Guidewire

Abstract

The guide wire comprises: a core shaft having an elongated shape; a first coil body arranged so as to surround the front end of the core shaft; a second coil body arranged radially outwardly of the first coil body; and a front end tip fixing the front end of the core shaft and the front end of the first coil body. In the length direction of the core shaft, the front end of the second coil body is located between the front end and the base end of the first coil body, the base end of the second coil body is located closer to the base end side than the base end of the first coil body, and the bending stiffness of the first coil body is smaller than the bending stiffness of the second coil body.

Description

Technical Field

[0001] The invention relates to a guide wire. Background Art

[0002] A guide wire used when inserting a medical device such as a catheter into a blood vessel or a digestive organ is known. For example, Patent Document 1 discloses a guide wire in which a coil (hereinafter also referred to as a "coil body") is installed at the front end of a long core wire (hereinafter also referred to as a "core shaft"), and the core wire and the coil are fixed by solder. In the guide wire of Patent Document 1, a close-fitting winding portion in which adjacent wires are closely fitted to each other and a spacing pitch portion in which adjacent wires are separated from each other are provided in the coil to suppress the flow of solder during brazing and maintain the flexibility of the front end.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2011-143077 Summary of the invention

[0006] Problems to be solved by the invention

[0007] Here, the guide wire advances in a curved blood vessel while passing through a narrow or occluded lesion. Therefore, the front end side of the guide wire is subjected to the resistance of the lesion or the inner wall of the blood vessel, and sometimes is bent into a U shape. Regarding this point, in the guide wire described in patent document 1, there is the following problem: under the state that the front end side has produced a bend, if the guide wire is also advanced, there is the possibility that the bend of the front end side of the guide wire expands (develops) toward the base end side. It should be noted that such a problem is not limited to the vascular system, and is also common to all guide wires inserted into the biological lumen such as the lymphatic system, the biliary system, the urinary system, the respiratory system, the digestive organ system, the secretory glands and the reproductive organs.

[0008] The present invention has been made to solve at least a part of the above-mentioned problems, and an object of the present invention is to provide a guide wire that improves safety by preventing a bend generated at the distal end side of the guide wire from expanding (developing) toward the proximal end side.

[0009] Means of solving problems

[0010] The present invention has been made to solve at least a part of the above-mentioned problems, and can be implemented as the following aspects.

[0011] (1) According to one embodiment of the present invention, a guide wire is provided. The guide wire comprises: a core shaft having an elongated shape; a first coil body, the first coil body being arranged so as to surround the front end of the core shaft; a second coil body, the second coil body being arranged radially outwardly of the first coil body; and a front end tip, the front end tip fixing the front end of the core shaft and the front end of the first coil body, wherein in the length direction of the core shaft, the front end of the second coil body is located between the front end and the base end of the first coil body, the base end of the second coil body is located closer to the base end side than the base end of the first coil body, and the bending stiffness of the first coil body is smaller than the bending stiffness of the second coil body.

[0012] According to this structure, in the length direction of the core shaft, the front end of the second coil body is located between the front end and the base end of the first coil body, and the base end of the second coil body is located at a position closer to the base end side than the base end of the first coil body. Therefore, the guide wire is configured to have a region (hereinafter referred to as "first region") where the core shaft is surrounded by the first coil body and a region (hereinafter referred to as "second region") where the core shaft is surrounded by the first coil body and the second coil body from the front end side toward the base end side. Here, according to this structure, since the bending rigidity of the first coil body is less than the bending rigidity of the second coil body, the bending rigidity of the first region on the front end side is less than the bending rigidity of the second region. As a result, when the front end portion of the guide wire is subjected to the resistance of the lesion or the inner wall of the blood vessel, the bend generated by the guide wire can be easily generated in the first region or the boundary portion between the first region and the second region. In addition, the bend generated by the front end portion of the guide wire can be suppressed from expanding (developing) to the second region located on the base end side. Therefore, according to this structure, the safety of the guide wire can be improved.

[0013] (2) The guide wire of the above aspect may further include a first fixing portion that fixes a distal end portion of the second coil body and a portion of the first coil body.

[0014] According to this structure, since the guide wire has a first fixed portion that fixes the front end of the second coil body and a part of the first coil body, the torque transmission of the guide wire (the performance of transmitting the operation of the guide wire at the proximal part to the front end side) can be improved. In addition, by having the first fixed portion, the bend generated by the guide wire can be easily generated at a position closer to the front end side than the first fixed portion. As a result, the bend generated by the front end of the guide wire can be further suppressed from expanding to the second area located at the base end side.

[0015] (3) In the guide wire of the above aspect, the first fixing portion may further fix the distal end portion of the second coil body and a portion of the core shaft.

[0016] According to this structure, the first fixing part also fixes the front end of the second coil body and a part of the core shaft. Therefore, the bending generated by the guide wire can be easily generated at a position closer to the front end side than the first fixing part, and the bending generated by the front end of the guide wire can be further suppressed from expanding to the second area located at the base end side.

[0017] (4) In the guide wire of the above-mentioned method, the core shaft may also have: a tapered portion, the outer diameter of which is tapered from the base end toward the front end; and a flat portion, which is arranged closer to the front end side than the tapered portion and has a flat plate-like appearance, wherein the base end of the flat portion and the front end of the second coil body are positioned in the same position in the length direction of the core shaft.

[0018] According to this structure, since the mandrel includes a flat plate portion with a flat-shaped outer shape at a position closer to the front end side than the tapered portion, the shaping performance of the guide wire can be improved (the performance of the ease of the shape when the front end of the guide wire is given a shape such as a bend to guide the front end of the guide wire to the target blood vessel). In addition, since the mandrel has a tapered portion whose outer diameter is reduced from the base end toward the front end, the front end side of the guide wire can be made soft. Moreover, since the base end of the flat plate portion is consistent with the front end of the second coil body in the length direction of the mandrel, the rigidity difference between the first region and the second region can be made larger. As a result, the bending produced by the guide wire can be made easier to produce in the first region or the boundary portion of the first region and the second region, and the bending produced by the front end of the guide wire can be further suppressed to expand to the second region located at the base end side. Therefore, according to this structure, the safety of the guide wire can be further improved, and the use of the guide wire can be made more convenient.

