Medical wire

Abstract

The present invention comprises a first flexible tube body (11) that extends in the longitudinal direction and is formed so as to be capable of bending deformation, an operation wire (12) that extends in the longitudinal direction and is inserted inside the first flexible tube body (11), and a support body (14) that is fixed to the rear-end part of the first flexible tube body (11). The front-end part of the operation wire (12) is fixed to the front- end part of the first flexible tube body (11) in a state of being set apart from the center axis (O1) of the first flexible tube body (11) in one radial direction. An operation part (13) to which the operation wire is fixed and which is capable of moving in the longitudinal direction with respect to the support body is provided to the rear of the support body. The operation part is formed in a cylindrical shape extending in the longitudinal direction. The rear-end opening of the operation part is closed by a fixation member (24). The rear-end part of the operation wire is embedded in the fixation member. A locking projection (12b) that protrudes further in the radial direction than the portion of the operation wire positioned between the rear-end part and the front-end part is formed at the rear-end part of the operation wire.

Description

Medical Wire

[0001] The present invention relates to a medical wire such as a guidewire. This application claims priority to Japanese Patent Application No. 2023-219739, filed on December 26, 2023, the contents of which are incorporated herein by reference.

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

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

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

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

[0006] A medical wire according to a first aspect of the present invention includes a first flexible tubular body extending in a front-rear direction and formed to be bendable and deformable, a control wire extending in the front-rear direction and inserted inside the first flexible tubular body, and a support body fixed to a rear end of the first flexible tubular body, wherein the front end of the control wire is fixed to the front end of the first flexible tubular body in a state spaced apart in one radial direction from a central axis of the first flexible tubular body, and an control unit to which the control wire is fixed and which is movable in the front-rear direction relative to the support body is provided rearward of the support, the control unit being formed in a cylindrical shape extending in the front-rear direction, a rear end opening of the control unit being closed by a fixing member, the rear end of the control wire being embedded in the fixing member, and a locking protrusion formed on the rear end of the control wire protruding radially from a portion of the control wire located between the rear end and the front end.

[0007] A medical wire according to a second aspect of the present invention includes a first flexible tubular body extending in the front-rear direction and formed to be bendable and deformable, a manipulation wire extending in the front-rear direction and inserted inside the first flexible tubular body, and a support body fixed to the rear end of the first flexible tubular body, wherein the front end of the manipulation wire is fixed to the front end of the first flexible tubular body in a state spaced apart in one radial direction from the central axis of the first flexible tubular body, and a manipulation unit to which the manipulation wire is fixed and which is movable in the front-rear direction relative to the support body is provided behind the support body, the manipulation unit being formed in a cylindrical shape extending in the front-rear direction, and the rear end of the manipulation wire protrudes rearward from a rear end opening of the manipulation unit and is bent radially to be engaged with the outer surface of the manipulation unit.

[0008] A medical wire according to a third aspect of the present invention includes a first flexible tubular body extending in the front-rear direction and formed to be bendable and deformable, a control wire extending in the front-rear direction and inserted inside the first flexible tubular body, and a support body fixed to a rear end of the first flexible tubular body, wherein the front end of the control wire is fixed to the front end of the first flexible tubular body in a state spaced apart in one of the radial directions from the central axis of the first flexible tubular body, and a control unit to which the control wire is fixed and which is movable in the front-rear direction relative to the support body is provided rearward of the support, the control unit being formed in a cylindrical shape extending in the front-rear direction, a rear end opening of the control unit being closed by a fixing member, the rear end of the control wire being embedded in the fixing member, and the thermal expansion coefficients of the materials forming the control wire, the fixing member, and the control unit decreasing in this order.

