Foreign object removal device

Abstract

To provide a foreign object removal device which suppresses a damage of an outer tube and is convenient.SOLUTION: The foreign object removal device comprises: an inner tube, an outer tube disposed surrounding the periphery of the inner tube; and a tubular expansion body disposed between the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube. The expansion body can change relative positions with respect to the inner tube and the outer tube by sliding and moving in an axial direction of the foreign object removal device.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a foreign body removal device. [Background technology]

[0002] There is known a device that physically removes foreign bodies such as thrombi that block blood vessels. For example, Patent Document 1 discloses a suction catheter that includes an outer tube and an inner tube. In the device described in Patent Document 1, an elastically deformable part is provided at the tip of the inner tube, and when the entire inner tube including the elastically deformable part is housed in the outer tube, the elastically deformable part is pressed against the outer tube and in a contracted state, and when the inner tube protrudes from the outer tube, the elastically deformable part is in an expanded state, making it possible to remove foreign bodies. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-66178 A Summary of the Invention [Problem to be solved by the invention]

[0004] In a device for removing foreign bodies such as thrombi, the elastically deformable part expands in an expanded state to an outer diameter substantially equal to the inner diameter of the blood vessel in order to remove all foreign bodies from the blood vessel. In this regard, in the device described in the cited document 1, since the elastically deformable part is provided at the tip of the inner tube, the elastically deformable part needs to expand from an outer diameter equal to the outer diameter of the inner tube to an outer diameter equal to the inner diameter of the blood vessel. Here, when the tip of the device is delivered to a lesion where a foreign body such as a thrombus is present, the elastically deformable part is in a contracted state and is housed in the outer tube together with the inner tube. At this time, the elastically deformable part in the contracted state is pressed by the inner wall (inner peripheral surface) of the outer tube and compressed to an outer diameter equal to or smaller than the inner diameter of the outer tube.

[0005] As described above, in the device described in Patent Document 1, the expansion width of the elastically deformable part (in other words, the difference in the outer diameter before and after the expansion of the elastically deformable part) is "the inner diameter of the blood vessel - the outer diameter of the inner tube", so the elastically deformable part needs to have a high expansion force. When the inner tube is protruded from the outer tube to expand the elastically deformable part, the elastically deformable part has a problem that the sliding resistance between the inner wall (inner peripheral surface) of the outer tube increases, leading to deformation of the outer tube, damage to the inner wall of the outer tube, and reduced operability. Note that this problem is not limited to the case where the elastically deformable part expands to the inner diameter of the blood vessel, but is common to all cases where the elastically deformable part expands to any outer diameter larger than the outer tube. In addition, this problem is not limited to the vascular system, but is common to all devices that remove foreign bodies from various organs in the human body, such as the lymphatic system, biliary system, urinary system, respiratory system, digestive system, secretory glands, and reproductive organs.

[0006] The present invention has been made to solve the above-mentioned problems, and has an object to prevent damage to an outer tube in a foreign body removal device and to improve ease of use. [Means for solving the problem]

[0007] The present invention has been made to solve at least part of the above-mentioned problems, and can be realized in the following forms.

[0008] (1) According to one aspect of the present invention, there is provided a foreign body removal device comprising an inner tube, an outer tube arranged to surround the periphery of the inner tube, and a cylindrical expandable body arranged between an outer circumferential surface of the inner tube and an inner circumferential surface of the outer tube, the expandable body being capable of changing its relative position with respect to the inner tube and the outer tube by sliding in the axial direction of the foreign body removal device.

[0009] According to this configuration, the expansion body is disposed between the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube, so that the expansion width of the expansion body (in other words, the difference between the outer diameters of the expansion body before and after expansion) can be set to "the outer diameter of the expansion body in the expanded state - the outer diameter of the expansion body in the contracted state". Here, the outer diameter of the expansion body in the expanded state is, for example, the inner diameter of a blood vessel. Also, the outer diameter of the expansion body in the contracted state is, for example, any outer diameter that is larger than the outer diameter of the inner tube and smaller than the inner diameter of the outer tube. Thus, in this configuration, the expansion width of the expansion body can be made smaller than when the expansion body is provided at the tip of the inner tube, so that the expansion force of the expansion body can be designed to be weaker than when the expansion body is provided at the tip of the inner tube. As a result, according to this configuration, the sliding resistance between the expansion body and the inner wall (inner peripheral surface) of the outer tube when the expansion body is slid can be reduced, so that deformation of the outer tube and damage to the inner wall of the outer tube can be suppressed, and the operability of the foreign body removal device can be improved by reducing the force required for sliding the expansion body.

[0010] (2) In the foreign body removal device of the above configuration, the expansion body may slide between a first position in which both the tip and base ends of the expansion body are located closer to the base end than the tip of the outer tube, and a second position in which the tip of the expansion body is located closer to the tip of the outer tube and the base end of the expansion body is located closer to the base end than the tip of the outer tube. According to this configuration, the expansion body slides between a first position and a second position. At the first position, both the distal end and the proximal end of the expansion body are located proximal to the distal end of the outer tube, so that the expansion body can be in a contracted state. At the second position, the distal end of the expansion body is located distal to the distal end of the outer tube, so that the distal side of the expansion body can be in an expanded state in which it is expanded. At the second position, the proximal end of the expansion body is located proximal to the distal end of the outer tube, so that the expansion body that slides to the second position can be prevented from falling off from the distal side of the outer tube.

[0011] (3) In the foreign body removal device of the above-described embodiment, a ring-shaped support member may be provided between an outer peripheral surface of the inner tube and an inner peripheral surface of the outer tube, closer to the base end than the expandable body. According to this configuration, a ring-shaped support member is provided between the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube, and on the base end side of the expansion body. Therefore, by supplying a working fluid between the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube from the base end side of the foreign body removal device and applying pressure (positive pressure) to the support member, a force toward the tip side from the support member to the expansion body can be applied, and the expansion body can be slid toward the tip end side. Similarly, by removing the supplied working fluid and applying negative pressure to the support member, a force toward the base end from the support member to the expansion body can be applied, and the expansion body can be slid toward the base end side. That is, the support member can be used to slide the expansion body in the axial direction of the foreign body removal device. Furthermore, according to this configuration, it is possible to further suppress the expansion body that has slid to the second position from falling off the tip side of the outer tube.

[0012] (4) In the foreign body removal device of the above-described form, the tip of the inner tube is located more distal than the tip of the outer tube, and the outer surface of the inner tube may have a raised portion protruding outward from the tip of the outer tube, on the outer surface of the inner tube more distal than the tip of the outer tube. According to this configuration, the tip of the inner tube is located more distal than the tip of the outer tube, and a protuberance is provided on the outer peripheral surface of the inner tube more distal than the tip of the outer tube. The protuberance allows the expandable body to be smoothly guided to the expanded state when the expandable body slides from the first position to the second position. The protuberance also prevents foreign matter, such as a captured blood clot, from entering between the tip of the inner tube (the portion protruding from the outer tube) and the inside of the expandable body in the expanded state. The expandable body in the expanded state is also more easily arranged coaxially with the inner tube and the outer tube.