[0019] (5) In the guide wire of the above-mentioned method, it can also be that it further comprises: a tubular body, wherein the tubular body is arranged radially more outward than the second coil body, wherein the base end of the tubular body is located closer to the base end side than the base end of the second coil body, and the front end tip also fixes the front end of the tubular body.

[0020] According to this configuration, since the proximal end of the tubular body is located more proximal to the proximal end of the second coil body, a region (hereinafter also referred to as a "third region") where the core shaft is surrounded by the tubular body can be formed more proximal to the second region.

[0021] (6) The guide wire of the above aspect may further include a second fixing portion that fixes a portion of the core shaft, a portion of the first coil body, a portion of the second coil body, and a portion of the tubular body.

[0022] According to this structure, since the guide wire has a second fixing portion that fixes a part of the core shaft, a part of the first coil body, a part of the second coil body, and a part of the tubular body, the torque transmission of the guide wire can be improved. In addition, since the first coil body, the second coil body, and the tubular body are fixed to the core shaft by the second fixing portion, the positions of the first coil body, the second coil body, and the tubular body can be suppressed from moving in the length direction (in other words, the first coil body, the second coil body, and the tubular body can be suppressed from shifting relative to each other).

[0023] (7) The guide wire of the above aspect may further include a covering layer covering an outer surface of the distal end tip, an outer surface of the tubular body, and an outer surface of the core shaft located closer to the proximal end than the tubular body.

[0024] According to this configuration, the guide wire includes the covering layer covering the outer surface of the distal tip, the outer surface of the tubular body, and the outer surface of the core shaft located closer to the proximal end than the tubular body, thereby improving the slidability of the guide wire in the blood vessel.

[0025] It should be noted that the present invention can be implemented in various forms, for example, it can be implemented in the form of a guide wire, a set of a coil body and a tubular body mounted on the guide wire, and a method for manufacturing the same. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is an explanatory diagram illustrating the structure of the guide wire according to the first embodiment.

[0027] Figure 2 It is the part of the front end of the guide wire ( Figure 1 : Enlarged view of the image within the dotted box).

[0028] Figure 3 It's an example Figure 2 An illustration of the cross-sectional structure at line AA.

[0029] Figure 4 : is a perspective view which illustrates the structure of the first coil body.

[0030] Figure 5 This is an explanatory diagram illustrating a method for measuring bending rigidity.

[0031] Figure 6 It is an explanatory diagram illustrating the structure of the guide wire according to the second embodiment.

[0032] Figure 7 It is an explanatory diagram illustrating the structure of a guide wire according to a third embodiment.

[0033] Figure 8 It is an explanatory diagram illustrating the structure of a guide wire according to a fourth embodiment.

[0034] Fig. 9 It is an explanatory diagram illustrating the structure of a guide wire according to a fifth embodiment.

[0035] Fig.10 It is an explanatory diagram illustrating the structure of a guide wire according to the sixth embodiment.

[0036] Fig.11 It is an explanatory diagram illustrating the structure of a guide wire according to the seventh embodiment.

[0037] Fig.12 It is an explanatory diagram illustrating the structure of a guide wire according to the eighth embodiment.

[0038] Fig.13 It is an explanatory diagram illustrating the structure of a guide wire according to a ninth embodiment.

[0039] Fig.14 It is an explanatory diagram illustrating the structure of a guide wire according to a tenth embodiment.

[0040] Fig.15 It is an explanatory diagram illustrating the structure of a guide wire according to an eleventh embodiment. DETAILED DESCRIPTION

[0041] <First embodiment>

[0042] Figure 1 1 is an explanatory diagram illustrating the structure of the guide wire 1 of the first embodiment. The guide wire 1 is a medical device used when inserting a medical device such as a catheter into a blood vessel, etc. The guide wire 1 includes a first coil body 10, a second coil body 20, a third coil body 30, a core shaft 40, a first fixing portion 51, a third fixing portion 53, a fourth fixing portion 54, a front end tip 61, and a base end fixing portion 62. The guide wire 1 has a structure described later, and when the front end of the guide wire 1 is subjected to resistance from a lesion or the inner wall of a blood vessel located in a blood vessel, the bend generated by the guide wire 1 is suppressed from expanding (developing) toward the base end side, thereby improving safety. It should be noted that in the following example, although the blood vessel is used as an example, the guide wire 1 is not limited to being inserted into the vascular system for use, and can also be inserted into the lumen of a biological body such as the lymphatic system, the biliary system, the urinary system, the respiratory system, the digestive system, the secretory glands, and the reproductive organs for use.

[0043] exist Figure 1 In FIG. 1 , an axis O (single-dot chain line) is used to represent an axis passing through the center of the guide wire 1. Figure 1 In the example of FIG. 1 , the axis O coincides with the axes passing through the centers of the first to third coil bodies 10 , 20 , 30 and the core shaft 40 . However, the axis O may be different from the center axes of the above-mentioned structural members. Figure 1In the figure, mutually orthogonal XYZ axes are shown. The X axis corresponds to the length 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. Figure 1 The left side (-X axis direction) is called the "front end side" of the guide wire 1 and each structural member, and Figure 1 The right side (+X axis direction) is called the "base end side" of the guide wire 1 and each structural member. In addition, of the two ends in the length direction (X axis direction) of the guide wire 1 and each structural member, the end located on the front end side is called the "front end", and the other end located on the base end side is called the "base end". In addition, the front end and its vicinity are called the "front end portion", and the base end and its vicinity are called the "base end portion". The front end side is inserted into the body, and the base end side is operated by a surgeon such as a doctor. These points are in Figure 1 This is also common in the following figures.

[0044] Figure 2 It is a part of the front end side of the guide wire 1 ( Figure 1 : Enlarged view of the image within the dotted box). Figure 3 It's an example Figure 2 An illustration of the cross-sectional structure at line AA of FIG. Figure 1 As shown, the mandrel 40 has an elongated outer shape extending along the axis O. The mandrel 40 has a flat plate portion 41, a tapered portion 42, and a large diameter portion 43 from the front end toward the base end.

