Medical wire
The medical wire design with varying rigidity regions and eccentric support allows for precise bending, addressing the challenge of shaping conventional wires, enhancing navigation and assembly.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- NHK SPRING CO LTD
- Filing Date
- 2026-01-14
- Publication Date
- 2026-07-23
Smart Images
Figure JP2026000789_23072026_PF_FP_ABST
Abstract
Description
Medical wire
[0001] The present invention relates to a medical wire such as a guide wire. This application claims priority based on Japanese Patent Application No. 2025-006862 filed in Japan on January 17, 2025, and the contents thereof are 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. And 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 the front end portion of the operation wire is radially offset from the central axis of the first flexible tubular body. A configuration fixed to the front end portion of the first flexible tubular body in one direction is known. In this medical wire, in a state where the medical wire is inserted into a blood vessel, the operation wire is operated to bend the front end portion of the medical wire while selecting a blood vessel at a blood vessel branch portion and allowing 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 a 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; an operating wire extending in the front-rear direction and integrally inserted inside the first flexible tube and the support, respectively; and a tip member to which the front ends of the first flexible tube and the operating wire are fixed, wherein the tip member has a receiving surface that supports the front end of the operating wire 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, and 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.
[0007] The front end of the operating wire is supported on the receiving surface of the tip member in a state that is eccentric with respect to the central axis of the first flexible tube, or intersects with respect to the central axis of the first flexible tube, and the operating wire has at least a first region and a second region that are positioned differently in the front-rear direction. Therefore, 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. As a result, when designing a medical wire, by adjusting the front-rear position of the boundary between the first region and the second region in the operating wire, it is possible to obtain a medical wire that can be smoothly bent into a desired shape when the operating wire is operated. The tip member has a receiving surface formed thereon that supports the front end of the operating wire. Therefore, when manufacturing a medical wire, if the front end of the operating wire inserted inside the first flexible tube is brought into contact with the receiving surface of a tip member that has been pre-fixed to the front end of the first flexible tube, the front end of the operating wire slides along the receiving surface, making it possible to accurately set the front end of the operating wire in a state that is eccentric with respect to the central axis of the first flexible tube, or in a state that is intersecting with the central axis of the first flexible tube. This improves ease of assembly and ensures that a medical wire can be reliably obtained that can be smoothly bent into the desired shape when the operating wire is operated.
[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] 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. At this time, the front end of the operating wire is supported on the receiving surface in a state that is eccentric with respect to the central axis of the first flexible tube, or intersecting 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] At least the front end of the support has a plurality of circumferentially extending slits formed at intervals in the front-rear direction, and at least the portion of the medical wire located in front of the rear end of the first flexible tube, and at least the portion of the support where the front end is located, may be a flexible region that can be bent and deformed in conjunction with the operation of the operating wire.
[0011] At least the front end of the support is formed to have multiple slits and bend deformably in conjunction with the operation of the operating wire, and the flexible region includes at least the portion of the medical wire located forward of the rear end of the first flexible tube, and at least the portion of the support where the front end is located. As a result, the length of the flexible region can be secured, and the bending stiffness at each position in the front-rear direction of the flexible region can be easily adjusted, making it possible to obtain a medical wire that can be smoothly bent into a desired shape when the operating wire is operated.
[0012] At least the front end of the support may be inserted into and fixed inside the rear end of the first flexible tube.
[0013] At least the front end of the support is inserted into and fixed inside the rear end of the first flexible tube. This allows for precise determination of the radial relative position of the support and the first flexible tube during the manufacturing of the medical wire, and enables a strong bond between the support and the first flexible tube.
[0014] The aforementioned chip member may be made of an X-ray opaque material.
[0015] The tip component is made of an X-ray opaque material. Therefore, for example, the tip component can be visualized when performing a procedure using a medical wire under X-ray fluoroscopy.
[0016] According to the above embodiment of the present invention, the medical wire can be smoothly bent into a desired shape when operating the operating wire.
