Endoscopic introducer

Abstract

To provide an endoscopic introducer with excellent operability. [Solution] The endoscopic introducer 10 according to the present invention comprises a synthetic resin composition to which a contrast-enhancing material having radiopaqueness to X-rays has been added, and includes a sheath tube 30 that is inserted into the body via an endoscope, and a hollow sheath hub 40 connected to the proximal end of the sheath tube 30. The sheath hub 40 is configured to have a sheath hub tip portion 41 connected to the proximal end of the sheath tube 30, a side injection tube connection portion 45 that branches off from the lumen of the sheath hub 40 and opens laterally, and a sheath hub base portion 42 that is sealed by a valve body 43. The valve body 43 is made of an elastic material, and a sealing hole 43a is formed in the center of the valve body 43.

Description

Technical Field

[0001] The present invention relates to an introducer for an endoscope that is inserted into a body via an endoscope, and particularly relates to an introducer for an endoscope that is inserted into a luminal organ such as a bile duct or a pancreatic duct through a treatment instrument insertion channel of an endoscope.

Background Art

[0002] ERCP (Endoscopic Retrograde Cholangiopancreatography) is known as a procedure related to examination and treatment of bile ducts and pancreatic ducts. In ERCP, an oral endoscope is advanced to the duodenal papilla, a thin tube is inserted from the duodenal papilla into the bile duct or pancreatic duct through the treatment instrument insertion channel of the endoscope, and a contrast medium is injected into the bile duct or pancreatic duct via the tube.

[0003] Patent Document 1 below discloses a biliary catheter that includes a dual lumen formed with a first lumen for inserting a spring wire guide and a second lumen for delivering a contrast medium, and a branch connector connected to the proximal end portion. A threaded outer surface is formed at the base end portion of the branch connector, which is configured to be detachably connectable with a locking mechanism for positioning the spring wire guide and a locking mechanism for introducing accessories such as a basket and a camera into the body.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of Invention

Problems to be Solved by the Invention

[0005] However, the technology disclosed in Patent Document 1 has a problem in that when using various treatment tools, it is necessary to attach and detach the locking mechanisms of the various treatment tools to the base end of the branch connector by screwing them in, which is cumbersome and results in poor operability.

[0006] This invention has been made in view of the above problems, and aims to provide an endoscopic introducer with excellent operability. [Means for solving the problem]

[0007] To achieve the above objective, the endoscopic introducer according to the present invention comprises a synthetic resin composition to which a contrast-enhanced material having radiopaqueness to X-rays has been added, and includes a sheath tube that is inserted into the body via an endoscope, and a hollow sheath hub connected to the proximal end of the sheath tube, wherein the sheath hub is configured to have a sheath hub tip connected to the proximal end of the sheath tube, a side injection tube connection portion that branches off from the lumen of the sheath hub and opens laterally, and a sheath hub base end sealed by a valve body, wherein the valve body is made of an elastic material and a sealing hole is formed in the center of the valve body.

[0008] With the above configuration, contrast agent can be injected into the body through the side injection tube connection, and the long insertion portion of various treatment instruments such as biopsy forceps can be inserted into the body by passing it through the sealing hole of the valve body provided at the base end of the sheath hub. The inner circumferential surface of the sealing hole of the valve body, which is made of an elastic material, adheres tightly to the outer circumferential surface of the long insertion portion of various treatment instruments that pass through the sealing hole of the valve body due to its elastic force, thereby maintaining the airtight seal of the lumen of the sheath hub. As a result, locking operations such as screw fastening are unnecessary, and operability can be improved.

[0009] Furthermore, with the above configuration, since the sheath tube contains a material that is radiopaque to X-rays, the position of the sheath tube can be confirmed under X-ray fluoroscopy, allowing for safe and reliable positioning of the sheath tube.

[0010] In the endoscopic introducer according to the present invention, a blade layer may be embedded in the sheath tube.

[0011] According to the above configuration, the strength of the sheath tube can be improved, and user input can be appropriately transmitted to improve operability, such as advancing and retracting movements and positioning operations within the body.

[0012] The introducer for endoscopes according to the present invention comprises a dilator having a dilator tube that can be inserted into the sheath tube by passing through the sealing hole of the valve body, and a dilator hub that can be attached to the base end of the sheath hub, wherein the distal end of the dilator tube is tapered, and the distal end of the dilator tube may be exposed from the tip opening of the sheath tube when the dilator hub is attached to the base end of the sheath hub.

