A tissue cutting device

Abstract

This utility model discloses a tissue cutting device, including a cutting electrode and a sheath; the distal end of the sheath is provided with an insulating end tube, and the cutting electrode is axially movable through the end tube. The device is characterized by further including a sealing element for sealing the exterior of the cutting electrode, wherein the end tube is provided with a sealing groove to accommodate the sealing element. With this configuration, the exterior of the cutting electrode is well-sealed during axial movement, and liquid only flows out from the cutting electrode, ensuring both the cutting effect and safety.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, specifically to a tissue cutting device. Background Technology

[0002] Under the endoscopic view of the digestive tract, the high-frequency electrosurgical unit, which serves as a tissue cutting device, outputs high-frequency electricity from the electrode to act on the mucosal tissue, causing the mucosal tissue cells to vaporize or lose water, marking or cutting the tissue. Liquid flows out from the distal end of the electrode of the high-frequency electrosurgical unit, causing the tissue to bulge, separating the tissue to be removed from the muscle layer, making it easier to cut.

[0003] However, the sheath material commonly used in digestive endoscopy instruments is Teflon. Due to its high lubricity and stable chemical properties, Teflon sheaths are difficult to connect with other parts and cannot be stably connected through conventional bonding, heat fusion, or other processes.

[0004] Therefore, during the use of a high-frequency electrosurgical unit, unstable connections between the sheath and other components can easily lead to loosening between the electrode, ceramic tube, and sheath during axial electrode movement, affecting the cutting effect and safety. Simultaneously, when the high-frequency electrosurgical unit has fluid injection and flushing functions, loosening of the sheath and other components can also affect the electrode's sealing, causing fluid to leak out from other channels. Utility Model Content

[0005] Therefore, this invention aims to solve the problem in the prior art where unstable connection between the sheath and other parts of the electrosurgical unit can cause the high-frequency electrosurgical unit to loosen during use, and fluid to flow out from other channels, affecting the cutting effect and safety, thereby providing a tissue cutting device.

[0006] To solve the above-mentioned technical problems, the technical solution of this utility model is as follows:

[0007] This utility model provides a tissue cutting device, including a blade electrode and a sheath; the distal end of the sheath is provided with an insulating end tube, and the blade electrode is axially movable through the end tube. It also includes a sealing member for sealing the outside of the blade electrode, wherein the end tube is provided with a sealing groove for accommodating the sealing member.

[0008] Furthermore, the proximal end of the fixing member is provided with a radially outwardly extending barb structure, and the proximal end of the end tube is provided with a fixing member, the proximal end of the fixing member is provided with a radially outwardly extending barb structure, the barb structure is embedded in the inner wall of the sheath tube to form a fixed connection between the end tube and the sheath tube, so as to restrict the axial displacement of the end tube relative to the sheath tube.

[0009] Furthermore, the distal end of the end tube is provided with a sealing groove extending axially toward the proximal end of the fixing member, and the opening of the sealing groove is disposed toward the proximal end of the fixing member. The sealing member is disposed in the sealing groove and sleeved on the cutting electrode.

[0010] Furthermore, the tissue cutting device also includes a connecting tube, which is at least partially housed within the fixing member, the sheath sleeved outside the fixing member, and the connecting tube confining the seal within a sealing groove of the end tube.

[0011] Furthermore, the sealing groove is provided inside the fixing member, and a sealing groove is opened at the proximal end of the end tube, with the opening of the sealing groove facing the distal end of the end tube. The sealing member is disposed in the sealing groove and sleeved on the cutting electrode.

[0012] Furthermore, a limiting boss is provided at the distal end of the cutting head electrode, which restricts the extension position of the cutting head electrode. When the cutting head electrode is fully extended, the limiting boss remains flush with the distal end of the end tube; when the cutting head electrode is retracted, the limiting boss restricts the sealing element within the sealing groove.

[0013] Furthermore, the connecting tube is provided with a limiting boss, which restricts the extension position of the cutting electrode. When the cutting electrode is fully extended, the limiting boss is located near the end of the fixing member.

[0014] Furthermore, the end tube has a through groove extending along the length direction, and a groove is provided at the distal end of the through groove. A cutter disc is provided on the cutter electrode. When the cutter electrode is retracted to its maximum extent toward the proximal end of the sheath, the cutter disc is located in the groove, and the cutter electrode is at least partially exposed in the end tube.

[0015] Furthermore, the distal portion of the sheath has a variable diameter section, the outer diameter of which is larger than the rest of the sheath. The outer surface of the variable diameter section of the sheath is marked and located close to the end tube along the circumferential direction of the sheath; or / and, a marking ring is provided at the distal end of the variable diameter section of the sheath.