[0017] This is a longitudinal cross-sectional view of the medical wire according to the first embodiment. This is a side view of the support in Figure 1. This is a longitudinal cross-sectional view of the medical wire according to the second embodiment. This is a longitudinal cross-sectional view of the medical wire according to the third embodiment. This is a longitudinal cross-sectional view of the medical wire according to the fourth embodiment.
[0018] The first embodiment of the medical wire will be described below with reference to Figures 1 and 2. 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, a second flexible tube 15, and a tip member 16. The first flexible tube 11, the operating wire 12, the operating section 13, the support 14, the second flexible tube 15, and the tip member 16 are formed of, for example, a metal material. The materials used to form the first flexible tube 11, the operating wire 12, the operating section 13, the support 14, the second flexible tube 15, and the tip member 16 may be changed as appropriate. The second flexible tube 15 and the operating section 13 may be omitted.
[0019] 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.
[0020] 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.
[0021] 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.
[0022] 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 rear end opening edge of the first flexible tube 11 abuts against the front end opening edge of the support 14 in the front-rear direction. 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 connected to the outer circumferential surfaces of the support 14 and the first flexible tube 11 without any steps in the front-rear direction.
[0023] The outer diameter of the support 14 is the same as the outer 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-rear direction are the same along its entire length in the front-rear direction. However, the external shape and size of the support 14 as viewed from the front-rear direction do not have to be the same along its entire length in the front-rear direction. For example, the outer diameter of the support 14 may decrease as it approaches the front. The external shapes and sizes of the support 14 and the first flexible tube 11 as viewed from the front-rear direction may be different from each other. In this case, it is preferable that, as viewed from the front-rear direction, the support 14 does not protrude radially outward from the outer circumferential surface of the first flexible tube 11.
[0024] 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, while 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.
[0025] In the illustrated example, the portion of the medical wire 1 where the rear end 11b of the first flexible tube 11 is located is also a flexible region L1 that can be bent and deformed in accordance with the operation of the operating wire 12. Of the support 14, at least the front end has a plurality of circumferentially extending slits S formed at intervals in the front-rear direction. Thus, of the medical wire 1, the portion located forward from the front end opening edge of the support 14, and at least the portion of the support 14 where the front end is located, are both flexible regions L1 that can be bent and deformed in accordance with the operation of the operating wire 12.
[0026] Slits S adjacent to each other in the front-to-back direction have different positions in the circumferential direction. In the illustrated example, slits S located in the support 14 are positioned in a portion displaced in one radial direction X with respect to the central axis O1, and slits S located in a portion displaced in the other radial direction Y opposite to the radial direction X with respect to the central axis O1, and these are alternately arranged at intervals in the front-to-back direction. The slits S penetrate the support 14 in the radial direction. The slits S are provided over an angular range of approximately 180° around the central axis O1. The slits S may also extend spirally around the central axis O1. Multiple slits S may be provided at the same position in the circumferential direction, or they may be provided at the same position in the front-to-back direction but separated in the circumferential direction.
[0027] 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.
[0028] 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. The operating wire 12 extends straight in the front-rear direction along its entire length. The length of the operating wire 12 in the front-rear 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 front-rear direction while bending, for example.
[0029] 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.
[0030] 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 and the second region 19 are each located in the flexible region L1 along their 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.
[0031] 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.
[0032] 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 spans the flexible region L1 and the rigid region L2. The third region 33 is located along the entire length in the front-rear direction of the rigid region L2. That is, the third region 33 constitutes 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.
[0033] 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. The first region 18, the second region 19, and the third region 33 are arranged coaxially. 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.
[0034] 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 and the second boundary portion 34 are located in the flexible region L1. The first boundary portion 26 is located in the same front-to-back direction as the rear end opening edge of the first flexible tube body 11 and the front end opening edge of the support body 14.
[0035] The front ends of the first flexible tube 11 and the operating wire 12 are fixed to the tip member 16 by, for example, soldering, brazing, bonding, crimping, or welding. The tip member 16 has a receiving surface 27 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 or right direction perpendicular to one radial direction X, the surface 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.
