Endoscopic treatment tools

Abstract

An endoscope treatment tool (1) that is inserted into a forceps channel of an endoscope, the endoscope treatment tool (1) comprising: an outer tube (10) which has a first end and a second end in the longitudinal direction and has an inner cavity (11) that extends in the longitudinal direction; an inner tube (20) which is disposed in the inner cavity (11) of the outer tube (10), is movable in the longitudinal direction relative to the outer tube (10), and has an inner cavity (21); and a needle (30) which is disposed in the inner cavity (21) of the inner tube (20) and is movable in the longitudinal direction relative to the inner tube (20).

Description

[Technical field]

[0001] The present invention relates to an endoscopic treatment tool and an operating method thereof. [Background technology]

[0002] In the treatment of tumors such as cancer, a method has been proposed in which target tissue is sampled using a diagnostic instrument such as a biopsy needle to make a definitive diagnosis, and then a treatment instrument such as a drug injection catheter is used to inject a drug into the tissue.

[0003] As a treatment device, Patent Document 1 discloses a catheter for delivering a therapeutic agent into a substrate. The catheter is equipped with a curved delivery member including one or more lumens and a hollow tube. Patent Document 1 also discloses that the curved delivery member includes an opening at its distal tip and that the curved delivery member is a hollow needle. Patent Document 2 discloses a drainage catheter with an inner needle for puncturing and inserting into the body to aspirate and discharge fluids, etc. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2012-525181 [Patent Document 2] Japanese Patent Application Publication No. 8-52220 Summary of the Invention [Problem to be solved by the invention]

[0005] When an affected area such as a tumor is close to the body surface, for example, the affected area can be visually confirmed, the needle of the instrument described in Patent Documents 1-2 can be inserted into the affected area, and a drug can be directly injected from the needle into the affected area to perform treatment. However, in the past, a diagnostic instrument such as a biopsy needle for identifying the affected area and a treatment instrument such as a drug injection catheter were separate. For this reason, when the affected area is in an organ deep inside the body, such as the lung, liver, pancreas, or bile duct, it is not easy for the surgeon to visually identify the affected area, and even if the affected area is identified with a diagnostic instrument, it is not necessarily possible to accurately place a treatment instrument on the affected area and perform treatment such as injecting a drug. Therefore, the present invention aims to provide an endoscopic treatment instrument and an operating method thereof that can appropriately place a treatment instrument on the identified affected area even if the identified affected area is deep inside the body. [Means for solving the problem]

[0006] One embodiment of the endoscopic treatment tool of the present invention that has achieved the above object is an endoscopic treatment tool that is inserted into a forceps channel of an endoscope, and includes an outer tube having a first end and a second end in a longitudinal direction and a lumen extending in the longitudinal direction, an inner tube that is disposed in the lumen of the outer tube and is movable in the longitudinal direction of the outer tube relative to the outer tube, and has a lumen, and a needle that is disposed in the lumen of the inner tube and is movable in the longitudinal direction of the outer tube relative to the inner tube. According to the endoscopic treatment tool, after the inner tube and the needle are punctured into the target tissue, the needle can be moved proximally relative to the inner tube. Therefore, it is possible to remove the needle while the inner tube is fixed to the target tissue, and an instrument other than the needle, such as a treatment instrument, can be inserted into the removed portion. This allows the insertion position of the needle relative to the target tissue to coincide with the insertion position of the other instrument. By configuring the endoscopic treatment tool in this way, even if a site identified as an affected area such as a tumor is deep in the body, the treatment instrument can be placed in the identified affected area, making it possible to perform appropriate treatment.

[0007] In the above-mentioned endoscopic treatment tool, it is preferable that the needle can be removed from the inner cylinder in a state in which the inner cylinder protrudes distally beyond the outer cylinder.

[0008] It is preferable that the above-mentioned endoscopic treatment tool further includes a fluid supplier, the fluid supplier being connected to the proximal portion of the inner tube for supplying fluid to the inner cavity of the inner tube, and the inner tube having a side hole at its distal end for connecting the inner cavity of the inner tube with the outside of the inner tube.

[0009] In the above-mentioned endoscopic treatment tool, it is preferable that the inner cylinder has a tapered portion whose outer diameter decreases toward the distal side of the inner cylinder, and that the tapered portion is located distal to the side hole.

[0010] In the above-mentioned endoscopic treatment tool, it is preferable that the inner tube has an abutment portion where the inner wall of the inner tube abuts against the outer wall of the needle, and a separation portion located proximal to the abutment portion where the inner wall of the inner tube is separated from the outer wall of the needle.

[0011] In the above-mentioned endoscopic treatment tool, it is preferable that the cross-sectional area of ​​the distal end portion of the outer tube is larger than the cross-sectional area of ​​the outer tube at a central position in the longitudinal axis direction.

[0012] In the above-mentioned endoscopic treatment tool, it is preferable that the needle has an ultrasonic reflecting portion at its distal end.

[0013] In the above-mentioned endoscopic treatment tool, it is preferable that the ultrasonic reflecting portion has a first reflecting portion and a second reflecting portion located closer to the first reflecting portion.

[0014] In the above-mentioned endoscopic treatment tool, the first reflecting portion and the second reflecting portion are preferably uneven portions provided on the outer surface of the needle.

[0015] In the above-mentioned endoscopic treatment tool, it is preferable that the needle has a hollow portion at its distal portion for sampling biological tissue.

[0016] In the above-mentioned endoscopic treatment tool, it is preferable that an expandable portion is provided in a portion of the distal portion of the inner tube that can be exposed from the outer tube.

[0017] In the above-mentioned endoscopic treatment tool, it is preferable that a first stopper protruding radially outward is provided at the proximal portion of the inner cylinder.

[0018] In the above-mentioned endoscopic treatment tool, it is preferable that the inner tube has a small diameter portion whose inner diameter at a distal end is smaller than the center position in the longitudinal axis direction of the inner tube, the needle has an engagement portion whose outer diameter is larger than the small diameter portion, and the small diameter portion is located distal to the engagement portion.

[0019] It is preferable that the needle is removable from the inner cylinder, and the endoscopic treatment tool further includes a treatment instrument that is disposed in the inner cavity of the inner cylinder and is movable relative to the outer cylinder in the longitudinal direction of the outer cylinder.

