Flexible radiofrequency ablation electrode guided by ultrasonic endoscope and use method of flexible radiofrequency ablation electrode

Abstract

The flexible radiofrequency ablation electrode comprises a holding handle, an electrode rod, a protective sleeve, an electrode rod control handle and a puncture needle head, the electrode rod is connected with the holding handle, the electrode rod is sleeved with the protective sleeve, the puncture needle head is arranged at the front end of the electrode rod, and the electrode rod control handle is connected with the electrode rod through a telescopic mechanism. The electrode stem can controllably contract or extend out of the sheath tube for puncturing under the action of the electrode stem control handle, a cooling mechanism is arranged in the electrode stem, and the electrode tip can be controllably cooled by the cooling mechanism. The method has the advantages that the radiofrequency ablation electrode is placed through the working clamp channel of the ultrasonic endoscope, the electrode is guided by the ultrasonic endoscope to the diseased region, and then the puncture needle is used for directly puncturing the diseased region, so that in-vitro puncture is avoided, the puncture distance is shortened, and damage to normal tissues in the puncture process is reduced; the thermocouple and the cooling mechanism are arranged, so that temperature-controlled ablation can be realized, the temperature of the needle head is controlled within 100-90 DEG C, heat injury is prevented, and the risk of postoperative pancreatitis is reduced.

Description

Technical Field

[0001] The present invention specifically relates to a flexible radiofrequency ablation electrode guided by an ultrasonic endoscope and a method of using the electrode. Background Art

[0002] Pancreatic cancer is a malignant tumor with insidious onset, rapid progression, and extremely poor efficacy and prognosis. In 2022, there were 512,000 new cases of pancreatic cancer worldwide, and it is expected to increase to 542,000 cases in 2024. In 2022, there were 118,700 new cases of pancreatic cancer in China, and 106,300 deaths.

[0003] However, as a disease with such a high incidence rate worldwide, pancreatic cancer has a 5-year survival rate of only 5% after diagnosis. For such a malignant tumor with high incidence and mortality, current traditional treatments, such as surgery, radiotherapy, chemotherapy, or a combination of these treatments, have not made any breakthrough progress. To date, radical surgical resection is still the only treatment method that is expected to cure pancreatic cancer, but only 20% of patients are eligible for surgical resection. For those patients who are not eligible for surgery, there is an urgent need for a less invasive method to increase effective treatment options.

[0004] Radiofrequency ablation (RFA) of tumors is a mature treatment method. Published literature research and expert consensus at home and abroad have shown that RFA can be used for palliative treatment of pancreatic cancer patients who cannot undergo surgery. Compared with radiotherapy and chemotherapy alone, it can improve patients' overall survival and quality of life.

[0005] However, there are currently the following problems with pancreatic ablation: (1) The pancreas lies horizontally behind the stomach, between the spleen and the duodenum. The conventional percutaneous puncture method is to puncture the pancreas directly from outside the body under a CT machine. This puncture process requires the selection of an appropriate puncture path and needle insertion point, and also requires attention to avoid important organs and tissues such as blood vessels, intestinal tract, bile duct, and pancreatic duct. The entire puncture process is time-consuming and inconvenient to use, and it will inevitably puncture other normal tissues, causing significant damage to normal tissues and increasing the risk of postoperative complications. (2) Currently, the temperature of the ablation needle tip of the radiofrequency ablation electrode is relatively high and does not have a cooling effect. Excessively high ablation temperature can cause tissue carbonization and damage, increasing the risk of postoperative pancreatitis. (3) Currently, conventional radiofrequency ablation electrodes are flexible electrodes with poor direct puncture performance; Currently, the only bile and pancreatic radiofrequency ablation electrode approved for marketing in China is BOSTON's HabibTMEndoHPB radiofrequency ablation catheter, which is 180 cm long and 7 Fr (2.7 mm) in diameter. The tip of the catheter is equipped with two ring electrodes 8 mm apart, and the distal electrode is 5 mm away from the tip of the device, forming an ablation area of ​​25 mm ± 3 mm (length) × 9 mm ± 2 mm (width). However, this product is designed only for coagulation of tissues during cavity surgeries such as the gastrointestinal tract and digestive tract (including the bile and pancreatic duct), and does not have a puncture function and cannot ablate solid, cystic, or cystic-solid pancreatic lesions.

[0006] Therefore, how to find a suitable radiofrequency ablation electrode to solve the above-mentioned problems existing in the existing ablation electrodes has become a focus of widespread concern for many front-line researchers in this field. Summary of the invention

[0007] The first technical problem to be solved by the present invention is that the existing ablation electrodes used for pancreatic radiofrequency ablation treatment mentioned in the background technology do not have puncture and cooling functions, are inconvenient to use and have poor effects.