[0009] According to the medical wires of the first to third aspects of the present invention, the front end of the manipulation wire is fixed to the front end of the first flexible tubular body while being spaced apart in one radial direction from the central axis of the first flexible tubular body. Therefore, when the manipulation wire is pulled rearward relative to the support body, the first flexible tubular body undergoes compressive deformation and bends in a specific radial direction. By manipulating the manipulation wire and bending the front end of the medical wire in a specific direction, a blood vessel can be selected at a vascular bifurcation and the medical wire can be advanced into the target blood vessel. This reduces the physician's dependence on the sense of manipulation when guiding the medical wire along the blood vessel to reach a chronic total occlusion lesion or the like, and eliminates the need to insert or remove the medical wire from the blood vessel to fine-tune the curvature of the front end of the medical wire outside the body. Furthermore, when the manipulation wire is pulled rearward relative to the support body, the front ends of the manipulation wire and the first flexible tubular body move rearward, compressing and deforming the first flexible tubular body in the front-to-rear direction between the support body and the first flexible tubular body, thereby increasing the bending rigidity of the first flexible tubular body. Therefore, by manipulating the manipulation wire while the medical wire is inserted into a blood vessel, the bending rigidity of the first flexible tubular body can be changed. As a result, when penetrating a chronic total occlusion or the like with the medical wire, the bending rigidity of the first flexible tubular body is kept low until the medical wire enters the blood vessel and reaches the chronic total occlusion or the like within the blood vessel. Then, when the medical wire is thrust into the chronic total occlusion or the like and penetrates the chronic total occlusion or the like with the medical wire, the manipulation wire is pulled rearward relative to the support body to increase the bending rigidity of the first flexible tubular body. After penetrating the chronic total occlusion or the like with the medical wire, the manipulation of the manipulation wire can be released to return the bending rigidity of the first flexible tubular body to its original low state. This eliminates the need to use different medical wires with different bending rigidities by inserting and removing them from the blood vessel or the like to penetrate the chronic total occlusion or the like. As a result, the surgical time can be shortened.

[0010] According to the medical wires of the first to third aspects of the present invention, the operating unit to which the operating wire is fixed is provided behind the support, and therefore, the operability of the medical wire can be improved by operating the operating unit compared to when the operating wire is directly operated.

[0011] According to the medical wire of the first aspect of the present invention, the rear end of the manipulation wire is embedded in a fixing member that closes the rear end opening of the manipulation section, and a locking protrusion is formed on the rear end of the manipulation wire, protruding radially from a portion of the manipulation wire located between the rear end and the front end. Therefore, the locking protrusion is hooked on the fixing member in the front-rear direction, preventing the rear end of the manipulation wire from coming off the manipulation section when the manipulation section is operated. According to the medical wire of the second aspect of the present invention, the rear end of the manipulation wire protrudes rearward from the rear end opening of the manipulation section and is bent radially to be locked on the outer surface of the manipulation section. Therefore, preventing the rear end of the manipulation wire from coming off the manipulation section when the manipulation section is operated. According to the medical wire of the third aspect of the present invention, the rear end of the manipulation wire is embedded in a fixing member that closes the rear end opening of the manipulation section, and the thermal expansion coefficients of the materials forming the manipulation wire, the fixing member, and the manipulation section decrease in order. Therefore, for example, by manufacturing the medical wire at an ambient temperature lower than room temperature, when the medical wire is used at room temperature, the fixing member has a larger expansion coefficient than the operating section, so that the fixing member is radially tightened by the operating section, and the operating wire has a larger expansion coefficient than the fixing member, so that the rear end of the operating wire is radially tightened by the fixing member, so that the rear end of the operating wire can be prevented from coming off the operating section when the operating section is operated.

[0012] A second flexible tube extending in the front-to-rear direction and formed to be bendable and deformable is inserted inside the first flexible tube, the operating wire is inserted inside the second flexible tube, the central axis of the second flexible tube and the front end of the operating wire are spaced apart from the central axis of the first flexible tube in one radial direction, the front end of the second flexible tube is fixed to at least one of the front ends of the first flexible tube and the operating wire, and the rear end of the second flexible tube, located rearward of the front end, is fixed to at least one of the support body and the rear end of the first flexible tube.

[0013] Because the second flexible tubular body is provided, when the manipulation wire is pulled rearward relative to the support body, the first and second flexible tubular bodies are compressed and deformed while bending in one radial direction, which makes it possible to easily adjust (design) the relationship between the manipulation force on the manipulation wire and the bending shape of the front end of the medical wire while maintaining the outer diameter of the medical wire, for example.

[0014] According to the above aspect of the present invention, the time required for surgery can be shortened.

[0015] FIG. 1 is a longitudinal cross-sectional view of a medical wire of a first embodiment; FIG. 2 is a partial longitudinal cross-sectional view of a first modified example of the medical wire of the first embodiment; FIG. 3 is a partial longitudinal cross-sectional view of a second modified example of the medical wire of the first embodiment; FIG. 4 is a partial longitudinal cross-sectional view of a third modified example of the medical wire of the first embodiment; FIG. 5 is a partial longitudinal cross-sectional view of a medical wire of a second embodiment; FIG. 6 is a longitudinal cross-sectional view of a medical wire of a third embodiment.