[0013] The present invention can be realized in various aspects, for example, in the form of a foreign body removal device, a catheter equipped with an expandable body for removing foreign bodies, and a manufacturing method thereof. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is an explanatory diagram showing an overall configuration of a foreign body removal device according to a first embodiment. [Diagram 2] FIG. 2 is an enlarged longitudinal cross-sectional view of the distal end side of the foreign body removal device. [Diagram 3] 3 shows a cross-sectional view taken along line AA in FIG. 2. [Figure 4] FIG. 2 shows an enlarged longitudinal cross-sectional view of the proximal end side of the foreign body removal device. [Diagram 5] FIG. 13 is a diagram illustrating an extension body. [Figure 6] 1A and 1B are diagrams illustrating a state in which foreign matter is removed by a foreign matter removal device. [Figure 7] FIG. 11 is an explanatory diagram illustrating the configuration of a foreign matter removal device according to a second embodiment. [Figure 8] FIG. 13 is an explanatory diagram illustrating the configuration of a foreign matter removal device according to a third embodiment. [Figure 9] FIG. 13 is an explanatory diagram illustrating the configuration of a foreign matter removal device according to a fourth embodiment. [Figure 10] FIG. 13 is an explanatory diagram illustrating the configuration of a foreign matter removal device according to a fifth embodiment. [Figure 11] FIG. 13 is an explanatory diagram illustrating the configuration of a foreign matter removal device according to a sixth embodiment. [Figure 12] FIG. 13 is an explanatory diagram illustrating the configuration of a foreign matter removal device according to a seventh embodiment. [Figure 13] FIG. 13 is an explanatory diagram illustrating the configuration of a foreign matter removal device according to an eighth embodiment. [Figure 14] FIG. 13 is an explanatory diagram illustrating the configuration of a foreign matter removal device according to a ninth embodiment. [Figure 15] 13 is an explanatory diagram illustrating the configuration of a foreign matter removal device according to a modified example. FIG. [Figure 16]13 is an explanatory diagram illustrating the configuration of a foreign matter removal device according to a modified example. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] First Embodiment FIG. 1 is an explanatory diagram showing the overall configuration of a foreign body removal device 1 of a first embodiment. The foreign body removal device 1 is a medical device used to physically remove foreign bodies such as thrombi that block blood vessels. The foreign body removal device 1 can be configured as a device for removing objects (foreign bodies) in biological lumens such as blood vessels including cardiovascular and cerebral blood vessels, lymphatic system, biliary system, urinary system, respiratory system, digestive system, secretory glands, and reproductive organs. The foreign body removal device 1 has a tube 10, an expandable body 20 provided on the tip side of the tube 10, and a connector 30 provided on the base end side of the tube 10. FIG. 1 illustrates an expanded state in which the expandable body 20 is expanded.

[0016] In FIG. 1, the axis passing through the center of the foreign body removal device 1 is represented by the axis O (dotted line). In the example of FIG. 1, the axis O coincides with the axis passing through the center of the tube 10 and the expansion body 20. However, the axis O may differ from the central axis of the tube 10 and the expansion body 20. FIG. 1 also illustrates mutually orthogonal XYZ axes. The X axis corresponds to the longitudinal direction of the foreign body removal device 1, the Y axis corresponds to the height direction of the foreign body removal device 1, and the Z axis corresponds to the width direction of the foreign body removal device 1. The right side (+X axis direction) of FIG. 1 is called the "tip side" of the foreign body removal device 1 and each component, and the left side (-X axis direction) of FIG. 1 is called the "base side" of the foreign body removal device 1 and each component. In addition, of both ends in the longitudinal direction (X axis direction) of the foreign body removal device 1 and each component, one end located on the tip side is called the "tip" and the other end located on the base side is called the "base end". The tip and its vicinity are called the "tip portion," and the base end and its vicinity are called the "base end portion." The tip side is inserted into the living body, and the base end side is operated by a surgeon such as a doctor. These points are the same in Figure 1 and subsequent figures.

[0017] Fig. 2 shows a longitudinal cross-sectional view of an enlarged distal end of the foreign body removal device 1. Fig. 3 shows a transverse cross-sectional view taken along line AA in Fig. 2. Figs. 2 and 3 show a contracted state in which the expandable body 20 is contracted. The tube 10 includes an outer tube 11 and an inner tube 12 that extend along the axial direction of the foreign body removal device 1. Both the outer tube 11 and the inner tube 12 are cylindrical (in other words, tubular) members that have openings at the distal end and the proximal end and have an inner lumen inside.

[0018] As shown in FIG. 2, the outer tube 11 is disposed outside the inner tube 12 and surrounds the inner tube 12. In the example of FIG. 2, the tip 111 of the outer tube 11 and the tip 121 of the inner tube 12 are located at approximately the same position in the axial direction of the foreign body removal device 1. The tip of the outer tube 11 is provided with a reduced diameter section 113 (a portion surrounded by a dashed line frame in FIG. 2) in which both the outer diameter and the inner diameter of the outer tube 11 are reduced from the base end side toward the tip end side. On the base end side of the reduced diameter section 113, the outer diameter and the inner diameter of the outer tube 11 are approximately constant. As shown in FIG. 3, a reinforcing body 119 is embedded in the thick part of the outer tube 11. The reinforcing body 119 is a cylindrical (in other words, tubular) braided body.

[0019] The inner tube 12 is disposed in the lumen of the outer tube 11. A base end stopper 123 is provided at an arbitrary position on the outer circumferential surface 12a of the inner tube 12 that is closer to the base end than the tip 121 of the inner tube 12. The base end stopper 123 is a part having a convex shape in which a part of the thickness of the inner tube 12 rises from the outer circumferential surface 12a of the inner tube 12 toward the inner circumferential surface 11b of the outer tube 11. Except for the part where the base end stopper 123 is provided, the outer diameter and the inner diameter of the inner tube 12 are approximately constant. As shown in FIG. 3, a reinforcing body 129 is embedded in the thick part of the inner tube 12. The reinforcing body 129 is a cylindrical (in other words, tubular) braided body.

[0020] As shown in Fig. 3, the outer diameter Φ1 of the inner tube 12 is smaller than the inner diameter Φ3 of the outer tube 11. Therefore, an outer lumen 11L through which a fluid can flow is formed between the inner peripheral surface 11b of the outer tube 11 and the outer peripheral surface 12a of the inner tube 12. The outer lumen 11L is a lumen formed between the outer tube 11 and the inner tube 12 of the double-tube structure, and therefore has a cylindrical shape as shown in Fig. 3. Moreover, an inner lumen 12L through which a fluid can flow is formed inside the inner tube 12. The inner lumen 12L is a lumen formed inside the inner tube 12, and therefore has a cylindrical shape as shown in Fig. 3.

[0021] Fig. 4 shows a longitudinal cross-sectional view of the foreign body removal device 1 with the base end side enlarged. In Fig. 4, the connector 30 is illustrated as a cross-sectional view, and the outer tube 11 and the inner tube 12 are illustrated as overview views. The lower part of Fig. 4 shows an enlarged view of the vicinity of the base end of the inner tube 12. As shown in Fig. 4, at the base end side of the foreign body removal device 1, a part of the base end side of the inner tube 12 protrudes from the base end 112 of the outer tube 11. The connector 30 has a first extension part 31 and a second extension part 32 that extend into two branches.