[0016] Furthermore, the tissue cutting device also includes an operating part, which includes an operating handle, an injection handle, a connector, and a finger ring, with the connector mounted on the finger ring; a protective tube is provided outside the sheath, and the proximal end of the sheath is connected to the distal end of the injection handle via barbs; a connecting tube and a torque wire are provided near the proximal end of the blade electrode, one end of the connecting tube is connected to the blade electrode, and the other end is electrically connected to the connector by welding to the torque wire; a push-pull rod is provided outside the torque wire, and the proximal end of the injection handle and the distal end of the handle are connected by a snap-fit; a sealing ring is provided between the handle and the injection handle, and a gasket is provided at the rear end of the sealing ring and abuts against the front end of the handle to apply a pressing force to the push-pull rod and the injection handle; one end of the push-pull rod passes through the gasket and the sealing ring, and the other end of the push-pull rod is fixed to the torque wire and the connector at the end face.

[0017] The technical solution of this utility model has the following advantages:

[0018] The tissue cutting device provided by this utility model has a sealing element installed inside the end tube to enhance the sealing effect on the electrode, so that liquid flows out only from the electrode channel; combined with the barbed structure of the fixing element, a fixed connection is formed between the end tube and the sheath to limit the axial displacement of the end tube relative to the sheath; with this setting, the electrode, ceramic tube and sheath are stably connected during the axial movement of the blade electrode, and will not loosen, ensuring the cutting effect and safety. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the distal portion of the tissue cutting device in an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the retracted state of the blade electrode in the tissue cutting device according to an embodiment of the present invention;

[0022] Figure 3 This is a cross-sectional view of the tissue cutting device of Embodiment 1 of this utility model with the blade electrode extended.

[0023] Figure 4 This is a cross-sectional view of the retracted state of the blade electrode in the tissue cutting device of Embodiment 1 of this utility model;

[0024] Figure 5This is a cross-sectional view of the tissue cutting device of Embodiment 2 of this utility model with the blade electrode extended.

[0025] Figure 6 This is a cross-sectional view of the retracted state of the blade electrode in the tissue cutting device of Embodiment 2 of this utility model;

[0026] Figure 7 The diagram shows the handle of the tissue cutting device according to an embodiment of this patent, along with a partially enlarged view.

[0027] Explanation of reference numerals in the attached figures:

[0028] 1. Cutter head electrode; 1-1. Cutter head disc; 2. End tube; 2-3. Groove; 3. Sheath; 3-1. Marker; 3-2. Variable diameter section; 4. Fixing component; 4-2. Barbed structure; 5. Connecting tube; 5-1. Limiting boss; 6. Torque wire; 7. Limiting boss; 8. Seal; 8-1. Sealing groove; 9. Marking ring; 10. Protective tube; 11. Injection handle; 12. Push-pull rod; 13. Gasket; 14. Sealing ring; 15. Handle; 16. Finger ring; 17. Connector. Detailed Implementation

[0029] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0030] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0032] In the embodiments of this specification, "proximal" and "distal" can refer to directions, with the side facing the operator being the "proximal" and the side facing the insertion into the body for treatment being the "distal". "Proximal" and "distal" can also refer to the part of the structure and the end located in the corresponding direction.

[0033] In the embodiments of this specification, "axial" and "radial" can refer to directions. For example, the axial direction of the protective electrode refers to the direction along the center line or rotation axis of the protective electrode, and the "radial" direction is perpendicular to the "axial" direction.

[0034] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0035] This utility model provides a tissue cutting device, including a blade electrode 1 and a sheath 3; the distal end of the sheath 3 is provided with an insulating end tube 2, and the blade electrode 1 is axially movable and passes through the end tube 2.

[0036] The blade electrode 1 can be a needle knife, hook knife, IT knife, etc. The sheath is made of Teflon, and the end tube is made of an insulating material, including but not limited to ceramic, zirconium oxide, alumina, or metal tubes with insulating sleeves or insulating coatings. The distal end of the sheath 3 has an insulating end tube, including but not limited to: the end tube is located at the distal end of the outer wall of the sheath, and the proximal end of the end tube is at least partially contained within the sheath; or the sheath 3 is sleeved over the end tube 2, and the distal end of the end tube at least partially protrudes from the distal end of the sheath.

[0037] It also includes: a sealing element 8, used to achieve sealing of the outside of the cutter electrode, wherein the end tube 2 is provided with a sealing groove 8-1 to accommodate the sealing element.

