Medical device

Abstract

A medical device (1) is provided with a basket (30) having a plurality of wires (20), a connecting member (80) positioned more to the proximal side than the basket (30), and a basket pusher (40) positioned more to the proximal side than the connecting member (80), in which the connecting member (80) includes a distal-side member (81) and a proximal-side member (82), and the distal-side member (81) is formed rotatably with respect to the proximal-side member (82).

Description

medical devices

[0001] The present invention relates to a medical device for use in a body lumen such as a blood vessel.

[0002] Endovascular treatment is one of the treatments for vascular lesions such as head and neck aneurysms, arteriovenous malformations, arteriovenous fistulas, pulmonary vascular malformations, renal vascular malformations, renal artery aneurysms, abdominal aneurysms, etc. As an endovascular treatment, for example, embolization is used, in which an embolic device having an embolization coil is placed at a target site, such as inside an aneurysm, to promote thrombosis and prevent the aneurysm from rupturing.

[0003] When the opening of an aneurysm or other vessel wall is large, the embolization coil placed inside the aneurysm may escape from the aneurysm. To prevent the coil from escaping, a device may be placed inside the aneurysm or in the blood vessel near the opening of the aneurysm. Another known embolization technique involves placing a basket inside the aneurysm and filling it with coils to retain the coils inside the aneurysm and prevent the aneurysm from rupturing.

[0004] For example, Patent Document 1 describes a device for treating an aneurysm that is located within a parent blood vessel defining a lumen and has a neck and an inner wall that define an inner cavity that communicates with the lumen, the device being configured to be deployed within the lumen and further comprising a foldable member that is adjusted to span the neck of the aneurysm and contact the inner wall when the device is deployed. Patent Document 2 describes a device including a self-expanding elastic permeable shell comprising a plurality of elongated elastic filaments with a woven structure secured to one another at their proximal and distal ends, a radially constrained elongated state configured for delivery within a microcatheter, whereby the thin woven filaments extend longitudinally from the proximal end to the distal end radially adjacent to one another along the length of the filament, and an expanded relaxed state having a spherical longitudinally shortened configuration relative to the radially constrained state, whereby the woven filaments form the self-expanding elastic permeable shell in a smooth path radially expanded from the longitudinal axis between the proximal and distal ends, the shell including a plurality of openings formed between the woven filaments, the largest of which is configured to allow blood flow through the opening at a velocity below the critical thrombosis velocity. Patent Document 3 describes an occlusion device comprising: a substantially tubular structure having a proximal end region and a distal end region, a first expanded state and a second collapsed state, and having dimensions suitable for insertion through the neck of an aneurysm via a patient's vascular system in the second collapsed state, an outer surface capable of contacting the aneurysm in the expanded state, and an inner surface; and a control ring disposed in the proximal end region of the structure, having a substantially annular body at least substantially surrounding the proximal end region to prevent radial expansion of the proximal end region and to provide an engagement feature during operation of the occlusion device.Patent document 4 describes an occlusion device that includes a catheter having a holding portion formed from a plurality of wires braided into a cylindrical shape with a closed proximal end, the closed proximal end having a first opening and a tip that is detachably connected to the holding portion, the catheter having a passage that extends to the distal end of the catheter and is aligned with the first opening of the holding portion, and embolic material in the passage of the catheter can be advanced through the passage, through the first opening, and into the cylindrical shape of the holding portion. Patent document 5 describes a device including a self-expanding permeable shell having a proximal end, a distal end, and a longitudinal axis, the shell including a plurality of elongated elastic filaments having a braided structure, the filaments being fastened at at least one of the proximal end or the distal end of the permeable shell, the permeable shell being configured to be delivered within a microcatheter and being in a radially constrained and extended state, and being in an expanded state having an axially shortened configuration relative to the radially constrained state, the permeable shell having a plurality of openings formed between the braided filaments; and the permeable shell in its expanded state including a plurality of lobes aligned circumferentially. Patent document 6 describes a device comprising an implant that is movable from a folded state to an expanded state, the implant comprising a proximal end, a distal end, and a braided section that forms a substantially continuous braided structure between the proximal end and the distal end, wherein in the expanded state, the implant comprises an outer occlusion bag extending from the proximal end of the implant and capable of occluding the aneurysm neck, an inner occlusion bag extending from the distal end of the implant and forming a groove in the outer occlusion bag, and a folded portion in the braided section positioned between the outer occlusion bag and the inner occlusion bag.

[0005] JP-A-2001-518320 JP-A-2011-519632 JP-A-2015-196092 JP-A-2019-506230 JP-A-2020-509922 JP-A-2020-58808

[0006] In the devices described in Patent Documents 1 to 6, the opening through which a long medical object such as a coil can be inserted is limited. Therefore, depending on the condition of the lesion and the procedure, it can be difficult to insert the long medical object into the device. In order to make it easier to insert the long medical object into the devices described in Patent Documents 1 to 6, the size of the device itself becomes large, which is a problem, and there is room for improvement.

