Catheter

Abstract

To suppress narrowing of a passage for an instrument and fluid in a catheter.SOLUTION: A catheter 1 includes: a shaft 2 having a plurality of lumens 7; a handle 6 which has a plurality of ports 17 corresponding to the plurality of lumens 7, and is connected to a base end side of the shaft 2; and a metal tube 41 provided for at least one lumen 7, where a tip side of the metal tube 41 is inserted into an opening of the lumen 7 on a base end face of the shaft 2, and a base end side is directly or indirectly connected to the port 17 corresponding to the lumen 7.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to catheters. [Background technology]

[0002] Conventionally, multi-lumen catheters having multiple lumens have been known. For example, the catheter described in Patent Document 1 includes a balloon lumen through which air passes to inflate a balloon provided on the catheter shaft, a contrast medium lumen through which a contrast medium passes, and a guidewire lumen through which a guidewire passes. Furthermore, a branch tube is inserted into each lumen. An air injection syringe is connected to the balloon lumen, a contrast medium injection syringe is connected to the contrast medium lumen, and a guidewire is inserted into the guidewire lumen via each branch tube. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-229129 Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional multi-lumen catheters, resin branch tubes are inserted to connect or insert instruments such as fluid injection syringes and guidewires into each lumen. In such a structure, the inner diameter of the branch tube is typically smaller than the inner diameter of the lumen. Therefore, inserting a branch tube into a lumen narrows the passageway for instruments and fluids, potentially limiting the instruments that can be inserted and the flow rate of fluids.

[0005] The present disclosure has been made in light of these circumstances, and its purpose is to provide a technique for suppressing narrowing of passages for instruments, fluids, etc. in a catheter. [Means for solving the problem]

[0006] One aspect of the present disclosure is a catheter comprising: a shaft having multiple lumens; a handle having multiple ports corresponding to the multiple lumens and connected to the proximal end of the shaft; and a metal tube provided for at least one of the lumens, the distal end of which is inserted into an opening of the lumen at the proximal end surface of the shaft, and the proximal end of which is connected directly or indirectly to the port corresponding to the lumen.

[0007] Any combination of the above components, and conversion of the expression of the present disclosure into a method, device, system, etc., are also valid aspects of the present disclosure. [Effects of the Invention]

[0008] According to the present disclosure, narrowing of the passage for instruments, fluids, etc. in the catheter can be suppressed. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a side view of a catheter according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view of the shaft along the radial direction. [Figure 3] FIG. 2 is a diagram showing the internal structure of the handle. [Figure 4] FIG. 1 is an enlarged view of the internal structure in the tip region of the handle. [Figure 5] FIG. 10 is a schematic diagram showing how each lumen is connected to each metal tube. [Figure 6] FIG. 10 is a schematic diagram showing a state in which each lumen and each metal tube are connected in a catheter according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present disclosure will be described below with reference to preferred embodiments and drawings. The embodiments are illustrative and do not limit the present disclosure, and all features and combinations thereof described in the embodiments are not necessarily essential to the present disclosure. The same or equivalent components, parts, and processes shown in each drawing are designated by the same reference numerals, and redundant descriptions will be omitted where appropriate. The scale and shape of each part shown in each drawing are set for convenience to facilitate explanation and should not be interpreted as limiting unless otherwise specified. Furthermore, when terms such as "first" and "second" are used in this specification or claims, unless otherwise specified, these terms do not indicate any order or importance, but are intended to distinguish one configuration from another. Furthermore, some components that are not important for explaining the embodiments are omitted from each drawing.

[0011] FIG. 1 is a side view of a catheter 1 according to an embodiment. The catheter 1 according to this embodiment includes, for example, a shaft 2, a balloon 4, and a handle 6. The shaft 2 is a long, flexible tubular member. The shaft 2 is made of a known flexible material, including resins such as polyolefin, polytetrafluoroethylene, polyether block amide, polyamide, polyurethane, and silicone. The length of the shaft 2 is, for example, 600 mm to 3000 mm. The balloon 4 is disposed on the circumferential surface of the shaft 2 at one end thereof. The handle 6 is connected to the other end of the shaft 2.