[0038] The fixing member 4 is located at the proximal end of the end tube 2. The proximal end of the fixing member has a radially outwardly extending barb structure. The barb structure is embedded in the inner wall of the sheath tube to form a fixed connection between the end tube and the sheath tube, thereby restricting the axial displacement of the end tube relative to the sheath tube. The fixing member can be integrally provided with the end tube or separately provided.

[0039] To ensure sealing performance, a sealing structure must be set up to prevent liquid leakage into non-target channels, thereby achieving a seal on the outside of the electrode.

[0040] The sealing structure includes a sealing element 8 and a sealing groove 8-1. The sealing groove 8-1 can be set inside the end tube 2, including the proximal end or the distal end of the end tube; or it can be set inside the fixing element 4, or partially set inside the end tube 2 and partially set inside the fixing element 4. The sealing element 8 is sleeved on the cutter electrode 1 and located inside the sealing groove 8-1 to achieve sealing of the outside of the cutter electrode 1.

[0041] The seal can move within the sealing groove, but its range of movement is restricted by adjacent components. When the seal is subjected to axial force, it will be restricted to abutting within the sealing groove; or the seal cannot move and is fixed within the sealing groove.

[0042] The tissue cutting device provided by this utility model has a fixing component between the sheath and the end tube, so that the end tube and the sheath are fixedly connected to limit the axial displacement of the end tube relative to the sheath. With this configuration, the electrode, ceramic tube and sheath are stably connected during the axial movement of the cutting electrode, and no loosening will occur, ensuring the cutting effect and safety. At the same time, a sealing structure is set to enhance the sealing effect of the electrode, so that the liquid flows out only from the electrode channel.

[0043] In Examples 1 and 2, the distal portion of the sheath has a variable diameter section, the outer diameter of which is larger than the rest of the sheath 3. A mark 3-1 is provided on the outer surface of the variable diameter section 3-2, positioned near the end tube 2 along the circumferential direction of the sheath. In Example 1, the mark 3-1 is made of colored ink and adhered to the outer surface of the sheath 3. The mark 3-1 can also be designed as a metal ring, for example, a stainless steel ring with a colored oxide or pigment attached to its surface.

[0044] This setup is used to determine the length of the instrument protruding under endoscopic visualization, preventing excessive protrusion that could cause perforation. The sheath 3 is diameter-adjusted, controlling the length and diameter of the variable-diameter section 3-2 to improve instrument stability within the forceps channel. Simultaneously, the height of the electrode 1 protruding from the end tube 2 is controlled to improve marking effectiveness.

[0045] Example 1:

[0046] like Figures 1-4 As shown, the end tube is located at the distal end of the outer wall of the sheath, and the proximal end of the end tube is at least partially contained within the sheath. The outer diameter of the proximal end of the end tube is smaller than the inner diameter of the distal diameter-changing section of the sheath.

[0047] The fixing component is located at the proximal end of the end tube, and the end tube and the fixing component are integrally formed. The proximal end of the fixing component 4 has a radially outwardly extending barb structure 4-2, which is embedded in the inner wall of the sheath tube 3 to restrict the axial displacement of the fixing component 4 relative to the sheath tube 3. The barb structure increases the connection force between the sheath tube and the end tube, preventing the instrument parts from loosening during the axial movement of the cutter electrode, which would affect the cutting effect and safety. The integrated end tube and fixing component design simplifies the assembly process.

[0048] A sealing groove 8-1 is provided inside the end tube 2. The end tube has a sealing groove extending axially towards the near end of the fixing member, and the opening of the sealing groove is set towards the near end of the fixing member. The sealing member is set in the sealing groove and sleeved on the cutter electrode.

[0049] The end tube is sleeved outside the seal 8. The seal can move under force within the sealing groove. When the seal is subjected to axial force, the far end of the seal 8 abuts against the far end of the end tube. Alternatively, the seal can be made immovable, with its far end abutting against the far end of the end tube.

[0050] It also includes a connecting tube 5, which is at least partially housed within the fixing member 4. The sheath 3 is sleeved outside the fixing member 4. The end tube, the fixing member, and the connecting tube 5 confine the seal within the sealing groove 8-1 of the end tube. The sheath applies a clamping force to the cutter electrode 1 and the end tube 2, while the seal 8 applies a reverse clamping force to the electrode 1 and the end tube 2, further enhancing the connection between the sheath and the end tube.