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a medical device that allows an elongated medical object to be easily inserted into the basket.

[0008] The medical devices that solve the above-mentioned problems are as follows: [1] A medical device comprising: a basket having a plurality of wires; a connecting member disposed proximally of the basket; and a basket pusher disposed proximally of the connecting member, wherein the connecting member includes a distal member and a proximal member, and the distal member is formed to be rotatable relative to the proximal member. [2] The medical device described in [1], which has an outer tube having a distal end and a proximal end, wherein the basket is disposed in the lumen of the outer tube and is expandable when it comes out of the outer tube. [3] The medical device described in [1] or [2], wherein the connecting member is separable, and wherein the basket is detachable from the basket pusher. [4] The medical device described in any of [1] to [3], wherein one of the distal member and the proximal member has a spherical portion, and the other of the distal member and the proximal member has a covering portion that covers the spherical portion. [5] The medical device according to any one of [1] to [3], wherein the connecting member has an axial member proximal to the distal member and distal to the proximal member, and the axial member is inserted through the distal member and the proximal member. [6] The medical device according to any one of [1] to [5], wherein at least one of the material constituting the distal member and the material constituting the proximal member is metal. [7] The medical device according to any one of [1] to [6], wherein, when the distal member is rotated relative to the proximal member, the angle formed proximally between the extending direction of the basket pusher and a line passing through the distal end and the proximal end of the basket is 45 degrees or more and 150 degrees or less. [8] The basket comprises a first bundling portion at its distal portion that bundles and secures the plurality of wires, and a second bundling portion at its proximal portion that bundles and secures the plurality of wires, and the first bundling portion and the second bundling portion contain an X-ray opaque material. A medical device described in any of [1] to [7].

[0009] According to the medical device of the present invention, the connecting member includes a distal member and a proximal member, and the distal member is formed to be rotatable relative to the proximal member. This allows the distal member and the proximal member to rotate, bending the connecting member and tilting the basket connected to the basket pusher via the connecting member relative to the basket pusher. Therefore, for example, when the basket is placed inside the aneurysm after passing through the aneurysm opening, the side surface of the basket can face the aneurysm opening. Because the gaps between the wires of the basket tend to be larger at the side surface of the basket than at the proximal and distal ends, it is easier to insert a long medical object, such as a coil, into the basket through the gaps between the wires.

[0010] Fig. 1 shows a cross-sectional view parallel to the extension direction of a basket pusher at the distal end of a medical device in one embodiment of the present invention. Fig. 2 shows an enlarged view of a portion of the medical device shown in Fig. 1 where a connecting member is present. Fig. 3 shows a cross-sectional view parallel to the extension direction of a basket pusher in the medical device shown in Fig. 1 when the basket is housed in an outer tube. Fig. 4 shows an enlarged view of a portion of a medical device in another embodiment of the present invention where a connecting member is present.

[0011] The present invention will be described in more detail below based on the following embodiments. However, the present invention is not limited to the following embodiments, and can be implemented with appropriate modifications within the scope of the above and below-described purposes, and all such modifications are included within the technical scope of the present invention. For convenience, hatching and component symbols may be omitted in the drawings. In such cases, reference should be made to the specification and other drawings. The dimensions of various components in the drawings may differ from their actual dimensions, as priority is given to helping understand the features of the present invention.

[0012] FIG. 1 is a cross-sectional view parallel to the extension direction of the basket pusher 40 at the distal end of a medical device 1 according to an embodiment of the present invention, and FIG. 2 is an enlarged view of a portion of the medical device 1 where a connecting member 80 is located. In the present invention, the proximal side refers to the side closer to the user in the extension direction of the basket pusher 40, and the distal side refers to the side opposite the proximal side, i.e., the side where treatment is performed by the medical device 1 (the side of the lesion). The extension direction of the basket pusher 40 may also be referred to as the longitudinal axis direction. The longitudinal axis direction of the basket pusher 40 can also be referred to as the direction of approach to the basket pusher 40. Note that in FIGS. 1 and 2, the right side of the figure is the proximal side, and the left side of the figure is the distal side. Furthermore, in FIGS. 1 and 2, only some of the multiple wires 20 of the basket 30 are illustrated, and the other wires are omitted, to facilitate understanding of the relative positions of the various components and parts.

[0013] As shown in Figures 1 and 2, the medical device 1 of the present invention has a basket 30 having a plurality of wires 20, a connecting member 80 arranged proximally of the basket 30, and a basket pusher 40 arranged proximally of the connecting member 80, and the connecting member 80 includes a distal member 81 and a proximal member 82, and the distal member 81 is formed to be rotatable relative to the proximal member 82.