[0012] Hereinafter, the side of the catheter 1 on which the balloon 4 is disposed will be referred to as the "distal side," and the side on which the handle 6 is disposed will be referred to as the "proximal side." For each member constituting the catheter 1, the side closer to the distal end of the catheter 1 will be referred to as the "distal side," and the side closer to the proximal end of the catheter 1 will be referred to as the "proximal side." The direction in which the axis of the shaft 2 extends, in other words, the longitudinal direction of the shaft 2, will be referred to as the "axial direction." In addition, in a cross section of the shaft 2 perpendicular to the axial direction, the direction parallel to the radius of the shaft 2 will be referred to as the "radial direction."

[0013] At least the tip end of the shaft 2 is inserted into the body. This causes the balloon 4 to be delivered into the body. The balloon 4 has a known structure and will not be described here. The handle 6, also called a hub, is located outside the body and is grasped or operated by the practitioner.

[0014] FIG. 2 is a cross-sectional view of the shaft 2 taken along the radial direction. FIG. 2 illustrates the cross-section of the shaft 2 as viewed from the distal end. The shaft 2 is a multi-lumen shaft having multiple lumens 7. The number of lumens 7 that the shaft 2 has may be two or more. The shaft 2 of this embodiment has, as an example, a first lumen 8, a second lumen 10, a third lumen 12, and a fourth lumen 14. Hereinafter, when there is no need to distinguish between the first lumen 8 to the fourth lumen 14, they will be collectively referred to as lumens 7.

[0015] The first lumen 8 extends from the base end surface to the tip end surface of the shaft 2, and an endoscope is passed through it. The second lumen 10 extends from the base end surface to the tip end surface of the shaft 2, and is used to pass treatment tools such as forceps, cannula, guide wire, and stent, medicinal liquids to be supplied to the affected area, blood to be sucked from the affected area, tissue fluid, etc.

[0016] The third lumen 12 extends from the proximal end surface of the shaft 2 into the balloon 4, and an opening on the distal end side is connected to the inside of the balloon 4. A fluid, for example, a gas such as air, is passed through the third lumen 12 to inflate the balloon 4. The fluid flowing through the third lumen 12 is released into the balloon 4 from the opening on the distal end side of the third lumen 12.

[0017] The fourth lumen 14 extends from the proximal end surface to the distal end surface of the shaft 2. The shaft 2 also has a through-hole (not shown) on its side near the balloon 4 that connects the inside of the fourth lumen 14 to the outside of the shaft 2. A liquid such as saline or a contrast agent is passed through the fourth lumen 14. The liquid flowing through the fourth lumen 14 is discharged to the outside of the shaft 2 from the through-hole. The opening on the distal end side of the fourth lumen 14 is sealed with an adhesive or the like.

[0018] As an example, the outer diameter of the shaft 2 is 2.7 mm. The diameter of the first lumen 8 is 1.1 mm. The diameter of the second lumen 10 is 1.2 mm. The diameters of the third lumen 12 and the fourth lumen 14 are each 0.7 mm. The arrangement, diameter, and inserted material of each lumen 7 can be set as appropriate. There are also no particular limitations on the manner in which the third lumen 12 and the balloon 4 are connected, and the manner in which the fourth lumen 14 is connected to the outside of the shaft 2 can be set as appropriate.

[0019] When electrodes, thermocouples, etc. are provided on the surface of the balloon 4 or the tip of the shaft 2, a conducting wire may be passed through one of the lumens 7. Also, the catheter 1 of this embodiment is used as a balloon catheter for stone removal, for example. The catheter 1 can also be used for procedures other than stone removal. Depending on the procedure in which the catheter 1 is used, the balloon 4 may be omitted.

[0020] 3 is a diagram showing the internal structure of the handle 6. The handle 6 has a main body 16 and a plurality of ports 17 corresponding to the plurality of lumens 7. The catheter 1 of this embodiment also has a plurality of access tubes 29 extending from each port 17.

[0021] The main body 16 is made of a known resin such as polycarbonate (PC), polysulfone (PSU), polyetherimide (PEI), acrylonitrile-butadiene-styrene copolymer (ABS), etc., and can be formed by known injection molding, etc. The main body 16 is approximately cylindrical and long in the axial direction, and is held by the operator.

