Endoscopic injection equipment

Abstract

[Problem] To provide an injection tool for an endoscope, capable of maintaining a state in which a needle body is accommodated inside an outer tube, the injection tool enabling a doctor to sense operation feeling during the state of inhibiting movement and sense operation feeling at the time of releasing the accommodation state. [Solution] An injection tool 100 for an endoscope comprises: an operation part main body 4 with an outer tube 1 attached to the distal end of the operation part main body 4; and a slider 5 that is fixed to the proximal end of an inner tube 2 with a needle body 3 fixed to the distal end of the inner tube 2, wherein the slider 5 is inserted into the operation part main body 4 and slides. A second protrusion guide groove 4a for guiding a second protrusion 5e provided at the distal end of the slider 5 opens on the operation part main body 4. A locked protrusion 5e1 of the slider 5 abuts on a locking protrusion 4a1 provided in the second protrusion guide groove 4a, and the needle body is thereby prevented from protruding when the needle body is not needed. The locked protrusion 5e1 goes beyond the locking protrusion 4a1 as a result of the slider 5 being pushed into the operation part main body 4, and inhibition of movement of the slider is released.

Description

[Technical field]

[0001] The present invention relates to an endoscopic injection device that is inserted into a body cavity through a channel opened in an insertion portion of an endoscope, punctures the submucosal layer of a living body, and injects a treatment liquid. [Background technology]

[0002] In general, endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), which are used to remove the mucosa of the esophagus, stomach, large intestine, etc., involve injecting a medicinal solution such as saline or hyaluronic acid (hereafter referred to as the treatment solution) into the submucosa using an endoscopic injection tool to float the submucosa, and then removing the mucosa using a high-frequency scalpel or high-frequency snare.

[0003] The endoscopic injection device comprises a first assembly including an outer tube (sheath) inserted into a channel opened in the insertion part of the endoscope and an operation unit main body held by an operator, and a second assembly including an inner tube with a needle at its tip and a slider moved by the operator relative to the operation unit main body, the inner tube with the needle at its tip being inserted into the outer tube from the base end side of the first assembly, and configured so that the needle is protruded and retracted from the tip of the outer tube by the operator operating the slider to move forward and backward relative to the operation unit main body. The operation unit main body and the slider constitute the operation unit.

[0004] In the endoscopic injection device, the needle body is positioned within the outer tube and the operating unit body and slider are fixed relative to each other at the base end of the endoscope, with the outer tube being inserted into the channel of the insertion section, and the tip of the outer tube is guided to the affected area by video monitoring of the body cavity obtained through a lens provided at the tip of the endoscope. In this state, the endoscopic injection tool is used such that, when the operator pushes the slider into the operation unit body, the needle body is projected from the outer tube to puncture the affected area, and the treatment liquid injected from the syringe attached to the base end of the slider is injected from the needle body into the submucosal layer of the affected area (treatment). After this treatment, the operator moves the slider away from the operation unit body to store the needle body in the outer tube, and further, with the operation unit body and the slider fixed relative to each other, the operation unit is pulled out from the channel of the endoscope to separate the outer tube from the submucosal layer of the affected area. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Utility Model Application Publication No. 02-139649 [Patent Document 2] Japanese Utility Model Application Publication No. 01-68052 [Patent Document 3] JP 2020-185037 A Summary of the Invention [Problem to be solved by the invention]

[0006] It is important that the above-mentioned endoscopic injection device maintains the needle protruding from the outer tube during puncture and treatment liquid injection, and maintains the needle retracted within the outer tube at all other times.

[0007] In detail, the endoscopic injection device requires that the needle body protrudes a predetermined length from the outer tube by pushing and moving the slider toward the tip end relative to the operating unit body, and that the needle body is stored within the outer tube by pulling and moving the slider toward the base end relative to the operating unit body.

[0008] Thus, the endoscopic injection device requires that the slider be pushed into the operation section body and locked so as not to move (to keep the needle from protruding from the outer tube) before treatment until the tip of the outer tube is positioned at the affected area (submucosa of the esophagus, stomach, large intestine, etc.). If the slider is not retracted and moved toward the base end side relative to the operation section body before treatment, there is a risk that the slider and inner tube will move toward the tip side due to gravity, causing the needle to protrude from the tip of the outer tube.

[0009] More specifically, when an operator holds an endoscopic injection tool with the operation unit body on the bottom and the slider on the top, or when the operation unit body of an endoscopic injection tool is hung by a hook on the flange of the operation unit body with the operation unit body on the bottom and the slider on the top so that an operator can easily pick it up during surgery, the slider may move downward due to gravity, causing the needle to come out of the outer tube. In addition, when an endoscopic injection tool hits something, the slider may be pushed, causing the needle to come out of the sheath.

[0010] In this way, endoscopic injection devices are dangerous even before the needle is passed through the endoscope channel once it has come out of the outer tube. However, there are also problems with the needle hitting the inner surface of the channel when passing it through the endoscope channel, or accidentally piercing a part of the body cavity other than the affected area.

[0011] For this reason, there is a demand from doctors and others for an endoscopic injection device that can keep the needle protruding from the tip of the outer tube only when treatment is being performed on the affected area, and that can otherwise maintain the needle retracted within the outer tube, and that can be released by consciously pressing the retracted state.