[0045] The flat plate portion 41 is disposed at the most distal end side of the core shaft 40. The flat plate portion 41 is a strip-shaped portion ( Figure 1 , Figure 2 ),exist Figure 3 In the cross section shown in FIG. 4 , the flat plate portion 41 is a portion having a flat plate-like shape whose length in the Y-axis direction is shorter than its length in the Z-axis direction. Figure 2 As shown in FIG. 1 , the front end of the flat plate portion 41 is fixed to the first coil body 10 and the third coil body 30 via the front end tip 61. The tapered portion 42 is connected to the base end of the flat plate portion 41. Figure 2 As shown, the position B of the base end of the flat plate portion 41 in the direction of the axis O (in other words, in the length direction of the core shaft 40) is consistent with the position B of the front end of the second coil body 20. It should be noted that in this embodiment, "consistent" means roughly consistent, allowing differences caused by manufacturing errors, etc.

[0046] The flat plate portion 41 is a member used to facilitate the shaping of the front end portion of the guide wire 1 when the operator gives the guide wire 1 a bend or other shape, and is also called a "ribbon". Figure 3The length in the Y-axis direction and the Z-axis direction), the length in the axis O direction, and the cross-sectional shape can be determined arbitrarily. It should be noted that the flat plate portion 41 and the tapered portion 42 and the thick-diameter portion 43 may not be coaxial. In this case, a side surface of the base end side of the flat plate portion 41 may be joined to a side surface of the front end side of the tapered portion 42. In addition, the flat plate portion 41 may be omitted.

[0047] like Figure 1 As shown in FIG. 1 , the tapered portion 42 is disposed between the flat portion 41 and the thick-diameter portion 43. The tapered portion 42 is a substantially truncated cone-shaped portion whose outer diameter is reduced from the base end toward the front end. Figure 2 As shown, the flat plate portion 41 is connected to the front end of the tapered portion 42, and the thick diameter portion 43 is connected to the base end of the tapered portion 42. It should be noted that the outer diameter, the length in the axis O direction, and the cross-sectional shape of the tapered portion 42 can be arbitrarily determined.

[0048] The large diameter portion 43 is disposed at the position closest to the base end of the core shaft 40. The large diameter portion 43 is a substantially cylindrical portion having a substantially constant outer diameter from the base end toward the front end. The outer diameter of the large diameter portion 43 is the same as the largest diameter portion of the tapered portion 42. It should be noted that in this embodiment, "same" means substantially the same, which means that differences due to manufacturing errors, etc. are allowed. Figure 2 As shown, the tapered portion 42 is connected to the front end of the large diameter portion 43. The base end of the large diameter portion 43 is held by the operator for operation. It should be noted that the outer diameter, length in the axis O direction, and cross-sectional shape of the large diameter portion 43 can be arbitrarily determined.

[0049] The core shaft 40 is formed of a superelastic alloy (also known as a "hysteresis elastic alloy (pseudo-elastic alloy)"). As a superelastic alloy, for example, NiTi alloy, and alloys of NiTi and other metals can be exemplified. It should be noted that the flat plate portion 41 in the core shaft 40 can also be formed of a material that is more easily plastically deformed than a superelastic alloy. As a material that is more easily plastically deformed than a superelastic alloy, for example, a stainless steel alloy (SUS304, SUS316, etc.) can be exemplified. In addition, a proximal side core shaft can also be provided at a position closer to the base end side than the thick diameter portion 43. The proximal side core shaft can, for example, be formed of a material that is more easily plastically deformed than a superelastic alloy.

[0050] like Figure 2As shown, the first coil body 10 is configured in a manner to surround the front end portion of the core shaft 40. Specifically, the first coil body 10 is configured in a manner to surround a portion of the front end side of the flat portion 41 and the tapered portion 42. The front end of the first coil body 10 is fixed to the core shaft 40 and the third coil body 30 through the front end tip 61. The base end of the first coil body 10 is fixed to the core shaft 40 through the third fixing portion 53. It should be noted that the average coil diameter of the first coil body 10 (the average diameter of the outer diameter and the inner diameter of the first coil body 10) and the length of the first coil body 10 can be determined arbitrarily.

[0051] Figure 4 2 is a perspective view illustrating the structure of the first coil body 10. Figure 4 As shown, the first coil body 10 of the present embodiment is a multi-strand coil formed by winding eight wires 11 into multiple strands, and has a generally cylindrical shape with a constant outer diameter. The first coil body 10 can be formed, for example, by tightly twisting the eight wires 11 on a core bar in a manner of contacting each other, and then using a known heat treatment method to remove residual stress and remove the core bar. The first coil body 10 formed in this way is as shown in FIG. Figure 4 Shown is a multi-strand coil with an inner cavity 10h (dashed line). The material of the wire 11 can be the same as that of the wire 21, or different from that of the wire 21. It should be noted that the first coil body 10 can be formed in any manner. For example, the number of wires 11 constituting the first coil body 10 is not limited to eight and can be determined arbitrarily. The first coil body 10 is not limited to a multi-strand coil, and can also be a single-strand coil formed by winding a wire into a single strand, or a single-strand twisted wire coil formed by winding a stranded wire formed by twisting a plurality of wires into a single strand, or a multi-strand twisted wire coil formed by using a stranded wire formed by twisting a plurality of wires into a plurality of strands and winding each stranded wire into a plurality of strands.

[0052] like Figure 2 As shown, the second coil body 20 is arranged at a radially outer side than the first coil body 10, and surrounds a portion of the core shaft 40 (in the example shown in the figure, a portion of the front end side of the tapered portion 42) and a portion of the base end side of the first coil body 10. In the direction of the axis O (in other words, in the length direction of the core shaft 40), the front end of the second coil body 20 is located between the front end and the base end of the first coil body 10. The front end of the second coil body 20 is fixed to the first coil body 10 by the first fixing portion 51. In addition, in the direction of the axis O, the base end of the second coil body 20 is located at a position closer to the base end side than the base end of the first coil body 10. The base end of the second coil body 20 is fixed to the core shaft 40 by the fourth fixing portion 54.