[0013] With the above configuration, a dilator tube with a tapered distal end can be inserted into the body while exposed from the sheath tube, allowing the sheath tube to be safely and smoothly inserted into narrow tubular organs such as the bile duct and pancreatic duct. [Brief explanation of the drawing]

[0014] [Figure 1] This is a plan view showing an endoscopic introducer in an embodiment of the present invention. [Figure 2] Figure 1 shows a cross-sectional view of the sheath tube along line AA. [Figure 3] Figure 1 is a cross-sectional view showing the vicinity of the sheath hub of the sheath that constitutes the endoscopic introducer. [Figure 4] This is a plan view showing a dilator attached to the sheath constituting an endoscopic introducer in an embodiment of the present invention. [Figure 5] This is a partial cross-sectional view of Figure 4. [Figure 6]This is a plan view showing a biopsy forceps inserted into the sheath constituting an endoscopic introducer in an embodiment of the present invention. [Figure 7] This is a partial cross-sectional view of Figure 6. [Figure 8] This is a schematic diagram illustrating the method of using the endoscopic introducer in an embodiment of the present invention, and shows the first state. [Figure 9] This is a schematic diagram illustrating the method of using the endoscopic introducer in an embodiment of the present invention, and shows the second state. [Figure 10] This is a schematic diagram illustrating the method of using the endoscopic introducer in an embodiment of the present invention, and shows the third state. [Modes for carrying out the invention]

[0015] Embodiments of the present invention will be described in detail below with reference to the drawings. In this specification, the side of the endoscopic introducer used by the user (outside the patient's body) will be referred to as the proximal side, and the side inside the patient's body will be referred to as the distal side. The drawings referenced in this specification are not necessarily to an accurate scale with respect to the actual dimensions, and some parts have been exaggerated or simplified in order to schematically illustrate the configuration of the present invention.

[0016] The following describes the endoscopic introducer in this embodiment. The endoscopic introducer in this embodiment is an instrument that, in ERCP-related procedures, is inserted into the bile duct or pancreatic duct through the instrument insertion channel (forceps channel) of the endoscope located near the duodenal papilla, injects contrast agent into the bile duct or pancreatic duct, and, if necessary, guides various instruments equipped with a long insertion section to the target site. The instruments guided to the target site by the endoscopic introducer in this embodiment are not particularly limited, and for example, the long insertion sections of various instruments such as biopsy forceps for collecting tissue from the target site, basket devices for removing gallstones, hemostatic devices, ligation devices, stent delivery devices, and high-frequency knife devices can be guided to the target site in the bile duct or pancreatic duct.

[0017] Figure 1 is a plan view showing the introducer for endoscope 10 in the present embodiment. Figure 2 is a cross-sectional view of the sheath tube 30 taken along the line A-A shown in Figure 1. Figure 3 is a cross-sectional view in the vicinity of the sheath hub 40 of the sheath 20 constituting the introducer for endoscope 10 of Figure 1.

[0018] As shown in Figure 1, the introducer for endoscope 10 is generally configured to include a sheath 20 and a dilator 50.

[0019] The sheath 20 (left side in Figure 1) constituting the introducer for endoscope 10 has a sheath tube 30 and a sheath hub 40.

[0020] The sheath tube 30 is an elongated tubular member, and has flexibility to bend flexibly. As shown in Figure 3, the sheath tube 30 is formed with a lumen (tube inner cavity 30s) along the axial direction. The tube inner cavity 30s is open at the distal end portion (tube distal end portion 30a) and the proximal end portion (tube proximal end portion 30b) of the sheath tube 30.

[0021] The sheath tube 30 is inserted into the body endoscopically. The outer diameter of the sheath tube 30 is set to a size that allows smooth passage through the treatment instrument insertion channel of the endoscope, and is, for example, about 1.0 to 4.0 mm. The wall thickness of the sheath tube 30 is about 0.05 to 0.5 mm. The length of the sheath tube 30 may be a length that allows reaching the target site in the body from the sheath hub 40 disposed outside the body, and is, for example, about 500 to 3000 mm. The tube distal end portion 30a may be formed in a tapered shape that narrows toward the distal side (tip side) in order to improve the insertability into the bile duct or pancreatic duct. In addition, by slightly reducing the inner diameter of the tube distal end portion 30a, the adhesion to the outer peripheral surface of the dilator tube 60 may be improved when the dilator 50 is attached to the sheath 20.

[0022] The sheath tube 30 is composed of a contrast-enhanced material that is radiopaque to X-rays. The contrast-enhanced material is not particularly limited as long as it is contrast-enhanced under X-ray fluoroscopy, and can be, for example, barium sulfate, bismuth subcarbonate, tungsten, barium oxide, barium carbonate, barium phosphate, calcium phosphate, titanium oxide, bismuth oxide, bismuth sulfide, bismuth titanate, molybdenum oxide, tungsten trioxide, ammonium iron citrate, iron sulfate, ferric pyrophosphate, etc., and it is particularly preferable to use barium sulfate, bismuth subcarbonate, or tungsten.