[0012] The endoscopic injection tool described in Patent Document 1 has an inner circumferential surface of the operation section body tapered toward the tip (a shape in which the diameter of the structure is inclined toward the tip) and an outer circumferential surface of the slider also tapered, so that when the slider is pushed into the operation section body, both tapered surfaces come into contact and can be fixed by friction, thereby maintaining the needle in a protruding state. However, the endoscopic injection tool described in Patent Document 1 does not have a mechanism for maintaining the needle in a retracted state within the outer tube. Furthermore, the endoscopic injection device described in Patent Document 1 fixes the needle body protruding from the outer tube by friction between the inner surface of the operating section body and the outer surface of the slider, so there is a possibility that the needle body will not protrude sufficiently depending on the strength of the operator's (doctor or technician's) force, and it is difficult to determine the fixing position.

[0013] The endoscopic injection device described in Patent Document 2 comprises an operating section main body that opens in the longitudinal direction of the side wall and has a slide groove with multiple hook-shaped locking grooves, and an inner handle that slides within the operating section main body and has a protrusion on its side that fits into the slide groove. By sliding the protrusion along the slide groove, the needle body located at the tip of the inner handle can be slid inside the outer tube, and the position of the needle body can be locked by fitting the protrusion into the hook-shaped locking groove.

[0014] However, the endoscopic injection device described in Patent Document 2 has a problem that the operation cannot be performed smoothly because an operation such as rotating the slider is required when moving the slider protrusion from the longitudinal groove to the hook-shaped lock groove. In addition, the endoscopic injection device described in Patent Document 2 does not disclose a specific method for attaching the outer tube to the operation unit body, and when an adhesive is used for attachment, there is a problem that the adhesive deteriorates and causes a lack of safety.

[0015] The endoscopic injection device described in Patent Document 3 has a configuration in which the needle body protruding from the outer tube is releasably locked when the treatment liquid is injected after puncturing, and the doctor can feel the operation at this time, and the outer tube can be securely attached to the operating unit body.

[0016] In order to solve the above-mentioned problems, the present invention aims to provide an endoscopic injection device that not only locks the needle body protruding from the outer tube in a releasable manner during puncture and treatment liquid injection, and allows the doctor to feel the operation at this time, but also enables the needle body to be maintained and released from a state in which it is stored within the outer tube before puncture and after treatment liquid injection, and further allows the doctor to feel the operation when maintaining and releasing the stored state. [Means for solving the problem]

[0017] The injection device for an endoscope according to the present invention comprises an outer tube, an operation section main body supporting a base end of the outer tube, a needle body, an inner tube supporting a base end of the needle body, and a slider supporting a base end of the inner tube, an endoscopic injection device in which the inner tube is housed movably in the outer tube from the base end side of the operation unit body, and the tip side of the slider is housed in the operation unit body so as to be movable a predetermined stroke, and the needle body is protruded and retracted from the tip side of the outer tube by operating the slider back and forth relative to the operation unit body, and a treatment liquid is injected into the affected area from the base end of the slider when the affected area is punctured with the needle body protruded, The slider has an arm on which a projection is formed and which extends toward a tip end with elastic restoring force, The operation unit body includes a guide groove for guiding the arm of the slider in a forward and backward direction, and a base end of the guide groove. The above a locking projection that prevents the slider from moving toward the tip end by positioning the locked projection; a first state in which the locking projection and the locked projection come into contact with each other and the movement of the slider toward the tip side is prevented, to a second state in which, when the slider is moved toward the tip side, the locked projection of the slider overcomes the locking projection due to deformation caused by the elastic restoring force of the arm, thereby releasing the prevention of the movement, When the engaged projection overcomes the engaging projection, an operating sensation is generated by an increase or decrease in operating force. death, The arms are a pair of arms extending toward a tip end with an elastic restoring force, One of the pair of arms has a first projection formed at a tip end thereof, the first projection projecting in an elastic direction, and the other arm has a second projection formed at a tip end thereof, the second projection including the engaged projection, the second projection projecting in an elastic direction, The second protrusion of the other arm is fitted into the guide groove and guided in the forward and backward directions, The operation portion body has a first protrusion locking hole that is opened toward a tip end side of the guide groove and engages with the first protrusion, When the slider is moved further toward the tip end from the second state to a third state in which the first protrusion fits into the first protrusion locking hole and the needle body is locked in a state where it protrudes from the tip end of the outer tube, an operating sensation is generated by an increase or decrease in operating force. This is the first characteristic.

[0018] The present invention also provides an injection device for an endoscope according to the first aspect, The locking projections are provided on both inner sides of the guide groove in the width direction, and the locked projections are provided to protrude in the width direction of the guide groove of the second projection. The second characteristic is as follows.

