth embodiment.

[0050] The constricted portion 21 is formed between an intermediate large-diameter portion 14d and a tip large-diameter portion 20d. The constricted portion 21 has a diameter-reducing portion 21l, an intermediate small-diameter portion 21m, and a diameter-expanding portion 21n in order from the proximal end side to the distal end side. The diameter-reducing portion 21l is formed at the proximal end of the constricted portion 21. In other words, the diameter-reducing portion 21l is formed at the tip of the second magnetization region MR2. The diameter-reducing portion 21l is a portion where the outer diameter gradually decreases from the proximal end side to the distal end side. The intermediate small-diameter portion 21m is formed between the diameter-reducing portion 21l and the diameter-expanding portion 21n in the constricted portion 21. The intermediate small-diameter portion 21m is a portion where the outer diameter decreases more toward the center in the X-axis direction. The diameter-expanding portion 21n is formed at the tip of the constricted portion 21. In other words, the diameter-expanding portion 21n is formed at the base of the first magnetization region MR1. The diameter-expanding portion 21n is a portion where the outer diameter gradually increases from the proximal end side to the distal end side.

[0051] Also with the guide wire 1D according to the fifth embodiment as described above, similar to the first embodiment, it is possible to give the tip of the guide wire 1D a magnetic field of a desired strength. Further, in the fifth embodiment, at the base of the first magnetization region MR1, a diameter-expanding portion 21n where the outer diameter gradually increases from the proximal end side to the distal end side is formed. Therefore, it is possible to make it difficult to generate a rigidity gap where the bending rigidity changes greatly at the base of the first magnetization region MR1, suppress the base of the first magnetization region MR1 from bending, and increase the volume of the first magnetization region MR1 per unit length. Further, in the fifth embodiment, since the diameter-reducing portion 21l is formed at the tip of the second magnetization region MR2, it is also possible to suppress the tip of the second magnetization region MR2 from bending.

[0052] <Sixth Embodiment> FIG. 12 is an explanatory diagram showing a schematic configuration of the guide wire 1E according to the sixth embodiment. The guide wire 1E according to the sixth embodiment is mainly different from the guide wire 1D (FIG. 11) according to the fifth embodiment in that it includes a core wire 10e that does not have an intermediate large-diameter portion 14d.

[0053] In the core wire 10e, a tip large-diameter portion 20e is formed at the tip of the enlarged-diameter portion 23 formed at the tip of the small-diameter portion 13. Similar to the enlarged-diameter portion 21n (FIG. 11), the enlarged-diameter portion 23 is formed at the base end portion of the first magnetization region MR1 and has an outer diameter that gradually increases from the base end side toward the tip side. In the sixth embodiment, the non-magnetized portions (the enlarged-diameter portion 23, the small-diameter portion 13, the reduced-diameter portion 12, and the large-diameter portion 11) of the core wire 10e on the base end side of the first magnetization region MR1 correspond to the non-magnetization region NR.

[0054] Also with the guide wire 1E according to the sixth embodiment as described above, similar to the first embodiment, it is possible to provide a magnetic field of a desired strength at the tip of the guide wire 1E. Further, similar to the sixth embodiment, it is possible to make it difficult to generate a rigidity gap in which the bending rigidity changes greatly at the base end portion of the first magnetization region MR1, suppress the base end portion of the first magnetization region MR1 from bending, and increase the volume of the first magnetization region MR1 per unit length.

[0055] <Seventh Embodiment> FIG. 13 is an explanatory diagram showing a schematic configuration of the guide wire 1F according to the seventh embodiment. The guide wire 1F according to the seventh embodiment is mainly different from the guide wire 1E (FIG. 12) according to the seventh embodiment in that it includes a core wire 10f whose shape on the tip side is different from that of the core wire 10e.

