Medical wire

Abstract

Disclosed is a medical wire (1) comprising a first flexible tube (11), a support (14), and an operation wire (12), wherein the front end of the operation wire is fixed to the front end of the first flexible tube in a state of being eccentric with respect to the central axis (O1) of the first flexible tube or in a state of intersecting the central axis of the first flexible tube, the operation wire includes at least a first region (18) and a second region (19) which is positioned differently from the first region in the front-rear direction and has higher bending rigidity than the first region, and at least the front end of the support is inserted into and fixed inside the rear end of the first flexible tube.

Description

Medical wire

[0001] The present invention relates to medical wires such as guide wires. This application claims priority based on Japanese Patent Application No. 2025-006857 filed in Japan on January 17, 2025, and the content thereof is incorporated herein by reference.

[0002] Conventionally, as a medical wire, for example, as shown in Patent Document 1 below, a first flexible tubular body that extends in the front-rear direction and is formed to be bendable, and a rear end portion of the first flexible tubular body that extends rearward and is fixed to the rear end portion of the first flexible tubular body. A cylindrical support body, an operation wire that extends in the front-rear direction and is integrally inserted inside each of the first flexible tubular body and the support body, and a front end portion of the operation wire is eccentric in one direction in the radial direction from the central axis of the first flexible tubular body. A configuration fixed to the front end portion of the first flexible tubular body is known. In this medical wire, with the medical wire inserted into the blood vessel, the operation wire is operated to bend the front end portion of the medical wire while selecting the blood vessel at the blood vessel branch portion and causing the medical wire to enter the target blood vessel. At the same time, the bending rigidity of the first flexible tubular body can also be changed.

[0003] Japanese Patent No. 7415071

[0004] However, in the conventional medical wire, it is conceivable that the medical wire cannot be smoothly bent into a desired shape only by operating the operation wire.

[0005] The present invention provides a medical wire that can smoothly bend a medical wire into a desired shape when operating an operation wire.

[0006] A medical wire according to one aspect of the present invention comprises: a first flexible tube extending in the front-rear direction and formed to be bendable; a cylindrical support extending rearward from the rear end of the first flexible tube and fixed to the rear end of the first flexible tube; and an operating wire extending in the front-rear direction and integrally inserted inside the first flexible tube and the support, respectively, wherein the front end of the operating wire is fixed to the front end of the first flexible tube in a state eccentric with respect to the central axis of the first flexible tube or in a state intersecting the central axis of the first flexible tube; the operating wire comprises at least a first region and a second region provided at a different position from the first region in the front-rear direction and having higher bending rigidity than the first region; and at least the front end of the support is inserted and fixed inside the rear end of the first flexible tube.

[0007] The front end of the operating wire is fixed to the front end of the first flexible tube in a state that is eccentric with respect to the central axis of the first flexible tube, or in a state that intersects with respect to the central axis of the first flexible tube. Furthermore, since the operating wire has at least a first region and a second region that are positioned differently in the front-rear direction, when the operating wire is operated, the operating wire can be bent and deformed so that the region of the operating wire located in front of the boundary between the first region and the second region is displaced, starting from the boundary between the first region and the second region. This makes it possible to obtain a medical wire that can be smoothly bent into a desired shape when the operating wire is operated by adjusting the front-rear position of the boundary between the first region and the second region in the operating wire during the design of the medical wire. Since at least the front end of the support is inserted into and fixed inside the rear end of the first flexible tube, the radial relative position of the support and the first flexible tube can be accurately determined during the manufacture of the medical wire, and the support and the first flexible tube can be strongly joined to each other.

[0008] Of the medical wire, at least the portion located forward of the rear end of the first flexible tube is a flexible region that can be bent and deformed in accordance with the operation of the operating wire, and the portion located backward of the flexible region is a rigid region with higher bending rigidity than the flexible region, the first region is located forward of the second region, at least a part of the first region is located in the flexible region, and the bending rigidity of the 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.