[0008] The second technical problem to be solved by the present invention is that in the existing pancreatic radiofrequency ablation treatment process mentioned in the background technology, the existing ablation electrode puncture takes a long time, causes great damage to normal tissues and has a high risk of postoperative complications.

[0009] In order to solve the first technical problem mentioned above, a flexible radiofrequency ablation electrode guided by an ultrasonic endoscope is proposed; it is achieved by the following technical scheme: a flexible radiofrequency ablation electrode guided by an ultrasonic endoscope, comprising a holding handle, an electrode rod, a sheath tube, an electrode rod control handle and a puncture needle, the electrode rod used for ablation is connected to the holding handle, the sheath tube is sleeved on the outside of the electrode rod and connected to the holding handle, the puncture needle is arranged at the front end of the electrode rod, the electrode rod control handle is connected to the electrode rod through a telescopic mechanism, the electrode rod can be controllably retracted or extended out of the sheath tube for puncture under the action of the electrode rod control handle, and a cooling mechanism is arranged inside the electrode rod, and the cooling mechanism can controllably cool the electrode head at the end of the electrode rod.

[0010] Preferably, the electrode rod includes an electrode head, a cooling chamber and a bellows. The electrode head is arranged outside the front end of the electrode rod, and the cooling chamber is arranged at the electrode head inside the electrode rod. The circulating cooling water in the cooling chamber continuously cools the electrode head. The bellows is arranged at the end of the electrode rod, located in the holding handle. When the electrode rod is controlled to move in the sheath tube by the electrode rod control handle, the bellows expands and contracts accordingly. The arrangement of the bellows ensures that the cooling water can enter the electrode rod through the bellows for cooling, and also enables the electrode rod to expand and contract under the action of the electrode rod control handle to achieve puncture.

[0011] Preferably, the technical solution of the present invention comprises a plurality of electrodes for ablation which are spaced apart at intervals, and thermocouples for measuring the electrode temperature are arranged between the electrodes. The temperature at the electrode head is fed back through the thermocouples. The arrangement of the thermocouples facilitates real-time monitoring of the ablation temperature, reduces thermal damage to tissues, and realizes temperature-controlled ablation.

[0012] Preferably, a plurality of perfusion rings are arranged at intervals on the electrode head, and a perfusion port is provided on the perfusion ring, and the perfusion port is connected to the outside world through a perfusion tube. At the same time, the perfusion tube can be controlled to perfuse liquid into the lesion tissue to improve the tissue conductivity. The setting of the perfusion port makes it possible to perfuse liquid into the lesion tissue, improve the tissue conductivity and further reduce the needle temperature, thereby improving the ablation efficiency and reducing thermal damage.

[0013] Preferably, a circulating water pump, a conduit and a radio frequency cable are arranged in the gripping handle; the conduit includes a water inlet pipe, a water outlet pipe and an injection pipe; the water inlet pipe and the water outlet pipe for cooling water circulation are connected to the circulating water pump, the radio frequency cable for energy supply is connected to the electrode head, and the injection pipe for liquid injection is connected to the electrode head; the arrangement of the circulating water pump facilitates the circulation of cooling water to achieve heat dissipation of the electrode head.

[0014] In the preferred embodiment of the technical solution of the present invention, there are two groups of water inlet pipes and water outlet pipes. After the two groups of water inlet pipes and water outlet pipes are connected to the circulating water pump, one group is connected to the electrode head and the other group is connected to the outside world. Such an arrangement is convenient for connection with the external water supply end to realize the supply of cooling water and is easy to use.

[0015] Preferably, the telescopic mechanism includes a first gear-rack mechanism, a second gear-rack mechanism and a steering gear, wherein the first gear-rack mechanism is connected to the electrode rod control handle, the second gear-rack mechanism is connected to the electrode rod, and the first gear-rack mechanism and the second gear-rack mechanism are connected through the steering gear. The setting of the telescopic mechanism facilitates the control of the telescopic extension of the electrode rod according to the telescopic mechanism, facilitates the extension of the puncture needle for puncture, and is easy to use.

[0016] Preferably, the gear rack in the first gear rack mechanism is smaller than the gear rack in the second gear rack mechanism, and the distance the rack in the second gear rack mechanism moves is twice the distance the rack in the first gear rack mechanism moves. This arrangement allows the electrode rod control handle to move a shorter stroke, and the puncture needle can move a larger distance, which facilitates puncture.

[0017] Preferably, the puncture needle comprises a first blade surface, a second blade surface and a third blade surface for puncture, and the blade angles of the first blade surface and the second blade surface are smaller than those of the third blade surface. Such an arrangement improves the puncture ability of the puncture needle and facilitates puncturing of tissues.

