Medical instrument

Abstract

Provided is a medical instrument with which it is possible to improve blood vessel selectivity, strength of engagement to a blood vessel, or backup power.　A medical instrument (10) has a tube body (30) extending to the distal-end side from an operation part (20) positioned on the base-end side, wherein: the tube body (30) has a shape-imparted part (32) to which a curved shape is imparted in advance, and at least one deflectable part (34) positioned closer to the base-end side than the shape-imparted part (32); and the deflectable part (34) can be deformed into a prescribed curved shape through an operation performed in the operation part (20).

Description

medical equipment

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

[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.

[0004] US Patent Application Publication No. 2017 / 080186

[0005] However, even with the medical device described in Patent Document 1, although it may be possible to reach the vicinity of the target site, it may be difficult to maintain the position of the distal end of the medical device. For example, a medical device inserted through the radial artery can be sharply curved within a large blood vessel such as the aortic arch to reach the entrance of the narrow common carotid artery, but it is difficult to insert it further distally in the curved state. However, if the curve is released, it may not engage with the entrance of the common carotid artery and may fall off.

[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.

[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) A 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, wherein the tubular body has a shape imparting section to which a curved shape has been imparted in advance, and at least one deflectable section located at the base end side of the shape imparting section, and the deflectable section can be deformed into a predetermined curved shape by operating the operating section.

[0009] The medical device described in (1) above can improve blood vessel selectivity, engagement force with the blood vessel, or backup force by deflecting the deflectable portion, so that the deflectable portion and the shape-imparting portion can be shaped to suit the blood vessel within the blood 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, the deflectable portion including an outer portion formed on the outer tube and an inner portion formed on the inner tube and located inside the outer portion, the outer portion including 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, the inner portion including 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, 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 the deflectable portion can be deflected so as to bend toward the side of the outer soft portion of the outer tube where the inner hard portion of the inner tube is located. Also, 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 the deflectable portion can be deflected so as to bend toward the side of the outer hard portion of the outer tube where the inner soft portion of the inner tube is located.

[0011] (3) In the medical device according to (1) or (2) above, when the deflectable portion is bent, a plane on which a central axis of the deflectable portion lies may coincide with a plane on which a curved central axis of the shape-imparting portion lies. This allows the medical device to arbitrarily deflect the deflectable portion on the plane on which the curved central axis of the shape-imparting portion lies, thereby further improving blood vessel selectivity, engagement force with a blood vessel, or backup force.

[0012] (4) In the medical device described in (2) above, the shape-imparting portion may be curved toward the side opposite to the side where the outer soft portion is located on the outer portion of the deflectable portion. As a result, when a compressive force acts on the outer tube and a tensile force acts on the inner tube, the deflectable portion deflects to bend toward the side where the outer soft portion of the outer tube is located, i.e., the side opposite to the side where the shape-imparting portion is curved. Furthermore, when a tensile force acts on the outer tube and a compressive force acts on the inner tube, the deflectable portion deflects to bend toward the side where the outer hard portion of the outer tube is located, i.e., the side where the shape-imparting portion is curved.

[0013] (5) In the medical device described in (2) above, the shape-imparting portion may be curved toward the side of the outer portion of the deflectable portion where the outer soft portion is located. Thus, when a compressive force acts on the outer tube and a tensile force acts on the inner tube, the deflectable portion deflects so as to bend toward the side of the outer soft portion of the outer tube, i.e., the side where the shape-imparting portion is curved. Furthermore, when a tensile force acts on the outer tube and a compressive force acts on the inner tube, the deflectable portion deflects so as to bend toward the side of the outer hard portion of the outer tube, i.e., the side opposite to the side where the shape-imparting portion is curved.

[0014] (6) In the medical device according to any one of (1) to (5) above, the tubular body may have a straight portion having a linear central axis between the shape-imparting portion and the deflectable portion closest to the distal end, thereby enabling the shape-imparting portion of the medical device located distally of the straight portion to be inserted deep into a target blood vessel.

[0015] (7) In the medical device according to any one of (1) to (6) above, the tubular body may have a plurality of the deflectable portions arranged at different positions in the longitudinal direction, thereby enabling the medical device to achieve a complexly curved shape, thereby enabling the deflectable portions and the shape-imparting portion to have more appropriate shapes, and further improving blood vessel selectivity, engagement force with blood vessels, or backup force.

