Loop adjuster for a snare

Abstract

The application discloses a loop-adjustable snare, and belongs to the technical field of medical devices; the loop-adjustable snare comprises a loop, an outer tube, an inner tube, a cable, a slip ring and a handle, wherein the loop is made of a shape memory alloy, both ends of the loop root are connected with electrified wires, and the two electrified wires are spirally wound on the cable along the length direction of the cable; a MEMS pressure sensor for tension monitoring is arranged between the loop root and the cable, and the signal wire of the MEMS pressure sensor is spirally wound on the cable along the length direction of the cable; a connector is arranged on the slip ring, the electrified wires and the signal wire are electrically connected with the connector respectively, and the connector is used for being connected with an external circuit; the shape of the loop and the opening width can be adjusted according to different sizes and shapes of polyps, meanwhile, the tension of the loop when being tightened is monitored in real time by using the MEMS pressure sensor, so that the safety in the operation process is improved, and the tissue is prevented from being torn or bleeding due to the excessive tightening of the loop.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to an adjustable snare device. Background Technology

[0002] A snare is a surgical instrument that uses a metal snare to mechanically tighten, allowing for procedures such as ligating blood vessels, removing polyps or other diseased tissues, and capturing and removing foreign objects from the body. Traditional snares have the following limitations in use: (1) The shape and width of the ring are fixed, making it difficult to match polyps with complex shapes; (2) The tension of the ring cannot be monitored in real time during operation. The operator tightens the ring based on experience, which can easily lead to tissue tearing or bleeding due to over-tightening. (3) The tube and the ring lack imaging markers, and the intraoperative positioning depends on the endoscopic field of view. When encountering complex areas, blind spots are likely to occur. Summary of the Invention

[0003] To address the limitations of traditional snare devices in use, this invention provides an adjustable snare device.

[0004] The technical solution of this invention is as follows: An adjustable snare includes a snare, an outer tube, an inner tube, a cable, a slip ring, and a handle. The outer tube is connected to the handle to provide support and guidance. The inner tube is disposed in the outer tube and connected to the slip ring to accommodate the cable. The cable is located in the inner tube, with one end connected to the snare and the other end connected to the slip ring. The slip ring is slidably disposed on the handle. The collar is made of shape memory alloy. The two ends of the collar root are connected to a live wire, and the two live wires are spirally wound around the cable along the length of the cable. A MEMS pressure sensor for tension monitoring is provided between the root of the collar and the cable, and the signal wire of the MEMS pressure sensor is spirally wound on the cable along the length of the cable. A connector is provided on the slip ring, and the power-conducting wire and the signal wire are electrically connected to the connector respectively. The connector is used to connect to an external circuit.

[0005] In order to adjust the shape and width of the ring to adapt to complex polyp morphology, the ring made of shape memory alloy of the present invention includes a temporary form and a preset form, and the width of the preset form is larger than that of the temporary form. An energizing device is provided in the external circuit. The energizing device is used to energize the ring made of shape memory alloy. When the ring made of shape memory alloy is heated to the Af temperature by the energizing device, it changes from the temporary form to the preset form.

[0006] As a preferred embodiment of the present invention, a tension controller is provided in the external circuit. The tension controller is electrically connected to the MEMS pressure sensor and has a display for displaying the tension value monitored by the MEMS pressure sensor. The MEMS pressure sensor can monitor the tension when the ring is tightened in real time. The display can show the monitored tension in digital and graphical form so that the operator can know the tension when the ring is tightened, thus preventing tissue tearing or bleeding caused by excessive tightening of the ring.

[0007] To alert the operator when excessive tension is applied during tightening of the ring, the tension controller is electrically connected to an alarm device. The tension controller can set a tension threshold. When the tension value detected by the MEMS pressure sensor exceeds the tension threshold set by the tension controller, the tension controller controls the alarm device to sound an alarm.

[0008] As a preferred embodiment of the present invention, the alarm device includes an audible and visual alarm and a micro vibrator. The audible and visual alarm is mounted on the tension controller to provide an audible and visual alarm, which may be a buzzer and a red LED light. The micro vibrator is mounted on the slip ring to provide vibration feedback. Under the action of vibration feedback, it can better remind the operator that the tightening tension of the ring exceeds the set tension threshold. By embedding the micro vibrator in the slip ring, the vibration generated by the micro vibrator is transmitted to the slip ring, and the operator's fingers can feel the vibration more directly. When the operator's fingers feel the vibration on the slip ring, the operator's fingers can quickly adjust the force to reduce the tightening tension of the ring.