[0016] A first embodiment of the medical wire will be described below with reference to FIG. 1A . The medical wire 1 is a guidewire including a first flexible tubular body 11, an operating wire 12, an operating section 13, a support member 14, and a second flexible tubular body 15. The first flexible tubular body 11, the operating wire 12, the operating section 13, the support member 14, and the second flexible tubular body 15 are formed of, for example, a metal material. Note that the materials forming the first flexible tubular body 11, the operating wire 12, the operating section 13, the support member 14, and the second flexible tubular body 15 may be changed as appropriate. The second flexible tubular body 15 may not be provided.

[0017] The operation unit 13 and the support body 14 are formed in a cylindrical shape and disposed coaxially with the central axis O1 of the first flexible tubular body 11. Hereinafter, the side where the first flexible tubular body 11 is located with respect to the support body 14 in the direction in which the central axis O1 extends will be referred to as the front side, the side where the operation unit 13 is located with respect to the support body 14 in the direction in which the central axis O1 extends will be referred to as the rear side, and the direction in which the central axis O1 extends will be referred to as the front-rear direction. A direction intersecting the central axis O1 as viewed from the front-rear direction will be referred to as the radial direction, and a direction going around the central axis O1 as viewed from the front-rear direction will be referred to as the circumferential direction.

[0018] The first flexible tubular body 11 extends in the front-rear direction and is formed to be bendable. The first flexible tubular body 11 is a coil spring extending in the front-rear direction. The outer diameter of the first flexible tubular body 11 is large enough to be inserted into a blood vessel (e.g., 0.2 mm to 1.0 mm). The outer shape and size of the first flexible tubular body 11 as viewed in the front-rear direction are constant over the entire length in the front-rear direction. The diameter of the wire material forming the first flexible tubular body 11 is constant over the entire length.

[0019] The diameter of the wire forming the first flexible tubular body 11 does not have to be constant along its entire length, and the outer shape and size of the first flexible tubular body 11 as viewed in the front-rear direction do not have to be constant along its entire length in the front-rear direction. For example, the outer diameter of the first flexible tubular body 11 may decrease toward the front. The first flexible tubular body 11 is not limited to a coil spring, and may be, for example, a tubular body having a peripheral wall that extends continuously along its entire length in both the front-rear direction and the circumferential direction.

[0020] The support body 14 is fixed to the rear end of the first flexible tubular body 11. The support body 14 extends in the front-rear direction and is formed to be bendable. The rear end opening edge of the first flexible tubular body 11 abuts against the front end opening edge of the support body 14 in the front-rear direction. The front end of the support body 14 and the rear end of the first flexible tubular body 11 are fixed together by, for example, soldering, brazing, adhesive, or crimping. In the illustrated example, a cylindrical intermediate fixing member 23 made of, for example, solder, brazing material, or adhesive extends forward from the front end of the support body 14. The outer peripheral surface of the intermediate fixing member 23 is seamlessly connected to the outer peripheral surfaces of the support body 14 and the first flexible tubular body 11 in the front-rear direction.

[0021] The outer diameter of the support 14 is equal to the outer diameter of the first flexible tubular body 11 and is large enough to be inserted into a blood vessel (e.g., 0.2 mm to 1.0 mm). The outer shape and size of the support 14 as viewed in the front-rear direction are constant over the entire length in the front-rear direction. Note that the outer shape and size of the support 14 as viewed in the front-rear direction do not have to be constant over the entire length in the front-rear direction. For example, the outer diameter of the support 14 may decrease toward the front. The outer shapes and sizes of the support 14 and the first flexible tubular body 11 as viewed in the front-rear direction may be different from each other. In this case, it is preferable that the support 14 does not protrude radially outward from the outer circumferential surface of the first flexible tubular body 11 as viewed in the front-rear direction.

[0022] The operation unit 13 is provided behind the support body 14. The operation unit 13 protrudes rearward from the support body 14. The operation unit 13 is provided so as to be movable in the front-rear direction relative to the support body 14. In the illustrated example, the rear end of the support body 14 is inserted into the front portion of the operation unit 13. Note that the front end opening edge of the operation unit 13 and the rear end opening edge of the support body 14 may face each other in the front-rear direction, or the front portion of the operation unit 13 may be inserted into the rear end of the support body 14. The rear end of the operation wire 12 is fixed to the operation unit 13 by, for example, soldering, brazing, adhesive, or crimping. In the illustrated example, the rear end opening of the operation unit 13 is closed by a rear fixing member 24 (fixing member) made of, for example, a solder material, a brazing material, or an adhesive, and the rear end of the operation wire 12 is embedded in the rear fixing member 24.