[0019] The present invention also provides an injection device for an endoscope according to the second aspect, The locked projection and the locking projection are formed in a semi-spherical shape. The third characteristic is that Effect of the Invention

[0020] The object of the present invention is to provide an endoscopic injection device which can releasably lock the state in which the needle body protrudes from the outer tube during puncture and treatment liquid injection, and which allows the doctor to feel the operating sensation when this locking is activated, and which can also maintain and release the state in which the needle body is stored within the outer tube before puncture and after treatment liquid injection, allowing the doctor to feel the operating sensation when performing this locking operation, etc. [Brief description of the drawings]

[0021] [Figure 1] FIG. 2 is a plan view showing the external structure of the exploded assembly of the injection tool for an endoscope according to the embodiment of the present invention. [Diagram 2]1 shows the overall external structure of an endoscopic injection device according to an embodiment of the present invention, in which (A) is a front view showing the slider retracted toward the base end and the needle body stored within the outer tube, (B) is a diagram showing the endoscopic injection device in a state where the slider has been pushed in from the state shown in (A) and the needle body has protruded from the outer tube and rotated 180 degrees around the center line, (C) is a front view showing the slider has been pushed in from the state shown in (A) and the needle body has protruded from the outer tube, and (D) is an enlarged view of the circled portion in (A). [Diagram 3] FIG. 2A is a cross-sectional view of an endoscopic injection device according to an embodiment of the present invention, in which (A) is a cross-sectional view of the endoscopic injection device shown in FIG. 2A rotated 90 degrees to show the engagement state between the first protrusion and the first protrusion locking hole and the engagement state between the second protrusion and the second protrusion guide groove, and (B) is a cross-sectional view showing the state in which the slider is pushed in from the state shown in (A) and the needle body protrudes from the outer tube. [Figure 4] 1A and 1B are diagrams showing the operation portion main body of an endoscopic injection device according to an embodiment of the present invention, in which (A) is a cross-sectional view passing through the center line, and (B) is a view taken along the arrow BB shown in FIG. [Diagram 5] 5A and 5B are diagrams for explaining a slider of an injection tool for an endoscope according to an embodiment of the present invention, in which (A) is a front view and (B) is a view taken along the line BB shown in (A). [Figure 6] 1A and 1B are diagrams for explaining an inner guide of an injection tool for an endoscope according to an embodiment of the present invention, where (a) is a top view and (b) is a front view. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, an endoscopic treatment tool according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the side where the distal treatment section (needle body) is located in the assembled state is called the distal side, the side where the operation section is located is called the proximal side, and the direction of the line segment connecting the distal side and the proximal side is called the axial direction.

[0023] [Basic configuration] As shown in FIG. 1, which mainly shows the general appearance of the disassembled and assembled state, an endoscopic injection device 100 according to an embodiment of the present invention comprises a first assembly including a long, cylindrical outer tube 1 to be inserted into a channel of an endoscope and an operation unit main body 4 to which the outer tube 1 is attached at its tip and which is held by an operator; and a second assembly including an inner tube 2 having a needle body 3 attached to its tip and passing through the outer tube 1, an inner guide 7 (see FIG. 2A) through which the inner tube 2 passes and which is pushed into the inside of the operation unit main body 4, and a slider 5 connected to the base end side of the inner tube 2, disposed on the rear end side of the inner guide 7, and movable in the axial direction relative to the operation unit main body 4.

[0024] As shown in cross section in Figure 4(A), the operating unit main body 4 is formed in a cylindrical shape so that the inner guide 7 and slider 5 can be inserted therein, and is provided with a tip-end reduced diameter cylindrical section 4e whose diameter is reduced toward the tip end, a locking opening 4d used to lock the inner guide 7 described below at approximately the center of the cylindrical side surface, and a second protrusion guide groove 4a extending from the position of the locking opening 4d toward the base end side to guide the movement of the second protrusion 5e of the slider, details of which will be described later.

[0025] As shown in FIGS. 5(A) and 5(B), the slider 5 is formed in a generally elongated cubic shape with an opening in a tubular portion inside, has an injection port on the base end side through which treatment liquid such as physiological saline or a medicinal solution can be injected, and is provided with a first arm 5b (the first arm 5b is not shown in FIG. 1 as it is on the back side) and a second arm 5c which have elastic restoring forces and protrude radially, respectively, at diametrically symmetrical positions on the tip, and a detailed structure will be described later.

[0026] The inner guide 7, as shown in the cross section in Fig. 6, is formed in a cylindrical shape so that the inner tube 2 can be inserted therein, and is provided with a pair of locking claws 7a that are flexible and extend in a bifurcated arm shape at the base end side so as to be fitted into a pair of locking openings 4d opened on the side of the operation unit main body 4. As shown in Fig. 1, this inner guide 7 is inserted into the innermost end of the operation unit main body 4, and the tip surface abuts against the stopper 1a to hold the outer tube 1, and the locking claws 7a are fitted into the locking openings 4d of the operation unit main body 4 to be fixed to the operation unit main body 4, and a detailed structure will be described later.

[0027] In this manner, the endoscopic injection device 100 of this embodiment is configured such that the inner tube 2 is housed within the outer tube 1 and the tip side of the slider 5 is housed in the operating unit main body 4 so that it can move a predetermined stroke (the slider 5 can slide freely in the axial direction relative to the operating unit main body 4 into which the inner guide 7 is inserted), and the operating unit main body 4 and the slider 5 can be locked and unlocked relative to each other when the needle body 3 is housed within the outer tube 1.