[0009] As a preferred embodiment of the present invention, a circular ring is provided at the root of the collar, the MEMS pressure sensor is fixed inside the circular ring, and a connecting ring is provided at the front end of the cable, the connecting ring being interlocked with the circular ring; this achieves accurate measurement of tension when the collar is tightened, as the cable is pulled backward, and ensures efficient transmission of thrust when the collar is released, as the cable is pushed forward; thus, the connection between the collar, the MEMS pressure sensor, and the cable achieves both functionality and reliability.

[0010] Furthermore, the surface of the MEMS pressure sensor is covered with medical-grade flexible epoxy resin adhesive, and a window without medical-grade flexible epoxy resin adhesive is reserved in the sensitive area of ​​the MEMS pressure sensor. Using medical-grade flexible epoxy resin adhesive to wrap the MEMS pressure sensor can protect electronic components and improve the waterproof rating. Its hardness is close to that of biological tissue, avoiding stress dispersion due to excessive material rigidity.

[0011] Furthermore, there is a movable gap between the connecting ring and the circular ring, and the movable gap is 0.1mm; this allows the connecting ring and the circular ring to move relative to each other, but the range of movement is limited, so as to avoid affecting the action of the cable when pushing and pulling the loop; the connecting ring has micro protrusions that correspond to and cooperate with the sensitive area of ​​the MEMS pressure sensor; this ensures that the force is directly applied to the sensitive area of ​​the MEMS pressure sensor.

[0012] As a preferred embodiment of the present invention, the inner tube has strip-shaped imaging marks embedded in its wall, extending along its length, and annular imaging marks are arranged at equal intervals. The strip-shaped and annular imaging marks work together to improve imaging effect and facilitate precise positioning under X-ray or endoscopic imaging. At the same time, since the inner and outer tubes are usually made of transparent materials to facilitate inspection of the cables in the inner tube before use, the strip-shaped and annular imaging marks do not affect the operator's inspection of the cables in the inner tube before use. Compared with other traditional medical devices that have a full-coverage imaging layer in the tube body, the present invention achieves both imaging effect and ensures the transparency of the inner tube.

[0013] As a preferred embodiment of the present invention, at least four developing alloy points are welded on the collar; the developing alloy points are made of platinum-iridium alloy, and multiple developing alloy points can improve the developing effect of the collar under X-ray, making the outline of the collar clearly visible under X-ray, which makes it easier for the operator to determine the shape of the collar and to accurately position it when operating the collar.

[0014] The advantages of this invention are: (1) The ring is made of shape memory alloy and has two forms, so that the shape and width of the ring can be adjusted according to the different sizes and shapes of the polyps; (2) The tension of the collar is monitored in real time by using a MEMS pressure sensor. When the tension value monitored by the MEMS pressure sensor is greater than the tension threshold set by the tension controller, the tension controller controls the alarm device to sound an alarm, thereby preventing tissue tearing or bleeding caused by excessive tightening of the collar and improving the safety of the operation. (3) The present invention innovatively designs an interlocking structure at the connection of the collar, MEMS pressure sensor and cable, so as to achieve both functionality and reliability at the connection of the collar, MEMS pressure sensor and cable. (4) The present invention embeds strip-shaped imaging marks and ring-shaped imaging marks in the tube wall of the inner tube. Compared with the traditional medical device that sets a full-coverage imaging layer in the tube body, the present invention achieves imaging effect and ensures the transparency of the inner tube. (5) The present invention welds multiple developing alloy points on the ring. Multiple developing alloy points can improve the developing effect of the ring under X-ray, making the outline of the ring clearly visible under X-ray, which makes it easier for the operator to determine the shape of the ring and to accurately position it when operating the ring. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure after the release of the ring of the present invention. Figure 1 The ring toss is a temporary form; Figure 2 This is a schematic diagram of the structure after the release of the ring of the present invention. Figure 2 The ring toss is a preset shape; Figure 3 This is a schematic diagram of the structure of the collar part of the present invention; Figure 4 yes Figure 3 Enlarged diagram of point A in the diagram; Figure 5 yes Figure 3 An enlarged schematic diagram of point A in the diagram, with the circular ring showing a cross-section; Figure 6 This is a schematic diagram of the collar structure of the present invention; Figure 7 This is a circuit connection framework diagram of the present invention; Figure 8 This is a schematic diagram of the developing mark on the inner tube of the present invention.