[0056] The core wire 10f has, at its tip portion, an expansion portion 25 and a tip diameter-reducing portion 27 in order from the base end side toward the tip end side. The expansion portion 25 is formed at the tip end portion of the small-diameter portion 13. The expansion portion 25 has, in order from the base end side toward the tip end side, an expanded-diameter portion 25l, a middle large-diameter portion 25m, and a diameter-reducing portion 25n. The expanded-diameter portion 25l is formed at the base end portion of the expansion portion 25. The expanded-diameter portion 25l is a portion where the outer diameter gradually expands from the base end side toward the tip end side. The middle large-diameter portion 25m is formed between the expanded-diameter portion 25l and the diameter-reducing portion 25n in the expansion portion 25. The middle large-diameter portion 25m is a portion where the outer diameter expands more toward the position closer to the center in the X-axis direction. The diameter-reducing portion 25n is formed at the tip end portion of the expansion portion 25. The diameter-reducing portion 25n is a portion where the outer diameter gradually decreases from the base end side toward the tip end side.

[0057] The tip diameter-reducing portion 27 is formed at the tip end portion of the expansion portion 25. In other words, the tip diameter-reducing portion 27 is formed at the tip end portion of the first magnetization region MR1. The tip diameter-reducing portion 27 is a portion where the outer diameter gradually decreases from the base end side toward the tip end side. In the seventh embodiment, the expansion portion 25 and the tip diameter-reducing portion 27 are provided with dot pattern hatching, indicating that they are magnetized. The tip joint portion 24f has a substantially pointed shape formed so as to cover the tip diameter-reducing portion 27, and joins the outer coil 30 and the tip end of the core wire 10f (the tip end of the tip diameter-reducing portion 27).

[0058] Also with the guide wire 1F of the seventh embodiment as described above, similar to the first embodiment, it is possible to impart a magnetic field of a desired strength to the tip of the guide wire 1F. Further, the enlarged diameter portion 25l and the reduced diameter portion 25n make it difficult to generate a rigidity gap in which the bending rigidity changes greatly at the tip and the base end portions of the first magnetization region MR1, suppressing the tip and the base end portions of the first magnetization region MR1 from bending, and the intermediate large diameter portion 25m can increase the volume of the first magnetization region MR1 per unit length. Furthermore, in the seventh embodiment, a tip reduced diameter portion 27 in which the outer diameter gradually decreases from the base end side toward the tip end side is formed at the tip end portion of the first magnetization region MR1. Therefore, when there is a lesion or the like that occludes the lumen in the living body lumen into which the guide wire 1F is inserted, it is possible to facilitate the entry of the guide wire 1F into the lesion or the like. In the case of the seventh embodiment, the tip joining portion 24f formed in a substantially pointed shape with the tip reduced diameter portion 27 as a support pierces into a lesion or the like, facilitating the entry of the guide wire 1F into the lesion or the like.

[0059] <Eighth to Tenth Embodiments> Figs. 14(A), (B), and (C) are explanatory views showing the schematic configurations of the guide wires 1Ga, 1Gb, and 1Gc of the eighth to tenth embodiments. The guide wires 1Ga, 1Gb, and 1Gc of the eighth to tenth embodiments are different from the guide wire 1 (Fig. 1) of the first embodiment in that they include a core wire 10 and a core wire 10g having a different shape on the tip side, and in that they each include an outer coil 30ga, 30gb, or 30gc different from the outer coil 30. The configurations of the guide wires 1Ga, 1Gb, and 1Gc are common in that they each include a core wire 10g, and different in that they each include an outer coil 30ga, 30gb, or 30gc.

[0060] First, the guide wire 1Ga of the eighth embodiment will be described with reference to FIG. 14(A). The core wire 10g has a large-diameter portion 11, a reduced-diameter portion 12, and a small-diameter portion 13 in order from the proximal end side to the distal end side, but does not have a distal-end large-diameter portion 20 on the distal end side. The outer coil 30ga is a single-strand coil made of a magnetic material that is magnetized by applying an external magnetic field, similar to the outer coil 30 of the first embodiment. On the other hand, the outer coil 30ga is formed of wire elements 32 and 35 in order from the proximal end side to the distal end side, and the diameter of the wire element 35 is thicker than that of the wire element 32. The outer coil 30ga is a coil in which a single wire element formed by connecting the wire elements 32 and 35 is wound in a single strand. As shown in FIG. 14(A), the outer coil 30ga has a substantially cylindrical shape (a shape with a substantially constant outer diameter in the cross section).