[0022] The first extension portion 31 is a portion that extends in the extension direction of the tube 10 (the outer tube 11 and the inner tube 12), in other words, along the axial direction of the foreign body removal device 1. An aspiration lumen 31L (inner cavity) is formed inside the first extension portion 31. The diameter of the aspiration lumen 31L gradually decreases from the base end side toward the tip end side. In the vicinity of the center of the aspiration lumen 31L, as shown in the enlarged view at the bottom of FIG. 4, a step portion 34 is formed by expanding the inner diameter of the aspiration lumen 31L. In other words, the step portion 34 is a portion where the inner wall of the connector 30 is stepped. The base end 122 of the inner tube 12 abuts against the step portion 34, thereby fixing the inner tube 12. With this configuration, the suction lumen 31L and the inner lumen 12L are communicated with each other, allowing fluid to flow from the inner lumen 12L to the suction lumen 31L, while preventing fluid from straying from the suction lumen 31L to the outer lumen 11L. A first opening 311 and a first fitting portion 312 are formed at the base end of the first extension portion 31. The first opening 311 is an opening that communicates the suction lumen 31L with the outside. The first fitting portion 312 is a portion having a screw structure to which a syringe, a suction device, or the like can be attached.

[0023] The second extension portion 32 is a portion extending along a direction intersecting the extension direction of the tube 10. A lumen 32L (inner cavity) is formed inside the second extension portion 32. The lumen 32L gradually reduces in diameter from the base end side toward the tip end side. The tip end of the lumen 32L communicates with a cylindrical space (inner cavity) formed between the inner wall of the connector 30 on the tip side of the step portion 34 and the outer circumferential surface of the inner tube 12 protruding from the outer tube 11. With this configuration, the lumen 32L communicates with the outer lumen 11L, allowing the passage of a fluid from the lumen 32L to the outer lumen 11L. A second opening 321 and a second fitting portion 322 are formed at the base end of the second extension portion 32. The second opening 321 is an opening that communicates the lumen 32L with the outside. The second fitting portion 322 is a portion having a threaded structure to which a syringe or the like can be attached.

[0024] The distal end of the connector 30 is provided with a locking portion 33 that grips and fixes the proximal end of the outer tube 11. As described above, the inner tube 12 is fixed by abutting the proximal end 122 against the step portion 34. That is, in this embodiment, the outer tube 11 and the inner tube 12 are fixed to each other by the connector 30. The outer tube 11 and the inner tube 12 may be fixed by being bonded with any bonding agent such as an epoxy adhesive.

[0025] Fig. 5 is a diagram for explaining the expandable body 20. Fig. 5(A) shows the state in which the expandable body 20 transitions from a contracted state to an expanded state. Fig. 5(B) shows the expandable body 20 in the expanded state. The lower part of Fig. 5(B) shows an enlarged view of the vicinity of the tip of the inner tube 12 and the outer tube 11. Note that Fig. 2 mentioned above shows the expandable body 20 in the contracted state.

[0026] The expandable body 20 is disposed between the outer peripheral surface 12a of the inner tube 12 and the inner peripheral surface 11b of the outer tube 11. The expandable body 20 has an expandable portion 21 and a support member 22. The expandable portion 21 of the expandable body 20 is a mesh-like braided body made of wires woven in a mesh pattern, and is a member having a cylindrical shape (in other words, a tubular shape). The size of the opening of the wires of the expandable portion 21 can be determined arbitrarily, but in order to obtain the blood flow blocking effect described later, it is preferable that the size of the opening is large enough to block or weaken the flow of fluid. The expandable portion 21 of the expandable body 20 is elastically deformable and is biased to expand from the contracted state shown in FIG. 2 to the expanded state shown in FIG. 5(B). In other words, the expandable portion 21 of the expandable body 20 can be said to be a self-expanding mesh body. As shown in FIG. 3, the expansion portion 21 of the expansion body 20 has an outer diameter Φ2 that is larger than the outer diameter Φ1 of the inner tube 12 and smaller than the inner diameter Φ3 of the outer tube 11 in a contracted state.

[0027] The support member 22 of the expansion body 20 is disposed between the outer peripheral surface 12a of the inner tube 12 and the inner peripheral surface 11b of the outer tube 11, similarly to the expansion section 21. The support member 22 is an annular member fixed to the base end of the expansion section 21 (the base end of the expansion body 20). The annular shape includes a "substantially annular shape" such as a C-shape in which a portion in the circumferential direction is open, rather than a complete annular shape. The expansion section 21 and the support member 22 of the expansion body 20 may be integrally formed or may be configured as separate members. The expansion section 21 and the support member 22 may be formed of the same material or different materials. For example, the expansion section 21 may be formed of a metal material, and the support member 22 may be formed of a resin material.

[0028] In the contracted state of the expansion body 20, as shown in FIG. 2, the entire expansion body 20 (in other words, both the distal end 211 and the proximal end 212 of the expansion body 20) is located on the proximal side of the distal end 111 of the outer tube 11. In other words, in the contracted state, the entire expansion body 20 is accommodated in the outer lumen 11L. In the contracted state, the support member 22 of the expansion body 20 abuts against the proximal end stopper 123 of the inner tube 12, thereby suppressing the support member 22 from moving proximally beyond the proximal end stopper 123. In other words, in the contracted state, the support member 22 and the proximal end stopper 123 restrict further movement of the expansion body 20 toward the proximal end side. At this time, the retracted length of the expansion body 20 (in other words, the length from the distal end 111 of the outer tube 11 to the distal end 211 of the expansion body 20) is L1. The retracted length L1 of the expansion body 20 can be determined arbitrarily. The position of the expandable body 20 when both the distal end 212 and the proximal end 212 of the expandable body 20 are located on the proximal side of the distal end 111 of the outer tube 11 is referred to as the "first position." Figure 2 shows the expandable body 20 located in the first position.

[0029] In the expanded state of the expandable body 20, as shown in FIG. 5(B), the tip 211 of the expandable body 20 is located on the tip side of the tip 111 of the outer tube 11, and the support member 22 provided at the base end of the expandable body 20 is located on the base end side of the tip 111 of the outer tube 11. In other words, in the expanded state, a part of the tip side of the expandable body 20 protrudes to the outside from the outer lumen 11L, and a part of the base end side of the expandable body 20 is accommodated in the outer lumen 11L. In the expanded state, the support member 22 of the expandable body 20 abuts against the inner surface of the reduced diameter portion 113 of the outer tube 11, thereby suppressing the support member 22 from moving distally beyond the reduced diameter portion 113. In other words, in the expanded state, the support member 22 and the reduced diameter portion 113 restrict further movement of the expandable body 20 toward the tip side, thereby suppressing the expansion body 20 from falling off from the tip side of the outer tube 11. The position of the expansion body 20 when the tip 211 of the expansion body 20 is located further distal than the tip 111 of the outer tube 11 and the base end 212 of the expansion body 20 is located further proximal than the tip 111 of the outer tube 11 is referred to as the "second position." Figure 5(B) shows the expansion body 20 located in the second position.

