Incision instrument

Abstract

To smoothly change an orientation of an exposed part of a knife wire to a desired orientation by rotating a support member while maintaining inner and outer diameters of a tube and an outer diameter of the knife wire.SOLUTION: An incision instrument includes: a tube having a lumen; a knife wire housed in the lumen; and a support member for rotatably supporting a base end of the knife wire. The knife wire has an exposed portion exposed to the outside of the tube through a hole communicating with the lumen at least when the tube is in a predetermined posture, between a tip and a base end of the tube. The tube has a first high stiffness portion and a low stiffness portion located on the tip side of the first high stiffness portion. The low stiffness portion includes a portion formed from a material exhibiting an elastic modulus smaller than an elastic modulus of a material forming the first high stiffness portion.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The technology disclosed herein relates to dissection instruments. [Background technology]

[0002] Endoscopic sphincterotomy (EST) is known as a treatment for common bile duct stones. In EST, an incision instrument is inserted into the papilla, which corresponds to the outlet of the bile duct and pancreatic duct, and the biological tissue is incised with the incision instrument.

[0003] An incision instrument used in endoscopic papillotomy comprises a tube with a lumen, a knife wire (cutting wire) housed in the lumen, and a support member that rotatably supports the base end of the knife wire (see, for example, Patent Document 1). A portion of the knife wire (hereinafter referred to as the "exposed portion") is exposed to the outside of the tube at all times or when the tube is in a specified position. By applying a high-frequency current to the knife wire from a high-frequency power source, biological tissue can be incised by the exposed portion of the knife wire.

[0004] The operator rotates the support member to incise a predetermined shape in a predetermined area of ​​the biological tissue of the papilla. This generates a rotational torque at the base end of the knife wire supported by the support member, and the rotational torque is transmitted to the tube via the knife wire. As a result, the tube rotates around its central axis, and the orientation of the exposed part of the knife wire changes to the desired orientation. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 4896351 Summary of the Invention [Problem to be solved by the invention]

[0006] In conventional incision instruments, the torsional rigidity of the tube is high, so that even if the operator applies a rotational torque to the base end of the knife wire by rotating the support member, the tube does not rotate smoothly, and the orientation of the exposed part of the knife wire cannot be smoothly changed to the desired orientation. It is possible to reduce the torsional rigidity of a part of the tube by making the diameter of the part thinner, but in that case, the inner and outer diameters of the part become thinner and it is not possible to form a lumen of a required size. It is also possible to increase the outer diameter of the knife wire to improve the rotational torque transmission, but increasing the outer diameter of the knife wire may reduce the incision ability of the knife wire.

[0007] Thus, conventional cutting instruments have the problem that it is not possible to smoothly change the orientation of the exposed portion of the knife wire to a desired orientation by rotating the support member while maintaining the inner and outer diameters of the tube and the outer diameter of the knife wire.

[0008] Furthermore, these issues are not limited to cutting instruments used in endoscopic nipple resection to cut the nipple, but are common to all cutting instruments that are inserted into various organs within the human body, such as the vascular system, lymphatic system, biliary system, urinary system, respiratory system, digestive system, secretory glands, and reproductive organs, to cut biological tissue.

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

[0010] The technology disclosed in this specification can be realized, for example, in the following forms.

[0011] (1) The incision instrument disclosed in this specification comprises a tube having a lumen, a knife wire housed in the lumen, and a support member rotatably supporting a base end of the knife wire. The knife wire has an exposed portion between the tip and base ends of the tube that is exposed to the outside of the tube through a hole that communicates with the lumen at least when the tube is in a predetermined position. The tube has a first high stiffness portion and a low stiffness portion located distally of the first high stiffness portion. The low stiffness portion includes a portion formed from a material exhibiting an elastic modulus smaller than that of a material forming the first high stiffness portion.

[0012] In this incision instrument, the tube has a low-rigidity section located more distal than the first high-rigidity section, and the low-rigidity section includes a section formed from a material exhibiting an elastic modulus smaller than that of the material forming the first high-rigidity section. Therefore, according to this incision instrument, the presence of the low-rigidity section can reduce the torsional rigidity of the section of the tube relatively distal to the tip, and the orientation of the exposed portion of the knife wire can be smoothly changed to a desired orientation by rotating the support member while maintaining the inner and outer diameters of the tube and the outer diameter of the knife wire.

[0013] (2) In the above incision instrument, the tube may further have a second high-rigidity portion located distally of the low-rigidity portion, the low-rigidity portion including a portion made of a material exhibiting an elastic modulus smaller than that of the material forming the second high-rigidity portion. By adopting this configuration, the presence of the second high-rigidity portion can make the torsional rigidity of the portion distally of the low-rigidity portion relatively large, improving operability during delivery of the incision instrument while allowing the orientation of the exposed portion of the knife wire to be more smoothly changed to a desired orientation by rotating the support member.

