A radiofrequency ablation electrode

Abstract

The present invention discloses a radiofrequency ablation electrode, which relates to the technical field of medical devices and includes a working end. The working end comprises a main working electrode and a secondary working electrode arranged coaxially. The main working electrode and the secondary working electrode are separated by an insulating device arranged coaxially, and the axial distance between the main working electrode and the secondary working electrode can be adjusted. The two poles of a radiofrequency generator are respectively connected to the main working electrode and the secondary working electrode through radiofrequency wires. A cooling system can introduce a circulating refrigerant medium into the inner channels of the main working electrode and the secondary working electrode. The micro-permeation structure includes permeation openings respectively formed on the side walls of the main working electrode and the secondary working electrode. The permeation opening on the main working electrode is communicated with the inner channel, and the permeation opening on the secondary working electrode is communicated with the permeation channel of the secondary working electrode. A part of the refrigerant medium flowing back from the cooling system can enter the permeation channel. In the present invention, both the main working electrode and the secondary working electrode have independent micro-permeation structures, which can avoid the problems of serious tissue carbonization and limited ablation range during the ablation process.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a radio frequency ablation electrode. Background Art

[0002] With the gradual maturity of various ablation techniques, minimally invasive ablation techniques such as microwave ablation, radiofrequency ablation and cryoablation have achieved good clinical feedback in the treatment of diseases such as gastrointestinal tumors, solid tumors of the liver, lung, kidney, prostate hyperplasia, benign thyroid nodules, etc.

[0003] Radiofrequency ablation technology is widely used in situations where precise ablation is required due to its safety and controllability. According to the working end structure, radiofrequency ablation electrode consumables can be divided into monopolar electrodes and bipolar electrodes. The monopolar electrode needs to be combined with a neutral electrode sheet to form a current loop. The neutral electrode sheet needs to be attached to the patient's muscles and blood-rich areas before surgery. However, for patients wearing pacemakers and those with metal implants in their bodies, the radiofrequency current loop will generate heat through metal objects and damage normal tissues. The pacemaker may stop working under the interference of high-frequency current, causing the patient's death.

[0004] The radio frequency bipolar electrode can solve the above problems. The main working pole and the auxiliary working pole of the radio frequency bipolar electrode are at the two ends of the total working end, and the radio frequency current flows between the two poles. There is no need to stick a neutral electrode sheet, which saves the tedious operation process. For patients with metal implants in their bodies, this design avoids the heat generated by the radio frequency current loop through the metal object and reduces damage to normal tissues. If the patient wears a pacemaker, the radio frequency bipolar electrode can also prevent the high-frequency current from interfering with the normal operation of the pacemaker, reducing the risk of causing adverse reactions.

[0005] However, conventional radiofrequency bipolar electrodes only have a simple cold circulation structure, and both the main working electrode and the auxiliary working electrode have no micro-permeability structure. During the ablation process, tissue carbonization is severe and the ablation range is limited.

[0006] Therefore, in view of the above problems, it is urgent to provide a new radiofrequency ablation electrode to solve the above problems existing in the prior art. Summary of the invention

[0007] The object of the present invention is to provide a radiofrequency ablation electrode to solve the problems existing in the above-mentioned prior art. Both the main working electrode and the auxiliary working electrode have a micro-permeation structure. During the ablation process, it can avoid the problems of severe tissue carbonization and limited ablation range. Moreover, the axial distance between the main working electrode and the auxiliary working electrode can be adjusted, so that the total working end length can be changed, realizing the change of the ablation range, and it is suitable for the ablation of multiple lesions of different sizes. The total working end length includes the length of the main working electrode plus the distance between the main working electrode and the auxiliary working electrode plus the length of the auxiliary working electrode. During the change of the total working end length, the lengths of the main working electrode and the auxiliary working electrode can be kept unchanged, thereby maintaining the balance of the energy density on the main working electrode and the auxiliary working electrode, maintaining the balance of the ablation range, and avoiding the phenomenon of less ablation range in the front and more in the back, or more in the front and less in the back.