[0009] In this design, the bending stiffness of the rigid portion of the operating wire located in the rigid region is greater than or equal to the bending stiffness of the second region located behind the first region. Therefore, when the rear end of the operating wire is pushed forward, it is possible to suppress buckling deformation of the rigid portion of the operating wire, and the front end of the operating wire can be displaced forward. In this case, the front end of the operating wire is fixed to the front end of the first flexible tube in a state that is eccentric with respect to the central axis of the first flexible tube, or in a state that intersects with the central axis of the first flexible tube. As a result, when the operating wire is pushed forward, a part of the circumferential direction of the first flexible tube is pulled forward by the front end of the operating wire, thereby bending the first flexible tube. Conversely, when the operating wire is pulled backward, the front ends of both the operating wire and the first flexible tube move backward, and the first flexible tube undergoes compressive deformation in the front-rear direction between itself and the support, thereby increasing the bending stiffness of the first flexible tube. As described above, it becomes possible to operate the control wire differently depending on whether the first flexible tube is bent or the bending rigidity of the first flexible tube is increased, and the bending deformation and bending rigidity of the first flexible tube can be easily adjusted.

[0010] According to the above embodiment of the present invention, when operating the operating wire, the medical wire can be smoothly bent into a desired shape.

[0011] This is a longitudinal cross-sectional view of a medical wire according to one embodiment.

[0012] An embodiment of a medical wire will be described below with reference to Figure 1. The medical wire 1 is a guide wire comprising a first flexible tube 11, an operating wire 12, an operating section 13, a support 14, and a second flexible tube 15. The first flexible tube 11, the operating wire 12, the operating section 13, the support 14, and the second flexible tube 15 are formed of, for example, a metal material. The materials forming the first flexible tube 11, the operating wire 12, the operating section 13, the support 14, and the second flexible tube 15 may be changed as appropriate. The second flexible tube 15 and the operating section 13 are optional.

[0013] The operating section 13 and the support body 14 are formed in a cylindrical shape and are arranged coaxially with the central axis O1 of the first flexible tube body 11. Hereinafter, the side on which the first flexible tube body 11 is located relative to the support body 14 in the direction in which the central axis O1 extends will be called the front side, the side on which the operating section 13 is located relative to the support body 14 in the direction in which the central axis O1 extends will be called the rear side, and the direction in which the central axis O1 extends will be called the front-rear direction. The direction that intersects the central axis O1 when viewed from the front-rear direction will be called the radial direction, and the direction that circles around the central axis O1 when viewed from the front-rear direction will be called the circumferential direction.

[0014] The first flexible tube 11 extends in the front-rear direction and is formed to be bendable. The first flexible tube 11 is a coil spring that extends in the front-rear direction. The size of the first flexible tube 11 in the front-rear direction is, for example, 10 mm. The outer diameter of the first flexible tube 11 is large enough to be inserted into a blood vessel (for example, 0.2 mm or more and 1.0 mm or less). The external shape and size of the first flexible tube 11 as viewed from the front-rear direction are the same along its entire length in the front-rear direction. The diameter of the wire forming the first flexible tube 11 is the same along its entire length.

[0015] Furthermore, the diameter of the wire forming the first flexible tube 11 does not have to be the same along its entire length, and the external shape and size of the first flexible tube 11 as viewed from the front-to-back direction do not have to be the same along its entire length in the front-to-back direction. For example, the outer diameter of the first flexible tube 11 may decrease as it approaches the front. The first flexible tube 11 is not limited to a coil spring, but may also be, for example, a tube or the like with a circumferential wall that extends continuously along its entire length in both the front-to-back and circumferential directions.

[0016] The support 14 extends rearward from the rear end 11b of the first flexible tube 11 and is fixed to the rear end 11b of the first flexible tube 11. The support 14 may be formed to be bendable. The front end of the support 14 and the rear end 11b of the first flexible tube 11 are fixed together, for example, by soldering, brazing, bonding, or crimping. In the illustrated example, a cylindrical internal fixing member 23 made of, for example, solder material, brazing material, or adhesive extends forward from the front end of the support 14. The outer circumferential surface of the internal fixing member 23 is flush with the outer circumferential surface of the first flexible tube 11.

