Medical device

Abstract

The medical device includes a tube and a probe. The tube has a lumen for inserting a guide component. The probe protrudes forward from the front end of the tube, and the maximum value of its width in a first direction orthogonal to the central axis of the tube is greater than the maximum value of its width in a second direction orthogonal to both the central axis and the first direction. The front end of the probe is configured to be located on the side of the second direction relative to the tube.

Description

Technical Field

[0001] The technology disclosed in this specification relates to a medical device. Background Technology

[0002] Atherosclerosis resection device is known as a medical device used in the treatment of narrowed or blocked sections (hereinafter referred to as "lesions") in blood vessels, etc. The atherosclerosis resection device removes thrombi, plaques, etc., that form the lesion by excising the lesion.

[0003] Conventionally, an atherosclerosis resection assembly (medical device) has been disclosed, comprising a front-end cutter (excavation section) and a guidewire orifice for inserting a guidewire (guiding component) (see, for example, Patent Document 1). In this atherosclerosis resection assembly, firstly, a guidewire is inserted through the guidewire orifice and pre-guided to a location such as a thrombus within the blood vessel. Next, the front-end cutter is advanced to the location of the thrombus within the blood vessel, and the front-end cutter is rotated, thereby removing the thrombus from the vessel wall. In this atherosclerosis resection assembly, when the guidewire is inserted through the guidewire orifice, the front end of the front-end cutter covers the entire circumference of the guidewire.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2017-12909 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] When the excavating part is rotated to excavate the lesion, in a structure where the front end of the excavating part covers the entire circumference of the outer edge of the guide member, as in the prior art described above, the front end face of the excavating part continuously contacts the lesion present around the outer surface of the guide member. Therefore, the following problem arises: the edge of the excavating part, formed at a predetermined angle to be excavated, is difficult to contact the lesion present around the outer surface of the guide member, and the lesion present around the outer surface of the guide member remains un-ground away.

[0009] This specification discloses a technique that can solve the above-mentioned problems.

[0010] Solution for solving the problem

[0011] The techniques disclosed in this specification can be implemented, for example, in the following ways.

[0012] The medical device disclosed in this specification includes a tube and a probe. The tube has a lumen for inserting a guide member. The probe protrudes further forward than the front end of the tube, and the maximum value of its width in a first direction orthogonal to the central axis of the tube is greater than the maximum value of its width in a second direction orthogonal to both the central axis and the first direction. The front end of the probe is configured to be located on one side of the second direction relative to the tube. Attached Figure Description

[0013] Figure 1 This is an explanatory diagram that roughly shows the structure of the side of the medical device 10.

[0014] Figure 2 This is an explanatory diagram that roughly shows the longitudinal section of the medical device 10.

[0015] Figure 3 It is a general representation Figure 2 An explanatory diagram of the cross-sectional structure of the medical device 10 at position III-III.

[0016] Figure 4 It is a general representation Figure 2 An explanatory diagram of the cross-sectional structure of the medical device 10 at the IV-IV position.

[0017] Figure 5 This is an explanatory diagram showing the detailed structure of the excavation unit 200 in the embodiment.

[0018] Figure 6 This is an explanatory diagram showing the detailed structure of the excavation unit 200 in the embodiment.

[0019] Figure 7 This is an explanatory diagram that roughly shows the structure of the front end of the medical device 10.

[0020] Figure 8 This is an explanatory diagram that roughly shows the structure of the front end of the medical device 10.

[0021] Figure 9 This is an explanatory diagram illustrating an example of how to use the medical device 10.