[0014] The medical device 1 can be used in embolization, which involves placing a basket 30 in a vascular lesion such as an aneurysm to promote thrombosis and prevent the aneurysm from rupturing. In embolization, the basket 30 is placed, for example, within an aneurysm at the terminal end of a biological lumen, within an aneurysm in the side wall of a biological lumen, or within the peripheral portion of a main duct of a biological lumen, and an elongated medical object is placed inside the basket 30 placed within the aneurysm or the peripheral portion of the main duct to promote thrombosis of the aneurysm. Examples of the elongated medical object include coils, wires, and string-like objects. Furthermore, the elongated medical object may be a tube for transporting elongated objects such as coils. Additionally, the tubular elongated medical object may be used to transport semi-solid fluids, gels, semi-solids, liquids, or even bag-like objects into the aneurysm. The liquid in the tubular elongated medical object may be, for example, a hardening liquid or a precipitating liquid.

[0015] As shown in Figures 1 and 2, the basket 30 has a plurality of wires 20. The basket 30 is expandable and contractible. Specifically, the basket 30 contracts to a reduced diameter when subjected to an external force, and expands to an increased diameter when not subjected to an external force. When the basket 30 is placed inside the aneurysm, the basket 30 comes into contact with the aneurysm wall and is subjected to external force from the aneurysm, causing it to deform.

[0016] The material constituting the wire 20 is preferably elastic, and examples thereof include metal wires such as single wires, flat wires, double wires, composite material wires, or stranded wires made of stainless steel such as SUS304 and SUS316, platinum, nickel, cobalt, chromium, titanium, tungsten, aluminum, gold, silver, Ni-Ti alloys, Co-Cr alloys, etc. Among these, the material constituting the wire 20 is preferably a superelastic material, and more preferably a Ni-Ti alloy metal wire. Using a Ni-Ti alloy metal wire as the material constituting the wire 20 increases the elasticity of the wire 20, which allows the basket 30 to return to its original shape even if the basket 30 is significantly deformed after being released from the outer tube 10, making it less likely to lose its shape.

[0017] The basket 30 may have a plurality of wires 20, and the number of wires 20 can be selected depending on the inner diameter of the lumen in the body, etc. In the drawings, the number of wires 20 in the basket 30 is limited. However, in an embodiment of the present invention, the basket 30 may be configured, for example, from 8 to 64 wires 20. The wire diameter of the wires 20 can be set depending on the size of the basket 30, the number of wires 20, the material, etc. The number of wires 20 in the basket 30 is preferably 16 to 32.

[0018] 1 and 2 , the connecting member 80 is disposed proximal to the basket 30. The connecting member 80 is a member that connects the basket 30 and the basket pusher 40. In other words, the basket 30 and the basket pusher 40 are directly or indirectly connected via the connecting member 80. Because the medical device 1 has the connecting member 80 proximal to the basket 30 and distal to the basket pusher 40, the basket 30 and the basket pusher 40 can be easily connected to each other.

[0019] 1 and 2 , the basket pusher 40 is disposed proximal to the connecting member 80. The basket pusher 40 is connected to the basket 30 via the connecting member 80, and can move the basket 30 in the longitudinal direction of the outer cylinder 10 to release the basket 30 from the outer cylinder 10 or store the basket 30 within the outer cylinder 10. Although not shown, the basket pusher 40 may be provided with a handle at the proximal end of the outer cylinder 10 for controlling its position in the longitudinal direction and rotation.

[0020] The material constituting the basket pusher 40 is preferably a metal, such as stainless steel, carbon steel, or a nickel-titanium alloy. Among these, the material constituting the basket pusher 40 is preferably stainless steel. Using stainless steel as the material constituting the basket pusher 40 can increase the rigidity of the basket pusher 40. As a result, the force applied to the basket pusher 40 can be efficiently transmitted to the basket 30, making it easier to move the basket 30 in the longitudinal direction.

[0021] As shown in FIGS. 1 and 2 , the connecting member 80 includes a distal member 81 and a proximal member 82, and the distal member 81 is rotatable relative to the proximal member 82. Because the distal member 81 of the connecting member 80 is rotatable relative to the proximal member 82, the connecting member 80 can be bent, allowing the basket 30 to be tilted relative to the basket pusher 40. Therefore, for example, when the basket 30 is placed inside the aneurysm after passing through the opening of the aneurysm, the connecting member 80 is bent by pushing the basket pusher 40, causing the distal end of the basket 30 to rotate toward the proximal side. As a result, the side surface of the basket 30 can be oriented toward the opening of the aneurysm. Because the gaps between the multiple wires 20 in the side surface of the basket 30 tend to be larger than those at the proximal and distal ends of the basket 30, it is easier to insert a long medical object, such as a coil, into the basket 30 through the gaps between the multiple wires 20.

[0022] Fig. 3 is a cross-sectional view parallel to the extension direction of the basket pusher 40 in a state in which the basket 30 is housed in the outer cylinder 10. In Fig. 3, the right side of the drawing is the proximal side, and the left side of the drawing is the distal side.

