Catheter shaft and catheter
By setting an eccentric working channel and reinforcement layer structure in the catheter shaft, the wrinkle problem during the catheter shaft insertion and removal process is solved, and the ease of insertion and removal of the instrument is improved.
Patent Information
- Application Number
- CN202410214196.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-06-30
- Filing Date
- 2024-02-27
- Publication Date
- 2024-12-31
AI Technical Summary
The existing catheter shaft is prone to wrinkles during the insertion and removal process, resulting in a decrease in operability of the disposal device, especially when the catheter shaft in thin-walled parts is bent, it is difficult to insert and unplug.
A catheter shaft is designed, with the working passage eccentric to the axis of the catheter shaft, and in the portion of the catheter shaft, a sandwich structure between the inner layer and the outer layer is ensured by providing a second reinforcement layer and a first reinforcement layer. , avoid wrinkles in thin-walled areas and improve the ease of insertion and removal.
Through this structural design, the wrinkles of thin walls around the working channel are suppressed, the ease of insertion and removal of the disposal instruments and the workingability of using the catheter are improved, and the stability and operational convenience of the catheter are ensured.
Smart Images
Figure CN119214751A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to a catheter shaft and a catheter. Background Art
[0002] Patent Document 1 discloses a catheter shaft including a camera channel through which a camera is inserted, a forceps channel through which a forceps is inserted, and a plurality of wire lumens.
[0003] Prior art literature
[0004] Patent Literature
[0005] Patent Document 1: International Publication No. 2022 / 172321 Summary of the invention
[0006] Problems to be solved by the invention
[0007] The inventors have repeatedly conducted in-depth research on a catheter shaft having a working channel for passing a treatment instrument such as forceps and multiple lumens for passing sensors including cameras, pull wires, etc. As a result, they have come up with a shaft structure that can improve the ease of inserting and removing the treatment instrument from the working channel.
[0008] The present disclosure has been made in view of such a situation, and an object of the present disclosure is to provide a technology for improving the ease of insertion and removal of a treatment instrument with respect to a working channel.
[0009] Technical Solution
[0010] A certain scheme of the present disclosure is a catheter shaft. The catheter shaft comprises an outer layer and an inner layer covered by the outer layer, and the inner layer is provided with at least one working channel for a disposal instrument to pass through, at least four wire puller cavities for wire pullers to pass through, and at least one sensor cavity for at least a portion of a sensor to pass through. The working channel is eccentric with respect to the axis of the catheter shaft. In at least a portion of the catheter shaft, in a cross-sectional observation orthogonal to the axis of the catheter shaft, the shortest distance from the outer peripheral surface of the portion of the working channel closest to the outer layer is longer than the shortest distance from the outer peripheral surface of the portion of each wire puller cavity closest to the outer peripheral surface of the outer layer to the outer peripheral surface of the outer layer, and is longer than the shortest distance from the outer peripheral surface of the portion of the sensor cavity closest to the outer peripheral surface of the outer layer to the outer peripheral surface of the outer layer.
[0011] Another scheme of the present disclosure is a catheter shaft. The catheter shaft has an outer layer and an inner layer covered by the outer layer, and the inner layer is provided with at least one working channel tube forming a working channel for a disposal instrument to pass through, at least four wire puller lumens forming wire puller lumens for a wire puller to pass through, and at least one sensor lumen forming a sensor lumen for at least a portion of a sensor to pass through. The working channel tube is eccentric relative to the axis of the catheter shaft. In at least a portion of the catheter shaft, under a cross-sectional observation orthogonal to the axis of the catheter shaft, each wire puller lumen and the sensor lumen are connected to the outer layer, and the working channel tube does not contact the outer layer.
[0012] Another aspect of the present disclosure is a catheter including: a catheter shaft according to any one of the above aspects; and a handle located on the proximal end side of the catheter shaft.
[0013] Optional combinations of the above-described constituent elements and solutions in which the expressions of the present disclosure are converted into methods, apparatuses, systems, and the like are also effective as aspects of the present disclosure.
[0014] Effects of the Invention
[0015] According to the present disclosure, the ease of inserting and removing the treatment instrument with respect to the working channel can be improved. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 This is a top view of the catheter according to Embodiment 1.
[0017] Figure 2 It is a three-dimensional view of the tip of the catheter.
[0018] Figure 3 It is a three-dimensional view of the tip of the catheter.
[0019] Figure 4 This is a cross-sectional view of the catheter shaft according to the first embodiment.
[0020] Figure 5 (A) is along Figure 4 Cross-sectional view along line AA. Figure 5 (B) is along Figure 4 Cross-sectional view of line BB.
[0021] Figure 6 It is a diagram for explaining the arrangement of the wire pulling cavity.
[0022] Figure 7 This is a cross-sectional view of the catheter shaft according to the second embodiment. DETAILED DESCRIPTION
[0023] Hereinafter, the present disclosure will be described based on a preferred embodiment and with reference to the accompanying drawings. The embodiments do not limit the present disclosure but are examples. All the features described in the embodiments and their combinations are not necessarily the essential contents of the present disclosure. The same or equivalent components, members, and processes shown in the drawings are marked with the same figure marks, and repeated descriptions are appropriately omitted. In addition, for the convenience of explanation, the scales and shapes of the various parts shown in the figures are set in a convenient manner, and are not interpreted in a restrictive manner unless otherwise mentioned. In addition, when terms such as "first" and "second" are used in this specification or technical solution, unless otherwise mentioned, the terms are used to distinguish a certain composition from other compositions, and do not indicate any order or importance. In addition, in each of the drawings, on the basis of the description of the embodiment, a part of the unimportant components will be omitted.