[0022] Figure 10 This is an explanatory diagram showing the detailed structure of the excavation section 200a in the modified example. Detailed Implementation

[0023] A. Implementation method:

[0024] A-1. Structure of Medical Device 10:

[0025] Figure 1 This is an explanatory diagram that roughly shows the structure of the side of the medical device 10. Figure 1This shows the structure of the side of the medical device 10, and also the structure of the side of the guidewire 20 used in the treatment with the medical device 10. Figure 1 In the figures shown thereafter, the mutually orthogonal XYZ axes are represented to determine the direction. Figure 1 In this procedure, the positive Z-axis side is the distal end (distal side) of the insertion site, while the negative Z-axis side is the proximal end (proximal side) operated on by the surgeon. Figure 1 The illustration of a portion of medical device 10 is omitted. Figure 1 In this context, it indicates that the central axis AX1 of the medical device 10 is in a straight line parallel to the Z-axis direction, but the medical device 10 has a degree of flexibility that allows it to bend.

[0026] In this specification, regarding the medical device 10 and its constituent parts, the end on the front end side is referred to as the "front end," the front end and its vicinity as the "front end portion," the end on the base end side is referred to as the "base end," and the base end and its vicinity as the "base end portion." Furthermore, the longitudinal section of the medical device 10 and its constituent parts refers to the section including the central axis AX1 (e.g., the YZ section), and the cross section of the medical device 10 and its constituent parts refers to the section orthogonal to the central axis AX1 (the XY section). These points are also consistent in the following figures.

[0027] Medical device 10 is a long, thin device inserted into a blood vessel to treat lesions (stenosis, occlusion) within the vessel. Medical device 10 removes thrombi, plaques, etc., that have formed the lesion by excavating the lesion. The total length of medical device 10 is, for example, between 1500 mm and 2000 mm.

[0028] Guidewire 20 is used by medical device 10 to treat lesions within blood vessels. Guidewire 20 is a long, strip-shaped component extending along the central axis AX1 of medical device 10, and is made of, for example, metal wire. The cross-sectional shape of guidewire 20 at various locations can be any shape, such as circular. The outer diameter of guidewire 20 is, for example, about 0.2 mm or more and about 0.8 mm less. The total length of guidewire 20 is, for example, about 2000 mm or more and about 3000 mm less. Guidewire 20 is an example of a guiding component.

[0029] Materials used to form the guidewire 20 include, for example, stainless steel (SUS302, SUS304, SUS316, etc.), Ni-Ti alloy, piano wire, etc. The guidewire 20 can be made entirely of the same material, or each part can be made of different materials.

[0030] Figure 2 This is an explanatory diagram that roughly shows the longitudinal section of the medical device 10. Figure 3 It is a general representation Figure 2An explanatory diagram of the cross-sectional structure of the medical device 10 at position III-III. Figure 4 It is a general representation Figure 2 An explanatory diagram of the cross-sectional structure of the medical device 10 at the IV-IV position.

[0031] The medical device 10 includes a tube 100, a digging part 200, a fixing part 300, an inner coil body 400, an outer coil body 500, an inner catheter 600, an outer catheter 700, a connector 800, and a motor driver 900.

[0032] Tube 100 is a hollow tubular component extending parallel to the central axis AX1 of the medical device 10. For example... Figure 4 As shown, tube 100 has a lumen 102 for inserting guide wire 20.

[0033] The excavation section 200 is a component that protrudes further towards the front end than the front end of the pipe 100. For example... Figure 4 As shown, the base of the excavating section 200 is connected to the tube 100. The excavating section 200 and the tube 100 are joined, for example, by brazing filler metal (aluminum alloy brazing filler metal, silver brazing filler metal, gold brazing filler metal, etc.). The detailed structure of the excavating section 200 will be described later.

[0034] The fixing part 300 is a hollow tubular component extending parallel to the central axis AX1 of the medical device 10. For example... Figure 2 as well as Figure 4 As shown, the inner surface of the fixing part 300 is connected to the base end of the digging part 200 and the tube 100 respectively, and the base end of the digging part 200 and the tube 100 are fixed by binding. The fixing part 300 is joined to the tube 100 and the digging part 200 respectively by brazing filler metal (aluminum alloy brazing filler metal, silver brazing filler metal, gold brazing filler metal, etc.).

