Medical wire

Abstract

A medical wire (1) is provided with a first flexible tubular body (11), a support body (14), and an operation wire (12). A front end part of the operation wire is fixed to a front end part of the first flexible tubular body while being separated in one direction (X) radially from the center axis (O1) of the first flexible tubular body. Of the medical wire, a portion positioned forward of a rear end part (11b) of the first flexible tubular body is defined as a flexible region (L1) which can be bent and deformed in association with the operation of the operation wire, and a portion positioned rearward of the flexible region is defined as a rigid region (L2) having a higher bending rigidity than that of the flexible region. Of the operation wire, a flexible portion (17) positioned in the flexible region is provided with at least a first region (18) and a second region (19) which is provided so as to differ in position in the front-rear direction from the first region, and which has a higher bending rigidity than that of the first region in one direction or in another direction opposite to the one direction.

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. 2024-117616, filed on July 23, 2024, the contents of which are incorporated herein by reference.

[0002] A known medical wire configuration includes a first flexible tubular body extending in the front-rear direction and formed to be bendable, a cylindrical support body extending rearward from the rear end of the first flexible tubular body and fixed to the rear end of the first flexible tubular body, and a manipulation wire extending in the front-rear direction and inserted integrally inside the first flexible tubular body and the support body, the front end of the manipulation wire being fixed to the front end of the first flexible tubular body while being spaced apart from the central axis of the first flexible tubular body in one of the radial directions, as shown in Patent Document 1. With this medical wire, when the medical wire is inserted into a blood vessel, the manipulation wire can be manipulated to bend the front end of the medical wire, thereby selecting a blood vessel at a blood vessel branch and allowing the medical wire to enter the target blood vessel, and the bending rigidity of the first flexible tubular body can also be changed.

[0003] Japanese Patent No. 7415071

[0004] However, with conventional medical wires, it may not be possible to bend the medical wire into a desired shape by simply manipulating the manipulation wire.

[0005] The present invention provides a medical wire that can be bent into a desired shape when the operating wire is operated.

[0006] A medical wire according to one aspect of the present invention is a medical wire including: a first flexible tubular body extending in a front-rear direction and formed to be bendable; a cylindrical support body extending rearward from a rear end of the first flexible tubular body and fixed to the rear end of the first flexible tubular body; and a manipulation wire extending in the front-rear direction and inserted integrally inside the first flexible tubular body and the support body, wherein a front end of the manipulation wire is fixed to the front end of the first flexible tubular body in a state spaced apart from a central axis of the first flexible tubular body in one of radial directions. The medical wire has a portion located forward of the rear end of the first flexible tubular body that is a flexible region that can be bent and deformed in response to manipulation of the manipulation wire, and a portion located rearward of the flexible region that is a rigid region that has higher bending rigidity than the flexible region. The flexible portion of the manipulation wire that is located in the flexible region includes at least a first region and a second region that is located at a different position in the front-to-rear direction from the first region and has higher bending rigidity than the first region in the one direction or in another direction opposite to the one direction.

[0007] The flexible portion of the manipulation wire located in the flexible region includes at least a first region and a second region that are positioned at different positions in the front-to-rear direction, so that when the manipulation wire is manipulated, the manipulation wire can be bent and deformed such that the region of the manipulation wire located forward of the boundary between the first and second regions is displaced in the one direction or the other direction starting from the boundary between the first and second regions. Thus, by adjusting the front-to-rear position of the boundary between the first and second regions in the flexible portion of the manipulation wire when designing the medical wire, it is possible to obtain a medical wire that can be bent into a desired shape when the manipulation wire is manipulated.

[0008] The bending rigidity of the first region in the other direction may be lower than the bending rigidity of the second region in the other direction, and the bending rigidity of a rigid portion of the operating wire located in the rigid region may be greater than or equal to the bending rigidity of the second region in the other direction.

[0009] Because the bending rigidity of the rigid portion of the operation wire located in the rigid region is equal to or greater than the bending rigidity of the second region of the flexible portion in the other direction, when the rear end of the operation wire is pushed forward, it is possible to suppress buckling deformation of the rigid portion of the operation wire, and to displace the flexible portion of the operation wire forward. As a result, when the operation wire is pushed forward, the end of the first flexible tubing in one direction is pulled forward by the flexible portion of the operation wire, thereby bending the first flexible tubing in the other direction. Conversely, when the operation wire is pulled rearward, the front ends of the operation wire and the first flexible tubing move rearward, and the first flexible tubing is compressed and deformed in the front-to-rear direction between the front end of the first flexible tubing to which the operation wire is fixed and the support, thereby increasing the bending rigidity of the first flexible tubing. As described above, bending the first flexible tubing and increasing the bending rigidity of the first flexible tubing can achieve different operation of the operation wire, and the bending deformation and bending rigidity of the first flexible tubing can be easily adjusted.