[0053] The second coil body 20 and Figure 4The first coil body 10 described is the same as that of a multi-strand coil formed by winding a plurality of (e.g., eight) wires 21 into multiple strands, but the second coil body 20 is not limited to a multi-strand coil, and can also be a single-strand coil, a single-strand twisted wire coil, or a multi-strand twisted wire coil. It should be noted that the average coil diameter of the second coil body 20 (the average diameter of the outer diameter and the inner diameter of the second coil body 20) and the length of the second coil body 20 can be determined arbitrarily.

[0054] The third coil body 30 is arranged at a radially outer side than the second coil body 20, and surrounds a portion of the core shaft 40 (in the illustrated example, a portion of the front end side of the flat portion 41 and the tapered portion 42), the first coil body 10, and the second coil body 20. In the direction of the axis O, the front end of the third coil body 30 is located at the same position as the front end of the first coil body 10. The front end of the third coil body 30 is fixed to the core shaft 40 and the first coil body 10 by the front end tip 61. In addition, in the direction of the axis O, the base end of the third coil body 30 is located at a position closer to the base end side than the base end of the second coil body 20. The base end of the third coil body 30 is fixed to the core shaft 40 by the base end side fixing portion 62.

[0055] The third coil body 30 is a single-strand coil formed by winding a wire into a single strand. However, the third coil body 30 is not limited to a single-strand coil, and can also be a multi-strand coil, a single-strand twisted wire coil, or a multi-strand twisted wire coil. It should be noted that the average coil diameter of the third coil body 30 (the average diameter of the outer diameter and the inner diameter of the third coil body 30) and the length of the third coil body 30 can be determined arbitrarily. It should be noted that the third coil body 30 is equivalent to a "tubular body".

[0056] The wire 11 constituting the first coil body 10, the wire 21 constituting the second coil body 20, and the wire 31 constituting the third coil body 30 can be formed of any material. The wire 11, the wire 21, and the wire 31 can be formed of, for example, superelastic alloys such as stainless steel alloys (SUS304, SUS316, etc.), NiTi alloys, radiolucent alloys such as piano wire, nickel-chromium alloys, and cobalt alloys, and radiopaque alloys such as gold, platinum, tungsten, and alloys containing these elements (such as platinum-nickel alloys). The wire 11, the wire 21, and the wire 31 can be formed of the same material or different materials. In the present embodiment, the size relationship between the outer diameter Φ11 of the wire 11, the outer diameter Φ21 of the wire 21, and the outer diameter Φ31 of the wire 31 is Φ11<Φ21<Φ31. However, their size relationship can be determined arbitrarily, for example, it can also be Φ11=Φ21<Φ31, and it can also be Φ11=Φ21=Φ31.

[0057] It should be noted that, in the present embodiment, the outer peripheral surface of the first coil body 10 contacts the inner peripheral surface of the second coil body 20, and the outer peripheral surface of the second coil body 20 contacts the inner peripheral surface of the third coil body 30. However, the outer peripheral surface of the first coil body 10 and the inner peripheral surface of the second coil body 20 may also be separated, and the outer peripheral surface of the second coil body 20 and the inner peripheral surface of the third coil body 30 may also be separated.

[0058] The front end tip 61 is arranged at the front end of the third coil body 30, and holds the front end of the third coil body 30, the front end of the core shaft 40 and the front end of the first coil body 10 as a whole. The base end side fixing portion 62 is arranged at the base end of the third coil body 30, and holds the base end of the third coil body 30 and a part of the core shaft 40 (specifically, a part of the tapered portion 42) as a whole. The first fixing portion 51 is arranged at the front end of the second coil body 20, and holds the front end of the second coil body 20 and a part of the first coil body 10 as a whole. The fourth fixing portion 54 is arranged at the base end of the second coil body 20, and holds the base end of the second coil body 20 and a part of the core shaft 40 (specifically, a part of the tapered portion 42) as a whole. The third fixing portion 53 is arranged at the base end of the first coil body 10, and holds the base end of the first coil body 10 and a part of the core shaft 40 (specifically, a part of the tapered portion 42) as a whole.

[0059] The front end tip 61, the base end fixing portion 62, the first fixing portion 51, the third fixing portion 53 and the fourth fixing portion 54 can be formed by any bonding agent, such as metal solder such as silver solder, gold solder, zinc, Sn-Ag alloy, Au-Sn alloy, or bonding agent such as epoxy resin adhesive. The front end tip 61, the base end fixing portion 62, the first fixing portion 51, the third fixing portion 53 and the fourth fixing portion 54 can be formed by using the same bonding agent or different bonding agents. It should be noted that the front end tip 61, the base end fixing portion 62, the first fixing portion 51, the third fixing portion 53 and the fourth fixing portion 54 can also be formed by laser welding.

[0060] Figure 5 1 is an explanatory diagram illustrating a method for measuring bending stiffness. In the above-mentioned guide wire 1, the bending stiffness of the first coil body 10 is smaller than the bending stiffness of the second coil body 20. In this embodiment, the bending stiffness is measured by Figure 5 The cantilever beam test described is carried out. Specifically, Figure 5 As shown in (A), the measuring object 5 is supported by the gripping member 4. The load sensor 3 of the measuring device 2 is arranged to contact an arbitrary position of the measuring object 5 protruding from the gripping member 4. At this time, a predetermined interval a is set between the contact point P between the measuring object 5 and the load sensor 3 and the end face of the gripping member 4 (the end face facing the measuring device 2). In this state, as shown in FIG. Figure 5 As shown in (B), the contact point P is set as the force point, and the holding member 4 is lowered by a specified amount. Moreover, the measured value of the load sensor 3 when the holding member 4 reaches the specified displacement y is set as the bending stiffness of the measured object 5. The bending stiffness of the first coil body 10 measured in this way is smaller than the bending stiffness of the second coil body 20.

[0061] like Figure 2 As shown, the guide wire 1 of the present embodiment has a first region R1, a second region R2, and a third region R3 from the front end side toward the base end side. The first region R1 is a region where the core shaft 40 is surrounded by the first coil body 10. In the illustrated example, the front end of the first region R1 in the direction of the axis O coincides with the position of the base end of the front end tip 61, and the base end of the first region R1 coincides with the position of the front end of the second coil body 20. The second region R2 is a region where the core shaft 40 is surrounded by the first coil body 10 and the second coil body 20. In the illustrated example, the front end of the second region R2 in the direction of the axis O coincides with the position of the front end of the second coil body 20, and the base end of the second region R2 coincides with the position of the base end of the second coil body 20. The third region R3 is a region where the core shaft 40 is surrounded by the third coil body 30. In the illustrated example, the front end of the third region R3 in the direction of the axis O coincides with the position of the base end of the second coil body 20, and the base end of the third region R3 coincides with the position of the front end of the base end side fixing portion 62.