[0035] The inner coil body 400 is a hollow tubular component extending parallel to the central axis AX1 of the medical device 10. The inner coil body 400 is constructed by winding one or more wires. In this embodiment, the inner coil body 400 is composed of multiple coils with multiple wires wound around them, and each wire constituting the inner coil body 400 is a single wire. Furthermore, the inner coil body 400 of this embodiment is a single-layer coil composed of one layer. Figure 3 As shown, a cavity 402 for inserting the guide wire 20 is formed inside the inner coil body 400. Additionally, as... Figure 2 As shown, the outer surface of the front end of the inner coil body 400 is connected to the inner surface of the fixing part 300. The inner coil body 400 and the fixing part 300 are joined, for example, by a solder (aluminum alloy solder, silver solder, gold solder, etc.). The outer diameter of the inner coil body 400 is, for example, about 0.3 mm or more and about 1.0 mm or less.

[0036] The outer coil body 500 is, for example, a coil-shaped component constructed by winding a wire. Figure 2 and Figure 3 As shown, the outer coil body 500 is configured to run along the outer surface of the inner coil body 400, and the inner surface of the outer coil body 500 is connected to the outer surface of the inner coil body 400. The outer coil body 500 and the inner coil body 400 are joined, for example, by a solder (aluminum alloy solder, silver solder, gold solder, etc.).

[0037] The inner catheter 600 is a hollow tubular component extending parallel to the central axis AX1 of the medical device 10. A lumen is formed inside the inner catheter 600, extending from its tip to its base. For example... Figure 1 as well as Figure 2 As shown, the lumen formed in the inner conduit 600 is wider than the fixing part 300 and the outer coil body 500 in a direction orthogonal to the central axis AX1, and can accommodate the fixing part 300 and the outer coil body 500. The inner diameter of the inner conduit 600 is, for example, about 1.8 mm.

[0038] The lateral catheter 700 is a hollow tubular component extending parallel to the central axis AX1 of the medical device 10. A lumen is formed inside the lateral catheter 700, extending from its tip to its base. For example... Figure 1 As shown, the lumen formed in the outer conduit 700 is wider than the inner conduit 600 in a direction orthogonal to the central axis AX1, and is capable of accommodating the inner conduit 600. The inner diameter of the outer conduit 700 is, for example, about 2.2 mm.

[0039] The connector 800 is a hollow tubular component extending parallel to the central axis AX1 of the medical device 10. The connector 800 has three openings. Two of the three openings facing the Z-axis are for connecting the inner coil body 400, located at the front end of the connector 800, to the motor driver 900 located at the base end of the connector 800. The other opening, facing a direction intersecting the Z-axis, is connected, for example, to a suction machine, functioning as a suction port for removing chips excavated by the excavating unit 200.

[0040] The motor driver 900 is a device for controlling the rotation of the inner coil body 400. The motor driver 900 has a motor inside, and the rotation of the motor is transmitted to the inner coil body 400.

[0041] A-2. Detailed structure of excavator 200:

[0042] Figure 5 as well as Figure 6 This is an explanatory diagram showing the detailed structure of the excavation unit 200 in the embodiment. Figure 5 The image shows a magnified view of the structure of the front end of the medical device 10 when viewed along the X-axis. Figure 6 The image shows a magnified view of the structure of the front end of the medical device 10 when viewed along the Y-axis.

[0043] The maximum width of the excavation section 200 in the Y-axis direction is greater than the maximum width in the X-axis direction. In other words, the excavation section 200 has a flat shape. Additionally, the excavation section 200 has a ring shape. Specifically, the excavation section 200 is, for example, made of metal wire. One end and the other end of the metal wire constituting the excavation section 200 are both disposed on the base end side of the excavation section 200 and are fixed to the fixing part 300 by bundling together with the tube 100. The portion between one end and the other end of the metal wire constituting the excavation section 200 forms a ring when viewed in the X-axis direction. A through hole 210 extending in the X-axis direction is formed inside the ring shape of the excavation section 200. The excavation section 200 extends in the Z-axis direction near the outer periphery of the tube 100, and the front end of the excavation section 200 is positioned closer to the front end side than the front end of the tube 100. The Y-axis direction is an example of a first direction, and the X-axis direction is an example of a second direction.