[0017] The outer diameter of the support 14 is equal to the inner diameter of the first flexible tube 11, and is sized to be insertable into a blood vessel (for example, 0.2 mm to 1.0 mm). The external shape and size of the support 14 as viewed from the front-to-back direction are the same along its entire length in the front-to-back direction. However, the external shape and size of the support 14 as viewed from the front-to-back direction do not necessarily have to be the same along its entire length in the front-to-back direction. For example, the outer diameter of the support 14 may decrease towards the front.

[0018] Here, of the medical wire 1, at least the portion located forward of the rear end 11b of the first flexible tube 11 is a flexible region L1 that can be bent and deformed in accordance with the operation of the operating wire 12, and the portion located backward of the flexible region L1 is a rigid region L2 that has higher bending rigidity than the flexible region L1. The rigid region L2 may be formed to be bendable or to be non-bendable. In the illustrated example, of the medical wire 1, the portion located forward of the front end opening edge of the support 14 is a flexible region L1 that can be bent and deformed in accordance with the operation of the operating wire 12. The flexible region L1 may be limited to the portion of the medical wire 1 located forward of the rear end 11b of the first flexible tube 11.

[0019] The operating section 13 is located behind the support 14. The operating section 13 protrudes rearward from the support 14. The operating section 13 is provided so as to be movable in the front-rear direction relative to the support 14. In the illustrated example, the rear end of the support 14 is inserted into the front part of the operating section 13. The front opening edge of the operating section 13 and the rear opening edge of the support 14 may face each other in the front-rear direction, or the front part of the operating section 13 may be inserted into the rear end of the support 14. The rear end of the operating wire 12 is fixed to the operating section 13 by, for example, soldering, brazing, bonding, or crimping. In the illustrated example, the rear opening of the operating section 13 is closed by a rear fixing member 24 made of, for example, solder, brazing material, or adhesive, and the rear end of the operating wire 12 is embedded in the rear fixing member 24.

[0020] The operating wire 12 extends in the front-rear direction and is integrally inserted inside the first flexible tube 11 and the support 14, respectively. The operating wire 12 is formed to be elastically deformable. The rear end of the operating wire 12 is located behind the support 14. Multiple operating wires 12 may be provided at intervals in the circumferential direction.

[0021] The length of the operating wire 12 in the anterior-posterior direction is determined according to the size of the patient's body, and may be, for example, 2000 mm or more and 3000 mm or less. The operating wire 12 may extend in the anterior-posterior direction while bending, for example, and the portion of the operating wire 12 located behind the front end may be arranged coaxially with the central axis O1, for example.

[0022] The front end of the operating wire 12 is fixed to the front end of the first flexible tube body 11 by, for example, soldering, brazing, bonding, or crimping, in a state where it is eccentric in one radial direction X with respect to the central axis O1, or, when viewed from the left or right direction perpendicular to one radial direction X, it extends from a position displaced in one radial direction X with respect to the central axis O1 toward the front end surface of the operating wire 12 toward the other radial direction Y opposite to direction X, and intersects with respect to the central axis O1.

[0023] In the illustrated example, the front end of the operating wire 12 is eccentric in one direction X with respect to the central axis O1. The central axis of the operating wire 12 is offset from the central axis O1 in one radial direction X along its entire length in the front-rear direction. The front end opening of the first flexible tube 11 is closed by a front fixing member 25 made of, for example, solder, brazing material, or adhesive. The outer circumferential surface of the front fixing member 25 is connected to the outer circumferential surface of the first flexible tube 11 without any step in the front-rear direction. The front end of the operating wire 12 is embedded in the front fixing member 25.

[0024] Furthermore, if the front end of the operating wire 12 is positioned such that, when viewed from the left and right directions, it extends in the other direction Y from a position displaced in one direction X with respect to the central axis O1 as it approaches the front end surface of the operating wire 12, and intersects with the central axis O1, then the left and right positions of the front end of the operating wire 12 and the central axis O1 of the first flexible tube 11 may coincide with each other, or the front end of the operating wire 12 may be moved away from the central axis O1 of the first flexible tube 11 in the left and right directions.