[0023] The sheath tube 30 is formed using a synthetic resin composition in which a contrast-enhancing material is added to a synthetic resin. The amount of contrast-enhancing material added is not particularly limited, but for example, it can be 10 to 60% by mass of the total mass of the synthetic resin and the contrast-enhancing material, and is preferably 20 to 50% by mass. In order to more uniformly disperse the particles of the contrast-enhancing material in the synthetic resin composition, the surface of the particles of the contrast-enhancing material may be treated with a coupling agent such as a silane coupling agent, an aluminum coupling agent, or a titanium coupling agent.

[0024] The sheath tube 30 may be made of a synthetic resin composition to which a contrast-enhancing material is added along its entire longitudinal direction. Alternatively, only the distal end of the sheath tube 30 inserted into the bile duct or pancreatic duct may be made of a synthetic resin composition to which a contrast-enhancing material is added. This allows the position of the sheath tube 30 placed in the bile duct or pancreatic duct to be accurately confirmed under X-ray fluoroscopy, thereby preventing insertion into the wrong position and tissue damage, and improving safety.

[0025] Furthermore, a contrast marker 35 may be attached near the distal end of the sheath tube 30 to improve the accuracy of positioning the sheath tube 30 under X-ray fluoroscopy. The contrast marker 35 can be formed from, for example, metallic materials such as gold, platinum, or tungsten, or polymers blended with barium sulfate or bismuth oxide.

[0026] In this embodiment, the sheath tube 30 can be composed of a single-lumen multilayer tube having an inner layer 31 and an outer layer 32, as shown in Figure 2, for example. A tube lumen 30s is formed inside the inner layer 31. In addition, a blade layer 33 made of a mesh-like reinforcing wire (for example, a metal wire such as stainless steel) may be embedded to ensure the strength of the sheath tube 30. In this embodiment, the blade layer 33 is embedded between the inner layer 31 and the outer layer 32, but the blade layer 33 may be embedded in the outer layer 32 or in the inner layer 31.

[0027] The material for the inner layer 31 is not particularly limited, but for example, fluororesins such as polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-ethylene copolymer (ETFE), and polyvinylidene fluoride (PVDF) can be used. The material for the outer layer 32 is not particularly limited, but for example, polyvinyl chloride resin, urethane resin such as polyurethane, polyurethane elastomer, polyethylene, polypropylene, polyolefin resin such as ethylene-propylene copolymer, polyolefin elastomer, polyamide resin, polyamide elastomer, fluororesins such as polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-ethylene copolymer (ETFE), and polyvinylidene fluoride (PVDF), and synthetic resins such as ethylene-vinyl acetate copolymer can be used, and synthetic resin compositions in which the above-mentioned contrast-enhancing material is added to these synthetic resins can be used.

[0028] In this way, the sheath tube 30 is constructed using a multilayer tube having an inner layer 31 in addition to an outer layer 32 made of a synthetic resin composition to which a contrast-enhancing material has been added, and by further providing a blade layer 33, the strength (especially kink resistance) of the sheath tube 30 can be improved. However, the sheath tube 30 is not limited to the configuration shown in Figure 2, and may be a single-layer tube having only an outer layer 32 made of a synthetic resin composition to which a contrast-enhancing material has been added without an inner layer 31, or a configuration in which the blade layer 33 is not embedded.

[0029] As shown in Figure 3, the tube base end 30b is connected to the sheath hub 40. The method of connecting the sheath tube 30 and the sheath hub 40 is not particularly limited, but they may be joined by, for example, tube crimping, bonding, or fusion. Alternatively, the sheath tube 30 and the sheath hub 40 may be integrally constructed.

[0030] The sheath hub 40 is a hollow component that constitutes the sheath body. The material used to make up the sheath hub 40 is not particularly limited, and for example, ABS resin, polyvinyl chloride resin, polyacetal resin, polyacrylonitrile resin, polyamide resin, polyethylene resin, polycarbonate resin, or polypropylene resin can be used.

[0031] The distal end (sheath hub tip 41) and proximal end (sheath hub base 42) of the sheath hub 40 have a sheath hub tip opening 41a and a sheath hub base opening 42a, respectively, which open the lumen of the sheath hub 40 (sheath hub lumen 40s) to the outside. The sheath hub tip opening 41a and the sheath hub base opening 42a are located on the axis of the sheath hub 40 and are arranged to face each other in the axial direction (longitudinal direction).

[0032] A sheath tube 30 is inserted into and fixed at the tip opening 41a of the sheath hub, and the lumen 30s of the sheath tube 30 is in communication with the lumen 40s of the sheath hub, which is formed inside the sheath hub 40.