[0018] In order to solve the second technical problem mentioned above, a method for using a flexible radiofrequency ablation electrode guided by an ultrasound endoscope is proposed, which is characterized in that it specifically includes puncture and ablation steps: The puncture steps include: A1. Preparation: The patient lies on his side and the end of the electrode rod is connected to the ultrasound endoscope; A2. Position guidance: insert the ultrasound endoscope through the mouth into the digestive tract and through the stomach to the pancreas; A3. Puncture: operate the electrode rod control handle, and under the action of the telescopic mechanism, the end of the electrode rod extends out from the sheath tube, and the puncture needle extends out to perform puncture; Ablation steps include: B1. After the puncture is in place, start the water cooling cycle, adjust the RF power, and start the RF output; B2. Real-time observation of the ablation status under ultrasound endoscopy to ensure the ablation effect; B3. Use the perfusion tube to perfuse liquid into the ablated tissue as needed to improve the conductivity of the tissue; B4. Based on the thermocouple feedback, monitor the ablation temperature in real time, adjust the ablation time and power, and prevent thermal damage.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The technical solution of the present invention is to insert the radiofrequency ablation electrode through the working channel of the ultrasonic endoscope, guide the electrode to the lesion site by the ultrasonic endoscope, and then use the three-edged puncture needle set at the electrode head to directly puncture the lesion site through the electrode rod control handle, thereby shortening the puncture distance, reducing puncture damage, and reducing the risk of postoperative complications; In addition, the setting of the cooling mechanism can effectively reduce thermal damage during ablation and reduce the risk of postoperative pancreatitis. The thermocouple set at the electrode head can realize real-time monitoring of the ablation temperature and reduce tissue thermal damage. At the same time, it can be matched with a radiofrequency ablation host with temperature control function to achieve temperature-controlled ablation. The needle temperature is controlled within 100℃-90℃, reducing the risk of postoperative pancreatitis. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a three-dimensional schematic diagram of the present invention; Figure 2 It is a partial cross-sectional view of the grip handle; Figure 3 It is a partial cross-sectional view of the electrode rod; Figure 4 for Figure 3 Enlarged view of point A in the middle; Figure 5 for Figure 3 Enlarged view of point B in the middle; Figure 6 It is a three-dimensional schematic diagram of the telescopic mechanism; Figure 7 It is a three-dimensional schematic diagram of the puncture needle; Figure 8 It is an exploded view of the present invention; Explanation of the reference numerals: 1-holding handle, 11-installation port, 12-circulating water pump, 13-catheter, 14-RF cable, 15-water inlet pipe, 16-water return pipe, 17-irrigation pipe, 2-electrode rod, 21-electrode head, 22-cooling chamber, 23-bellows, 24-thermocouple, 25-electrode, 26-irrigation sleeve ring, 27-cooling chamber cover, 28-irrigation port, 3-sheath tube, 31-installation ring, 32-fixing block, 4-electrode rod control handle, 41-guide ring, 42-guide hole, 5-telescopic mechanism, 51-first gear rack mechanism, 52-second gear rack mechanism, 53-steering gear, 6-puncture needle, 61-first blade surface, 62-third blade surface, 63-second blade surface, 64-connecting platform. DETAILED DESCRIPTION

[0021] The following will be combined with the attached embodiment of the present invention Figure 1-8 , the technical solutions in the embodiments of the present invention are described in detail. Example

[0022] like Figure 1 and 8 As shown, a flexible radiofrequency ablation electrode comprises a holding handle 1, an electrode rod 2, a sheath tube 3, an electrode rod control handle 4, a telescopic mechanism 5 and a puncture needle 6, wherein the puncture needle 6 is mounted on the front end of the electrode rod 2, the holding handle 1 is arranged at the other end of the electrode rod 2, the sheath tube 3 is sleeved on the outside of the electrode rod 2, and one end of the sheath tube 3 is fixed on the holding handle 1, the electrode rod control handle 4 is sleeved on the outside of the sheath tube 3, and is connected to the electrode rod 2 through the telescopic mechanism 5, and the electrode rod 2 can be controlled to extend or retract into the sheath tube 3 through the electrode rod control handle 4 and the telescopic mechanism 5.

[0023] The function of the gripping handle 1 is to facilitate the operator to hold it, and the gripping handle 1 also serves as a carrier for installing the circulating water pump 12 and the conduit 13 for supplying circulating water.

[0024] The main function of the electrode rod 2 is to serve as the main body of ablation. Radiofrequency ablation can be achieved through the electrode rod 2. In order to improve the bending performance of the electrode rod 2, the electrode rod 2 is preferably made of medical-grade PPEK material.

[0025] The main function of the sheath tube 3 is to prevent the puncture needle 6 at the head end of the electrode rod 2 from directly contacting the endoscope clamp channel, thereby protecting the endoscope clamp channel.

[0026] The main function of the electrode rod control handle 4 is to cooperate with the telescopic mechanism 5 to enable the puncture needle 6 at the head end of the electrode rod 2 to extend or retract into the sheath tube 3, so as to facilitate puncture when needed and be easy to use.