[0025] The operating wire 12 comprises at least a first region 18 and a second region 19, which is positioned differently from the first region 18 in the front-rear direction and has higher bending rigidity than the first region 18. In this embodiment, the bending rigidity in one radial direction X, or in the other radial direction Y opposite to direction X, is higher in the second region 19 than in the first region 18.

[0026] The first region 18 is located in front of the second region 19, and at least a portion of the first region 18 is located in the flexible region L1. The bending stiffness of the first region 18 in the other direction Y is lower than the bending stiffness of the second region 19 in the other direction Y. In the illustrated example, the first region 18 is located in the flexible region L1 along its entire length in the front-rear direction. The second region 19 is located in the rigid region L2 along its entire length in the front-rear direction. The bending stiffness of the first region 18 in one direction X and the other direction Y is lower than the bending stiffness of the second region 19 in one direction X and the other direction Y. Note that, in the other direction Y of the radial direction, the bending stiffness of the first region 18 may be lower than the bending stiffness of the second region 19.

[0027] The bending stiffness of the rigid portion 20 of the operating wire 12 located in the rigid region L2 is greater than or equal to the bending stiffness of the second region 19 in the other direction Y. The rigid portion 20 may be formed to bend deformably or to be formed to be unable to bend deformably.

[0028] Here, the operating wire 12 is provided with a third region 33 that is positioned differently from the first region 18 and the second region 19 in the front-rear direction, and has higher bending rigidity in one direction X or the other direction Y than the first region 18 and the second region 19. The third region 33 is located behind the second region 19 and is located in the rigid region L2 along its entire length in the front-rear direction. The third region 33 and the second region 19 are located along the entire length in the front-rear direction within the rigid region L2. That is, the third region 33 and the second region 19 constitute the rigid portion 20 of the operating wire 12. The bending rigidity in one direction X and the other direction Y of the third region 33 is higher than the bending rigidity in one direction X and the other direction Y of the second region 19. Note that the operating wire 12 does not necessarily have to have the third region 33.

[0029] The operating wire 12 is formed as a single rod from the same material along its entire length. The operating wire 12 is formed as a solid rod. Of the first region 18, the second region 19, and the third region 33, the outer diameter of the first region 18 is the smallest, the outer diameter of the third region 33 is the largest, the length of the second region 19 in the front-to-back direction is the shortest, and the length of the third region 33 in the front-to-back direction is the longest.

[0030] The first boundary portion 26 between the first region 18 and the second region 19, and the second boundary portion 34 between the second region 19 and the third region 33, are each formed in a stepped shape facing forward. The first boundary portion 26 and the second boundary portion 34 decrease in diameter as they extend forward. The first boundary portion 26 is located in the same front-rear direction as the front end opening edge of the support 14, which is the boundary portion between the flexible region L1 and the rigid region L2. The second boundary portion 34 is located in the rigid region L2.

[0031] Here, the bending rigidity of the intermediate portion 11a of the first flexible tube body 11, located between the front end (front fixing member 25) and the rear end (middle fixing member 23), decreases as it moves from the rear to the front. In the illustrated example, the first flexible tube body 11 comprises a first rigid tube portion 22 with high bending rigidity, and a pair of first soft tube portions 21 that have lower bending rigidity than the first rigid tube portion 22 and sandwich the first rigid tube portion 22 in the front-rear direction. Of the pair of first soft tube portions 21, the front-rear dimension of the first soft tube portion 21 located on the front side is, for example, 1 mm.

[0032] The first soft tube section 21 is formed such that the spacing between adjacent wires in the front-rear direction (inter-wire gap) 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 middle section 11a of the first flexible tube body 11, is able to bend flexibly to follow the curved blood vessels. 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 front-rear direction of the first hard tube section 22 are in contact with each other. In other words, the first hard tube section 22 is a tightly wound coil spring. As a result, in the middle section 11a of the first flexible tube body 11, the first hard tube section 22 is able to bend flexibly to follow the bending deformation of the first soft tube section 21.