[0014] (3) In the above incision instrument, at least a portion of the low rigidity portion may be formed in a first portion of the tube that exposes the exposed portion of the knife wire. By adopting this configuration, the torsional rigidity of the first portion of the tube that exposes the exposed portion of the knife wire can be effectively reduced, and the orientation of the exposed portion of the knife wire can be changed more smoothly by rotating the support member. In addition, the bending rigidity of the first portion of the tube can be effectively reduced, and operability can be improved when bending the tube and making an incision with the exposed portion of the knife wire.

[0015] (4) In the above-mentioned incision instrument, the minimum diameter of the exposed portion of the knife wire may be 0.15 mm or more and 0.30 mm or less. By adopting this configuration, it is possible to achieve both an improvement in the rotational torque transmissibility of the knife wire and an improvement in the incision ability of the knife wire.

[0016] The technology disclosed in this specification can be realized in various forms, such as a cutting instrument, a system including a cutting instrument, and methods of manufacturing these devices and systems. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is an explanatory diagram illustrating a schematic configuration of an incision instrument 100 according to a first embodiment. [Diagram 2] FIG. 2 is an explanatory diagram showing a cross-sectional configuration of the incision instrument 100 taken along the line II-II in FIG. [Diagram 3] FIG. 1 is an explanatory diagram showing the configuration of a vertical cross section of the tip of the incision instrument 100. [Figure 4] FIG. 1 is a perspective view showing the external configuration of the tip of an incision instrument 100. [Diagram 5] FIG. 1 is an explanatory diagram showing an example of a method for operating the incision instrument 100. [Figure 6] FIG. 1 is an explanatory diagram showing an example of a method for operating the incision instrument 100. [Figure 7] FIG. 13 is a perspective view showing the external configuration of the tip of the incision instrument 100a according to the second embodiment. [Figure 8] FIG. 13 is a perspective view showing the external configuration of the tip of the incision instrument 100b according to the third embodiment. [Figure 9] FIG. 13 is an explanatory diagram showing a cross-sectional configuration of the incision instrument 100b according to the third embodiment. [Figure 10] FIG. 13 is a perspective view showing the external configuration of the tip of the incision instrument 100c according to the fourth embodiment. [Figure 11] FIG. 13 is an explanatory diagram showing a cross-sectional configuration of the incision instrument 100c according to the fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] A. First embodiment: (Configuration of incision instrument 100) 1 is an explanatory diagram showing a schematic configuration of an incision instrument 100 of a first embodiment. The incision instrument 100 is an instrument for incising biological tissue, and is used, for example, in endoscopic sphincterotomy (EST) for treating choledocholithiasis. Note that the incision instrument 100 is not limited to endoscopic sphincterotomy, and may be inserted into various organs in the human body, such as the vascular system, lymphatic system, biliary system, urinary system, respiratory system, digestive system, secretory glands, and reproductive organs, to incise biological tissue.

[0019] In FIG. 1, some of the components of the incision instrument 100 are omitted as appropriate. FIG. 1 also shows X, Y, and Z axes that are orthogonal to each other. The positive side of the Z axis is the tip side (distal side) that is inserted into the body, and the negative side of the Z axis is the base side (proximal side) that is operated by a technician such as a doctor. In FIG. 1, each part of the incision instrument 100 is shown in a state in which it is approximately linearly parallel to the Z axis, but at least a part of the incision instrument 100 has flexibility to the extent that it can be curved. These points are the same in the subsequent figures. In this specification, the tip side end of the incision instrument 100 and its components are referred to as the "tip", the tip and its vicinity are referred to as the "tip portion", the base side end is referred to as the "base end", and the base end and its vicinity are referred to as the "base end portion".

[0020] The incision instrument 100 includes a tube 10, a knife wire 20, a connector 30, and a handle portion 40. Fig. 1 shows a central axis Ax of the tube 10. In this embodiment, the central axes of the connector 30 and the handle portion 40 approximately coincide with the central axis Ax of the tube 10. However, these central axes may differ from the central axis Ax of the tube 10.

[0021] FIG. 2 is an explanatory diagram showing the configuration of a cross section (XY cross section) of the incision instrument 100 at the position II-II in FIG. 1, FIG. 3 is an explanatory diagram showing the configuration of a longitudinal section (YZ cross section) of the tip of the incision instrument 100, and FIG. 4 is an oblique view showing the external configuration of the tip of the incision instrument 100.

[0022] The tube 10 is an elongated member extending along a central axis Ax. As shown in Fig. 2, the outer shape of the cross section of the tube 10 is, for example, substantially circular or substantially elliptical. The outer diameter of the tube 10 may be constant over its entire length or may vary along the longitudinal direction.