[0016] Meaning of the reference numerals in the diagram: 1-Ling ring, 2-Outer tube, 3-Inner tube, 4-Cable, 5-Slip ring, 6-Handle, 7-Limit block; 8 - MEMS pressure sensor; 9 - Signal wire; 10 - Power-carrying wire; 11-Connector, 12-Developable alloy dot, 13-Miniature vibrator, 20-Miniature bump; 21-Circular ring, 22-Connecting ring, 30-Circular development mark, 31-Strip development mark. Detailed Implementation

[0017] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0018] like Figure 1 and 2 As shown, this embodiment is an adjustable snare, including a snare 1, an outer tube 2, an inner tube 3, a cable 4, a slip ring 5, and a handle 6. The outer tube 2 is connected to the handle 6 to provide support and guidance. The inner tube 3 is disposed in the outer tube 2 and connected to the slip ring 5 to accommodate the cable 4. The cable 4 is located in the inner tube 3, with one end connected to the snare 1 and the other end connected to the slip ring 5. The slip ring 5 is slidably disposed on the handle 6. By operating the cable 4 through the slip ring 5, the snare 1 is pushed out of the outer tube 2 to release or retract into the outer tube 2 to tighten. A limit block 7 is usually also provided on the handle 6 for limiting. The above is the prior art and will not be described in detail here.

[0019] like Figure 1-5As shown, in this embodiment, the collar 1 is made of shape memory alloy. The two ends of the collar 1, which is made of shape memory alloy, are respectively connected to the power-carrying wires 10. The two power-carrying wires 10 are spirally wound on the cable 4 along the length direction of the cable 4. A MEMS pressure sensor 8 for tension monitoring is provided between the base of the collar 1 and the cable 4. The signal wire 9 of the MEMS pressure sensor 8 is spirally wound on the cable 4 along the length direction of the cable 4. A connector 11 is provided on the slip ring 5. The power-carrying wires 10 and the signal wires 9 are electrically connected to the connector 11, which is used to connect to an external circuit. The power-carrying wires 10 and the signal wires 9 are made of silver-plated copper wire and are covered with a polytetrafluoroethylene insulation layer or a polyimide insulation layer.

[0020] To adjust the shape and width of the collar 1 to adapt to complex polyp morphologies, the collar 1 made of shape memory alloy in this embodiment includes a temporary form and a preset form, with the width of the preset form being larger than that of the temporary form. An energizing device is provided in the external circuit to energize the collar 1 made of shape memory alloy. When the collar 1 made of shape memory alloy is energized, the current will cause a resistance heating effect in the material, causing its temperature to rise. When the collar 1 made of shape memory alloy is heated to temperature Af by the energizing device, it changes from the temporary form to the preset form. The temperature Af of the collar 1 made of shape memory alloy is designed to be 45±2℃ to meet the shape recovery requirements under body temperature conditions.

[0021] like Figure 1 and 2 As shown, in this embodiment, the temporary shape of the ring 1 made of shape memory alloy is hexagonal, and the preset shape is elliptical. Of course, in practical applications, the temporary shape can also be designed as crescent-shaped, and the preset shape as circular. In use, the smaller polyp is first encased in the temporary shape of the ring 1 with a smaller opening. After the smaller polyp is processed, the ring 1 is energized by the energizing device. When the ring 1 is heated to temperature Af by the energizing device, the ring 1 changes from the temporary shape with a smaller opening to the preset shape with a larger opening. Then, the larger polyp is encased in the preset shape with a larger opening. Thus, the shape and opening of the ring 1 can be adjusted according to the different sizes and shapes of the polyps.

[0022] like Figure 7As shown, in this embodiment, a tension controller is set in the external circuit. The tension controller is electrically connected to the MEMS pressure sensor 8. The tension controller is equipped with a display, which is used to display the tension value monitored by the MEMS pressure sensor 8. The MEMS pressure sensor 8 can monitor the tension of the collar 1 in real time when it is tightened. The display can show the monitored tension in digital and / or graphical form so that the operator can know the tension of the collar 1 when it is tightened, and prevent tissue tearing or bleeding caused by excessive tightening of the collar 1. The display is a touch screen display, so as to facilitate operation and information input of the tension controller through the touch screen display. The tension controller uses a microcontroller MCU-STM32 series.