[0036] In the illustrated example, the tip member 16 comprises an insertion shaft 28 inserted into the first flexible tube 11 and a protruding shaft 29 projecting forward from the front end of the insertion shaft 28. The insertion shaft 28 and the protruding shaft 29 are formed in a cylindrical shape and are arranged coaxially with the central axis O1. The front end of the protruding shaft 29 is formed in a hemispherical shape that protrudes forward. The outer circumferential surfaces of the protruding shaft 29 and the front end of the first flexible tube 11 are located at equivalent radial positions to each other. When the insertion shaft 28 and the first flexible tube 11 are joined to each other 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 surfaces of the protruding shaft 29 and the front end of the first flexible tube 11 without any step in the front-rear direction.
[0037] The insertion shaft 28 and the projection shaft 29 have through holes that extend in the front-rear direction. In this embodiment, the central axis of the through hole is offset from the central axis O1 in one direction X. The front end of the operating wire 12 is inserted into the through hole. As a result, the inner circumferential surface of the through hole becomes a receiving surface 27 that supports the front end of the operating wire 12 in a state where it is eccentrically offset from the central axis O1 of the first flexible tube body 11 in one direction X. The front end surface of the operating wire 12 faces forward and is connected to the front end surface of the projection shaft 29 without any step difference. 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. Note that of the operating wire 12, only the central axis of the front end is offset from the central axis O1 in one radial direction X, and the portion located behind the front end may be arranged coaxially with the central axis O1, for example.
[0038] The tip member 16 is made of an X-ray opaque material. The tip member 16 is made of, for example, gold, platinum, iridium, tungsten, tantalum, nickel, or an alloy of two or more of these materials.
[0039] In the first flexible tube body 11, the bending rigidity of the intermediate portion 11a located between the front end (front fixing member 25) and the rear end (middle fixing member 23) 11b 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 size of the first soft tube portion 21 located on the front side is, for example, 1 mm. Of the pair of first soft tube portions 21, the number of turns of the front-side first soft tube portion 21 is greater than the number of turns of the rear-side first soft tube portion 21. The number of turns of the former may be less than or equal to the number of turns of the latter.
[0040] 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.
[0041] Of the pair of first flexible tube sections 21, the front portion of the first flexible tube section 21 located at the front is fixed to the tip member 16 via a front fixing member 25, and the rear portion of this first flexible tube section 21, located behind the front portion, is positioned between the front fixing member 25 and the middle fixing member 23. Of the pair of first flexible tube sections 21, the rear portion of the first flexible tube section 21 is joined or bonded to the middle fixing member 23 over its entire length and constitutes the rear end portion 11b of the first flexible tube body 11. Therefore, the intermediate portion 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 portion 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 portion 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 length of the rear portion of the first flexible tube portion 21, which is located on the front side of the pair of first flexible tube portions 21. However, the length of the former may be less than or equal to the length of the latter.
[0042] 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 the tip member 16 via a front fixing member 25, 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 via a middle fixing member 23. The front opening edge of the second flexible tube 15 abuts against the rear end surface of the insertion shaft 28 of the tip member 16. The rear end of the second flexible tube 15 protrudes rearward from the first flexible tube 11. The rear end of the second flexible tube 15 is inserted into the support 14. Note that the second flexible tube 15 does not necessarily have to protrude in the front-rear direction from the first flexible tube 11.
[0043] At least one of the first flexible tube body 11 and the second flexible tube body 15 is a coil spring extending in the front-rear direction. In the illustrated example, both the first flexible tube body 11 and the second flexible tube body 15 are coil springs. The winding directions of the first flexible tube body 11 and the second flexible tube body 15 are opposite to each other. Incidentally, the winding directions of the first flexible tube body 11 and the second flexible tube body 15 may be the same as each other. Either one of the first flexible tube body 11 and the second flexible tube body 15 is not limited to a coil spring, and may be, for example, a tube body composed of a peripheral wall continuously extending over the entire length in the front-rear direction and the circumferential direction, etc.