[0010] The second region may be located rearward of the first region, may be formed integrally with the rigid portion using the same material, and may be connected to the rigid portion without any steps in the front-rear direction.

[0011] Since the second region is formed integrally with the rigid portion using the same material and is connected to the rigid portion without any steps in the front-to-back direction, the entire portion of the operating wire located behind the first region, which has low bending rigidity, is less likely to bend or deform when the operating wire is operated, making it easier to bend or deform the first region into the desired shape with high precision, thereby improving operability.

[0012] The operating wire may be integrally formed from the same material over its entire length, and the outer diameter of the first region may be smaller than the outer diameter of the second region.

[0013] Since the operating wire is integrally formed from the same material over its entire length and the outer diameter of the first region is smaller than the outer diameter of the second region, the operating wire can be easily formed with durability compared to, for example, a case where the first region and the second region are formed from different materials and joined together.

[0014] According to the above aspect of the present invention, the medical wire can be bent into a desired shape when the manipulation wire is manipulated.

[0015] 1 is a longitudinal cross-sectional view of a medical wire according to an embodiment.

[0016] An embodiment of the medical wire will be described below with reference to Fig. 1. 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 second flexible tubular body 15 and the operating section 13 may not be provided.

[0017] 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.

[0018] 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 coil is wound around a central axis O1. The size of the first flexible tubular body 11 in the front-rear direction is, for example, 10 mm. The outer diameter of the first flexible tubular body 11 is large enough to be inserted into a blood vessel (for example, 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.

[0019] 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.

[0020] The support body 14 extends rearward from the rear end 11b of the first flexible tubular body 11 and is fixed to the rear end 11b of the first flexible tubular body 11. The support body 14 may be 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 11b of the first flexible tubular body 11 are fixed to each other by, for example, soldering, brazing, adhesive, or crimping. In the illustrated example, a cylindrical intermediate fixing member 23 made of, for example, a solder material, 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.

[0021] 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.

[0022] The operation unit 13 is provided rearward of the support body 14. The operation unit 13 protrudes rearward from the support body 14. The operation unit 13 is provided 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.

[0023] The operation wire 12 extends in the front-rear direction and is inserted integrally inside the first flexible tubular body 11 and the support body 14. The operation wire 12 is formed to be elastically deformable. The front end of the operation wire 12 is fixed to the front end of the first flexible tubular body 11 by, for example, soldering, brazing, adhesive bonding, or crimping, in a state spaced apart from the central axis O1 in one radial direction X. The rear end of the operation wire 12 is located rearward of the support body 14. Note that a plurality of operation wires 12 may be provided at intervals in the circumferential direction.

[0024] The operation wire 12 extends straight in the front-rear direction over almost the entire length. The size of the operation wire 12 in the front-rear direction is determined depending on the size of the patient's body and may be, for example, 2000 mm to 3000 mm. Note that the operation wire 12 may extend in the front-rear direction while bending, for example. Alternatively, only the front end of the operation wire 12 may be spaced apart from the central axis O1 in one radial direction X, and the portion of the operation wire 12 located rearward of the front end may be disposed coaxially with the central axis O1, for example.

[0025] In the illustrated example, the front end opening of the first flexible tubular body 11 is closed by a front fixing member 25 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 of the operation wire 12 is embedded in the front fixing member 25.

[0026] 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 illustrated example, 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 having lower bending rigidity than the first hard tubular section 22 and sandwiching the first hard tubular section 22 in the front-to-rear direction. Of the pair of first soft tubular sections 21, the first soft tubular section 21 located on the front side has a size of, for example, 1 mm 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.

[0027] The first soft tube section 21 is formed so that the distance (inter-wire gap) between adjacent wires 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, and the first soft tube section 21 located in the intermediate section 11a of the first flexible tubular body 11 is easily bent flexibly to follow the bending of the blood vessel. The inter-wire gap in the first soft tube section 21 is, for example, 0.04 mm. In the illustrated example, adjacent wires in the first hard tube section 22 in the front-to-rear direction 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 tubular body 11, the first hard tube section 22 is easily bent flexibly to follow the bending deformation of the first soft tube section 21.