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

[0024] The operation wire 12 extends straight in the front-rear direction. Note that the operation wire 12 may extend in the front-rear direction while being bent, for example. The rear portion of the operation wire 12 protrudes rearward from the support body 14. Of the front end portion of the operation wire 12, a protruding portion 12a protruding forward from the first flexible tubular body 11 is bent in one radial direction and engaged with the front-end opening edge of the first flexible tubular body 11. The protruding portion 12a of the operation wire 12 is located at the same radial position as, or radially inward from, the outer circumferential surface of the front end portion of the first flexible tubular body 11. The protruding portion 12a of the operation wire 12 is bent in one radial direction and folded back rearward, with the distal end surface of the operation wire 12 facing rearward. The distal end surface of the operation wire 12 abuts against or is close to the front-end opening edge of the first flexible tubular body 11. Note that the distal end surface of the operation wire 12 may face in one radial direction.

[0025] In the illustrated example, the front end opening of the first flexible tubular body 11 is closed by a front fixing member 25 made of, for example, solder, brazing material, or adhesive. The outer peripheral surface of the front fixing member 25 is connected to the outer peripheral surface of the first flexible tubular body 11 without any step in the front-to-rear direction. The front end of the operation wire 12, including the protruding portion 12a, is embedded in the front fixing member 25.

[0026] The bending rigidity of the intermediate section 11a of the first flexible tubular body 11, which is located between the front end (front fixing member 25) and the rear end (middle fixing member 23), decreases from the rear to the front. In the example shown, the first flexible tubular body 11 includes a first hard tubular section 22 having high bending rigidity, and a pair of first soft tubular sections 21 which have lower bending rigidity than the first hard tubular section 22 and sandwich the first hard tubular section 22 in the front-to-rear direction. Of the pair of first soft tubular sections 21, the number of turns of the first soft tubular section 21 located on the front side is greater than the number of turns of the first soft tubular section 21 located on the rear side. Note that the number of turns of the former may be equal to or less than the number of turns of the latter.

[0027] The first soft tube section 21 is formed so that the distance (inter-wire gap) between adjacent wire members in the front-to-rear direction is wider than that of the first hard tube section 22. As a result, the bending rigidity of the first soft tube section 21 is smaller than that of the first hard tube section 22, making it easier to flex flexibly to follow the bending of the blood vessel. In the illustrated example, adjacent wire members in the front-to-rear direction in the first hard tube section 22 abut against each other. In other words, the first hard tube section 22 is formed as a tightly wound coil spring. As a result, in the intermediate section 11a of the first flexible tube 11, the first hard tube section 22 is easier to flex flexibly to follow the bending deformation of the first soft tube section 21.

[0028] Of the pair of first soft tube sections 21, a front portion of the first soft tube section 21 located on the front side is joined or adhered to the front fixing member 25, and a rear portion of this first soft tube section 21 is located between the front fixing member 25 and the intermediate fixing member 23. Of the pair of first soft tube sections 21, the first soft tube section 21 located on the rear side is joined or adhered over its entire length to the intermediate fixing member 23. Therefore, of the first flexible tube 11, the intermediate section 11a located between the front fixing member 25 and the intermediate fixing member 23 is composed of the entire first hard tube section 22 and the rear portion of the first soft tube section 21 located on the front side of the pair of first soft tube sections 21. As a result, the bending rigidity of the intermediate section 11a of the first flexible tube 11 decreases stepwise from the rear to the front. Note that the bending rigidity of the intermediate section 11a of the first flexible tube 11 may also decrease linearly from the rear to the front. In the illustrated example, the length in the front-rear direction of the first hard pipe section 22 is longer than the length in the front-rear direction of the rear part of the first soft pipe section 21 that is located on the front side of the pair of first soft pipe sections 21. Note that the length of the former may be shorter than the length of the latter.

