Medical instrument

Abstract

To provide a medical instrument capable of improving vascular selectivity, engagement force with respect to a blood vessel, or backup force.SOLUTION: A medical instrument 10 is a medical instrument 10 having a tubular body 30 extending from an operation unit 20 located on a proximal end side toward a distal end side, where the tubular body 30 is deformable into a predetermined curved shape by an operation at the operation unit 20, and includes a first deflectable portion 32 and a second deflectable portion 34 that are disposed at different positions in a longitudinal axis direction of the tubular body 30.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a medical device having a tubular body. [Background technology]

[0002] Intravascular treatment is performed to diagnose and treat lesions in blood vessels by percutaneously inserting long medical devices such as catheters. Because blood vessels have variable inner diameters and are tortuous, medical devices must have high selectivity to allow insertion into any desired blood vessel, high engagement force to maintain position in contact with the blood vessel, and high backup force to hold other devices passing through the device.

[0003] For this reason, for example, Patent Document 1 discloses a medical device having a deflectable portion at a part of a tubular body inserted into a blood vessel, which can be deflected by operating a site located outside the body. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] US Patent Application Publication No. 2017 / 080186 Summary of the Invention [Problem to be solved by the invention]

[0005] However, even with the medical instrument described in Patent Document 1, it may be difficult to deliver the medical instrument to the target blood vessel. For example, when a medical instrument inserted from the radial artery is to bend sharply in a large blood vessel such as the aortic arch to reach the small common carotid artery, it is difficult to deliver the medical instrument to the target blood vessel.

[0006] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a medical device that can improve blood vessel selectivity, engagement force with blood vessels, or backup force. [Means for solving the problem]

[0007] The medical device according to the present invention that achieves the above object is achieved by the invention described in (1) below.

[0008] (1) The medical device according to the present invention is a medical device having a tubular body extending from an operating section located at the base end to the tip end, and the tubular body has a plurality of deflectable sections that can be deformed into a predetermined curved shape by operating the operating section and are arranged at different positions in the longitudinal direction of the tubular body. [Effects of the Invention]

[0009] The medical device described in (1) above can improve vessel selectivity, engagement force with the vessel, or backup force by bending each of the deflectable portions located at different positions in the longitudinal direction of the tubular body, so that the deflectable portions can be shaped to suit the vessel within the vessel.

[0010] (2) In the medical device described in (1) above, the tubular body may include an outer tube and an inner tube at least a portion of which is disposed inside the outer tube and fixed to the outer tube by a fixing portion located distally of the deflectable portion, and which is slidable in the longitudinal direction relative to the outer tube on the proximal side of the fixing portion, and each of the deflectable portions may include an outer portion formed on the outer tube and an inner portion formed on the inner tube and located inside the outer portion, and the outer portion may include an outer hard portion formed on a portion of the circumferential direction and an outer soft portion formed at a position different from the outer hard portion in the circumferential direction and softer than the outer hard portion, and the inner portion may include an inner hard portion formed on a portion of the circumferential direction and an inner soft portion formed at a position different from the inner hard portion in the circumferential direction and softer than the outer hard portion, and at least a portion of the inner soft portion may be located inside the outer hard portion, As a result, by operating the operation unit by the surgeon, a compressive force is applied to the outer tube and a tensile force is applied to the inner tube, so that each of the deflectable portions can be deflected so as to bend toward the side of the outer soft portion of the outer tube and the side of the inner hard portion of the inner tube.Furthermore, by operating the operation unit by the surgeon, a tensile force is applied to the outer tube and a compressive force is applied to the inner tube, so that each of the deflectable portions can be deflected so as to bend toward the side of the outer hard portion of the outer tube and the side of the inner soft portion of the inner tube.

[0011] (3) In the medical device according to (1) or (2), when the at least two deflectable portions are simultaneously bent, the plane on which the central axes of the deflectable portions lie may coincide. This allows the medical device to arbitrarily deflect the deflectable portions on the plane on which the curved central axes of the at least two deflectable portions lie, thereby further improving blood vessel selectivity, engagement force with the blood vessel, or backup force.

[0012] (4) In the medical instrument described in any one of (1) to (3) above, the directions in which at least two of the deflectable portions are simultaneously bent may be the same direction, thereby allowing the medical instrument to be deflected to the same side at at least two locations in the longitudinal axis direction of the tubular body by operating the operating portion.

[0013] (5) In the medical instrument according to any one of (1) to (4) above, the at least two deflectable portions may have different radii of curvature, whereby the medical instrument can be curved with different radii of curvature at at least two locations in the longitudinal axis direction of the tubular body by operating the operating portion.

[0014] (6) In the medical instrument according to any one of (1) to (3) above, the directions in which at least two of the deflectable portions are simultaneously bent may be opposite to each other. This allows the medical instrument to bend at least two positions in the longitudinal axis direction of the tubular body to the same side by operating the operating portion.

[0015] (7) In the medical instrument described in (1) or (2) above, when the at least two deflectable portions are bent, the planes on which the central axes of the deflectable portions are located may be different from each other. This allows the medical instrument to bend a region of the tubular body that includes the at least two deflectable portions into a three-dimensionally curved shape by operating the operating unit.

[0016] (8) In the medical device according to any one of (1) to (7) above, the radius of curvature of the at least two deflectable portions may be smaller in a portion having a larger difference in hardness between the outer soft portion and the outer hard portion than in a portion having a smaller difference in hardness between the outer soft portion and the outer hard portion, thereby allowing a desired radius of curvature to be set by the difference in hardness between the outer soft portion and the outer hard portion.