[0023] In this embodiment, to alert the operator when the tension of the collar 1 is too high, the tension controller is also electrically connected to an alarm device. The tension controller can set a tension threshold. When the tension value detected by the MEMS pressure sensor 8 exceeds the tension threshold set by the tension controller, the tension controller controls the alarm device to sound an alarm. The alarm device includes an audible and visual alarm and a micro vibrator 13. The audible and visual alarm is located on the tension controller and is used to provide audible and visual alarms. The audible and visual alarm uses a buzzer and a red LED light. The micro vibrator 13 is located on the slip ring 5 and is used to provide vibration feedback. The micro vibrator 13 is connected to an external circuit through the connector 11 on the slip ring 5. Under the action of vibration feedback, it can better remind the operator that the tension of the collar 1 exceeds the set tension threshold. By embedding the micro vibrator 13 in the slip ring 5, the vibration generated by the micro vibrator 13 is transmitted to the slip ring 5, and the operator's fingers feel the vibration more directly. When the operator's fingers feel the vibration on the slip ring 5, the operator's fingers can quickly adjust the force to reduce the tension of the collar 1.

[0024] like Figure 3-5 As shown, in this embodiment, a ring 21 is set at the root of the collar 1. The power-carrying wire 10 connected to the collar 1 passes through the ring body of the ring 21. The MEMS pressure sensor 8 is fixed inside the ring 21. The signal wire 9 of the MEMS pressure sensor 8 passes through the ring body of the ring 21. A connecting ring 22 is set at the front end of the cable 4. The connecting ring 22 is interlocked with the ring 21. This realizes the accurate measurement of tension when the collar 1 is tightened, the cable 4 is pulled backward, and the efficient transmission of thrust is ensured when the collar 1 is released. Thus, the connection between the collar 1, the MEMS pressure sensor 8, and the cable 4 takes into account both functionality and reliability. The surface of the MEMS pressure sensor 8 is covered with medical-grade flexible epoxy resin (not shown in the figure), and a window without medical-grade flexible epoxy resin is reserved in the sensitive area of ​​the MEMS pressure sensor 8. The use of medical-grade flexible epoxy resin to wrap the MEMS pressure sensor 8 can protect electronic components and improve the waterproof level. Its hardness is close to that of biological tissue.

[0025] In this embodiment, there is a movable gap between the connecting ring 22 and the circular ring 21, and the movable gap is 0.1mm; this allows the connecting ring 22 and the circular ring 21 to move relative to each other, but the range of movement is limited to avoid affecting the action of the cable 4 when pushing and pulling the collar 1; for example Figure 5 As shown, micro protrusions 20 are formed on the connecting ring 22 to correspond to the sensitive area of ​​the MEMS pressure sensor 8; when tightening the collar 1, the micro protrusions 20 press the sensitive area of ​​the MEMS pressure sensor 8, thereby ensuring that the force is directly applied to the sensitive area of ​​the MEMS pressure sensor 8.

[0026] like Figure 6 As shown, in this embodiment, eight developing alloy points 12 are welded onto the collar 1. The eight developing alloy points 12 are arranged at intervals. The developing alloy points 12 are made of platinum-iridium alloy. The eight developing alloy points 12 can improve the developing effect of the collar 1 under X-ray, making the outline of the collar 1 clearly visible under X-ray, which makes it easier for the operator to determine the shape of the collar 1 and to accurately position it when operating the collar 1. In actual application, the number of developing alloy points 12 welded onto the collar 1 can be appropriately increased or decreased, but it should be at least four.

[0027] In another embodiment of this invention, strip-shaped development marks 31 extending along the length of the inner tube 3 are embedded in the wall of the inner tube 3, and annular development marks 30 are provided at equal intervals, such as... Figure 8 As shown; the bar-shaped imaging mark 31 and the ring-shaped imaging mark 30 are barium sulfate imaging lines. The bar-shaped imaging mark 31 and the ring-shaped imaging mark 30 work together to improve the imaging effect and facilitate accurate positioning under X-ray or endoscopic imaging. At the same time, since the inner tube 3 and the outer tube 2 are usually made of transparent material to facilitate the inspection of the pull cable 4 before use, the bar-shaped imaging mark 31 and the ring-shaped imaging mark 30 do not affect the operator's inspection of the pull cable 4 before use. Compared with the traditional medical device method of setting a full-coverage imaging layer in the tube body, this embodiment achieves imaging effect while ensuring the transparency of the inner tube 3.

[0028] This embodiment is applicable to endoscopic polyp removal. In use, the snare is inserted through the endoscope forceps channel and located to the polyp using the endoscope and contrast markers. The slip ring 5 is pushed to release the snare 1 and make the snare 1 fit around the base of the polyp. The snare 1 is slowly tightened while paying attention to the tension of the snare 1 to ensure that the tension of the snare 1 does not exceed the set tension threshold. If the operator sees the red LED light up, hears the buzzer, or feels vibration on the slip ring 5, the operator should quickly adjust the force to reduce the tension of the snare 1. After the tension stabilizes, the snare 1 is fully tightened and the polyp is removed. This operation is repeated until all polyps are removed, and finally the snare is withdrawn.