[0020] The present invention also provides a method for operating an endoscopic treatment tool. One embodiment of the method for operating an endoscopic treatment tool of the present invention, which has achieved the above object, is a method for operating an endoscopic treatment tool including an outer tube having a first end and a second end in a longitudinal direction and a lumen extending in the longitudinal direction, an inner tube arranged in the lumen of the outer tube, movable in the longitudinal direction of the outer tube relative to the outer tube, and having a lumen, and a needle arranged in the lumen of the inner tube, movable in the longitudinal direction of the outer tube relative to the inner tube, and includes a step of inserting the endoscopic treatment tool into a forceps channel of an endoscope, a step of projecting the inner tube and the needle from the distal side of the outer tube, a step of removing the needle from the inner tube, and a step of inserting a treatment tool into the lumen of the inner tube after the step of removing the needle from the inner tube. Since the above-mentioned operating method includes a step of inserting a treatment tool into the lumen of the inner tube after the step of removing the needle from the inner tube, the insertion position of the needle with respect to the target tissue can be matched with the insertion position of the treatment tool. This makes it possible to place a treatment instrument at an affected area, such as a tumor, even if the affected area is deep inside the body, thereby enabling appropriate treatment. Effect of the Invention

[0021] In the above-mentioned endoscopic treatment tool, after the inner cylinder and the needle are inserted into the target tissue, the needle can be moved proximally relative to the inner cylinder. Therefore, the needle can be removed while the inner cylinder is fixed to the target tissue, and an instrument other than the needle, such as a treatment instrument, can be inserted into the removed site. This allows the insertion position of the needle into the target tissue to coincide with the insertion position of the other instrument. By configuring the endoscopic treatment tool in this way, even if a site identified as an affected area such as a tumor is deep in the body, the treatment instrument can be placed in the identified affected area, making it possible to perform appropriate treatment. In addition, since the above-mentioned operating method includes a step of inserting a treatment instrument into the inner cavity of the inner tube after the step of removing the needle from the inner tube, the insertion position of the needle with respect to the target tissue can be matched with the insertion position of the treatment instrument. This allows the treatment instrument to be placed in the identified affected area, such as a tumor, even if the area identified as the affected area is deep in the body, making it possible to perform appropriate treatment. [Brief description of the drawings]

[0022] [Figure 1] 1 is a cross-sectional view (partially a side view) of an endoscopic treatment tool according to one embodiment of the present invention; [Diagram 2] 2 is a schematic diagram showing a state in which an inner cylinder and a needle of the endoscopic treatment tool shown in FIG. 1 are inserted into biological tissue. [Diagram 3] 3 is a schematic diagram showing a state in which the needle of the endoscopic treatment instrument shown in FIG. 2 has been removed. [Figure 4] 3 is a schematic diagram showing a state in which a treatment instrument is inserted into the inner cavity of the inner cylinder of the endoscopic treatment tool shown in FIG. 2. [Diagram 5] 1. FIG. 4 is a cross-sectional view (partially a side view) showing a modified example of the endoscopic treatment tool shown in FIG. [Figure 6] 1. FIG. 4 is a cross-sectional view (partially a side view) showing another modified example of the endoscopic treatment tool shown in FIG. [Figure 7] 1. FIG. 4 is a cross-sectional view (partially a side view) showing still another modified example of the endoscopic treatment tool shown in FIG. [Figure 8]8 is a schematic diagram showing a state in which the inner cylinder and needle of the endoscopic treatment tool shown in FIG. 7 are inserted into biological tissue. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The present invention will be described in more detail below based on the following embodiments, but the present invention is not limited to the following embodiments, and can be modified as long as it meets the purpose described above and below, and all of these modifications are included in the technical scope of the present invention. In addition, hatching and component symbols may be omitted in each drawing for convenience, but in such cases, the specification and other drawings should be referred to. In addition, the dimensions of various components in the drawings may differ from the actual dimensions because priority is given to helping understand the features of the present invention.

[0024] 1. Endoscopic treatment tools One embodiment of the endoscopic treatment tool of the present invention is an endoscopic treatment tool inserted into a forceps channel of an endoscope, the gist being that the endoscopic treatment tool includes an outer tube having a first end and a second end in a longitudinal direction and a lumen extending in the longitudinal direction, an inner tube disposed in the lumen of the outer tube and movable in the longitudinal direction of the outer tube relative to the outer tube, and a needle disposed in the lumen of the inner tube and movable in the longitudinal direction of the outer tube relative to the inner tube. According to the endoscopic treatment tool, after the inner tube and the needle are punctured into the target tissue, the needle can be moved proximally relative to the inner tube. Therefore, the needle can be removed while the inner tube is fixed to the target tissue, and an instrument other than the needle, for example, a treatment instrument, can be inserted into the removed portion. This allows the insertion position of the needle relative to the target tissue to coincide with the insertion position of the other instrument. By configuring the endoscopic treatment tool in this way, even if a site identified as an affected area such as a tumor is deep in the body, the treatment instrument can be placed in the identified affected area, making it possible to perform appropriate treatment.

[0025] In the present invention, the endoscopic treatment tool is a treatment tool used to collect target tissue from a body cavity in an endoscopic operation, and to perform various treatments such as injection of medicine, heating, cauterization, light therapy, ultrasonic therapy, and shock wave therapy on the target tissue. The endoscopic treatment tool is inserted into a forceps channel of an endoscope (preferably an ultrasonic endoscope), placed inside the body from the distal side of the forceps channel of the endoscope, and delivered to a treatment site. The endoscopic treatment tool can be used to treat the biological tissue of any organ, but is preferably used to treat the tissue of organs located deep inside the body, such as the lung, liver, pancreas, and bile duct. In addition, the endoscopic treatment tool can be preferably used in various treatments such as gene therapy, photoimmunotherapy, photodynamic therapy, and anticancer drug local injection therapy, and is particularly preferably used in endoscopic ultrasonic fine needle aspiration (EUS-FNA). Hereinafter, the endoscopic treatment tool may be simply referred to as a treatment tool.

[0026] The basic configuration of an endoscopic treatment tool will be described with reference to Figs. 1 to 4. Fig. 1 shows a cross-sectional view (partially a side view) of an endoscopic treatment tool according to one embodiment of the present invention. Fig. 2 shows a schematic diagram showing a state in which an inner tube and a needle of the endoscopic treatment tool shown in Fig. 1 are inserted into biological tissue. Fig. 3 shows a schematic diagram showing a state in which the needle of the endoscopic treatment tool shown in Fig. 2 has been removed. Fig. 4 shows a schematic diagram showing a state in which a treatment instrument has been inserted into the inner cavity of the inner tube of the endoscopic treatment tool shown in Fig. 2. The endoscopic treatment tool 1 includes an outer tube 10, an inner tube 20, and a needle 30.

[0027] In the present invention, the distal side of the endoscopic treatment tool 1 refers to the first end side in the longitudinal direction of the outer tube 10, which is the side to be treated. The proximal side of the endoscopic treatment tool 1 refers to the second end side in the longitudinal direction of the outer tube 10, which is the hand side of the user (operator). When each member is divided into two equal parts in the longitudinal direction, the proximal side may be referred to as the proximal part, and the distal side may be referred to as the distal part. The inward side of the endoscopic treatment tool 1 refers to the direction toward the center of the longitudinal axis of the outer tube 10 in the radial direction of the outer tube 10, and the outward side refers to the radial direction opposite to the inward side.