[0017] (9) In the medical device according to any one of (1) to (8) above, the deflectable portions may have higher rigidity when deformed into the predetermined curved shape than when the deflectable portions are in a straight state. This allows each of the deflectable portions to have high rigidity, allowing the surgeon to easily insert at least one of the deflectable portions (e.g., the first deflectable portion 32) into the left common carotid artery A3. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a plan view showing a medical device according to a first embodiment. [Figure 2] 2(A) and 2(B) are diagrams showing the distal end of a medical device according to a first embodiment, in which (A) is a longitudinal cross-sectional view, (B) is a transverse cross-sectional view taken along line AA in FIG. 2(A), and (C) is a transverse cross-sectional view taken along line BB in FIG. 2(A). [Figure 3] FIG. 2 is a plan view showing the outer tube and the inner tube in a disassembled state. [Figure 4] FIG. 4 is a plan view illustrating the operation of the medical device according to the first embodiment. [Figure 5] 1 is a schematic diagram showing a medical device reaching the common carotid artery from the radial artery. [Figure 6] 1 is a schematic diagram showing a medical device for aspirating thrombus from the inferior vena cava. [Figure 7] 7A and 7B are diagrams showing a medical device according to a second embodiment, in which (A) is a plan view, (B) is a cross-sectional view taken along line CC in FIG. 7A, and (C) is a cross-sectional view taken along line DD in FIG. 7A. [Figure 8] FIG. 2 is a plan view showing the outer tube and the inner tube in a disassembled state. [Figure 9] FIG. 10 is a plan view illustrating the operation of the medical device according to the second embodiment. [Figure 10] FIG. 10 is a plan view showing an outer tube and an inner tube in an exploded state of the medical device according to the third embodiment. [Figure 11] FIG. 10 is a plan view of a medical device according to a third embodiment in a state where a deflectable portion is deflected. [Figure 12] 10A and 10B are plan views showing application examples of the medical device according to the third embodiment, in which (A) shows a Cobra-type catheter and (B) shows a Judkins-Left-type catheter. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the dimensional proportions in the drawings may be exaggerated for convenience of explanation and may differ from the actual proportions. In the following description, the side of a medical instrument that is operated by a surgeon will be referred to as the "proximal end" and the side that is inserted into the body will be referred to as the "distal end."

[0020] First Embodiment A medical device 10 according to a first embodiment of the present invention is a catheter that is inserted into the common carotid artery from the radial artery, as shown in Fig. 5. That is, the medical device 10 is used by an operator accessing it from the right or left radial artery and reaching the right common carotid artery A4 or the left common carotid artery A3.

[0021] As shown in FIGS. 1 to 3, the medical device 10 has an operating section 20 located on the proximal end side, and a tubular body 30 extending from the operating section 20 to the distal end side.

[0022] The tubular body 30 is flexible and has a lumen 31 formed in the approximate center thereof over the entire length. The tubular body 30 includes a first deflectable section 32 (deflectable section) located on the distal side, one second deflectable section 34 (deflectable section) located closer to the proximal end than the straight section, an intermediate section 33 located between the first deflectable section 32 and the second deflectable section 34, and a base section 35 located closer to the proximal end than the deflectable section.

[0023] The tubular body 30 may have a flexible tip at its distal end to prevent damage to the object it comes into contact with. The tubular body 30 may also have an X-ray opaque marker at its distal end. The outer surface of the distal end of the tubular body 30 may also be coated with a hydrophilic coating.

[0024] The first deflectable portion 32 can be deflected so as to be curved in a predetermined direction by the operator's operation of the operation portion 20. The central axis of the first deflectable portion 32 can be curved on a predetermined plane M.

[0025] The second deflectable portion 34 can be deflected by bending it in a predetermined direction through the surgeon's operation of the operation unit 20. The central axis of the second deflectable portion 34 can be bent on a predetermined plane M. The plane M on which the central axis of the first deflectable portion 32 curves and the plane M on which the central axis of the second deflectable portion 34 curves coincide with each other, but they do not have to coincide with each other.

[0026] The intermediate portion 33 is located between the base end of the first deflectable portion 32 and the tip end of the second deflectable portion 34, and has a straight or curved central axis. Note that the tube 30 does not necessarily have to have the intermediate portion 33.

[0027] The base portion 35 is a tubular portion that extends approximately linearly in the longitudinal direction between the second deflectable portion 34 and the operation portion 20. The base portion 35 may have a braided tube in which a plurality of metal wires are braided into a tubular shape, a coil in which at least one metal wire is wound helically, or a metal pipe in which at least one slit is formed.

[0028] At least a portion of the above-described tubular body 30 proximal to the distal end of the first deflectable section 32 is formed by an outer tube 40 and an inner tube 50, at least a portion of which is disposed inside the outer tube 40. The tubular body 30 has a fixed section 36, to which the inner tube 50 and the outer tube 40 are fixed, distal to the distal end of the first deflectable section 32. That is, the portion of the tubular body 30 proximal to the fixed section 36 is formed as a double-tube structure. The position of the fixed section 36 is not particularly limited as long as it is distal to the first deflectable section 32. The portions of the outer tube 40 and the inner tube 50 proximal to the fixed section 36 are in contact with each other so as to be slidable in the longitudinal direction. Preferably, the inner tube 50 and the outer tube 40 are in contact with each other proximal to the fixed section 36 with a small clearance that allows sliding movement.

[0029] The outer pipe 40 has a flexible outer pipe body 41 partially formed with a first outer opening 42 and a second outer opening 43, a first outer soft portion 44 disposed in the first outer opening 42, a second outer soft portion 45 disposed in the second outer opening 43, and elongated first outer reinforcing members 46 and second outer reinforcing members 47 formed from a material harder than the outer pipe body 41.