[0033] Of the pair of first flexible tube sections 21, the front end of the first flexible tube section 21 located at the front is joined or bonded to the front fixing member 25, and the rear part of this first flexible tube section 21, located behind the front end, is positioned between the front fixing member 25 and the middle fixing member 23. Of the pair of first flexible tube sections 21, the first flexible tube section 21 located at the rear is joined or bonded to the middle fixing member 23 over its entire length and constitutes the rear end 11b of the first flexible tube body 11. Therefore, the intermediate section 11a of the first flexible tube body 11, located between the front fixing member 25 and the middle fixing member 23, is composed of the entire first rigid tube section 22 and the rear part of the first flexible tube section 21 located at the front of the pair of first flexible tube sections 21. As a result, the bending rigidity of the intermediate section 11a of the first flexible tube body 11 decreases in stages from rear to front. Furthermore, the bending rigidity of the intermediate portion 11a of the first flexible tube body 11 may decrease linearly from the rear to the front. In the illustrated example, the length of the first rigid tube portion 22 in the front-rear direction is longer than the respective lengths of the pair of first soft tube portions 21 in the front-rear direction. However, the length of the former may be less than or equal to the length of the latter.

[0034] Here, at least the front end of the support 14 is inserted and fixed inside the rear end 11b of the first flexible tube 11. The front end of the support 14 is inserted inside the rear end of the first flexible tube portion 21, which is located at the rear of the pair of first flexible tube portions 21 in the first flexible tube 11, and the front end of this first flexible tube portion 21 protrudes forward from the support 14. The rear end of the intermediate fixing member 23 is disposed on the outer circumferential surface of the front end of the support 14, joining the rear end 11b of the first flexible tube 11 to the outer circumferential surface of the front end of the support 14.

[0035] The second flexible tube 15 extends in the front-rear direction and is formed to be bendable. The second flexible tube 15 is inserted inside the first flexible tube 11. The front end of the second flexible tube 15 is fixed to at least one of the front ends of the first flexible tube 11 and the operating wire 12, and the rear part of the second flexible tube 15, located behind the front end, is fixed to at least one of the support 14 and the rear end 11b of the first flexible tube 11. The front end of the second flexible tube 15 protrudes forward from the first flexible tube 11. Note that the second flexible tube 15 does not necessarily have to protrude in the front-rear direction from the first flexible tube 11.

[0036] At least one of the first flexible tube 11 and the second flexible tube 15 is a coil spring extending in the front-rear direction. In the illustrated example, both the first flexible tube 11 and the second flexible tube 15 are coil springs extending in the front-rear direction. The winding directions of the first flexible tube 11 and the second flexible tube 15 are opposite to each other. However, the winding directions of the first flexible tube 11 and the second flexible tube 15 may be the same. Either the first flexible tube 11 or the second flexible tube 15 is not limited to a coil spring, but may be, for example, a tube with a circumferential wall that extends continuously over its entire length in both the front-rear and circumferential directions.

[0037] In the second flexible tube body 15, the bending rigidity of the intermediate portion 15a located between the front end (front fixing member 25) and the rear end (middle fixing member 23) decreases as it moves from the rear to the front. In the illustrated example, the second flexible tube body 15 is composed of a second soft tube portion 31 with low bending rigidity and a second hard tube portion 32 with higher bending rigidity than the second soft tube portion 31, connected in this order from front to rear. The second soft tube portion 31 protrudes forward from the first flexible tube body 11. The length of the second soft tube portion 31 in the front-rear direction is shorter than the length of the second hard tube portion 32 in the front-rear direction.

[0038] The second soft tube section 31 is formed such that the spacing between adjacent wires in the front-to-back direction (inter-wire gap) 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 middle section 15a of the second flexible tube body 15, is able to bend flexibly to follow the curved blood vessels. In the illustrated example, adjacent wires in the front-to-back direction of the second hard tube section 32 are in contact with each other. In other words, the second hard tube section 32 is made up of a tightly wound coil spring. As a result, in the middle section 15a of the second flexible tube body 15, the second hard tube section 32 is able to bend flexibly to follow the bending deformation of the second soft tube section 31.