[0033] As shown in Figure 3, a valve body 43 is installed inside the sheath hub 40 near the base end opening 42a of the sheath hub so as to close the base end opening 42a of the sheath hub. A sealing hole 43a is formed in the center of the valve body 43. An elastic force acts on the valve body 43 to close the sealing hole 43a, and the inner surface of the sealing hole 43a becomes tightly sealed. Furthermore, when a long insertion portion constituting various treatment instruments (e.g., biopsy forceps) is placed in the sealing hole 43a, the inner surface of the sealing hole 43a becomes tightly sealed with the outer surface of the long insertion portion. In this way, the valve body 43 is configured to maintain the airtightness (airtightness and liquidtightness) of the lumen 40s of the sheath hub while allowing the dilator tube 60 and the long insertion portion constituting various treatment instruments to be inserted into the inside of the sheath hub 40 through the sealing hole 43a. The material of the valve body 43 is not particularly limited, but it is preferably elastic and is made of, for example, natural rubber, butyl rubber, ethylene-propylene rubber, polybutadiene rubber, polyisoprene rubber, silicone rubber, polyurethane rubber, fluororubber, or other synthetic rubber, preferably silicone rubber.

[0034] The sheath hub base end 42 constitutes the proximal end (base end) of the sheath 20 and is designed to accommodate the dilator 50. The sheath hub base end 42 is provided with a locking mechanism for securing the dilator 50 attached to the sheath 20. The structure of the locking mechanism is not particularly limited, but for example, the outer circumferential surface of the sheath hub 40 and the inner circumferential surface of the dilator hub 70 may have a screw-in or threaded structure, allowing the dilator hub 70 to be fixed by fitting it into the sheath hub base end 42 and rotating it. In this case, the locking mechanism is composed of an engaging projection 44, which engages with an inclined projection 73 (see Figure 5, described later) formed on the inner circumferential surface of the dilator hub 70 to secure them together.

[0035] A side-fill tube connection portion 45 is provided on the side of the sheath hub 40, formed such that a part of the housing of the sheath hub 40 protrudes laterally. As shown in Figure 3, a through hole 45a is formed in the side-fill tube connection portion 45, extending through in the direction of protrusion (later). One end of the through hole 45a in the side-fill tube connection portion 45 opens into the lumen 40s of the sheath hub, and the other end opens to the outside of the sheath hub 40.

[0036] An opening formed at the other end of the side injection tube connector 45 is connected to one end of the side injection tube 46, allowing contrast agent to be introduced through the side injection tube 46. The contrast agent introduced from the side injection tube 46 is injected into the bile duct or pancreatic duct via the sheath hub 40 and the sheath tube 30. The method of connecting the side injection tube connector 45 and the side injection tube 46 is not particularly limited, but they may be joined by, for example, tube crimping, bonding, or fusion.

[0037] The side injection tube 46 can be made of, for example, a synthetic resin tube. The synthetic resin used to make up the side injection tube 46 is not particularly limited, but for example, polyurethane resin, polyvinyl chloride resin, silicone resin, polyethylene resin, polypropylene resin, and other synthetic resins can be used. The outer diameter and inner diameter of the side injection tube 46 are not particularly limited as long as it can be attached to the side injection tube connection part 45, and the length of the side injection tube 46 can also be set as appropriate. In Figure 1, a three-way stopcock 47 that can open and close the lumen of the side injection tube 46 is attached to the other end of the side injection tube 46. The side injection tube 46 is not particularly limited as long as it can be configured to accept contrast agent, and for example, a syringe containing contrast agent may be directly attached to the side injection tube connection part 45.

[0038] The dilator 50 (right side in Figure 1), which constitutes the endoscopic introducer 10, has a dilator tube 60 and a dilator hub 70. The material constituting the dilator tube 60 is not particularly limited, but synthetic resins such as polyvinyl chloride resin, polyurethane and other urethane resins, polyurethane elastomers, polyethylene, polypropylene, polyolefin resins such as ethylene-propylene copolymer, polyolefin elastomers, polyamide resins, polyamide elastomers, polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-ethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), and ethylene-vinyl acetate copolymer can be used. Synthetic resin compositions in which the above-mentioned contrast-enhancing material is added to these synthetic resins can be used.