[0030] The first outer opening 42 is formed in a range in the longitudinal direction where the first deflectable portion 32 of the outer tube main body 41 is located. The first outer opening 42 is formed partially in the circumferential direction, for example, in a range of 1 to 359 degrees. The first outer opening 42 is preferably formed in a range of 45 to 315 degrees, more preferably 90 to 270 degrees.

[0031] The second outer opening 43 is formed in a range in the longitudinal direction where the second deflectable portion 34 of the outer tube main body 41 is located. The second outer opening 43 is formed partially in the circumferential direction, for example, in a range of 1 to 359 degrees. The second outer opening 43 is preferably formed in a range of 45 to 315 degrees, more preferably 90 to 270 degrees. The second outer opening 43 is positioned closer to the base end than the first outer opening 42 in the longitudinal direction of the outer tube main body 41, and is positioned on the opposite side of the circumferential direction of the outer tube main body 41 to the side where the first outer opening 42 is positioned.

[0032] The outer tube main body 41 has a first outer hard portion 48 in a range where the first deflectable portion 32 is located, at a position different in the circumferential direction from the range where the first outer opening 42 is formed.

[0033] The outer tube body 41 also has a second outer hard portion 49 at a position in the circumferential direction different from the range where the second outer opening 43 is formed, within the range where the second deflectable portion 34 is located. The hardness of the first outer hard portion 48 and the second outer hard portion 49 may be the same or different.

[0034] The first outer soft portion 44 is disposed and coupled to the first outer opening 42. The first outer soft portion 44 has a lower hardness than the outer tube body 41. The hardness can be defined by, for example, durometer hardness or Rockwell hardness. The first outer soft portion 44 and the first outer hard portion 48 are aligned in the circumferential direction and form a single tubular first outer portion 40A.

[0035] The second outer soft portion 45 is disposed to be coupled to the second outer opening 43. The second outer soft portion 45 has a lower hardness than the outer tube body 41. As an example, the outer tube body 41 has a durometer hardness of 72D, and the first outer soft portion 44 and the second outer soft portion 45 have a durometer hardness of 35D. The hardnesses of the first outer soft portion 44 and the second outer soft portion 45 may be the same or different. The second outer soft portion 45 and the second outer hard portion 49 are aligned in the circumferential direction and form a single tubular second outer portion 40B.

[0036] The tip of the first outer reinforcing member 46 is located distally of the first outer opening 42, and the base end of the first outer reinforcing member 46 is located proximal to the first outer opening 42. For example, the tip of the first outer reinforcing member 46 may be located at the tip of the outer pipe main body 41, but it may also be located proximal to the tip of the outer pipe main body 41 as long as it is distally of the first outer opening 42. The base end of the first outer reinforcing member 46 is located in the intermediate section 33. The first outer reinforcing member 46 is disposed at a specific position in the circumferential direction of the outer pipe main body 41, extending parallel to the longitudinal direction. In this embodiment, the first outer reinforcing member 46 is disposed embedded in the first outer hard portion 48. The first outer reinforcing member 46 may also be disposed so as to be in contact with the outer surface of the first outer hard portion 48, without being embedded in the first outer hard portion 48.

[0037] The tip of the second outer reinforcing member 47 is located distally of the second outer opening 43, and the base end of the second outer reinforcing member 47 is located proximally of the second outer opening 43. For example, the tip of the second outer reinforcing member 47 is located in the intermediate section 33. The base end of the second outer reinforcing member 47 may be located at the base end of the outer pipe main body 41, but may also be located distally of the base end of the outer pipe main body 41 as long as it is proximal to the second outer opening 43. The second outer reinforcing member 47 is disposed at a specific circumferential position of the outer pipe main body 41, extending parallel to the longitudinal direction. In this embodiment, the second outer reinforcing member 47 is disposed embedded in the second outer hard portion 49. The second outer reinforcing member 47 may be disposed so as to be in contact with the outer surface of the second outer hard portion 49 without being embedded in the second outer hard portion 49.

[0038] The first outer reinforcing member 46 and the second outer reinforcing member 47 are formed from, for example, a resin material such as Kevlar (registered trademark), glass fiber, carbon fiber, or a metal material such as stainless steel.

[0039] The inner pipe 50 has a flexible inner pipe body 51 having a first inner opening 52 and a second inner opening 53 formed in part thereof, a first inner soft portion 54 arranged in the first inner opening 52, a second inner soft portion 55 arranged in the second inner opening 53, and long first and second inner reinforcing members 56 and 57 formed from a material harder than the inner pipe body 51.

[0040] The first inner opening 52 is formed in a range in the longitudinal direction where the first deflectable portion 32 of the inner pipe main body 51 is located. The first inner opening 52 is formed partially in the circumferential direction, for example, in a range of 1 to 359 degrees. The first inner opening 52 is preferably formed in a range of 45 to 315 degrees, more preferably 90 to 270 degrees.

[0041] The second inner opening 53 is formed in a range in the longitudinal direction where the second deflectable portion 34 of the inner pipe main body 51 is located. The second inner opening 53 is formed partially in the circumferential direction, for example, in a range of 1 to 359 degrees. The second inner opening 53 is preferably formed in a range of 45 to 315 degrees, and more preferably 90 to 270 degrees. The second inner opening 53 is positioned closer to the base end than the first inner opening 52 in the longitudinal direction of the inner pipe main body 51, and is positioned on the opposite side of the inner pipe main body 51 in the circumferential direction to the side where the first inner opening 52 is positioned.

[0042] The inner pipe body 51 has a first inner hard portion 58 at a position in the circumferential direction different from the range where the first inner opening 52 is formed, within the range where the first deflectable portion 32 is located.