[0030] In use, the foreign body removal device 1 is inserted into a blood vessel with the expansion body 20 in the contracted state shown in FIG. 2 (in other words, the expansion body 20 in the first position) and delivered to a lesion where a foreign body such as a thrombus is present. After delivering the tip of the foreign body removal device 1 to the lesion, the surgeon attaches a syringe or the like filled with a working fluid (e.g., saline solution, air, etc.) to the second fitting portion 322 of the connector 30 and supplies the working fluid from the second opening 321. The working fluid supplied from the second opening 321 flows into the outer lumen 11L via the lumen 32L. As the surgeon continues to supply the working fluid, the outer lumen 11L is filled with the working fluid as shown in FIG. 5(A), and pressure (positive pressure) is applied to the support member 22 of the expansion body 20. As a result, a force toward the distal end is applied from the support member 22 to the expansion body 20, and as shown by the white arrow in Fig. 5(A), the expansion body 20 slides toward the distal end along the axial direction of the foreign body removal device 1. As the expansion body 20 slides in the axial direction of the foreign body removal device 1, the relative position of the expansion body 20 and the outer tube 11 is changed, and the relative position of the expansion body 20 and the inner tube 12 is also changed. The expansion body 20 moves toward the distal end until the support member 22 abuts against the reduced diameter portion 113, as described in Fig. 5(B).

[0031] The expansion section 21 of the expansion body 20 is elastically deformable and is biased to expand from a contracted state to an expanded state. As shown in Figs. 5(A) and (B), the portion of the expansion section 21 of the expansion body 20 located on the distal side of the distal end 111 of the outer tube 11 (in other words, the portion protruding from the outer lumen 11L to the outside) is not compressed by the outer tube 11, and therefore has an expanded outer diameter. The foreign body removal device 1 is used to remove foreign bodies constituting a lesion when the expansion body 20 is in the expanded state shown in Fig. 5(B) (in other words, the state in which the expansion body 20 is in the second position). In the expansion section 21 of the expansion body 20, in the expanded state shown in Fig. 5(B), a portion 21b protruding from the outer lumen 11L to the outside and located on the outer tube 11 side has a tapered shape that gradually expands in diameter from the base end side toward the distal end side. On the other hand, of the expansion portion 21 of the expansion body 20, in the expanded state shown in Figure 5 (B), the tip portion 21a that protrudes outward from the outer lumen 11L and is located on the side farther from the outer tube 11 (i.e., the tip side) has a cylindrical shape with an approximately constant outer diameter.

[0032] FIG. 6 is a diagram showing a state in which a foreign body is removed by the foreign body removal device 1. In addition to the foreign body removal device 1, FIG. 6 shows a blood vessel 91, a foreign body 92 such as a thrombus blocking the blood vessel 91, and a foreign body 93 such as a thrombus being collected by the foreign body removal device 1. The foreign body removal device 1 is delivered to the position of the foreign body 92 along a guide wire, a microcatheter, or the like, which has been inserted into the blood vessel 91 in advance. After the tip of the foreign body removal device 1 reaches the position of the foreign body 92, the expandable body 20 is put into the expanded state by the above-mentioned procedure (FIG. 6 shows the expandable body 20 in the expanded state). In the example of this embodiment, the outer diameter of the largest tip side portion 21a of the expandable body 20 in the expanded state is approximately equal to the inner diameter of the blood vessel 91.

[0033] Here, in FIG. 6, the direction of blood flow in the blood vessel 91 is indicated by a black arrow BF. As shown in the figure, the distal end portion 21a of the expandable body 20 expands to an outer diameter substantially equal to the inner diameter of the blood vessel 91 in the expanded state to block the blood flow BF, so that the foreign bodies 92, 93 can be prevented from being carried from the lesion to the downstream side of the blood flow BF by the blood flow BF. In the state shown in FIG. 6, the surgeon attaches a device for sucking thrombi (e.g., a syringe, a suction device, etc.) to the first fitting portion 312 of the connector 30 and applies negative pressure. As a result, the foreign bodies 92, 93 in the blood vessel 91 are sucked from the distal end opening 201 of the expandable body 20 to the inside of the expansion portion 21 of the expandable body 20, and are collected into the inside of the device for sucking thrombi via the inner lumen 12L and the suction lumen 31L. In this way, since the expandable body 20 blocks the blood flow BF, the blood flow BF is less likely to be drawn into the lumen 12L. Therefore, sufficient negative pressure is applied to the foreign bodies 92, 93, so that the foreign bodies 92, 93 can be more reliably removed.

[0034] After collecting the foreign body, the surgeon aspirates the working fluid in the outer lumen 11L using a syringe or the like attached to the second fitting portion 322 of the connector 30. As the surgeon continues to aspirate the working fluid, negative pressure is applied to the support member 22 of the expansion body 20. This applies a force from the support member 22 to the expansion body 20 toward the base end, and the expansion body 20 slides toward the base end along the axial direction of the foreign body removal device 1. As described in FIG. 2, the expansion body 20 moves toward the base end until the support member 22 abuts against the base end stopper 123. In this way, the expansion body 20 of this embodiment is not fixed to the tube 10 (in other words, it is not fixed to either the outer tube 11 or the inner tube 12), and can freely change between a contracted state and an expanded state by sliding within the outer lumen 11L.

[0035] The outer tube 11 and the inner tube 12 are preferably antithrombotic, flexible, and biocompatible, and can be made of a resin material or a metal material. Examples of the resin material that can be used include polyamide resin, polyolefin resin, polyester resin, polyurethane resin, silicone resin, and fluororesin. Examples of the metal material that can be used include stainless steel such as SUS304, nickel-titanium alloy, and cobalt-chrome alloy. The reinforcing body 119 and the reinforcing body 129 can be made of any metal material such as stainless steel such as SUS304, nickel-titanium alloy, and cobalt-chrome alloy.

[0036] The expansion part 21 and the support member 22 of the expansion body 20 are formed of a metal material or a resin material. For example, stainless steel such as SUS304, nickel titanium alloy, cobalt chrome alloy, etc. can be used as the metal material. If radiopaque materials such as gold, platinum, tungsten, or alloys containing these elements are used as the material of the expansion part 21, the visibility of the expansion part 21 under X-ray fluoroscopy can be improved. For example, polyamide, polyester, polyacrylate, polyether ether ketone, etc. can be used as the resin material. Note that the support member 22 may be made of natural rubber or synthetic rubber, but it is preferable that the support member 22 is made of a material that has low friction resistance between the tube 10 (the outer tube 11 and the inner tube 12). The connector 30 can be made of, for example, polyamide, polyester, polyurethane, fluororesin such as polytetrafluoroethylene (PTFE), or other known resin materials.