[0027] The main function of the puncture needle 6 is to provide a puncture function for the flexible electrode rod 2, so that the puncture needle 6 can be controlled by the electrode rod control handle 4 to directly puncture the lesion site, thereby facilitating the electrode head 21 at the end of the electrode rod 2 to perform radiofrequency ablation on the tissue, thereby shortening the puncture distance overall, reducing puncture damage, and reducing the risk of postoperative complications.

[0028] Definition: In this embodiment, the gripping handle 1 is taken as a reference, the gripping handle 1 is the rear end of the ablation electrode, and the corresponding end where the puncture needle 6 is installed is the front end.

[0029] like Figure 1 and 2 As shown, the gripping handle 1 is a hollow shell made of plastic, and a chamber for installing other accessories is arranged inside the gripping handle 1. The gripping handle 1 is a two-half type, that is, the two halves of the shell are connected by screws to form a complete gripping handle 1.

[0030] In order to facilitate the installation of the electrode rod 2, a circular installation opening 11 is opened at the front end of the holding handle 1, and the electrode rod 2 is inserted into the installation opening 11. A radio frequency cable 14 is passed through the holding handle 1. The radio frequency cable 14 connects the electrode rod 2 with an external control end. The electrode rod 2 can be powered by the external control end, and the power of the electrode head 21 used for ablation in the electrode rod 2 can be adjusted to achieve ablation.

[0031] In order to facilitate cooling of the ablation electrode at the head of the electrode rod 2 and prevent carbonization and damage of tissue caused by excessive temperature, a circulating water pump 12 for supplying cooling water to the cooling mechanism is also provided in the gripping handle 1. The circulating water pump 12 is an existing device and can be used directly. The circulating water pump 12 is connected to the electrode rod 2 and the external water supply bag through a catheter 13.

[0032] The catheter 13 includes an inlet pipe 15 and a return pipe 16. The inlet pipe 15 and the return pipe 16 are hollow hoses made of silicone. Their main function is to circulate the cooling liquid. In order to facilitate the connection of the inlet pipe 15 and the return pipe 16, two interfaces are respectively opened at both ends of the circulating water pump 12. The two ends of the circulating water pump 12 are respectively connected to the inlet pipe 15 and the return pipe 16. The circulating water pump 12 connects the cooling chamber 22 in the electrode rod 2 with the external water supply bag and the water collection bag through the inlet pipe 15 and the return pipe 16, so as to realize the cooling of the electrode head 21 in the electrode rod 2 and prevent the ablation temperature from being too high to cause tissue carbonization and damage.

[0033] In order to facilitate the installation of the circulating water pump 12, installation grooves are protruded inside and outside the cavity inside the gripping handle 1, and the circulating water pump 12 can be fixed in the installation groove by glue.

[0034] In order to improve tissue conductivity and ablation effect, and further enhance the reduction of tissue temperature at the ablation site, while reducing the needle temperature, improving ablation efficiency and preventing thermal damage, an irrigation tube 17 is provided in the gripping handle 1. The irrigation tube 17 is a hollow tube made of silicone. Its main function is to circulate irrigation fluid. The irrigation tube 17 passes through the gripping handle 1 to connect the irrigation collar 26 on the electrode rod 2 and the irrigation fluid storage bag. Whether the irrigation fluid is injected can be controlled through the external control end.

[0035] like Figure 2 , 3 As shown in , 4 and 5 , the electrode rod 2 includes an electrode head 21 and a bellows 23. The electrode head 21 is located at the front end of the electrode rod 2 and is sleeved on the outside of the electrode rod 2. The bellows 23 is connected to the rear end of the electrode rod 2. The electrode rod 2 is connected to the circulating water pump 12 through the bellows 23.

[0036] The electrode rod 2 is a circular hollow tube. In order to improve the bending property of the electrode rod 2 in the endoscope channel and facilitate the movement of the electrode rod 2 to a specified position, the tube body of the electrode rod 2 is made of medical-grade PPEK material.

[0037] The electrode head 21 includes a thermocouple 24, an electrode 25 and an irrigation ring 26. The electrode 25 is an existing annular electrode, and its main function is to perform radiofrequency ablation after being energized. The thermocouple 24 is annular, and its main function is to monitor the temperature at the ablation site in real time and send temperature data to the external control end to prevent excessive temperature from causing tissue carbonization and damage. The irrigation ring 26 is a circular ring, and two circular holes are provided on the arc surface of the irrigation ring 26. These circular holes are named irrigation ports 28. The irrigation tube 17 can pass through the single side wall of the electrode rod 2 and be connected to the irrigation port 28 on the irrigation ring 26. The irrigation liquid can be injected into the electrode head 21 through the irrigation tube 17 and the irrigation port 28, which can improve the tissue conductivity and improve the ablation effect, while further strengthening the reduction of the tissue temperature at the ablation site, improving the ablation efficiency and preventing thermal damage.