[0043] The inner tube 50 also has a second inner hard portion 59 at a position in the circumferential direction different from the range in which the second inner opening 53 is formed, within the range in which the second deflectable portion 34 is located.

[0044] The first inner soft portion 54 is disposed and connected to the first inner opening 52. The first inner soft portion 54 has a lower hardness than the inner pipe main body 51. The first inner soft portion 54 and the first inner hard portion 58 are aligned in the circumferential direction and form a single tubular first inner portion 50A.

[0045] The second inner soft portion 55 is disposed in connection with the second inner opening 53. The second inner soft portion 55 has a lower hardness than the inner pipe body 51. For example, the inner pipe body 51 has a durometer hardness of 72D, and the first inner soft portion 54 and the second inner soft portion 55 have a durometer hardness of 35D. The hardnesses of the first inner soft portion 54 and the second inner soft portion 55 may be the same or different. The second inner soft portion 55 and the second inner hard portion 59 are aligned in the circumferential direction and form a single tubular second inner portion 50B. The hardnesses of the second inner soft portion 55 and the second inner hard portion 59 may be the same or different.

[0046] The tip of the first inner reinforcing member 56 is located distally of the first inner opening 52, and the base end of the first inner reinforcing member 56 is located proximal to the first inner opening 52. For example, the tip of the first inner reinforcing member 56 may be located at the tip of the inner pipe main body 51, but it may also be located proximal to the tip of the inner pipe main body 51 as long as it is distally of the first inner opening 52. The base end of the first inner reinforcing member 56 is located in the intermediate section 33. The first inner reinforcing member 56 is disposed at a specific position in the circumferential direction of the inner pipe main body 51, extending parallel to the longitudinal direction. In this embodiment, the first inner reinforcing member 56 is disposed embedded in the first inner hard portion 58. The first inner reinforcing member 56 may be disposed so as to be in contact with the outer surface of the first inner hard portion 58 without being embedded in the first inner hard portion 58.

[0047] The tip of the second inner reinforcing member 57 is located distally of the second inner opening 53, and the base end of the second inner reinforcing member 57 is located proximally of the second inner opening 53. For example, the tip of the second inner reinforcing member 57 is located in the intermediate section 33. The base end of the second inner reinforcing member 57 may be located at the base end of the outer pipe main body 41, but may be located distally of the base end of the outer pipe main body 41 as long as it is proximal to the second inner opening 53. The second inner reinforcing member 57 is located at a specific circumferential position of the inner pipe main body 51, extending parallel to the longitudinal direction. In this embodiment, the second inner reinforcing member 57 is located embedded in the second inner hard portion 59. The second inner reinforcing member 57 may be located so as to be in contact with the outer surface of the second inner hard portion 59 without being embedded in the second inner hard portion 59.

[0048] The first inner reinforcing member 56 and the second inner reinforcing member 57 are formed from materials that can be used for the first outer reinforcing member 46 and the second outer reinforcing member 47 described above.

[0049] The first outer portion 40A of the outer pipe 40 and the first inner portion 50A of the inner pipe 50 form the first deflectable portion 32 of the pipe body 30. The first deflectable portion 32 is a portion that can be deflected to bend in a predetermined direction. At least a portion of the first inner soft portion 54 is located inside the first outer hard portion 48. At least a portion of the first inner hard portion 58 is located inside the first outer soft portion 44. In the circumferential direction, the first inner soft portion 54 is located on the opposite side of the first outer soft portion 44, and the first inner hard portion 58 is located on the opposite side of the first outer hard portion 48.

[0050] The second outer portion 40B of the outer pipe 40 and the second inner portion 50B of the inner pipe 50 form the second deflectable portion 34 of the pipe body 30. The second deflectable portion 34 is a portion that can be deflected to bend in a predetermined direction. At least a portion of the second inner soft portion 55 is located inside the second outer hard portion 49. At least a portion of the second inner hard portion 59 is located inside the second outer soft portion 45. In the circumferential direction, the second inner soft portion 55 is located on the opposite side of the second outer soft portion 45, and the second inner hard portion 59 is located on the opposite side of the second outer hard portion 49.

[0051] In the circumferential direction, the second inner soft portion 55 is located on the opposite side of the first inner soft portion 54, and the second inner hard portion 59 is located on the opposite side of the first inner hard portion 58. In addition, in the circumferential direction, the second outer soft portion 45 is located on the opposite side of the first outer soft portion 44, and the second outer hard portion 49 is located on the opposite side of the first outer hard portion 48.

[0052] The first outer soft portion 44, the first outer hard portion 48, the first inner soft portion 54, the first inner hard portion 58, the second outer soft portion 45, the second outer hard portion 49, the second inner soft portion 55, and the second inner hard portion 59 are formed from a resin such as polyamide, polyamide elastomer, polyurethane, polyethylene, polypropylene, polytetrafluoroethylene (PTFE), ethylene-tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), polyether ether ketone (PEEK), polyphenylene sulfide (PPS), or the like.

[0053] In this embodiment, the plane M on which the central axis of the tubular body 30, the central axis of the first outer reinforcing member 46, and the central axis of the first inner reinforcing member 56 are located coincides with the plane M on which the central axis of the tubular body 30, the central axis of the second outer reinforcing member 47, and the central axis of the second inner reinforcing member 57 are located. The first deflectable portion 32 has a structure that is plane-symmetrical with respect to the plane M. The second deflectable portion 34 also has a structure that is plane-symmetrical with respect to the plane M. The first deflectable portion 32 and the second deflectable portion 34 are structured to bend simultaneously on the plane M by the same operation of the operating portion 20. The first deflectable portion 32 and the second deflectable portion 34 bend simultaneously on opposite sides.