[0037] As described above, according to the foreign body removal device 1 of the first embodiment, the expandable body 20 is disposed between the outer peripheral surface 12a of the inner tube 12 and the inner peripheral surface 11b of the outer tube 11, and therefore the expansion width of the expandable body 20, in other words, the difference in the outer diameter of the expandable body 20 before and after expansion, can be defined as "the outer diameter of the expandable body in the expanded state - the outer diameter of the expandable body in the contracted state". Here, the outer diameter of the expandable body in the expanded state is, for example, the outer diameter of the tip side portion 21a which is equal to the inner diameter of the blood vessel 91 shown in FIG. 6. Also, the outer diameter of the expandable body in the contracted state is, for example, an arbitrary outer diameter Φ2 which is larger than the outer diameter Φ1 of the inner tube 12 shown in FIG. 3 and smaller than the inner diameter Φ3 of the outer tube 11 shown in FIG. 3. Thus, in the foreign body removal device 1 of this embodiment, the expansion width of the expandable body 20 can be reduced by Φ2 - Φ1, compared to when the expandable body is provided at the tip of the inner tube (in other words, when the outer diameter of the expandable body = Φ1). Therefore, the expansion force of the expansion body 20 can be designed to be weaker than when the expansion body is provided at the tip of the inner tube. As a result, according to the foreign body removal device 1 of this embodiment, the sliding resistance between the expansion body 20 and the inner wall (inner circumferential surface 11b) of the outer tube 11 when the expansion body 20 is slid can be reduced, so that deformation of the outer tube 11 and damage to the inner wall of the outer tube 11 can be suppressed, and the operability of the foreign body removal device 1 can be improved by reducing the force required for the sliding movement of the expansion body 20.

[0038] According to the foreign body removal device 1 of the first embodiment, the expansion body 20 slides between a first position shown in FIG. 2 and a second position shown in FIG. 5(B). At the first position, both the distal end 211 and the proximal end 212 of the expansion body 20 are located on the proximal side of the distal end 111 of the outer tube 11, so that the expansion body 20 can be contracted by pressing the outer tube 11. At the second position, the distal end 211 of the expansion body 20 is located on the distal side of the distal end 111 of the outer tube 11, so that the distal end side of the expansion body 20 can be expanded to an expanded state. At the second position, the proximal end (support member 22) of the expansion body 20 is located on the proximal side of the distal end 111 of the outer tube 11, so that the expansion body 20 that slides to the second position can be prevented from falling off from the distal end side of the outer tube 11.

[0039] Furthermore, according to the foreign body removal device 1 of the first embodiment, a ring-shaped support member 22 is provided between the outer peripheral surface 12a of the inner tube 12 and the inner peripheral surface 11b of the outer tube 11 at the base end of the expansion body 20. Therefore, as shown in FIG. 5(A), by supplying a working fluid from the base end side of the foreign body removal device 1 to between the outer peripheral surface 12a of the inner tube 12 and the inner peripheral surface 11b of the outer tube 11 (outer lumen 11L) and applying pressure (positive pressure) to the support member 22, a force toward the distal end side is applied from the support member 22 to the expansion body 20, and the expansion body 20 can be slid toward the distal end side. Similarly, by removing the supplied working fluid and applying negative pressure to the support member 22, a force toward the proximal end side is applied from the support member 22 to the expansion body 20, and the expansion body 20 can be slid toward the proximal end side. That is, the support member 22 can be used to slide the expansion body 20 in the axial direction of the foreign body removal device 1. In addition, by the support member 22 getting caught on the reduced diameter portion 113 provided at the tip of the outer tube 11, the expansion body 20, which has slid to the second position, can be further prevented from falling off from the tip side of the outer tube 11.

[0040] Furthermore, according to the foreign body removal device 1 of the first embodiment, the outer tube 11 and the inner tube 12 have a double tube structure fixed to each other by the connector 30. Therefore, the usability of the foreign body removal device 1 can be improved compared to a case where a first device having an expansion body at its tip is used in combination with a second device that covers the first device to suppress the expansion of the expansion body and serves as a guide for delivering the first device to the lesion. In addition, compared to a case where the first device and the second device are used in combination, the constraints on the outer diameter of the foreign body removal device 1 (particularly the outer diameter of the tube 10) can be reduced. In detail, since the expansion force of the expansion body 20 can be suppressed, the thickness of the outer tube 11 that houses the expansion body 20 in a contracted state can be made thin.

[0041] <Second embodiment> Fig. 7 is an explanatory diagram illustrating the configuration of a foreign body removal device 1A of a second embodiment. Fig. 7 is an enlarged longitudinal sectional view of the distal end side of the foreign body removal device 1A when the expandable body 20 is in a contracted state. The foreign body removal device 1A includes a tube 10A instead of the tube 10 in the configuration of the first embodiment. The tube 10A includes an inner tube 12A instead of the inner tube 12.

[0042] The inner tube 12A differs from the inner tube 12 in that the position where the base end stopper 123A is formed is further toward the base end side (in the -X axis direction) than in the first embodiment shown in Fig. 2. As a result, in the foreign body removal device 1A, the retracted length L1A of the expandable body 20 (in other words, the length L1A from the tip 111 of the outer tube 11 to the tip 211 of the expandable body 20) is longer than in the first embodiment shown in Fig. 2. Here, the rigidity of the tube 10A is increased by the amount of the expandable body 20 in the portion where the expandable body 20 is housed in the outer lumen 11L. In this regard, in the foreign body removal device 1A, the retracted length L1A of the expandable body 20 is longer, thereby making it possible to make the tip portion of the tube 10A flexible.

[0043] In this way, the configuration of the tube 10A can be modified in various ways, and the base end stopper 123A can be formed at any position. The foreign body removal device 1A of the second embodiment as described above can also achieve the same effects as those of the first embodiment.

[0044] <Third embodiment> Fig. 8 is an explanatory diagram illustrating the configuration of a foreign body removal device 1B of a third embodiment. Fig. 8 is an enlarged longitudinal sectional view of the distal end side of the foreign body removal device 1B when the expandable body 20 is in a contracted state. The foreign body removal device 1B includes a tube 10B instead of the tube 10 in the configuration of the first embodiment. The tube 10B includes an outer tube 11B instead of the outer tube 11, and an inner tube 12B instead of the inner tube 12.

[0045] The outer tube 11B has a base end stopper 114 instead of the reduced diameter portion 113 (FIG. 2). The base end stopper 114 is a part having a convex shape in which a part of the wall thickness of the outer tube 11B rises from the inner circumferential surface 11b of the outer tube 11B toward the outer circumferential surface 12a of the inner tube 12B. The base end stopper 114 is provided at the same position as the base end stopper 123 (FIG. 2) in the axial direction of the foreign body removal device 1B. The base end stopper 114 abuts against the support member 22 of the expansion body 20, thereby restricting the expansion body 20 in the contracted state from moving further toward the base end side. That is, the base end stopper 114 has the same function as the base end stopper 123 (FIG. 2) of the first embodiment.

[0046] The inner tube 12B has a tip stopper 124 instead of the base end stopper 123 (FIG. 2). The tip stopper 124 is a part having a convex shape in which a part of the wall thickness of the inner tube 12B rises from the outer peripheral surface 12a of the inner tube 12B toward the inner peripheral surface 11b of the outer tube 11B. The tip stopper 124 is provided at the same position as the reduced diameter portion 113 (FIG. 2) in the axial direction of the foreign body removal device 1B, in other words, at the tip of the outer tube 11B. The tip stopper 124 abuts against the support member 22 of the expandable body 20, thereby restricting the expandable body 20 in the expanded state from moving further toward the tip side. That is, the tip stopper 124 has the same function as the reduced diameter portion 113 (FIG. 2) of the first embodiment.