[0024] (Implementation Method 1)
[0025] Figure 1 1 is a top view of a catheter 1 according to Embodiment 1. The catheter 1 can be used to treat a living organ such as a bile duct or a pancreatic duct. The catheter 1 includes a catheter shaft 2 , a handle 4 , and a distal tip 6 .
[0026] The catheter shaft 2 is a long tubular member. As the raw material of the catheter shaft 2, there are flexible materials such as resin. The length of the catheter shaft 2 is, for example, 200 mm to 4800 mm. The handle 4 is provided at the base end (proximal end) of the catheter shaft 2. The top tip 6 is provided at the top end (distal end) of the catheter shaft 2. Hereinafter, the top tip 6 side of the catheter 1 and each component constituting the catheter 1 will be appropriately referred to as the "top end side", and the handle 4 side will be referred to as the "base end side". In addition, the direction in which the axis of the catheter shaft 2 extends will be referred to as the "axial direction", the direction orthogonal to the axis will be referred to as the "radial direction", and the direction around the axis will be referred to as the "circumferential direction".
[0027] The catheter shaft 2 has a working channel 42, four puller lumens 44, a sensor lumen 46, and two fluid lumens 48 (see Figure 4 The pull wire 56 passes through each pull wire cavity 44.
[0028] The catheter shaft 2 has a tip region 2A that can be intentionally bent by pulling the pull wire 56. The tip region 2A can be formed in a desired range by making the hardness (for example, Shore D hardness) of the resin constituting the catheter shaft 2 different between the tip region 2A and the region closer to the proximal end than the tip region 2A. The tip region 2A is, for example, a region extending from the tip of the catheter shaft 2 to 50 mm.
[0029] The handle 4 is disposed outside the body and is operated by a therapist such as a doctor. As an example, the handle 4 includes a grip 8, two operation knobs 10 and 12, a working channel port 14, a sensor port 16, and a fluid port (not shown).
[0030] The handle 8 is grasped by the therapist. The base ends of two pull wires 56 are mounted on the operating knob 10. The base ends of the remaining two pull wires 56 are mounted on the operating knob 12. When the operating knob 10 is rotated in one direction, the pull wire 56 on one side connected to the operating knob 10 is stretched toward the base end. When the operating knob 10 is rotated in the other direction, the pull wire 56 on the other side connected to the operating knob 10 is stretched toward the base end. When the operating knob 12 is rotated in one direction, the pull wire 56 on one side connected to the operating knob 12 is stretched toward the base end. When the operating knob 12 is rotated in the other direction, the pull wire 56 on the other side connected to the operating knob 12 is stretched toward the base end. By stretching the four pull wires 56, the top region 2A can be bent in multiple directions. The technology of using the pull wires 56 to bend the top region 2A is well known, so a more detailed description is omitted.
[0031] The working channel port 14 is in fluid communication with the working channel 42. The therapist can insert and remove treatment instruments relative to the working channel 42 via the working channel port 14. The sensor port 16 is in fluid communication with the sensor cavity 46. The sensor cable 18 passes through the sensor cavity 46 via the sensor port 16. As an example, a connector 20 is provided on the cable 18, and the cable 18 is fixed to the handle 4 by installing the connector 20 on the sensor port 16. The fluid port is in fluid communication with the fluid cavity 48.
[0032] The distal tip 6 is inserted into the distal end of the catheter shaft 2. The distal tip 6 is delivered to a treatment site in the body by inserting the distal end side of the catheter shaft 2 into the body. Figure 2 and Figure 3 is a three-dimensional diagram of the top end of the catheter 1. It should be noted that Figure 2 and Figure 3 , the state in which the portion of the outer layer 38 overlapping with the top tip 6 is cut away is shown. Figure 3 In the figure, the pull wire 56 is omitted.
[0033] The distal tip 6 is a substantially cylindrical member extending in the axial direction of the catheter shaft 2. The material of the distal tip 6 is, for example, the same as that of the catheter shaft 2. The distal tip 6 has a first through hole 22 extending from the distal side to the proximal side. The proximal side of the first through hole 22 communicates with the working channel 42.
[0034] The tip 6 has a sensor groove 24 at the tip. The sensor cavity 46 is connected to the bottom of the sensor groove 24. The catheter 1 of this embodiment has a camera module 26 as a sensor. The camera module 26 is composed of a camera 28 equipped with a CMOS (Complementary Metal-Oxide-Semiconductor) image sensor and a cable 18 extending from the camera 28. The camera 28 is embedded in the sensor groove 24. The cable 18 passes through the sensor cavity 46.
[0035] The top tip 6 has four wire pulling grooves 30 on the base end side of the outer peripheral surface. Each wire pulling groove 30 has a narrow width portion 32 extending axially from the base end of the top tip 6, and a wide width portion 34 located at the top end of the narrow width portion 32 and having a width wider than the narrow width portion 32. The base end of the narrow width portion 32 is connected to the wire pulling cavity 44. The wire pulling groove 30 is for inserting the wire 56. The wire pulling groove 30 has a small diameter portion 58 and a large diameter portion 60. The small diameter portion 58 extends in the wire pulling cavity 44, and the top end side of the small diameter portion 58 protrudes from the wire pulling cavity 44 and is inserted into the narrow width portion 32. The large diameter portion 60 is located at the top end of the small diameter portion 58 and is inserted into the wide width portion 34. When the wire 56 is pulled toward the base end side by operating the operating knobs 10 and 12, the large diameter portion 60 is stuck in the step between the wide width portion 34 and the narrow width portion 32, so that the displacement toward the base end side is restricted. Thus, the distal end region 2A can be bent by the pulling operation of the wire 56 .