[0054] In this embodiment, the rigidity of each of the deflectable sections 32, 34 when deformed into a predetermined curved shape is higher than the rigidity of each of the deflectable sections 32, 34 when no compressive or tensile force is applied and the first operating section 21 and the second operating section 22 are not operated. This makes each of the deflectable sections 32, 34 highly rigid, allowing the surgeon to easily insert the first deflectable section 32 into the left common carotid artery A3.

[0055] When the first operating unit 21 and the second operating unit 22 are not operated and no compressive or tensile force is being applied, the rigidity of the deflectable units 32, 34 is lower than the rigidity of the tubular body 30 on the proximal side of the deflectable unit 34. This allows for high pushability due to the rigidity of the tubular body 30 on the proximal side of the deflectable unit 34, and the surgeon can easily reach the right subclavian artery A1 and the aortic arch A2.

[0056] The rigidity of each of the deflectable portions 32, 34 when deformed into a predetermined curved shape is equal to or higher than the rigidity of the tubular body 30 on the proximal side of the deflectable portion 34. As a result, when another medical instrument is advanced and operated deep inside the left common carotid artery A3 via the medical instrument 10 or a contrast agent is injected, the deflectable portions 32, 34 have a relatively high rigidity and are able to maintain the predetermined curved shape, thereby generating a high backup force. Note that the predetermined curved shape is a desired shape that appears when the operation unit 20 is operated, and does not include shapes that appear between the initial positions of the first operation unit 21 and the second operation unit 2 in this embodiment and the positions at which the desired shape is achieved.

[0057] The operation unit 20 has a first operation unit 21 fixed to the base end of the inner tube 50 and a second operation unit 22 fixed to the base end of the outer tube 40. The first operation unit 21 has a base end opening 23 that communicates with the lumen 31 of the tubular body 30. The second operation unit 22 is located more distal than the first operation unit 21 and is slidable in the longitudinal direction on the outer peripheral surface of the inner tube 50. The configuration of the operation unit 20 is not particularly limited. For example, the second operation unit 22 may be slidable relative to the first operation unit 21, rather than being slidable relative to the inner tube 50.

[0058] Next, the operation of the medical device 10 according to the first embodiment will be described.

[0059] Typically, when a long member with varying stiffness in the circumferential direction is subjected to a compressive force in the longitudinal direction (when the base end is pushed toward the tip and the tip is pushed toward the base end), the softer portion contracts more in the longitudinal direction than the harder portion, shortening and bending toward the softer portion. Conversely, when a long member with varying stiffness in the circumferential direction is subjected to a tensile force in the longitudinal direction (when the base end is pulled toward the base and the tip is pulled toward the tip), the softer portion stretches more in the longitudinal direction than the harder portion, lengthening and bending toward the harder portion.

[0060] 4, when the second operating part 22 moves distally relative to the first operating part 21, a compressive force acts on the outer tube 40 and a tensile force acts on the inner tube 50. As a result, the first deflectable part 32 bends toward the side where the first outer soft part 44 of the outer tube 40 is located and the first inner hard part 58 of the inner tube 50 is located. The second deflectable part 34 bends toward the side where the second outer soft part 45 of the outer tube 40 is located and the second inner hard part 59 of the inner tube 50 is located.

[0061] This allows the distal end of the medical instrument 10 to be deformed into, for example, a Simmons (registered trademark) type. The radius of curvature of the first deflectable portion 32 and the second deflectable portion 34 can be changed arbitrarily depending on the amount of movement of the second operating portion 22 or the first operating portion 21. The radius of curvature generated by the second deflectable portion 34 may be the same as, smaller than, or larger than the radius of curvature generated by the first deflectable portion 32.

[0062] The radius of curvature generated in the first deflectable portion 32 becomes smaller as the difference in hardness between the first outer soft portion 44 and the first outer hard portion 48 and the difference in hardness between the first inner soft portion 54 and the first inner hard portion 58 increases. Furthermore, the rigidity of the first deflectable portion 32 becomes higher as the total hardness of the first outer soft portion 44, the first outer hard portion 48, the first inner soft portion 54, and the first inner hard portion 58 increases.

[0063] The radius of curvature generated in the second deflectable portion 34 becomes smaller as the difference in hardness between the second outer soft portion 45 and the second outer hard portion 49 and the difference in hardness between the second inner soft portion 55 and the second inner hard portion 59 become larger. Furthermore, the rigidity of the second deflectable portion 34 becomes higher as the total hardness of the second outer soft portion 45, the second outer hard portion 49, the second inner soft portion 55, and the second inner hard portion 59 increases.

[0064] Next, an example will be described in which the structure of the medical device 10 according to the first embodiment is applied to a catheter that reaches the common carotid artery from the radial artery. Here, as shown in Fig. 5, an example will be described in which the medical device 10 is inserted from the right radial artery and placed in the left common carotid artery A3. Note that the surgeon may use the medical device 10 to reach the right common carotid artery A4 from the right radial artery, or may use the medical device 10 to reach the left common carotid artery A3 or the right common carotid artery A4 from the left radial artery.

[0065] The surgeon inserts a guidewire through the right radial artery, which has been punctured in a conventional manner, and inserts the medical device 10 into the blood vessel along the guidewire. The surgeon then brings the medical device 10 from the right subclavian artery A1 to the aortic arch A2.

[0066] 4, the surgeon moves the second operating part 22 toward the distal end relative to the first operating part 21. As a result, a compressive force acts on the outer tube 40, and a tensile force acts on the inner tube 50.