[0016] (8) In the medical instrument according to any one of (1) to (7) above, the deflectable portion may have a rigidity higher than that of the shape-imparting portion when the deflectable portion is deformed into the predetermined curved shape. This allows the shape-imparting portion to be easily advanced to the peripheral side of the target blood vessel by the rigidity of the deflectable portion without damaging the target blood vessel with the shape-imparting portion.

[0017] (9) In the medical device according to any one of (1) to (8) above, the rigidity of the deflectable portion may be higher when deformed into the predetermined curved shape than when the deflectable portion is not subjected to a compressive or tensile force. This allows the medical device to easily insert the shape-imparting portion into a target blood vessel by utilizing the easily deformable property of the deflectable portion when not subjected to a compressive or tensile force. Furthermore, the medical device allows the deflected shape of the deflectable portion to be maintained and the state of engagement with the target blood vessel to be favorably maintained by utilizing the property of the deflectable portion that increases in rigidity when deformed into the predetermined curved shape.

[0018] 2A , 2B , 2C , 2D , 2E , 2F , 2G , 2H ... 10A and 10B are diagrams showing a medical device according to a second embodiment, where (A) is a plan view and (B) is a transverse cross-sectional view taken along line B-B in FIG. 10A. Plan views illustrating the operation of the medical device according to the second embodiment, where (A) shows a state in which the first operating unit has been moved distally relative to the second operating unit, and (B) shows a state in which the first operating unit has been moved proximally relative to the second operating unit. Plan views showing application examples of the medical device according to the second embodiment, where (A) shows a Cobra-type catheter and (B) shows a Judkins-Left-type catheter.

[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 device 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 accessed by an operator from the right radial artery or the left radial artery, and is then advanced to the right common carotid artery A4 or the left common carotid artery A3.

[0021] As shown in FIGS. 1 to 3, the medical instrument 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 its entire length. The tubular body 30 includes a shape imparting portion 32 located on the distal side, a straight portion 33 located closer to the base end than the shape imparting portion 32, one deflectable portion 34 located closer to the base end than the straight portion 33, and a base portion 35 located closer to the base end than the deflectable portion 34.

[0023] The tubular body 30 may have a flexible tip at its distal end to prevent damage to the contact object. 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 shape imparting portion 32 is given a shape curved in one direction in advance. The shape of the shape imparting portion 32 is not particularly limited. The length L1 of the shape imparting portion 32 in the major axis direction is, for example, 1 mm to 100 mm, preferably 5 mm to 30 mm, and as an example, 10 mm. The radius of curvature R1 of the shape imparting portion 32 is, for example, 1 mm to 100 mm, preferably 5 mm to 30 mm, and as an example, 10 mm. Furthermore, the shape imparting portion 32 may be curved three-dimensionally.

[0025] The deflectable portion 34 can be deflected so as to be curved in a predetermined direction by the surgeon's operation of the operation portion 20. The central axis of the deflectable portion 34 can be curved on a predetermined plane M.

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

[0027] The base 35 is a tubular portion that extends substantially linearly in the longitudinal direction between the deflectable portion 34 and the operation portion 20. The base 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 spirally, or a metal pipe in which at least one slit is formed.

[0028] At least a portion of the tube 30 proximal to the tip of the deflectable portion 34 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 tube 30 has a fixed portion 36, to which the inner tube 50 and the outer tube 40 are fixed, distal to the deflectable portion 34. That is, the portion of the tube 30 proximal to the fixed portion 36 is formed as a double-tube structure. The location of the fixed portion 36 is not particularly limited as long as it is distal to the deflectable portion 34 and does not impair the original function of the shape-imparting portion 32. For example, it may be located on the straight portion 33, the shape-imparting portion 32, or distal to the shape-imparting portion 32. The portions of the outer tube 40 and the inner tube 50 proximal to the fixed portion 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 portion 36 with a small clearance sufficient to allow sliding movement.

[0029] The outer tube 40 has a flexible outer tube body 41 with a partial outer opening 42 formed therein, an outer soft portion 43 disposed in the outer opening 42, and a long outer reinforcing member 44 formed from a material harder than the outer tube body 41.