[0023] As shown in FIG. 3 , the medical device 1 includes an outer tube 10 having a distal end 10d and a proximal end 10p. The basket 30 is disposed within the inner cavity of the outer tube 10 and is preferably expandable upon exiting the outer tube 10. That is, the basket 30 is disposed within a lumen of the outer tube 10 and is preferably expandable upon release from the outer tube 10. When disposed within the inner cavity of the outer tube 10, the basket 30 contacts the inner wall of the outer tube 10 and is contracted and reduced in diameter upon receiving an external force from the outer tube 10. When released from the outer tube 10, the basket 30 is no longer subjected to that external force and, in the absence of any other external force, expands and is in an expanded state. Disposing the basket 30 within the inner cavity of the outer tube 10 facilitates transport of the basket 30 to a target site, facilitating procedures such as embolization using the medical device 1.

[0024] The outer cylinder 10 is a tubular member extending in the longitudinal direction and has at least one lumen extending in the longitudinal direction. The outer cylinder 10 may have multiple lumens, but preferably has one. By having only one lumen, the outer diameter of the outer cylinder 10 can be reduced. As a result, the minimal invasiveness of the medical device 1 can be improved.

[0025] The material constituting the outer tube 10 is preferably a resin or metal. Examples of resins constituting the outer tube 10 include polyamide-based resins, polyester-based resins, polyurethane-based resins, polyolefin-based resins, fluorine-based resins, vinyl chloride-based resins, silicone-based resins, and natural rubber. These may be used alone or in combination. Among these, the resin constituting the outer tube 10 is preferably at least one of polyamide-based resins, polyester-based resins, polyurethane-based resins, polyolefin-based resins, and fluorine-based resins. By using at least one of polyamide-based resins, polyester-based resins, polyurethane-based resins, polyolefin-based resins, and fluorine-based resins as the material constituting the outer tube 10, the surface slipperiness of the outer tube 10 can be improved, thereby improving insertion into a lumen such as a blood vessel. The resin tube that forms the outer tube 10 can be manufactured using conventional methods such as extrusion molding and injection molding.

[0026] Examples of metals that can be used to form the outer tube 10 include stainless steels such as SUS304 and SUS316, platinum, nickel, cobalt, chromium, titanium, tungsten, gold, Ni-Ti alloys, Co-Cr alloys, and combinations thereof. The metal tube that forms the outer tube 10 may be a tube made by spirally winding metal wire or a tube made by braiding metal wire. The outer tube 10 may also be a tube made by combining metal and resin. The outer tube 10 may be a resin tubular body with a reinforcing material such as a metal wire. When the outer tube 10 is a resin tubular member with a wire disposed therein, a Ni-Ti alloy wire is preferred due to its excellent shape memory and high elasticity. The wire may also be the above-mentioned metal or a fiber material such as polyarylate fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, PBO fiber, or carbon fiber. The fiber material may be monofilament or multifilament.

[0027] The outer cylinder 10 may be made of a single layer or multiple layers. Also, in the longitudinal direction, a portion of the outer cylinder 10 may be made of a single layer, and another portion may be made of multiple layers.

[0028] The outer surface of the sheath 10 is preferably coated with a hydrophilic resin. That is, the sheath 10 preferably has a hydrophilic resin layer on the outside of the sheath 10. Coating the outer surface of the sheath 10 with a hydrophilic resin increases the slipperiness of the sheath 10, thereby improving the insertability within a lumen in a living body.

[0029] Furthermore, the outer cylinder 10 preferably has an inner surface coated with a fluororesin. In other words, the outer cylinder 10 preferably has a fluororesin layer on the inside of the outer cylinder 10. By having a fluororesin layer on the inside of the outer cylinder 10, the slipperiness of the inner surface of the outer cylinder 10 is improved. Therefore, it becomes easier to move the basket 30 in the longitudinal direction in the inner cavity of the outer cylinder 10.

[0030] The cross-sectional shape of the outer shape of the outer cylinder 10 in a cross section perpendicular to the longitudinal axis direction may be circular, elliptical, polygonal, or a combination thereof. The cross-sectional shape of the inner cavity of the outer cylinder 10 in a cross section perpendicular to the longitudinal axis direction may also be circular, elliptical, polygonal, or a combination thereof.

[0031] The basket 30 is preferably slidable within a cylinder having an inner diameter of 0.021 inches (0.5334 mm) or less. When the outer cylinder 10 has one lumen, the inner diameter of the outer cylinder 10 is preferably 0.021 inches or less, and the basket 30 is disposed within the lumen of this outer cylinder 10. Furthermore, when the outer cylinder 10 has multiple lumens, the inner diameter of the lumen in which the basket 30 is disposed is preferably 0.021 inches or less. By allowing the basket 30 to slide within a cylinder having an inner diameter of 0.021 inches or less, the outer diameter of the outer cylinder 10 can be reduced, resulting in a medical device 1 that is easy to insert and minimally invasive.