[0022] The multiple ports 17 are each connected to the main body 16. The handle 6 of this embodiment has a first port 18, a second port 20, a third port 22, a fourth port 24, a fifth port 26, and a sixth port 28. Hereinafter, when there is no need to distinguish between the first port 18 to the sixth port 28, they will be collectively referred to as ports 17. Examples of materials constituting each port 17 include the same materials as those of the main body 16.

[0023] The catheter 1 of this embodiment also includes a first access tube 30, a second access tube 32, a third access tube 34, a fourth access tube 36, and a fifth access tube 38. Hereinafter, when there is no need to distinguish between the first access tube 30 to the fifth access tube 38, they will be collectively referred to as access tubes 29. Examples of materials constituting each access tube 29 include the same materials as those of the shaft 2.

[0024] The first port 18 corresponds to the first lumen 8, and an endoscope is inserted through the first port 18. The first port 18 is directly fixed to the main body 16, and is connected to the first lumen 8 via a first access tube 30 that extends within the main body 16.

[0025] The second port 20 corresponds to the second lumen 10, through which a treatment tool is inserted. The third port 22 corresponds to the second lumen 10, through which a medicinal solution is injected. Furthermore, blood, tissue fluid, etc. aspirated from the affected area are discharged. The fourth port 24 corresponds to the second lumen 10, through which blood, tissue fluid, etc. aspirated from the affected area are discharged. As an example, the handle 6 has a collecting pipe 40. The second port 20 and the third port 22 are each connected to the collecting pipe 40. For example, the second port 20, the third port 22, and the collecting pipe 40 are integrally molded parts, and this integrally molded part is directly fixed to the main body 16. The fourth port 24 is connected to the collecting pipe 40 via a third access tube 34 extending from within the main body 16 to the outside. The collecting pipe 40 is connected to the second lumen 10 via a second access tube 32 extending within the main body 16.

[0026] The fifth port 26 corresponds to the third lumen 12, and is used to inject a fluid for expanding the balloon 4 and to discharge the fluid from the balloon 4. The fifth port 26 is directly fixed to the main body 16, and is connected to the third lumen 12 via a fourth access tube 36 that extends within the main body 16.

[0027] The sixth port 28 corresponds to the fourth lumen 14, and a liquid such as saline or a contrast agent is injected into the sixth port 28. The sixth port 28 is connected to the fourth lumen 14 via a fifth access tube 38 that extends from inside the main body 16 to the outside.

[0028] Each lumen 7 and each access tube 29 are connected to one another via a metal tube 41. FIG. 4 is an enlarged view of the internal structure in the distal end region of the handle 6. FIG. 5 is a schematic diagram showing how each lumen 7 and each metal tube 41 are connected. The catheter 1 of this embodiment includes a first metal tube 42, a second metal tube 44, a third metal tube 46, and a fourth metal tube 48. Hereinafter, when there is no need to distinguish between the first metal tube 42 to the fourth metal tube 48, they will be collectively referred to as the metal tube 41. Each metal tube 41 is made of a known metal such as stainless steel (SUS) or nickel-titanium alloy (NiTi).

[0029] The distal end side of the first metal tube 42 is inserted into the opening of the first lumen 8 in the proximal end surface 2 a of the shaft 2. Furthermore, the proximal end side of the first metal tube 42 is inserted into the opening of the first access tube 30. Therefore, the proximal end side of the first metal tube 42 is indirectly connected to the first port 18 corresponding to the first lumen 8 via the first access tube 30.

[0030] The distal end side of the second metal tube 44 is inserted into the opening of the second lumen 10 in the proximal end surface 2a of the shaft 2. The proximal end side of the second metal tube 44 is inserted into the opening of the second access tube 32. Therefore, the proximal end side of the second metal tube 44 is indirectly connected to the second port 20 and the third port 22 corresponding to the second lumen 10 via the second access tube 32. The proximal end side of the second metal tube 44 is indirectly connected to the fourth port 24 corresponding to the second lumen 10 via the second access tube 32 and the third access tube 34.