[0039] The front end of the second flexible tube section 31 is joined or bonded to the front fixing member 25. As a result, the front end of the second flexible tube body 15 is fixed to the front ends of the first flexible tube body 11 and the operating wire 12 via the front fixing member 25. The rear portion of the second flexible tube section 31, located behind the front end, is positioned between the front fixing member 25 and the middle fixing member 23. The middle fixing member 23 is joined or bonded to the outer circumferential surface of the rear end of the second rigid tube section 32, which is located inside the rear end 11b of the first flexible tube body 11 and inside the support 14. As a result, the rear end of the second flexible tube body 15 is fixed to the support 14 and the rear end 11b of the first flexible tube body 11 via the middle fixing member 23. In the illustrated example, the middle fixing member 23 does not block the inside of the second rigid tube section 32, and the inside of the support 14 communicates with the rear portion of the second flexible tube section 31 through the inside of the second rigid tube section 32.

[0040] The intermediate portion 15a of the second flexible tube 15, located between the front fixing member 25 and the middle fixing member 23, is composed of a rear portion of the second soft tube portion 31 located behind the front end and a front portion of the second rigid tube portion 32 located in front of the rear end. As a result, the bending rigidity of the intermediate portion 15a of the second flexible tube 15 decreases in stages from rear to front. Alternatively, the bending rigidity of the intermediate portion 15a of the second flexible tube 15 may decrease linearly from rear to front. In the illustrated example, the length of the rear portion of the second soft tube portion 31 in the front-rear direction is shorter than the length of the front portion of the second rigid tube portion 32 in the front-rear direction. Alternatively, the length of the former may be greater than or equal to the length of the latter. The rear portion of the second soft pipe section 31 straddles the boundary between the first rigid pipe section 22 and the first soft pipe section 21, which is located on the front side of the pair of first soft pipe sections 21, within the intermediate portion 11a of the first flexible pipe body 11, in the front-to-back direction.

[0041] An operating wire 12 is inserted inside the second flexible tube 15. The central axis of the second flexible tube 15 and the central axis of the front end of the operating wire 12 are separated from the central axis O1 of the first flexible tube 11 in one radial direction X. The central axis of the front end of the operating wire 12 is separated from the central axis of the second flexible tube 15 in one radial direction X. The operating wire 12 is in contact with or close to the end in one direction X on the inner circumferential surface of the second flexible tube 15. The first region 18 of the operating wire 12 straddles the boundary between the first rigid tube portion 22 and the first flexible tube portion 21 located on the front side of the pair of first flexible tube portions 21, and the boundary between the second flexible tube portion 31 and the second rigid tube portion 32, in the front-rear direction.

[0042] Of the front end portion of the operating wire 12, the protruding portion 12a that extends forward from the first flexible tube 11 and the second flexible tube 15 is bent in one direction X and locked to the front end opening edge of the second flexible tube 15. The protruding portion 12a of the operating wire 12 is located at the same radial position or radially inward with respect to the outer circumferential surface of the front end portion of the first flexible tube 11. As the protruding portion 12a of the operating wire 12 is bent in one direction X, it is folded back to the rear, and the front end surface of the operating wire 12 faces rearward. The front end surface of the operating wire 12 is in contact with or close to the front end opening edge of the first flexible tube 11.

[0043] Incidentally, the front end face of the operating wire 12 may face in the radial direction. The protruding portion 12a of the operating wire 12 is bent in the other direction Y opposite to the one direction X, and the front end portion of the operating wire 12, when viewed from the left-right direction, extends from a position displaced in the one direction X with respect to the central axis O1 toward the other direction Y as it approaches the front end face of the operating wire 12, and may be fixed to the front end portion of the first flexible tube body 11 in a state of intersecting the central axis O1. Regardless of the direction in which the protruding portion 12a of the operating wire 12 is bent, when the operating wire 12 is pushed forward, the intermediate portions 11a and 15a of the first flexible tube body 11 and the second flexible tube body 15 respectively bend in the other direction Y.

[0044] In order to move the medical wire 1 smoothly in the blood vessel with less snagging, the outer peripheral surface of the medical wire 1 may be coated with a hydrophilic material or a hydrophobic material. Examples of the hydrophilic material include, for example, polyvinylpyrrolidone, maleic acid-based resin, hyaluronic acid-based resin, etc., and examples of the hydrophobic material include, for example, fluorine-based resins (PTFE, PFA, etc.), silicone-based resins, etc.