[0067] When a compressive force acts on the outer tube 40 and a tensile force acts on the inner tube 50, the first deflectable portion 32 and the second deflectable portion 34 bend to opposite sides on the plane M. As a result, the distal end of the medical device 10 is deformed into a shape close to a Simmons shape at the aortic arch A2. Note that the medical device 10 does not necessarily bend strictly on the plane M because it is subjected to various forces within the blood vessels.

[0068] Next, the surgeon inserts the curved first deflectable portion 32 into the left common carotid artery A3, as shown in Fig. 5. Using the second deflectable portion 34, which is bent by more than 90 degrees in the opposite direction to the first deflectable portion 32, the surgeon can easily insert the first deflectable portion 32 from the aortic arch A2 into the left common carotid artery A3.

[0069] Next, the surgeon engages the first deflectable portion 32 with the left common carotid artery A3. Because the first deflectable portion 32 has a curved shape, it can maintain contact with the left common carotid artery A3 and prevent unintended movement. Because the medical device 10 has the intermediate portion 33 between the first deflectable portion 32 and the second deflectable portion 34, the first deflectable portion 32 can be inserted deep into the left common carotid artery A3. If the medical device 10 has a locking mechanism that fixes the relative positions of the first operating portion 21 and the second operating portion 22, activating the locking mechanism can maintain the deflected shapes of the first deflectable portion 32 and the second deflectable portion 34 and effectively maintain their engagement with the left common carotid artery A3.

[0070] When removing the medical instrument 10, the surgeon returns the positional relationship between the first operating part 21 and the second operating part 22 to the original state. This causes the first deflectable part 32 and the second deflectable part 34 to return to their original linear shape, as shown in FIG. 1. This allows the surgeon to easily remove the medical instrument 10.

[0071] Next, an example will be described in which the structure of the medical device 10 according to the first embodiment is applied to a catheter for aspirating a thrombus C caught on an inferior vena cava filter 60 in the inferior vena cava A5, as shown in FIG. 6 . The surgeon inserts the medical device 10 through the iliac vein in the groin and brings it close to the inferior vena cava filter 60. Next, the surgeon moves the second operating unit 22 toward the distal end relative to the first operating unit 21. This applies a compressive force to the outer tube 40 and a tensile force to the inner tube 50. As a result, the first deflectable section 32 and the second deflectable section 34 bend in opposite directions, and the opening at the distal end of the tubular body 30 faces the distal end and is positioned approximately at the center of the inferior vena cava A5. The portion of the tubular body 30 proximal to the second deflectable section 34 remains substantially straight and in contact with the inner wall of the inferior vena cava A5 to maintain its position, or generates a high backup force when another medical device is advanced and operated or a contrast medium is injected into the inferior vena cava A5 via the medical device 10. Therefore, the opening at the tip of the tubular body 30 can easily retrieve the thrombus C caught in the center of the inferior vena cava filter 60. Furthermore, the medical device 10 can retrieve the thrombus caught on the side surface of the inferior vena cava filter 60 even when the first deflectable portion 32 and the second deflectable portion 34 are not deflected. Furthermore, by appropriately adjusting the relative positions of the first operating portion 21 and the second operating portion 22, the shapes of the first deflectable portion 32 and the second deflectable portion 34 can be changed. This makes it possible to align the tip of the medical device 10 with the position of the thrombus while checking the position of the thrombus on an X-ray angiogram.

[0072] As described above, the medical device 10 according to the first embodiment is a medical device 10 having a tubular body 30 extending from an operating section 20 located on the base end side to the tip end side, and the tubular body 30 has a plurality of deflectable sections (first deflectable section 32, second deflectable section 34) that can be deformed into a predetermined curved shape by operating the operating section 20 and are arranged at different positions in the longitudinal direction of the tubular body 30. As a result, by bending each of the deflectable sections located at different positions in the longitudinal direction of the tubular body 30, the medical device 10 can shape the deflectable sections within the blood vessel to suit the blood vessel, thereby improving blood vessel selectivity, engagement force with the blood vessel, and backup force.

[0073] The tube body 30 has an outer tube 40 and an inner tube 50, at least a portion of which is disposed inside the outer tube 40 and fixed to the outer tube 40 by a fixing portion 36 located distally of the deflectable portions (first deflectable portion 32, second deflectable portion 34), and which is slidable in the longitudinal direction relative to the outer tube 40 on the proximal side of the fixing portion 36, and each of the deflectable portions has an outer portion formed on the outer tube 40 and an inner portion formed on the inner tube 50 and located inside the outer portion, and the outer portion has an outer hard portion (first outer hard portion 48, second outer hard portion 49) formed in a part of the circumferential direction and an outer hard portion (second outer hard portion 49) different from the outer hard portion in the circumferential direction. and outer soft portions (first outer soft portion 44, second outer soft portion 45) that are formed at positions corresponding to the outer hard portion and are softer than the outer hard portion, and the inner portions (first inner hard portion 50A, second inner hard portion 50B) have inner hard portions (first inner hard portion 58, second inner hard portion 59) that are formed at parts of the circumferential direction, and inner soft portions (first inner soft portion 54, second inner soft portion 55) that are formed at positions different from the inner hard portions in the circumferential direction and are softer than the outer hard portions, at least a part of the inner soft portions is located inside the outer hard portions, and at least a part of the inner hard portions is located inside the outer soft portions. As a result, by operating the operating unit 20 by the surgeon, a compressive force acts on the outer tube 40 and a tensile force acts on the inner tube 50, and each of the deflectable portions can be deflected so as to bend toward the side of the outer soft portion of the outer tube 40 where the outer hard portion of the inner tube 50 is located and toward the side of the inner hard portion of the inner tube 50 where the inner hard portion of the inner tube 50 is located. In addition, by operating the operating unit 20 by the surgeon, a tensile force is applied to the outer tube 40 and a compressive force is applied to the inner tube 50, so that each of the deflectable portions can be deflected so as to bend toward the side where the outer hard portion of the outer tube 40 is located and the inner soft portion of the inner tube 50 is located.