[0047] In this way, the configuration of the tube 10B can be modified in various ways, and the portion that restricts the sliding movement of the expansion body 20 by abutting the support member 22 of the expansion body 20 may be provided on either the outer tube 11B or the inner tube 12B. The portion that restricts the sliding movement of the expansion body 20 may be configured by reducing the outer diameter and inner diameter of the outer tube 11 (or the inner tube 12) like the reduced diameter section 113 (FIG. 2) of the first embodiment, or may be configured by padding the outer tube 11B (or the inner tube 12B) like this embodiment. The foreign body removal device 1B of the third embodiment as described above can also achieve the same effects as the first embodiment described above.

[0048] <Fourth embodiment> FIG. 9 is an explanatory diagram illustrating the configuration of a foreign body removal device 1C of a fourth embodiment. FIG. 9 is an enlarged longitudinal sectional view of the distal end side of the foreign body removal device 1C when the expandable body 20C is in an expanded state. The foreign body removal device 1C includes an expandable body 20C instead of the expandable body 20 in the configuration of the first embodiment. The shape of the expandable body 20C in the expanded state differs from that of the expandable body 20 described in the first embodiment. Specifically, as shown in FIG. 9, in the expanded state, the expandable body 20C has a tapered shape in which the entire expansion section 21C gradually expands in diameter from the base end side toward the distal end side.

[0049] In this way, the configuration of the expandable body 20C can be modified in various ways, and the shape of the expandable body 20C in the expanded state can be determined arbitrarily. For example, in the expandable body 20C, the expandable section 21C may be a hollow truncated cone shape as shown in Fig. 9, or a shape that combines a truncated cone shape with another shape, or may be an indefinite shape (mesh shape) without a fixed shape. The foreign body removal device 1C of the fourth embodiment as described above can also achieve the same effects as the first embodiment described above.

[0050] <Fifth embodiment> Fig. 10 is an explanatory diagram illustrating the configuration of a foreign body removal device 1D of a fifth embodiment. Fig. 10 is an enlarged longitudinal sectional view of the distal end side of the foreign body removal device 1D when the expandable body 20D is in an expanded state. The foreign body removal device 1D includes an expandable body 20D instead of the expandable body 20 in the configuration of the first embodiment.

[0051] The shape of the expandable body 20D in the expanded state is different from that of the expandable body 20 described in the first embodiment. Specifically, as shown in FIG. 10, in the expanded state, the expandable body 20D has a shape including a non-expanded portion 23, a tapered portion 21b, and a distal portion 21a from the base end side to the distal portion. The non-expanded portion 23 does not expand even when protruding from the outer lumen 11L to the outside, and has the same outer diameter Φ2 as in the contracted state. The tapered portion 21b is a portion that gradually expands in diameter from the base end side to the distal portion. The distal portion 21a is a portion that is located on the side farther from the outer tube 11 and expands into a cylindrical shape having a substantially constant outer diameter.

[0052] The expandable body 20D further has a membrane 24 in a portion on the base end side. The membrane 24 is a membrane-like member formed on the outer or inner surface of the wire constituting the expandable portion 21 and the non-expandable portion 23. The membrane 24 can be formed, for example, from a resin material. Examples of the resin material include fluororesins such as polyamide, polyurethane, and polytetrafluoroethylene (PTFE). In the portion of the expandable body 20D where the membrane 24 is provided, the flow of fluid between the inside and outside of the expandable body 20D is completely blocked. Therefore, in the expandable body 20D, the blood flow BF can be completely blocked in the use state shown in FIG. 6, so that the foreign bodies 92, 93 can be further prevented from being swept away from the lesion to the downstream side of the blood flow BF by the blood flow BF.

[0053] In this way, the configuration of the expansion body 20D can be changed in various ways, and the shape of the expansion body 20D in the expanded state can be determined arbitrarily. For example, the expansion body 20D can be provided with a non-expandable portion 23 that does not expand even when protruding from the outer lumen 11L to the outside. The expansion body 20D can also be provided with a configuration that blocks the flow of fluid, such as a membrane 24. The membrane 24 can be formed between the wires so as to fill the gaps between the wires that constitute the expansion portion 21 and the non-expandable portion 23. The shape of the membrane 24 and the range in which the membrane 24 is provided can be changed arbitrarily. For example, the membrane 24 can be provided over the entire expansion body 20D. The foreign body removal device 1D of the fifth embodiment as described above can also achieve the same effects as those of the first embodiment described above.

[0054] Sixth embodiment Fig. 11 is an explanatory diagram illustrating the configuration of a foreign body removal device 1E of a sixth embodiment. Fig. 11 is an enlarged longitudinal sectional view of the distal end side of the foreign body removal device 1E when the expansion body 20E is in a contracted state. The foreign body removal device 1E includes an expansion body 20E instead of the expansion body 20 in the configuration of the first embodiment. The expansion body 20E includes a support member 22E instead of the support member 22. The support member 22E differs from the support member 22 in that the support member 22E is fixed at an arbitrary position on the distal side of the base end 212 of the expansion section 21. As a result, a part of the expansion section 21 extends to the base end side of the support member 22E.

[0055] In this way, the configuration of the expansion body 20E can be modified in various ways, and the support member 22E may be provided at any location other than the base end of the expansion portion 21. The foreign body removal device 1E of the sixth embodiment as described above can also achieve the same effects as those of the first embodiment described above.

[0056] Seventh embodiment Fig. 12 is an explanatory diagram illustrating the configuration of a foreign body removal device 1F of a seventh embodiment. Fig. 12(A) is an enlarged longitudinal sectional view of the distal end side of the foreign body removal device 1F when the expandable body 20 is in a contracted state. Fig. 12(B) is an enlarged longitudinal sectional view of the distal end side of the foreign body removal device 1F when the expandable body 20 is in an expanded state. The foreign body removal device 1F includes a tube 10F instead of the tube 10 in the configuration of the first embodiment. The tube 10F includes an inner tube 12F instead of the inner tube 12.

[0057] As shown in FIG. 12(A), the tip portion 125 (part 125 on the tip side) of the inner tube 12F is located further distal than the tip 111 of the outer tube 11. In other words, the tip portion 125 of the inner tube 12F protrudes from the outer tube 11. The protruding length of the tip portion 125 (i.e., the length of the inner tube 12F located further distal than the tip 111 of the outer tube 11) may be determined arbitrarily. As shown in FIG. 12(B), when the expandable body 20 is in the expanded state, the tip portion 125 of the inner tube 12F is accommodated inside the expansion portion 21 of the expandable body 20.

[0058] In this way, the configuration of the tube 10F can be modified in various ways, and the tip 125 of the inner tube 12F may be configured to protrude from the outer tube 11. The foreign body removal device 1F of the seventh embodiment as described above can also achieve the same effects as the first embodiment. Furthermore, according to the foreign body removal device 1F, the tip 125 of the inner tube 12F protrudes from the outer tube 11, and the outer tube 11 is not arranged around it, so that the tip side of the tube 10F can be made more flexible than in the configuration of the first embodiment. As a result, the safety of the foreign body removal device 1F can be improved.