[0030] The outer opening 42 is formed in a range in the longitudinal direction where the deflectable portion 34 of the outer tube main body 41 is located. The outer opening 42 is formed partially in the circumferential direction, for example, in a range of 1 to 359 degrees. The outer opening 42 is preferably formed in a range of 45 to 315 degrees, more preferably 90 to 270 degrees.

[0031] The outer tube body 41 has an outer hard portion 45 at a position in the circumferential direction different from the range where the outer opening 42 is formed, within the range where the deflectable portion 34 is located.

[0032] The outer soft portion 43 is disposed in connection with the outer opening 42. The outer soft portion 43 has a lower hardness than the outer hard portion 45 of the outer tube body 41. The hardness can be defined, for example, by durometer hardness or Rockwell hardness. As an example, the durometer hardness of the outer tube body 41 is 72D, and the durometer hardness of the outer soft portion 43 is 35D. The outer soft portion 43 and the outer hard portion 45 are aligned in the circumferential direction and form a single tubular outer portion 46.

[0033] The distal end of the outer reinforcing member 44 is located distally of the outer opening 42, and the proximal end of the outer reinforcing member 44 is located proximal to the outer opening 42. For example, the distal end of the outer reinforcing member 44 may be located at the distal end of the outer tube main body 41, or may be located proximal to the distal end of the outer tube main body 41 as long as it is distal to the outer opening 42. The proximal end of the outer reinforcing member 44 may be located proximal to the outer tube main body 41, or may be distal to the proximal end of the outer tube main body 41 as long as it is proximal to the outer opening 42. The outer reinforcing member 44 is disposed at a specific circumferential position of the outer tube main body 41, extending parallel to the longitudinal axis. In this embodiment, the outer reinforcing member 44 is disposed embedded in the outer hard portion 45. The outer reinforcing member 44 may be disposed so as to contact the outer surface of the outer hard portion 45 without being embedded in the outer hard portion 45. The outer reinforcing member 44 is formed from, for example, a resin material such as Kevlar (registered trademark), glass fiber, carbon fiber, or a metal material such as stainless steel.

[0034] The inner tube 50 has a flexible inner tube body 51 with a partial inner opening 52 formed therein, an inner soft portion 53 disposed in the opening, and a long inner reinforcing member 54 formed from a material harder than the inner tube body 51.

[0035] The inner opening 52 is formed in a range in the longitudinal direction where the deflectable portion 34 of the inner pipe main body 51 is located. The inner opening 52 is formed partially in the circumferential direction, for example, in a range of 1 to 359 degrees. The inner opening 52 is preferably formed in a range of 45 to 315 degrees, more preferably 90 to 270 degrees.

[0036] The inner pipe body 51 has an inner hard portion 55 at a position in the circumferential direction different from the range where the inner opening 52 is formed, within the range where the deflectable portion 34 is located.

[0037] The inner soft portion 53 is disposed so as to be connected to the inner opening 52. The inner soft portion 53 has a lower hardness than the inner hard portion 55 of the inner pipe main body 51. The inner soft portion 53 and the inner hard portion 55 are aligned in the circumferential direction and form a single tubular inner portion 56.

[0038] The tip of the inner reinforcing member 54 is located distally of the inner opening 52, and the base end of the reinforcing member is located proximal to the inner opening 52. For example, the tip of the inner reinforcing member 54 may be located at the tip of the inner pipe main body 51, but may be located proximal to the tip of the inner pipe main body 51 as long as it is distal to the inner opening 52. The base end of the inner reinforcing member 54 may be located proximal to the inner pipe main body 51, but may be distal to the base end of the inner pipe main body 51 as long as it is proximal to the inner opening 52. The inner reinforcing member 54 is disposed at a specific circumferential position of the inner pipe main body 51, extending parallel to the longitudinal direction. In this embodiment, the inner reinforcing member 54 is disposed embedded in the inner hard portion 55. Note that the inner reinforcing member 54 may not be embedded in the inner hard portion 55, but may be disposed so as to contact the outer surface of the inner hard portion 55. The inner reinforcing member 54 is formed of a material that can be used for the outer reinforcing member 44 described above.