[0028] Of the pair of first soft tube sections 21, the front end of the first soft tube section 21 located on the front side is joined or adhered to the front fixing member 25, and the rear portion of this first soft tube section 21 located rearward of the front end 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 and constitutes the rear end portion 11b of the first flexible tube body 11. Therefore, of the pair of first soft tube sections 21, the intermediate portion 11a located between the front fixing member 25 and the intermediate fixing member 23 is constituted by 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 portion 11a of the first flexible tube body 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.

[0029] 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 11b 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.

[0030] 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 coil of the second flexible tubular body 15 is wound around the central axis O2. 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.

[0031] The bending rigidity of the intermediate section 15a of the second flexible tubular body 15, 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 illustrated example, the second flexible tubular body 15 is configured by connecting a second soft tubular section 31, which has low bending rigidity, and a second hard tubular section 32, which has higher bending rigidity than the second soft tubular section 31, in this order from the front to the rear. The second soft tubular section 31 protrudes forward from the first flexible tubular body 11, and the second hard tubular section 32 protrudes rearward from the first flexible tubular body 11. The length of the second soft tubular section 31 in the front-to-rear direction is shorter than the length of the second hard tubular section 32 in the front-to-rear direction.

[0032] The second soft tube section 31 is formed so that the distance (inter-wire gap) between adjacent wires 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, and the second soft tube section 31 located in the intermediate section 15a of the second flexible tubular body 15 is easily bent flexibly to follow the bending of the blood vessel. In the illustrated example, adjacent wires in the second hard tube section 32 in the front-to-rear direction abut against each other. In other words, the second hard tube section 32 is formed as a tightly wound coil spring. As a result, the second hard tube section 32 in the intermediate section 15a of the second flexible tubular body 15 is easily bent flexibly to follow the bending deformation of the second soft tube section 31.

[0033] The front end 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 ends of the first flexible tubular body 11 and the operating wire 12 via the front fixing member 25. A rear portion of the second soft tube section 31, which is located rearward of the front end, 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 peripheral surface of a portion of the second hard tube section 32 that is located within the rear end portion 11b of the first flexible tubular body 11 and within the support body 14. As a result, the rear end of the second flexible tubular body 15 is fixed to the support body 14 and the rear end portion 11b 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 inside of the rear portion of the second soft tube section 31 through the inside of the second hard tube section 32.

[0034] The intermediate section 15a of the second flexible tubular body 15, which is located between the front fixing member 25 and the middle fixing member 23, is composed of a rear section located rearward of the front end of the second soft tubular section 31 and a front section located forward of the rear end 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. Note that the bending rigidity of the intermediate section 15a of the second flexible tubular body 15 may also decrease linearly from the rear to the front. In the illustrated example, the length in the front-to-rear direction of the rear section of the second soft tubular section 31 is shorter than the length in the front-to-rear direction of the front section of the second hard tubular section 32. Note that the length of the former may be equal to or greater than the length of the latter. The rear part of the second soft tube section 31 straddles the boundary between the first hard tube section 22 and the first soft tube section 21 located at the front of the pair of first soft tube sections 21 within the intermediate section 11a of the first flexible tube body 11 in the front-to-rear direction.

[0035] 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 of the operation wire 12 are spaced apart in one radial direction X from the central axis O1 of the first flexible tubular body 11. The front end of the operation wire 12 is fixed to the front end of the second flexible tubular body 15 by, for example, soldering, brazing, bonding, or crimping, in a state spaced apart in one radial direction X from the central axis O2 of the second flexible tubular body 15. The operation wire 12 is disposed on the end of the inner circumferential surface of the second flexible tubular body 15 in the one radial direction X.