[0028] As shown in FIG. 2(A) and FIG. 3(A), which show the state in which the slider 5 is inserted into the operation portion main body 4, the detailed structure of the injection tool for endoscope 100 is made up of the following parts. (1) An operating unit main body 4 (details are shown in FIG. 4) which is formed in a cylindrical shape for an operator to grasp, and has a tip reduced diameter cylindrical portion 4e formed by reducing the diameter of the cylinder at the tip side, a locking opening 4d opened for locking the inner guide 7, and a second protrusion guide groove 4a opened for the second protrusion 5e to slide therein for sliding the slider 5, on the bottom surface. (2) A long cylindrical outer tube 1 that is inserted through the base end opening of the operating portion main body 4, has a brim-shaped stopper 1a on the base end side, and is fixed to the operating portion main body 4 by abutting the stopper 1a against the tip reduced diameter cylindrical portion 4e of the operating portion main body 4. (3) An inner guide 7 (details are shown in FIG. 6) is inserted from the base end opening of the operation portion main body 4, and the tip side thereof abutting against the stopper 1a of the outer tube 1 is clamped by the tip reduced diameter tubular portion 4e of the operation portion main body 4, and a pair of locking claws 7a are engaged by a pair of locking openings 4d of the operation portion main body 4. (4) A slider 5 comprising a first arm 5b and a second arm 5c having an elastic restoring force with a first protrusion 5d and a second protrusion 5e protruding radially from the tip side, with approximately half of the tip side being inserted through the base end opening of the operation unit body 4, and the second protrusion 5e provided at the tip being guided by the second protrusion guide groove 4a of the operation unit body 4 and fitted in such a way that it can slide for a predetermined stroke (details are shown in Figure 5). (5) An insert pipe 6 (see FIG. 3A), the base end of which is fitted and fixed to the tip reduced diameter cylindrical portion 5a of the slider 5 and which extends to the tip side of the slider 5 up to just before the inner guide 7. (6) An inner tube 2 of a required length into which an insert pipe 6 is forcibly inserted and fixedly connected so that the inside diameter of the inner tube 2 is expanded at its base end. (7) A cylindrical needle body 3 whose tip is fixedly connected to the tip of the inner tube 2. In this application, the protrusion elastically supported on the tip side of the slider 5 is referred to as the locked protrusion, and the protrusion fixed to the operating unit body 4 that abuts against the locked protrusion and stops it is referred to as the locking protrusion.

[0029] In this endoscopic injection device 100, when the slider 5 is in the shallowest insertion state relative to the operating unit main body 4 (when the slider 5 is in a position pulled furthest toward the base end side of the operating unit main body 4), as shown in Figures 2(A) and 3(A), the base end side of the second protrusion 5e of the slider 5 abuts against the inner surface of the base end side of the second protrusion guide groove 4a of the operating unit main body 4, thereby preventing the slider 5 from falling off toward the base end side, and the locked protrusion 5e1 abuts against the locking protrusion 4a1 at a position between the base end side of the second protrusion guide groove 4a and the locking protrusion 4a1, thereby preventing the slider 5 from moving toward the tip side, and the needle body 3 is maintained in a retracted state inside the tip of the outer tube 1.

[0030] Furthermore, when the slider 5 is in the deepest fitted state relative to the operation section body 4 (when the slider 5 is in a position where it is pushed most into the operation section body 4), the endoscopic injection tool 100 according to this embodiment has the first protrusion 5d of the slider 5 fitted into the first protrusion locking hole 4c of the operation section body 4, as shown in Figures 2(B)(C) and 3(B), whereby the slider 5 and the operation section body 4 are relatively fixed and a state in which a required length portion of the needle body 3 protrudes from the tip of the outer tube 1 is maintained. Therefore, in this state, the endoscopic injection tool 100 can discharge the treatment liquid injected into the inside from the base end of the slider 5 from the inner tube 2.

[0031] In this way, the endoscopic injection device 100 of this embodiment allows the operator (doctor or technician) to sense the operating feel and engagement sound due to an increase or decrease in the operating force (the force that moves the slider 5 back and forth relative to the operating unit body 4) when the slider 5 is locked by moving to the deepest insertion position relative to the operating unit body 4, and when the lock is released to start the pull-out movement.

[0032] The configuration of each component will be described in detail below. [Outer tube 1] 3, the outer tube 1 is made of a flexible plastic material and has a long tube passage with a circular cross section, and the inner diameter of the passage is formed to be a required dimension larger than the outer diameter of the inner tube 2. The outer tube 1 also has a brim-shaped stopper 1a on the base end side, which expands in diameter in the outer circumferential direction, in order to attach it to the operation portion main body 4 described later. The outer tube 1 is made of, for example, PEEK (polyether ether ketone) resin, PTFE (polytetrafluoroethylene), or the like.

[0033] [Inner tube 2] The inner tube 2 is inserted into the outer tube 1 so as to be able to advance and retreat, and is formed in a flexible, hollow, long shape in order to deliver a treatment liquid. The inner tube 2 is made of the same material as the outer tube 1.

