Medical wire

The medical wire's flexible design allows for controlled navigation and adjustable rigidity, reducing the need for multiple guidewires and shortening operation time in navigating chronic total occlusion lesions.

WO2025142290A1PCT designated stage expired Publication Date: 2025-07-03NHK SPRING CO LTD
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Patent Information

Application Number
PCT/JP2024/042004
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2023-12-26
Filing Date
2024-11-27
Publication Date
2025-07-03

AI Technical Summary

Technical Problem

Conventional guidewires require multiple insertions and removals with different bending rigidities to navigate through chronic total occlusion lesions, increasing operation time and complexity.

Method used

A medical wire design with a flexible tubular body and operation wire, where the operation wire's front end is fixed off-center, allowing for controlled bending and rigidity adjustment by pulling the wire, eliminating the need for multiple guidewires.

Benefits of technology

Reduces operation time by enabling controlled navigation through blood vessels with adjustable bending rigidity without needing to switch guidewires, simplifying the procedure.

✦ Generated by Eureka AI based on patent content.

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Abstract

The present invention comprises: a first flexible tube body (11) that extends in the longitudinal direction and is formed so as to be able to bend and deform; an operation wire (12) that extends in the longitudinal direction and is inserted into the first flexible tube body (11); and a support body (14) that is fixed to the rear end of the first flexible tube body (11), wherein a front end (12a) of the operation wire (12) is fixed to the front end of the first flexible tube body (11) in a state of being offset in one radial direction from the central axis (O1) of the first flexible tube body (11), the front end opening of the first flexible tube body is closed by a fixing member (25), the front end of the operation wire is embedded in the fixing member, and an engaging protrusion (12b), which protrudes further in the radial direction than the portion located between the front end and the rear end of the operation wire, is formed on the front end of the operation wire.
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Description

Medical Wire

[0001] The present invention relates to a medical wire such as a guidewire. This application claims priority to Japanese Patent Application No. 2023-219250, filed on December 26, 2023, the contents of which are incorporated herein by reference.

[0002] Conventionally, as shown in Patent Document 1 below, a guidewire has been known as a medical wire, comprising a first flexible tubular body (outer flexible tubular body 4) extending in the front-rear direction and formed to be bendable, a manipulation wire (core shaft) extending in the front-rear direction and inserted inside the first flexible tubular body, and a support fixed to the rear end of the first flexible tubular body. Generally, a guidewire is inserted into a blood vessel and used to guide a balloon or a stent to a chronic total occlusion lesion or the like in a state where the guidewire penetrates a chronic total occlusion lesion or the like in the blood vessel. When penetrating a chronic total occlusion lesion or the like with the guidewire, the following procedure is taken, for example: First, the guidewire inserted into a microcatheter is advanced into the blood vessel. When the guidewire reaches a chronic total occlusion lesion or the like in the blood vessel, the previously used guidewire is removed while leaving the microcatheter in the blood vessel. Then, a new guidewire with a higher tip load or the like than the first guidewire is inserted into the microcatheter and pierced into the chronic total occlusion lesion or the like, and the chronic total occlusion lesion or the like is penetrated with the guidewire and the microcatheter. Thereafter, the microcatheter is left in the blood vessel, having penetrated the chronic total occlusion lesion, etc., and the guidewire with the high tip load, etc. is removed. The original guidewire with the low tip load, etc. is reinserted into the microcatheter, and after it has reached a position where it penetrates the chronic total occlusion lesion, etc., the microcatheter is removed, leaving the guidewire in place.

[0003] Japanese Patent Application Publication No. 2011-199

[0004] With conventional guidewires, in order to penetrate a chronic total occlusion or the like, it is necessary to use guidewires with different bending stiffnesses, such as tip loads, by inserting and removing them from blood vessels, etc., and replacing them accordingly. Furthermore, in order to select a blood vessel at a vascular bifurcation and advance into the target blood vessel before reaching a chronic total occlusion or the like, it is necessary to insert and remove the guidewire from the blood vessel and fine-tune the curvature of the front end of the guidewire (the bending tendency called preshape) outside the body. For this reason, there is a demand for shortening the surgical time.

[0005] The present invention provides a medical wire that can shorten the time required for surgery.