[0038] Regarding the position distribution of the thermocouple 24, the electrode 25 and the irrigation ring 26, the irrigation ring 26 is located between the thermocouple 24 and the electrode 25, and a thermocouple 24, an electrode 25 and an irrigation ring 26 together constitute an ablation unit. In order to improve the ablation efficiency, multiple groups of ablation units are installed on the electrode head 21. In this embodiment, three groups are preferably arranged, and the three ablation units are distributed in sequence. The ablation efficiency of the electrode head 21 can be improved by the three groups of ablation units.

[0039] Regarding the fixing method of the electrode head 21 on the electrode rod 2, the electrode head 21 can be fixed on the electrode rod 2 by existing fixing methods, and the main thing is to ensure stable fixation. In this embodiment, press-fit fixation is preferred, that is, the electrode head 21 is sleeved on the outside of the electrode rod 2 and fixed by pressure.

[0040] In order to facilitate heat dissipation of the electrode head 21, a closed chamber is provided in the electrode rod 2 at a position corresponding to the electrode head 21. This chamber is named a cooling chamber 22. Circulating cooling water can be introduced into the cooling chamber 22 through a circulating water pump 12, thereby achieving heat dissipation of the electrode head 21.

[0041] In order to facilitate the sealing of the electrode rod 2 and form a cooling cavity 22, two circular covers are fixed at the front end of the electrode rod 2. The covers are named cooling cavity covers 27. The cooling cavity covers 27 can be used to separate a closed cooling cavity 22 at the front end of the electrode rod 2.

[0042] The cooling chamber cover 27 can be fixed on the electrode rod 2 by glue or screws to ensure the tightness of the connection and prevent water leakage.

[0043] In addition, in order to facilitate the connection between the water inlet pipe 15 and the water return pipe 16 and the cooling chamber 22, a circular through hole is correspondingly opened on one of the cooling chamber covers 27. The water inlet pipe 15 and the water return pipe 16 are inserted into the cooling chamber 22 through the circular through hole, and the joints are sealed with glue. The water inlet pipe 15 and the water return pipe 16 can continuously inject circulating water into the cooling chamber 22 to cool the electrode head 21 and prevent excessive ablation.

[0044] In order to achieve perfusion, a through hole for passing the perfusion pipe 17 is also opened on the cooling chamber cover 27 that fixes the water inlet pipe 15 and the return pipe 16. The perfusion pipe 17 passes through this through hole on the cooling chamber cover 27 and is connected to the perfusion port 28 on the perfusion collar 26. This connection method can select the existing connection method. In order to ensure the sealing and prevent water leakage, the connection is sealed.

[0045] In order to allow the electrode rod 2 to be able to expand and contract in the sheath tube 3, a bellows 23 is provided at the rear end of the electrode rod 2. The main function of the bellows 23 is expansion and contraction, which facilitates the adjustment of the expansion and contraction of the electrode rod 2 in the sheath tube 3, and then realizes puncture when needed. In order to facilitate the circulation of cooling circulating water, the bellows 23 is a double-lumen tube, that is, the bellows 23 is divided into two separate chambers along the axis, and the two ends of the two chambers of the bellows 23 are respectively connected to the water inlet pipe 15, the water return pipe 16 and the circulating water pump 12 to realize the supply of circulating water.

[0046] In order to facilitate the contraction of the bellows 23, a semi-arc-shaped guide sleeve is covered on the outer cover of the bellows 23. Guided by the guide sleeve, the bellows 23 can contract along the guide sleeve after being subjected to force.

[0047] like Figure 2 , 3 As shown in FIGS. 5 and 8 , in order to prevent the electrode head 21 from directly contacting the endoscope forceps channel, a sheath tube 3 is sheathed on the outside of the electrode rod 2 , and the rear end of the sheath tube 3 is installed at the installation opening 11 on the gripping handle 1 .

[0048] The sheath tube 3 is the same as the electrode rod 2, and the tube body is also made of medical-grade PPEK material.

[0049] For the convenience of the sheath tube 3, an annular mounting ring 31 is protruded outwardly on the arc surface at the rear end of the sheath tube 3. At the same time, a mounting groove is correspondingly provided at the mounting opening 11 of the gripping handle 1. The sheath tube 3 can be clamped in the mounting groove of the gripping handle 1 through the mounting ring 31 to achieve fixation.

[0050] In order to prevent the electrode rod control handle 4 sleeved on the outside of the sheath tube 3 from interfering with the sheath tube 3, four fixing blocks 32 are protruded outwardly on the arc surface of the mounting ring 31 in the sheath tube 3. The four fixing blocks 32 are evenly distributed on the mounting ring 31, and the ends of the fixing blocks 32 are against the mounting opening 11.