[0039] The dilator tube 60 is a long, tubular member that is flexible and can be bent easily, while also being rigid in the axial direction. The dilator tube 60 can be inserted into the lumen 30s of the sheath tube 30, and the outer diameter of the dilator tube 60 is set to be smaller than the inner diameter of the sheath tube 30. The lumen of the dilator tube 60 also serves as a guide wire insertion hole for inserting a guide wire, and the inner diameter of the dilator tube 60 is set to be approximately the same as or slightly larger than the outer diameter of the guide wire, for example, 0.5 to 2.0 mm. The length of the dilator tube 60 is longer than the length of the sheath tube 30, so that when the dilator 50 is attached to the sheath 20, the distal end of the dilator tube 60 is exposed for a predetermined length from the tip 30a of the sheath tube 30. The distal end of the dilator tube 60 has a tapered section 60a that narrows towards the distal end in order to improve the ease of inserting the sheath tube 30 into the bile duct or pancreatic duct.

[0040] A dilator hub 70 is connected to the proximal end (base end) of the dilator tube 60, forming the base of the dilator. The dilator hub 70 is formed in a cylindrical shape. The dilator tube 60 and the dilator hub 70 may be joined by adhesive or fusion, or they may be integrally formed.

[0041] The lumen of the dilator tube 60 and the lumen of the dilator hub 70 are in communication, forming the lumen of the dilator 50 (the dilator lumen 50s in Figure 5, which will be described later). The dilator lumen 50s is opened at the dilator tip opening 50a formed at the distal end of the dilator tube 60 and the dilator base opening 50b formed at the proximal end of the dilator hub 70.

[0042] The dilator hub 70 is configured to be detachably attached to the base end 42 of the sheath hub, and is provided with a locking portion that allows it to be attached to the base end 42 of the sheath hub. The structure of the locking portion is not particularly limited as long as it fits the base end 42 of the sheath hub. Here, as the locking portion, an inclined projection 73 (see Figure 5, described later) that can engage with an engaging projection 44 provided on the base end 42 of the sheath hub is formed on the inner circumferential surface of the dilator hub 70. By fitting the distal end of the dilator hub 70 onto the base end 42 of the sheath hub and rotating it, the engaging projection 44 of the base end 42 of the sheath hub and the inclined projection 73 of the dilator hub 70 can engage with each other and be connected. The material constituting the dilator hub 70 is not particularly limited, and for example, ABS resin, polyvinyl chloride resin, polyacetal resin, polyacrylonitrile resin, polyamide resin, polyethylene resin, polycarbonate resin, or polypropylene resin can be used.

[0043] The state in which the dilator 50 is attached to the sheath 20 will be described with reference to Figures 4 and 5. Figure 4 is a plan view showing the state in which the dilator 50 is attached to the sheath 20 which constitutes the endoscopic introducer 10 in this embodiment, and Figure 5 is a partial cross-sectional view of Figure 4. In Figure 5, the sheath hub 40 and the dilator hub 70 are shown in cross-section.

[0044] The dilator hub 70 of the dilator 50 can be attached to the base end portion 42 of the sheath hub. As shown in Figure 5, the distal end face (tip face) of the dilator hub 70 is provided with a recess 71 that forms a recess for inserting the base end portion 42 of the sheath hub, and an inclined protrusion 73 is provided on the side circumferential surface of the recess 71.

[0045] The dilator hub 70 can be attached to the sheath hub base end 42 by the following procedure. First, the dilator tube 60 is pushed in while inserting its distal end into the sealing hole 43a of the valve body 43. The pushed-in dilator tube 60 passes from the lumen 40s of the sheath hub through the tube base end 30b and into the lumen 30s. The dilator tube 60 is pushed in further to fit the recess 71 provided at the distal end of the dilator hub 70 into the sheath hub base end 42.

[0046] The dilator hub 70 is firmly pressed onto the base end 42 of the sheath hub, and with the dilator hub 70 placed over the base end 42 of the sheath hub, the dilator hub 70 fitted onto the base end 42 of the sheath hub is rotated to engage the engaging projection 44 provided on the base end 42 of the sheath hub with the inclined projection 73 provided on the dilator hub 70. As a result, the dilator hub 70 is detachably fixed to the base end 42 of the sheath hub, as shown in Figures 4 and 5. When the dilator hub 70 is fixed to the base end 42 of the sheath hub, the tapered portion 60a formed at the distal end of the dilator tube 60 is exposed from the tube tip 30a of the sheath tube 30.

[0047] When the dilator hub 70 is attached to the base end portion 42 of the sheath hub, the dilator tube 60 is inserted into the sealing hole 43a of the valve body 43. An elastic force acts on the valve body 43 to close the sealing hole 43a, and the outer surface of the dilator tube 60 and the inner surface of the sealing hole 43a of the valve body 43 come into close contact, ensuring the airtightness of the lumen 40s of the sheath hub.

[0048] Furthermore, the dilator 50 can be removed from the sheath 20 by releasing the fixation of the dilator hub 70 to the sheath hub base end 42. When the dilator 50 is removed from the sheath 20, the inner circumferential surface of the sealing hole 43a becomes tightly sealed due to the elastic force acting on the sealing hole 43a. This ensures that the sealing hole 43a is closed and the lumen 40s of the sheath hub is sealed without requiring the user to perform a locking operation such as screwing.