[0006] A medical wire according to a first aspect of the present invention comprises a first flexible tubular body extending in the front-rear direction and formed to be bendable and deformable, a manipulation wire extending in the front-rear direction and inserted inside the first flexible tubular body, and a support body fixed to the rear end of the first flexible tubular body, wherein the front end of the manipulation wire is fixed to the front end of the first flexible tubular body in a state spaced apart in one radial direction from the central axis of the first flexible tubular body, the front end opening of the first flexible tubular body is closed by a fixing member, the front end of the manipulation wire is embedded in the fixing member, and a locking protrusion is formed on the front end of the manipulation wire that protrudes radially from a portion of the manipulation wire located between the front end and rear end.

[0007] A medical wire according to a second aspect of the present invention includes a first flexible tubular body extending in the front-rear direction and formed to be bendable and deformable, an operation wire extending in the front-rear direction and inserted inside the first flexible tubular body, and a support body fixed to the rear end of the first flexible tubular body, wherein the front end of the operation wire is fixed to the front end of the first flexible tubular body in a state spaced apart in one radial direction from the central axis of the first flexible tubular body, the front end opening of the first flexible tubular body is closed by a fixing member, the front end of the operation wire is embedded in the fixing member, and the front end of the operation wire is provided with a protruding portion that radially straddles the edge of the front end opening of the first flexible tubular body and is engaged with the first flexible tubular body.

[0008] According to the medical wires of the first and second aspects of the present invention, the front end of the manipulation wire is fixed to the front end of the first flexible tubular body while being spaced apart in one radial direction from the central axis of the first flexible tubular body. Therefore, when the manipulation wire is pulled rearward relative to the support portion, the first flexible tubular body undergoes compressive deformation and bends in a specific radial direction. By manipulating the manipulation wire and bending the front end of the medical wire in a specific direction, a blood vessel can be selected at a vascular bifurcation and the medical wire can be advanced into the target blood vessel. This reduces the physician's dependence on the physician's sense of manipulation when guiding the medical wire along the blood vessel to reach a chronic total occlusion lesion or the like, and eliminates the need to insert or remove the medical wire from the blood vessel to fine-tune the curvature of the front end of the medical wire outside the body. Furthermore, when the manipulation wire is pulled rearward relative to the support portion, the front ends of the manipulation wire and the first flexible tubular body move rearward, compressing and deforming the first flexible tubular body in the front-to-rear direction between the support portion and the first flexible tubular body, thereby increasing the bending rigidity of the first flexible tubular body. Therefore, by manipulating the manipulation wire while the medical wire is inserted into a blood vessel, the bending rigidity of the first flexible tubular body can be changed. As a result, when penetrating a chronic total occlusion or the like with the medical wire, the bending rigidity of the first flexible tubular body is kept low until the medical wire enters the blood vessel and reaches the chronic total occlusion or the like within the blood vessel. Then, when the medical wire is thrust into the chronic total occlusion or the like and penetrates the chronic total occlusion or the like with the medical wire, the manipulation wire is pulled rearward relative to the support portion to increase the bending rigidity of the first flexible tubular body. After penetrating the chronic total occlusion or the like with the medical wire, the manipulation of the manipulation wire can be released to return the bending rigidity of the first flexible tubular body to its original low state. This eliminates the need to use different medical wires with different bending rigidities by inserting and removing them from the blood vessel or the like to penetrate the chronic total occlusion or the like. As a result, the surgical time can be shortened.

[0009] According to the medical wire of the first aspect of the present invention, the front end of the operation wire is embedded in a fixing member that closes the front end opening of the first flexible tubular body, and a locking protrusion is formed on the front end of the operation wire, protruding radially from a portion of the operation wire located between the front end and the rear end. Therefore, the locking protrusion hooks onto the fixing member in the front-rear direction, preventing the front end of the operation wire from coming off the fixing member during operation of the operation wire. According to the medical wire of the second aspect of the present invention, the front end of the operation wire is embedded in a fixing member that closes the front end opening of the first flexible tubular body, and a protruding portion is formed on the front end of the operation wire, spanning the edge of the front end opening of the first flexible tubular body in the radial direction and locked to the first flexible tubular body. Therefore, the protruding portion hooks onto the first flexible tubular body in the front-rear direction, preventing the front end of the operation wire from coming off the fixing member during operation of the operation wire.