[0034] [Needle body 3] The needle body 3 is cylindrical, and the tip portion is cut obliquely. The outer diameter of the needle body 3 is smaller than the inner diameter of the inner tube 2. The connection strength between the needle body 3 and the inner tube 2 is maintained by fitting the connecting pipe 3a between the base end side of the needle body 3 and the tip of the inner tube 2. The needle body 3 is made of a hard metal material such as stainless steel or a hard plastic material. Since the inner diameter of the tip portion of the outer tube 1 is reduced with a step surface, even if the needle body 3 protrudes from the outer tube 1, the connecting pipe 3a cannot pass through the tip reduced diameter part of the outer tube 1 and stops by hitting the step surface of the tip reduced diameter part. Note that the connecting pipe 3a is not necessarily required, and in this case, it is necessary to configure so that the tip surface of the inner tube 2 cannot pass through the tip reduced diameter part of the outer tube 1 and hits the step surface of the tip reduced diameter part to stop.

[0035] [Operation unit 10] As shown in FIG. 2(A), the operation unit 10 is composed of a hollow operation unit body 4 and a slider 5 whose tip side is slidably and non-detachably fitted into an opening on the base end side of the operation unit body 4.

[0036] [Operation unit 4] 4(A) and (B), the operation unit body 4 is formed in a cylindrical shape having a slider accommodating hole 4f for inserting the slider 5 from the base end side, an inner guide accommodating hole 4g ​​for accommodating the inner guide 7 inside, and a tip reduced diameter cylindrical portion 4e having a reduced diameter at the tip side of the inner guide accommodating hole 4g. The operation unit body 4 has a second protrusion guide groove 4a opened to guide the second protrusion 5e of the slider 5 in the axial direction, a rib guide groove 4b engraved to guide the rib 5f provided on the slider 5 in the longitudinal direction (axial direction), a first protrusion locking hole 4c opened to fit the first protrusion 5d provided on the slider 5, and a pair of locking openings 4d opened to mount the inner guide 7 at the innermost part of the operation unit body 4.

[0037] The second projection guide groove 4a is opened in a rectangular shape of a required length on the side of the operation part main body 4, and a pair of locking projections 4a1 protruding on both inner sides in the width direction are provided near the base end (the wall on the base end side of the groove), and a position spaced a required distance from the base end opening of the operation part main body 4 is called the opening base end. The length of this second projection guide groove 4a from the base end opening of the operation part main body 4 to the opening base end is set corresponding to the dimension at which the slider 5 is fitted into the operation part main body 4 so that it can slide stably. The length of the second projection guide groove 4a is set corresponding to the stroke from the position where the needle body 3 is retracted into the outer tube 1 to the position where the joining pipe 3a approaches the tip reduced diameter part of the outer tube 1.

[0038] The rib guide groove 4b is engraved inward from the base end opening of the operating unit main body 4 on the circumferentially opposite side (inner side) of the second protrusion guide groove 4a in order to guide the rib 5f provided on the slider 5 in the longitudinal direction, and is set so that step A at the innermost end of the groove abuts step B at the tip of the rib 5f when the slider 5 is pushed all the way into the operating unit main body 4.

[0039] The first protrusion locking hole 4c is opened toward the tip side of the rib guide groove 4b so that the first protrusion 5d provided on the slider 5 fits into it when the slider 5 is pushed all the way into the operating portion main body 4 and the needle body 3 protrudes from the outer tube 1.

[0040] The pair of locking openings 4d are opened at two circumferential positions on the tip side of the first protrusion locking hole 4c in order to attach the inner guide 7 to the innermost part inside the operation portion main body 4. The pair of locking openings 4d are in the same circumferential phase (circumferential position) as the second protrusion guide groove 4a and the first protrusion locking hole 4c.

[0041] The tip reduced diameter cylindrical portion 4e is formed at the tip of the operating portion main body 4, and has an inner diameter that is just large enough to pass the outer tube 1 through but not large enough to pass the brim-shaped stopper 1a provided at the base end of the outer tube 1 through, and has an inner diameter of a length that can stably hold the required length of the base end of the outer tube 1.

[0042] [Slider 5] 5(A) and (B), the slider 5 is hollow, and its proximal opening forms an injection port into which a syringe (not shown) is connected to inject treatment fluid such as physiological saline or a drug solution, and has a distal reduced diameter tubular portion 5a on the outlet side of the injection port. An insert pipe 6 for connecting the inner tube 2 is fitted into this distal reduced diameter tubular portion 5a. The insert pipe 6 is made of stainless steel or hard plastic, and is fitted into the proximal opening of the inner tube 2 so as to expand the inner diameter of the inner tube 2, and is fixedly connected to the inner tube 2.