[0036] The top tip 6 has two second through holes 36 extending from the top side to the base side. The base side of one of the second through holes 36 is connected to the fluid chamber 48 of one side. The base side of the other second through hole 36 is connected to the fluid chamber 48 of the other side. It should be noted that the base side portion of the second through hole 36 of this embodiment is exposed on the outer peripheral surface of the top tip 6. That is, the base side portion of the second through hole 36 is groove-shaped.
[0037] Next, the structure of the catheter shaft 2 will be described in detail. Figure 4 This is a cross-sectional view of the catheter shaft 2 according to the first embodiment. Figure 5 (A) is along Figure 4 Cross-sectional view along line AA. Figure 5 (B) is along Figure 4 Cross-sectional view of line BB. Figure 4 , a cross section orthogonal to the axis of the catheter shaft 2 is shown. Figure 5 (A) and Figure 5 (B) shows a cross section parallel to the axis. Figure 5 (A) and Figure 5 In (B), the cable 18 and the wire 56 are omitted from illustration.
[0038] The catheter shaft 2 includes an outer layer 38 and an inner layer 40 covered by the outer layer 38. In addition, the inner layer 40 includes a working channel 42, four wire lumens 44, a sensor lumen 46, and two fluid lumens 48. These channels and lumens are enclosed in the inner layer 40 and separated from each other.
[0039] The outer layer 38 is a tubular member having a single lumen structure. The inner layer 40 is a tubular member having a multi-lumen structure. The inner layer 40 is accommodated in the outer layer 38. The tip of the inner layer 40 is located closer to the base end of the catheter shaft 2 than the tip of the outer layer 38. The tip tip 6 is inserted into the concave portion of the inner layer 40 at the tip of the catheter shaft 2.
[0040] As the raw material of the outer layer 38, there are exemplified synthetic resins such as polyether block amide (PEBAX) having good sliding properties, mechanical strength, flexibility and biocompatibility. As the raw material of the inner layer 40, there are exemplified synthetic resins such as polyolefins, polyamides, polyether block amides, polyurethanes, nylons, polyesters, etc. Contrast agents, pigments, etc. may also be mixed into the constituent materials of the outer layer 38 and the inner layer 40. The hardness of the outer layer 38 and the inner layer 40 may be different. For example, the hardness of the outer layer 38 is higher than that of the inner layer 40. It should be noted that sometimes the hardness of the inner layer 40 is higher than that of the outer layer 38, and sometimes the hardness of the inner layer 40 is the same as the hardness of the outer layer 38.
[0041] The outer layer 38 has a first reinforcement layer 50 on the inner circumference. In the present embodiment, the first reinforcement layer 50 is considered to be a part of the outer layer 38. As an example, the first reinforcement layer 50 is composed of a coil obtained by winding a wire into a spiral shape. It should be noted that the first reinforcement layer 50 can also be composed of a braided member obtained by braiding a plurality of wires into a cylindrical shape. Examples of raw materials for the wire include biocompatible metals such as tungsten, stainless steel, nickel titanium, nylon, polyetheretherketone (PEEK), liquid crystal polymers and other biocompatible materials. The outer layer 38 has the first reinforcement layer 50, so it is easy to maintain the shape of the channel or cavity enclosed in the inner layer 40. It should be noted that in Figure 4 , the first reinforcement layer 50 is schematically shown.
[0042] The working channel 42 is a tube extending from the base end to the top end of the catheter shaft 2, and is a passage for inserting or removing a treatment instrument relative to the working channel port 14. Examples of treatment instruments include forceps, cannulas, dilators, guide wires, snares, injection needles, high-frequency knives, stents, etc. It should be noted that there may be more than two working channels 42. The working channel 42 is formed by a working channel tube 52 buried in the inner layer 40. That is, the inner side surface of the working channel tube 52 divides the working channel 42, and the internal space of the working channel tube 52 becomes the working channel 42.
[0043] The base end of the working channel tube 52 communicates with the working channel port 14. The top end of the working channel tube 52 communicates with the first through hole 22. Examples of the material of the working channel tube 52 include synthetic resins having good sliding properties such as polytetrafluoroethylene (PTFE) and perfluoroalkoxyalkane (PFA).
[0044] The inner layer 40 has a second reinforcement layer 54 surrounding the working channel 42. The inner layer 40 of this embodiment has a second reinforcement layer 54 at the interface with the working channel tube 52. The second reinforcement layer 54 does not contact the outer layer 38. That is, the inner layer 40 is sandwiched between the second reinforcement layer 54 and the outer layer 38. The second reinforcement layer 54 is composed of a coil or a braided member, for example, like the first reinforcement layer 50. The inner layer 40 has the second reinforcement layer 54, which makes it easy to maintain the shape of the working channel 42. It should be noted that in Figure 4 , the second reinforcement layer 54 is schematically shown.