[0029] During the polyp removal process, the smaller polyp is first encircled in a temporary form with a smaller opening, called a lasso 1. After the smaller polyp is removed, the lasso 1 is energized by an energizing device, causing it to change from the temporary form with a smaller opening to a preset form with a larger opening. The larger polyp is then encircled in the preset form with the larger opening.

[0030] Operational Example 1: Broad-based polyp removal After release, ring 1 is a temporary hexagonal shape with an opening d of 25mm, as shown below. Figure 1 As shown; the tension threshold is set to 18N; After the loop 1 completely encloses the polyp, the tension stabilizes at 16N when tightened, and the removal is successfully completed.

[0031] Operational Example 2: Removal of a large pedunculated polyp Switch the ring 1 configuration so that after release, ring 1 is an oval shape with a width d of 35mm, as shown. Figure 2 As shown; the tension threshold is set to 20N; After the loop 1 completely wrapped the polyp, the tension stabilized at 17N when tightened, and the polyp was successfully removed.

[0032] This embodiment can significantly improve surgical precision, safety, and operational efficiency, and is applicable to various endoscopic gastrointestinal polyp removal scenarios.

[0033] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention 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. Therefore, they should not be construed as limitations on this invention.

[0034] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "setting," and "forming" should be interpreted broadly; for example, they can refer to fixed connections or settings, detachable connections or settings, or integrated structures; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium, or internal connections between two components; those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0035] The above embodiments are only used to illustrate the technical solutions of the present invention. Those skilled in the art should understand that the above embodiments do not limit the present invention in any way. All technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of the present invention.

Claims

1. An adjustable snare, comprising a snare, an outer tube, an inner tube, a cable, a slip ring, and a handle, wherein the outer tube is connected to the handle for providing support and guidance, the inner tube is disposed within the outer tube and connected to the slip ring for accommodating the cable, the cable is located within the inner tube, one end of the cable is connected to the snare, and the other end is connected to the slip ring, the slip ring being slidably disposed on the handle, characterized in that: The collar is made of shape memory alloy. The two ends of the collar root are connected to a live wire, and the two live wires are spirally wound around the cable along the length of the cable. A MEMS pressure sensor for tension monitoring is installed between the base of the collar and the cable. The signal wire of the MEMS pressure sensor is spirally wound around the cable along its length. A circular ring is provided at the base of the collar, and the MEMS pressure sensor is fixed inside the circular ring. A connecting ring is provided at the front end of the cable, and the connecting ring interlocks with the circular ring. The surface of the MEMS pressure sensor is covered with medical-grade flexible epoxy resin, and a window without medical-grade flexible epoxy resin is reserved in the sensitive area of ​​the MEMS pressure sensor. There is a movable gap of 0.1 mm between the connecting ring and the circular ring. Micro-protrusions are formed on the connecting ring that correspond to the sensitive area of ​​the MEMS pressure sensor. A connector is provided on the slip ring, and the power-conducting wire and the signal wire are electrically connected to the connector respectively. The connector is used to connect to an external circuit.

2. The adjustable ring snare according to claim 1, characterized in that, The shape memory alloy ring includes a temporary form and a preset form, and the opening of the preset form is larger than that of the temporary form. An energizing device is provided in the external circuit. The energizing device is used to energize the shape memory alloy ring. When the shape memory alloy ring is heated to temperature Af by the energizing device, it changes from the temporary form to the preset form.

3. The adjustable ring snare according to claim 1, characterized in that, The external circuit includes a tension controller, which is electrically connected to the MEMS pressure sensor. The tension controller also includes a display for showing the tension value detected by the MEMS pressure sensor.

4. The adjustable ring snare according to claim 3, characterized in that, The tension controller is electrically connected to an alarm device. The tension controller can set a tension threshold. When the tension value detected by the MEMS pressure sensor is greater than the tension threshold set by the tension controller, the tension controller controls the alarm device to sound an alarm.

5. The adjustable ring snare according to claim 4, characterized in that, The alarm device includes an audible and visual alarm and a miniature vibrator. The audible and visual alarm is mounted on the tension controller to provide audible and visual alarm, and the miniature vibrator is mounted on the slip ring to provide vibration feedback.

6. The adjustable ring snare according to claim 1, characterized in that, The inner tube has strip-shaped development marks embedded in its wall, extending along the length of the inner tube, and annular development marks are set at equal intervals.

7. An adjustable snare device according to any one of claims 1-6, characterized in that, At least four developing alloy points are welded onto the collar.

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