[0043] As shown in Fig. 5(A), the slider 5 is bifurcated at symmetrical positions in the diameter direction (circumferential direction) on the tip side to form a first arm 5b and a second arm 5c each having an elastic restoring force that allows elastic deformation in the diameter direction. As shown in Fig. 5(B), the first arm 5b has a first protrusion 5d protruding radially outward from the tip (direction in which deformation is possible due to elastic restoring force: elastic direction), and the second arm 5c has a second protrusion 5e protruding radially outward from the tip (direction in which deformation is possible due to elastic restoring force: elastic direction). When the first protrusion 5d abuts against the inner wall of the operation unit body 4, the tip of the first arm 5b elastically deforms inward due to an elastic restoring force. Also, the second protrusion 5e is provided with a pair of interlocking protrusions 5e1 protruding from the side as shown in Fig. 5(B), and abuts against the semi-spherical interlocking protrusions 4a1 of the operation unit body 4 as shown in Fig. 2(D). This prevents the slider 5 from moving the needle body 3 toward the tip side of the outer tube 1. When the slider 5 is further pushed into the operation unit body 4, the tip of the second arm 5c elastically deforms inward, and the interlocking protrusions 5e1 overcome the interlocking protrusions 4a1, thereby releasing the movement block.

[0044] As shown in FIG. 5B, the slider 5 is provided with a rib 5f that is formed in the longitudinal direction at the same circumferential position as the first protrusion 5d and closer to the base end than the first protrusion 5d.

[0045] The slider 5 is prevented from falling off from the operating unit body 4 when the second protrusion 5e comes into contact with the base end (the wall on the base end side of the groove) of the second protrusion guide groove 4a of the operating unit body 4, and the slider 5 is prevented from moving further toward the tip side when the engaged protrusion 5e1 of the slider 5 comes into contact with the engaging protrusion 4a1 of the operating unit body 4, thereby preventing the needle body 3 from protruding from the outer tube 1.

[0046] When the slider 5 is inserted deep into the base end opening of the operating unit body 4 so that the rib 5f fits into the rib guide groove 4b of the operating unit body 4, the step surface at the tip of the rib 5f abuts against the step surface 4b1 (see Figure 4) at the tip of the rib guide groove 4b of the operating unit body 4, and the second protrusion 5e engages with the second protrusion guide groove 4a provided in the operating unit body 4 and abuts against the tip side of the second protrusion guide groove 4a, thereby limiting the relative movement of the slider 5 in the pushing direction with respect to the operating unit body 4.

[0047] When the relative movement of the slider 5 in the pushing direction relative to the operation portion body 4 is restricted, the first protrusion 5d fits into the first protrusion locking hole 4c provided in the operation portion body 4 with a clicking sound due to the elastic restoring force of the first arm 5b, as shown in Fig. 3(B). This allows the operator to confirm that the slider 5 and the operation portion body 4 are locked together and that the needle body 3 has protruded from the outer tube 1 in the endoscopic injection device 100 according to this embodiment.

[0048] The first protrusion 5d protrudes in a mountain shape with its tip protruding circumferentially, and this mountain shape prevents the endoscopic injection device 100 of this embodiment from releasing the engagement (locked state) because the slope of the mountain shape hits the base end side of the first protrusion engagement hole 4c even if the operator releases his or her hand from the operating section 10. In addition, in the endoscopic injection device 100 of this embodiment, when the operator stores the needle body 3 in the inner tube 2, the slider 5 is strongly pulled in the base end direction relative to the operating unit main body 4 to disengage the first protrusion 5d from the first protrusion locking hole 4c, generating a force that pushes the first protrusion 5d inward between the mountain-shaped inclined surface of the first protrusion 5d and the first protrusion locking hole 4c, causing the first arm 5b to bend inward, and thereby causing the first protrusion 5d to sink into the operating unit main body 4 and release the engagement (locked state) with the first protrusion locking hole 4c.

[0049] The slider 5 is also restricted in its relative movement in the retracting direction with respect to the operation unit body 4. Specifically, the second protrusion 5e engages with the second protrusion guide groove 4a and abuts against the base end of the second protrusion guide groove 4a, thereby restricting the slider 5 from easily coming off from the operation unit body 4.

[0050] [Inner Guide 7] As shown in Figures 6(A) and (B), the inner guide 7 is hollow so that the inner tube 2 can be inserted therein, and has a pair of locking claws 7a that extend in two flexible arms and spread outward to fit into a pair of locking openings 4d provided in the operating unit main body 4 on the base end side.

[0051] 6(A) and 6(B), the inner guide 7 is provided with a pair of locking claws 7a for being locked by inserting its base end side into the base end opening of the operation portion main body 4 and having its tip end surface come into contact with the stopper 1a of the outer tube 1 and fitting into the locking opening 4d of the operation portion main body 4. The width dimensions of the pair of locking claws 7a and the pair of locking openings 4d are set to be larger than the width dimensions of the first protrusion locking hole 4c and the second protrusion guide groove 4a so that the pair of locking claws 7a do not erroneously fit into the first protrusion locking hole 4c or the second protrusion guide groove 4a when attaching (fitting into) the pair of locking claws 7a.

[0052] The endoscopic injection tool 100 having the above basic configuration is inserted by an operator into a channel of an endoscope (not shown) that has been inserted into a patient's body cavity in advance, with the needle body 3 in a retracted state within the outer tube 1, so that the tip side protrudes from the tip of the endoscope near the affected area. Then, when the operator pushes the slider 5 against the operation section main body 4, the first protrusion 5d of the slider 5 fits into the first protrusion locking hole 4c of the operation section main body 4, a clicking sound is generated, and the operator can confirm that the needle body 3 has protruded from the tip of the outer tube 1, and the protruding state of the needle body 3 can be maintained (see Figs. 2(B), (C), and Fig. 3(B)).