[0044] The shape of the cross-section of the metal wire constituting the excavation section 200 varies depending on its location. Specifically, the location of the maximum width in the Y-axis direction constituting the excavation section 200 ( Figure 5 The cross-section of the metal wire at the position of A1-A1 in the diagram and at the position near the base end, which is closer to the position of the maximum width in the Y-axis direction constituting the excavation section 200, is circular. Additionally, the cross-section of the metal wire at the position near the front end, which is closer to the position of the maximum width in the Y-axis direction constituting the excavation section 200 (for example, ... Figure 5 The cross-section of the metal wire at position A2-A2 (in the diagram) is straight on the outer side of the ring shape and arc-shaped on the inner side. That is, the cross-section of the metal wire at the front end, closer to the position where the width of the excavation section 200 is greater than its maximum width along the Y-axis, is semi-circular. The excavation section 200 is made of a hyperelastic material, such as a Ni-Ti alloy.

[0045] like Figure 6As shown, the front end of the excavation section 200 is configured to be located on one side (positive X-axis side) relative to the tube 100 in the X-axis direction. Furthermore, when the guidewire 20 is inserted, the front end of the excavation section 200 is also configured to be located on one side (positive X-axis side) relative to the guidewire 20 in the X-axis direction. In other words, when the guidewire 20 is inserted, the front end of the excavation section 200 does not cover the entire circumference of the outer edge of the guidewire 20. Moreover, the centerline CL of the excavation section 200 in the X-axis direction is located on one side (positive X-axis side) relative to the central axis AX1 of the medical device 10, while the central axis AX2 of the tube 100 is located on the other side (negative X-axis side) relative to the central axis AX1 of the medical device 10. That is, in the X-axis direction, the centerline CL of the excavation section 200 and the central axis AX2 of the tube 100 are offset relative to the central axis AX1 of the medical device 10.

[0046] Figure 7 and Figure 8 This is an explanatory diagram that roughly shows the structure of the front end of the medical device 10. (For example...) Figure 7 As shown, when the excavation portion 200 is not covered by the inner catheter 600, the width of the excavation portion 200 in the Y-axis direction is larger than the width of the inner catheter 600 and the outer catheter 700 in the Y-axis direction. Therefore, it is possible to form a hole in the lesion with a diameter larger than the outer diameter of the inner catheter 600 and the outer catheter 700. On the other hand, as... Figure 8 As shown, when the excavating section 200 is covered by the inner guide tube 600, the width of the excavating section 200 in the Y-axis direction is smaller than the width of the inner guide tube 600 in the Y-axis direction. Thus, the excavating section 200 is configured to be in a retractable state (e.g., Figure 8 The state of contraction and the state of expansion that expands in the Y-axis direction (e.g.) Figure 7 (State). As described above, the digging section 200 is made of a superelastic material, so even if the shape of the digging section 200 is deformed in the contracted state, it can easily return to its original shape when moved to the outside of the inner guide tube 600. In the expanded state, the width of the digging section 200 in the Y-axis direction is about 2 mm to 6 mm.

[0047] A-3. Instructions for using medical device 10:

[0048] The following is a detailed description of an example of how to use the medical device 10. Figure 9This is an explanatory diagram illustrating an example of how medical device 10 is used. First, the surgeon or other operator inserts guidewire 20 through lumen 402 and lumen 102. Next, the operator inserts guidewire 20 into blood vessel 30 and advances it until it passes through lesion 32 (e.g., chronic total occlusion). Then, the operator inserts medical device 10 into blood vessel 30 and advances it until its tip reaches lesion 32. At this point, before the tip of medical device 10 reaches lesion 32, the digging section 200 is advanced in a contracted state; when the tip of medical device 10 reaches lesion 32, the digging section 200 is dilated.