[0059] Eighth embodiment Fig. 13 is an explanatory diagram illustrating the configuration of a foreign body removal device 1G of an eighth embodiment. Fig. 13(A) is an enlarged longitudinal sectional view of the distal end side of the foreign body removal device 1G when the expandable body 20 is in a contracted state. Fig. 13(B) is an enlarged longitudinal sectional view of the distal end side of the foreign body removal device 1G when the expandable body 20 is in an expanded state. The foreign body removal device 1G includes a tube 10G instead of the tube 10 in the configuration of the first embodiment. The tube 10G includes an inner tube 12G instead of the inner tube 12.

[0060] As shown in FIG. 13(A), the tip portion 125 of the inner tube 12G is located on the tip side of the tip 111 of the outer tube 11. In other words, the tip portion 125 of the inner tube 12G protrudes from the outer tube 11. In addition, on the outer peripheral surface 12a of the inner tube 12G, on the tip side of the tip 111 of the outer tube 11, a protruding portion 126 is provided in which the outer peripheral surface 12a of the inner tube 12G protrudes outward. In other words, the protruding portion 126 is provided on the outer peripheral surface 12a of the inner tube 12G in a portion corresponding to the tip portion 125 of the inner tube 12G. The protruding portion 126 has a shape in which the central portion is most protruding and the outer diameter gradually decreases toward the end side (the tip side and the base side).

[0061] As shown in FIG. 13(B), the protuberance 126 assists the expansion body 20 in transitioning from a contracted state to an expanded state. Specifically, when the expansion body 20 slides from the first position to the second position, the expansion body 20 naturally expands by moving along the proximal side surface of the protuberance 126 whose outer diameter gradually expands. In addition, when foreign bodies 92, 93 such as thrombi are removed using the foreign body removal device 1G (FIG. 6), the protuberance 126 can prevent the foreign body 93, which has been detached from the lump-like foreign body 92 and captured inside the expansion body 20, from entering between the tip portion 125 of the inner tube 12G and the inside of the expansion portion 21 of the expansion body 20. In addition, the expansion body 20 in the expanded state is easily arranged coaxially with the tube 10G.

[0062] In this way, the configuration of the tube 10G can be modified in various ways, and the distal end 125 of the inner tube 12G may be configured to protrude from the outer tube 11, and a protruding portion 126 may be provided at a portion corresponding to the distal end 125 of the inner tube 12G. The foreign body removal device 1G of the eighth embodiment as described above can also achieve the same effects as the first embodiment described above. In addition, according to the foreign body removal device 1G, the distal end 125 of the inner tube 12G is located on the distal side of the distal end 111 of the outer tube 11, and a protruding portion 126 is provided on the outer peripheral surface 12a of the inner tube 12G on the distal side of the distal end 111 of the outer tube 11. Due to the presence of this protruding portion 126, when the expansion body 20 slides from the first position to the second position, the expansion body 20 can be smoothly guided to the expanded state. In addition, the raised portion 126 can prevent foreign matter such as a captured blood clot from entering between the tip portion 125 of the inner tube 12G (the portion protruding from the outer tube 11) and the inside of the expandable body 20 in the expanded state.

[0063] <Ninth embodiment> Fig. 14 is an explanatory diagram illustrating the configuration of a foreign body removal device 1H of a ninth embodiment. Fig. 14 is an enlarged longitudinal sectional view of the distal end side of the foreign body removal device 1H when the expandable body 20 is in a contracted state. The foreign body removal device 1H includes a tube 10H instead of the tube 10 in the configuration of the first embodiment. The tube 10H includes an inner tube 12H instead of the inner tube 12.

[0064] As shown in FIG. 14, the tip portion 125 of the inner tube 12H is located on the tip side of the tip 111 of the outer tube 11. In other words, the tip portion 125 of the inner tube 12H protrudes from the outer tube 11. In addition, on the outer peripheral surface 12a of the inner tube 12H, a protruding portion 126H is provided on the tip side of the tip 111 of the outer tube 11, where the outer peripheral surface 12a of the inner tube 12H protrudes outward. In other words, the protruding portion 126H is provided on the outer peripheral surface 12a of the inner tube 12H, in a portion corresponding to the tip portion 125 of the inner tube 12H. The protruding portion 126H has a tapered shape on the base end side with the outer diameter decreasing from the tip side to the base end side, and a cylindrical shape on the tip side with a substantially constant outer diameter. Thus, the protruding portion 126H of this embodiment has the same shape as the expansion portion 21 of the expansion body 20 (the base end side is tapered and the tip side is cylindrical).

[0065] In this way, the configuration of the tube 10H can be modified in various ways, and the raised portion 126H can have various shapes. The foreign body removal device 1H of the ninth embodiment as described above can also achieve the same effects as the first and eighth embodiments described above.

[0066] <Modifications of this embodiment> The present invention is not limited to the above-described embodiment, and can be embodied in various forms without departing from the spirit and scope of the invention. For example, the following modifications are also possible.

[0067] [Variation 1] In the above first to ninth embodiments, one example of the configuration of the foreign body removal device 1, 1A to 1H is shown. However, the configuration of the foreign body removal device 1 can be modified in various ways. For example, the reinforcing body 119 of the outer tube 11, 11B may be omitted, and the reinforcing body 129 of the inner tube 12, 12A, 12B, 12F to 12H may be omitted. For example, the reinforcing body 119 and the reinforcing body 129 may be coil bodies in which wires are wound in a spiral shape, instead of a braided body. For example, the outer tube 11 and the inner tube 12 may be double tubes integrally molded to have the above-mentioned outer lumen 11L and inner lumen 12L. For example, the outer peripheral surface of the outer tube 11 and the inner peripheral surface of the inner tube 12 may be coated with a hydrophilic resin or a hydrophobic resin.

[0068] [Variation 2] In the above first to ninth embodiments, one example of the configuration of the expandable body 20, 20C to 20E has been shown. However, the configuration of the expandable body 20 can be modified in various ways. For example, the expandable body 20 does not have to be a self-expanding type. In this case, the expandable body 20 may be a mesh body that does not elastically deform, and may be accommodated in the outer lumen 11L in a folded state like an umbrella. For example, the support member 22 may be coated with a coating that can reduce sliding resistance in the outer lumen 11L.

[0069] For example, when the expansion body 20 is moved to the second position, the base end of the expansion body 20 may be located on the distal side of the distal end 111 of the outer tube 11. In this case, in order to prevent the expansion body 20 from falling off from the foreign body removal device 1, it is desirable that the base end of the expansion body 20 is fixed to the distal end of the outer tube 11 (or the inner tube 12) by a fixing member. The fixing member may be a wire or a membrane.