[0039] The outer portion 46 of the outer tube 40 and the inner portion 56 of the inner tube 50 form one deflectable portion 34 of the tube body 30. The deflectable portion 34 is a portion that can be deflected to bend in a predetermined direction. At least a portion of the inner soft portion 53 is located inside the outer hard portion 45. At least a portion of the inner hard portion 55 is located inside the outer soft portion 43. In the circumferential direction, the inner soft portion 53 is located on the opposite side of the outer soft portion 43, and the inner hard portion 55 is located on the opposite side of the outer hard portion 45.

[0040] The outer soft portion 43, the outer hard portion 45, the inner soft portion 53, and the inner hard portion 55 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.

[0041] In this embodiment, the central axis of the tube body 30, the central axis of the outer reinforcing member 44, and the central axis of the inner reinforcing member 54 lie on plane M, and the deflectable portion 34 has a structure that is plane-symmetrical with respect to plane M. The shape-imparting portion 32 also bends on the same plane M. The outer soft portion 43 of the outer tube 40 is located on the side of cross section M where the shape-imparting portion 32 bends.

[0042] In this embodiment, when the deflectable portion 34 is deformed into a predetermined curved shape by operating the first operating portion 21 and the second operating portion 22 described below, the rigidity of the deflectable portion 34 is higher than the rigidity of the shape imparting portion 32.

[0043] The rigidity of the deflectable portion 34 when deformed into the above-described predetermined curved shape is higher than the rigidity of the deflectable portion 34 when the first operating portion 21 and the second operating portion 22 are not operated and no compressive or tensile force is applied to the deflectable portion 34. When the first operating portion 21 and the second operating portion 22 are not operated and no compressive or tensile force is applied to the deflectable portion 34, the rigidity of the deflectable portion 34 is equal to or lower than the rigidity of the shape imparting portion 32.

[0044] Note that the specified curved shape is the desired shape that appears when the operating unit 20 is operated, and does not include the shape that appears between the initial positions of the first operating unit 21 and the second operating unit 2 in this embodiment and the position where the desired shape is obtained.

[0045] The operation unit 20 has a first operation unit 21 fixed to the proximal end of the inner tube 50 and a second operation unit 22 fixed to the proximal end of the outer tube 40. The first operation unit 21 has a proximal 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 the inner tube 50.

[0046] Next, the operation of the medical device 10 according to the first embodiment will be described.

[0047] 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 distal end and the distal end is pushed toward the base end), the softer portion contracts more in the longitudinal direction than the harder portion, shortening and bending toward the side where the softer portion is located. 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 proximal end and the distal end is pulled toward the distal end), the softer portion stretches more in the longitudinal direction than the harder portion, lengthening and bending toward the side where the harder portion is located.

[0048] 4A , 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 deflectable portion 34 bends toward the side of the inner hard portion 55 of the inner tube 50, which is opposite the side of the outer soft portion 43 of the outer tube 40. That is, the deflectable portion 34 bends on the plane M in the direction opposite to the side where the shape imparting portion 32 is bent. As a result, the distal end of the medical instrument 10 deforms into a Simmons (registered trademark) shape. The radius of curvature of the deflectable portion 34 can be arbitrarily changed depending on the amount of movement of the second operating unit 22 or the first operating unit 21.

[0049] 4(B) , when the second operating part 22 moves in the proximal direction relative to the first operating part 21, a tensile force acts on the outer tube 40 and a contracting force acts on the inner tube 50. This causes the deflectable part 34 to bend toward the side where the outer hard part 45 of the outer tube 40 is located and the inner soft part 53 of the inner tube 50 is located. In other words, the deflectable part 34 bends on the plane M toward the side where the shape-imparting part 32 is bent.

[0050] 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.

[0051] 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. As shown by the dashed line in Figure 5, the surgeon brings the medical device 10 from the right subclavian artery A1 to the aortic arch A2.

[0052] Next, as shown in Figure 4 (A), the surgeon moves the second operating unit 22 toward the distal end relative to the first operating unit 21. As a result, a compressive force acts on the outer tube 40, and a tensile force acts on the inner tube 50.