[0023] The tube 10 is formed with a device lumen 16L, a knife wire lumen 17L, and a liquid supply lumen 18L. The device lumen 16L is an inner cavity through which a combined device such as a guide wire is housed (inserted), and extends in the longitudinal direction from the tip of the tube 10 to a branched portion 19 provided at the base end of the tube 10. The knife wire lumen 17L is an inner cavity through which a knife wire 20 is housed (inserted), and extends in the longitudinal direction from the tip to the base end of the tube 10. The liquid supply lumen 18L is an inner cavity for passing a liquid such as a contrast agent or saline, and extends in the longitudinal direction from the tip to the base end of the tube 10. The outer shape of the cross section of each lumen is, for example, approximately circular or approximately elliptical. In this embodiment, as shown in Fig. 2, the diameter W16 of the device lumen 16L is larger than the diameter W17 of the knife wire lumen 17L, and the diameter W17 of the knife wire lumen 17L is larger than the diameter W18 of the liquid supply lumen 18L. The relationship between the diameters of the lumens can be changed as desired. The knife wire lumen 17L is an example of a lumen.

[0024] The tube 10 is preferably antithrombotic, flexible, and biocompatible, and may be made of, for example, a resin material or a metal material. Examples of resin materials that can be used to form the tube 10 include polyamide resin, polyolefin resin, polyester resin, polyurethane resin, silicone resin, and fluororesin. Examples of metal materials that can be used to form the tube 10 include stainless steel such as SUS304, Ni-Ti alloy, and cobalt chrome alloy.

[0025] The knife wire 20 is a long member for incising biological tissue. The knife wire 20 is housed in a knife wire lumen 17L formed in the tube 10. The tip of the knife wire 20 is fixed to the tip of the tube 10. More specifically, as shown in FIG. 3, a fixing member 80 is filled in the tip of the knife wire lumen 17L, and the tip 21 of the knife wire 20 is fixed to the tip of the tube 10 by being fixed to the fixing member 80. Also, as shown in FIG. 1, the base end 22 of the knife wire 20 extends from the base end of the knife wire lumen 17L through the inner cavity of the connector 30 to the position of the handle portion 40, and is supported by a wire support portion 45 of the handle portion 40, which will be described later.

[0026] A portion of the knife wire 20 (hereinafter, referred to as the "exposed portion 20E") is exposed to the outside of the tube 10 between the tip and base ends of the tube 10. More specifically, as shown in FIG. 3, the tube 10 is formed with a tip side hole 12 and a base side hole 13 that communicate between the knife wire lumen 17L and the outside. In the knife wire 20, a portion on the base side of the tip portion 21 fixed to the fixing member 80 in the knife wire lumen 17L is exposed to the outside of the tube 10 through the tip side hole 12, and a further base side portion is housed again in the knife wire lumen 17L through the base side hole 13. The exposed portion 20E of the knife wire 20 is a portion from the position passing through the tip side hole 12 to the position passing through the base side hole 13. The minimum diameter of the exposed portion 20E of the knife wire 20 is, for example, 0.15 mm or more and 0.30 mm or less. The minimum diameter of the exposed portion 20E of the knife wire 20 may be, for example, 0.18 mm or more and 0.25 mm or less. In this embodiment, the distal side hole 12 and the proximal side hole 13 are formed on the outer circumferential surface of the tube 10. In the following description, the portion of the tube 10 where the exposed portion 20E of the knife wire 20 is exposed is referred to as a first portion P1. The first portion P1 of the tube 10 is a portion in the longitudinal direction of the tube 10, and is a portion from the position of the distal side hole 12 to the position of the proximal side hole 13.

[0027] A high-frequency current is applied to the knife wire 20 from a high-frequency power source (not shown). The high-frequency power source is connected to the wire supporting portion 45. When the high-frequency power source is connected to the wire supporting portion 45, a conductive material such as a metal can be used as a material for forming the wire supporting portion 45. This allows the exposed portion 20E of the knife wire 20 to incise the biological tissue.

[0028] The knife wire 20 preferably has electrical conductivity, anti-thrombogenicity, and biocompatibility, and can be formed from a metallic material such as a stainless steel alloy such as SUS302, SUS304, SUS316, Ni-Ti alloy, nickel-chromium alloy, cobalt alloy, gold, platinum, tungsten, or an alloy containing these elements.

[0029] Here, the configuration of the tube 10 will be described in detail. As shown in Fig. 4, the tube 10 has a low rigidity portion 16 and a first high rigidity portion 17. The low rigidity portion 16 is located on the distal side of the first high rigidity portion 17. As shown in Figs. 1 and 4, in this embodiment, a distal end portion P2 including a first portion P1 in the tube 10 is the low rigidity portion 16, and a base end portion P3 on the proximal side of the distal end portion P2 is the first high rigidity portion 17.