[0045] The four wire pulling cavities 44 are tubes extending from the base end to the top end of the catheter shaft 2, through which the wire pulling 56 is passed and accommodated. It should be noted that the number of the wire pulling cavities 44 only needs to be at least four, but preferably four. Each wire pulling cavity 44 is formed by a wire pulling cavity tube 62 buried in the inner layer 40. That is, the inner side surface of the wire pulling cavity tube 62 divides the wire pulling cavity 44, and the internal space of each wire pulling cavity tube 62 becomes the wire pulling cavity 44.
[0046] The base end of each wire pull lumen 62 is communicated with the operation knob 10 or the operation knob 12. The top end of each wire pull lumen 62 is communicated with the wire pull groove 30. The material of the wire pull lumen 62 is the same as that of the working channel tube 52, for example.
[0047] The sensor cavity 46 is a tube extending from the base end to the top end of the catheter shaft 2, through which at least a portion of the sensor is passed and accommodated. In the present embodiment, the cable 18 passes through the sensor cavity 46 as a part of the sensor. Examples of the cable 18 include a power cable and a signal cable. It should be noted that the sensor itself can also pass through the sensor cavity 46. As sensors mounted on the catheter 1, in addition to the camera module 26, examples include thermocouples, ultrasonic sensors, optical sensors, pressure sensors, etc. It should be noted that there can be more than two sensor cavities 46. The sensor cavity 46 is formed by a sensor cavity tube 64 buried in the inner layer 40. That is, the inner side surface of the sensor cavity tube 64 divides the sensor cavity 46, and the internal space of the sensor cavity tube 64 becomes the sensor cavity 46.
[0048] The base end of the sensor lumen 64 communicates with the sensor port 16. The top end of the sensor lumen 64 communicates with the sensor groove 24. The material of the sensor lumen 64 is the same as that of the working channel tube 52, for example.
[0049] The two fluid cavities 48 are tubes extending from the base end to the top end of the catheter shaft 2, and are passages for fluid flow. Examples of fluids flowing in the fluid cavities 48 include physiological saline supplied to the treatment site, body fluids (blood, tissue fluid) recovered from the treatment site, etc. It should be noted that the fluid cavities 48 can be one or more than three, and sometimes omitted. Each fluid cavity 48 is formed by a fluid cavity tube 66 buried in the inner layer 40. That is, the inner side surface of the fluid cavity tube 66 divides the fluid cavity 48, and the internal space of each fluid cavity tube 66 becomes the fluid cavity 48.
[0050] The base end of each fluid lumen 66 is connected to the fluid port. The top end of each fluid lumen 66 is connected to the second through hole 36. The physiological saline delivered to the top end side of the catheter shaft 2 via the fluid lumen 48 is discharged from the second through hole 36, thereby cleaning the treatment site. In addition, the body fluid retained in the treatment site is sucked from the second through hole 36 and the body fluid is recovered to the base end side of the catheter shaft 2 via the fluid lumen 48, thereby also cleaning the treatment site. In this way, the field of view of the camera module 26 can be ensured, and then the field of view of the therapist can be ensured. The raw material of the fluid lumen 66 is, for example, the same as the raw material of the working channel tube 52.
[0051] Next, the configuration of the channels and cavities contained in the inner layer 40 will be described. The working channel 42 and the working channel tube 52 are eccentric with respect to the axis C1 of the catheter shaft 2. That is, the axis C2 of the working channel 42 and the working channel tube 52 is offset with respect to the axis C1 of the catheter shaft 2. It should be noted that the axis C1 of the catheter shaft 2 is substantially the same as the axis of the outer layer 38.
[0052] Furthermore, in a cross-sectional view perpendicular to the axis of the catheter shaft 2, the shortest distance from the outer circumference of the outer layer 38 to the portion 42A of the working channel 42 closest to the outer circumference of the outer layer 38 is longer than the shortest distance from the outer circumference of the outer layer 38 to the portion 44A of each wire lumen 44 closest to the outer circumference of the outer layer 38, longer than the shortest distance from the outer circumference of the outer layer 38 to the portion 46A of the sensor lumen 46 closest to the outer circumference of the outer layer 38, and longer than the shortest distance from the outer circumference of the outer layer 38 to the portion 48A of the fluid lumen 48 closest to the outer circumference of the outer layer 38. That is, although the axis C2 of the working channel 42 is offset from the axis C1 of the catheter shaft 2, it is located closer to the axis C1 than the axes of the wire lumen 44, the sensor lumen 46, and the fluid lumen 48. When there are more than two working channels 42, more than five wire pulling cavities 44, more than two sensor cavities 46, or one or more than three fluid cavities 48, each channel and each cavity are also configured in a manner that satisfies the above-mentioned positional relationship.
[0053] In addition, in a cross-sectional view perpendicular to the axis of the catheter shaft 2, each of the pull-wire lumen 62, the sensor lumen 64, and the fluid lumen 66 is in contact with the outer layer 38, and the working channel tube 52 does not contact the outer layer 38. It should be noted that the outer layer 38 of this embodiment has a first reinforcement layer 50 on the surface facing the inner layer 40. Therefore, each of the pull-wire lumen 62, the sensor lumen 64, and the fluid lumen 66 is in contact with the first reinforcement layer 50, and the working channel tube 52 does not contact the first reinforcement layer 50. That is, although the axis C2 of the working channel tube 52 is offset relative to the axis C1 of the catheter shaft 2, it is located at a position closer to the axis C1 than the axis of each of the pull-wire lumen 62, the sensor lumen 64, and the fluid lumen 66.