[0031] The distal end side of the third metal tube 46 is inserted into the opening of the third lumen 12 in the proximal end surface 2 a of the shaft 2. Furthermore, the proximal end side of the third metal tube 46 is inserted into the opening of the fourth access tube 36. Therefore, the proximal end side of the third metal tube 46 is indirectly connected to the fifth port 26 corresponding to the third lumen 12 via the fourth access tube 36.

[0032] The distal end side of the fourth metal tube 48 is inserted into the opening of the fourth lumen 14 in the proximal end surface 2 a of the shaft 2. Furthermore, the proximal end side of the fourth metal tube 48 is inserted into the opening of the fifth access tube 38. Therefore, the proximal end side of the fourth metal tube 48 is indirectly connected to the sixth port 28 corresponding to the fourth lumen 14 via the fifth access tube 38.

[0033] Preferably, the outer diameter of each metal tube 41 is larger than the inner diameter of each lumen 7 before the metal tube 41 is inserted. That is, the outer diameter of the first metal tube 42 is larger than the inner diameter of the first lumen 8 before the first metal tube 42 is inserted. Furthermore, the outer diameter of the second metal tube 44 is larger than the inner diameter of the second lumen 10 before the second metal tube 44 is inserted. Furthermore, the outer diameter of the third metal tube 46 is larger than the inner diameter of the third lumen 12 before the third metal tube 46 is inserted. Furthermore, the outer diameter of the fourth metal tube 48 is larger than the inner diameter of the fourth lumen 14 before the fourth metal tube 48 is inserted.

[0034] In the present disclosure, the inner diameter of the lumen 7 before the metal tube 41 is inserted can be assumed to be the inner diameter of a region of the lumen 7 where the metal tube 41 does not extend after the metal tube 41 has been inserted. Also, as an example, the outer diameter of the metal tube 41 and the inner diameter of the lumen 7 are average values ​​of diameters at multiple points in the axial direction. Also, the outer diameter of the metal tube 41 is measured at the portion inserted into the lumen 7. The inner diameter of the lumen 7 is measured at a region that is in contact with the tip of the metal tube 41 and has the same length in the axial direction as the portion of the metal tube 41 inserted into the lumen 7.

[0035] As described above, the catheter 1 of this embodiment includes the shaft 2 having multiple lumens 7, the handle 6 having multiple ports 17 corresponding to the multiple lumens 7, and the metal tube 41 whose distal end is inserted into the lumen 7 and whose proximal end is connected to the port 17. The metal tube 41 has higher rigidity than a branch tube made of resin, in other words, a resin tube. Therefore, the wall thickness can be made thinner than that of a resin tube. Therefore, by inserting the metal tube 41 into the lumen 7 and connecting the lumen 7 to the port 17 via the metal tube 41, it is possible to prevent the passage of instruments, fluids, etc. from being narrowed.

[0036] Furthermore, when inserting a tube, whether made of metal or resin, into the lumen 7, the passage from the port 17 to the tip of the lumen 7 tends to have the smallest cross-sectional area in the tube. For this reason, the dimensions of the lumen 7 are set based on the inner diameter of the tube. That is, the inner diameter of the tube is set so that a desired fluid flow rate can be achieved in the tube or so that a desired instrument can be inserted. The dimensions of the lumen 7 are then set so that the set inner diameter of the tube can be achieved. If a thick-walled resin tube is used in such a configuration, the lumen 7 may become unnecessarily thick, which may lead to an increase in the diameter of the shaft 2 or a decrease in the number of lumens that can be formed in the shaft 2. In contrast, in the present embodiment, a thin-walled metal tube 41 is used, which prevents the lumen 7 from becoming unnecessarily thick. This makes it easier to reduce the diameter of the shaft 2 or increase the number of lumens.

[0037] Furthermore, the metal tube 41 has higher rigidity than a resin tube, and is therefore easier to insert into the lumen 7. Furthermore, the shape of the passage for instruments, fluids, etc. can be more easily maintained when the catheter 1 is in use. Furthermore, when the metal tube 41 is used, the metal tube 41 and the shaft 2 can be firmly connected by thermally shrinking the shaft 2 after inserting the metal tube 41 into the lumen 7. Furthermore, the connection between the metal tube 41 and the lumen 7 can be airtightly sealed. In the case of a resin tube, there is a risk that the resin tube will also be deformed when the shaft 2 is thermally shrunk. Therefore, by using the metal tube 41, it is easier to achieve the above-mentioned strong connection and sealing compared to when a resin tube is used.