[0029] The second flexible tubular body 15 extends in the front-rear direction and is formed to be bendable. The second flexible tubular body 15 is inserted inside the first flexible tubular body 11. The front end of the second flexible tubular body 15 is fixed to at least one of the front ends of the first flexible tubular body 11 and the operation wire 12, and the rear end of the second flexible tubular body 15, which is located rearward of the front end, is fixed to at least one of the support body 14 and the rear end of the first flexible tubular body 11. The second flexible tubular body 15 protrudes in both the front-rear direction from the first flexible tubular body 11. Note that the second flexible tubular body 15 does not have to protrude in the front-rear direction from the first flexible tubular body 11.

[0030] At least one of the first flexible tubular body 11 and the second flexible tubular body 15 is a coil spring extending in the front-rear direction. In the illustrated example, both the first flexible tubular body 11 and the second flexible tubular body 15 are coil springs extending in the front-rear direction. The winding directions of the first flexible tubular body 11 and the second flexible tubular body 15 are opposite to each other. However, the winding directions of the first flexible tubular body 11 and the second flexible tubular body 15 may be the same as each other. Either one of the first flexible tubular body 11 and the second flexible tubular body 15 is not limited to a coil spring and may be, for example, a tubular body having a peripheral wall that extends continuously over the entire length in both the front-rear direction and the circumferential direction.

[0031] The bending rigidity of the intermediate section 15a of the second flexible tube 15, which is located between the front end section (front fixing member 25) and the rear section (middle fixing member 23), decreases from rear to front. In the illustrated example, the second flexible tube 15 is configured by connecting a second soft tube section 31, which has low bending rigidity, and a second hard tube section 32, which has higher bending rigidity than the second soft tube section 31, in this order from front to rear. The second soft tube section 31 protrudes forward from the first flexible tube 11, and the second hard tube section 32 protrudes rearward from the first flexible tube 11. The length of the second soft tube section 31 in the front-to-rear direction is slightly shorter than the length of the second hard tube section 32 in the front-to-rear direction.

[0032] The second soft tube section 31 is formed so that the distance (inter-wire gap) between adjacent wire members in the front-to-rear direction is wider than that of the second hard tube section 32. As a result, the bending rigidity of the second soft tube section 31 is smaller than that of the second hard tube section 32, making it easier to flex flexibly to follow the bending of the blood vessel. In the illustrated example, adjacent wire members in the front-to-rear direction in the second hard tube section 32 abut against each other. In other words, the second hard tube section 32 is formed as a tightly wound coil spring. As a result, in the intermediate section 15a of the second flexible tube 15, the second hard tube section 32 is easier to flex flexibly to follow the bending deformation of the second soft tube section 31.

[0033] A front portion of the second soft tube section 31 is joined or bonded to the front fixing member 25. As a result, the front end of the second flexible tubular body 15 is fixed to the front end portions of the first flexible tubular body 11 and the operating wire 12 via the front fixing member 25. The rear portion of the second soft tube section 31 is located between the front fixing member 25 and the intermediate fixing member 23. The intermediate fixing member 23 is joined or bonded to the outer circumferential surface of a portion of the second hard tube section 32 located between the front end portion located inside the first flexible tubular body 11 and the rear end portion located inside the support body 14. As a result, the rear portion of the second flexible tubular body 15 located rearward of the front end portion is fixed to the support body 14 and the rear end portion of the first flexible tubular body 11 via the intermediate fixing member 23. In the illustrated example, the intermediate fixing member 23 does not close the inside of the second hard tube section 32, and the inside of the support body 14 is in communication with the rear portion of the second soft tube section 31 through the inside of the second hard tube section 32.

[0034] The intermediate section 15a of the second flexible tubular body 15, located between the front fixing member 25 and the middle fixing member 23, is composed of the rear section of the second soft tubular section 31 and the front end section of the second hard tubular section 32. As a result, the bending rigidity of the intermediate section 15a of the second flexible tubular body 15 decreases stepwise from the rear to the front. Alternatively, the bending rigidity of the intermediate section 15a of the second flexible tubular body 15 may decrease linearly from the rear to the front. In the illustrated example, the length in the front-rear direction of the rear section of the second soft tubular section 31 is longer than the length in the front-rear direction of the front end section of the second hard tubular section 32. Alternatively, the length of the former may be shorter than the length of the latter. Within the intermediate section 11a of the first flexible tubular body 11, the rear section of the second soft tubular section 31 straddles the boundary between the first hard tubular section 22 and the first soft tubular section 21 located at the front of the pair of first soft tubular sections 21 in the front-rear direction.