[0008] To achieve the above object, the present invention provides the following solutions:

[0009] The present invention provides a radiofrequency ablation electrode, comprising:

[0010] A working end, the working end includes a main working electrode and an auxiliary working electrode arranged coaxially, and the main working electrode and the auxiliary working electrode are separated by an insulating device arranged coaxially. The insulating device of the present invention is a polymer plastic tube, and the axial distance between the main working electrode and the auxiliary working electrode can be adjusted;

[0011] A radiofrequency generating source, the two poles of which are respectively connected to the main working electrode and the auxiliary working electrode through radiofrequency wires;

[0012] A cooling system, which can respectively introduce a circulating refrigerant medium into the inner channels of the main working electrode and the auxiliary working electrode. The refrigerant medium can be physiological saline to realize the cooling of the main working electrode, the polymer plastic tube, the auxiliary working electrode and the adjacent tissues; it can prevent the working end from adhering to the tissue, expand the ablation range, and reduce the degree of lesion carbonization.

[0013] A micro-permeation structure, including permeation openings respectively opened on the side walls of the main working electrode and the auxiliary working electrode. The permeation opening on the main working electrode is communicated with the inner channel, and the permeation opening on the auxiliary working electrode is communicated with the permeation channel of the auxiliary working electrode. A part of the refrigerant medium flowing back from the cooling system can enter the permeation channel. The permeation opening and the permeation channel of the auxiliary working electrode will move in real time as the auxiliary working electrode moves back and forth, and the permeation opening always remains evenly on the auxiliary working electrode; the physiological saline oozing out in a small amount from the micro-permeation structure can moisten the tissues around the working end, further avoiding tissue adhesion, facilitating mobile ablation operations such as for the thyroid gland, avoiding tissue carbonization, and being beneficial to postoperative recovery; at the same time, the physiological saline oozing out in a small amount can enhance the electrical conductivity of the tissue, reduce the working impedance, facilitate the continuous injection of radiofrequency energy, further expand the ablation range, facilitate the ablation of larger lesions such as benign prostatic hyperplasia and myocardial hypertrophy, improve the ablation efficiency, and can achieve complete ablation at one time.

[0014] Optionally, the main working electrode is fixed, and the secondary working electrode can move axially; the penetration port and penetration channel of the secondary working electrode will move in real time as the secondary working electrode moves axially, and the penetration port of the secondary working electrode is always evenly maintained on the secondary working electrode.

[0015] Optionally, the main working electrode and the secondary working electrode can simultaneously perform radiofrequency ablation and steam ablation. A small amount of exuded physiological saline is converted into water vapor under the action of radiofrequency current. The water vapor can be used as an auxiliary ablation medium, which can simultaneously achieve radiofrequency ablation and steam ablation of the main working electrode, radiofrequency ablation and steam ablation of the secondary working electrode, expand the ablation range, and strengthen the ablation effect.

[0016] Optionally, it further includes an inner needle tube, a first outer needle tube, and a second outer needle tube; one end of the first outer needle tube is fixedly provided with a needle tip, and the end face diameter of the connection end of the needle tip and the first outer needle tube is greater than the outer diameter of the first outer needle tube. The main working electrode is sleeved on the first outer needle tube, and one end thereof abuts against the end face of the needle tip, and the other end is hermetically connected to a first connection part sleeved on the first outer needle tube; the insulating device and the second outer needle tube are sequentially sleeved on the first connection part; the secondary working electrode is fixedly sleeved at the port of the second outer needle tube close to the insulating device. The length of the insulating device, that is, the polymer plastic tube, is at least 0.6 - 1.0 mm, fixed on the first insulating tube, and the front port is close to the rear end of the main working electrode. The outer diameter of the polymer plastic tube is greater than the inner diameter of the second outer needle tube and the inner diameter is less than the outer diameter of the second outer needle tube, which can block the front end face of the second outer needle tube and can prevent the two electrodes from contacting and causing a short circuit during the relative forward and backward sliding of the secondary working electrode with respect to the main working electrode; the tail end of the second outer needle tube slidably passes through a sealed cavity tube, and the sealed cavity tube can be communicated with the cooling system; the inner channel is formed between the inner needle tube and the first outer needle tube, and the penetration channel of the secondary working electrode is formed between the inner wall of the second outer needle tube and the first connection part; the radiofrequency wires of the radiofrequency generator are respectively connected to the first outer needle tube and the second outer needle tube.