[0028] It is desirable that the materials of the members constituting the endoscopic treatment tool 1 have biocompatibility.

[0029] As shown in FIG. 1, the outer cylinder 10 is a member having a first end and a second end in the longitudinal direction and an inner cavity 11 extending in the longitudinal direction. Preferably, the first end corresponds to the distal end of the outer cylinder 10, and the second end corresponds to the proximal end of the outer cylinder 10. The outer cylinder 10 has a tubular structure for disposing the inner cylinder 20 and the needle 30 in the inner cavity 11 of the outer cylinder 10 so as not to damage tissue sites not to be treated or the inside of the forceps channel of the endoscope. In addition, since the outer cylinder 10 is inserted into the body, it is preferably flexible. The outer cylinder 10 communicates with the outside through an opening provided in its distal portion. When the inner cylinder 20 and the needle 30 are inserted into the target tissue, the inner cylinder 20 and the needle 30 are protruded from the opening.

[0030] The outer tube 10 may be a resin tube, a cylindrical body formed by arranging a single wire, a plurality of wires, or a stranded wire in a specific pattern, a metal tube, or a combination of these. The resin tube may be manufactured by extrusion molding, for example. Examples of the cylindrical body in which the wires are arranged in a specific pattern include a cylindrical body having a mesh structure formed by simply crossing or weaving the wires, and a coil in which the wires are wound. The type of mesh structure is not particularly limited, and the number of turns and density of the coil are also not particularly limited. The mesh structure or the coil may be formed with a constant density throughout the axial direction, or may be formed with a different density depending on the position in the longitudinal direction. In order to increase the flexibility of the metal tube, a plurality of annular grooves or spiral grooves may be formed on the outer surface of the metal tube. Among them, it is preferable that the grooves are formed on the outer surface, particularly the outer circumferential surface, distal to the center in the axial direction of the metal tube.

[0031] The outer tube 10 is preferably made of a resin or a metal. Examples of the resin constituting the outer tube 10 include polyamide resin, polyester resin, polyurethane resin, polyolefin resin, fluorine resin, vinyl chloride resin, silicone resin, and natural rubber. These may be used alone or in combination of two or more. Among them, polyamide resin, polyester resin, polyurethane resin, polyolefin resin, and fluorine resin are preferably used. Examples of the metal constituting the outer tube 10 include stainless steel such as SUS304 and SUS316, platinum, nickel, cobalt, chromium, titanium, tungsten, gold, Ni-Ti alloy, Co-Cr alloy, and combinations thereof. In particular, the wire made of Ni-Ti alloy has excellent shape memory and high elasticity. The wire may be a fiber material such as the above-mentioned metal, polyarylate fiber, aramid fiber, ultra-high molecular weight polyethylene fiber, PBO fiber, and carbon fiber. The fiber material may be a monofilament or a multifilament. Moreover, the outer cylinder 10 may be a cylindrical body made of resin with a reinforcing material such as a metal wire disposed therein.

[0032] The outer cylinder 10 may be made of a single layer or multiple layers. Also, in the longitudinal axial direction, a part of the outer cylinder 10 may be made of a single layer, and another part may be made of multiple layers.

[0033] It is preferable that the cross-sectional area of ​​the distal end of the outer cylinder 10 is larger than the cross-sectional area at the center position in the longitudinal direction of the outer cylinder 10. This makes it easier for the distal end of the outer cylinder 10 to abut against an internal organ (e.g., a body cavity wall), thereby making it possible to fix the position of the treatment tool 1 inside the body.

[0034] The inner cylinder 20 is disposed in the inner cavity 11 of the outer cylinder 10, is movable in the longitudinal direction of the outer cylinder 10 relative to the outer cylinder 10, and has an inner cavity 21. The inner cylinder 20 also has a distal portion and a proximal portion. The inner cylinder 20 is inserted into the target tissue by puncturing together with the needle 30. The inner cylinder 20 can fix the position of the treatment tool 1 inside the body.

[0035] The inner tube 20 can be made of the resin or metal described above as the constituent material of the outer tube 10. The material of the inner tube 20 may be the same as or different from the material of the outer tube 10. As with the outer tube 10, the inner tube 20 can be a resin tube, a cylindrical body formed by arranging a single wire or multiple wires, or stranded wires in a specific pattern, a metal tube, or a combination of these.

[0036] The Shore hardness of the outer cylinder 10 is preferably greater than the Shore hardness of the inner cylinder 20. This makes it possible to prevent excessive bending of the outer cylinder 10 while ensuring appropriate flexibility of the inner cylinder 20. The Shore hardness is measured based on the ISO868:2003 Plastic Durometer Hardness Testing Method.

[0037] Since the inner cylinder 20 is configured to be movable relative to the outer cylinder 10 in the longitudinal direction of the outer cylinder 10, it is preferable that the inner cylinder 20 and the outer cylinder 10 are not fixed to each other.

[0038] The longitudinal axis direction of the inner cylinder 20 is preferably parallel to the longitudinal axis direction of the outer cylinder 10. This allows the inner cylinder 20 to easily move along the longitudinal axis direction of the outer cylinder 10.

[0039] It is preferable that the distal end (more preferably a portion including the distal end) of the inner cylinder 20 is provided with a tapered portion 23 in which the outer diameter decreases toward the distal side of the inner cylinder 20. This makes it easier to insert the inner cylinder 20 together with the needle 30 into the target tissue by puncturing.

[0040] The needle 30 is disposed in the inner cavity 21 of the inner cylinder 20 and is movable in the longitudinal direction of the outer cylinder 10 relative to the inner cylinder 20. The needle 30 is preferably disposed in the inner cavity 21 of the inner cylinder 20 so that a tip 31 of the needle 30 is located on the distal side. The needle 30 is inserted into the target tissue together with the inner cylinder 20 by puncturing. By puncturing the target tissue with the needle 30, treatment such as collection of biological tissue and injection of medicine can be performed.

[0041] Here, an application example of the treatment tool 1 for pancreatic cancer will be described. First, the insertion part of the ultrasonic endoscope is inserted into the stomach, and the treatment tool 1 is protruded from the distal opening of the forceps channel of the ultrasonic endoscope. As shown in FIG. 2, the inner tube 20 and the needle 30 are protruded from the opening at the distal end of the outer tube 10, and the inner tube 20 and the needle 30 are punctured into the target tissue. For example, in the case of treating pancreatic cancer, the target tissue is pancreatic tissue. By puncturing the stomach wall and the pancreatic wall with the inner tube 20 and the needle 30, the treatment tool 1 placed in the stomach reaches the pancreas, which is the target tissue. In this case, the first body cavity wall 61 is the stomach wall, and the second body cavity wall 62 is the pancreatic wall. Next, by moving the needle 30 proximally relative to the inner tube 20, it becomes possible to remove the needle 30 while the inner tube 20 is fixed to the target tissue, as shown in FIG. 3. At this time, the needle 30 can function as a biopsy needle for collecting biological tissue. When the collected tissue is definitively diagnosed as a malignant tumor, a treatment instrument 70 is inserted into the location from which the needle 30 was removed, i.e., into the inner cavity 21 of the inner cylinder 20, as shown in Fig. 4. This allows the insertion position of the needle 30 with respect to the target tissue to coincide with the insertion position of the treatment instrument 70. By configuring the treatment tool 1 in this way, even if a site identified as an affected area such as a malignant tumor is deep in the body, the treatment instrument 70 can be placed at the identified affected area, making it possible to perform appropriate treatment.