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

[0036] The protruding portion 12a of the operation wire 12 also protrudes forward from the second flexible tubular body 15, is bent in one radial direction, and is engaged with the edge of the front end opening of the second flexible tubular body 15. The protruding portion 12a of the operation wire 12 is bent back, and a circumferential portion of the front end portion of the second flexible tubular body 15 is sandwiched in the radial direction between two points of the front end portion of the operation wire 12, including the protruding portion 12a. The entire front end portion of the operation wire 12, including the protruding portion 12a, is embedded in the front fixing member 25.

[0037] The outer peripheral surface of the front portion of the support 14 and the outer peripheral surface of a portion of the medical wire 1 located forward of the front portion of the support 14 are coated with a hydrophilic material. This allows the medical wire 1 to be moved smoothly through blood vessels with less snagging. The outer peripheral surface of the portion of the medical wire 1 located rearward of the front portion of the support 14 is coated with a hydrophobic material. This makes it less likely for the hand operating the medical wire 1 to slip. The outer peripheral surface of the operating portion 13 does not need to be coated with a hydrophobic material. Examples of hydrophilic materials include polyvinylpyrrolidone, maleic acid-based resins, and hyaluronic acid-based resins. Examples of hydrophobic materials include fluorine-based resins (PTFE, PFA, etc.), silicone-based resins, etc.

[0038] In this embodiment, a locking protrusion 12b is formed at the rear end of the operation wire 12, protruding radially from a portion of the operation wire 12 located between the rear end and the front end. In the example shown in the figure, the locking protrusion 12b is formed by bending the rear end of the operation wire 12 radially and then folding it back forward. The entire locking protrusion 12b is embedded in the rear fixing member 24. This locking protrusion 12b protrudes radially in another direction opposite to the one direction from a portion of the operation wire 12 located between the rear end and the front end.

[0039] As shown in FIG. 1B , the locking protrusion 12b may be configured such that the rear end of the operating wire 12 is formed into a loop shape bent to draw a ring protruding in the radial direction. This locking protrusion 12b protrudes in the other radial direction, opposite to the one direction, from a portion of the operating wire 12 located between the rear end and the front end. As shown in FIG. 1C , the locking protrusion 12b may be configured such that the rear end of the operating wire 12 extends rearward with repeated concave and convex shapes in the radial direction (e.g., a wave shape). This locking protrusion 12b extends rearward with repeated convex and convex shapes in one radial direction. As shown in FIG. 1D , the locking protrusion 12b may be configured such that the rear end of the operating wire 12 is pressed radially to form a plate shape. This locking protrusion 12b is formed in a rectangular plate shape that is long in the front-to-rear direction and has a plate width in one radial direction, with the plate width increasing toward the rear. 1E, the locking protrusion 12b may be a bulging portion that bulges out in the radial direction at the rear end of the operating wire 12. This locking protrusion 12b may be formed, for example, in a spherical shape, and multiple locking protrusions 12b may be provided at intervals in the front-rear direction.

[0040] As described above, with the medical wire 1 according to this embodiment, the front end of the manipulation wire 12 is fixed to the front end of the first flexible tubular body 11 in a state spaced apart in one radial direction from the central axis O1 of the first flexible tubular body 11, so that when the manipulation wire 12 is pulled rearward relative to the support body 14, the first flexible tubular body 11 is compressed and deformed while bending in one radial direction, and by manipulating the manipulation wire 12, it is possible to select a blood vessel at a vascular bifurcation and advance the medical wire 1 into the target blood vessel while bending the front end of the medical wire 1 in a desired direction. This reduces the physician's dependency on the sense of manipulation when guiding the medical wire 1 along the blood vessel to reach a chronic total occlusion lesion or the like, and also eliminates the need to insert and remove the medical wire from the blood vessel to fine-tune the curvature of the front end of the medical wire outside the body.

[0041] Furthermore, when the manipulation wire 12 is pulled rearward relative to the support body 14, the front ends of the manipulation wire 12 and the first flexible tubular body 11 move rearward, and the first flexible tubular body 11 is compressed and deformed in the front-to-rear direction between the support body 14, thereby increasing the bending rigidity of the first flexible tubular body 11. Therefore, by manipulating the manipulation wire 12 while the medical wire 1 is inserted into a blood vessel, the bending rigidity of the first flexible tubular body 11 can be changed.