[0036] Of the front end portion of the operation wire 12, a protruding portion 12a protruding forward from the first flexible tubular body 11 and the second flexible tubular body 15 is bent in one direction X and engaged with the edge of the front end opening of the second flexible tubular body 15. The protruding portion 12a of the operation wire 12 is located at the same radial position as the outer circumferential surface of the front end portion of the first flexible tubular body 11 or is located radially inward with respect to the outer circumferential surface of the front end portion of the first flexible tubular body 11. The protruding portion 12a of the operation wire 12 is bent in one direction X and then folded back rearward, so that the distal end surface of the operation wire 12 faces rearward. The distal end surface of the operation wire 12 abuts against or is close to the edge of the front end opening of the first flexible tubular body 11. Note that the distal end surface of the operation wire 12 may face radially. The protruding portion 12a of the operation wire 12 may be bent in another direction Y opposite to the one direction X. Regardless of the direction in which the protruding portion 12a of the operation wire 12 is bent, when the operation wire 12 is pushed forward, the intermediate portions 11a and 15a of the first flexible tubular body 11 and the second flexible tubular body 15 are bent in the other direction Y, respectively.

[0037] In order to move the medical wire 1 smoothly within a blood vessel with less snagging, the outer surface of the medical wire 1 may be coated with a hydrophilic or hydrophobic material. Examples of hydrophilic materials include polyvinylpyrrolidone, maleic acid-based resins, and hyaluronic acid-based resins, while examples of hydrophobic materials include fluorine-based resins (PTFE, PFA, etc.), silicone-based resins, etc.

[0038] In the medical wire 1, a portion located forward of the rear end 11b of the first flexible tubular body 11 is a flexible region L1 that can be bent and deformed in response to manipulation of the manipulation wire 12, and a portion located rearward of the flexible region L1 is a rigid region L2 that has higher bending rigidity than the flexible region L1. Note that the rigid region L2 may be formed to be bendable or non-bendable.

[0039] In the present embodiment, the flexible portion 17 of the operation wire 12 located in the flexible region L1 includes at least a first region 18 having low bending rigidity in one direction X or in the other direction Y opposite to the one direction X, and a second region 19 located at a different position in the front-rear direction from the first region 18 and having higher bending rigidity in the one direction X or the other direction Y than the first region 18. The flexible portion 17 is formed to be bendably deformable in the one direction X or the other direction Y. In the illustrated example, the bending rigidity of the first region 18 in the one direction X and the other direction Y is lower than the bending rigidity of the second region 19 in the one direction X and the other direction Y. Note that the bending rigidity of the first region 18 may be lower than the bending rigidity of the second region 19 only in the other direction Y of the radial direction. The bending rigidity of the rigid portion 20 of the operation wire 12 located in the rigid region L2 is equal to or greater than the bending rigidity of the second region 19 in the other direction Y. The rigid portion 20 may be formed to be bendable or non-bendable.

[0040] In the illustrated example, the flexible portion 17 includes one first region 18 and one second region 19. The flexible portion 17 may include a plurality of first regions 18 and a plurality of second regions 19, or the number of first regions 18 and the number of second regions 19 may differ from each other. The flexible portion 17 may also include another region having a bending rigidity different from that of the first region 18 and the second region 19. The second region 19 is located rearward of the first region 18. The second region 19 is formed integrally with the rigid portion 20 using the same material and is connected to the rigid portion 20 without any step in the front-to-rear direction. This makes the bending rigidity of the second region 19 and the rigid portion 20 the same. The bending rigidity of the rigid portion 20 may be smaller than that of the second region 19.

[0041] The operation wire 12 is integrally formed into a rod shape using the same material over its entire length. The operation wire 12 is formed into a solid rod shape. The outer diameter of the first region 18 is smaller than the outer diameter of the second region 19. The outer diameters of the first region 18 and the second region 19 are the same over their entire lengths in the front-to-rear direction.

[0042] The first region 18 (hereinafter referred to as the straight portion) excluding the protruding portion 12a, and the second region 19 each extend straight in the front-rear direction. The straight portion of the first region 18 and the second region 19 are arranged coaxially with a common axis (not shown) extending in the front-rear direction. A boundary 26 between the first region 18 and the second region 19 is formed in a stepped shape facing forward. The boundary 26 decreases in diameter toward the front. The boundary 26 is located at the rear end of the flexible region L1 of the medical wire 1. The first region 18 straddles, in the front-rear direction, the boundary between the first hard tube portion 22 and the first soft tube portion 21 located on the front side of the pair of first soft tube portions 21, as well as the boundary between the second soft tube portion 31 and the second hard tube portion 32.