[0030] The low-rigidity portion 16 of the tube 10 includes a portion formed from a material exhibiting a smaller elastic modulus than the material forming the first high-rigidity portion 17. In this embodiment, the entire low-rigidity portion 16 is formed from a material exhibiting a smaller elastic modulus than the material forming the first high-rigidity portion 17. Such a configuration is realized, for example, by forming the first high-rigidity portion 17 from a fluororesin and the low-rigidity portion 16 from a nylon-based resin or a urethane-based resin. Alternatively, such a configuration is realized, for example, by forming the first high-rigidity portion 17 from a nylon-based resin or a urethane-based resin and the low-rigidity portion 16 from a material of a grade that is a nylon-based resin or a urethane-based resin and has a lower elastic modulus than the material forming the first high-rigidity portion 17. As described above, since the first portion P1 of the tube 10 is included in the tip portion P2, it can be said that a part of the low-rigidity portion 16 is formed in the first portion P1 of the tube 10.

[0031] As shown in FIG. 4, markers 14 indicating the position of exposed portion 20E are formed on the outer surface of tube 10 near exposed portion 20E of knife wire 20. In this embodiment, one marker 14 is arranged on the distal side of exposed portion 20E, one marker 14 is arranged on the proximal side of proximal end of exposed portion 20E, and two markers 14 are arranged between the distal end and proximal end of exposed portion 20E. The number and positions of markers 14 can be changed as desired. Markers 14 do not necessarily have to be formed. In other figures, illustration of markers 14 is omitted as appropriate.

[0032] As shown in FIG. 1, the connector 30 is a tubular member connected to the base end of the tube 10. The connector 30 has a thin diameter section 31, a tapered section 32, and a thick diameter section 33. The thin diameter section 31 is a section that constitutes the tip end of the connector 30 and has a substantially constant outer diameter. The thick diameter section 33 is a section that constitutes the base end of the connector 30 and has a substantially constant outer diameter that is larger than the outer diameter of the thin diameter section 31. The tapered section 32 is provided between the thin diameter section 31 and the thick diameter section 33, and is a section whose outer diameter gradually increases from the boundary with the thin diameter section 31 to the boundary with the thick diameter section 33.

[0033] A branched portion 39 extending in a direction intersecting the central axis Ax is formed in the small diameter portion 31 of the connector 30. The inner cavity of the branched portion 39 communicates with the liquid supply lumen 18L formed in the tube 10. Therefore, liquid such as a contrast agent or saline can be supplied to the liquid supply lumen 18L via the branched portion 39.

[0034] The handle portion 40 is disposed on the base end side of the connector 30. The handle portion 40 has a shaft portion 41 and a handle main body portion 42. The shaft portion 41 is a substantially cylindrical member, and is connected to the base end of the connector 30. The inner cavity of the shaft portion 41 communicates with the inner cavity of the connector 30. A ring-shaped first finger receiving portion 43 is provided at the base end of the shaft portion 41.

[0035] The handle main body 42 is a substantially cylindrical member, and is attached to the shaft 41 so as to be slidable along the central axis Ax. The handle main body 42 is provided with a wire support portion 45 that protrudes into the inner cavity of the shaft 41, and the base end 22 of the knife wire 20 is supported (fixed) by the wire support portion 45. In addition, a pair of ring-shaped second finger receiving portions 44 are provided on the side surface of the handle main body 42. The handle main body 42 is an example of a support member.

[0036] The connector 30 and the handle portion 40 can be made of, for example, a resin material. Examples of resin materials that can be used to make the connector 30 and the handle portion 40 include polyurethane, polypropylene, hard polyvinyl chloride, polycarbonate resin, and acrylic resin.

[0037] (Method of operating the incision instrument 100) 5 and 6 are explanatory diagrams showing an example of a method of operating the incision instrument 100. As shown in FIG. 5, the surgeon, for example, inserts his thumb into the first finger receiving portion 43 and his index finger and middle finger into the second finger receiving portion 44, and rotates the handle main body 42 relative to the tube 10 (arrow AR2). Then, a rotational torque is generated in the base end 22 of the knife wire 20 supported by the wire support portion 45 of the handle main body 42, and the rotational torque is transmitted to the tip of the tube 10 fixed to the tip of the knife wire 20 via the knife wire 20. This causes the tube 10 to rotate around the central axis Ax, and as a result, the orientation of the exposed portion 20E of the knife wire 20 changes. The incision instrument 100 may have a locking mechanism that fixes the rotation angle of the handle main body 42 (i.e., the orientation of the exposed portion 20E of the knife wire 20).

[0038] 6, when the operator inserts the thumb through the first finger receiving portion 43, and the index finger and middle finger through the second finger receiving portion 44, and then pulls the index finger and middle finger toward the base end (arrow AR1), the handle main body 42 moves toward the base end along the outer circumferential surface of the shaft portion 41. Then, the base end 22 of the knife wire 20 supported by the wire support portion 45 of the handle main body 42 is pulled toward the base end, and tension is applied to the knife wire 20. This tension causes the tip of the tube 10 fixed to the tip of the knife wire 20 to bend in an arch shape. When the handle main body 42 is returned to the tip side, the tension of the knife wire 20 is relieved, and the tip of the tube 10 returns to a substantially straight shape.