[0010] A second flexible tube extending in the front-to-rear direction and formed to be bendable and deformable is inserted inside the first flexible tube, the operating wire is inserted inside the second flexible tube, the central axis of the second flexible tube and the front end of the operating wire are spaced apart from the central axis of the first flexible tube in one radial direction, the front end of the second flexible tube is fixed to at least one of the front ends of the first flexible tube and the operating wire, and the rear end of the second flexible tube, located rearward of the front end, is fixed to at least one of the support body and the rear end of the first flexible tube.

[0011] Because the second flexible tubular body is provided, when the manipulation wire is pulled rearward relative to the support part, the first and second flexible tubular bodies are compressed and deformed while bending in one radial direction, which makes it possible to easily adjust (design) the relationship between the manipulation force on the manipulation wire and the bending shape of the front end of the medical wire while maintaining the outer diameter of the medical wire, for example.

[0012] According to the above aspect of the present invention, the time required for surgery can be shortened.

[0013] Fig. 1 is a longitudinal cross-sectional view of a medical wire according to a first embodiment; Fig. 2 is a partial longitudinal cross-sectional view of a first modified example of the medical wire according to the first embodiment; Fig. 3 is a partial longitudinal cross-sectional view of a second modified example of the medical wire according to the first embodiment; Fig. 4 is a longitudinal cross-sectional view of a medical wire according to a second embodiment.

[0014] A first embodiment of the medical wire will be described below with reference to FIG. 1A . The medical wire 1 is a guidewire including a first flexible tubular body 11, an operating wire 12, an operating section 13, a support member 14, and a second flexible tubular body 15. The first flexible tubular body 11, the operating wire 12, the operating section 13, the support member 14, and the second flexible tubular body 15 are formed of, for example, a metal material. Note that the materials forming the first flexible tubular body 11, the operating wire 12, the operating section 13, the support member 14, and the second flexible tubular body 15 may be changed as appropriate. The operating section 13 and the second flexible tubular body 15 may not be provided.

[0015] The operation unit 13 and the support body 14 are formed in a cylindrical shape and disposed coaxially with the central axis O1 of the first flexible tubular body 11. Hereinafter, the side where the first flexible tubular body 11 is located with respect to the support body 14 in the direction in which the central axis O1 extends will be referred to as the front side, the side where the operation unit 13 is located with respect to the support body 14 in the direction in which the central axis O1 extends will be referred to as the rear side, and the direction in which the central axis O1 extends will be referred to as the front-rear direction. A direction intersecting the central axis O1 as viewed from the front-rear direction will be referred to as the radial direction, and a direction going around the central axis O1 as viewed from the front-rear direction will be referred to as the circumferential direction.

[0016] The first flexible tubular body 11 extends in the front-rear direction and is formed to be bendable. The first flexible tubular body 11 is a coil spring extending in the front-rear direction. The outer diameter of the first flexible tubular body 11 is large enough to be inserted into a blood vessel (e.g., 0.2 mm to 1.0 mm). The outer shape and size of the first flexible tubular body 11 as viewed in the front-rear direction are constant over the entire length in the front-rear direction. The diameter of the wire material forming the first flexible tubular body 11 is constant over the entire length.

[0017] The diameter of the wire forming the first flexible tubular body 11 does not have to be constant along its entire length, and the outer shape and size of the first flexible tubular body 11 as viewed in the front-rear direction do not have to be constant along its entire length in the front-rear direction. For example, the outer diameter of the first flexible tubular body 11 may decrease toward the front. The first flexible tubular body 11 is not limited to a coil spring, and may be, for example, a tubular body having a peripheral wall that extends continuously along its entire length in both the front-rear direction and the circumferential direction.

[0018] The support body 14 is fixed to the rear end of the first flexible tubular body 11. The support body 14 extends in the front-rear direction and is formed to be bendable. The rear end opening edge of the first flexible tubular body 11 abuts against the front end opening edge of the support body 14 in the front-rear direction. The front end of the support body 14 and the rear end of the first flexible tubular body 11 are fixed together by, for example, soldering, brazing, adhesive, or crimping. In the illustrated example, a cylindrical intermediate fixing member 23 made of, for example, solder, brazing material, or adhesive extends forward from the front end of the support body 14. The outer peripheral surface of the intermediate fixing member 23 is seamlessly connected to the outer peripheral surfaces of the support body 14 and the first flexible tubular body 11 in the front-rear direction.