[0049] Referring to Figures 6 and 7, the state in which a treatment instrument equipped with a long insertion section is attached to the sheath 20 will be described. Here, as a treatment instrument equipped with a long insertion section, a biopsy forceps 300 in which a forceps section 302 is provided at the distal end of the long insertion section 301 is given as an example, but various treatment instruments can be used. Figure 6 is a plan view showing the state in which the biopsy forceps 300 is inserted into the sheath 20 constituting the endoscopic introducer 10 in this embodiment, and Figure 7 is a partial cross-sectional view of Figure 6. In Figure 7, the sheath hub 40 is shown in cross-section.

[0050] In this embodiment, the endoscopic introducer 10 uses the sheath tube 30 as a guide tube to guide the forceps portion 302 of the biopsy forceps 300 to the target site inside the patient's body.

[0051] When inserting the biopsy forceps 300 into the body, first, the distal end of the long insertion portion 301 of the biopsy forceps 300 is inserted into the sealing hole 43a of the valve body 43, while pushing the long insertion portion 301 in. The pushed-in long insertion portion 301 passes from the lumen 40s of the sheath hub through the proximal end 30b of the tube and is inserted into the lumen 30s of the tube. By pushing the long insertion portion 301 in further, the forceps portion 302 provided at the distal end of the long insertion portion 301 can be exposed from the tip 30a of the sheath tube 30. In this state, tissue from inside the body can be collected by operating the control unit (not shown) connected to the proximal side of the long insertion portion 301 of the biopsy forceps 300 to open and close the forceps portion 302.

[0052] When the biopsy forceps 300 is inserted into the body through the sealing hole 43a of the valve body 43, the valve body 43 elastically deforms, and the long insertion portion 301 of the biopsy forceps 300 is positioned inside the sealing hole 43a of the valve body 43. An elastic force acts on the valve body 43 to close the sealing hole 43a, and the outer surface of the long insertion portion 301 and the inner surface of the sealing hole 43a of the valve body 43 come into close contact, ensuring the airtightness of the sheath hub lumen 40s.

[0053] Furthermore, the biopsy forceps 300 can be removed from the sheath 20 by withdrawing it from the sheath 20. When the biopsy forceps 300 is removed from the sheath 20, the elastic force acting on the sealing hole 43a causes the inner surface of the sealing hole 43a to be in close contact. This ensures that the sealing hole 43a is closed and the lumen 40s of the sheath hub is sealed without requiring the user to perform any locking operation such as screwing. Moreover, various instruments can be inserted and removed in the same manner, and various instruments can be easily replaced as needed.

[0054] Next, the method of using the endoscopic introducer 10 in this embodiment will be described with reference to Figures 8 to 10. Figures 8 to 10 are schematic diagrams illustrating the method of using the endoscopic introducer 10 in this embodiment, and show the first to third states. Here, we will describe a method in which, after performing cholangiography by ERCP using the endoscopic introducer 10 shown in Figure 1, tissue is collected from the target site T in the bile duct 103 using biopsy forceps 300. Figures 8 to 10 schematically illustrate the duodenum 101, duodenal papilla 102, and bile duct 103, etc., inside the patient's body. Here, as an example, we will describe the case where the target site T is located in the hepatic hilum 104.

[0055] First, the sheath 20 and dilator 50 that constitute the endoscopic introducer 10 are prepared. The distal end (tip) of the dilator tube 60 is inserted into the sheath hub base end 42 of the sheath hub 40, and the dilator hub 70 is fixed to the sheath hub base end 42 to integrate the sheath 20 and the dilator 50. At this time, the distal end of the dilator tube 60 inserted from the sheath hub base end 42 passes through the sealing hole 43a of the valve body 43, and the tapered portion 60a of the dilator tube 60 is exposed from the tube tip 30a of the sheath tube 30. Due to its elastic force, the inner surface of the sealing hole 43a of the valve body 43 adheres tightly to the outer surface of the dilator tube 60, and the airtightness of the lumen 40s of the sheath hub is maintained without the need for locking operations such as screw fastening.

[0056] Next, while observing the camera image of the endoscope 200, the endoscope 200 is inserted into the duodenum 101 from the patient's oral cavity through the esophagus and stomach, and the distal end of the endoscope 200 is rotated as appropriate so that the opening of the instrument insertion channel of the endoscope 200 is directed toward the duodenal papilla 102. Then, the guidewire 201 is inserted through the instrument insertion channel of the endoscope 200 and inserted into the bile duct 103 through the opening of the instrument insertion channel, and the guidewire 201 is advanced until its distal end is inserted into the bile duct 103.