[0062] like Figure 5 As described, the bending stiffness of the first coil body 10 is smaller than the bending stiffness of the second coil body 20. Therefore, the bending stiffness of the first region R1 of the guide wire 1 is smaller than the bending stiffness of the second region R2 (bending stiffness: first region R1<second region R2). In addition, since the tapered portion 42 extending from the second region R2 to the third region R3 gradually thickens from the front end side to the base end side, the stiffness gradually increases. Therefore, the bending stiffness of the second region R2 of the guide wire 1 is smaller than the bending stiffness of the third region R3 (bending stiffness: second region R2<third region R3). In this way, with respect to the guide wire 1 of this embodiment, the bending stiffness of the first region R1 located at the front end side is the smallest, and then the bending stiffness increases in the order of the second region R2 and the third region R3. It should be noted that the shape of the tapered portion 42 can also be adjusted to make the bending stiffness of the second region R2 equal to the bending stiffness of the third region R3 (bending stiffness: second region R2=third region R3).

[0063] As described above, according to the guide wire 1 of the first embodiment, in the length direction (axis O direction) of the core shaft 40, the front end of the second coil body 20 is located between the front end and the base end of the first coil body 10, and the base end of the second coil body 20 is located at a position closer to the base end side than the base end of the first coil body 10. Therefore, the guide wire 1 is configured to have the above-mentioned first region and second region from the front end side toward the base end side. Here, since the bending rigidity of the first coil body 10 is less than the bending rigidity of the second coil body 20, the bending rigidity of the first region R1 of the front end side is less than the bending rigidity of the second region R2. As a result, when the front end of the guide wire 1 is subjected to the resistance of the lesion or the inner wall of the blood vessel, the bend generated by the guide wire 1 can be easily generated in the first region R1 or at the boundary of the first region R1 and the second region R2. In addition, the bend generated by the front end of the guide wire 1 can be suppressed from expanding (developing) to the second region R2 located at the base end side. Therefore, according to the guide wire 1 of this embodiment, safety can be improved.

[0064] In addition, since the guide wire 1 of the first embodiment has the first fixing portion 51 that fixes the front end portion of the second coil body 20 and a portion of the first coil body 10, the torque transmission of the guide wire 1 (the performance of transmitting the operation of the guide wire 1 at the proximal portion to the front end side) can be improved. In addition, by having the first fixing portion 51, the bend generated by the guide wire 1 can be easily generated at a position closer to the front end side than the first fixing portion 51. As a result, the bend generated by the front end portion (i.e., the first region R1) of the guide wire 1 can be further suppressed from expanding to the second region R2 located at the base end side.

[0065] Moreover, according to the guidewire 1 of the first embodiment, since the core shaft 40 includes a flat portion 41 having a flat-plate-like outer shape at a position closer to the front end side than the tapered portion 42, the trimming performance of the guidewire 1 (performance indicating the ease of giving a shape when giving a bend or other shape to the front end of the guidewire 1 to guide the front end of the guidewire 1 to the target blood vessel) can be improved. In addition, since the core shaft 40 has a tapered portion 42 whose outer diameter is reduced from the base end toward the front end, the front end side of the guidewire 1 can be made soft. Furthermore, since the base end of the flat portion 41 is aligned with the front end of the second coil body 20 in the length direction of the core shaft 40 ( Figure 2 : position B), so that the stiffness difference between the first region R1 and the second region R2 can be made larger. As a result, the bend generated by the guide wire 1 can be more easily generated in the first region R1 or at the boundary between the first region R1 and the second region R2, and the bend generated at the front end of the guide wire 1 can be further suppressed from expanding to the second region R2 located at the base end side. Therefore, the safety of the guide wire 1 can be further improved, and the use of the guide wire 1 can be made more convenient.

[0066] Moreover, according to the guide wire 1 of the first embodiment, since the first fixing portion 51 fixes the first coil body 10 and the second coil body 20, but does not fix the core shaft 40, the flexibility of the guide wire 1 can be maintained. Similarly, since the third fixing portion 53 fixes the first coil body 10 and the core shaft 40, but does not fix the second coil body 20 and the third coil body 30, the flexibility of the guide wire 1 can be maintained. Similarly, since the fourth fixing portion 54 fixes the second coil body 20 and the core shaft 40, but does not fix the third coil body 30, the flexibility of the guide wire 1 can be maintained.

[0067] <Second embodiment>

[0068] Figure 6 1 is an explanatory diagram illustrating the structure of the guide wire 1A of the second embodiment. The guide wire 1A of the second embodiment has a first fixing portion 51A in the structure described in the first embodiment instead of the first fixing portion 51. The first fixing portion 51A is arranged at the front end of the second coil body 20, and in addition to fixing the front end of the second coil body 20 and a part of the first coil body 10, it also fixes a part of the core shaft 40 (in the example shown in the figure, the front end of the tapered portion 42) and keeps them as a whole.

[0069] In this way, the structure of the guide wire 1A can be changed in various ways, and the first fixed portion 51A can not only fix the first coil body 10 and the second coil body 20, but also fix the mandrel 40. In addition, the first fixed portion 51A can also fix a part of the third coil body 30 in addition to fixing the front end of the second coil body 20 and a part of the first coil body 10. In the guide wire 1A of such a second embodiment, the same effect as the first embodiment described above can also be achieved. In addition, according to the guide wire 1A of the second embodiment, the first fixed portion 51A also fixes the front end of the second coil body 20 and a part of the mandrel 40. Therefore, the bend generated by the guide wire 1A can be easily generated at a position closer to the front end side (i.e., the first region R1) than the first fixed portion 51A, and the bend generated by the front end of the guide wire 1A can be further suppressed from expanding to the second region R2 located at the base end side.