[0032] It is preferable that the connecting member 80 is separable, allowing the basket 30 to be detached from the basket pusher 40. In other words, it is preferable that the basket 30 can be detached from the basket pusher 40 by separating the connecting member 80. Because the connecting member 80 is separable, the basket 30 can be detached from the basket pusher 40 by separating the connecting member 80 after transporting the basket 30 to the target site, making it easier to place the basket 30 at the target site.

[0033] The connection member 80 can be separated by various methods such as a mechanical separation mechanism, melting, thermal, electrical, or chemical separation.

[0034] As shown in FIG. 2 , it is preferable that one of the distal side member 81 and the proximal side member 82 has a spherical portion 83, and the other of the distal side member 81 and the proximal side member 82 has a covering portion 84 that covers the spherical portion 83. That is, the connecting member 80 has a spherical portion 83 and a covering portion 84, and when the distal side member 81 has the spherical portion 83, it is preferable that the proximal side member 82 has the covering portion 84, and when the distal side member 81 has the covering portion 84, it is preferable that the proximal side member 82 has the spherical portion 83. When one of the distal side member 81 and the proximal side member 82 has the spherical portion 83 and the other of the distal side member 81 and the proximal side member 82 has the covering portion 84, the covering portion 84 slides over the spherical portion 83, thereby bending the connecting member 80. This allows the connecting member 80 to bend smoothly, and also makes it easier to control the degree of bending of the connecting member 80.

[0035] 2 , when the connecting member 80 has a spherical portion 83 and a covering portion 84, it is preferable that the proximal member 82 has an inner cavity extending in the longitudinal axis direction and further has an elongated member 86 inserted into this inner cavity, and that the distal end of this elongated member 86 contacts the spherical portion 83 or the covering portion 84. Specifically, when the proximal member 82 has the covering portion 84 and the distal member 81 has the spherical portion 83, it is preferable that the distal end of the elongated member 86 contacts the spherical portion 83, and when the proximal member 82 has the spherical portion 83 and the distal member 81 has the covering portion 84, it is preferable that the distal end of the elongated member 86 contacts the covering portion 84. Since the connecting member 80 has a spherical portion 83 and a covering portion 84, and the medical device 1 has an elongated member 86, when the distal end of the elongated member 86 comes into contact with the spherical portion 83 or the covering portion 84, either the spherical portion 83 or the covering portion 84 is pushed out from the other, and the connection between the spherical portion 83 and the covering portion 84 can be easily released.

[0036] Figure 4 is an enlarged view of a portion of a medical device 1 according to another embodiment of the present invention, where a connecting member 80 is located. Note that in Figure 4, the right side of the figure is the proximal side, and the left side of the figure is the distal side. Also, in Figure 4, to make it easier to understand the positional relationship between each member and part, only some of the multiple wires 20 of the basket 30 are shown, and the other wires are not shown.

[0037] 4 , it is also preferable that the connecting member 80 has a shaft member 85 proximal to the distal member 81 and distal to the proximal member 82, and that the shaft member 85 is inserted through the distal member 81 and the proximal member 82. That is, it is also preferable that the connecting member 80 has the distal member 81, the proximal member 82, and the shaft member 85, and that the distal member 81 and the proximal member 82 are connected by inserting the shaft member 85 through the distal member 81 and the proximal member 82. It is also preferable that the connecting member 80 has the shaft member 85 proximal to the distal member 81 and distal to the proximal member 82, and that the shaft member 85 is inserted through the distal member 81 and the proximal member 82, so that the distal member 81 can rotate relative to the proximal member 82 around the shaft member 85 as an axis of rotation. Therefore, the bending of the connection member 80 tends to be smooth, and the bending of the connection member 80 tends to be easily controlled.

[0038] As shown in FIG. 4 , it is preferable that the basket pusher 40 has an inner cavity extending in the longitudinal axis direction, and that an elongated member 86 that contacts the connecting member 80 is disposed in this inner cavity. Specifically, it is preferable that the medical device 1 has the elongated member 86, that the elongated member 86 is disposed in the inner cavity of the basket pusher 40, and that the distal end of the elongated member 86 contacts the proximal end of the connecting member 80. Because the medical device 1 has the elongated member 86, the elongated member 86 comes into contact with the connecting member 80, and the connecting member 80 is pushed out of the basket pusher 40. As a result, the connecting member 80 is separated from the basket pusher 40, and the basket 30 can be detached from the basket pusher 40.

[0039] Although not shown, the connecting member 80 may further include another member proximal to the proximal member 82, and this member may be connected to the proximal member 82. The connecting member 80 may further include another member distal to the distal member 81, and this member may be connected to the distal member 81. Furthermore, the connecting member 80 may be configured to include a spherical portion 83, a covering portion 84, and an axial member 85. The connecting member 80 having the spherical portion 83, the covering portion 84, and the axial member 85 allows the connecting member 80 to be bent in various directions.