[0051] When liquid enters the sheath channel, the fluid pressure acts on the seal 8, causing the seal 8 to undergo elastic deformation under compression. The liquid pressure is converted into seal pressure, further enhancing the sealing performance. With this configuration, the seal 8 applies sealing pressure to the tip electrode 1 and the end tube, while the sheath 3 applies pressure to the tip electrode 1, the fixing element, and the end tube 2, achieving a seal on the outside of the electrode 1, i.e., sealing other channels through which the liquid flows out. The liquid is strictly confined within the electrode channel and flows out through the fluid outlet at the distal end of the tip electrode 1. This concentrated liquid energy more efficiently propels into the submucosa, forming a mucosal tissue bulge and improving surgical efficiency.

[0052] Excessive electrode protrusion from the instrument head can lead to unclear markings on the cutting blade during use. In Examples 1-3, the end tube has a through groove running along its length, with a recess 2-3 at the distal end of the through groove. A blade disc 1-1 is mounted on the blade electrode 1. When the blade electrode 1 is fully retracted towards the proximal end of the sheath 3, the blade disc 1-1 is confined within the recess 2-3, and the blade electrode 1 is at least partially exposed above the end tube 2. The height of the blade electrode 1 protruding above the end tube 2 is 0.20±0.10 mm. The smaller exposed area of ​​the blade concentrates the current, achieving hemostasis and electrocoagulation. The blade electrode can also be a column or a hook protruding radially from the outer wall of the electrode rod, etc.

[0053] To limit the length of the cutter tip extending from the end tube, the connecting tube 5 in this embodiment is provided with a limiting boss 5-1. The limiting boss 5-1 restricts the position of the cutter tip electrode 1 extending from the end tube. When the cutter tip electrode 1 is fully extended, the limiting boss 5-1 is limited to the near end of the fixing member 4. The sealing member 8 is restricted by the connecting tube 5 inside the sealing groove of the end tube 2, and the extension of the cutter tip electrode 1 is limited by the end face of the limiting boss 5-1.

[0054] Example 2:

[0055] like Figures 5-6As shown, the end tube is located at the distal end of the outer wall of the sheath, and the proximal end of the end tube is at least partially contained within the sheath. The outer diameter of the proximal end of the end tube is smaller than the inner diameter of the distal diameter-changing section of the sheath.

[0056] The fastener is located at the proximal end of the end tube, and the end tube and the fastener are integrally formed. The proximal end of the fastener 4 is provided with a radially outwardly extending barb structure 4-2. The barb structure 4-2 is embedded in the inner wall of the sheath tube 3 to limit the axial displacement of the fastener 4 relative to the sheath tube 3.

[0057] The barbed structure increases the connection between the sheath and the end tube, preventing the instrument parts from loosening during the axial movement of the cutter electrode, which would affect the cutting effect and safety. The integrated end tube and fixing design simplifies the assembly process.

[0058] A sealing groove is provided near the end of the end tube, and the opening of the sealing groove faces the far end of the end tube. The sealing groove 8-1 is located inside the fixing member 4, and the sealing member 8 is located inside the sealing groove 8-1 and sleeved on the cutter electrode. The fixing member 4 is sleeved outside the sealing member 8, and the sealing member can move within the sealing groove. When the sealing member is subjected to axial force, the near end of the sealing member 8 abuts against the inner wall of the near end of the fixing member 4; the sealing member can also be set to be immovable, with its near end abutting against the near end of the fixing member.

[0059] To limit the length of the cutter head when it extends out of the end tube, a limiting boss 7 is provided on the cutter head electrode 1. The limiting boss 7 restricts the extension position of the cutter head electrode 1. When the cutter head electrode 1 is fully extended, the limiting boss 7 is flush with the far end of the end tube. When the cutter head electrode 1 is retracted, the limiting boss 7 abuts against the far end face of the seal 8, and the limiting boss 7 restricts the seal 8 within the sealing groove.

[0060] like Figure 7 As shown, it also includes an operating unit, which includes a handle 15, an injection handle 11, a connector 17, and a ring 16, with the connector 17 disposed on the ring 16.

[0061] like Figure 7 As shown in the enlarged schematic diagram, a protective tube 10 is provided outside the sheath tube 3, and the proximal end of the sheath tube 3 is connected to the distal end of the injection handle 11 by a barb; the proximal end of the blade electrode 1 is provided with a connecting tube 5 and a torque wire 6, one end of the connecting tube 5 is connected to the blade electrode 1, and the other end is electrically connected to the connector 17 by welding to the torque wire 6, and a push-pull rod 12 is provided outside the torque wire 6.