[0051] like Figure 1 , 3 As shown in FIGS. 5 and 8 , the electrode rod control handle 4 is a spindle-shaped sleeve made of plastic injection molding, and its main function is to facilitate the user to hold and pull it backward to achieve the control of the extension and retraction of the electrode rod 2.

[0052] The electrode rod control handle 4 is entirely sleeved on the outside of the sheath tube 3, and the inner diameter of the electrode rod control handle 4 is the same as the outer diameter of the sheath tube 3. A circular tube protrudes outward from the rear end of the electrode rod control handle 4, and this tube is named as a guide ring 41. The electrode rod control handle 4 can move along the guide ring 41 into the gripping handle 1.

[0053] In order to avoid position interference between the guide ring 41 in the electrode rod control handle 4 and the mounting ring 31 of the sheath tube 3, four through holes penetrating the rear end of the guide ring 41 are opened on the arc surface of the guide ring 41, and the through holes are named guide holes 42. The guide holes 42 correspond to the positions of the fixing blocks 32 on the sheath tube 3. When the electrode rod control handle 4 is inserted into the holding handle 1, the electrode rod control handle 4 moves under the guidance of the guide holes 42 and the fixing blocks 32, which ensures that the electrode rod control handle 4 can move normally and avoids position interference between the guide ring 41 in the electrode rod control handle 4 and the mounting ring 31 of the sheath tube 3, thereby ensuring the stable operation of the positive device.

[0054] like Figure 6 and 8As shown, in order to facilitate the control of the electrode rod 2 to extend and retract in the sheath tube 3 through the electrode rod control handle 4, a telescopic mechanism 5 is also installed in the gripping handle 1, and the gripping handle 1 and the electrode rod 2 are connected by the telescopic mechanism 5, so as to realize the control of the extension and retraction of the electrode rod 2 in the sheath tube 3.

[0055] The telescopic mechanism 5 includes a first gear rack mechanism 51, a second gear rack mechanism 52 and a steering gear 53, wherein the first gear rack mechanism 51 is connected to the electrode rod control handle 4, the second gear rack mechanism 52 is connected to the electrode rod 2, and the steering gear 53 is fixed in the gripping handle 1 by means of mounting pins, and is located between the first gear rack mechanism 51 and the second gear rack mechanism 52, and is respectively connected to the first gear rack mechanism 51 and the second gear rack mechanism 52 to achieve adjustment of the movement direction.

[0056] The rack in the first gear-rack mechanism 51 is fixed to the guide ring of the electrode rod control handle 4 by means of screws, and the gear in the first gear-rack mechanism 51 is fixed in the holding handle 1 by means of mounting pins. When the electrode rod control handle 4 is moved inward by hand, the rack in the first gear-rack mechanism 51 can drive the gear in the first gear-rack mechanism 51 to rotate freely along the mounting pins.

[0057] The rack in the second rack and pinion mechanism 52 is fixed to the electrode rod 2 by means of screws, and the gear in the second rack and pinion mechanism 52 is fixed in the gripping handle 1 by means of mounting pins, and the gear is a double gear, wherein the larger gear meshes with the rack in the second rack and pinion mechanism 52, and the smaller gear meshes with the steering gear 53, and in addition, the steering gear 53 also meshes with the gear in the first rack and pinion mechanism 51 at the same time, so when the first rack and pinion mechanism 51 moves, it can drive the second rack and pinion mechanism 52 to move under the action of the steering gear 53.

[0058] In order to achieve an extended range of motion, that is, the electrode rod control handle 4 is inserted into the holding handle 1 for a certain distance, the electrode rod 2 moves outward from the sheath tube 3 by a distance greater than the insertion distance of the electrode rod control handle 4, and the gear rack in the first gear rack mechanism 51 is smaller than the gear rack in the second gear rack mechanism 52. In this embodiment, the distance that the rack in the second gear rack mechanism 52 moves is preferably twice the distance that the rack in the first gear rack mechanism 51 moves.

[0059] like Figure 7 and 8 As shown, in order to improve the puncture ability of the electrode rod 2, a puncture needle 6 is fixed at the front end of the electrode rod 2. The puncture needle 6 is provided with three puncture blades and a connecting platform 64. The puncture needle 6 is plugged into the front end of the electrode rod 2 through the connecting platform 64.

[0060] The puncture needle 6 is preferably made of 304 stainless steel, and has three blade surfaces, namely a first blade surface 61, a second blade surface 63 and a third blade surface 62. In order to improve the puncture effect, in this embodiment, the blade surface angles of the first blade surface 61 and the second blade surface 62 are preferably the same, and the blade surface angles of the first blade surface 61 and the second blade surface 62 are smaller than the blade surface angle of the third blade surface 63.