[0040] Examples of materials that constitute the connection member 80 include metals, resins, and combinations thereof. Examples of metals that constitute the connection member 80 include stainless steel, carbon steel, and nickel-titanium alloys. Examples of resins that constitute the connection member 80 include polyamide resins, polyolefin resins, fluorine-based resins, polycarbonate resins, and PVA (polyvinyl alcohol).

[0041] In the connecting member 80, the distal side member 81 and the proximal side member 82 may be made of metal, or the distal side member 81 and the proximal side member 82 may be made of resin. Also, the distal side member 81 may be made of metal and the proximal side member 82 may be made of resin, or the distal side member 81 may be made of resin and the proximal side member 82 may be made of metal.

[0042] At least one of the material constituting the distal side member 81 and the material constituting the proximal side member 82 is preferably metal. By using a metal for at least one of the material constituting the distal side member 81 and the material constituting the proximal side member 82, the strength of the connecting member 80 is increased, and the connecting member 80 is less likely to break even when repeatedly bent.

[0043] A portion of the connecting member 80 may include a heat-melting member that melts when heated, and the medical device 1 may include a heating mechanism 90 that heats the heat-melting member. Because the connecting member 80 includes a heat-melting member that melts when heated, the connecting member 80 melts and breaks when the heat-melting member is heated by the heating mechanism 90. This makes it easy to separate the connecting member 80 and detach the basket 30 from the basket pusher 40.

[0044] The material that melts when heated and that constitutes the heat-melting member contained in the connecting member 80 is preferably a thermoplastic resin, and more preferably PVA (polyvinyl alcohol). By using PVA as the material that constitutes the heat-melting member contained in the connecting member 80, the connecting member 80 can be more easily separated, making it possible to provide a medical device 1 that is easy to handle.

[0045] The heating mechanism 90 is preferably connected to the basket pusher 40. By connecting the heating mechanism 90 to the basket pusher 40, the heat-melting member included in the connecting member 80 can be heated via the basket pusher 40, eliminating the need to provide a separate member for transferring heat from the heating mechanism 90 to the heat-melting member, and allowing the medical device 1 to be made smaller.

[0046] 3 , the length of the connecting member 80 in the extension direction of the basket pusher 40 is preferably shorter than the length of the basket pusher 40 and the length of the basket 30. By making the length of the connecting member 80 in the extension direction of the basket pusher 40 shorter than the length of the basket pusher 40 and the length of the basket 30, the force applied to the basket pusher 40 from the proximal side toward the distal side in order to transport the basket 30 to the target site is more easily transmitted to the basket 30, making it easier to transport the basket 30 smoothly.

[0047] The length of the connecting member 80 in the extension direction of the basket pusher 40 is preferably 70% or less of the length of the basket 30, more preferably 60% or less, and even more preferably 50% or less. By setting the upper limit of the ratio of the length of the connecting member 80 to the length of the basket 30 within the above range, the strength of the connecting member 80 is increased, and the force that pushes the basket pusher 40 and moves it distally is more easily transmitted to the basket 30. Furthermore, the length of the connecting member 80 in the extension direction of the basket pusher 40 is preferably 5% or more of the length of the basket 30, more preferably 7% or more, and even more preferably 10% or more. By setting the lower limit of the ratio of the length of the connecting member 80 to the length of the basket 30 within the above range, the connecting member 80 becomes more easily bent, making it easier to rotate the basket 30 relative to the basket pusher 40.

[0048] 1 , when the distal side member 81 is rotated relative to the proximal side member 82, the angle θ1 formed proximally between the extension direction L1 of the basket pusher 40 and a line L2 passing through the distal end 30d of the basket 30 and the proximal end 30p of the basket 30 is preferably 45 degrees or more and 150 degrees or less. When the angle θ1 formed proximally between the extension direction L1 of the basket pusher 40 and the line L2 passing through the distal end 30d of the basket 30 and the proximal end 30p of the basket 30 is 45 degrees or more and 150 degrees or less, the connecting member 80 is likely to be bent, and the basket 30 is likely to be sufficiently inclined relative to the basket pusher 40. As a result, for example, when the basket 30 is placed inside the aneurysm after passing through the opening of the aneurysm, the basket 30 is rotated by pushing the basket pusher 40, and the side surface of the basket 30 can be oriented toward the opening of the aneurysm. Since the gaps between the multiple wires 20 of the basket 30 tend to be larger at the side portions of the basket 30 than at the proximal and distal ends of the basket 30, it is easier to insert long medical objects such as coils into the basket 30 through the gaps between the multiple wires 20.

[0049] As shown in Figure 1, when the distal end of the basket 30 is concave, the midpoint of an imaginary line (shown by a dashed line in Figure 1) connecting the most distal portions of at least two wires 20 that the basket 30 has is defined as the distal end 30d of the basket 30.