[0070] FIG. 15 is an explanatory diagram illustrating the configuration of a foreign body removal device 1I of a modified example. FIG. 15(A) shows a contracted state in which the expansion body 20 is contracted. FIG. 15(B) shows a state in which the expansion body 20 transitions from a contracted state to an expanded state. In the above-mentioned first embodiment, the expansion body 20 includes the expansion part 21, which is a self-expanding mesh body, and the support member 22 fixed to the expansion part 21. However, as shown in FIG. 15, the expansion body 20 and the support member 22 do not have to be fixed. In the example of FIG. 15(A), in the contracted state, the expansion body 20 and the support member 22 are separated. In the foreign body removal device 1I, the support member 22 and the expansion body 20 gripped by the seal part 25 are provided between the outer circumferential surface 12a of the inner tube 12 and the inner circumferential surface 11b of the outer tube 11 from the base end side toward the tip end side. The support member 22 is disposed closer to the base end than the expansion body 20. The seal part 25 is provided at the tip of the tube 10, and holds a part of the base end side of the expansion body 20 in a state in which the expansion body 20 and the seal part 25 can slide together in the axial direction. In this configuration, as shown in FIG. 15(B), when the working fluid WF is supplied to the outer lumen 11L, pressure (positive pressure) is applied to the support member 22, and the support member 22, which has moved to the tip side, presses the base end of the expansion body 20, causing the expansion body 20 and the seal part 25 to slide toward the tip side along the axial direction of the foreign body removal device 1. Also, when the working fluid in the outer lumen 11L is sucked, negative pressure is applied to the seal part 25, causing the expansion body 20 and the seal part 25 to slide toward the base end side along the axial direction of the foreign body removal device 1. In this way, the expansion body 20 and the support member 22 do not need to be fixed.

[0071] FIG. 16 is an explanatory diagram illustrating the configuration of a modified foreign body removal device 1J. FIG. 16(A) shows the state in which the expandable body 20 transitions from a contracted state to an expanded state. FIG. 16(B) shows the expandable body 20 in the expanded state. In the above first to ninth embodiments, the foreign body removal device has a base end stopper and a tip stopper (or a reduced diameter portion). As shown in FIG. 16, the foreign body removal device does not need to have a base end stopper and a tip stopper (or a reduced diameter portion). By adjusting the amount of fluid (e.g., liquid) supplied to the outer lumen 11L, the expandable body 20 can be placed at a predetermined position. When the support member 22 is placed between the outer peripheral surface of the inner tube 12J and the inner peripheral surface of the outer tube 11J, it is preferable that the inner diameter of the support member 22 is equal to the outer diameter of the inner tube 12J and the outer diameter of the support member 22 is equal to the inner diameter of the outer tube 11J. This allows the expansion body 20 to be positioned at a predetermined position with greater precision by adjusting the amount of fluid supplied as described above.

[0072] The following configurations (1) to (4) can be employed in the embodiments of the foreign body removal device of the present invention (for example, the first to ninth embodiments). (1) A configuration that does not have a base end stopper and a tip end stopper (or a reduced diameter portion). (2) A configuration having a base end stopper and no tip end stopper (or reduced diameter portion). (3) A configuration having no base end stopper but having a tip end stopper (or a reduced diameter portion). (4) A configuration having a base end stopper and a tip end stopper (or a reduced diameter portion).

[0073] The base end stopper may be a protrusion protruding outward from the outer circumferential surface of the inner tube, or a protrusion protruding inward from the inner circumferential surface of the outer tube. The tip stopper may be a protrusion protruding outward from the outer circumferential surface of the inner tube, or a protrusion protruding inward from the inner circumferential surface of the outer tube. Instead of the tip stopper, a reduced diameter portion formed on the outer tube (e.g., reduced diameter portion 113 shown in FIG. 2) or an expanded diameter portion formed on the inner tube may be used.

[0074] In the foreign body removal devices of the first to ninth embodiments, as shown in Fig. 4, the outer tube 11 and the inner tube 12 are indirectly fixed to each other via a connector 30. However, the outer tube and the inner tube may be directly or indirectly fixed to each other. When the outer tube and the inner tube are indirectly fixed to each other, the connector 30 or a spacer that connects the outer peripheral surface of the inner tube to the inner peripheral surface of the outer tube may be used.

[0075] For example, the foreign body removal device of the first to ninth embodiments may be provided with a fluid outlet (e.g., first opening 311 in FIG. 4) that leads to the inner cavity of the inner tube, and a fluid supply and exhaust port (e.g., second opening 312 in FIG. 4) that leads to a gap between the inner tube and the outer tube and on the base side of the expandable body.

[0076] [Variation 3] The configurations of the foreign body removal devices 1, 1A-1H of the first to ninth embodiments and the configurations of the foreign body removal devices 1, 1A-1H of the above-mentioned modified examples 1 and 2 may be appropriately combined. For example, the configuration of the portion that restricts the sliding movement of the expansion body 20 described in the second and third embodiments, the configurations of the expansion bodies 20C, 20D, and 20E described in the fourth, fifth, and sixth embodiments, and the configurations of the tubes 10F, 10G, and 10H described in the seventh, eighth, and ninth embodiments may be appropriately combined.

[0077] Although the present aspect has been described above based on the embodiment and modified examples, the above-mentioned embodiment of the aspect is intended to facilitate understanding of the present aspect and does not limit the present aspect. The present aspect may be modified or improved without departing from the spirit and scope of the claims, and equivalents are included in the present aspect. Furthermore, if a technical feature is not described as essential in this specification, it may be deleted as appropriate. [Explanation of symbols]

[0078] 1, 1A~1J…Foreign object removal device 10, 10A, 10B, 10F~10H...Tube 11, 11B, 11J...Outer tube 11L…Outer lumen 11b…Inner peripheral surface 12, 12A, 12B, 12F~12H, 12J...Inner tube 12L…Inner lumen 12a...Outer surface 20,20C~20E…Extension body 21, 21C…Extension 22, 22E…Support member 23...Non-expandable section 24...Membrane 25…Seal section 30…Connector 31...First extension part 31L…Suction lumen 32…Second extension part 32L…lumen 33…Latching part 34…Step 113...Reduced diameter part 114...Base end stopper 119…Reinforcement body 123, 123A…Base end stopper 124...Tip stopper 125...Tip 126,126H…Protuberance 129…Reinforcement body 201...Tip opening 311…First opening 312…First fitting portion 321...Second opening 322…Second fitting part

Claims

1. A foreign object removal device, an inner tube, an outer tube disposed surrounding the periphery of the inner tube, a cylindrical expansion body disposed between the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube, comprising: the expansion body can change the relative positions with respect to the inner tube and the outer tube by sliding in the axial direction of the foreign object removal device, the foreign object removal device.

2. The foreign object removal device according to Claim 1, wherein the expansion body both the tip and the base end of the expansion body are in a first position located on the base end side of the tip of the outer tube, the tip of the expansion body is located on the tip side of the tip of the outer tube, and the base end of the expansion body is located on the base end side of the tip of the outer tube, a second position, and slides between them, the foreign object removal device.

3. The foreign object removal device according to Claim 1 or Claim 2, wherein an annular support member is provided between the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube, on the base end side of the expansion body, the foreign object removal device.

4. The foreign object removal device according to Claim 1 or Claim 2, the tip of the inner tube is located on the tip side of the tip of the outer tube, a raised portion where the outer peripheral surface of the inner tube bulges outward is provided on the tip side of the tip of the outer tube on the outer peripheral surface of the inner tube, the foreign object removal device.

Images