[0054] In the present embodiment, "the tube is in contact with the outer layer 38 or the first reinforcing layer 50" means that the inner layer 40 is not sandwiched between the tube and the outer layer 38 or the first reinforcing layer 50. In addition, "the tube does not contact the outer layer 38 or the first reinforcing layer 50" means that the inner layer 40 is sandwiched between the tube and the outer layer 38 or the first reinforcing layer 50. It should be noted that in the manufacturing process of the catheter shaft 2, the resin component constituting the outer layer 38 and the resin component constituting the inner layer 40 may melt and mix. In the present embodiment, at the boundary between the outer layer 38 and the inner layer 40, the portion where the resin components of the two layers are mixed is included in the outer layer 38.
[0055] When the working channel 42 is eccentric with respect to the axis C1 of the catheter shaft 2, a thin-walled portion of the inner layer 40 sandwiched between the working channel 42 and the outer layer 38 is easily formed. As a result of repeated in-depth studies by the present inventors, it was found that if there is a thin-walled portion, wrinkles may sometimes be generated on the side wall of the working channel 42 when the catheter shaft 2 is bent, or the wrinkles that can be generated become larger. In particular, it was confirmed that: when the thickness of the thin-walled portion is less than 0.28 mm, the tendency to form wrinkles increases, and as the thickness becomes thinner, the wrinkles formed become larger. When the thickness of the thin-walled portion is less than 0.1 mm, the wrinkles formed become significantly larger. When the wrinkles generated in the working channel 42 become larger, it is difficult to insert and remove the disposal instrument, and the operability of the disposal instrument may be reduced. This problem was discovered for the first time by the present inventors and cannot be understood as the general understanding of those skilled in the art.
[0056] As a countermeasure to such a problem, by configuring the working channel 42 as described above, it is possible to suppress the formation of a thin-walled portion around the working channel 42, and suppress the generation of wrinkles. Alternatively, it is possible to suppress the formation of wrinkles. As a result, it is possible to improve the ease of insertion and removal of the treatment instrument relative to the working channel 42. In addition, this can improve the operability of the craftsman using the catheter 1.
[0057] In addition, by making the axis C2 of the working channel 42 close to the axis C1 of the catheter shaft 2, it is easy to ensure the installation space of the second reinforcement layer 54. And, by providing the second reinforcement layer 54, the generation of wrinkles or the enlargement of wrinkles can be further suppressed. In addition, by making the axis C2 of the working channel 42 close to the axis C1 of the catheter shaft 2, the treatment instrument can easily enter the field of view of the camera module 26. Thus, it is easier to operate the treatment instrument. It should be noted that in the description of the generation or enlargement of wrinkles and the suppression of the generation or enlargement of wrinkles, the working channel 42 can also be replaced by the working channel tube 52.
[0058] In the present embodiment, the camera head 28 is fixed to the distal tip 6 and is not inserted into the sensor cavity 46. Therefore, only the cable 18 is inserted into the sensor cavity 46. Therefore, the diameter of the sensor cavity 46 can be reduced compared to the case where the entire camera module 26 is inserted into the sensor cavity 46 for the purpose of reusing the camera module 26, for example. As a result, the axis C2 of the working channel 42 and the working channel tube 52 can be easily brought closer to the axis C1 of the catheter shaft 2.
[0059] Furthermore, in a cross-sectional view perpendicular to the axis of the catheter shaft 2, the working channel 42, the wire lumen 44, and the sensor lumen 46 have substantially perfect circular shapes, whereas the fluid lumen 48 has a long hole shape. This can prevent the arrangement design that brings the axis C2 of the working channel 42 and the working channel tube 52 close to the axis C1 of the catheter shaft 2 from being hindered by the fluid lumen 48, and the cross-sectional area of the fluid lumen 48 can be increased to easily ensure the flow rate of the fluid.
[0060] Furthermore, by making the axis C2 of the working channel 42 and the working channel tube 52 close to the axis C1 of the catheter shaft 2 , it is easy to evenly arrange the four wire pulling lumens 44 in the circumferential direction of the catheter shaft 2 . Figure 6 4 is a diagram for explaining the configuration of the wire pulling cavity 44. Figure 6 , the cable 18 and the pull wire 56 are omitted. In the present embodiment, in a cross-sectional observation perpendicular to the axis of the catheter shaft 2, when four imaginary lines are assumed to connect the axis C1 of the catheter shaft 2 and the axis C3 of each pull wire lumen, the difference between the angle formed by two imaginary lines adjacent in the circumferential direction and each other angle is preferably 35° or less, more preferably 30° or less, and further preferably 25° or less.
[0061] Specifically, connect the axis C1 with Figure 6 The imaginary line of the axis C3 of the wire pulling cavity 44 located at the upper left in the figure is set as the imaginary line L1. Figure 6 The imaginary line of the axis C3 of the wire pulling cavity 44 located at the upper right in the figure is set as the imaginary line L2. Figure 6The imaginary line of the axis C3 of the wire pulling cavity 44 located at the lower right side is set as the imaginary line L3. Figure 6 The imaginary line of the axis C3 of the wire pulling cavity 44 located at the lower left in the figure is set as the imaginary line L4. In addition, the angle formed by the imaginary line L1 and the imaginary line L2 is set as angle θ1. In addition, the angle formed by the imaginary line L2 and the imaginary line L3 is set as angle θ2. In addition, the angle formed by the imaginary line L3 and the imaginary line L4 is set as angle θ3. In addition, the angle formed by the imaginary line L4 and the imaginary line L1 is set as angle θ4. At this time, the difference between the angles θ1 to θ4 and each other angle is less than 35°.