[0042] The distal end of needle 30 is not particularly limited as long as it is formed so as to easily puncture tissue, but it is preferable that needle 30 has a beveled opening edge 32 at the distal end as shown in FIG. 1.

[0043] It is preferable that the tip 31 of the needle 30 can protrude from the distal opening of the inner cylinder 20. It is preferable that the tip 31 of the needle 30 is located distal to the distal end of the inner cylinder 20 when the needle 30 is moved to the most distal side relative to the inner cylinder 20 so that the tip 31 of the needle 30 can puncture tissue prior to the inner cylinder 20.

[0044] It is preferable that the inner diameter of the distal end of the inner cylinder 20 is smaller than that of the central position in the longitudinal direction of the inner cylinder 20, and that the needle 30 has an engagement portion 34 with an outer diameter larger than that of the small diameter portion 27, and that the small diameter portion 27 is located distal to the engagement portion 34. This makes it possible to fix the position of the needle 30 in the longitudinal direction relative to the inner cylinder 20, thereby preventing the needle 30 from protruding too far from the opening at the distal end of the inner cylinder 20.

[0045] The maximum outer diameter of the engagement portion 34 of the needle 30 is preferably smaller than the maximum inner diameter of the inner tube 20. This makes it easier to move the inner tube 20 and the needle 30 relatively in the longitudinal axis direction of the inner tube 20.

[0046] The engaging portion 34 may be one or more protrusions provided on the outside of the needle 30. The needle 30 may also have a needle body extending in the longitudinal direction and a ring-shaped member provided on the outside of the needle body as the engaging portion 34. The engaging portion 34 may be integrally formed with the needle body, or may be a separate member from the needle body. Thus, the engaging portion 34 may be made of the same material as the needle body, or may be made of a different material from the needle body.

[0047] Since the needle 30 is configured to be movable relative to the inner cylinder 20 in the longitudinal direction of the inner cylinder 20, it is preferable that the needle 30 and the inner cylinder 20 are not fixed to each other.

[0048] The longitudinal direction of the needle 30 is preferably parallel to the longitudinal direction of the inner cylinder 20. This makes it easier for the needle 30 to move along the longitudinal direction of the inner cylinder 20, so that when the needle 30 is protruded from the distal opening of the inner cylinder 20, the tip 31 of the needle 30 is less likely to come into contact with the distal end of the inner cylinder 20.

[0049] The needle 30 preferably has a hollow portion 33 at its distal end for sampling biological tissue, thereby allowing the target tissue to be held within the hollow portion 33 for biopsy.

[0050] Although not shown, the needle 30 may be solid on the proximal side of the hollow portion 33. By forming at least a part of the needle 30 in the longitudinal direction as the hollow portion 33 in this manner, the target tissue can also be held.

[0051] The hollow portion 33 of the needle 30 may be provided over the entire longitudinal axis direction of the needle 30. For example, the needle 30 may be formed in a tubular shape such as a circular tube or an elliptical tube. By forming the hollow portion 33 in this manner, it is possible to increase the amount of target tissue that can be held within the hollow portion 33. Note that the elliptical tube shape includes tubes with an elliptical, egg-shaped, or rounded rectangular cross section.

[0052] When the needle 30 is used for drug injection, the cross-sectional shape perpendicular to the longitudinal axis of the needle 30 is preferably circular or elliptical in order to improve the flow of liquid in the hollow portion of the needle 30. The elliptical shape includes an elliptical shape, an egg shape, and a rounded rectangular shape. The same applies to the following explanation.

[0053] As materials for forming the needle 30, the resin materials and metal materials listed as the preferred materials for the outer tube 10 and the inner tube 20 can be used.

[0054] 1, the needle 30 is preferably disposed over the entire longitudinal axis direction of the inner cavity 21 of the inner cylinder 20. The proximal end of the needle 30 is preferably located closer to the proximal end of the outer cylinder 10. The proximal end of the needle 30 is preferably located closer to the proximal end of the inner cylinder 20. This makes it easier to move the needle 30 relative to the inner cylinder 20 in the longitudinal axis direction of the inner cylinder 20.

[0055] 3, it is preferable that the needle 30 can be removed from the inner cylinder 20 in a state in which the inner cylinder 20 protrudes distally beyond the outer cylinder 10. This allows the inner cylinder 20 to be fixed inside the body even after the needle 30 is removed from the inner cylinder 20, making it possible to fix the insertion position of an instrument other than the needle 30, such as a treatment instrument.

[0056] The needle 30 is removable from the inner tube 20, and the endoscopic treatment tool 1 is preferably further provided with a treatment tool that is disposed in the inner cavity 21 of the inner tube 20 and is movable relative to the outer tube 10 in the longitudinal direction of the outer tube 10. This allows the needle 30 to be replaced with another tool while the inner tube 20 is fixed to the biological tissue. Fig. 4 shows an example in which a treatment tool 70 is disposed in the inner cavity 21 of the inner tube 20 after the needle 30 has been removed from the inner tube 20.

[0057] Therapeutic instruments are used to perform various types of treatments on target tissue, such as drug injection, heating, cauterization, light treatment, ultrasonic treatment, shock wave treatment, etc. Examples of therapeutic instruments include drug injection catheters, high-frequency treatment instruments equipped with electrodes for heating or cauterization, ultrasonic probes, light irradiation probes, laser probes, shock wave probes, and forceps.

[0058] The structure of the proximal part of the treatment tool 1 will be described with reference to FIG. 1. The proximal part of the inner tube 20 is preferably provided with an operating part 50 for the surgeon to grasp the treatment tool 1. The operating part 50 can be, for example, a single tube having one lumen 51, or a branched tube having a plurality of lumen 51. A fluid supplier 45 is preferably connected to the lumen 51 of the operating part 50. This allows a drug such as a contrast agent to be supplied into the inner tube 20. In FIG. 1, the operating part 50 is a Y-shaped tube having a lumen 51 branched in two directions.

[0059] The inner tube 20 or the needle 30 may be provided with a stopper 54 for fixing the positions of the components in the longitudinal direction. A cylindrical body can be used as the stopper 54. The stopper 54 can be fixed to the outside of the inner tube 20 or the needle 30 by inserting the inner tube 20 or the needle 30 into the inner cavity of the cylindrical body.