[0042] As a result, when the medical wire 1 is to penetrate a chronic total occlusion lesion or the like, the bending rigidity of the first flexible tubular body 11 is kept low until the medical wire 1 is advanced into a blood vessel and reaches the chronic total occlusion lesion or the like within the blood vessel, and when the medical wire 1 is thrust into the chronic total occlusion lesion or the like and penetrates the chronic total occlusion lesion or the like with the medical wire 1, the manipulation wire 12 is pulled rearward relative to the support part 14 to increase the bending rigidity of the first flexible tubular body 11, and after penetrating the chronic total occlusion lesion or the like, the manipulation of the manipulation wire 12 can be released to return the bending rigidity of the first flexible tubular body 11 to its original low state. This eliminates the need to use different medical wires with different bending rigidities by inserting and removing them from the blood vessel or the like to penetrate a chronic total occlusion lesion or the like.

[0043] As a result, the operation time can be reduced.

[0044] Since the operating section 13 to which the operating wire 12 is fixed is provided behind the support body 14, the operability of the medical wire 1 can be improved by operating the operating section 13 compared to when the operating wire 12 is directly operated.

[0045] The rear end of the operation wire 12 is embedded in a rear fixing member 24 that closes the rear end opening of the operation unit 13, and a locking protrusion 12b is formed at the rear end of the operation wire 12, protruding radially from a portion of the operation wire 12 that is located between the rear end and the front end. Therefore, the locking protrusion 12b is caught on the rear fixing member 24 in the front-rear direction, and it is possible to prevent the rear end of the operation wire 12 from coming off the operation unit 13 when the operation unit 13 is operated.

[0046] Since the second flexible tube 15 is provided, when the operating wire 12 is pulled backward relative to the support body 14, the first flexible tube 11 and the second flexible tube 15 are compressed and deformed while bending in one radial direction. This makes it possible to easily adjust (design) the relationship between the operating force on the operating wire 12 and the bending shape of the front end of the medical wire 1, for example, while maintaining the outer diameter of the medical wire 1.

[0047] Next, a medical wire 2 according to a second embodiment of the present invention will be described with reference to Fig. 2. In this second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and their description will be omitted, with only the differences being described.

[0048] In the medical wire 2 of this embodiment, the rear end 12c of the operation wire 12 protrudes rearward from the rear end opening of the operation section 13, is bent radially, and is engaged with the outer surface of the operation section 13. In the illustrated example, the rear end 12c of the operation wire 12 radially straddles the edge of the rear end opening of the operation section 13, is wound around the outer peripheral surface of the operation section 13 multiple times, and extends forward. The rear end 12c of the operation wire 12 is fixed to the outer peripheral surface of the operation section 13 by, for example, soldering, brazing, or adhesive bonding. The rear end 12c of the operation wire 12 may extend straight in the front-rear direction on the outer peripheral surface of the operation section 13. The rear end 12c of the operation wire 12 may not reach the outer peripheral surface facing radially out of the outer surface of the operation section 13, but may only abut and engage with the edge of the rear end opening facing rearward.

[0049] As described above, the medical wire 2 according to this embodiment also has the same effects as the medical wire 1 shown in Fig. 1A. Furthermore, the rear end 12c of the manipulation wire 12 protrudes rearward from the rear end opening of the manipulation unit 13, is bent radially, and is engaged with the outer surface of the manipulation unit 13, so that the rear end 12c of the manipulation wire 12 can be prevented from coming off the manipulation unit 13 when the manipulation unit 13 is operated.

[0050] Next, a medical wire 3 according to a third embodiment of the present invention will be described with reference to Fig. 3. In this third embodiment, the same components as those in the first and second embodiments are denoted by the same reference numerals, and their description will be omitted, with only the differences being described.

[0051] In the medical wire 3 of this embodiment, the thermal expansion coefficients of the materials forming the manipulation wire 12, the rear fixing member 24, and the manipulation section 13 decrease in this order. That is, the material forming the manipulation wire 12 has the largest thermal expansion coefficient, and the material forming the manipulation section 13 has the smallest thermal expansion coefficient. Examples of such combinations of materials include, for the manipulation wire 12, the rear fixing member 24, and the manipulation section 13, in this order, SUS304 (stainless steel), Au-90Sn (tin alloy), and Ti6Al4V (titanium alloy); SUS631 (stainless steel), Au-3.15Si (gold alloy), and Ta (pure tantalum); A7075 (aluminum alloy), Sn-3Ag (tin alloy), and SUS304 (stainless steel); or A7075 (aluminum alloy), Ag-Cu-Ti-Sn (silver alloy), and W (pure tungsten). The rear end of the operation wire 12 extends straight in the front-rear direction and is entirely embedded in the rear fixing member 24. Note that in this embodiment, at least one of the locking protrusion 12b of the first embodiment and the rear end 12c of the operation wire 12 of the second embodiment may be applied.