[0017] Optionally, a second connection part sleeved on the second outer needle tube is hermetically provided at one end of the secondary working electrode away from the insulating device; an adjusting block is fixedly sleeved and connected at the tail end face of the second connection part, and the adjusting block can drive the second connection part, the second outer needle tube, and the secondary working electrode to move axially synchronously, and during the movement, the tail end of the second outer needle tube is always inside the sealed cavity tube.

[0018] Optionally, the first connection part is a first insulating tube provided on the first outer needle tube, and the second connection part is a second insulating tube provided on the second outer needle tube.

[0019] Optionally, the sealed cavity tube includes a circular sleeve with a sealed end, and a flexible plastic seal block is hermetically connected to the front end of the circular sleeve; the second outer needle tube hermetically slides through the flexible plastic seal block and extends into the circular sleeve; when the second outer needle tube slides, the tail port of the second outer needle tube does not extend beyond the flexible plastic seal block, and the second insulating tube on the second outer needle tube never enters the flexible plastic seal block.

[0020] Optionally, the penetration ports of the main working electrode include multiple circles of square holes opened along the axial direction of the main working electrode, and multiple circles of micro-holes arranged axially are opened on the side wall of the first outer needle tube sleeved with the main working electrode, and the micro-holes and the square holes are arranged staggeredly. After the refrigerant medium flows out from the micro-holes, it can enter the gap between the first outer needle tube and the main working electrode and flow out from the square holes, realizing the micro-penetration of the tissues around the main working electrode; the penetration ports of the auxiliary working electrode include multiple circles of liquid injection holes opened along the axial direction of the auxiliary working electrode, and one end of the liquid injection holes penetrates through the side wall of the second outer needle tube and is communicated with the inside of the second outer needle tube; in another preferred solution, the end of the second outer needle tube is fixedly and hermetically connected to one end of the auxiliary working electrode, so that the inside of the second outer needle tube is communicated with the inside of the auxiliary working electrode, and the liquid injection holes penetrate through the side wall of the auxiliary working electrode, and the function of communicating the liquid injection holes with the penetration channels of the auxiliary working electrode can be realized.

[0021] Optionally, the cooling system includes a return water cavity, a water inlet cavity, a water inlet pipe and a return water pipe. The inner cavity of the inner needle tube forms the water inlet pipe, and the inner channel between the outer wall of the inner needle tube and the inner wall of the first outer needle tube forms the return water pipe. The front end of the water inlet pipe is communicated with the front end of the return water pipe; there is a separating device between the water inlet cavity and the return water cavity. After the rear end of the inner needle tube passes through the return water cavity and penetrates through the separating device, it is communicated with the water inlet cavity; the rear end of the first outer needle tube is arranged in the return water cavity; the return water cavity can be communicated with the sealed cavity tube through a return pipe; the return water cavity and the water inlet cavity are respectively connected with a liquid supply device.

[0022] Optionally, the liquid supply device includes a refrigerant medium source and a refrigerant medium recovery device. The refrigerant medium source can provide the refrigerant medium, and the refrigerant medium flows into the water inlet cavity through the water inlet pipe. The refrigerant medium recovery device can recover the refrigerant medium, and the refrigerant medium flows from the return water cavity into the refrigerant medium recovery device through the return water pipe.