[0061] The outer coil 30ga has a magnetized region MR magnetized on the distal end side. In the guide wire 1Ga, the portion of the core wire 10g disposed inside the magnetized region MR is also magnetized. Further, the outer coil 30ga has a non-magnetized region NR that is not magnetized on the proximal end side of the magnetized region MR. The magnetized region MR corresponds to the position where the wire element 35 is wound in the outer coil 30ga. The non-magnetized region NR corresponds to the position where the wire element 32 is wound in the outer coil 30ga. The wire element 35 forming the magnetized region MR in the outer coil 30ga is thicker than the wire element 32 forming the distal end portion in the non-magnetized region NR, which is a region on the proximal end side of the magnetized region MR. Also, with the guide wire 1Ga of the eighth embodiment as described above, since the volume of the magnetized region MR per unit length can be increased, a large magnetism can be given to the magnetized region MR. Further, since the magnetized region MR corresponds to the distal end portion of the guide wire 1Ga, it is possible to give the distal end portion of the guide wire 1Ga a magnetism of a desired strength.

[0062] Next, the guide wire 1Gb of the ninth embodiment will be described with reference to FIG. 14(B). The outer coil 30gb is formed from wire elements 32, 33, 34 in order from the proximal end side to the distal end side, and the diameter of the wire element 33 is thicker than those of the wire elements 32 and 34. The outer coil 30gb is a coil in which a single wire element formed by connecting the wire elements 32, 33, 34 is wound. The outer coil 30gb has a magnetized region MR magnetized at an intermediate position. Also in the guide wire 1Gb, the portion of the core wire 10g disposed inside the magnetized region MR is magnetized. Further, the outer coil 30gb has a first non-magnetized region NR1 that is not magnetized on the distal end side of the magnetized region MR and a second non-magnetized region NR2 that is not magnetized on the proximal end side of the magnetized region MR.

[0063] The magnetized region MR corresponds to the position where the wire element 33 is wound in the outer coil 30gb. Also, the first non-magnetized region NR1 is at the position where the wire element 34 is wound in the outer coil 30gb, and the second non-magnetized region NR2 corresponds to the position where the wire element 32 is wound in the outer coil 30gb. The wire element 33 forming the magnetized region MR is thicker than the wire element 32 forming the distal end portion in the second non-magnetized region NR2 and thicker than the wire element 34 forming the proximal end portion in the first non-magnetized region NR1. Also with the guide wire 1Gb of the ninth embodiment as described above, since the volume of the magnetized region MR per unit length can be increased, a large magnetism can be imparted to the magnetized region MR.

[0064] Next, the guide wire 1Gc of the tenth embodiment will be described with reference to FIG. 14(C). The outer coil 30gc is formed of wire elements 32, 33, 34, 35 in order from the proximal end side to the distal end side, and the diameters of the wire elements 33, 35 are thicker than those of the wire elements 32, 34. The outer coil 30gc is a coil in which one wire element connected by the wire elements 32, 33, 34, 35 is wound singly. The outer coil 30gc has a first magnetization region MR1 magnetized at the distal end side. The outer coil 30gc also has a second magnetization region MR2 magnetized at a position separated from the first magnetization region MR1 on the proximal end side of the first magnetization region MR1. Also in the guide wire 1Gc, the portion of the core wire 10g disposed inside the first magnetization region MR1 and the second magnetization region MR2 is magnetized. Further, a first non-magnetization region NR1 is provided between the first magnetization region MR1 and the second magnetization region MR2 in the outer coil 30gc, and a second non-magnetization region NR2 is provided on the proximal end side of the second magnetization region MR2.