[0043] As described above, according to the medical wire 1 of this embodiment, the flexible portion 17 of the manipulation wire 12 located in the flexible region L1 includes at least the first region 18 and the second region 19 located at different positions in the front-to-rear direction, so that when the manipulation wire 12 is manipulated, the manipulation wire 12 can be bent and deformed such that the first region 18 of the manipulation wire 12 located in front of the boundary region 26 between the first region 18 and the second region 19 is displaced in one direction X or the other direction Y, starting from the boundary region 26 between the first region 18 and the second region 19. Thus, by adjusting the position of the boundary region 26 between the first region 18 and the second region 19 in the front-to-rear direction in the flexible portion 17 of the manipulation wire 12 when the medical wire 1 is designed, it is possible to obtain a medical wire 1 that can be bent into a desired shape when the manipulation wire 12 is manipulated.

[0044] Because the bending rigidity of the rigid portion 20 of the operation wire 12 located in the rigid region L2 is equal to or greater than the bending rigidity in the other direction Y of the second region 19 of the flexible portion 17, when the rear end of the operation wire 12 is pushed forward, it is possible to suppress buckling deformation of the rigid portion 20 of the operation wire 12, and to displace the flexible portion 17 of the operation wire 12 forward. As a result, when the operation wire 12 is pushed forward, the end of the first flexible tubular body 11 in the one direction X is pulled forward by the flexible portion 17 of the operation wire 12, and the first flexible tubular body 11 can be bent in the other direction Y. Conversely, when the operation wire 12 is pulled rearward, the front end portions of the operation 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 front end of the first flexible tubular body 11 to which the operation wire 12 is fixed and the support body 14, thereby increasing the bending rigidity of the first flexible tubular body 11. As described above, it is possible to operate the operating wire 12 differently by bending the first flexible tubular body 11 and by increasing the bending rigidity of the first flexible tubular body 11, and the bending deformation and bending rigidity of the first flexible tubular body 11 can be easily adjusted.

[0045] In the illustrated example, when the rear end of the manipulation wire 12 is pushed forward, the boundary portion 26 comes into contact with the inner circumferential surface of the second flexible tubular body 15 in one direction X, and this portion becomes a bending portion, causing the flexible region L1 of the medical wire 1 to bend in the other direction Y. Note that when the rear end of the manipulation wire 12 is pushed forward, the flexible region L1 may be bent in the other direction Y without the boundary portion 26 coming into contact with the inner circumferential surface of the second flexible tubular body 15.

[0046] Since the second region 19 is formed integrally with the rigid portion 20 using the same material and is connected to the rigid portion 20 without any steps in the front-to-rear direction, the entire portion of the operating wire 12 located behind the first region 18, which has low bending rigidity, is less likely to bend or deform when the operating wire 12 is operated, making it easier to bend or deform the first region 18 into a desired shape with high precision, thereby improving operability.

[0047] Since the operating wire 12 is integrally formed from the same material over its entire length and the outer diameter of the first region 18 is smaller than the outer diameter of the second region 19, the operating wire 12 can be easily formed with durability compared to, for example, a case where the first region 18 and the second region 19 are formed from different materials and joined together.

[0048] 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.

[0049] For example, the medical wire 1 may be operated by pulling the manipulation wire 12 backward. In this case, in the process of pulling the manipulation wire 12 backward, first, the first flexible tubular body 11 is bent in the direction X while undergoing compressive deformation in the front-rear direction, and then the first flexible tubular body 11 is compressively deformed in the front-rear direction between the support body 14 and the front end of the first flexible tubular body 11 to which the manipulation wire 12 is fixed, so that the first flexible tubular body 11 gradually straightens in the front-rear direction and the bending rigidity of the first flexible tubular body 11 increases. In this process, when the first flexible tubular body 11 is bent in the direction X, the manipulation wire 12 is bent and deformed starting from the boundary 26 between the first region 18 and the second region 19 such that the first region 18 of the manipulation wire 12 located forward of the boundary 26 is displaced in the direction X. For example, when operating the medical wire 1, if the operating wire 12 is simply pulled backward without the rear end of the operating wire 12 being pushed forward, the bending rigidity of the first region 18 may be lower than the bending rigidity of the second region 19 only in one radial direction X.