[0060] 1, a first stopper 55 protruding radially outward is preferably provided at the proximal portion of the inner tube 20. This makes it possible to fix the position of the inner tube 20 in the longitudinal direction relative to the outer tube 10, thereby preventing the inner tube 20 from protruding too far from the opening at the distal end of the outer tube 10.

[0061] The first stopper 55 only needs to protrude radially outward from the inner tube 20, and may protrude radially outward from the outer tube 10. The first stopper 55 abuts against the outer tube 10, making it easier to fix the position of the inner tube 20 relative to the outer tube 10 in the longitudinal direction.

[0062] The first stopper 55 is preferably disposed distal to the distal end of the operation portion 50. This makes it easier to move the inner tube 20 relative to the outer tube 10 in the longitudinal direction.

[0063] A first check valve 58 is connected to the distal portion of the first stopper 55, and the first check valve 58 is preferably in contact with the proximal end of the outer cylinder 10. In this case, it is more preferable that the first check valve 58 is in liquid-tight contact with the proximal end of the outer cylinder 10. This makes it possible to prevent bodily fluids mixed in the outer cylinder 10 from flowing back toward the hand side.

[0064] A second stopper 56 protruding radially outward is preferably provided at the proximal portion of the needle 30. This makes it possible to fix the position of the needle 30 in the longitudinal direction relative to the inner tube 20, thereby preventing the needle 30 from protruding too far from the opening at the distal end of the inner tube 20.

[0065] The second stopper 56 is preferably disposed on the proximal side relative to the first stopper 55. This makes it easier to move the needle 30 relative to the inner cylinder 20 in the longitudinal direction.

[0066] A second check valve 59 is connected to the distal portion of the second stopper 56, and the second check valve 59 is preferably in contact with the operation section 50. In this case, it is more preferable that the second check valve 59 is in liquid-tight contact with the operation section 50. This makes it possible to prevent the drug, such as the contrast medium, supplied to the lumen 21 of the inner cylinder 20 from flowing back toward the hand side.

[0067] The operating portion 50 and the stopper 54 may be made of a synthetic resin such as ABS or polycarbonate. The operating portion 50 and the stopper 54 may also be made of foamed plastic such as polyurethane foam.

[0068] The joining of the operating portion 50 and the inner cylinder 20, the first stopper 55 and the inner cylinder 20, or the second stopper 56 and the needle 30 can be carried out using a conventionally known joining means such as adhesive or thermal welding.

[0069] 5 is a cross-sectional view (partial side view) showing a modified example of the endoscopic treatment tool 1 shown in FIG. 1. As shown in FIG. 5, the treatment tool 1 preferably further includes a fluid supplier 45. In this case, the fluid supplier 45 for supplying fluid to the inner cavity 21 of the inner tube 20 is connected to the proximal part of the inner tube 20, and the inner tube 20 preferably has a side hole 24 at its distal end (more preferably, the peripheral wall of the distal end) for communicating the inner cavity 21 of the inner tube 20 with the outside of the inner tube 20. This allows a drug such as a contrast agent to be discharged from the side hole 24 using the fluid supplier 45, so that it is possible to know whether the needle 30 and the inner tube 20 have been inserted into the target tissue.

[0070] When the inner cylinder 20 is moved to the most distal side relative to the outer cylinder 10, the side hole 24 is preferably located distal to the distal end of the outer cylinder 10. This makes it possible to release the drug into the target tissue.

[0071] The number of side holes 24 is not particularly limited, and there may be only one or more. When multiple side holes 24 are provided, the multiple side holes 24 are preferably arranged side by side in the circumferential direction of the inner cylinder 20. The shape of the side hole 24 is not particularly limited, and may be a circle, an oval, a polygon, or a combination thereof.

[0072] The fluid supply 45 may be a syringe or a motor-controlled infusion pump.

[0073] The inner cylinder 20 has a tapered section 23 whose outer diameter decreases toward the distal side of the inner cylinder 20, and the tapered section 23 is preferably located distal to the side hole 24. This makes it easier to insert the needle 30 and the inner cylinder 20 into the target tissue, and also makes it possible to inject a contrast agent into the target tissue through the side hole 24 while these members are inserted into the target tissue. As a result, it is possible to determine whether the needle 30 and the inner cylinder 20 have been inserted into the target tissue using an imaging diagnostic device such as an ultrasonic endoscope, PET, MRI, or X-ray CT.

[0074] The inner cylinder 20 preferably has an abutment portion 25 where the inner wall of the inner cylinder 20 abuts against the outer wall of the needle 30, and a separation portion 26 located closer to the abutment portion 25 and where the inner wall of the inner cylinder 20 is spaced apart from the outer wall of the needle 30. This allows the needle 30 and the inner cylinder 20 to abut against each other, thereby preventing leakage of the drug from the inner cylinder 20. It is more preferable that the abutment portion 25 is a portion where the inner wall of the inner cylinder 25 abuts against the outer wall of the needle 30. It is more preferable that the separation portion 26 is a portion where the inner wall of the inner cylinder 20 is spaced apart from the outer wall of the needle 30, located closer to the abutment portion 25.

[0075] The abutment portion 25 of the inner cylinder 20 is preferably disposed at the distal end portion of the inner cylinder 20. This makes it possible to prevent leakage of the drug from the distal side of the inner cylinder 20.

[0076] The side hole 24 of the inner cylinder 20 is preferably disposed in the separated portion 26. This allows a drug such as a contrast agent supplied to the lumen 21 of the inner cylinder 20 to be discharged to the outside through the side hole 24.

[0077] The side hole 24 of the inner cylinder 20 is preferably located more proximal than the proximal end of the engagement part 34. This allows a drug such as a contrast agent to flow toward the side hole 24 without passing through a portion where the lumen 21 of the inner cylinder 20 is narrowed by the presence of the engagement part 34, making it easier to release the drug from the side hole 24.

[0078] It is preferable that the inner cylinder 20 and the needle 30 are movable relative to each other in the longitudinal direction of the inner cylinder 20, and that the inner cylinder 20 and the needle 30 are in liquid-tight contact with each other at the distal end of the inner cylinder 20. This can prevent leakage of the drug from the distal side of the inner cylinder 20.

[0079] Fig. 6 is a cross-sectional view (partial side view) showing another modified example of the endoscopic treatment tool 1 shown in Fig. 1. As shown in Fig. 6, the needle 30 preferably has an ultrasonic reflecting part 35 at its distal end. When the needle 30 and the inner tube 20 are inserted into body tissue, ultrasonic waves are emitted toward the ultrasonic reflecting part 35, and the time and intensity of the ultrasonic waves reflected by the ultrasonic reflecting part 35 until they return can be measured to determine whether the needle 30 and the inner tube 20 have been inserted into the target tissue.