[0049] Next, the surgeon rotates the inner coil body 400 using the motor driver 900 while simultaneously bringing the excavation part 200 into contact with the lesion 32, thereby advancing the medical device 10 toward the distal side. At this time, the inner coil body 400 is connected to the excavation part 200 via the fixing part 300; therefore, by rotating the inner coil body 400, as... Figure 9 As shown, the rotation of the inner coil body 400 is transmitted to the excavation section 200. Thus, the excavation section 200 penetrates into the lesion section 32 and rotates within it, thereby excavating the lesion section 32. Simultaneously, the guidewire 20 passes through the lesion section 32, and its radial position is temporarily fixed by the lesion section 32, causing the excavation section 200 to rotate around the guidewire 20. At the same time, the surgeon uses a suction device to aspirate the debris generated during the excavation of the lesion section 32 through the opening of the connector 800. The debris is then recovered from the opening of the connector 800 through the space between the inner coil body 400 and the inner catheter 600. The surgeon then continues the excavation of the lesion section 32 by the medical device 10, thereby ultimately allowing the medical device 10 to pass through the lesion section 32.

[0050] A-4. Effects of this implementation method:

[0051] As described above, the medical device 10 has a tube 100 and a probe 200. The tube 100 has a lumen 102 for insertion of the guidewire 20. The probe 200 protrudes forward from the front end of the tube 100, and the maximum value of the width of the tube 100 in the Y-axis direction orthogonal to the central axis AX2 is greater than the maximum value of its width in the X-axis direction orthogonal to both the central axis AX2 and the Y-axis direction. The front end of the probe 200 is configured to be located on one side of the tube 100 in the X-axis direction.

[0052] According to the medical device 10 of this embodiment, the front end of the digging section 200 is configured such that it is located on one side of the tube 100 in the X-axis direction orthogonal to the central axis AX2 of the tube 100. That is, it is configured such that when the guidewire 20 is inserted, the front end of the digging section 200 is located on one side of the guidewire 20 in the X-axis direction. As a result, when the digging section 200 is rotated to dig out the lesion 32, the edge of the digging section 200 can easily come into contact with the lesion 32, preventing the lesion 32 present around the outer surface of the guidewire 20 from remaining uncut, thereby improving the digging performance of the medical device 10 on the lesion 32.

[0053] Furthermore, in the medical device 10 of this embodiment, the digging section 200 is configured to be in a contracted state and an expanded state that expands in the Y-axis direction compared to the contracted state. According to the medical device 10 of this embodiment, the digging section 200 can be in both a contracted and expanded state, thus enabling it to travel within the blood vessel 30 in a contracted state and to dig into the lesion 32 in an expanded state. Therefore, compared to a structure where the digging section 200 cannot be in either a contracted or expanded state, the digging diameter of the medical device 10 can be increased while ensuring ease of movement within the blood vessel 30, thereby more effectively improving the digging performance of the medical device 10 in excavating the lesion 32.

[0054] Furthermore, in the medical device 10 of this embodiment, the excavation section 200 is made of a hyperelastic material and has a ring shape. According to the medical device 10 of this embodiment, the excavation section 200 is made of a hyperelastic material, thus improving durability against shape changes. Furthermore, the ring shape of the excavation section 200 improves the safety of surgeries performed using the medical device 10.

[0055] Furthermore, in the medical device 10 of this embodiment, the cross-section of the metal wire constituting the digging section 200, located at a position closer to the front end than the position where the width in the Y-axis direction of the digging section 200 reaches its maximum value, has a straight surface facing the outer side of the ring shape. Therefore, forming an edge at the edge of the digging section 200 in the direction of rotation of the digging section 200 more effectively improves the digging performance of the medical device 10 on the lesion 32. Moreover, the cross-section of the metal wire constituting the digging section 200 at the position where the width in the Y-axis direction of the digging section 200 reaches its maximum value is circular. Therefore, the risk of the medical device 10 digging into the wall of the lesion 32 can be reduced.