[0074] Furthermore, when the at least two deflectable sections (the first deflectable section 32 and the second deflectable section 34) are simultaneously bent, the plane on which the central axes of the respective deflectable sections lie coincides. This allows the medical device 10 to arbitrarily deflect the deflectable sections on the plane on which the curved central axes of the at least two deflectable sections lie, thereby further improving blood vessel selectivity, engagement force with the blood vessel, or backup force.

[0075] Furthermore, the radii of curvature of the at least two deflectable portions (first deflectable portion 32, second deflectable portion 34) may be different from each other. This allows the medical device 10 to bend at least two points in the longitudinal direction of the tubular body 30 with different radii of curvature by operating the operating portion 20.

[0076] Furthermore, the directions in which at least two deflectable portions (first deflectable portion 32, second deflectable portion 34) are simultaneously bent are opposite to each other. This allows the medical device 10 to bend at least two points in the longitudinal axis direction of the tubular body 30 to the same side by operating the operating portion 20.

[0077] Furthermore, the deflectable portions (first deflectable portion 32, second deflectable portion 34) have higher rigidity when deformed into a predetermined curved shape than when the deflectable portions are in a straight state. This allows each deflectable portion to have high rigidity, allowing the surgeon to easily insert at least one of the deflectable portions (e.g., first deflectable portion 32) into a target blood vessel (e.g., left common carotid artery A3).

[0078] Second Embodiment 7 to 9, a medical device 100 according to a second embodiment of the present invention differs from the first embodiment only in that the first deflectable portion 32 and the second deflectable portion 34 are bent to the same side on the plane M by the same operation of the operation unit 20. That is, in the circumferential direction, the second inner soft portion 55 is located on the same side as the first inner soft portion 54, and the second inner hard portion 59 is located on the same side as the first inner hard portion 58. Furthermore, in the circumferential direction, the second outer soft portion 45 is located on the same side as the first outer soft portion 44, and the second outer hard portion 49 is located on the same side as the first outer hard portion 48.

[0079] Next, the operation of the medical device 100 according to the second embodiment will be described.

[0080] 9 , when the second operating unit 22 moves distally relative to the first operating unit 21, a compressive force acts on the outer tube 40 and a tensile force acts on the inner tube 50. As a result, the first deflectable portion 32 bends toward the side where the first outer soft portion 44 of the outer tube 40 is located and the first inner hard portion 58 of the inner tube 50 is located. At the same time, the second deflectable portion 34 bends toward the side where the second outer soft portion 45 of the outer tube 40 is located and the second inner hard portion 59 of the inner tube 50 is located. The radii of curvature of the first deflectable portion 32 and the second deflectable portion 34 can be changed as desired depending on the amount of movement of the second operating unit 22 or the first operating unit 21.

[0081] Furthermore, the radius of curvature in the first deflectable portion 32 is smaller or larger than the radius of curvature occurring in the second deflectable portion 34. Note that, in cases where the first deflectable portion 32 and the second deflectable portion 34 are separated from each other (where there is an intermediate portion 33), the radius of curvature occurring in the second deflectable portion 34 may be the same as the radius of curvature occurring in the first deflectable portion 32.

[0082] As described above, the directions in which at least two deflectable portions (first deflectable portion 32, second deflectable portion 34) are simultaneously bent are the same. This allows the medical device 100 to have at least two locations in the longitudinal axis direction of the tubular body 30 deflected to the same side by any operation of the operation unit 20.

[0083] <Third embodiment> 10, a medical device 200 according to a third embodiment of the present invention has three deflectable sections, and differs from the first embodiment in that the members forming each deflectable section are different half-split members before being joined together. That is, the first outer hard section 221, the second outer hard section 222, the third outer hard section 223, the first outer soft section 231, the second outer soft section 232, and the third outer soft section 233 of the outer tube 201 are formed from different half-split members.

[0084] In addition, the first outer intermediate portion 241 located between the first outer portion 211 and the second outer portion 212, and the second outer intermediate portion 242 located between the second outer portion 212 and the third outer portion 213 are formed as independent tubular members.

[0085] In addition, the first inner hard portion 261, the second inner hard portion 262, the third inner hard portion 263, the first inner soft portion 271, the second inner soft portion 272 and the third inner soft portion 273 of the inner tube 202 are formed from different half-split members.

[0086] In addition, the first inner intermediate portion 281 located between the first inner portion 251 and the second inner portion 252, and the second inner intermediate portion 282 located between the second inner portion 252 and the third inner portion 253 are formed as independent tubular members.

[0087] This allows the hardness of each portion of the medical device 200 according to the third embodiment to be set as desired. The medical device 200 according to the third embodiment can be deformed into a shape as shown in Fig. 11, for example, and has a first deflectable portion 203 formed by a first outer portion 211 and a first inner portion 251, a second deflectable portion 204 formed by a second outer portion 212 and a second inner portion 252, and a third deflectable portion 205 formed by a third outer portion 213 and a third inner portion 253.

[0088] 10-11, as an example of the third embodiment, the first outer soft portion 231 and the first inner soft portion 271 have a hardness of 25D, and the first outer hard portion 221 and the first inner hard portion 261 have a hardness of 90D. The second outer soft portion 232 and the second inner soft portion 272 have a hardness of 35D, and the second outer hard portion 222 and the second inner hard portion 262 have a hardness of 85D. The third outer soft portion 233 and the third inner soft portion 273 have a hardness of 55D, and the third outer hard portion 223 and the third inner hard portion 263 have a hardness of 75D. The first outer intermediate portion 241, the first inner intermediate portion 281, the second outer intermediate portion 242, and the second inner intermediate portion 282 have a hardness of 60D.