[0019] The outer diameter of the support 14 is equal to the outer diameter of the first flexible tubular body 11 and is large enough to be inserted into a blood vessel (e.g., 0.2 mm to 1.0 mm). The outer shape and size of the support 14 as viewed in the front-rear direction are constant over the entire length in the front-rear direction. Note that the outer shape and size of the support 14 as viewed in the front-rear direction do not have to be constant over the entire length in the front-rear direction. For example, the outer diameter of the support 14 may decrease toward the front. The outer shapes and sizes of the support 14 and the first flexible tubular body 11 as viewed in the front-rear direction may be different from each other. In this case, it is preferable that the support 14 does not protrude radially outward from the outer circumferential surface of the first flexible tubular body 11 as viewed in the front-rear direction.

[0020] The operation unit 13 is provided behind the support body 14. The operation unit 13 protrudes rearward from the support body 14. The operation unit 13 is provided so as to be movable in the front-rear direction relative to the support body 14. In the illustrated example, the rear end of the support body 14 is inserted into the front portion of the operation unit 13. Note that the front end opening edge of the operation unit 13 and the rear end opening edge of the support body 14 may face each other in the front-rear direction, or the front portion of the operation unit 13 may be inserted into the rear end of the support body 14. The rear end of the operation wire 12 is fixed to the operation unit 13 by, for example, soldering, brazing, adhesive, or crimping. In the illustrated example, the rear end opening of the operation unit 13 is closed by a rear fixing member 24 made of, for example, a solder material, a brazing material, or an adhesive, and the rear end of the operation wire 12 is embedded in the rear fixing member 24.

[0021] The operation wire 12 extends in the front-rear direction and is inserted inside the first flexible tubular body 11. The operation wire 12 is formed to be elastically deformable. A front end 12a of the operation wire 12 is fixed to the front end of the first flexible tubular body 11 by, for example, soldering, brazing, bonding, or crimping, while being spaced apart in one radial direction from the central axis O1. Note that multiple operation wires 12 may be provided at intervals in the circumferential direction. The operation wire 12 extends straight in the front-rear direction. Note that the operation wire 12 may extend in the front-rear direction while being bent, for example. A rear portion of the operation wire 12 protrudes rearward from the support body 14.

[0022] The front end opening of the first flexible tubular body 11 is closed by a front fixing member 25 (fixing member) made of, for example, solder, brazing material, or adhesive. The outer peripheral surface of the front fixing member 25 is connected to the outer peripheral surface of the first flexible tubular body 11 without any step in the front-to-rear direction. The front end 12a of the operation wire 12 is embedded in the front fixing member 25.

[0023] The bending rigidity of the intermediate section 11a of the first flexible tubular body 11, which is located between the front end (front fixing member 25) and the rear end (middle fixing member 23), decreases from the rear to the front. In the example shown, the first flexible tubular body 11 includes a first hard tubular section 22 having high bending rigidity, and a pair of first soft tubular sections 21 which have lower bending rigidity than the first hard tubular section 22 and sandwich the first hard tubular section 22 in the front-to-rear direction. Of the pair of first soft tubular sections 21, the number of turns of the first soft tubular section 21 located on the front side is greater than the number of turns of the first soft tubular section 21 located on the rear side. Note that the number of turns of the former may be equal to or less than the number of turns of the latter.

[0024] The first soft tube section 21 is formed so that the distance (inter-wire gap) between adjacent wire members in the front-to-rear direction is wider than that of the first hard tube section 22. As a result, the bending rigidity of the first soft tube section 21 is smaller than that of the first hard tube section 22, making it easier to flex flexibly to follow the bending of the blood vessel. In the illustrated example, adjacent wire members in the front-to-rear direction in the first hard tube section 22 abut against each other. In other words, the first hard tube section 22 is formed as a tightly wound coil spring. As a result, in the intermediate section 11a of the first flexible tube 11, the first hard tube section 22 is easier to flex flexibly to follow the bending deformation of the first soft tube section 21.