[0062] For example, when the diameter of the catheter shaft 2 is 3.8 mm and the diameter of the working channel 42 is 2 mm, the difference between the angles θ1 to θ4 can be made substantially 0. Also, when the diameter of the catheter shaft 2 is 3.1 mm and the diameter of the working channel 42 is 1.2 mm, the difference between the angles θ1 to θ4 can be made 15° or less.
[0063] By configuring the wire pull cavity 44 in this way, it is possible to suppress the difference in the bending state of the tip region 2A and the operating feel of the operation knobs 10 and 12 caused by the different directions of the bending tip region 2A. As a result, the operability of the catheter 1 can be improved. It should be noted that the four wire pull cavities 44 are arranged at approximately the same distance from the axis C1 of the catheter shaft 2. For example, in a cross-sectional view perpendicular to the axis of the catheter shaft 2, the difference in the distance from the axis C1 to the axis C3 of each wire pull cavity 44 is less than 15% relative to the radius of the catheter shaft 2.
[0064] Regarding the configuration of the above-mentioned channels and cavities and the configuration of the various tubes, it is sufficient that at least a portion of the catheter shaft 2 in the axial direction of the catheter shaft 2 satisfies the requirements, but it is preferred that at least a portion of the top end region 2A satisfies the requirements, it is more preferred that the region including the apex of the curve in the top end region 2A satisfies the requirements, and it is further preferred that the entire top end region 2A satisfies the requirements.
[0065] The catheter shaft 2 is configured as an integrally molded product. The molding method for obtaining the integrally molded product is not particularly limited. In an example of a method for manufacturing the catheter shaft 2, first, the working channel tube 52, the wire lumen 62, the sensor lumen 64, and the fluid lumen 66 are prepared in a state of being arranged on the outer periphery of the mandrel. At this time, each tube prepared in advance can be sleeved on the mandrel, or each tube can be formed on the outer periphery of the mandrel by extrusion molding.
[0066] Next, a second reinforcement layer 54 is formed on the outer periphery of the working channel tube 52. For example, a wire is fed from a braiding machine and wound around the outer periphery of the working channel tube 52, thereby forming a coil-shaped second reinforcement layer 54. Next, the molten resin constituting the inner layer 40 is extruded from an extruder, and the inner layer 40 is extruded in a manner that buries each tube. Next, a first reinforcement layer 50 is formed on the outer periphery of the inner layer 40. For example, a wire is fed from a braiding machine and wound around the outer periphery of the inner layer 40, thereby forming a coil-shaped first reinforcement layer 50. At this time, the molten resin constituting the outer layer 38 is extruded from an extruder, and the outer layer 38 is extruded in a manner that covers the inner layer 40. The catheter shaft 2 is obtained through the above steps.
[0067] (Implementation Method 2)
[0068] The catheter 1 of this embodiment has substantially the same configuration as the catheter 1 of Embodiment 1, except that the fluid chamber 48 has an additional function. Hereinafter, the catheter 1 of Embodiment 2 will be described with a focus on the configurations different from Embodiment 1, and the common configurations will be briefly described or omitted.
[0069] Figure 7 This is a cross-sectional view of the catheter shaft 2 according to the second embodiment. Figure 7 2 shows a cross section perpendicular to the axis of the catheter shaft 2. Figure 7 In the figure, the cable 18 and the pull wire 56 are omitted.
[0070] In the catheter shaft 2 of the present embodiment, in a cross-sectional observation orthogonal to the axis of the catheter shaft 2, the shortest distance between the portion 42A of the working channel 42 closest to the outer peripheral surface of the outer layer 38 and the outer peripheral surface of the outer layer 38 is longer than the shortest distance between the portion 44A of each pull-wire cavity 44 closest to the outer peripheral surface of the outer layer 38 and the outer peripheral surface of the outer layer 38, is longer than the shortest distance between the portion 46A of the sensor cavity 46 closest to the outer peripheral surface of the outer layer 38 and the outer peripheral surface of the outer layer 38, and is longer than the shortest distance between the portion 48A of the fluid cavity 48 closest to the outer peripheral surface of the outer layer 38 and the outer peripheral surface of the outer layer 38 (refer to FIG. Figure 4 ).
[0071] In addition, in a cross-sectional view perpendicular to the axis of the catheter shaft 2, each of the pull-wire lumens 62, the sensor lumens 64, and the fluid lumens 66 are connected to the outer layer 38, and the working channel tube 52 does not contact the outer layer 38. In addition, each of the pull-wire lumens 62, the sensor lumens 64, and the fluid lumens 66 are connected to the first reinforcement layer 50, and the working channel tube 52 does not contact the first reinforcement layer 50.
[0072] In addition, the fluid cavity 48 of the present embodiment also serves as a guidewire cavity for the guidewire 68 to pass through. In the case where the catheter shaft 2 does not have a guidewire cavity, the guidewire 68 will pass through the working channel 42. However, if the guidewire 68 and the treatment instrument are passed through the working channel 42 at the same time, the guidewire 68 may interfere with the insertion and removal and operation of the treatment instrument, so it is ideal to avoid simultaneous insertion. Therefore, the guidewire 68 passing through the working channel 42 will be temporarily pulled out and the treatment instrument will be passed through, or the opposite operation will occur. As a result, the operability of the craftsmanship using the catheter 1 may be reduced.