[0080] The ultrasonic reflecting section 35 preferably has a first reflecting section 35A and a second reflecting section 35B located closer to the first reflecting section 35A. By arranging the first reflecting section 35A and the second reflecting section 35B apart from each other in the longitudinal axis direction of the needle 30, it is possible to use the two reflecting sections to determine whether the needle 30 and the inner cylinder 20 have been inserted into the target tissue.

[0081] When the needle 30 is moved to the most distal side relative to the inner cylinder 20, it is preferable that the first reflecting portion 35A is located distal to the distal end of the inner cylinder 20, and the second reflecting portion 35B is located proximal to the distal end of the inner cylinder 20. This makes it possible to know that the needle 30 has been inserted into the target tissue when the reflection from the first reflecting portion 35A is measured, and to know that the inner cylinder 20 has been inserted into the target tissue when the reflection from the second reflecting portion 35B is measured.

[0082] The first reflecting portion 35A and the second reflecting portion 35B are preferably unevenness 36 provided on the outer surface of the needle 30. Providing such unevenness 36 on the needle 30 makes it possible to reflect ultrasonic waves. Note that the unevenness 36 is preferably provided on the outer circumferential surface of the needle 30.

[0083] The unevenness 36 is a portion in which recesses 37 and protrusions 38 are arranged alternately. It is preferable that a plurality of recesses 37 and protrusions 38 are provided. It is preferable that the unevenness 36 is provided on at least a portion of the circumference of the needle 30, and it is preferable that the unevenness 36 is arranged over the entire circumference of the needle 30.

[0084] Although there are no particular limitations on the arrangement of the irregularities 36, it is preferable that the recesses 37 and the protrusions 38 are arranged side by side in the longitudinal direction or circumferential direction of the needle 30, and it is more preferable that they are arranged at equal intervals in the longitudinal direction or circumferential direction of the needle 30. Figure 6 shows an example in which the recesses 37 and the protrusions 38 are arranged side by side in the longitudinal direction of the needle 30.

[0085] The protrusions 38 may extend along the longitudinal axis direction of the needle 30, or may extend along the circumferential direction of the needle 30. Furthermore, a plurality of protrusions 38 may be arranged side by side in a stripe pattern.

[0086] The arrangement of the first reflecting portion 35A and the second reflecting portion 35B may be the same. In order to easily distinguish the first reflecting portion 35A from the second reflecting portion 35B, the arrangement of the projections and recesses 36 of the first reflecting portion 35A and the second reflecting portion 35B may be different. For example, the arrangement interval of the recesses 37 and the projections 38 in the first reflecting portion 35A may be different from the arrangement interval of the recesses 37 and the projections 38 in the second reflecting portion 35B.

[0087] In order to reflect ultrasound, it is preferable that at least the portion of needle 30 in the longitudinal direction where ultrasound reflecting portion 35 is provided is made of metal, and it is more preferable that needle 30 is made of metal throughout its entire longitudinal direction.

[0088] The treatment tool 1 may include an ultrasonic transducer that converts an electrical signal into ultrasonic waves and transmits and receives ultrasonic waves. The ultrasonic transducer preferably includes a piezoelectric vibrator that vibrates when a voltage is applied, and the piezoelectric vibrator may be made of, for example, piezoelectric ceramics or quartz crystal.

[0089] FIG. 7 is a cross-sectional view (partial side view) showing yet another modified example of the endoscopic treatment tool 1 shown in FIG. 1, and FIG. 8 is a schematic diagram showing the state in which the inner tube 20 and the needle 30 of the endoscopic treatment tool 1 shown in FIG. 7 are inserted into biological tissue. It is preferable that the expandable part 40 is provided in a part of the distal part of the inner tube 20 that can be exposed from the outer tube 10. Thereby, after confirming that the distal end part of the inner tube 20 has been inserted into the target tissue, the expandable part 40 can be expanded to fix the distal end of the inner tube 20 in the body so that the position of the distal end does not shift. The expandable part 40 can be, for example, a balloon 41 as shown in FIG. 7. The expandable part may be an expansion wire or a basket composed of multiple elastic wires, in addition to the balloon 41.

[0090] The balloon 41 has, from the distal side, a distal fixed portion 42 fixed to the inner tube 20, an expansion portion 43 not fixed to the inner tube 20, and a proximal fixed portion 44 fixed to the inner tube 20.

[0091] When the balloon 41 is provided in the inner cylinder 20, it is preferable that a side hole 24 is provided at a position corresponding to the inflation portion 43 of the balloon 41, and a fluid supplier 45 is connected to the proximal portion of the inner cylinder 20. The balloon 41 is configured so that pressurized fluid is supplied from the fluid supplier 45 to the inside of the balloon 41 through the side hole 24 of the inner cylinder 20, and the supply of pressurized fluid to the inside of the balloon 41 makes it possible to expand the balloon 41. On the other hand, the balloon 41 can be deflated by drawing out the pressurized fluid from the inside of the balloon 41.

[0092] The type of fluid supplied into the balloon 41 is not particularly limited, but may be, for example, a liquid such as physiological saline, a contrast agent, or a mixture thereof, or a gas such as air, nitrogen, or carbon dioxide.

[0093] The balloon 41 is preferably made of a resin. Examples of resins constituting the balloon 41 include polyamide resins, polyester resins, polyurethane resins, polyolefin resins, vinyl chloride resins, silicone resins, and natural rubber. These may be used alone or in combination of two or more. Among these, polyamide resins, polyester resins, and polyurethane resins are preferably used. As these resins, elastomer resins can be used in terms of thinning the balloon 41 and flexibility.

[0094] Although not shown, in the deflated state of the balloon 41, it is preferable that the balloon 41 is wound around the outside of the inner tube 20. This allows the outer diameter of the inner tube 20 to be reduced when the balloon 41 is deflated, making it easier to insert the inner tube 20 into the target tissue.

[0095] The distal fixing portion 42 of the balloon 41 is preferably located more proximal than the tapered portion 23 of the inner cylinder 20. This makes it easier to insert the inner cylinder 20 into the target tissue.

[0096] 2. Method of operating endoscopic treatment tool The operating method of an endoscopic treatment tool 1 is described below, which includes an outer tube 10 having a first end and a second end in the longitudinal direction and an inner cavity 11 extending in the longitudinal direction, an inner tube 20 arranged in the inner cavity 11 of the outer tube 10 and movable in the longitudinal direction of the outer tube 10 relative to the outer tube 10, and having an inner cavity 21, and a needle 30 arranged in the inner cavity 21 of the inner tube 20 and movable in the longitudinal direction of the outer tube 10 relative to the inner tube 20.