[0025] Of the pair of first soft tube sections 21, the front portion of the first soft tube section 21 located on the front side constitutes the front end portion of the first flexible tube 11 joined or adhered to the front fixing member 25, and the rear portion of this first soft tube section 21 is located between the front fixing member 25 and the intermediate fixing member 23. Of the pair of first soft tube sections 21, the first soft tube section 21 located on the rear side is joined or adhered over its entire length to the intermediate fixing member 23. Therefore, of the pair of first soft tube sections 21, the intermediate section 11a located between the front fixing member 25 and the intermediate fixing member 23 is composed of the entire first hard tube section 22 and the rear portion of the first soft tube section 21 located on the front side of the pair of first soft tube sections 21. As a result, the bending rigidity of the intermediate section 11a of the first flexible tube 11 decreases stepwise from the rear to the front. The bending rigidity of the intermediate portion 11a of the first flexible tubular body 11 may decrease linearly from the rear to the front. In the illustrated example, the length in the front-rear direction of the first hard tubular portion 22 is longer than the length in the front-rear direction of the rear portion of the first soft tubular portion 21 located on the front side of the pair of first soft tubular portions 21. The length of the former may be shorter than the length of the latter.

[0026] The second flexible tubular body 15 extends in the front-rear direction and is formed to be bendable. The second flexible tubular body 15 is inserted inside the first flexible tubular body 11. The front end of the second flexible tubular body 15 is fixed to at least one of the front ends of the first flexible tubular body 11 and the operation wire 12, and the rear end of the second flexible tubular body 15, which is located rearward of the front end, is fixed to at least one of the support body 14 and the rear end of the first flexible tubular body 11. The second flexible tubular body 15 protrudes in both the front-rear direction from the first flexible tubular body 11. Note that the second flexible tubular body 15 does not have to protrude in the front-rear direction from the first flexible tubular body 11.

[0027] At least one of the first flexible tubular body 11 and the second flexible tubular body 15 is a coil spring extending in the front-rear direction. In the illustrated example, both the first flexible tubular body 11 and the second flexible tubular body 15 are coil springs extending in the front-rear direction. The winding directions of the first flexible tubular body 11 and the second flexible tubular body 15 are opposite to each other. However, the winding directions of the first flexible tubular body 11 and the second flexible tubular body 15 may be the same as each other. Either one of the first flexible tubular body 11 and the second flexible tubular body 15 is not limited to a coil spring and may be, for example, a tubular body having a peripheral wall that extends continuously over the entire length in both the front-rear direction and the circumferential direction.

[0028] The bending rigidity of the intermediate section 15a of the second flexible tube 15, which is located between the front end section (front fixing member 25) and the rear section (middle fixing member 23), decreases from rear to front. In the illustrated example, the second flexible tube 15 is configured by connecting a second soft tube section 31, which has low bending rigidity, and a second hard tube section 32, which has higher bending rigidity than the second soft tube section 31, in this order from front to rear. The second soft tube section 31 protrudes forward from the first flexible tube 11, and the second hard tube section 32 protrudes rearward from the first flexible tube 11. The length of the second soft tube section 31 in the front-to-rear direction is slightly shorter than the length of the second hard tube section 32 in the front-to-rear direction.

[0029] The second soft tube section 31 is formed so that the distance (inter-wire gap) between adjacent wire members in the front-to-rear direction is wider than that of the second hard tube section 32. As a result, the bending rigidity of the second soft tube section 31 is smaller than that of the second hard tube section 32, making it easier to flex flexibly to follow the bending of the blood vessel. In the illustrated example, adjacent wire members in the front-to-rear direction in the second hard tube section 32 abut against each other. In other words, the second hard tube section 32 is formed as a tightly wound coil spring. As a result, in the intermediate section 15a of the second flexible tube 15, the second hard tube section 32 is easier to flex flexibly to follow the bending deformation of the second soft tube section 31.

[0030] A front portion of the second soft tube section 31 is joined or bonded to the front fixing member 25. As a result, the front end of the second flexible tubular body 15 is fixed to the front end portions of the first flexible tubular body 11 and the operating wire 12 via the front fixing member 25. The rear portion of the second soft tube section 31 is located between the front fixing member 25 and the intermediate fixing member 23. The intermediate fixing member 23 is joined or bonded to the outer circumferential surface of a portion of the second hard tube section 32 located between the front end portion located inside the first flexible tubular body 11 and the rear end portion located inside the support body 14. As a result, the rear portion of the second flexible tubular body 15 located rearward of the front end portion is fixed to the support body 14 and the rear end portion of the first flexible tubular body 11 via the intermediate fixing member 23. In the illustrated example, the intermediate fixing member 23 does not close the inside of the second hard tube section 32, and the inside of the support body 14 is in communication with the rear portion of the second soft tube section 31 through the inside of the second hard tube section 32.