[0039] Next, a procedure for incising the papilla using the incision instrument 100 in endoscopic papilla incision will be described. First, the surgeon inserts an endoscope into the duodenum, and delivers a guidewire (combination device) inserted under the endoscope from the opening of the papilla to the common bile duct. Next, the surgeon delivers the incision instrument 100 along the guidewire to the opening of the papilla. Specifically, after inserting the base end of the guidewire into the tip opening of the device lumen 16L of the incision instrument 100, the incision instrument 100 is advanced toward the tip side (distal side) until the tip of the incision instrument 100 reaches the opening of the papilla. At this time, the surgeon positions the handle main body 42 on the tip side (FIG. 1). This makes the tip of the tube 10 straight, and the tip of the tube 10 does not get caught on the papilla or the common bile duct when the incision instrument 100 is delivered.

[0040] Next, the surgeon rotates the handle main body 42 of the handle portion 40 relative to the tube 10 (Figure 5, arrow AR2), thereby rotating the tip of the tube 10 and setting the orientation of the exposed portion 20E of the knife wire 20 to an appropriate orientation for incising the nipple.

[0041] Thereafter, the surgeon applies tension to the knife wire 20 by sliding the handle main body 42 along the outer circumferential surface of the shaft 41 toward the base end (arrow AR1 in FIG. 6). This causes the tip of the tube 10 to bend into an arch shape, with the exposed portion 20E of the knife wire 20 pressed against the incision site. In this state, the surgeon applies a high-frequency current to the knife wire 20 from the high-frequency power source. This causes the exposed portion 20E of the knife wire 20 to incise a predetermined area of ​​the papilla into a predetermined shape.

[0042] (Effects of this embodiment) As described above, the incision instrument 100 of this embodiment includes the tube 10 having the knife wire lumen 17L, the knife wire 20 housed in the knife wire lumen 17L, and the handle main body 42 that rotatably supports the base end of the knife wire 20. Between the tip and base ends of the tube 10, the knife wire 20 has an exposed portion 20E that is exposed to the outside of the tube 10 via the tip side hole 12 and the base side hole 13 that communicate with the knife wire lumen 17L. The tube 10 has a first high stiffness portion 17 and a low stiffness portion 16 located on the tip side of the first high stiffness portion 17. The low stiffness portion 16 includes a portion formed from a material exhibiting an elastic modulus smaller than the elastic modulus of the material forming the first high stiffness portion 17.

[0043] Thus, in the incision instrument 100 of this embodiment, the tube 10 has a low rigidity portion 16 located further distal than the first high rigidity portion 17, and the low rigidity portion 16 includes a portion formed from a material exhibiting an elastic modulus smaller than that of the material forming the first high rigidity portion 17. Therefore, according to the incision instrument 100 of this embodiment, the presence of the low rigidity portion 16 can reduce the torsional rigidity of the portion of the tube 10 relatively distal, and the orientation of the exposed portion 20E of the knife wire 20 can be smoothly changed to a desired orientation by rotating the handle main body 42 while maintaining the inner and outer diameters of the tube 10 and the outer diameter of the knife wire 20.

[0044] In addition, in the incision instrument 100 of this embodiment, at least a portion of the low rigidity portion 16 is formed in the first portion P1, which is a portion where the exposed portion 20E of the knife wire 20 in the tube 10 is exposed. Therefore, according to the incision instrument 100 of this embodiment, the torsional rigidity of the first portion P1 where the exposed portion 20E of the knife wire 20 in the tube 10 is exposed can be effectively reduced, and the orientation of the exposed portion 20E of the knife wire 20 can be changed more smoothly by rotating the handle main body 42. In addition, the bending rigidity of the first portion P1 of the tube 10 can be effectively reduced, and the operability when bending the tube 10 and performing an incision with the exposed portion 20E of the knife wire 20 can be improved.

[0045] In the incision instrument 100 of this embodiment, the minimum diameter of the exposed portion 20E of the knife wire 20 is 0.15 mm or more and 0.30 mm or less. Therefore, according to the incision instrument 100 of this embodiment, it is possible to achieve both an improvement in the rotational torque transmissibility of the knife wire 20 and an improvement in the incision ability of the knife wire 20.

[0046] B. Second embodiment: 7 is a perspective view showing the external configuration of the tip of the incision instrument 100a of the second embodiment. In the following, among the configurations of the incision instrument 100a of the second embodiment, the same configurations as those of the incision instrument 100 of the first embodiment described above are designated by the same reference numerals and the description thereof will be omitted as appropriate.