[0053] When a compressive force acts on the outer tube 40 and a tensile force acts on the inner tube 50, the deflectable portion 34 bends toward the side of the outer soft portion 43 of the outer tube 40 and the side of the inner hard portion 55 of the inner tube 50. In other words, the deflectable portion 34 bends on the plane M toward the side opposite to the side where the shape-imparting portion 32 is bent. As a result, the distal end of the medical device 10 is deformed into a shape similar 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 vessel.

[0054] Next, the surgeon inserts the shaping portion 32 of the medical device 10 into the left common carotid artery A3, as shown in Fig. 5. The surgeon can easily insert the shaping portion 32 from the aortic arch A2 into the left common carotid artery A3 by utilizing the deflectable portion 34, which is bent by more than 90 degrees in the opposite direction to the shaping portion 32.

[0055] Next, the surgeon advances the shaping portion 32 toward the distal end of the left common carotid artery A3. Because the deflectable portion 34, once deformed into a predetermined shape, is more rigid than the shaping portion 32, the shaping portion 32 does not damage the left common carotid artery A3, and the rigidity of the deflectable portion 34 allows the shaping portion 32 to be easily advanced toward the distal end of the blood vessel. The surgeon then engages the shaping portion 32 at a predetermined position on the distal end of the left common carotid artery A3. Because the shaping portion 32 has a curved shape, it maintains contact with the left common carotid artery A3 and generates a high backup force when other medical instruments are advanced and manipulated or contrast medium is injected deep into the left common carotid artery A3 via the medical device 10. Because the medical device 10 has a straight portion 33 between the shaping portion 32 and the deflectable portion 34, the shaping 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 part 21 and the second operating part 22, activating the locking mechanism can maintain the shape of the deflected deflectable part 34 and maintain the state of engagement with the left common carotid artery A3 in a good condition.

[0056] When the surgeon removes the medical instrument 10, the surgeon returns the positional relationship between the first operating unit 21 and the second operating unit 22 to the original position. This causes the deflectable portion 34 to return to its original linear shape, as shown in Figure 1. This allows the surgeon to easily remove the medical instrument 10.

[0057] 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 aspirates 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 femoral 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 deflectable portion 34 bends on the plane M toward the side opposite to the bending side of the shape-imparting portion 32. The portion of the tubular body 30 proximal to the deflectable portion 34 remains substantially straight and in contact with the inner wall of the inferior vena cava A5, maintaining its position, or generating 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. The opening at the tip of the tubular body 30 faces the tip and is located approximately at the center of the inferior vena cava A5. 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, because the medical device 10 has the curved shape-imparting portion 32, it can retrieve the thrombus C caught on the side surface of the inferior vena cava filter 60 even when the deflectable portion 34 is not deflected.

[0058] Next, as shown in FIG. 7 , 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 embolizing a target blood vessel E (e.g., the inferior mesenteric artery) that is causing an endoleak in an aortic aneurysm D. The surgeon inserts the medical device 10 through the iliac artery in the groin and reaches the lesion where the aortic aneurysm D has formed. 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 deflectable portion 34 bends on the plane M toward the side opposite to the bending side of the shaping portion 32. Because the distal end of the tubular body 30 faces laterally, the surgeon can bring the shaping portion 32 into contact with the inner wall of the target blood vessel E, as shown in FIG. 7 . Therefore, the shape-imparting portion 32 maintains its position by contacting the inner wall of the target blood vessel E, or generates a strong backup force when another medical instrument is advanced into the target blood vessel E via the medical instrument 10 to operate it or to inject a contrast agent. Because the surgeon can freely adjust the radius of curvature of the deflectable portion 34, the surgeon can easily select the target blood vessel E by giving the deflectable portion 34 an appropriate shape. The surgeon can insert the tip of the tubular body 30 deep into the target blood vessel E and release embolic material into the target blood vessel E.