[0045] As described above, according to the medical wire 1 of this embodiment, the front end of the operating wire 12 is fixed to the front end of the first flexible tube 11 in a state where it is eccentric in one direction X with respect to the central axis O1 of the first flexible tube 11, or, when viewed from the left and right directions, extends in the other direction Y from a position displaced in one direction X with respect to the central axis O1 as it approaches the front end surface of the operating wire 12, and intersects with respect to the central axis O1 of the first flexible tube 11. The operating wire 12 also comprises at least a first region 18 and a second region 19 which are provided at different positions in the front-rear direction. Therefore, when the operating wire 12 is operated, the operating wire 12 can be bent and deformed so that the first region 18, which is located in front of the first boundary 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 first boundary 26 between the first region 18 and the second region 19. As a result, when designing the medical wire 1, by adjusting the front-to-back position of the first boundary portion 26 in the operating wire 12, it is possible to obtain a medical wire 1 that can be smoothly bent into a desired shape when the operating wire 12 is operated.

[0046] Since at least the front end of the support 14 is inserted into and fixed inside the rear end 11b of the first flexible tube 11, the radial relative positions of the support 14 and the first flexible tube 11 can be accurately determined during the manufacture of the medical wire 1, and the support 14 and the first flexible tube 11 can be strongly joined to each other.

[0047] Among the operating wires 12, the bending rigidity of the rigid portion 20 located in the rigid region L2 is not less than the bending rigidity in the other direction Y of the second region 19 located behind the first region 18. Therefore, when the rear end portion of the operating wire 12 is pushed forward, it becomes possible to suppress the buckling deformation of the rigid portion 20 of the operating wire 12, and the front end portion of the operating wire 12 can be displaced forward. At this time, as described above, the front end portion of the operating wire 12 is fixed to the front end portion of the first flexible tube 11 in a state eccentric with respect to the central axis O1 of the first flexible tube 11 or in a state intersecting the central axis O1 of the first flexible tube 11. Therefore, when the operating wire 12 is pushed forward, by pulling the end portion (a part in the circumferential direction) in one direction X of the first flexible tube 11 forward by the front end portion of the operating wire 12, the first flexible tube 11 can be bent in the other direction Y. Conversely, when the operating wire 12 is pulled backward, the front end portions of the operating wire 12 and the first flexible tube 11 move backward, and the first flexible tube 11 is compressed and deformed in the front-rear direction with the support body 14, so that the bending rigidity of the first flexible tube 11 increases. From the above, it becomes possible to make the operations of the operating wire 12 different between bending the first flexible tube 11 and increasing the bending rigidity of the first flexible tube 11, and the bending deformation and bending rigidity of the first flexible tube 11 can be easily adjusted.

[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 operating wire 12 backward. In this case, during the process of pulling the operating wire 12 backward, first the first flexible tube 11 is compressed and deformed in the front-rear direction and bent in one direction X, and then the first flexible tube 11 is compressed and deformed in the front-rear direction between itself and the support 14, so that the first flexible tube 11 gradually becomes straight in the front-rear direction and the bending rigidity of the first flexible tube 11 increases. During this process, when the first flexible tube 11 bends in one direction X, the operating wire 12 bends and deforms so that the first region 18 located in front of the first boundary 26 between the first region 18 and the second region 19 is displaced in one direction X, starting from the first boundary 26 between the first region 18 and the second region 19. For example, when operating the medical wire 1, if the operating wire 12 is only pulled backward and the rear end of the operating wire 12 is not pushed forward, the bending rigidity of the first region 18 may be lower than that of the second region 19, but only in one radial direction X.