[0073] In contrast, if the fluid and the guide wire 68 pass through the fluid cavity 48 at the same time, they will not interfere with each other or the degree of interference is low. Therefore, the fluid cavity 48 can be used as a guide wire cavity. In addition, by using the fluid cavity 48 as a guide wire cavity, the operability of the craftsman using the catheter 1 can be improved.
[0074] The fluid cavity 48 of this embodiment has a substantially perfect circular shape in a cross-sectional view perpendicular to the axis of the catheter shaft 2. Usually, the cross-sectional shape of the guide wire 68 is substantially perfect circular. Therefore, by making the cross section of the fluid cavity 48 substantially perfect circular, it is easier to avoid the guide wire 68 from contacting the side wall of the fluid cavity 48, compared with the case where the cross section is a long hole shape as in the first embodiment.
[0075] Even when the cross section of the fluid cavity 48 is made substantially circular, the difference between the angles θ1 to θ4 formed by the imaginary lines L1 to L4 can be made 35° or less. For example, when the diameter of the catheter shaft 2 is 3.8 mm, the diameter of the working channel 42 is 2 mm, the diameter of one fluid cavity 48 is 0.85 mm, and the diameter of the other fluid cavity 48 is 0.8 mm, the difference between the angles θ1 to θ4 can be made 32° or less.
[0076] The embodiments of the present disclosure have been described in detail above. The above embodiments only show specific examples when the present disclosure is implemented. The contents of the embodiments do not limit the technical scope of the present disclosure, and many design changes such as changes, additions, and deletions of constituent elements can be made within the scope of the idea of the present disclosure specified in the claims. The new embodiment with added design changes has the effects of the combined embodiments and deformations. In the above embodiments, expressions such as "in this embodiment" and "in this embodiment" are added to emphasize the content that can make such design changes, but even if there are no such expressions, design changes are allowed. Any combination of the constituent elements included in each embodiment is also valid as a scheme of the present disclosure. The hatched lines marked in the cross-section of the accompanying drawings do not limit the material of the objects marked with hatched lines.
[0077] The embodiment can also be determined by the items described below.
[0078] [First item]
[0079] A catheter shaft (2) comprises:
[0080] an outer layer (38); and
[0081] The inner layer (40) is covered by the outer layer (38),
[0082] The inner layer (40) is provided with at least one working channel (42) for a treatment instrument to pass through, at least four pull wire cavities (44) for a pull wire (56) to pass through, and at least one sensor cavity (46) for at least a portion of a sensor (18) to pass through.
[0083] The working channel (42) is eccentric relative to the axis (C1) of the catheter shaft (2),
[0084] In at least a portion of the catheter shaft (2), when viewed in a cross-section perpendicular to the axis of the catheter shaft (2), the shortest distance between a portion (42A) of the working channel (42) closest to the outer peripheral surface of the outer layer (38) and the outer peripheral surface of the outer layer (38) is longer than the shortest distance between a portion (44A) of the pull-wire cavity (44) closest to the outer peripheral surface of the outer layer (38) and the outer peripheral surface of the outer layer (38), and is longer than the shortest distance between a portion (46A) of the sensor cavity (46) closest to the outer peripheral surface of the outer layer (38) and the outer peripheral surface of the outer layer (38).
[0085] [Second item]
[0086] The catheter shaft (2) according to the first item, wherein:
[0087] The inner layer (40) is provided with at least one fluid cavity (48) for fluid to flow through.
[0088] In at least a portion, when observed in cross-section, the shortest distance between a portion (42A) of the working channel (42) closest to the outer peripheral surface of the outer layer (38) and the outer peripheral surface of the outer layer (38) is longer than the shortest distance between a portion (48A) of the fluid cavity (48) closest to the outer peripheral surface of the outer layer (38) and the outer peripheral surface of the outer layer (38).
[0089] [Third Item]
[0090] A catheter shaft (2) comprises:
[0091] an outer layer (38); and
[0092] The inner layer (40) is covered by the outer layer (38),
[0093] The inner layer (40) is provided with at least one working channel tube (52) forming a working channel (42) for a treatment instrument to pass through, at least four wire puller tubes (62) forming wire puller tubes (44) for a wire puller (56) to pass through, and at least one sensor tube (64) forming a sensor cavity (46) for at least a portion of a sensor (18) to pass through.
[0094] The working channel tube (52) is eccentric relative to the axis (C1) of the catheter shaft (2).
[0095] In at least a portion of the catheter shaft (2), in a cross-sectional view perpendicular to the axis of the catheter shaft (2), each pull wire lumen (62) and the sensor lumen (64) are connected to the outer layer (38), and the working channel tube (52) does not contact the outer layer (38).
[0096] [Fourth Item]
[0097] The catheter shaft (2) according to the third item, wherein:
[0098] The outer layer (38) has a first reinforcement layer (50) on the inner peripheral surface.
[0099] In at least a portion, each of the pull wire lumens (62) and the sensor lumens (64) is connected to the first reinforcement layer (50), and the working channel tube (52) does not contact the first reinforcement layer (50).
[0100] [Fifth Item]
[0101] The catheter shaft (2) according to the third item or the fourth item, wherein:
[0102] The inner layer (40) is provided with at least one fluid cavity tube (66) forming a fluid cavity (48) for fluid to flow through.
[0103] In at least a portion, the fluid lumen (66) is in contact with the outer layer (38) when viewed in cross-section.