[0044] Among the second flexible tube body 15, the bending rigidity of the intermediate portion 15a located between the front end portion (front fixing member 25) and the rear end portion (middle fixing member 23) becomes lower as it goes from the rear to the front. In the illustrated example, the second flexible tube body 15 is configured by connecting, in this order from the front to the rear, a second soft tube portion 31 with a low bending rigidity and a second hard tube portion 32 with a higher bending rigidity than the second soft tube portion 31. The second hard tube portion 32 protrudes rearward 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.
[0045] The second soft tube portion 31 is formed such that the interval (wire gap) between wires adjacent to each other in the front-rear direction is wider than that of the second hard tube portion 32. Thereby, the bending rigidity of the second soft tube portion 31 is smaller than the bending rigidity of the second hard tube portion 32, and the second soft tube portion 31 located in the intermediate portion 15a of the second flexible tube body 15 is easily bent flexibly following the bent blood vessel. In the illustrated example, the wires adjacent to each other in the front-rear direction in the second hard tube portion 32 are in contact with each other. That is, the second hard tube portion 32 is a tightly wound coil spring. Thereby, in the intermediate portion 15a of the second flexible tube body 15, the second hard tube portion 32 is easily bent flexibly following the bending deformation of the second soft tube portion 31.
[0046] Among the second flexible tube portion 31, the front end portion is fixed to the chip member 16 via the front fixing member 25, and the rear portion located behind the front end portion is positioned between the front fixing member 25 and the middle fixing member 23. Among the second rigid tube portion 32, the middle fixing member 23 is joined or adhered to the outer peripheral surface of the rear portion located within the rear end portion 11b of the first flexible tube body 11 and within the support body 14. Thereby, the rear portion of the second flexible tube body 15 is fixed to the support body 14 and the rear end portion 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 portion 32, and the inside of the support body 14 communicates with the inside of the second rigid tube portion 32 and extends into the rear portion of the second flexible tube portion 31.
[0047] Among the second flexible tube body 15, the intermediate portion 15a located between the front fixing member 25 and the middle fixing member 23 is composed of the rear portion of the second flexible tube portion 31 located behind the front end portion and the front portion of the second rigid tube portion 32 located in front of the rear portion. Thereby, the bending rigidity of the intermediate portion 15a of the second flexible tube body 15 gradually decreases from the rear to the front. Note that the bending rigidity of the intermediate portion 15a of the second flexible tube body 15 may decrease linearly from the rear to the front. The rear portion of the second flexible tube portion 31 straddles the boundary portion between the first rigid tube portion 22 and the first flexible tube portion 21 located on the front side among the pair of first flexible tube portions 21 in the intermediate portion 11a of the first flexible tube body 11 in the front-rear direction.
[0048] The operation wire 12 is inserted inside the second flexible tube body 15. The central axis of the second flexible tube body 15 and the central axis of the front end portion of the operation wire 12 are separated from the central axis O1 of the first flexible tube body 11 in one direction X in the radial direction. The central axis of the front end portion of the operation wire 12 is separated from the central axis of the second flexible tube body 15 in one direction X in the radial direction. The operation wire 12 abuts or is close to the end portion in one direction X on the inner peripheral surface of the second flexible tube body 15. The first region 18 of the operation wire 12 straddles the boundary portion between the first rigid tube portion 22 and the first flexible tube portion 21 located on the front side among the pair of first flexible tube portions 21, and the boundary portion between the second flexible tube portion 31 and the second rigid tube portion 32 in the front-rear direction, respectively.
[0049] To allow the medical wire 1 to move smoothly within the blood vessel with minimal 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 fluoropolymer resins (PTFE, PFA, etc.) and silicone-based resins.
[0050] As described above, according to the medical wire 1 of this embodiment, the front end of the operating wire 12 is supported on the receiving surface 27 of the tip member 16 in a state eccentric in one direction X with respect to the central axis O1 of the first flexible tube body 11, and the operating wire 12 has 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 located in front of the first boundary 26 of the operating wire 12 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-rear position of the first boundary 26 of 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.