[0050] The first boundary portion 26 and the second boundary portion 34 may be planes facing forward. The positions of the first boundary portion 26 and the second boundary portion 34 in the front-rear direction may be changed as appropriate. For example, the first boundary portion 26 and the second boundary portion 34 may be located in the flexible region L1 or in the rigid region L2. The operating wire 12 may not have the first boundary portion 26 and the second boundary portion 34, and may have a configuration in which the outer diameter decreases linearly from rear to front. The operating wire 12 may be formed in the shape of a hollow rod (tube). The central axes of the first region 18 and the second region 19 do not have to coincide with each other. For example, the central axis of the first region 18 may be located closer to the X direction than the central axis of the second region 19. In this configuration, the ends in the X direction on the outer circumferential surfaces of the first region 18 and the second region 19 may be connected without steps in the front-rear direction.

[0051] The operating wire 12 may be configured such that the first region 18 and the second region 19 are formed from different materials and joined together. Alternatively, the operating wire 12 may be configured such that the operating wire 12 is made of a material formed from the same material with the same outer diameter along its entire length in the front-to-back direction, and the first region 18 is provided by forming a plate-like shape in a part of this material in the front-to-back direction with its front and back surfaces facing one direction X and the other direction Y, and the part of this material excluding the first region 18 is designated as the second region 19. Alternatively, the operating wire 12 may be made of a material formed from the same material with the same outer diameter along its entire length in the front-to-back direction, and the first region 18 is provided by forming a D-cut portion (a portion with a D-shaped cross-section in the radial direction) in a part of this material in the front-to-back direction, and the part of this material excluding the first region 18 is designated as the second region 19. As the operating wire 12, a material formed with the same outer diameter and material across its entire length in the front-to-back direction may be used. A first region 18 may be provided by forming multiple grooves extending around the entire circumference in a part of this material in the front-to-back direction, and the portion of this material excluding the first region 18 may be designated as the second region 19. These grooves may be spirally extending screw grooves. As the operating wire 12, a material formed with the same outer diameter and material across its entire length in the front-to-back direction may be used. A first region 18 may be provided by annealing a part of this material around the entire circumference in the front-to-back direction to soften this part, and the portion of this material excluding the first region 18 may be designated as the second region 19. As the operating wire 12, a material formed with the same outer diameter and material across its entire length in the front-to-back direction may be used. A first region 18 may be provided by forming holes, slits, etc., opening in one direction X or the other direction Y on the outer circumferential surface of a part of this material in the front-to-back direction, and the portion of this material excluding the first region 18 may be designated as the second region 19.

[0052] The front ends of the first flexible tube 11 and the operating wire 12 may each be provided with tip members fixed via front fixing members 25. The tip members may have a receiving surface that supports the front end of the operating wire 12 in a state where it is eccentric in one direction X with respect to the central axis O1 of the first flexible tube 11, or, when viewed from the left and right directions, extends in the other direction Y from a position displaced in one direction X with respect to the central axis O1 as it approaches the front end surface of the operating wire 12, and intersects with the central axis O1 of the first flexible tube 11.

[0053] Furthermore, without departing from the spirit of the present invention, the components in the above embodiments may be replaced with well-known components as appropriate, and the above embodiments and modifications may be combined as appropriate.

[0054] 1 Medical wire 11 First flexible tubular body 11b Rear end portion 12 Operating wire 14 Support body 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 tube extending in the front-rear direction and formed to be bendable; a cylindrical support extending rearward from the rear end of the first flexible tube and fixed to the rear end of the first flexible tube; and an operating wire extending in the front-rear direction and integrally inserted inside the first flexible tube and the support, wherein the front end of the operating wire is fixed to the front end of the first flexible tube in a state eccentric with respect to the central axis of the first flexible tube, or in a state intersecting the central axis of the first flexible tube; the operating wire comprises at least a first region and a second region provided at a different position from the first region in the front-rear direction and having higher bending rigidity than the first region; and at least the front end of the support is inserted and fixed inside the rear end of the first flexible tube.

2. The medical wire according to claim 1, wherein at least the portion of the medical wire located forward of the rear end of the first flexible tube is a flexible region that can be bent and deformed in accordance with the operation of the operating wire, and the portion located backward of the flexible region is a rigid region with higher bending rigidity than the flexible region, the first region is located forward of the second region, at least a part of the first region is located in the flexible 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 of the second region.

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