[0047] The incision instrument 100a of the second embodiment differs from the incision instrument 100 of the first embodiment in the configuration of the tube 10. Specifically, in the incision instrument 100a of the second embodiment, the tube 10 has a second high rigidity portion 18 located on the distal side of the low rigidity portion 16 in addition to the low rigidity portion 16 and the first high rigidity portion 17. In this embodiment, the intermediate portion P5 including the first portion P1 in the tube 10 is the low rigidity portion 16, the base end portion P6 on the proximal side of the intermediate portion P5 is the first high rigidity portion 17, and the distal portion P4 on the distal side of the intermediate portion P5 is the second high rigidity portion 18. In this embodiment, the base end of the distal portion P4 is located on the distal side of the tip of the first portion P1.

[0048] The low rigidity portion 16 includes a portion formed from a material exhibiting a smaller elastic modulus than the material forming the second high rigidity portion 18. In this embodiment, the entire low rigidity portion 16 is formed from a material exhibiting a smaller elastic modulus than the material forming the second high rigidity portion 18. Such a configuration is realized, for example, by forming the second high rigidity portion 18 from a fluororesin and forming the low rigidity portion 16 from a nylon resin or a urethane resin. Alternatively, such a configuration is realized, for example, by forming the second high rigidity portion 18 from a nylon resin or a urethane resin and forming the low rigidity portion 16 from a material of a grade that is a nylon resin or a urethane resin and has a lower elastic modulus than the material forming the second high rigidity portion 18.

[0049] In the incision instrument 100a of the second embodiment, similarly to the incision instrument 100 of the first embodiment, the tube 10 has a low rigidity portion 16 located further distal than the first high rigidity portion 17, and the low rigidity portion 16 includes a portion formed from a material exhibiting an elastic modulus smaller than that of the material forming the first high rigidity portion 17. Therefore, the presence of the low rigidity portion 16 can reduce the torsional rigidity of the portion of the tube 10 relatively distal, and the orientation of the exposed portion 20E of the knife wire 20 can be smoothly changed to a desired orientation by rotating the handle main body 42 while maintaining the inner and outer diameters of the tube 10 and the outer diameter of the knife wire 20.

[0050] Furthermore, in the incision instrument 100a of the second embodiment, the tube 10 has a second high rigidity portion 18 located further distal than the low rigidity portion 16, and the low rigidity portion 16 includes a portion formed from a material exhibiting an elastic modulus smaller than that of the material forming the second high rigidity portion 18. Therefore, according to the incision instrument 100a of the second embodiment, the presence of the second high rigidity portion 18 makes it possible to relatively increase the torsional rigidity of the portion further distal than the low rigidity portion 16, improving the operability during delivery of the incision instrument 100a, while allowing the orientation of the exposed portion 20E of the knife wire 20 to be more smoothly changed to a desired orientation by rotating the handle main body 42.

[0051] C. Third embodiment: Fig. 8 is a perspective view showing the external configuration of the tip of the incision instrument 100b of the third embodiment, and Fig. 9 is an explanatory diagram showing the cross-sectional configuration (XY cross section) of the incision instrument 100b of the third embodiment. Fig. 9 shows the cross-sectional configuration of the incision instrument 100b at the position of the tip P2 of the tube 10. Note that the knife wire 20 is not shown in Fig. 9 (and Fig. 11 described later). In the following, among the configurations of the incision instrument 100b of the third embodiment, the same configurations as those of the incision instrument 100 of the first embodiment described above are denoted by the same reference numerals and their description will be omitted as appropriate.

[0052] The incision instrument 100b of the third embodiment differs from the incision instrument 100 of the first embodiment in that a notch 11 is formed in the tube 10. Specifically, the notch 11 is formed so as to extend along the outer surface of the tube 10. As shown in Fig. 9, the notch 11 is a cross-sectional loss portion in the tube 10. That is, in the cross section of the tube 10 at the portion where the notch 11 is formed (cross section shown in Fig. 9), a part of the outer side (outer periphery side) (area A1 in Fig. 9) is lost compared to the cross sections of other portions.

[0053] As shown in FIG. 8, in this embodiment, the entire cutout 11 is formed in the first portion P1 of the tube 10. The width W11 of the cutout 11 is larger than the diameter W16 of the device lumen 16L, the diameter W17 of the knife wire lumen 17L, and the diameter W18 of the liquid supply lumen 18L. However, the width W11 of the cutout 11 may be smaller than at least one of the diameter W16 of the device lumen 16L, the diameter W17 of the knife wire lumen 17L, and the diameter W18 of the liquid supply lumen 18L. The width W11 of the cutout 11 is the maximum size of the cutout 11 along a direction perpendicular to the central axis Ax of the tube 10.

[0054] The method for manufacturing the tube 10 having the notch 11 may be, for example, a method in which a tube 10 without the notch 11 is manufactured, and then a part of the tube 10 is scraped off to form the notch 11. Alternatively, the method may be a method in which the tube 10 having the notch 11 is directly molded using a mold or the like. In other words, the notch 11 is not limited to being formed by some kind of removal process, and may be a concave portion that is directly formed without going through a removal process.