[0051] The tip member 16 has a receiving surface 27 that supports the front end of the operating wire 12. Therefore, when manufacturing the medical wire 1, if the front end of the operating wire 12 inserted inside the first flexible tube 11 is brought into contact with the receiving surface 27 of the tip member 16 which has been fixed to the front end of the first flexible tube 11 in advance, the front end of the operating wire 12 slides along the receiving surface 27, making it possible to accurately set the front end of the operating wire 12 in a state that is eccentric in one direction X with respect to the central axis O1 of the first flexible tube 11. This improves ease of assembly and ensures that a medical wire 1 can be reliably obtained that can be smoothly bent into the desired shape when the operating wire 12 is operated.
[0052] The bending rigidity of the rigid portion 20 of the operating wire 12 located in the rigid region L2 is greater than or equal to the bending rigidity in the other direction Y of the second region 19 located behind the first region 18. Therefore, when the rear end of the operating wire 12 is pushed forward, it is possible to suppress buckling deformation of the rigid portion 20 of the operating wire 12, and the front end of the operating wire 12 can be displaced forward. At this time, since the front end of the operating wire 12 is supported on the receiving surface 27 in a state eccentric in one direction X with respect to the central axis O1 of the first flexible pipe 11, when the operating wire 12 is pushed forward, the end of the first flexible pipe 11 in one direction X (a part in the circumferential direction) is pulled forward by the front end of the operating wire 12, thereby bending the first flexible pipe 11 in the other direction Y. Conversely, when the operating wire 12 is pulled backward, the front ends of both the operating wire 12 and the first flexible tube 11 move backward, causing the first flexible tube 11 to compress and deform in the front-rear direction between itself and the support 14, thereby increasing the bending rigidity of the first flexible tube 11. As a result, it becomes possible to operate the operating wire 12 differently for bending the first flexible tube 11 and for increasing the bending rigidity of the first flexible tube 11, making it possible to easily adjust the bending deformation and bending rigidity of the first flexible tube 11.
[0053] At least the front end of the support 14 is formed to have multiple slits S so as to bend and deform in accordance with the operation of the operating wire 12, and the flexible region L1 includes at least the portion of the medical wire 1 located forward of the rear end 11b of the first flexible tube 11, and the portion of the support 14 where at least the front end is located. As a result, the length of the flexible region L1 can be secured, and the bending rigidity at each position in the front-rear direction of the flexible region L1 can be easily adjusted, making it possible to obtain a medical wire 1 that can be smoothly bent into a desired shape when the operating wire 12 is operated.
[0054] The tip member 16 is made of an X-ray opaque material. Therefore, for example, when performing a procedure using the medical wire 1 under X-ray fluoroscopy, the tip member 16 can also be seen.
[0055] Next, a medical wire 2 according to a second embodiment of the present invention will be described with reference to Figure 3. In this second embodiment, the same reference numerals are used for parts that are the same as those in the first embodiment, and their descriptions are omitted; only the differences will be described.
[0056] In the medical wire 2 of this embodiment, the front end of the operating wire 12 is supported on the receiving surface 27 of the tip member 16, extending 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 when viewed from the left and right directions, and intersecting with the central axis O1 of the first flexible tube 11. The portion of the operating wire 12 located behind the front end extends straight in the front-rear direction, while the front end is bent so as it approaches the front end surface (forward), it extends in the other direction Y from a position displaced in one direction X with respect to the central axis O1. No through hole is formed in the tip member 16. The left-right positions of the front end of the operating wire 12 and the central axis O1 of the first flexible tube 11 coincide with each other. The front end of the operating wire 12 may be located away from the central axis O1 of the first flexible tube 11 in the left-right direction. The receiving surface 27 is formed on the outer circumferential surface of the rear end of the insertion shaft 28 of the tip member 16, and extends from a position displaced in one direction X with respect to the central axis O1 towards the other direction Y as it moves from the rear toward the front. When viewed from the left or right direction, the receiving surface 27 intersects with the central axis O1. The receiving surface 27 is provided over the entire left-right area of the insertion shaft 28. The receiving surface 27 faces diagonally backward toward the other direction Y.