[0097] The endoscopic treatment tool 1 is inserted into the forceps channel of the endoscope (Step 1). More specifically, the distal side of the treatment tool 1 is inserted into the proximal opening of the forceps channel of the endoscope. The endoscope is preferably an ultrasonic endoscope. In order to collect biological tissue using the needle 30, it is preferable that the needle 30 has a hollow portion 33. For other specific configurations of the treatment tool 1, please refer to the explanation in "1. Endoscopic treatment tool".

[0098] The inner cylinder 20 and the needle 30 are protruded from the distal side of the outer cylinder 10 (Step 2). In particular, it is preferable to protrude the inner cylinder 20 and the needle 30 from an opening on the distal side of the outer cylinder 10. This allows the inner cylinder 20 and the needle 30 to puncture the target tissue. Step 2 can be performed by moving the inner cylinder 20 and the needle 30 to the distal side relative to the outer cylinder 10.

[0099] When the inner cylinder 20 has a side hole 24, it is preferable to release a contrast agent from the side hole 24 of the inner cylinder 20 after step 2 (step 3). This makes it possible to determine whether the distal end of the inner cylinder 20 has been inserted into the target tissue using an imaging diagnostic device such as an ultrasonic endoscope, PET, MRI, or X-ray CT. This allows the distal end of a treatment instrument used in a subsequent step to be reliably positioned in the target tissue, improving the treatment effect.

[0100] When the needle 30 is provided with an ultrasonic reflecting portion 35, it is preferable to irradiate the ultrasonic reflecting portion 35 with ultrasonic waves (step 4). This step also makes it possible to determine whether the distal end portion of the inner cylinder 20 has been inserted into the target tissue.

[0101] When the inner cylinder 20 is provided with the expandable portion 40, it is preferable to expand the expandable portion 40 after step 2 (step 5). This allows the expandable portion 40 to be disposed between the first body cavity wall 61 and the second body cavity wall 62, and the inner cylinder 20 can be fixed inside the body so that the position of the inner cylinder 20 does not shift. Note that when the inner cylinder 20 is provided with a balloon 41 as the expandable portion 40, it is preferable that the balloon 41 is deflated and wound around the outside of the inner cylinder 20 in step 2.

[0102] The needle 30 is removed from the inner tube 20 (step 6). In step 6, it is preferable to move the needle 30 proximally relative to the inner tube 20 and remove the needle 30 from the proximal side of the inner tube 20. This makes it possible to insert the treatment instrument 70 into the portion where the needle 30 was placed in a later step. If the needle 30 has a hollow portion 33, the hollow portion 33 of the needle 30 can hold the biological tissue, making it possible to perform a definitive diagnosis of the biological tissue after step 6.

[0103] After the step of removing the needle 30 from the inner tube 20, a treatment instrument 70 is inserted into the lumen 21 of the inner tube 20 (step 7). Examples of the treatment instrument 70 include a drug injection catheter, a catheter provided with an electrode for heating or burning, an ultrasonic probe, a light irradiation probe, a laser probe, a shock wave probe, and forceps. Step 7 allows the insertion position of the needle 30 with respect to the target tissue to coincide with the insertion position of the treatment instrument 70. This allows the treatment instrument 70 to be placed in the identified affected area, even if the area identified as an affected area such as a tumor is deep in the body, making it possible to perform appropriate treatment.

[0104] After step 7, it is preferable to project the treatment instrument 70 from the distal side of the outer cylinder 10 (step 8). This makes it possible to perform treatment using the treatment instrument 70.

[0105] 3. Treatment methods using endoscopic treatment tools A treatment method using the endoscopic treatment tool 1 will be described. Here, an example of treating pancreatic cancer will be described. The first organ is the stomach, and the second organ is the pancreas. For the specific configuration of the treatment tool 1, please refer to the explanation in "1. Endoscopic treatment tool."

[0106] First, the endoscopic treatment tool 1 is inserted into an endoscope placed in a body cavity (step 10). The endoscope is preferably an ultrasonic endoscope. In the case of treating pancreatic cancer, the distal part of the ultrasonic endoscope is placed in the stomach.

[0107] The needle 30 and the inner cylinder 20 are inserted into the first body cavity wall 61 (step 11). In the case of treating pancreatic cancer, the first body cavity wall 61 is preferably the stomach wall.

[0108] The needle 30 and the inner cylinder 20 are inserted into the second body cavity wall 62 (step 12). Here, the second body cavity wall 62 is located more distally than the first inner cavity wall 61. In the case of treating pancreatic cancer, the second body cavity wall 62 is preferably a pancreatic wall. When the needle 30 has a hollow portion 33, the needle 30 penetrates the second body cavity wall 62, and pancreatic tissue is taken into the hollow portion 33 of the needle 30.

[0109] When the expandable portion 40 is provided on the inner tube 20, it is preferable to expand the expandable portion 40 after step 12 (step 13). This allows the expandable portion 40 to be disposed between the first body cavity wall 61 and the second body cavity wall 62, and the inner tube 20 can be fixed inside the body so that the position of the inner tube 20 does not shift. Note that when the inner tube 20 is provided with a balloon 41 as the expandable portion 40, it is preferable that the balloon 41 is deflated and wound around the outside of the inner tube 20 in steps 11 and 12. This allows the outer diameter of the inner tube 20 to be reduced even if the balloon 41 is provided on the inner tube 20, making it easier to insert the inner tube 20 into the target tissue.

[0110] When the inner cylinder 20 is provided with a side hole 24, it is preferable that the side hole 24 is disposed in a second organ (e.g., the pancreas) after step 12 (step 14). This makes it easier to inject a drug such as a contrast agent into the target tissue through the side hole 24 in step 15, which will be described later.

[0111] When the inner cylinder 20 has a side hole 24, it is preferable to inject a contrast agent into the target tissue from the side hole 24 of the inner cylinder 20 (step 15). This makes it possible to determine whether the distal end of the inner cylinder 20 has been inserted into the target tissue using an imaging diagnostic device such as an ultrasonic endoscope, PET, MRI, or X-ray CT. This allows the distal end of the treatment instrument 70 used in a subsequent process to be reliably positioned in the target tissue, improving the treatment effect. It is preferable to perform step 15 at least one of the following times: after step 11, after step 12, during step 11, and during step 12.

[0112] When the needle 30 is provided with an ultrasonic reflecting portion 35, it is preferable to irradiate the ultrasonic reflecting portion 35 with ultrasonic waves (step 16). This makes it possible to know whether the distal end portion of the inner tube 20 has been inserted into the target tissue. This step also makes it possible to know whether the distal end portion of the inner tube 20 has been inserted into the target tissue. It is preferable to perform step 16 from at least one of the timings before step 11, during step 11, after step 11, before step 12, during step 12, and after step 12, until the completion of step 12. Step 16 can also be performed together with step 15 or instead of step 15.

[0113] The needle 30 is removed from the first body cavity wall 61 and the second body cavity wall 62 (step 17).