[0055] In the incision instrument 100b of the third embodiment, similarly to the incision instrument 100 of the first embodiment, the tube 10 has a low rigidity portion 16 located further distal than the first high rigidity portion 17, and the low rigidity portion 16 includes a portion formed from a material exhibiting an elastic modulus smaller than that of the material forming the first high rigidity portion 17. Therefore, the presence of the low rigidity portion 16 can reduce the torsional rigidity of the portion of the tube 10 relatively distal, and the orientation of the exposed portion 20E of the knife wire 20 can be smoothly changed to a desired orientation by rotating the handle main body 42 while maintaining the inner and outer diameters of the tube 10 and the outer diameter of the knife wire 20.

[0056] Moreover, in the incision instrument 100b of the third embodiment, the tube 10 has a shape having a notch 11 extending along the outer surface of the tube 10 between the tip and base ends of the tube 10. Therefore, the presence of the notch 11 can effectively reduce the torsional rigidity of the tube 10, and the orientation of the exposed portion 20E of the knife wire 20 can be more smoothly changed to a desired orientation by rotating the handle main body 42.

[0057] D. Fourth embodiment: Fig. 10 is a perspective view showing the external configuration of the tip of the incision instrument 100c of the fourth embodiment, and Fig. 11 is an explanatory diagram showing the configuration of the cross section (XY cross section) of the incision instrument 100c of the fourth embodiment. Fig. 11 shows the cross section configuration of the incision instrument 100c at the position of the tip P2 of the tube 10. In the following, among the configurations of the incision instrument 100c of the fourth embodiment, the same configurations as those of the incision instrument 100 of the first embodiment described above are appropriately omitted by assigning the same reference numerals.

[0058] The incision instrument 100c of the fourth embodiment is different from the incision instrument 100 of the first embodiment in that a groove 15 is formed in the tube 10. Specifically, three grooves 15a, 15b, and 15c are formed in the tube 10. In this specification, the grooves 15a, 15b, 15c, and so on are also collectively referred to as grooves 15. Each groove 15 extends along the central axis Ax. As shown in FIG. 11, the groove 15 is a cross-sectional defect portion in the tube 10. That is, in the cross-section (cross-section shown in FIG. 11) of the portion in which the groove 15 is formed in the tube 10, a part (area A1, A2, and A3 in FIG. 11) on the outer side (outer circumferential side) is defective, compared with the cross-sections of the other portions. In this specification, groove 15 means a cross-sectional defect having a side surface, and notch 11 means a cross-sectional defect without a side surface, and the terms are used interchangeably; however, there is no essential difference between the two, and a groove may be called a notch, and a notch may be called a groove.

[0059] In this embodiment, the entirety of each of the three grooves 15a, 15b, and 15c is formed in the first portion P1 of the tube 10. As shown in Fig. 11, the widths W15a, W15b, and W15c of the three grooves 15a, 15b, and 15c are all larger than the diameter W16 of the device lumen 16L, the diameter W17 of the knife wire lumen 17L, and the diameter W18 of the liquid supply lumen 18L. However, at least one of the widths W15a, W15b, and W15c of the three grooves 15a, 15b, and 15c may be smaller than at least one of the diameter W16 of the device lumen 16L, the diameter W17 of the knife wire lumen 17L, and the diameter W18 of the liquid supply lumen 18L. The width W15 of the groove 15 is the maximum size of the groove 15 along a direction perpendicular to the extension direction of the groove 15 (the direction of the central axis Ax of the tube 10 in this embodiment).

[0060] In the incision instrument 100c of the fourth embodiment, similarly to the incision instrument 100 of the first embodiment, the tube 10 has a low rigidity portion 16 located further distal than the first high rigidity portion 17, and the low rigidity portion 16 includes a portion formed from a material exhibiting an elastic modulus smaller than that of the material forming the first high rigidity portion 17. Therefore, the presence of the low rigidity portion 16 can reduce the torsional rigidity of the portion of the tube 10 relatively distal, and the orientation of the exposed portion 20E of the knife wire 20 can be smoothly changed to a desired orientation by rotating the handle main body 42 while maintaining the inner and outer diameters of the tube 10 and the outer diameter of the knife wire 20.

[0061] Moreover, in the incision instrument 100c of the fourth embodiment, the tube 10 has a groove 15 extending along the outer surface of the tube 10 between the tip and base ends of the tube 10. Therefore, the presence of the groove 15 can effectively reduce the torsional rigidity of the tube 10, and the orientation of the exposed portion 20E of the knife wire 20 can be more smoothly changed to a desired orientation by rotating the handle main body 42.

[0062] E. Variations: The technology disclosed in this specification is not limited to the above-described embodiments, and can be modified in various forms without departing from the spirit of the invention. For example, the following modifications are also possible.