[0056] B. Variations:

[0057] The technology disclosed in this specification is not limited to the above-described embodiments, and can be modified in various ways without departing from its spirit, for example, the following modifications are also possible.

[0058] Figure 10This is an explanatory diagram showing the detailed structure of the excavation section 200a in the modified example. Figure 10 The image shows an enlarged view of the front end of the medical device 10a when viewed along the X-axis. Hereinafter, structures in the modified medical device 10a that are identical to those in the medical device 10 of the above-described embodiment will be labeled with the same reference numerals, and their descriptions will be omitted as appropriate.

[0059] The structure of the excavation section 200a constituting the modified medical device 10a differs from that of the excavation section 200 in the embodiment. Specifically, the excavation section 200a in the modified example is not ring-shaped, but paddle-shaped. That is, the excavation section 200a in the modified example has a structure in which the through hole 210 in the excavation section 200 of the embodiment is filled. Thus, the excavation section of the medical device does not necessarily have to be ring-shaped, as long as it is at least flat. In addition, as Figure 10 As shown, the excavation part 200a in the modified example is a paddle-shaped part with a flat surface facing the X-axis direction, but the excavation part may also be a spoon-shaped part with a depression near the center of the surface facing the X-axis direction.

[0060] In the above embodiments, the inner coil body 400 is composed of multiple coils with multiple wires wound around them. However, the inner coil body may not consist of multiple coils, but rather a single coil with one wire wound around it. Furthermore, in the above embodiments, each wire constituting the inner coil body 400 is a single wire, but each wire constituting the inner coil body may also be a stranded wire composed of multiple wires twisted together. Additionally, in the above embodiments, the inner coil body 400 is a single-layer coil composed of one layer, but the inner coil body may also be a multi-layer coil composed of multiple layers.

[0061] In the above embodiment, the excavating part 200 is configured to be in a contracted state and an expanded state, but the shape of the excavating part does not necessarily need to be changed. Similarly, the excavating part does not necessarily have to be made of a hyperelastic material.

[0062] The shape of the cross-section of the metal wire constituting the excavation section 200 in the above embodiment is just one example, and various modifications are possible. For example, the cross-section of the metal wire constituting the excavation section may be rectangular or circular from one end to the other. In addition, the shapes of the outer and inner portions of the ring shape may be different; for example, the outer surface of the ring shape may be arc-shaped, and the inner surface may be rectangular from one end to the other.

[0063] In the above embodiment, guide wire 20 is used as a guiding component, but other guiding components besides guide wire may also be used.

[0064] In the above embodiments, the medical device 10 is used for the treatment of lesions within blood vessels, but the technology disclosed in this specification can also be applied to the lumens of organisms outside blood vessels (such as bile ducts, gallbladders, pancreas, esophagus, duodenum, small intestine, large intestine, blood vessels, ureters, trachea, etc.).

Claims

1. A medical device (10), characterized in that, have: The tube (100) has a lumen (102) for inserting the guide member (20); and The excavation section (200) protrudes forward from the front end of the tube (100), and the maximum value of its width in a first direction orthogonal to the central axis (AX2) of the tube (100) is greater than the maximum value of its width in a second direction orthogonal to both the central axis (AX2) and the first direction. The front end of the excavation section (200) is positioned on one side of the tube (100) in the second direction.

2. The medical device (10) according to claim 1, characterized in that, The excavation section (200) is configured to be in a contracted state and an expanded state that expands in the first direction compared to the contracted state.

3. The medical device (10) according to claim 2, characterized in that, The excavation section (200) is made of a superelastic material and has a ring shape.

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