[0057] As described above, according to the medical wire 2 of this embodiment, the front end of the operating wire 12 is supported on the receiving surface 27 of the tip member 16, extending 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 when viewed from the left and right directions, and intersecting with the central axis O1 of the first flexible tube 11. Furthermore, the operating wire 12 is provided with at least a first region 18 and a second region 19 which are positioned at different locations in the front-rear direction. For this reason, similar to the first embodiment, a medical wire 2 can be obtained that can be smoothly bent into a desired shape when the operating wire 12 is operated, and the ease of assembly of the medical wire 2 can be improved. Since the front end of the operating wire 12 is supported on the receiving surface 27 in a state intersecting with the central axis O1 of the first flexible tube 11, the front end of the operating wire 12 is less likely to come off the front fixing member 25, and the joint strength between the front end of the operating wire 12 and the front fixing member 25 can be improved.
[0058] Next, a medical wire 3 according to the third embodiment of the present invention will be described with reference to Figure 4. In this third embodiment, the same reference numerals are used for parts that are the same as those in the second embodiment, and their descriptions are omitted; only the differences will be described.
[0059] In the medical wire 3 of this embodiment, the front end of the operating wire 12 and the front end of the second flexible tube 15 are supported on the receiving surface 27 of the tip member 16, and when viewed from the left and right directions, they extend in the other direction Y from a position displaced in one direction X with respect to the central axis O1 as they move toward the front end opening edge (forward) of the operating wire 12 and the second flexible tube 15, and intersect with the central axis O1 of the first flexible tube 11. The front end of the operating wire 12 and the front end opening edge of the second flexible tube 15 face diagonally forward in the other direction Y. The front end of the operating wire 12 and the front end opening edge of the second flexible tube 15 are close to the inner circumferential surface of the first flexible tube 11. The front end of the operating wire 12 and the front end of the second flexible tube 15 are embedded in the front fixing member 25.
[0060] 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 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 part 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. In the illustrated example, no slit S is formed in the support 14, and the portion of the medical wire 1 located forward from 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.
[0061] As described above, in the medical wire 3 according to this embodiment, the front end of the operating wire 12 is supported on the receiving surface 27 of the tip member 16, extending 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 when viewed from the left and right directions, and intersecting with the central axis O1 of the first flexible tube 11. Furthermore, the operating wire 12 is provided with at least a first region 18 and a second region 19 which are positioned at different locations in the front-rear direction. For this reason, similar to the first embodiment, a medical wire 3 can be obtained that can be smoothly bent into a desired shape when the operating wire 12 is operated, and the ease of assembly of the medical wire 3 can be improved.
[0062] 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. Therefore, when manufacturing the medical wire 3, the radial relative positions of the support 14 and the first flexible tube 11 can be determined with high precision, and the support 14 and the first flexible tube 11 can be strongly joined to each other.
[0063] Next, a medical wire 4 according to the fourth embodiment of the present invention will be described with reference to Figure 5. In this fourth embodiment, the same reference numerals are used for parts that are the same as those in the third embodiment, and their descriptions are omitted; only the differences will be described.
[0064] In the medical wire 4 of this embodiment, the diameter of the front end of the second flexible tube 15 is larger than the diameter of the portion located behind the front end. The insertion shaft 28 of the tip member 16 is inserted inside the front end of the second flexible tube 15. The insertion shaft 28 has a surface facing in the other direction Y and a back surface facing in the one direction X, and when viewed from the front-to-back direction, it has a rectangular shape that is long in the left-to-right direction.