[0062] The proximal end of the injection handle 11 is connected to the distal end of the handle 15 by a snap-fit. A sealing ring 14 is provided between the handle 15 and the injection handle 11. A gasket 13 is provided at the rear end of the sealing ring 14 and abuts against the front end of the handle 15 to apply a pressing force to the push-pull rod 12 and the injection handle 11.

[0063] One end of the push-pull rod 12 passes through the gasket 13 and the sealing ring 14, and the other end of the push-pull rod 12 is fixed to the torque wire 6 and the connector 17 at the end face. The fixing method can include, but is not limited to, welding.

[0064] The injection handle 11 and the handle 15 are fixed together by a snap fastener; at the same time, the sealing ring and the gasket are confined inside the injection handle; the sealing ring applies pressure to the push-pull rod and the injection handle respectively to achieve a seal; a gasket is provided at the rear end of the sealing ring to maintain the stability of the sealing ring shape.

[0065] This utility model is applicable not only to monopolar high-frequency electrosurgical units, but also to bipolar electrosurgical units.

[0066] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A tissue incision device comprising a blade electrode, a sheath tube; an insulating end tube is arranged at a distal end of the sheath tube, and the blade electrode is axially movably arranged in the end tube, characterized in that, Also includes: A sealing element is used to achieve a seal on the outside of the cutter electrode, wherein the end tube is provided with a sealing groove to accommodate the sealing element.

2. The tissue incision device of claim 1, wherein, The end tube has a fixing member at its proximal end, and the fixing member has a barb structure extending radially outward at its proximal end. The barb structure is embedded in the inner wall of the sheath to form a fixed connection between the end tube and the sheath, thereby limiting the axial displacement of the end tube relative to the sheath.

3. The tissue cutting device according to claim 2, characterized in that, The distal end of the end tube has a sealing groove that extends axially toward the proximal end of the fixing member, and the opening of the sealing groove is positioned toward the proximal end of the fixing member. The sealing member is disposed in the sealing groove and sleeved on the cutting electrode.

4. A tissue incision device according to claim 2 or 3, wherein It also includes a connecting tube, which is at least partially housed within the fixing member, and the sheath is sleeved outside the fixing member, the connecting tube confining the seal within the sealing groove.

5. A tissue incision device according to claim 2, wherein A sealing groove is provided at the proximal end of the end tube, and the opening of the sealing groove is set towards the distal end of the end tube. The sealing element is disposed in the sealing groove and sleeved on the cutter electrode.

6. A tissue incision device according to claim 1 or 5, wherein The distal end of the cutting electrode is provided with a limiting boss, which restricts the extension position of the cutting electrode. When the cutting electrode is fully extended, the limiting boss is flush with the distal end of the end tube. When the cutting electrode is retracted, the limiting boss restricts the seal within the sealing groove.

7. A tissue incision device according to claim 2, wherein It also includes a connecting tube, which has a limiting boss that restricts the extension position of the cutting electrode. When the cutting electrode is fully extended, the limiting boss is located near the end of the fixing member.

8. A tissue cutting device according to claim 1, characterized in that, The end tube has a through groove extending along the length direction, and a groove is provided at the distal end of the through groove. A cutter disc is provided on the cutter electrode. When the cutter electrode is retracted to its maximum extent toward the proximal end of the sheath tube, the cutter disc is located in the groove, and the cutter electrode is at least partially exposed in the end tube.

9. The tissue incision device of claim 1, wherein, The distal portion of the sheath has a variable diameter section, the outer diameter of which is larger than the rest of the sheath. The outer surface of the variable diameter section of the sheath is marked and is located close to the end tube along the circumferential direction of the sheath. or / and, A marking ring is provided at the distal end of the variable diameter section of the sheath.

10. A tissue incision device according to any one of claims 1-9, characterized in that It also includes an operating unit, which includes a handle, an injection handle, a connector, and a finger ring, with the connector disposed on the finger ring; A protective tube is provided outside the sheath, and the proximal end of the sheath is connected to the distal end of the injection handle by a barb. The cutter electrode is provided with a connecting tube and a torque wire near its proximal end. One end of the connecting tube is connected to the cutter electrode, and the other end is electrically connected to the connector by welding to the torque wire. A push-pull rod is provided outside the torque wire. The proximal end of the injection handle and the distal end of the handle are connected by a snap-fit. A sealing ring is provided between the handle and the injection handle. A gasket is provided at the rear end of the sealing ring and abuts against the front end of the handle to apply a pressing force to the push-pull rod and the injection handle. One end of the push-pull rod passes through the gasket and the sealing ring, and the other end of the push-pull rod is fixed to the torque wire and the connector at the end face.

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