[0053] In addition, the slider 5 is prevented from moving further toward the tip side because the step surface at the tip of the rib 5f of the slider 5 contacts the step surface 4b1 at the tip of the rib guide groove 4b of the operating unit main body 4 and the second protrusion 5e of the slider 5 contacts the tip of the second protrusion guide groove 4a of the operating unit main body 4.

[0054] This endoscopic injection tool 100 is locked in a state in which the needle body 3 attached to the tip of the inner tube 2 protrudes from the tip of the outer tube 1, and the operator punctures the submucosal layer of the affected area with the needle body 3. In this state, the operator injects a treatment liquid such as physiological saline or a medicinal solution from a syringe or the like connected to the slider 5 into the submucosal layer of the affected area through the inner tube 2 and the needle body 3, lifting the submucosal layer and then excising it with a high-frequency scalpel, high-frequency snare, or the like.

[0055] [Characteristic composition] Next, a characteristic configuration of the endoscopic injection tool 100 according to the embodiment of the present invention will be described. As shown in FIGS. 2(A), (D) and 3(A), the injection tool 100 for endoscope according to this embodiment has the following functions. (1) When the slider 5 is inserted into the operating unit body 4 and the slider 5 is slidable along the guide groove (guide groove for second protrusion 4a) of the operating unit body 4 while being prevented from falling off, the hemispherical engaging protrusions 5e1 provided on the tip side of the slider 5 abut against a pair of hemispherical engaging protrusions 4a1 of the operating unit body 4 and are sandwiched between the base end edge of the guide groove for second protrusion 4a, thereby preventing the slider 5 from moving (first state) and preventing the needle body 3 from protruding from the outer tube 1.

[0056] (2) When the operator pushes the slider 5 further into the operation portion main body 4 from the first state in which the needle body 3 is prevented from protruding, the locked projection 5e1 of the slider 5 overcomes the locking projection 4a1 of the second projection guide groove 4a due to the elastic restoring force of the arm, releasing the prevention of the movement of the slider (second state), and the slider 5 slides to the back position of the second projection guide groove 4a, and the first projection 5d of the slider 5 fits into the first projection locking hole 4c of the operation portion main body 4, thereby locking the state in which the needle body 3 protrudes from the inner tube 2 (third state). The action of the locked projection 5e1 getting over the locking projection 4a1 of the second projection guide groove 4a is achieved by the locked projection 5e1, which is elastically supported by the arm, moving inward due to the elastic deformation of the second arm 5c. The aforementioned sliding can also be performed in the reverse direction, and the locking projection 4a1 and the locked projection 5e1 are preferably semi-spherical, but are not limited thereto.

[0057] In this embodiment, an example has been described in which the tip side of the slider 5 is provided with two arms that branch into two branches, one of which is used to prevent the needle from protruding, and the other arm is used to lock the needle from protruding, but the present invention is not limited to this configuration. Another example of the mechanism may be configured to provide an elastically supported locked protrusion at the tip of one arm extending from the tip of the slider, and a protrusion guide groove with locking protrusions protruding from two locations near the base end and the tip (end) side, so that the locking protrusion near the base end prevents the needle from protruding, and the locking protrusion near the tip (end) locks the needle in a protruding state.

[0058] In this embodiment, as shown in Fig. 5(B), a mechanism example is described in which the locked protrusion 5e1 protruding laterally (in the groove width direction) from the second protrusion 5e provided on the second arm 5c of the slider 5 is provided, but the mechanism according to the present invention is not limited to this configuration. Another example of the mechanism may be, for example, a structure in which a locked protrusion (elastic support protrusion) elastically supported by the slider and the operating unit main body and a fixed locking protrusion (fixed position protrusion) are provided without adopting a locked protrusion protruding laterally, and these two protrusions come into contact with each other to prevent the needle body from protruding, and further, the elastic support protrusion overcomes the fixed position protrusion to release the movement prevention by pushing the slider into the operating unit main body. The structure of the protrusion may be other structures, and for example, a structure using a combination of protrusions having inclined surfaces and arcuate curved surfaces that come into contact at an angle in the same direction is conceivable.

[0059] In this manner, in the endoscopic injection tool 100 according to this embodiment, the locked projection 5e1 is provided on the elastically deflectable second arm 5c, and the locking projection 4a1 is provided near the base end side of the second projection guide groove 4a. Therefore, the locked projection 5e1 moves over the locking projection 4a1 provided in the second projection guide groove 4a, and at this time, regardless of the direction in which the locked projection 5e1 moves, the tip side of the second arm 5c is deflected inward due to the elastic restoring force of the arm, so that the locked projection 5e1 moves inward against the locking projection 4a1 while sliding against it, thereby climbing over it. The above-mentioned overcoming is performed over an extremely small distance, and is felt by the operator as an operational feeling (click feeling) accompanied by an increase or decrease in force.