[0065] The first magnetization region MR1 and the second magnetization region MR2 correspond to the positions where the wire elements 35, 33 are wound in the outer coil 30gc. On the other hand, the first non-magnetization region NR1 and the second non-magnetization region NR2 correspond to the positions where the wire elements 34, 32 are wound in the outer coil 30gc. The wire element 35 forming the first magnetization region MR1 is thicker than the wire element 34 forming the distal end portion in the first non-magnetization region NR1. Also, the wire element 33 forming the second magnetization region MR2 is thicker than the wire element 34 forming the proximal end portion in the first non-magnetization region NR1 and thicker than the wire element 32 forming the distal end portion in the second non-magnetization region NR2. Also with the guide wire 1Gc of the tenth embodiment as described above, since the volumes of the first magnetization region MR1 and the second magnetization region MR2 per unit length can be increased, large magnetism can be given to the first magnetization region MR1 and the second magnetization region MR2.

[0066] In the eighth to tenth embodiments, the outer coils 30ga, 30gb, and 30gc were single-wire coils, but the outer coils 30ga, 30gb, and 30gc may be multi-wire coils, single-wire stranded coils, or multi-wire stranded coils different from single-wire coils. In such a case, by making the diameter of the wire or strand forming the portion corresponding to the position of the magnetization region MR and the position of the first (second) magnetization region MR1 (MR2) thicker than the diameter of the wire or strand forming the other portion, the same effects as those of the eighth to tenth embodiments can be achieved.

[0067] <Modification Example of the Present Embodiment> The present invention is not limited to the above embodiments, and can be implemented in various aspects without departing from the gist thereof. For example, the following modifications are possible.

[0068] [Modification Example 1] In the above first to tenth embodiments, the configurations of the guide wires 1, 1A to 1F, 1Ga to Gc were exemplified. However, the configuration of the guide wire can be variously changed. For example, in the core wire provided in the guide wire, the portion on the base end side from the tip thickened portion may have a constant outer diameter instead of a thin diameter portion, a thick diameter portion, and a reduced diameter portion. Further, the tip thickened portion which is the first magnetization region may be formed on the tip side not including the tip of the core wire 10. Further, the guide wire may have three or more magnetization regions. Further, the shapes of the members constituting the first magnetization region and the second magnetization region may not be substantially cylindrical, but may be a shape that spreads so as to fill the inner space of the coil. Specifically, it may be a shape having a protruding portion that fills the groove portion formed between the wires wound as a coil. Further, for the outer coil and the inner coil, it is sufficient that the position where the external magnetic field is applied is made of a magnetic material, and the position where the external magnetic field is not applied may be made of a non-magnetic material.

[0069] [Modification Example 2] The configurations of the guide wires 1, 1A to 1F, 1Ga to 1Gc of the above-described first to tenth embodiments and the configurations of each of the above-described modification examples 1 may be combined as appropriate. For example, in the guide wires 1, 1A to 1C of the first to fourth embodiments, a diameter-reducing portion or a diameter-expanding portion may be provided at a portion where the outer diameter of the core wire changes (for example, a portion from the tip of the reduced-diameter portion 13 to the tip large-diameter portion 20). Further, in the guide wires 1, 1C to 1F, 1Ga to 1Gc of the first, fourth to tenth embodiments, it may have the curved portion described in the third embodiment. Further, in the guide wires 1C, D of the fourth and fifth embodiments, the inner coil described in the second embodiment or the like may cover the outer peripheral surface of the intermediate large-diameter portions 14, 14d. Further, in the guide wires 1E, F of the sixth and seventh embodiments, at least one of the inner coil described in the second embodiment or the like and the intermediate large-diameter portion described in the fourth embodiment or the like may be provided. Further, in the guide wires 1Ga to 1Gc of the eighth to tenth embodiments, instead of the core wire 10g, the core wires 10, 10c to 10f of the first, fourth to seventh embodiments may be provided, or the core wire 10 covered with the outer peripheral surface of the inner coil 40 of the second embodiment may be provided.

[0070] As described above, the present aspect has been described based on the embodiments and modification examples. However, the embodiments of the above-described aspects are for facilitating the understanding of the present aspect and do not limit the present aspect. The present aspect can be changed and improved without departing from the spirit and scope of the claims, and equivalents thereof are included in the present aspect. Further, if its technical features are not described as essential in this specification, they can be deleted as appropriate.