[0052] 1A . Furthermore, the rear end of the manipulation wire 12 is embedded in the rear fixing member 24 that closes the rear-end opening of the manipulation section 13, and the thermal expansion coefficients of the materials forming the manipulation wire 12, rear fixing member 24, and manipulation section 13 decrease in this order. Therefore, for example, by manufacturing the medical wire 3 at an ambient temperature lower than room temperature, when the medical wire 3 is used at room temperature, the rear fixing member 24 has a larger expansion coefficient than the manipulation section 13, so that the rear fixing member 24 is radially tightened by the manipulation section 13, and the expansion coefficient of the manipulation wire 12 is larger than that of the rear fixing member 24, so that the rear end of the manipulation wire 12 is radially tightened by the rear fixing member 24, and the manipulation section 13 has a larger expansion coefficient than the rear fixing member 24, so that the rear end of the manipulation wire 12 is radially tightened by the rear fixing member 24, and this makes it possible to prevent the rear end of the manipulation wire 12 from coming off the manipulation section 13 when the manipulation section 13 is operated.

[0053] 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.

[0054] For example, the bending rigidity of the intermediate portions 11a, 15a may be the same over the entire length in the front-rear direction. The protruding portion 12a of the operation wire 12 may be bent in one radial direction so that the distal end surface of the operation wire 12 faces in one radial direction, and may be opposed to the front-rear direction while being spaced forward from the front-end opening edge of the first flexible tubular body 11. In this case, the front fixing member 25 may also be filled between the protruding portion 12a of the operation wire 12 and the front-end opening edge of the first flexible tubular body 11, and the front end of the operation wire 12, including the protruding portion 12a, may be embedded in the front fixing member 25. The second flexible tubular body 15 may not be provided, and the protruding portion 12a of the operation wire 12 may be bent in one radial direction and engaged with the front-end opening edge of the first flexible tubular body 11.

[0055] In addition, it is possible to replace the components in the above-described embodiments with well-known components as appropriate, without departing from the spirit of the present invention, and the above-described embodiments and variations may be combined as appropriate.

[0056] REFERENCE SIGNS LIST 1, 2, 3 Medical wire 11 First flexible tubular body 12 Operating wire 12b Locking projection 13 Operating portion 14 Support body 15 Second flexible tubular body 24 Rear fixing member (fixing member) O1 Central axis of first flexible tubular body O2 Central axis of second flexible tubular body

Claims

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

2. A medical wire comprising: a first flexible tube body extending in the front-rear direction and formed to be bendable; an operation wire extending in the front-rear direction and inserted inside the first flexible tube body; and a support body fixed to the rear end portion of the first flexible tube body, wherein a front end portion of the operation wire is fixed to a front end portion of the first flexible tube body while being separated from the central axis of the first flexible tube body in one direction in the radial direction, an operation portion, to which the operation wire is fixed and which is movable in the front-rear direction with respect to the support body, is provided behind the support body, the operation portion is formed in a cylindrical shape extending in the front-rear direction, a rear end portion of the operation wire protrudes rearward from a rear end opening of the operation portion and is bent in the radial direction to be locked to an outer surface of the operation portion.

3. A medical wire comprising: a first flexible tube body extending in the front-rear direction and formed to be bendable; an operation wire extending in the front-rear direction and inserted inside the first flexible tube body; and a support body fixed to the rear end portion of the first flexible tube body, wherein a front end portion of the operation wire is fixed to a front end portion of the first flexible tube body while being separated from the central axis of the first flexible tube body in one direction in the radial direction, an operation portion that is movable in the front-rear direction with respect to the support body while the operation wire is fixed is provided behind the support body, the operation portion is formed in a cylindrical shape extending in the front-rear direction, a rear end opening of the operation portion is closed by a fixing member, and a rear end portion of the operation wire is embedded in the fixing member, and the thermal expansion coefficients of the respective materials forming the operation wire, the fixing member, and the operation portion are decreasing in this order.

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

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