[0060] That is, in the endoscopic injection device 100 of this embodiment, the engaging projection 5e1 climbs over the engaging projection 4a1 and moves toward the base end of the second projection guide groove 4a, and the elastic return force of the second arm 5c causes the engaging projection 5e1 to move toward the tip end of the second projection guide groove 4a, and the first projection 5d of the slider 5 engages with the first projection engaging hole 4c of the operating unit main body 4, thereby entering a locked state with the needle body protruding, and the operator can feel the engagement sound during this engagement and the operating feeling due to an increase or decrease in the operating force.

[0061] As described above, the endoscopic injection device 100 with this characteristic configuration can solve the problems of the conventional technology because, when the needle body 3 is stored in the outer tube 1, the second protrusion 5e comes to the base end position of the second protrusion guide groove 4a and prevents the slider from moving. That is, even when the operation unit main body 4 is held without holding the slider 5 with the slider on the lower side and the slider on the upper side, when the operation unit main body is hung by a hook on the flange part of the operation unit main body with the operation unit main body on the lower side and the slider on the upper side so that the technician can easily take it during surgery, or when something hits the injection device in other cases, the endoscopic injection device 100 of this embodiment can solve the problems caused by the needle body 3 accidentally coming out from the tip of the outer tube 1, and can prevent the needle body from hitting a place other than the affected area even after treatment, or the needle body from hitting the inner surface of the channel when the operation unit main body 4 is pulled out of the channel of the endoscope.

[0062] Furthermore, in the endoscopic injection device 100 of this embodiment, when a predetermined force is applied to the slider 5 in the pushing direction, the engaging projections 5e1, 5e1 can move toward the tip of the slider 5 so as to overcome the engaging projections 4a1, 4a1, thereby allowing the needle body 3 to protrude from the outer tube 1 at a position corresponding to the affected area.

[0063] According to the endoscopic injection device 100 of the above embodiment, the needle body 3 is releasably locked in a protruding state from the outer tube 1 during puncture and treatment liquid injection, and the doctor can hear a clicking sound and feel an operation (clicking sensation) when locked. In addition, even when the needle body 3 is stored within the outer tube 1 before puncture and after treatment liquid injection, it is prevented from moving, and the doctor can hear a clicking sound and feel an operation (clicking sensation) when the movement is prevented and when it is released. [Explanation of symbols]

[0064] 1…Outer tube 1a…Stopper 2…Inner tube 3...Needle body 3a…Connecting pipe 4. Control unit 4a…Guide groove for second protrusion 4a1…Latching protrusion 4b…Rib guide groove 4b1…Step surface 4c…Locking hole for first protrusion 4d…Lock opening 4e…Tip diameter reducing cylinder part 4f...Slider receiving hole 4g…Inner guide housing hole 5...Slider 5a…Tip diameter reducing cylinder part 5b…First arm 5c…Second arm 5d…1st protrusion 5e…Second protrusion 5e1…Locked protrusion 5f…Rib 5f1…Step surface 6…Insert pipe 7…Inner guide 7a…Lock claw 10...Operation unit 100...Injection device for endoscope

Claims

1. an outer tube, an operation unit main body supporting a base end of the outer tube, a needle body, an inner tube supporting a base end of the needle body, and a slider supporting a base end of the inner tube; an endoscopic injection device in which the inner tube is housed movably in the outer tube from the base end side of the operation unit body, and the tip side of the slider is housed in the operation unit body so as to be movable a predetermined stroke, and the needle body is protruded and retracted from the tip side of the outer tube by operating the slider back and forth relative to the operation unit body, and a treatment liquid is injected into the affected area from the base end of the slider when the affected area is punctured with the needle body protruded, The slider has an arm on which a projection is formed and which extends toward a tip end with elastic restoring force, the operation portion body has a guide groove for guiding the arm of the slider in an advancing / retreating direction, and a locking projection provided on a base end side of the guide groove and for preventing movement of the slider toward a tip end side by positioning the locked projection between the base end of the guide groove and the locking projection, a first state in which the locking projection and the locked projection come into contact with each other and the movement of the slider toward the tip side is prevented, to a second state in which, when the slider is moved toward the tip side, the locked projection of the slider overcomes the locking projection due to deformation caused by the elastic restoring force of the arm, thereby releasing the prevention of the movement, When the engaged projection overcomes the engaging projection, an operating sensation is generated due to an increase or decrease in operating force, The arms are a pair of arms extending toward a tip end with an elastic restoring force, One of the pair of arms has a first projection formed at a tip end thereof, the first projection projecting in an elastic direction, and the other arm has a second projection formed at a tip end thereof, the second projection including the engaged projection, the second projection projecting in an elastic direction, The second protrusion of the other arm is fitted into the guide groove and guided in the forward and backward directions, the operation portion body has a first protrusion locking hole that is opened toward a tip end side of the guide groove and engages with the first protrusion, An endoscopic injection device that generates a sense of operation due to an increase or decrease in operating force when the slider is moved further toward the tip from the second state to a third state in which the first protrusion engages with the first protrusion locking hole and locks the needle body protruding from the tip of the outer tube.

2. The locking projections are provided on both inner surfaces of the guide groove in the width direction, The injection tool for an endoscope according to claim 1 , wherein the interlocking projection is provided so as to protrude in a width direction of the guide groove of the second projection.

3. The injection tool for an endoscope according to claim 2 , wherein the locked projection and the locking projection are formed in a semi-spherical shape.

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