[0057] Next, the proximal end of the guidewire 201 is inserted into the dilator tip opening 50a and led out from the dilator base opening 50b, and the guidewire 201 is inserted into the dilator lumen 50s. The sheath tube 30 of the endoscopic introducer 10 with the dilator 50 attached is inserted into the instrument insertion channel of the endoscope 200, and the sheath tube 30 is advanced along the guidewire 201. Then, the sheath tube 30 with the dilator 50 attached is led out from the instrument insertion channel of the endoscope 200 and inserted into the bile duct 103, and the sheath tube 30 is advanced under X-ray fluoroscopy to position the tube tip 30a near the target site T in the bile duct 103. The sheath tube 30 contains a contrast-enhanced material that is radiopaque to X-rays, and the position of the sheath tube 30 can be confirmed under X-ray fluoroscopy. This allows the tube tip 30a to be safely and reliably positioned near the target site T within the bile duct 103 while advancing and retracting the sheath tube 30 under X-ray fluoroscopy. The state at this time (first state) is shown in Figure 8.

[0058] Next, the fixation of the dilator hub 70 to the proximal end 42 of the sheath hub is released, and the dilator 50 is removed from the sheath 20 while the tip 30a of the sheath tube 30 remains inside the bile duct 103. When the dilator 50 is removed from the sheath 20, the distal end of the dilator tube 60 passes through the sealing hole 43a of the valve body 43 of the sheath hub 40, and the dilator 50 is removed from the body. Once the dilator 50 is removed, the sealing hole 43a is closed by the elastic force of the valve body 43, and the airtightness of the lumen 40s of the sheath hub is maintained without the need for locking operations such as screw fastening. This state (second state) is shown in Figure 9.

[0059] Next, the contrast agent is introduced through the side injection tube 46. The contrast agent is injected into the bile duct 103 via the lumen 30s of the sheath tube 30, thereby enabling the acquisition of a clear contrast-enhanced image of the bile duct 103 under X-ray fluoroscopy. Furthermore, the position of the tube tip 30a can be finely adjusted while confirming the morphology of the bile duct 103, which has become clearer after the injection of the contrast agent.

[0060] Furthermore, various procedures can be performed while confirming the contrast-enhanced image of the bile duct 103. For example, when collecting tissue from a target site T within the bile duct 103, the biopsy forceps 300 are inserted into the bile duct 103. Specifically, the distal end (tip) of the long insertion portion 301 of the biopsy forceps 300 is inserted into the lumen 40s of the sheath hub through the sealing hole 43a of the valve body 43, and then inserted into the lumen 30s of the tube. Due to its elastic force, the inner circumferential surface of the sealing hole 43a of the valve body 43 adheres tightly to the outer circumferential surface of the long insertion portion 301 of the biopsy forceps 300, and the airtightness of the lumen 40s of the sheath hub is maintained without the need for locking operations such as screw fastening.

[0061] Then, the forceps portion 302, located at the distal end of the long insertion portion 301 of the biopsy forceps 300, is exposed into the bile duct 103 from the tip portion 30a of the tube. This state (third state) is shown in Figure 10. The forceps portion 302 is opened and closed by operating the operating part (not shown) of the biopsy forceps 300 to collect tissue from the target site T. With the tissue collected, the long insertion portion 301 of the biopsy forceps 300 is withdrawn from the sheath 20, thereby removing the collected tissue from the body. When the biopsy forceps 300 is withdrawn, the valve body 43 closes the sealing hole 43a due to its elastic force, and the airtightness of the lumen 40s of the sheath hub is maintained without the need for locking operations such as screw fastening.

[0062] The method of using the endoscopic introducer 10 in this embodiment is not limited to the method described above. For example, without using the guidewire 201, the sheath tube 30 with the dilator 50 attached, which is led out from the instrument insertion channel of the endoscope 200, may be inserted into the bile duct 103 under X-ray fluoroscopy. Alternatively, the guidewire 201 may be inserted into the bile duct 103 after inserting the sheath tube 30 with the dilator 50 attached, which is led out from the instrument insertion channel of the endoscope 200, through the proximal opening 50b of the dilator.

[0063] The operation of the endoscopic introducer 10 in this embodiment will be described below.

[0064] The endoscopic introducer 10 in this embodiment is composed of a synthetic resin composition to which a contrast-enhanced material having radiopaqueness to X-rays is added, and comprises a sheath tube 30 inserted into the body using an endoscope 200, a hollow sheath hub 40 connected to the proximal end of the sheath tube 30. The sheath hub 40 is composed of a sheath hub tip portion 41 connected to the proximal end of the sheath tube 30, a side injection tube connection portion 45 branching from the sheath hub lumen 40s of the sheath hub 40 and opening laterally, and a sheath hub base portion 42 sealed by a valve body 43. The valve body 43 is made of an elastic material, and a sealing hole 43a is formed in the center of the valve body 43.