[0070] <Third Embodiment>

[0071] Figure 7 2 is an explanatory diagram illustrating the structure of a guide wire 1B according to the third embodiment. Figure 7 In the third embodiment, the guide wire 1B is exemplified. Figure 2The guide wire 1B of the third embodiment has a core shaft 40B in place of the core shaft 40 in the structure described in the first embodiment. The core shaft 40B has a thin-diameter portion 41B in place of the flat plate portion 41 described in the first embodiment. The thin-diameter portion 41B is a substantially cylindrical portion having a substantially constant outer diameter from the base end to the front end, such as Figure 7 The outer diameter of the narrow portion 41B is the same as the smallest diameter portion of the tapered portion 42 .

[0072] In this way, the structure of the core shaft 40B can be changed in various ways, and the core shaft 40B may not have the flat plate portion 41 described in the first embodiment. In addition, the core shaft 40B may not have the thin diameter portion 41B described in the third embodiment, and the front end of the tapered portion 42 is fixed by the front end tip 61. In the guide wire 1B of the third embodiment, the same effect as the first embodiment can be achieved.

[0073] <Fourth embodiment>

[0074] Figure 8 1 is an explanatory diagram illustrating the structure of a guide wire 1C according to a fourth embodiment. The guide wire 1C according to the fourth embodiment further includes a second fixing portion 52 in addition to the respective structures described in the first embodiment.

[0075] The second fixing portion 52 is arranged between the first fixing portion 51 and the third fixing portion 53 in the direction of the axis O. In other words, the second fixing portion 52 is arranged at an arbitrary position closer to the base end side than the front end of the second coil body 20 and closer to the front end side than the base end of the first coil body 10. The second fixing portion 52 fixes a part of the core shaft 40 (specifically, a part of the tapered portion 42), a part of the first coil body 10, a part of the second coil body 20, and a part of the third coil body 30, and keeps them as a whole. The second fixing portion 52, like the front end tip 61, etc., can be formed by any bonding agent, such as metal solder such as silver solder, gold solder, zinc, Sn-Ag alloy, Au-Sn alloy, or adhesive such as epoxy resin adhesive.

[0076] In this way, the structure of the guide wire 1C can be changed in various ways, and it can also have a second fixing portion 52 that fixes the core shaft 40 and the first to third coil bodies 10, 20, and 30. In such a guide wire 1C of the fourth embodiment, the same effect as the first embodiment described above can also be achieved. In addition, according to the guide wire 1C of the fourth embodiment, since it has a second fixing portion 52 that fixes a part of the core shaft 40, a part of the first coil body 10, a part of the second coil body 20, and a part of the third coil body 30 (tubular body), the torque transmission of the guide wire 1C can be improved. In addition, by fixing the first coil body 10, the second coil body 20, and the third coil body 30 to the core shaft 40 through the second fixing portion 52, it is possible to suppress the position of the first coil body 10, the second coil body 20, and the third coil body 30 from moving in the length direction (in other words, it is possible to suppress the first coil body 10, the second coil body 20, and the third coil body 30 from shifting from each other).

[0077] <Fifth embodiment>

[0078] Fig. 9 1 is an explanatory diagram illustrating the structure of a guide wire 1D according to a fifth embodiment. The guide wire 1D according to the fifth embodiment does not include the first fixing portion 51 in the structure described in the fourth embodiment. In this way, the structure of the guide wire 1D can be changed in various ways, and a part of the above-mentioned fixing portion can be omitted. In the example shown in the figure, although the first fixing portion 51 is omitted, the third fixing portion 53 or the fourth fixing portion 54 can be omitted instead of the first fixing portion 51, or the third fixing portion 53 or the fourth fixing portion 54 can be omitted together with the first fixing portion 51. In such a guide wire 1D according to the fifth embodiment, the same effect as the above-mentioned first and fourth embodiments can be achieved.

[0079] <Sixth embodiment>

[0080] Fig.10 1 is an explanatory diagram illustrating the structure of a guide wire 1E according to the sixth embodiment. The guide wire 1E according to the sixth embodiment includes a tube body 30E instead of the third coil body 30 in the structure described in the first embodiment.

[0081] The tubular body 30E is a roughly cylindrical member having openings at the front end and the base end and having an inner cavity connecting the two openings on the inside. The tubular body 30E can be formed by any resin material or any metal material. The tubular body 30E is similar to the third coil body 30 of the first embodiment, and is arranged at a radially outer side than the second coil body 20, and surrounds a part of the core shaft 40, the first coil body 10 and the second coil body 20. The front end of the tubular body 30E is fixed to the core shaft 40 and the first coil body 10 by the front end tip 61, and the base end of the tubular body 30E is located at a position closer to the base end side than the base end of the second coil body 20, and is fixed to the core shaft 40 by the base end side fixing portion 62. In this embodiment, the tubular body 30E is equivalent to a "tubular body".

[0082] In this way, the structure of the guide wire 1E can be changed in various ways, and the structure of covering the first coil body 10 and the second coil body 20 with a tube 30E can also be replaced by a coil body formed by winding a wire to cover the first coil body 10 and the second coil body 20. It should be noted that from the viewpoint of maintaining the shape of the front end side of the guide wire 1E, the thickness T30 of the tube 30E can also be greater than the outer diameter Φ11 of the wire 11, and can also be greater than the outer diameter Φ21 of the wire 21. However, the thickness T30 of the tube 30E can also be less than at least one of the outer diameter Φ11 and the outer diameter Φ21. In such a guide wire 1E of the sixth embodiment, the same effect as the first embodiment described above can also be achieved. In addition, according to the guide wire 1E of the sixth embodiment, the sliding property of the guide wire 1E in the blood vessel can be improved.

[0083] <Seventh embodiment>

[0084] Fig.11 1 is an explanatory diagram illustrating the structure of the guide wire 1F of the seventh embodiment. The guide wire 1F of the seventh embodiment further includes a covering layer 70 in the structure described in the sixth embodiment. The covering layer 70 is a thin film that covers the outer surface of the front end tip 61, the outer surface of the tube body 30E, the outer surface of the base end side fixing portion 62, and the outer surface of the core shaft 40 located closer to the base end side than the base end side fixing portion 62. The covering layer 70 can be formed of a hydrophilic or hydrophobic resin, for example. The film thickness of the covering layer 70 can be determined arbitrarily.