[0063] The configuration of the incision instrument 100 in the above embodiment is merely an example, and various modifications are possible. For example, in the above first embodiment, the boundary between the low-rigidity portion 16 and the first high-rigidity portion 17 in the tube 10 is located on the proximal side of the proximal end of the first portion P1, but the boundary may be located on the distal side of the proximal end of the first portion P1, or may be located on the distal side of the distal end of the first portion P1. Similarly, in the above second embodiment, the boundary between the low-rigidity portion 16 and the second high-rigidity portion 18 in the tube 10 is located on the distal side of the distal end of the first portion P1, but the boundary may be located on the proximal side of the distal end of the first portion P1, or may be located on the proximal side of the proximal end of the first portion P1.

[0064] In the first embodiment described above, the entire low rigidity portion 16 is formed from a material exhibiting a smaller elastic modulus than the material forming the first high rigidity portion 17, but a part of the low rigidity portion 16 may be formed from a material exhibiting a smaller elastic modulus than the material forming the first high rigidity portion 17. Similarly, in the second embodiment described above, the entire low rigidity portion 16 is formed from a material exhibiting a smaller elastic modulus than the material forming the second high rigidity portion 18, but a part of the low rigidity portion 16 may be formed from a material exhibiting a smaller elastic modulus than the material forming the second high rigidity portion 18.

[0065] In the above embodiment, so long as the tube 10 has the first high rigidity portion 17 and the low rigidity portion 16 located closer to the tip than the first high rigidity portion 17, the tube 10 may have other high rigidity portions or low rigidity portions.

[0066] In the above embodiment, the shape of the notches 11 or grooves 15 formed in the tube 10 can be changed arbitrarily. For example, the grooves 15 may be spiral stripes, diagonal cross stripes, or ripple stripes. Also, in the above embodiment, the number of notches 11 or grooves 15 formed in the tube 10 can be changed arbitrarily. Also, in the above embodiment, the notches 11 and grooves 15 may be formed in the tube 10.

[0067] In the above embodiment, the knife wire lumen 17L, the device lumen 16L, and the liquid supply lumen 18L are formed in the tube 10, but the device lumen 16L and / or the liquid supply lumen 18L may not be formed.

[0068] In the above embodiment, the exposed portion 20E of the knife wire 20 is always exposed to the outside of the tube 10, but it is sufficient that the exposed portion 20E of the knife wire 20 is exposed to the outside of the tube 10 at least when the tube 10 is in a predetermined position (e.g., a position in which the tube 10 is greatly curved), and it is not necessary for the exposed portion 20E to be exposed to the outside at all times.

[0069] The technology disclosed in this specification has been described above based on the embodiments and modifications, but the above-mentioned embodiments and modifications are intended to facilitate understanding of the technology disclosed in this specification and do not limit the technology disclosed in this specification. The technology disclosed in this specification may be modified or improved without departing from the spirit thereof, and the technology disclosed in this specification includes its equivalents. Furthermore, if a technical feature is not described as essential in this specification, it may be deleted as appropriate. [Explanation of symbols]

[0070] 10: Tube 11: Notch 12: Tip side hole 13: Base side hole 14: Marker 15: Groove 16: Low rigidity section 16L: Device lumen 17: First high rigidity section 17L: Knife wire lumen 18: Second high rigidity section 18L: Fluid delivery lumen 19: Branching section 20: Knife wire 20E: Exposed section 21: Tip section 22: Base end section 30: Connector 31: Thin diameter section 32: Tapered section 33: Thick diameter section 39: Branching section 40: Handle section 41: Shaft section 42: Handle body section 43: First finger receiving section 44: Second finger receiving section 45: Wire support section 80: Fixing member 100: Cutting instrument Ax: Central axis P1: First section

Claims

1. It is an incision instrument, A tube having lumens, The knife wire housed in the aforementioned lumen, A support member that rotatably supports the base end of the knife wire, Equipped with, The knife wire has an exposed portion between the tip and base end of the tube that is exposed to the outside of the tube through a hole that leads to the lumen when the tube is in a predetermined position. The tube has a first high-rigidity portion and a low-rigidity portion located closer to the tip than the first high-rigidity portion. The incision instrument wherein the low-rigidity portion includes a portion formed from a material exhibiting an elastic modulus smaller than that of the material forming the first high-rigidity portion.

2. The cutting instrument according to claim 1, The tube further has a second high-rigidity portion located closer to the tip than the low-rigidity portion, The incision instrument wherein the low-rigidity portion includes a portion formed from a material exhibiting an elastic modulus smaller than that of the material forming the second high-rigidity portion.

3. An incision instrument according to claim 1 or claim 2, A cutting instrument in which at least a portion of the low-rigidity part is formed in a first portion of the tube, which is the portion where the exposed part of the knife wire is exposed.

4. An incision instrument according to claim 1 or claim 2, An incision instrument in which the minimum diameter of the exposed portion of the knife wire is 0.15 mm or more and 0.30 mm or less.

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