[0065] With the above configuration, contrast agent can be injected into the body through the side injection tube connection 45, and the long insertion portion 301 of various treatment instruments such as biopsy forceps 300 can be inserted into the body by passing it through the sealing hole 43a of the valve body 43 provided at the base end 42 of the sheath hub. The inner circumferential surface of the sealing hole 43a of the valve body 43, which is made of an elastic material, adheres tightly to the outer circumferential surface of the long insertion portion of various treatment instruments (for example, the long insertion portion 301 of the biopsy forceps 300) that passes through the sealing hole 43a of the valve body 43 due to its elastic force, and the airtightness of the lumen 40s of the sheath hub can be maintained. As a result, locking operations such as screwing are unnecessary, and operability can be improved.

[0066] Furthermore, with the above configuration, since the sheath tube 30 contains a material that is radiopaque to X-rays, the position of the sheath tube 30 can be confirmed under X-ray fluoroscopy, and the sheath tube 30 can be safely and reliably positioned.

[0067] In the endoscopic introducer 10 of this embodiment, a blade layer 33 may be embedded in the sheath tube 30.

[0068] According to the above configuration, the strength of the sheath tube 30 can be improved, and user operations can be appropriately transmitted to improve operability such as advancing and retracting movements and positioning operations within the body.

[0069] The endoscopic introducer 10 in this embodiment includes a dilator 50 comprising a dilator tube 60 that can be inserted into the sheath tube 30 by passing through the sealing hole 43a of the valve body 43, and a dilator hub 70 that can be attached to the base end 42 of the sheath hub. The distal end of the dilator tube 60 is tapered, and the distal end of the dilator tube 60 may be exposed from the tip opening of the sheath tube 30 when the dilator hub 70 is attached to the base end 42 of the sheath hub.

[0070] With the above configuration, the dilator tube 60, whose distal end is tapered, can be inserted into the body with the dilator tube 60 exposed from the sheath tube 30, allowing the sheath tube 30 to be safely and smoothly inserted into narrow tubular organs such as the bile duct 103 and the pancreatic duct.

[0071] The embodiments described above are provided to facilitate understanding of the present invention and do not limit it. Each component disclosed in the embodiments described above is intended to include all design modifications and equivalents that fall within the technical scope of the present invention. Furthermore, configurations obtained by appropriately combining each component described in each embodiment are also included in the present invention. [Explanation of Symbols]

[0072] 10 Endoscopic Introducer 20 sheaths 30 Sheath tubes 30a Tube tip 30b Tube base 30s tube lumen 31 Inner Layer 32 Outer layer 33 blade layers 35 Contrast Markers 40 Seahub 40s Sheath hub lumen 41. Sheath hub tip 41a Sheath hub tip opening 42 Sheath hub base 42a Sheath hub base opening 43 Valve body 43a Contact hole 44 Engagement protrusion 45 Side injection pipe connection 45a through hole 46 Side injection tube 47 Three-way stopcock 50 dilators 50a Dilator tip opening 50b Dilator proximal opening 50s dilator lumen 60 Dilator Tubes 60a Tapered section 70 Dilator Hub 71 recess 73 Inclined protrusion 101 Duodenum 102 Duodenal papilla 103 Bile duct 104 Hepatic hilum 200 Endoscopes 201 Guidewire 300 Biopsy Forceps 301 Long insertion section 302 Forceps section T Target area

Claims

1. A sheath tube is inserted into the body via an endoscope, comprising a synthetic resin composition to which a contrast-enhancing material having radiopaqueness to X-rays is added, A hollow sheath hub connected to the proximal end of the sheath tube, An endoscopic introducer comprising, The sheath hub is configured to include a sheath hub tip connected to the proximal end of the sheath tube, a side injection tube connection portion branching from the lumen of the sheath hub and opening laterally, and a sheath hub base end sealed by a valve body. An endoscopic introducer characterized in that the valve body is made of an elastic material and a sealing hole is formed in the center of the valve body.

2. The endoscopic introducer according to claim 1, characterized in that a blade layer is embedded in the sheath tube.

3. The dilator comprises a dilator tube that can be inserted into the sheath tube by passing through the sealing hole of the valve body, and a dilator hub that can be attached to the base end of the sheath hub, The endoscopic introducer according to claim 1 or 2, characterized in that the distal end of the dilator tube is tapered, and when the dilator hub is attached to the base end of the sheath hub, the distal end of the dilator tube is exposed from the tip opening of the sheath tube.

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