[0031] The intermediate section 15a of the second flexible tubular body 15, located between the front fixing member 25 and the middle fixing member 23, is composed of the rear section of the second soft tubular section 31 and the front end section of the second hard tubular section 32. As a result, the bending rigidity of the intermediate section 15a of the second flexible tubular body 15 decreases stepwise from the rear to the front. Alternatively, the bending rigidity of the intermediate section 15a of the second flexible tubular body 15 may decrease linearly from the rear to the front. In the illustrated example, the length in the front-rear direction of the rear section of the second soft tubular section 31 is longer than the length in the front-rear direction of the front end section of the second hard tubular section 32. Alternatively, the length of the former may be shorter than the length of the latter. Within the intermediate section 11a of the first flexible tubular body 11, the rear section of the second soft tubular section 31 straddles the boundary between the first hard tubular section 22 and the first soft tubular section 21 located at the front of the pair of first soft tubular sections 21 in the front-rear direction.

[0032] The operation wire 12 is inserted inside the second flexible tubular body 15. The central axis O2 of the second flexible tubular body 15 and the front end 12a of the operation wire 12 are spaced apart in one radial direction from the central axis O1 of the first flexible tubular body 11. The front end 12a of the operation wire 12 is fixed to the front end of the second flexible tubular body 15 by, for example, soldering, brazing, adhesive bonding, or crimping, while being spaced apart in one radial direction from the central axis O2 of the second flexible tubular body 15. The operation wire 12 is disposed on the inner circumferential surface of the second flexible tubular body 15.

[0033] The outer peripheral surface of the front portion of the support 14 and the outer peripheral surface of a portion of the medical wire 1 located forward of the front portion of the support 14 are coated with a hydrophilic material. This allows the medical wire 1 to be moved smoothly through blood vessels with less snagging. The outer peripheral surface of the portion of the medical wire 1 located rearward of the front portion of the support 14 is coated with a hydrophobic material. This makes it less likely for the hand operating the medical wire 1 to slip. The outer peripheral surface of the operating portion 13 does not need to be coated with a hydrophobic material. Examples of hydrophilic materials include polyvinylpyrrolidone, maleic acid-based resins, and hyaluronic acid-based resins. Examples of hydrophobic materials include fluorine-based resins (PTFE, PFA, etc.), silicone-based resins, etc.

[0034] In this embodiment, a locking protrusion 12b is formed on the front end 12a of the operation wire 12, protruding radially from a portion of the operation wire 12 located between the front end 12a and the rear end. The entire front end 12a of the operation wire 12, including the locking protrusion 12b, is embedded in the front fixing member 25. The locking protrusion 12b is formed into a plate shape by pressing the front end 12a of the operation wire 12 in the radial direction. The rear portion of the locking protrusion 12b protrudes from the front of the second flexible tubular body 15 into the front end of the second flexible tubular body 15, and its width along one radial direction increases toward the front. The rear portion of the locking protrusion 12b abuts or is close to the front-to-rear opening edge of the second flexible tubular body 15. The front portion of the locking protrusion 12b extends forward from the front-to-rear opening edge of the second flexible tubular body 15. The width of the front portion of the locking projection 12b along one radial direction is the same over the entire length in the front-rear direction.

[0035] As shown in FIG. 1B , the locking protrusion 12b may be a bulging portion that bulges out in the radial direction at the front end 12a of the operation wire 12. In the illustrated example, the locking protrusion 12b is formed in a spherical shape. The rear portion of the locking protrusion 12b protrudes from the front of the second flexible tubular body 15 into the front end of the second flexible tubular body 15 and abuts or is close to the front-to-rear opening edge of the second flexible tubular body 15. The front portion of the locking protrusion 12b protrudes forward from the front-to-rear opening edge of the second flexible tubular body 15. As shown in FIG. 1C , the locking protrusion 12b may be formed in a loop shape by being wound around a portion of the wire constituting the front-to-rear opening edge of the second flexible tubular body 15 that is located at one end in the radial direction. The locking projection 12b is located at the same position in the radial direction as the outer circumferential surface of the front end portion of the first flexible tubular body 11, or at a position radially inward.