[0050] The boundary portion 26 may be a flat surface facing forward. The position of the boundary portion 26 in the flexible region L1 in the front-rear direction may be changed as appropriate. For example, the boundary portion 26 may be located inside the second soft tube portion 31. The flexible portion 17 of the operation wire 12 may not have the boundary portion 26, and may have an outer diameter that linearly decreases from the rear to the front. The operation wire 12 may be formed in a hollow rod shape (tube shape). The central axes of the straight portion of the first region 18 and the second region 19 may not coincide with each other. For example, the central axis of the straight portion of the first region 18 may be located closer to the one direction X than the central axis of the second region 19. In this configuration, the ends of the straight portion of the first region 18 and the second region 19 on the outer circumferential surfaces in the one direction X may be continuous without any steps in the front-rear direction.

[0051] The flexible portion 17 of the operation wire 12 may have a configuration in which the first region 18 and the second region 19 are formed of different materials and joined together. The flexible portion 17 of the operation wire 12 may have a configuration in which a material made of the same material and formed with the same outer diameter over the entire length in the front-to-rear direction is used, and a portion of this material in the front-to-rear direction is formed into a plate shape with the front and back surfaces facing one direction X and the other direction Y to provide the first region 18, and the portion of this material excluding the first region 18 is used as the second region 19. The flexible portion 17 of the operation wire 12 may have a configuration in which a material made of the same material and formed with the same outer diameter over the entire length in the front-to-rear direction is used, and a D-cut portion is formed in a portion of this material in the front-to-rear direction to provide the first region 18, and the portion of this material excluding the first region 18 is used as the second region 19. The flexible portion 17 of the operation wire 12 may be made of a material that is made of the same material and has the same outer diameter over the entire length in the front-to-rear direction, and a plurality of grooves extending around the entire circumference of the material may be formed in a series in the front-to-rear direction in a portion of the material in the front-to-rear direction to provide the first region 18, with the remaining portion of the material excluding the first region 18 being the second region 19. The grooves may be screw grooves that extend helically. The flexible portion 17 of the operation wire 12 may be made of a material that is made of the same material and has the same outer diameter over the entire length in the front-to-rear direction, and a portion of the material in the front-to-rear direction may be annealed to soften the entire circumference, to provide the first region 18, with the remaining portion of the material excluding the first region 18 being the second region 19. The flexible portion 17 of the operating wire 12 may be made of a material that is made of the same material and has the same outer diameter over the entire length in the front-to-rear direction, and holes, slits, etc. that open in one direction X or the other direction Y may be formed on the outer peripheral surface of a portion of the material in the front-to-rear direction to provide a first region 18, with the portion of the material excluding the first region 18 being made into a second region 19.

[0052] In the operation wire 12, the second region 19 may be provided at a different position in the front-rear direction from the first region 18 and may have a higher bending rigidity than the first region 18. In the operation wire 12, the bending rigidity of the rigid portion 20 may be equal to or greater than the bending rigidity of the second region 19.

[0053] 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.

[0054] 1 Medical wire 11 First flexible tubular body 11b Rear end portion 12 Operating wire 14 Support body 17 Flexible portion 18 First region 19 Second region 20 Rigid portion L1 Flexible region L2 Rigid region O1 Central axis of first flexible tubular body X One direction Y Other direction

Claims

1. A medical wire comprising: a first flexible tubular body extending in the front-rear direction and formed to be bendable; a cylindrical support body extending rearward from the rear end of the first flexible tubular body and fixed to the rear end of the first flexible tubular body; and a manipulation wire extending in the front-rear direction and inserted integrally inside the first flexible tubular body and the support 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, and a portion of the medical wire located forward of the rear end of the first flexible tubular body is a flexible region that can be bent in response to manipulation of the manipulation wire, and a portion located rearward of the flexible region is a rigid region having higher bending rigidity than the flexible region, and the flexible portion of the manipulation wire located in the flexible region comprises a first region and a second region that is provided at a different position in the front-to-rear direction from the first region and has higher bending rigidity than the first region in the one direction or in another direction opposite to the one direction.

2. The medical wire according to claim 1, wherein the bending rigidity in the other direction of the first region is lower than the bending rigidity in the other direction of the second region, and the bending rigidity of the rigid portion of the operating wire located in the rigid region is equal to or greater than the bending rigidity in the other direction of the second region.

3. The medical wire according to claim 2, wherein the second region is located rearward of the first region, and the second region is integrally formed with the rigid portion using the same material, and is connected to the rigid portion without any steps in the front-to-rear direction.

4. A medical wire according to any one of claims 1 to 3, wherein the operating wire is integrally formed from the same material over its entire length, and the outer diameter of the first region is smaller than the outer diameter of the second region.

Images