[0059] 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 to be inserted into a target blood vessel E (e.g., a renal artery) connected to an aortic aneurysm D in which a fenestrated stent graft 70 has been placed, as shown in FIG. 8 . The surgeon inserts the medical device 10 through the iliac artery in the groin and reaches the fenestrated stent graft 70 placed in the aortic aneurysm D. Next, the surgeon moves the second operating unit 22 distally 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 deflectable portion 34 bends on the plane M to the side opposite to the bending side of the shaping portion 32. Because the distal end of the tubular body 30 faces laterally, the surgeon can pass the shaping portion 32 through the fenestration 71 of the fenestrated stent graft 70 and bring it into contact with the inner wall of the target blood vessel E, as shown in FIG. 8(A) . Furthermore, as shown in FIG. 8(B) , the surgeon can advance the shaping portion 32 to the periphery of the target blood vessel E through the fenestration 71 of the fenestrated stent graft 70. As a result, the shaping portion 32 contacts the inner wall of the target blood vessel E to maintain its position, or generates a high backup force when advancing another medical instrument into the target blood vessel E via the medical instrument 10 to manipulate it or inject a contrast agent. Because the surgeon can arbitrarily adjust the radius of curvature of the deflectable portion 34, the surgeon can easily select the fenestration 71 and the target blood vessel E by appropriately shaping the deflectable portion 34. The surgeon can insert the distal end of the tubular body 30 deep into the target blood vessel E and place the graft in the target blood vessel E.

[0060] As described above, the medical instrument 10 according to the first embodiment is a medical instrument 10 having a tubular body 30 extending from an operating unit 20 located on the proximal end side to the distal end side, and the tubular body 30 has a shape-imparting portion 32 to which a curved shape has been imparted in advance, and at least one deflectable portion 34 located on the proximal end side of the shape-imparting portion 32, and the deflectable portion 34 can be deformed into a predetermined curved shape by operating the operating unit 20. As a result, by deflecting the deflectable portion 34, the medical instrument 10 can shape the deflectable portion 34 and the shape-imparting portion 32 inside the blood vessel to suit the blood vessel, thereby improving blood vessel selectivity, engagement force with the blood vessel, or backup force.

[0061] 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 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, the deflectable portion 34 having an outer portion 46 formed on the outer tube 40 and an inner portion 56 formed on the inner tube 50 and located inside the outer portion 46, the outer portion 46 having an outer hard portion 45 formed in a portion of the circumferential direction and a circumferential hard portion 46 formed on the outer tube 40. The inner portion 56 has an inner hard portion 55 formed in a part of the circumferential direction and an inner soft portion 53 formed in a position different from the inner hard portion 55 in the circumferential direction and softer than the outer hard portion 45, at least a part of the inner soft portion 53 being located inside the outer hard portion 45, and at least a part of the inner hard portion 55 being located inside the outer soft portion 43. 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 the deflectable portion 34 can be deflected so as to bend toward the side of the outer soft portion 43 of the outer tube 40 where the outer hard portion 43 is located and toward the side of the inner hard portion 55 of the inner tube 50 where the inner hard portion 55 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 the deflectable portion 34 can be deflected so as to bend toward the side where the outer hard portion 45 of the outer tube 40 is located and the inner soft portion 53 of the inner tube 50 is located.

[0062] Furthermore, when the deflectable portion 34 is bent, the plane on which the central axis of the deflectable portion 34 is located coincides with the plane on which the curved central axis of the shape-imparting portion 32 is located. This allows the medical device 10 to arbitrarily deflect the deflectable portion 34 on the plane on which the curved central axis of the shape-imparting portion 32 is located, thereby further improving blood vessel selectivity, engagement force with blood vessels, or backup force.

[0063] Furthermore, the shape-imparting portion 32 is curved toward the side opposite to the side where the outer soft portion 43 is disposed at the outer portion 46 of the deflectable portion 34. As a result, when a compressive force acts on the outer tube 40 and a tensile force acts on the inner tube 50, the deflectable portion 34 deflects so as to bend toward the side where the outer soft portion 43 of the outer tube 40 is located, i.e., the side opposite to the side where the shape-imparting portion 32 is curved. Furthermore, when a tensile force acts on the outer tube 40 and a compressive force acts on the inner tube 50, the deflectable portion 34 deflects so as to bend toward the side where the outer hard portion 45 of the outer tube 40 is located, i.e., the side where the shape-imparting portion 32 is curved.

[0064] The tubular body 30 also has a straight portion 33 having a linear central axis between the shape-imparting portion 32 and the deflectable portion 34 located at the most distal end. This allows the medical device 10 to insert the shape-imparting portion 32, which is located distally of the straight portion 33, deep into the target blood vessel E.