[0036] As described above, with the medical wire 1 according to this embodiment, the front end 12a of the manipulation wire 12 is fixed to the front end of the first flexible tubular body 11 in a state spaced apart in one radial direction from the central axis O1 of the first flexible tubular body 11. Therefore, when the manipulation wire 12 is pulled rearward relative to the support portion 14, the first flexible tubular body 11 is compressed and deformed while bending in one radial direction. This allows the physician to select a blood vessel at a vascular bifurcation and advance the medical wire 1 into the target blood vessel while bending the front end of the medical wire 1 in a desired direction by manipulating the manipulation wire 12. This reduces the physician's dependency on the sense of manipulation when guiding the medical wire 1 along the blood vessel to reach a chronic total occlusion lesion or the like, and also eliminates the need to insert and remove the medical wire from the blood vessel to fine-tune the curvature of the front end of the medical wire outside the body.

[0037] Furthermore, when the manipulation wire 12 is pulled rearward relative to the support portion 14, the front ends of the manipulation wire 12 and the first flexible tubular body 11 move rearward, and the first flexible tubular body 11 is compressed and deformed in the front-to-rear direction between the support portion 14, thereby increasing the bending rigidity of the first flexible tubular body 11. Therefore, by manipulating the manipulation wire 12 while the medical wire 1 is inserted into a blood vessel, the bending rigidity of the first flexible tubular body 11 can be changed.

[0038] As a result, when the medical wire 1 is to penetrate a chronic total occlusion lesion or the like, the bending rigidity of the first flexible tubular body 11 is kept low until the medical wire 1 is advanced into a blood vessel and reaches the chronic total occlusion lesion or the like within the blood vessel, and when the medical wire 1 is thrust into the chronic total occlusion lesion or the like and penetrates the chronic total occlusion lesion or the like with the medical wire 1, the manipulation wire 12 is pulled rearward relative to the support part 14 to increase the bending rigidity of the first flexible tubular body 11, and after penetrating the chronic total occlusion lesion or the like, the manipulation of the manipulation wire 12 can be released to return the bending rigidity of the first flexible tubular body 11 to its original low state. This eliminates the need to use different medical wires with different bending rigidities by inserting and removing them from the blood vessel or the like to penetrate a chronic total occlusion lesion or the like.

[0039] As a result, the operation time can be reduced.

[0040] The front end 12a of the operation wire 12 is embedded in a front fixing member 25 that closes the front end opening of the first flexible tubular body 11, and a locking protrusion 12b is formed on the front end 12a of the operation wire 12, protruding radially from a portion of the operation wire 12 that is located between the front end 12a and the rear end. Therefore, the locking protrusion 12b is caught on the front fixing member 25 in the front-rear direction, and it is possible to prevent the front end 12a of the operation wire 12 from coming off the front fixing member 25 when the operation wire 12 is operated.

[0041] Because the second flexible tubular body 15 is provided, when the manipulation wire 12 is pulled rearward relative to the support portion 14, the first flexible tubular body 11 and the second flexible tubular body 15 are bent in one radial direction while being compressed and deformed. Therefore, for example, while maintaining the outer diameter of the medical wire 1, it is possible to easily adjust (design) the relationship between the manipulation force on the manipulation wire 12 and the bending shape of the front end portion of the medical wire 1.

[0042] Next, a medical wire 2 according to a second embodiment of the present invention will be described with reference to Fig. 2. In this second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and their description will be omitted, with only the differences being described.

[0043] In the medical wire 2 of this embodiment, a protruding portion 16 that is engaged with the first flexible tubular body 11 and straddles the front end opening edge of the first flexible tubular body 11 in the radial direction is provided at the front end 12a of the operation wire 12, which is spaced apart in one radial direction from the central axis O1 of the first flexible tubular body 11. In the example shown in the figure, the protruding portion 16 straddles in the radial direction a portion of the wire that constitutes the front end opening edge of the first flexible tubular body 11, which is located at the end in one radial direction. The protruding portion 16 straddles the front end opening edges of both the first flexible tubular body 11 and the second flexible tubular body 15 in one radial direction.