[0104] [Sixth Item]
[0105] The catheter shaft (2) according to the fifth item, wherein:
[0106] The outer layer (38) has a first reinforcement layer (50) on the inner peripheral surface.
[0107] In at least a portion, the fluid lumen (66) is adjacent to the first reinforcement layer (50).
[0108] [Seventh Item]
[0109] The catheter shaft (2) according to any one of the first to sixth items, wherein:
[0110] The inner layer (40) has a second reinforcement layer (54) surrounding the working channel (42).
[0111] [Item 8]
[0112] The catheter shaft (2) according to any one of the first to seventh items, wherein:
[0113] Under cross-sectional observation, when four imaginary lines (L1 to L4) are assumed to connect the axis (C1) of the catheter shaft (2) and the axis (C3) of each pull-wire cavity (44), the difference between the angle (θ1 to θ4) formed by two circumferentially adjacent imaginary lines (L1 to L4) and any other angle is less than 35°.
[0114] [Item 9]
[0115] The catheter shaft (2) according to the second item, the fifth item or the sixth item, wherein:
[0116] The fluid chamber (48) also serves as a guide wire chamber for a guide wire (68) to pass through.
[0117] [Item 10]
[0118] The catheter shaft (2) according to any one of the first to ninth items, wherein:
[0119] At least a portion includes at least a portion of a tip region (2A) of the catheter shaft (2).
[0120] [Item 11]
[0121] A catheter (1) comprising:
[0122] The catheter shaft (2) as described in any one of the first to tenth items; and
[0123] The handle (4) is located at the base end side of the catheter shaft (2).
[0124] Description of Reference Numerals
[0125] 1: catheter; 2: catheter shaft; 4: handle; 38: outer layer; 40: inner layer; 42: working channel; 44: pull-wire cavity; 46: sensor cavity; 48: fluid cavity; 50: first reinforcement layer; 52: working channel tube; 54: second reinforcement layer; 62: pull-wire cavity tube; 64: sensor cavity tube; 66: fluid cavity tube.
Claims
1. A catheter shaft comprising: Outer layer; and an inner layer, covered by said outer layer, The inner layer is provided with at least one working channel for a treatment instrument to pass through, at least four wire drawing cavities for wires to pass through, and at least one sensor cavity for at least a part of a sensor to pass through. The working channel is eccentric relative to the axis of the catheter shaft, In at least a portion of the catheter shaft, under a sectional observation orthogonal to the axis of the catheter shaft, the shortest distance between a portion of the working channel closest to the outer circumferential surface of the outer layer and the outer circumferential surface of the outer layer is longer than the shortest distance between a portion of each of the pull wire cavities closest to the outer circumferential surface of the outer layer and the outer circumferential surface of the outer layer, and is longer than the shortest distance between a portion of the sensor cavity closest to the outer circumferential surface of the outer layer and the outer circumferential surface of the outer layer.
2. The catheter shaft of claim 1, wherein: At least one fluid cavity for fluid flow is provided in the inner layer, In at least a portion of the catheter shaft, under the cross-sectional observation, the shortest distance between a portion of the working channel closest to the outer circumferential surface of the outer layer and the outer circumferential surface of the outer layer is longer than the shortest distance between a portion of the fluid cavity closest to the outer circumferential surface of the outer layer and the outer circumferential surface of the outer layer.
3. A catheter shaft comprising: Outer layer; and an inner layer, covered by said outer layer, The inner layer is provided with at least one working channel tube forming a working channel for a treatment instrument to pass through, at least four wire pulling lumen tubes forming a wire pulling lumen for a wire to pass through, and at least one sensor lumen tube forming a sensor lumen for at least a part of a sensor to pass through. The working channel tube is eccentric relative to the axis of the catheter shaft, In at least a portion of the catheter shaft, in a cross-sectional view perpendicular to the axis of the catheter shaft, each of the pull wire lumens and the sensor lumen is in contact with the outer layer, and the working channel tube does not contact the outer layer.
4. The catheter shaft of claim 3, wherein: The outer layer has a first reinforcement layer on the inner circumference, In at least a portion of the catheter shaft, each of the pull wire lumen and the sensor lumen is connected to the first reinforcement layer, and the working channel tube does not contact the first reinforcement layer.
5. The catheter shaft of claim 3, wherein: The inner layer is provided with at least one fluid cavity tube forming a fluid cavity for fluid to flow through. In at least a portion of the catheter shaft, the fluid lumen is in contact with the outer layer in the cross-sectional view.
6. The catheter shaft of claim 5, wherein: The outer layer has a first reinforcement layer on the inner circumference, The fluid lumen is in contact with the first reinforcement layer in at least a portion of the catheter shaft.
7. The catheter shaft according to any one of claims 1 to 6, wherein: The inner layer has a second reinforcement layer surrounding the working channel.
8. The catheter shaft according to any one of claims 1 to 6, wherein: In the cross-sectional observation, when four imaginary lines connecting the axis of the catheter shaft and the axis of each of the wire pulling lumens are assumed, the difference between the angle formed by two adjacent imaginary lines in the circumferential direction and each other angle is 35° or less.
9. The catheter shaft according to claim 2 or 5, wherein: The fluid cavity also serves as a guide wire cavity for the guide wire to pass through.
10. The catheter shaft according to any one of claims 1 to 6, wherein: The at least portion of the catheter shaft includes at least a portion of a tip region of the catheter shaft.
11. A catheter comprising: The catheter shaft of any one of claims 1 to 6; and The handle is located at the base end side of the catheter shaft.