Description of Reference Numerals

[0071] 1, 1A to F, 1Ga to 1Gc... Guide wire 10, 10b to g... Core wire 10p1 to 4... Rod-shaped member 11... Large-diameter portion 12... Diameter-reducing portion 13... Reduced-diameter portion 14, 14d... Intermediate large-diameter portion 15... Tip-side reduced-diameter portion 20, 20d, 20e... Tip large-diameter portion 20p…Cylindrical part 21…Constricted part 21l…Diameter-reduced part 21m…Intermediate diameter-reduced part 21n…Diameter-expanded part 23…Diameter-expanded part 24, 24f…Tip joint part 25…Expansion part 25l…Diameter-expanded part 25m…Intermediate large-diameter part 25n…Diameter-reduced part 27…Tip diameter-reduced part 30, 30ga~gc…Outer coil 31, 32, 33, 34, 35…Wire element 40…Inner coil 41…Wire element 42…Proximal joint part 44…Distal joint part 42p…Joint part 44p…Joint part 52…Base-end joint part CV…Bending part MR1…First magnetization region MR2…Second magnetization region NR1…First non-magnetization region NR2…Second non-magnetization region O…Axis r1~8…Outer diameter

Claims

1. A guide wire comprising a core wire, wherein the core wire has a first magnetized region magnetized at the tip side of the core wire, the maximum value of the outer diameter of the first magnetized region is larger than the outer shape of the tip portion in the region on the base end side of the first magnetized region, the core wire further has a second magnetized region magnetized at a position separated from the first magnetized region on the base end side of the first magnetized region, the maximum value of the outer diameter of the first magnetized region is larger than the outer diameter of the tip portion in the region between the first magnetized region and the second magnetized region, the second magnetized region includes a magnetized coil covering the outer peripheral surface of the core wire, the maximum value of the outer diameter of the coil as the second magnetized region is larger than the outer diameter of the base end portion in the region between the first magnetized region and the second magnetized region, and is larger than the outer diameter of the tip portion in the region on the base end side of the second magnetized region. A guide wire.

2. A guide wire comprising a core wire, wherein the core wire has a first magnetized region magnetized at the tip side of the core wire, the maximum value of the outer diameter of the first magnetized region is larger than the outer shape of the tip portion in the region on the base end side of the first magnetized region, a diameter-expanded portion having an outer diameter gradually expanding from the base end side toward the tip side is formed at the base end portion of the first magnetized region. A guide wire.

3. The guide wire according to claim 2, wherein the core wire further has a second magnetized region magnetized at a position separated from the first magnetized region on the base end side of the first magnetized region, the maximum value of the outer diameter of the first magnetized region is larger than the outer diameter of the tip portion in the region between the first magnetized region and the second magnetized region. A guide wire.

4. The guide wire according to claim 3, wherein in the core wire, the maximum value of the outer diameter of the core wire in the second magnetized region is larger than the outer diameter of the base end portion in the region between the first magnetized region and the second magnetized region, and is formed to be larger than the outer diameter of the tip portion in the region on the base end side of the second magnetized region. A guide wire.

5. The guide wire according to claim 1 or claim 3 or claim 4, wherein the core wire has a bent portion where the core wire is bent in the region between the first magnetized region and the second magnetized region. A guide wire. **Claim 6**: The guide wire according to claim 1 or claim 5, wherein a diameter-expanded portion with an outer diameter gradually expanding from the proximal end side toward the distal end side is formed at the proximal end portion of the first magnetization region. **Claim 7** The guide wire according to any one of claims 1 to 6, wherein a distal-end diameter-reduced portion with an outer diameter gradually reducing from the proximal end side toward the distal end side is formed at the distal end portion of the first magnetization region. **Claim 8** A guide wire comprising a core wire and a coil covering the core wire, wherein the coil has a magnetized magnetization region, and strands forming the magnetization region of the coil are thicker than strands forming the distal end portion in a region on the proximal end side of the magnetization region.

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