[0085] In this way, the structure of the guide wire 1F can be changed in various ways, and can also have other structures not mentioned in the above text (for example, the covering layer 70). In such a guide wire 1F of the seventh embodiment, the same effect as the first embodiment and the sixth embodiment can also be achieved. In addition, according to the guide wire 1F of the seventh embodiment, since the guide wire 1F has the covering layer 70 covering the outer surface of the front end tip 61, the outer surface of the tubular body 30E (tubular body), and the outer surface of the core shaft 40 located at a position closer to the base end side than the tubular body 30E, the sliding property of the guide wire 1F in the blood vessel can be further improved.

[0086] <Eighth Embodiment>

[0087] Fig.12 The guide wire 1G of the eighth embodiment includes a third coil body 30G instead of the third coil body 30 and a proximal end fixing portion 62G instead of the proximal end fixing portion 62 in the structure described in the first embodiment.

[0088] The third coil body 30G surrounds the entire core shaft 40, the first coil body 10 and the second coil body 20. In the direction of the axis O, the front end of the third coil body 30G is located at the same position as the front end of the first coil body 10, and the base end of the third coil body 30G is located at the same position as the base end of the core shaft 40. It should be noted that in the present embodiment, "same" means approximately the same, which means that differences caused by manufacturing errors, etc. are allowed. The base end side fixing portion 62G is arranged at the base end of the third coil body 30G, and the base end of the third coil body 30G and the base end of the core shaft 40 (specifically, the base end of the thick diameter portion 43) are kept as a whole.

[0089] Like this, the structure of guide wire 1G can be variously changed, and can also be a structure in which the entire mandrel 40 is surrounded by a tubular body (in the illustrated example, the third coil body 30G). In addition, in guide wire 1G, it is also possible to have a fixing portion that fixes a part of the third coil body 30G and a part of the thick-diameter portion 43. In such a guide wire 1G of the eighth embodiment, the same effect as the first embodiment described above can also be achieved. In addition, according to the guide wire 1G of the eighth embodiment, a guide wire 1G that is covered by a tubular body as a whole can be provided.

[0090] <Ninth embodiment>

[0091] Fig.13It is an explanatory diagram illustrating the structure of the guide wire 1H of the ninth embodiment. The guide wire 1H of the ninth embodiment has a core shaft 40H instead of the core shaft 40 in the structure described in the first embodiment. The core shaft 40H has a flat plate portion 41H instead of the flat plate portion 41 described in the first embodiment. The length of the flat plate portion 41H in the direction of the axis O (in other words, the length direction of the core shaft 40H) is longer than the flat plate portion 41 described in the first embodiment. Therefore, the position B2 of the base end of the flat plate portion 41H is closer to the base end side than the position B1 of the front end of the second coil body 20.

[0092] Like this, the structure of mandrel 40H can carry out various changes, and the position B2 of the base end of flat plate 41H can also be inconsistent with the position B1 of the front end of the second coil body 20.In the illustrated example, although the flat plate 41H longer than the flat plate 41 described in the first embodiment is illustrated, the length of flat plate 41H can also be shorter than the flat plate 41 described in the first embodiment.In this case, the position B2 of the base end of flat plate 41H is closer to the front end side than the position B1 of the front end of the second coil body 20.In the guide wire 1H of such the 9th embodiment, the same effect as the above-mentioned first embodiment can also be achieved.In addition, according to the guide wire 1H of the 9th embodiment, the length of the part that functions as the ribbon for shape imparting can be freely changed.

[0093] <Tenth embodiment>

[0094] Fig.14 The guide wire 1I of the tenth embodiment may also include a second coil body 20I instead of the second coil body 20, a base end fixing portion 62I instead of the base end fixing portion 62, and no fourth fixing portion 54 in the structure described in the first embodiment.

[0095] In the direction of the axis O, the front end of the second coil body 20I is located between the front end and the base end of the first coil body 10, and the base end of the second coil body 20I is located at the same position as the base end of the third coil body 30. It should be noted that in this embodiment, "same" means approximately the same, which means that differences caused by manufacturing errors, etc. are allowed. The base end side fixing portion 62I is arranged at the base end of the third coil body 30, and holds the base end of the third coil body 30, the base end of the second coil body 20I and a part of the core shaft 40 as a whole. Fig.14 As shown, in the guide wire 1I of the tenth embodiment, there is no region where the core shaft 40 is surrounded only by the third coil body 30 , that is, there is no third region R3 .

[0096] In this way, the structure of the guide wire 1I can be changed in various ways, the base end of the second coil body 20I and the base end of the third coil body 30 are located at the same position, and the third region R3 may not exist. In addition, in the guide wire 1I, a fixing portion that fixes a part of the core shaft 40, a part of the second coil body 20I, and a part of the third coil body 30 can also be set at a position closer to the base end side than the third fixing portion 53. In the guide wire 1I of such a tenth embodiment, the same effect as the first embodiment described above can also be achieved.

[0097] <Eleventh Embodiment>

[0098] Fig.15 The guide wire 1J of the eleventh embodiment has a distal tip 61J instead of the distal tip 61 in the structure described in the first embodiment, and does not have the third coil body 30 and the proximal end fixing portion 62 described in the first embodiment.

[0099] Since the guide wire 1J does not have the third coil body 30, a portion of the front end side of the first coil body 10 and the second coil body 20 are not covered by the third coil body 30 but are exposed. In addition, the guide wire 1J has a first region R1 and a second region R2, but does not have a third region R3 (the region where the core shaft 40 is surrounded by the third coil body 30). The front end tip 61J is arranged at the front end of the first coil body 10, and the front end of the first coil body 10 and the front end of the core shaft 40 are kept as a whole. It should be noted that the guide wire 1J may also have a hydrophilic or hydrophobic covering layer. In this case, the covering layer may be a covering layer that covers the outer surface of the front end tip 61J, a portion of the front end side of the first coil body 10 ( Fig.15 : exposed portion), the outer surface of the second coil body 20, the outer surface of the first fixing portion 51, the outer surface of the fourth fixing portion 54, and a thin film of the outer surface of the core shaft 40 located closer to the base end side than the fourth fixing portion 54.