[0050] The angle θ1 formed on the proximal side between the extension direction L1 of the basket pusher 40 and a straight line L2 passing through the distal end 30d of the basket 30 and the proximal end 30p of the basket 30 is preferably equal to or greater than 45 degrees, more preferably equal to or greater than 50 degrees, even more preferably equal to or greater than 55 degrees, even more preferably equal to or greater than 60 degrees, and particularly preferably equal to or greater than 65 degrees. By setting the lower limit of the angle θ1 within the above range, the basket 30 can be more easily rotated toward the lateral side than the distal end 30d of the basket 30, making it easier to insert a long medical object such as a coil through gaps between the multiple wires 20 of the basket 30. Furthermore, the angle θ1 formed on the proximal side between the extension direction L1 of the basket pusher 40 and a straight line L2 passing through the distal end 30d of the basket 30 and the proximal end 30p of the basket 30 is preferably 150 degrees or less, more preferably 145 degrees or less, even more preferably 140 degrees or less, still more preferably 135 degrees or less, particularly preferably 130 degrees or less, more particularly preferably 125 degrees or less, and most preferably 120 degrees or less. By setting the upper limit of the angle θ1 within the above range, the basket 30 can be more easily rotated toward the lateral side of the proximal end 30p of the basket 30, making it easier to insert an elongated medical object between the multiple wires 20 that the basket 30 has.

[0051] 1 and 3 , the basket 30 includes a first bundling portion 51 that bundles and secures the plurality of wires 20 at its distal portion, and a second bundling portion 52 that bundles and secures the plurality of wires 20 at its proximal portion, and the first bundling portion 51 and the second bundling portion 52 preferably contain a radiopaque material. Because the first bundling portion 51 and the second bundling portion 52 contain a radiopaque material, the positions of the first bundling portion 51 at the distal portion of the basket 30 and the second bundling portion 52 at the proximal portion of the basket 30 can be confirmed under X-ray fluoroscopy. As a result, the position of the basket 30 within the body can be determined.

[0052] Examples of radiopaque materials include platinum, gold, tungsten, iridium, tantalum, and alloys of at least one of these.

[0053] The basket 30 is preferably configured in a cage shape by braiding a plurality of bent wires 20 or right-handed and left-handed spiral wires 20 between the first bundling part 51 and the second bundling part 52. In particular, the basket 30 is preferably configured by braiding right-handed spiral wires 20 and left-handed spiral wires 20. By configuring the basket 30 by braiding right-handed spiral wires 20 and left-handed spiral wires 20, the basket 30 has a cage-like shape with mesh-like walls. As a result, objects contained inside the basket 30 are less likely to escape to the outside of the basket 30, making it easier to efficiently promote thrombosis.

[0054] Methods for bundling and securing the plurality of wires 20 in the first bundling section 51 and the second bundling section 52 include, for example, welding the plurality of wires 20, crimping the plurality of wires 20 together with a separate member, bonding with an adhesive, securing with a brazing material, and combinations thereof. Among these, it is preferable to secure the plurality of wires 20 by crimping them with a separate member in the first bundling section 51 and the second bundling section 52. By crimping and securing the plurality of wires 20 with a separate member in the first bundling section 51 and the second bundling section 52, the plurality of wires 20 can be more firmly secured in the first bundling section 51 and the second bundling section 52, making the basket 30 less susceptible to damage.

[0055] In the first bundling section 51 and the second bundling section 52, examples of the separate member that bundles and secures the multiple wires 20 include a ring-shaped member, a member with a C-shaped cross section with a notch in the ring, a coil-shaped member with a wound wire, and a member that ties and secures the multiple wires 20 with a string-like material. Among these, the separate member that bundles and secures the multiple wires 20 is preferably a ring-shaped member, and more preferably, the ring-shaped member is held or secured by swaging. By using a ring-shaped member that bundles and secures the multiple wires 20 and is held or secured by swaging, the multiple wires 20 can be firmly secured and the multiple wires 20 can be made difficult to unbind.

[0056] The separate member that ties together and secures the wires 20 can be made of a material similar to that of the wires 20 of the basket 30 or the basket pusher 40. Among these, the separate member that ties together and secures the wires 20 is preferably made of stainless steel. Using stainless steel as the material for the separate member that ties together and secures the wires 20 can increase the strength of the wires 20 and improve the durability of the separate member that ties together and secures the wires 20. Furthermore, the separate member that ties together and secures the wires 20 is preferably made of a radiopaque material. Examples of radiopaque materials include platinum, gold, tungsten, iridium, tantalum, and alloys of at least one of these metals. By using a radiopaque material for the separate member that ties together and secures the wires 20, the positions of the first bundling portion 51 and the second bundling portion 52 can be confirmed under X-ray fluoroscopy, making it possible to determine the position of the basket 30 within the body.

[0057] As shown in Fig. 3, when the basket 30 is housed in the outer tube 10, the first bundling portion 51 is preferably located distal to the distal ends 20d of the wires 20. The first bundling portion 51 is a portion that bundles and secures the plurality of wires 20 of the basket 30. When the basket 30 is housed in the outer tube 10, the first bundling portion 51 is located distal to the distal ends 20d of the wires 20, which makes it difficult for the plurality of wires 20 bundled by the first bundling portion 51 to come apart. This makes it easier to release the basket 30 from the outer tube 10 while the plurality of wires 20 maintain their respective phases.