[0061] The connecting platform 64 is a cylindrical boss, and the outer diameter of the connecting platform 64 is the same as the inner diameter of the electrode rod 2. The puncture needle 6 is inserted into the electrode rod 2 through the connecting platform 64 and fixed with glue.

[0062] In order to improve the development effect of the puncture needle 6, a spiral reflection groove can be opened on the surface of the puncture needle 6. The reflection groove can increase the scattering of ultrasonic waves, thereby improving the development effect. The puncture needle 6 can also be coated with an existing reflective coating. In this embodiment, the two are preferably used in combination. The setting of the reflection groove and the reflective coating improves the development effect without affecting the puncture effect of the puncture needle 6.

[0063] The method for using a flexible radiofrequency ablation electrode guided by an ultrasound endoscope in this embodiment specifically includes two steps: puncture and ablation: The puncture steps include: A1. Preparation: The patient takes a side-lying position, and the end of the electrode rod 2 is connected to the ultrasonic endoscope. At the same time, the water inlet pipe 15, the water return pipe 16, the irrigation pipe 17 and the radio frequency cable 14 on the electrode rod 2 are connected to the external control end device, and the cooling, irrigation and ablation power are adjusted and controlled through the control end device; A2. Position guidance: insert the ultrasound endoscope through the mouth into the digestive tract and through the stomach to the pancreas; A3. Puncture: After reaching the designated position for puncture, the electrode rod control handle 4 is operated to move into the gripping handle 1. The movement of the electrode rod control handle 4 drives the first gear rack mechanism 51 to move. The first gear rack mechanism 51 drives the second gear rack mechanism 52 to move in the opposite direction under the action of the steering gear 53. Then, the second gear rack mechanism 52 drives the electrode rod 2 to move outward. At this time, the bellows 23 is elongated, the end of the electrode rod 2 extends from the sheath tube 3, and the puncture needle 6 extends, and puncture at the designated position can be performed. Ablation steps include: B1. After the puncture is in place, the water cooling cycle is started by using the control end device. At this time, under the action of the circulating water pump 12, circulating water is continuously poured into the cooling cavity 22. Then, the radio frequency power of the electrode head 21 is adjusted by using the control end device, and the radio frequency output is turned on to perform ablation. B2. The ablation status can be observed in real time under ultrasound endoscopy to ensure the ablation effect; B3. When it is necessary to perfuse the ablated tissue to improve the conductivity, the control end device can be used to open the perfusion tube 17, and the perfusion port 28 can be used to perfuse liquid near the ablated tissue to improve the tissue conductivity, and at the same time, the temperature of the electrode head 21 can be further reduced; B4. During the ablation process, the thermocouple 24 monitors the temperature of the ablation site in real time, and feeds back the monitored temperature to the control end device in real time. The control end device sets the stable alarm line to 100℃-90℃. When the ablation temperature exceeds 100℃, a reminder can be issued. The operator can use the control end device to adjust the ablation time and power to prevent thermal damage. When the ablation temperature is lower than 90℃, a reminder can be issued. The operator can use the control end device to adjust the ablation time and power to ensure the ablation effect.

[0064] The advantages of the structure of this embodiment are: simple structure, cooling function of the ablation electrode head, and precise control of the ablation temperature in conjunction with the thermocouple 24, effectively avoiding postoperative complications. In addition, the ablation electrode of the present invention also has a puncture function, which can directly puncture the lesion site, shorten the puncture distance, and reduce puncture damage.

[0065] Advantages of the method for using the device: The present invention adopts ultrasonic endoscope guidance, is inserted into the digestive tract through the mouth, then reaches the pancreas through the stomach, and finally uses the puncture needle 6 at the end of the electrode rod 2 to puncture the lesion position, and then ablates after reaching the designated position, shortening the puncture distance, avoiding extracorporeal puncture, reducing the difficulty of puncture, and reducing puncture damage, avoiding damage to normal tissues, and effectively preventing postoperative complications.

[0066] The above embodiments are only for illustrating the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the present invention.

Claims

1. An ultrasonic endoscope-guided flexible radiofrequency ablation electrode, characterized in that: The invention comprises a holding handle (1), an electrode rod (2), a sheath tube (3), an electrode rod control handle (4) and a puncture needle (6), wherein the electrode rod (2) for ablation is connected to the holding handle (1), the sheath tube (3) is sleeved outside the electrode rod (2) and connected to the holding handle (1), the puncture needle (6) is arranged at the front end of the electrode rod (2), the electrode rod control handle (4) is connected to the electrode rod (2) via a telescopic mechanism (5), the electrode rod (2) can be controlled to retract or extend the sheath tube (3) to perform puncture under the action of the electrode rod control handle (4), and a cooling mechanism is arranged inside the electrode rod (2), and the cooling mechanism can controllably cool the electrode head (21) at the end of the electrode rod (2).