[0114] A definitive diagnosis is made on the biological tissue collected by the needle 30 (step 18). For the definitive diagnosis, imaging diagnostic devices such as PET, MRI, and X-ray CT can be used, as well as a fluorescent spray. The fluorescent spray contains a fluorescent probe that reacts with a specific enzyme, such as γ-glutamyl transpeptidase (GGT), in cancer cells to emit fluorescence.

[0115] If the definitive diagnosis indicates that the tumor is malignant or the like and that treatment is necessary, it is preferable to inject a therapeutic drug such as a virus preparation, a plasmid preparation, a photosensitizer, or an anticancer drug into the target tissue (step 19). By using a therapeutic drug, the therapeutic effect of the treatment instrument 70 used in the subsequent process can be improved. Step 19 can be performed by inserting a drug injection instrument into the inner cavity 21 of the inner cylinder 20.

[0116] After step 19, it is preferable to irradiate the target tissue with ultrasound (step 20). This allows the therapeutic drug to easily penetrate or diffuse into the target tissue, making it possible to treat a wide area. In addition, compared to conventional treatments, the number of drug injections and the amount of drug used to achieve the same effect can be reduced.

[0117] A treatment instrument 70 is inserted into the inner cavity 21 of the inner tube 20 (step 21). For an example of the treatment instrument 70, refer to the explanation in "2. Operation method of an endoscopic treatment tool." When performing light therapy, for example, a light irradiating probe can be used as the treatment instrument 70. After step 21, it is preferable to protrude the treatment instrument 70 from the distal side of the outer tube 10 (step 22).

[0118] Treatment is performed using the treatment instrument 70 (step 23). For example, in the case of phototherapy, light is irradiated using a light irradiating probe.

[0119] This application claims the benefit of priority based on Japanese Patent Application No. 2019-148589, filed on August 13, 2019. The entire contents of the specification of Japanese Patent Application No. 2019-148589, filed on August 13, 2019, are incorporated by reference into this application. [Explanation of symbols]

[0120] 1: Endoscopic treatment tools 10: Outer cylinder 11:Lumen 20: Inner cylinder 21: lumen 23: Tapered section 24: Side hole 25: Contact part 26: Separation part 27: Small diameter section 30: Needle 31: Tip of the needle 32: Opening edge 33: Hollow part 34: Engagement part 35: Ultrasonic reflection part 35A: 1st reflection section 35B: 2nd reflection section 36: Unevenness 37: Recess 38: Convex 40: Expandable section 41: Balloon 42: Distal fixation part 43: Expansion section 44: Proximal fixation part 45:Fluid supply device 50:Operation unit 51: lumen 54: Stopper 55: First stopper 56: Second stopper 58: First check valve 59: Second check valve 61:First body cavity wall (stomach wall) 62:Second body cavity wall (pancreatic wall) 70: Treatment equipment

Claims

1. An endoscopic treatment tool to be inserted into a forceps channel of an endoscope, a barrel having a first end and a second end in a longitudinal direction and an inner cavity extending in the longitudinal direction; an inner cylinder disposed in an inner cavity of the outer cylinder, movable in the longitudinal direction relative to the outer cylinder, and having an inner cavity for supplying a fluid toward a distal side; a needle disposed in the inner cavity of the inner cylinder and movable in the longitudinal direction relative to the inner cylinder; An endoscopic treatment instrument in which, when the needle protrudes distally from the inner tube, the inner wall of the inner tube is separated from the outer wall of the needle, and the inner tube has a separation portion through which the fluid can pass.

2. The endoscopic treatment tool according to claim 1, wherein the needle can be removed from the inner cylinder in a state in which the inner cylinder protrudes distally beyond the outer cylinder.

3. The endoscopic treatment tool further includes a fluid supplier, The fluid supply device is connected to a proximal portion of the inner cylinder to supply fluid to the inner cavity of the inner cylinder; 3. The endoscopic treatment tool according to claim 1, wherein the inner cylinder has a side hole at a distal end thereof for communicating an inner cavity of the inner cylinder with the outside of the inner cylinder.

4. The endoscopic treatment tool according to claim 3, wherein the inner tube has a tapered portion whose outer diameter decreases toward a distal side of the inner tube, the tapered portion being located distal to the side hole.

5. 5. An endoscopic treatment instrument according to claim 3, wherein the inner tube has a contact portion where the inner wall of the inner tube abuts against the outer wall of the needle, and a separation portion located proximal to the contact portion and where the inner wall of the inner tube is separated from the outer wall of the needle.

6. The endoscopic treatment tool according to any one of claims 1 to 5, wherein a cross-sectional area of ​​the distal end portion of the outer tube is larger than a cross-sectional area of ​​the outer tube at a central position in a longitudinal axis direction.

7. 7. The endoscopic treatment tool according to claim 1, wherein the needle has an ultrasonic reflecting portion at a distal end thereof.

8. The endoscopic treatment tool according to claim 7 , wherein the ultrasonic reflecting portion has a first reflecting portion and a second reflecting portion located closer to the first reflecting portion.

9. The endoscopic treatment tool according to claim 8 , wherein the first reflecting portion and the second reflecting portion are projections and recesses provided on an outer surface of the needle.

10. The endoscopic treatment tool according to any one of claims 1 to 9, wherein the needle has a hollow portion at a distal portion thereof for sampling biological tissue.

11. The endoscopic treatment tool according to any one of claims 1 to 10, wherein an expandable portion is provided in a distal portion of the inner tube that is exposable from the outer tube.

12. The endoscopic treatment tool according to any one of claims 1 to 11, wherein a first stopper protruding radially outward is provided at a proximal portion of the inner cylinder.

13. The inner tube has a small diameter portion at a distal end portion, the inner diameter of which is smaller than the inner diameter at a central position in a longitudinal axis direction of the inner tube, The needle has an engagement portion having an outer diameter larger than that of the small diameter portion, The endoscopic treatment tool according to any one of claims 1 to 12, wherein the small diameter portion is located distal to the engagement portion.

14. The needle is removable from the inner cylinder, The endoscopic treatment tool according to any one of claims 1 to 13, further comprising a treatment instrument disposed in an inner cavity of the inner tube and movable in a longitudinal direction of the outer tube relative to the outer tube.

15. An endoscopic treatment tool to be inserted into a forceps channel of an endoscope, comprising: a barrel having a first end and a second end in a longitudinal direction and an inner cavity extending in the longitudinal direction; an inner cylinder disposed in an inner cavity of the outer cylinder, movable in the longitudinal direction relative to the outer cylinder, and having an inner cavity; a needle disposed in the inner cavity of the inner cylinder and movable in the longitudinal direction relative to the inner cylinder; an expandable portion provided in a portion of the distal portion of the inner tube that can be exposed from the outer tube; An endoscopic treatment instrument capable of expanding the expandable portion with the inner tube and the needle protruding from the distal side of the outer tube.

Images