[0065] Furthermore, when the deflectable portion 34 is deformed into a predetermined curved shape, the rigidity of the deflectable portion 34 is higher than the rigidity of the shape-imparting portion 32. As a result, the medical device 10 can easily advance the shape-imparting portion 32 to the peripheral side of the target blood vessel (e.g., the left common carotid artery A3) without damaging the target blood vessel (e.g., the left common carotid artery A3) with the shape-imparting portion 32 due to the rigidity of the deflectable portion 34.

[0066] Furthermore, the rigidity of the deflectable portion 34 is higher when it is deformed into a predetermined curved shape than when it is not subjected to a compressive or tensile force. This allows the medical device 10 to easily insert the shape-imparting portion 32 into a target blood vessel (e.g., the left common carotid artery A3) by utilizing the easily deformable property of the deflectable portion 34 when it is not subjected to a compressive or tensile force. Furthermore, the medical device 10 can maintain the shape of the deflectable portion 34 after deflection and effectively maintain engagement with the target blood vessel (e.g., the left common carotid artery A3) by utilizing the property of the deflectable portion 34 that increases in rigidity when it is deformed into a predetermined curved shape.

[0067] 9, a medical device 100 according to a second embodiment of the present invention differs from the first embodiment only in that the side on the cross section M where the shape-imparting portion 32 is bent is opposite to that in the first embodiment. Therefore, the outer soft portion 43 of the outer tube 40 and the inner hard portion 55 of the inner tube 50 are located on the side on the cross section M where the shape-imparting portion 32 is bent, and the outer hard portion 45 of the outer tube 40 and the inner soft portion 53 of the inner tube 50 are located on the opposite side.

[0068] Next, the operation of the medical device 100 according to the second embodiment will be described.

[0069] 10(A), 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 deflectable portion 34 bends toward the side where the outer soft portion 43 of the outer tube 40 is located and the inner hard portion 55 of the inner tube 50 is located. In other words, the deflectable portion 34 bends on the plane M toward the side where the shape imparting portion 32 is bent. The radius of curvature of the deflectable portion 34 can be arbitrarily changed depending on the amount of movement of the second operating unit 22 or the first operating unit 21.

[0070] 10(B) , when the second operating part 22 moves in the proximal direction relative to the first operating part 21, a tensile force acts on the outer tube 40 and a contracting force acts on the inner tube 50. This causes the deflectable part 34 to bend toward the side where the outer hard part 45 of the outer tube 40 is located and the inner soft part 53 of the inner tube 50 is located. In other words, the deflectable part 34 bends on the plane M to the side opposite to the side where the shape-imparting part 32 is bent.

[0071] Next, an example in which the structure of the medical device 100 according to the second embodiment is applied to a catheter will be described. The medical device 100 shown in Fig. 11(A) is a COBRA (registered trademark) type catheter.

[0072] The cobra-shaped medical instrument 100 has a deflectable portion 34 located proximal to the shape-imparting portion 32 and capable of deflecting approximately 90 degrees toward the side to which the shape-imparting portion 32 is bent, and a bending portion 101 located proximal to the deflectable portion 34 and bent toward the opposite side to the side to which the shape-imparting portion 32 is bent. The bending portion 101 is pre-shaped. Note that the bending portion 101 may be a second deflectable portion that deflects in the opposite direction to the deflectable portion 34 upon operation of the operation unit 20. The structure of the second deflectable portion is similar to the structure of the deflectable portion 34 of the first embodiment, and an outer hard portion 45 and an inner soft portion 53 are arranged on the side to which the shape-imparting portion 32 is bent.

[0073] The tube 30 may also have multiple deflectable sections 34 at different positions in the longitudinal direction. The number of deflectable sections 34 may be three or more. The deflection directions of the deflectable sections 34 may be the same or different, and can be set as appropriate.