[0038] Furthermore, by making the outer diameter of each metal tube 41 larger than the inner diameter of each lumen 7 before the metal tube 41 is inserted, the metal tube 41 and the shaft 2 can be firmly connected and the connection between the metal tube 41 and the lumen 7 can be airtightly sealed. Due to its high rigidity, the metal tube 41 can be easily press-fitted into the lumen 7, which is thinner than the metal tube 41. On the other hand, if a resin tube is used, there is a risk that the resin tube will be deformed or damaged when being press-fitted into the lumen 7. Therefore, by using the metal tube 41, it is easier to achieve the above-mentioned strong connection and sealing compared to using a resin tube.

[0039] In this embodiment, metal tubes 41 are provided for all lumens 7. This makes it possible to prevent narrowing in all passages. However, this configuration is not limiting, and it is sufficient that a metal tube 41 is provided for at least one lumen 7. This makes it possible to prevent narrowing in at least one passage. When metal tubes 41 are provided for only some of the lumens 7, it is preferable that the metal tubes 41 are provided for at least the lumens 7 through which fluid passes. In this embodiment, the lumens 7 through which fluid passes are the second lumen 10 to the fourth lumen 14. By inserting metal tubes 41 into the lumens 7 through which fluid passes, it is possible to more easily prevent fluid leakage from the connection between the lumens 7 and the metal tubes 41 than when a resin tube is inserted.

[0040] The catheter 1 of this embodiment also includes an access tube 29 extending from the port 17. The proximal end of the metal tube 41 is inserted into the access tube 29. This makes it easier to distribute the placement of the ports 17. As a result, it is possible to ease the concentration of external devices connected to the handle 6, and reduce the care that must be taken to avoid interference between the external devices and to distinguish between the external devices. Furthermore, it is possible to increase the number of ports 17 that can be installed in the handle 6. Therefore, it is possible to improve the operability of procedures using the catheter 1.

[0041] Note that the metal tubes 41 may be directly connected to the ports 17. For example, some of the metal tubes 41 may be directly connected to the ports 17, and the remaining metal tubes 41 may be indirectly connected to the ports 17 via the access tubes 29. Also, for example, some combinations of lumens 7 and ports 17 may be connected only by the metal tubes 41, and the remaining combinations of lumens 7 and ports 17 may be connected only by the access tubes 29.

[0042] The embodiments of the present disclosure have been described in detail above. The above-described embodiments merely illustrate specific examples of implementing the present disclosure. The content of the embodiments does not limit the technical scope of the present disclosure, and many design modifications, such as changing, adding, or deleting components, are possible within the scope of the concept of the present disclosure defined in the claims. A new embodiment with design modifications will combine the effects of the combined embodiments and modifications. In the above-described embodiments, the content that allows such design modifications is emphasized by using notations such as "in this embodiment" or "in this embodiment," but design modifications are also permitted even in content without such notation. Any combination of the components included in each embodiment is also valid as an aspect of the present disclosure. Hatching on cross sections in the drawings does not limit the material of the hatched object.

[0043] (Variation) 6 is a schematic diagram showing how each lumens 7 and each metal tube 41 are connected in a catheter 1 according to a modified example. In the catheter 1 according to the embodiment, the tips of the metal tubes 41 are aligned in the axial direction. On the other hand, in the catheter 1 according to the modified example, some of the metal tubes 41 are inserted deeper into the lumen 7 than the other metal tubes 41. Therefore, the tips of these metal tubes 41 are located closer to the tip of the shaft 2 than the tips of the other metal tubes 41. As an example, the insertion distance of the third metal tube 46 into the third lumen 12 is greater than the insertion distance of the other metal tubes 41 into the lumens 7. Therefore, the tip of the third metal tube 46 is located closer to the tip of the shaft 2 than the tips of the other metal tubes 41.