[0065] The portion of the operating wire 12 located behind its front end is positioned in one direction X from the surface of the insertion shaft 28 and extends straight in the front-rear direction. The front end of the operating wire 12 bends from a position displaced in one direction X with respect to the central axis O1 towards the front end surface, and then extends forward along the surface of the insertion shaft 28. That is, the surface of the insertion shaft 28 is the receiving surface 27 of the tip member 16 that supports the front end of the operating wire 12, extending from a position displaced in one direction X with respect to the central axis O1 towards the front end surface (forward) of the operating wire 12 when viewed from the left and right directions, and intersecting with the central axis O1 of the first flexible tube body 11. The front end surface of the operating wire 12 faces forward and is in contact with or close to the rear end surface of the protruding shaft 29 of the tip member 16.
[0066] As described above, in the medical wire 4 according to this embodiment, the front end of the operating wire 12 is supported on the receiving surface 27 of the tip member 16, extending 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 when viewed from the left and right directions, and intersecting with the central axis O1 of the first flexible tube 11. Furthermore, the operating wire 12 comprises at least a first region 18 and a second region 19 provided at different positions in the front-rear direction, and 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. For this reason, it has the same effects as the third embodiment.
[0067] It should be noted that the technical scope of the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention.
[0068] For example, medical wires 1 to 4 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, 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, starting from the first boundary 26 between the first region 18 and the second region 19. For example, when operating medical wires 1 to 4, 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.
[0069] A forward-facing flat surface may be formed at the front end of the protruding shaft 29. In this case, a large compressive load in the front-rear direction is generated on the medical wires 1 to 4 when they are operated.
[0070] The first boundary portion 26 and the second boundary portion 34 may be planes facing forward. The front-rear positions of the first boundary portion 26 and the second boundary portion 34 in the flexible region L1 may be changed as appropriate. For example, the first boundary portion 26 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.
[0071] 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.
[0072] 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.
[0073] Embodiments of the present invention are as follows, for example: <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, respectively, wherein the front ends of the first flexible tube and the operating wire are each provided with a tip member to which they are fixed, the tip member having a receiving surface that supports the front end of the operating wire 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, and the operating wire comprising 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. <2> The medical wire according to <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 greater than or equal to the bending rigidity of the second region. <3> The medical wire according to <1> or <2>, wherein at least the front end of the support has a plurality of circumferentially extending slits formed at intervals in the front-rear direction, and at least the portion of the medical wire located forward of the rear end of the first flexible tube, and at least the portion of the support where the front end is located, is a flexible region that can be bent and deformed in accordance with the operation of the operating wire. <4> The medical wire according to any one of <1> to <3>, wherein at least the front end of the support is inserted into and fixed inside the rear end of the first flexible tube. <5> The medical wire according to any one of <1> to <4>, wherein the tip member is made of an X-ray opaque material.<6> 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 ends of the first flexible tube and the operating wire are each fitted with a tip member, the tip member being made of an X-ray opaque material.
[0074] 1, 2, 3, 4 Medical wire 11 First flexible tube 11b Rear end 12 Operating wire 14 Support 16 Tip member 18 First region 19 Second region 20 Rigid portion 27 Receiving surface L1 Flexible region L2 Rigid region O1 Central axis of the first flexible tube S Slit 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; an operating wire extending in the front-rear direction and integrally inserted inside the first flexible tube and the support; and a tip member to which the front ends of the first flexible tube and the operating wire are fixed, wherein the tip member has a receiving surface formed thereon that supports the front end of the operating wire 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, and 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.
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.
3. The medical wire according to claim 1 or 2, wherein at least the front end of the support has a plurality of circumferentially extending slits formed at intervals in the front-rear direction, and at least the portion of the medical wire located in front of the rear end of the first flexible tube, and at least the portion of the support where the front end is located, are flexible regions that can be bent and deformed in accordance with the operation of the operating wire.
4. The medical wire according to claim 1 or 2, wherein at least the front end of the support is inserted into and fixed inside the rear end of the first flexible tube.
5. The medical wire according to claim 1 or 2, wherein the tip member is formed of an X-ray opaque material.