[0074] The medical device 100 shown in FIG. 11(B) is a Judkins Left (registered trademark) type catheter. The Judkins Left type medical device 100 has a deflectable portion 34 located proximally of the shaping portion 32 and capable of deflecting more than 90 degrees toward the side to which the shaping portion 32 is bent. Judkins Left type catheters are used, for example, for prostatic artery embolization. When the medical device 100 is used for prostatic artery embolization, the shaping portion 32 contacts the inner wall of the prostatic artery. Therefore, the shaping portion 32 maintains its position by contacting the inner wall of the prostatic artery or generates a high backup force. The radius of curvature of the deflectable portion 34 can be adjusted arbitrarily, allowing for an appropriate shape to be formed and for easy selection of the prostatic artery. The shape of the tip of the medical device 100 used in prostatic artery embolization may be TIGER (registered trademark), JACKY (registered trademark), or SARAH (registered trademark).

[0075] As described above, the shape-imparting portion 32 of the medical device 100 according to the second embodiment is curved at the outer portion 46 of the deflectable portion 34 toward the side where the outer soft portion 43 is located. As a result, when a compressive force acts on the outer tube 40 and a tensile force acts on the inner tube 50, the deflectable portion 34 deflects so as to bend toward the side where the outer soft portion 43 of the outer tube 40 is located, i.e., the side where the shape-imparting portion 32 is curved. Furthermore, when a tensile force acts on the outer tube 40 and a compressive force acts on the inner tube 50, the deflectable portion 34 deflects so as to bend toward the side where the outer hard portion 45 of the outer tube 40 is located, i.e., the side opposite to the side where the shape-imparting portion 32 is curved.

[0076] The tubular body 30 may also have a plurality of deflectable portions 34 arranged at different positions in the longitudinal direction, which allows the medical device 100 to achieve a complexly curved shape, allowing the deflectable portions 34 and the shape-imparting portion 32 to have more appropriate shapes, thereby further improving blood vessel selectivity, engagement force with the blood vessel, or backup force.

[0077] The present invention is not limited to the above-described embodiment, and various modifications may be made by those skilled in the art within the technical spirit of the present invention. For example, the medical device 100 may be a catheter for aspirating thrombi in the treatment of pulmonary embolism.

[0078] This application is based on Japanese Patent Application No. 2024-82485 filed on May 21, 2024, the disclosures of which are incorporated herein by reference in their entirety.

[0079] DESCRIPTION OF SYMBOLS 10, 100 Medical instrument 20 Operation part 30 Tube 32 Shape imparting part 33 Straight part 34 Deflectable part 36 Fixed part 40 Outer tube 42 Outer opening 43 Outer soft part 45 Outer hard part 46 Outer part 50 Inner tube 52 Inner opening 53 Inner soft part 55 Inner hard part 56 inner part

Claims

1. A medical device having a tubular body extending from an operating section located on the base end side to the tip end side, wherein the tubular body has a shaping section that has been given a pre-curved shape, and at least one deflectable section located on the base end side of the shaping section, and the deflectable section can be deformed into a predetermined curved shape by operating the operating section.

2. The medical device according to claim 1, wherein the tubular body comprises 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, the deflectable portion comprising an outer portion formed on the outer tube and an inner portion formed on the inner tube and located inside the outer portion, the outer portion comprising an outer hard portion formed on a portion of the circumference 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 comprising an inner hard portion formed on a portion of the circumference 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, 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. A medical device as described in claim 1 or 2, characterized in that the plane in which the central axis of the deflectable portion lies when the deflectable portion is bent coincides with the plane in which the curved central axis of the shape-imparting portion lies.

4. The medical device according to claim 2, wherein the shape-imparting portion is curved toward the side opposite to the side on which the outer soft portion is disposed on the outer portion of the deflectable portion.

5. The medical device according to claim 2, wherein the shape-imparting portion is curved toward the side of the outer soft portion on the outer side of the deflectable portion.

6. A medical device according to claim 1 or 2, characterized in that the tubular body has a straight portion having a straight central axis between the shaping portion and the deflectable portion at the most distal end.

7. The medical device according to claim 1 or 2, wherein the tubular body has a plurality of the deflectable portions arranged at different positions in the longitudinal direction.

8. The medical device according to claim 1 or 2, wherein the rigidity of the deflectable portion is higher than the rigidity of the shape-imparting portion when the deflectable portion is deformed into the predetermined curved shape.

9. A medical device as described in claim 1 or 2, characterized in that the rigidity of the deflectable portion when deformed into the predetermined curved shape is higher than when the deflectable portion is not subjected to any compressive or tensile force.

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