[0044] The protruding portion 16 includes a folded portion 16a and a swiveling portion 16b, and is embedded in the front fixing member 25. The folded portion 16a extends rearward from the front end portion 12a of the operating wire 12 in one radial direction and straddles the front end opening edges of the first flexible tubular body 11 and the second flexible tubular body 15 in one radial direction. The swiveling portion 16b is provided in the space (gap) between adjacent wire rods in the front-rear direction at the front end portion (first soft tubular section 21) of the first flexible tubular body 11, and extends rearward from the folded portion 16a while swiveling around the central axis O1. The swiveling portion 16b is provided in the space (gap) between adjacent wire rods in the front-rear direction at the front end portion of the first flexible tubular body 11, in contact with or adjacent to these wire rods in the front-rear direction. The swiveling portion 16b swivels around the central axis O1 multiple times. The outer diameter of the swirling portion 16 b is equal to the outer diameter of the front end portion of the first flexible tubular body 11 .

[0045] As described above, the medical wire 2 according to this embodiment also has the same effects as the medical wire 1 shown in Fig. 1A. Furthermore, the front end 12a of the operation wire 12 is embedded in the front fixing member 25 that closes the front end opening of the first flexible tubular body 11, and the front end 12a of the operation wire 12 is provided with a protruding portion 16 that radially straddles the edge of the front end opening of the first flexible tubular body 11 and is engaged with the first flexible tubular body 11. Therefore, the protruding portion 16 is caught on the first flexible tubular body 11 in the front-rear direction, and the front end 12a of the operation wire 12 can be prevented from coming off the front fixing member 25 when the operation wire 12 is operated.

[0046] The protruding portion 16 is provided in the space (gap) between adjacent wire rods in the front-rear direction at the front end of the first flexible tubular body 11, and includes a swivel portion 16b that extends in the front-rear direction while swiveling around the central axis O1. This makes it possible to reliably lock the protruding portion 16 to the first flexible tubular body 11, and also makes it possible to keep the outer diameter of the front end of the medical wire 2 small.

[0047] The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0048] For example, the bending rigidity of the intermediate portions 11a, 15a may be the same over the entire length in the front-rear direction.

[0049] In addition, it is possible to replace the components in the above-described embodiments with well-known components as appropriate, without departing from the spirit of the present invention, and the above-described embodiments and variations may be combined as appropriate.

[0050] REFERENCE SIGNS LIST 1, 2 Medical wire 11 First flexible tubular body 12 Operating wire 12a Front end portion of operating wire 12b Locking protrusion 14 Support body 15 Second flexible tubular body 16 Protruding portion 25 Front fixing member (fixing member) O1 Central axis of first flexible tubular body O2 Central axis of second flexible tubular body

Claims

1. A medical wire comprising: a first flexible tube body extending in the front-rear direction and formed to be bendable; an operation wire extending in the front-rear direction and inserted inside the first flexible tube body; and a support fixed to the rear end portion of the first flexible tube body, wherein a front end portion of the operation wire is fixed to a front end portion of the first flexible tube body while being separated from a central axis of the first flexible tube body in one direction in the radial direction, a front end opening of the first flexible tube body is closed by a fixing member, the front end portion of the operation wire is embedded in the fixing member, and a locking protrusion protruding in the radial direction is formed at the front end portion of the operation wire at a position between the front end portion and the rear end portion of the operation wire.

2. A medical wire comprising: a first flexible tube body extending in the front-rear direction and formed to be bendable; an operation wire extending in the front-rear direction and inserted inside the first flexible tube body; and a support fixed to the rear end portion of the first flexible tube body, wherein a front end portion of the operation wire is fixed to a front end portion of the first flexible tube body while being separated from a central axis of the first flexible tube body in one direction in the radial direction, a front end opening of the first flexible tube body is closed by a fixing member, the front end portion of the operation wire is embedded in the fixing member, and a protruding portion is provided at the front end portion of the operation wire, which straddles a front end opening edge of the first flexible tube body in the radial direction and is locked to the first flexible tube body.

3. The medical wire according to claim 1 or 2, wherein a second flexible tube body extending in the front-rear direction and formed to be bendable is inserted inside the first flexible tube body, the operation wire is inserted inside the second flexible tube body, a central axis of the second flexible tube body and a front end portion of the operation wire are separated from a central axis of the first flexible tube body in one direction in the radial direction, a front end portion of the second flexible tube body is fixed to at least one of front end portions of the first flexible tube body and the operation wire, and a rear portion of the second flexible tube body located rearward of the front end portion is fixed to at least one of the support and a rear end portion of the first flexible tube body.

Citation Information

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