[0058] As shown in Figure 3, the second bundling part 52 is preferably located more proximal than the proximal end 20p of the wire 20. Like the first bundling part 51, the second bundling part 52 is a part that bundles and secures the multiple wires 20 of the basket 30, and therefore tends to be more rigid than other parts of the basket 30. By locating the second bundling part 52 more proximal than the proximal end 20p of the wire 20, the rigidity of the proximal end of the basket 30 can be increased, and a force applied from the proximal side to push the basket 30 distally can be efficiently transmitted to the basket 30. As a result, the medical device 1 can be configured to easily release the basket 30 from the outer tube 10.

[0059] The wire 20 of the basket 30 preferably contains a superelastic alloy. When the wire 20 contains a superelastic alloy, the basket 30 has excellent elasticity. The excellent elasticity of the basket 30 allows the basket 30 to have a large deformation amount. Therefore, the basket 30 can be housed in an outer tube 10 with a small outer diameter, and when the basket 30 is outside the outer tube 10, the basket 30 can be greatly expanded.

[0060] The wire 20 of the basket 30 preferably contains a radiopaque material. By including the radiopaque material in the wire 20, it becomes possible to check the expanded state and position of the basket 30 under X-ray fluoroscopy, which makes it easier to perform the procedure smoothly.

[0061] As described above, the medical device of the present invention includes a basket having multiple wires, a connecting member disposed proximal to the basket, and a basket pusher disposed proximal to the connecting member. The connecting member includes a distal member and a proximal member, and the distal member is rotatable relative to the proximal member. With this configuration of the medical device of the present invention, the distal member and the proximal member can be rotated to bend the connecting member, thereby tilting the basket connected to the basket pusher via the connecting member relative to the basket pusher. Therefore, for example, when the basket is placed inside the aneurysm after passing through the opening of the aneurysm, the side surface of the basket can be oriented toward the opening of the aneurysm. Because the gaps between the multiple wires of the basket tend to be larger at the side surface of the basket than at the proximal and distal ends of the basket, it is easier to insert a long medical object, such as a coil, into the basket through the gaps between the multiple wires.

[0062] This application claims the benefit of priority based on Japanese Patent Application No. 2022-053545, filed on March 29, 2022. The entire contents of the specification of Japanese Patent Application No. 2022-053545, filed on March 29, 2022, are incorporated herein by reference.

[0063] 1: Medical device 10: Sheath 10d: Distal end of sheath 10p: Proximal end of sheath 20: Wire 20d: Distal end of wire 20p: Proximal end of wire 30: Basket 30d: Distal end of basket 30p: Proximal end of basket 40: Basket pusher 51: First binding part 52: Second binding part 80: Connecting member 81: Distal side member 82: Proximal side member 83: Spherical part 84: Covering part 85: Shaft member 86: Elongated member 90: Heating mechanism L1: Extension direction of basket pusher L2: Straight line passing through the distal end and proximal end of the basket θ1: Angle formed proximally between the extension direction of the basket pusher and the straight line passing through the distal end and proximal end of the basket

Claims

1. a basket having a plurality of wires; a connecting member disposed proximally of the basket; a basket pusher disposed proximally of the connecting member and having an internal cavity; an elongate member disposed in the lumen, The connecting member includes a distal member and a proximal member, the distal member is formed to be rotatable relative to the proximal member, A medical device in which the distal end of the elongate member is contactable with the proximal end of the connecting member.

2. a barrel having a distal end and a proximal end; The medical device of claim 1 , wherein the basket is disposed within the inner lumen of the sheath and is expandable once outside the sheath.

3. The connecting member is separable; The medical device according to claim 1 or 2, wherein the basket is detachable from the basket pusher.

4. one of the distal member and the proximal member has a spherical portion; The medical device according to claim 1 or 2, wherein the other of the distal member and the proximal member has a covering portion that covers the spherical portion.

5. the connecting member has a shaft member proximal to the distal member and distal to the proximal member, The medical device according to claim 1 or 2, wherein the shaft member is inserted through the distal member and the proximal member.

6. The medical device according to claim 1 or 2, wherein at least one of the material constituting the distal member and the material constituting the proximal member is a metal.

7. 3. The medical device of claim 1, wherein when the distal member is rotated relative to the proximal member, the angle formed by the extension direction of the basket pusher and a line passing through the distal end of the basket and the proximal end of the basket on the proximal side is greater than or equal to 45 degrees and less than or equal to 150 degrees.

8. The basket includes a first bundling portion at a distal portion thereof that bundles and fixes the plurality of wires, and a second bundling portion at a proximal portion thereof that bundles and fixes the plurality of wires, The medical device according to claim 1 or 2, wherein the first binding portion and the second binding portion contain a radiopaque material.