2. The flexible radiofrequency ablation electrode guided by ultrasound endoscopy according to claim 1, characterized in that: The electrode rod (2) comprises an electrode head (21), a cooling chamber (22) and a bellows (23); the electrode head (21) is arranged outside the front end of the electrode rod (2); the cooling chamber (22) is arranged inside the electrode rod (2) at the electrode head (21); circulating cooling water in the cooling chamber (22) continuously cools the electrode head (21); the bellows (23) is arranged at the end of the electrode rod (2) and is located inside the gripping handle (1); when the electrode rod (2) is controlled to move inside the sheath tube (3) by the electrode rod control handle (4), the bellows (23) is extended and retracted accordingly.

3. The flexible radiofrequency ablation electrode guided by ultrasound endoscopy according to claim 2, characterized in that: The electrode head (21) comprises a plurality of electrodes (25) for ablation that are spaced apart from each other. Thermocouples (24) for measuring the temperature of the electrodes (25) are arranged between the electrodes (25). The temperature at the electrode head (21) is fed back via the thermocouples (24).

4. The flexible radiofrequency ablation electrode guided by ultrasound endoscopy according to claim 2, characterized in that: A plurality of perfusion rings (26) are arranged at intervals on the electrode head (21), and a perfusion port (28) is provided on the perfusion ring (26). The perfusion port (28) is connected to the outside world via a perfusion tube (17), and the perfusion tube (17) can be controlled to perfuse liquid into the lesion tissue to improve the electrical conductivity of the tissue.

5. The flexible radiofrequency ablation electrode guided by ultrasound endoscope according to claim 1, characterized in that: A circulating water pump (12), a catheter (13) and a radio frequency cable (14) are arranged in the gripping handle (1); the catheter (13) comprises a water inlet pipe (17), a water outlet pipe (18) and an irrigation pipe (17); the water inlet pipe (17) and the water outlet pipe (18) for cooling water circulation are connected to the circulating water pump (12); the radio frequency cable (14) for energy supply is connected to the electrode head (21); and the irrigation pipe (17) for liquid irrigation is connected to the electrode head (21).

6. The flexible radiofrequency ablation electrode guided by ultrasound endoscopy according to claim 5, characterized in that: There are two groups of water inlet pipes (17) and water outlet pipes (18). After the two groups of water inlet pipes (17) and water outlet pipes (18) are connected to the circulating water pump (12), one group is connected to the electrode head (21) and the other group is connected to the outside.

7. The flexible radiofrequency ablation electrode guided by ultrasound endoscopy according to claim 1, characterized in that: The telescopic mechanism (5) comprises a first gear rack mechanism (51), a second gear rack mechanism (52) and a steering gear (53); the first gear rack mechanism (51) is connected to the electrode rod control handle (4); the second gear rack mechanism (52) is connected to the electrode rod (2); and the first gear rack mechanism (51) and the second gear rack mechanism (52) are connected via the steering gear (53).

8. The flexible radiofrequency ablation electrode guided by ultrasound endoscopy according to claim 7, characterized in that: The gear rack in the first gear rack mechanism (51) is smaller than the gear rack in the second gear rack mechanism (52), and the moving distance of the rack in the second gear rack mechanism (52) is twice the moving distance of the rack in the first gear rack mechanism (51).

9. The flexible radiofrequency ablation electrode guided by ultrasound endoscopy according to claim 1, characterized in that: The puncture needle (6) comprises a first blade surface (61), a second blade surface (62) and a third blade surface (63) for puncturing, wherein the blade surface angles of the first blade surface (61) and the second blade surface (62) are smaller than that of the third blade surface (63).

10. The method for using the flexible radiofrequency ablation electrode guided by an ultrasound endoscope according to any one of claims 1 to 9, characterized in that: Specifically including puncture and ablation steps: The puncture steps include: A1. Preparation: The patient lies on his side and the end of the electrode rod (2) is connected to the ultrasound endoscope; A2. Position guidance: insert the ultrasound endoscope through the mouth into the digestive tract and through the stomach to the pancreas; A3. Puncture: operate the electrode rod control handle (4), and under the action of the telescopic mechanism (5), the end of the electrode rod (2) extends out from the sheath tube (3), and the puncture needle (6) extends to perform puncture; Ablation steps include: B1. After the puncture is in place, start the water cooling cycle, adjust the RF power, and start the RF output; B2. Real-time observation of the ablation status under ultrasound endoscopy to ensure the ablation effect; B3. Use the perfusion tube (17) to perfuse liquid into the ablated tissue as needed to improve the conductivity of the tissue; B4. Based on the feedback from the thermocouple (24), the ablation temperature is monitored in real time, and the ablation time and power are adjusted to prevent thermal damage.

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