[0100] In this way, the structure of the guide wire 1J can be changed in various ways, and the third coil body 30 can be omitted so as not to have the third region R3. In such a guide wire 1J of the eleventh embodiment, the same effect as the first embodiment described above can be achieved. In addition, according to the guide wire 1J of the eleventh embodiment, the guide wire 1J can be made thinner and the number of components constituting the guide wire 1J can be reduced, thereby reducing the man-hours for manufacturing the guide wire 1J and reducing the manufacturing cost.

[0101] <Modification of the present embodiment>

[0102] The present invention is not limited to the above-described embodiment, and can be implemented in various forms without departing from the gist of the present invention. For example, the following modifications are also possible.

[0103] [Modification 1]

[0104] In the above-mentioned first to eleventh embodiments, the structures of the guide wires 1, 1A to 1J are illustrated. However, the structure of the guide wire 1 can be changed in various ways. For example, according to the performance required of the guide wire 1, the core shaft 40 of the guide wire 1 can be appropriately provided with a thin-diameter portion, a thick-diameter portion, a flat portion, a tapered portion, etc., and the flat portion 41 and the tapered portion 42 mentioned above can also be omitted. For example, for the guide wire 1C, at least one or more of the first fixing portion 51, the second fixing portion 52, the third fixing portion 53 and the fourth fixing portion 54 can also be omitted.

[0105] [Modification 2]

[0106] In the above-mentioned first embodiment to the eleventh embodiment, the structures of the first coil body to the third coil body 10, 20, 20I, 30, 30G and the tube body 30E are illustrated. However, their structures can be changed in various ways. For example, a roughly cylindrical tube body can also be used to replace the first coil body 10 and / or the second coil body 20. For example, at least one of the first coil body 10, the second coil body 20 and the third coil body 30 can also be buried in the thick wall portion of the roughly cylindrical tube body.

[0107] [Variation 3]

[0108] The structures of the guidewires of the first to eleventh embodiments and the structures of the guidewires of the above-mentioned modifications 1 and 2 may be appropriately combined. For example, the guidewires 1 of the third to eleventh embodiments may also include the first fixing portion 51A described in the second embodiment. For example, the guidewires 1 of the second, fourth to eleventh embodiments may also include the thin-diameter portion 41B described in the third embodiment. For example, the guidewires 1 of the second, third, fifth to tenth embodiments may also include the second fixing portion 52 described in the fourth embodiment. For example, the guidewires 1 of the second to fifth, eighth to tenth embodiments may also include the tube body 30E described in the sixth embodiment. For example, the guidewires 1 of the second to sixth, eighth to tenth embodiments may also include the covering layer 70 described in the seventh embodiment. For example, the guidewires 1 of the second to seventh, ninth and tenth embodiments may also include the third coil body 30G described in the eighth embodiment.

[0109] As described above, the present invention is described based on the embodiments and variations, but the embodiments described above are examples for facilitating understanding of the present invention and are not intended to limit the present invention. Any modifications, improvements, and equivalent substitutions made within the spirit of the present invention and the scope of the claims shall be included in the protection scope of the present invention. In addition, if the technical features are not described as indispensable in this specification, they may be appropriately deleted.

[0110] Description of Reference Numerals

[0111] 1. 1A~1J…guide wire

[0112] 2…Measurement device

[0113] 3…Load sensor

[0114] 4…Handle

[0115] 5…Measurement object

[0116] 10…First coil body

[0117] 11…Wire

[0118] 20, 20I…Second coil body

[0119] 21…Wire

[0120] 30, 30G…The third coil body

[0121] 30E...tube body

[0122] 31…Wire

[0123] 40, 40B, 40H… spindle

[0124] 41, 41H… Flat plate

[0125] 41B…Thin diameter part

[0126] 42…Conical part

[0127] 43…Rough diameter

[0128] 51, 51A…first fixing portion

[0129] 52…Second fixing portion

[0130] 53…third fixing portion

[0131] 54…Fourth fixing portion

[0132] 61, 61J…front end

[0133] 62, 62G, 62I ... proximal end fixing portion

[0134] 70…cover

Claims

1. A guide wire, comprising: A mandrel having a long strip shape; a first coil body arranged to surround a front end portion of the core shaft; a second coil body, the second coil body being arranged radially outwardly of the first coil body; a tubular body, the tubular body being arranged radially outward of the second coil body; A front end tip, the front end tip fixes the front end of the mandrel, the front end of the tubular body, and the front end of the first coil body; as well as a second fixing portion, the second fixing portion fixing a portion of the core shaft, a portion of the first coil body, a portion of the second coil body, and a portion of the tubular body; Wherein, in the length direction of the mandrel, The front end of the second coil body is located between the front end and the base end of the first coil body. The base end of the second coil body is located closer to the base end side than the base end of the first coil body. The bending stiffness of the first coil body is smaller than the bending stiffness of the second coil body.

2. The guide wire according to claim 1, wherein: The guide wire further includes a first fixing portion that fixes a distal end portion of the second coil body and a portion of the first coil body.

3. The guide wire according to claim 2, wherein: The first fixing portion also fixes the front end portion of the second coil body and a portion of the core shaft.

4. The guide wire according to any one of claims 1 to 3, wherein: The mandrel has: a tapered portion whose outer diameter is reduced from a base end toward a front end; and a flat plate portion, the flat plate portion being disposed closer to the front end side than the tapered portion and having a flat plate-like outer shape, The base end of the flat plate portion and the front end of the second coil body are aligned in the longitudinal direction of the core axis.

5. The guide wire according to any one of claims 1 to 3, wherein: The proximal end of the tubular body is located on the proximal side of the proximal end of the second coil body.

6. The guide wire according to claim 4, wherein: The proximal end of the tubular body is located on the proximal side of the proximal end of the second coil body.

7. The guide wire according to any one of claims 1 to 3, wherein: The guide wire also has: A covering layer covers an outer surface of the front end tip, an outer surface of the tubular body, and an outer surface of the mandrel located closer to the base end side than the tubular body.

Images