[0044] When inserting the metal tubes 41 into each lumen 7, stress may concentrate on the wall of the shaft 2 sandwiched between adjacent metal tubes 41, i.e., on the partition wall separating the two adjacent lumens 7, potentially damaging that portion. Furthermore, if the tips of the metal tubes 41 are aligned, stress may concentrate on the shaft 2 near the tip of each metal tube 41, potentially damaging that portion. It is desirable to avoid such damage to the shaft 2. In particular, it is desirable to avoid damage to the partition wall separating the third lumen 12 in the shaft 2 and the portion near the tip of the third lumen 12 as much as possible. This is because a fluid for inflating the balloon 4 flows through the third lumen 12, and the flow rate of the fluid through the third lumen 12 must be precisely adjusted in order to precisely adjust the size of the balloon 4.

[0045] In contrast, in this modification, the tip of the third metal tube 46 is located closer to the tip of the shaft 2 than the tips of the other metal tubes 41. This makes it possible to reduce stress on the partition wall that defines the third lumen 12 in the shaft 2 and on the portion near the tip of the third lumen 12. This makes it possible to prevent damage to these portions. Note that the tip of a metal tube 41 inserted into a lumen 7 other than the third lumen 12 may be located closer to the tip of the shaft 2 than the tips of the other metal tubes 41. This makes it possible to reduce stress on the partition wall that defines the other metal tube 41 and on the portion near the tip of the other metal tube 41.

[0046] The embodiments may be specified by the following items. [1st item] a shaft (2) having a plurality of lumens (7, 8, 10, 12, 14); a handle (6) having a plurality of ports (17, 18, 20, 22, 24, 26, 28) corresponding to a plurality of lumens (7, 8, 10, 12, 14) and connected to a proximal end side of the shaft (2); and metal tubes (41, 42, 44, 46, 48) provided for at least one lumen (7, 8, 10, 12, 14), the distal end of which is inserted into an opening of the lumen (7, 8, 10, 12, 14) in the proximal end surface (2a) of the shaft (2), and the proximal end of which is connected directly or indirectly to ports (17, 18, 20, 22, 24, 26, 28) corresponding to the lumen (7, 8, 10, 12, 14). Catheter (1). [Second item] access tubes (29, 30, 32, 34, 36, 38) extending from the ports (17, 18, 20, 22, 24, 26, 28); The proximal ends of the metal tubes (41, 42, 44, 46, 48) are inserted into the access tubes (29, 30, 32, 36, 38). A catheter (1) according to claim 1. [3rd item] The outer diameter of the metal tubes (41, 42, 44, 46, 48) is larger than the inner diameter of the lumens (7, 8, 10, 12, 14) before the metal tubes (41, 42, 44, 46, 48) are inserted. A catheter (1) according to the first or second item. [4th item] Metal tubes (41, 44, 46, 48) are provided for at least the fluid-carrying lumens (7, 10, 12, 14). A catheter (1) according to any one of the first to third items. [Item 5] Metal tubes (41, 42, 44, 46, 48) are provided for all lumens (7, 8, 10, 12, 14). A catheter (1) according to any one of the first to fourth items. [Explanation of symbols]

[0047] 1 catheter, 2 shaft, 2a proximal end face, 6 handle, 7 lumen, 17 port, 29 access tube, 41 metal tube.

Claims

1. a shaft having multiple lumens; a handle having a plurality of ports corresponding to the plurality of lumens and connected to a proximal end side of the shaft; a metal tube provided for at least one of the lumens, the metal tube having a distal end inserted into an opening of the lumen at the proximal end surface of the shaft and a proximal end connected directly or indirectly to the port corresponding to the lumen; catheter.

2. an access tube extending from the port; The proximal end of the metal tube is inserted into the access tube. The catheter of claim 1.

3. The outer diameter of the metal tube is larger than the inner diameter of the lumen before the metal tube is inserted. The catheter according to claim 1 or 2.

4. The metal tube is provided for the lumen through which at least a fluid passes. The catheter according to claim 1 or 2.

5. The metal tube is provided for all of the lumens. The catheter according to claim 1 or 2.

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