[0089] In this case, the difference in hardness between the soft portion and the hard portion is greatest in the first deflectable portion 203, next greatest in the second deflectable portion 204, and next greatest in the third deflectable portion 205. Note that the first outer intermediate portion 241, the first inner intermediate portion 281, the second outer intermediate portion 242, and the second inner intermediate portion 282 have uniform hardness in the circumferential direction. Therefore, as shown in FIG. 11 , by performing the same operation on the operation unit 20, the first deflectable portion 203 has the smallest radius of curvature R1, the second deflectable portion 204 has the next smallest radius of curvature R2, and the third deflectable portion 205 has the next smallest radius of curvature R3. In this way, the radius of curvature of the two deflectable portions is smaller when the difference in hardness between the outer soft portion and the outer hard portion is greater than when the difference in hardness between the outer soft portion and the outer hard portion is smaller. This makes it possible to set a desired radius of curvature by varying the difference in hardness between the soft and hard portions, particularly the difference in hardness between the outer soft and hard portions, and by setting the circumferential positions of the hard and soft portions and the lengths of each deflectable portion and each intermediate portion in addition to the radius of curvature, the shape after deformation can be freely designed.

[0090] The medical device 200 may be a catheter such as a COBRA (registered trademark) type shown in Fig. 12(A) or a JUDKINS LEFT (registered trademark) type shown in Fig. 12(B). In the first and second embodiments, the hardness of each portion may be set arbitrarily, as in the third embodiment.

[0091] The present invention is not limited to the above-described embodiments, and various modifications may be made by those skilled in the art within the technical spirit of the present invention. For example, the medical devices 10, 100, and 200 may be catheters for aspirating thrombi in the treatment of pulmonary embolism. Furthermore, the medical devices 10, 100, and 200 may be catheters for embolizing blood vessels that cause endoleaks or catheters used in fenestrated endovascular aortic repair.

[0092] Furthermore, when the at least two deflectable portions are bent, the planes on which the central axes of the respective deflectable portions lie may be different, thereby enabling the medical instrument to bend a range of the tubular body including the at least two deflectable portions into a three-dimensionally curved shape by operating the operating unit. [Explanation of symbols]

[0093] 10, 100, 200 Medical Equipment 20 Control section 30 Body 32, 203 First deflectable part (deflectable part) 33 Middle section 34, 204 Second deflectable part (deflectable part) 36 Fixed part 40, 201 outer tube 40A, 211 First outer part 40B, 212 2nd outer part 41 Outer tube body 42 First outer opening 43 Second outer opening 44, 231 First outer soft part 45, 232 Second outer soft part 48, 221 1st outer hard part 49, 222 2nd outer hard part 50, 202 inner tube 50A, 251 First inner part 50B, 252 2nd inner part 51 Inner pipe body 52 First inner opening 53 Second inner opening 54, 271 1st inner soft part 55, 272 2nd inner soft part 58, 261 1st inner hard part 59, 262 2nd inner hard part 205 Third deflectable part (deflectable part) 223 Third outer hard part 233 Third outer soft part 263 Third inner hard part 273 Third inner soft part

Claims

1. A medical instrument having a tubular body extending from an operating section located on a base end side to a tip end side, The medical device is characterized in that the tubular body has a plurality of deflectable portions that can be deformed into a predetermined curved shape by operating the operating portion and are arranged at different positions in the longitudinal direction of the tubular body.

2. the tubular body includes an outer tube and an inner tube, at least a portion of which is disposed inside the outer tube, fixed to the outer tube by a fixing portion distal to the deflectable portion, and slidable in the longitudinal direction relative to the outer tube on the proximal side of the fixing portion; each of the deflectable portions has an outer portion formed on the outer tube and an inner portion formed on the inner tube and positioned inside the outer portion; the outer portion has an outer hard portion formed in a part of the circumferential direction, and an outer soft portion formed at a position different from the outer hard portion in the circumferential direction and softer than the outer hard portion, the inner portion has an inner hard portion formed in a part of the circumferential direction, and an inner soft portion formed at a position different from the inner hard portion in the circumferential direction and softer than the outer hard portion, The medical device according to claim 1, wherein at least a portion of the inner soft portion is located inside the outer hard portion, and at least a portion of the inner hard portion is located inside the outer soft portion.

3. The medical instrument according to claim 1 or 2, wherein when at least two of the deflectable sections are bent simultaneously, the planes on which the central axes of the deflectable sections lie coincide with each other.

4. The medical device according to claim 3, wherein the directions in which the at least two deflectable portions simultaneously bend are the same direction.

5. The medical instrument according to claim 3 or 4, wherein the at least two deflectable portions have different radii of curvature.

6. The medical device according to claim 3 , wherein the directions in which the at least two deflectable portions simultaneously bend are opposite to each other.

7. The medical instrument according to claim 1 or 2, wherein the planes on which the central axes of the at least two deflectable portions lie when the deflectable portions are bent are different from each other.

8. 6. The medical device according to claim 5, wherein the radius of curvature of the at least two deflectable portions is smaller when the difference in hardness between the outer soft portion and the outer hard portion is larger than when the difference in hardness between the outer soft portion and the outer hard portion is smaller.

9. 3. The medical device according to claim 1, wherein the deflectable portion has a higher rigidity when deformed into the predetermined curved shape than when the deflectable portion is in a straight state.

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