[0023] Optionally, the liquid injection hole gradually expands from the proximal end to the distal end. The size range of the liquid injection hole diameter at the proximal end is 0.1-0.4 mm, and the size range of the liquid injection hole diameter at the distal end is 0.5-1 mm. This ensures that the micro-permeation structure over the entire length range of the secondary working electrode can uniformly permeate the liquid. Moreover, since the liquid flowing towards the liquid injection hole on the secondary working electrode and the front port of the second outer needle tube has been depressurized in advance through the water return cavity and the gap space between the inner wall of the second outer needle tube and the outer wall of the first insulating tube, the liquid will not spray out from the liquid injection hole on the secondary working electrode and the front port of the second outer needle tube, but will slowly seep out, eliminating the need for a sleeve for pressure relief.

[0024] Optionally, the side wall of the sealing cavity tube is fixedly connected with a multi-channel valve, which is an N-channel valve, including one output port and N-1 input ports. It can control the valve to achieve the switching of independent communication between different input ports and the output port. Each time, only one input port can be connected to the output port, and the other input ports are not connected to the input-output port. The output port of the multi-channel valve communicates with the inside of the sealing cavity tube. One of the input ports of the multi-channel valve communicates with the return pipe, and Luer female connectors are provided at the remaining input ports of the multi-channel valve. The multi-channel valve can be switched to make its output port independently communicate with any input port.

[0025] Taking two input ports as an example, the second input port of the multi-channel valve is always connected to the tail end of the return pipe. When the valve of the multi-channel valve is switched to the second input port, the second input port communicates with the output port, and the first input port is not connected to the second input port and the output port. A small part of the return water at the tail end of the return pipe will flow through the second input port to the output port, then through the output port to the micro-permeation channel of the secondary working electrode, and flow out from the liquid injection hole, realizing the micro-permeation of the tissue around the secondary working electrode.

[0026] The first input port is a standard Luer female connector port, which is in a suspended state when not in use. When the valve of the multi-channel valve is switched to the first input port, the first input port communicates with the output port, and the second input port is not connected to the first input port and the output port. At this time, the Luer male connector of the output port of the syringe can be connected to the Luer female connector of the first input port of the multi-channel valve to realize the injection of external drugs into the tissue through the micro-permeation structure of the secondary working electrode. At the same time, the liquid of the diseased tissue can also be aspirated through the micro-permeation channel on the secondary working electrode.

[0027] Optionally, the lengths of the main working electrode and the secondary working electrode are different, and the maximum adjustable range of the axial distance between the main working electrode and the secondary working electrode is the length dimension of the shorter one of the main working electrode and the secondary working electrode.

[0028] Optionally, the length of the main working electrode is the same as that of the auxiliary working electrode, and the maximum adjustable range of the axial distance between the main working electrode and the auxiliary working electrode is the length dimension of the main working electrode or the length dimension of the auxiliary working electrode.

[0029] Optionally, the RF wire includes a first RF wire and a second RF wire. The front end of the first RF wire is connected to the main working electrode, and the front end of the second RF wire is connected to the auxiliary working electrode. The tail end of the first RF wire is connected with a first RF plug, and the tail end of the second RF wire is connected with a second RF plug. The first RF plug and the second RF plug are respectively connected to two poles of an RF generating source, so as to realize the conduction of RF current between the main working electrode and the auxiliary working electrode, ablate tissues. The RF current conducts between the two poles and does not flow to tissues outside the lesion. During ablation, it is not necessary to paste a neutral electrode patch.

[0030] Optionally, a conduction switch is provided between the first RF wire and the second RF wire, which can realize the conversion from bipolar to monopolar. When the conduction switch is turned on, the first RF wire and the second RF wire are electrically connected. At this time, the main working electrode and the auxiliary working electrode are converted into a monopolar electrode, that is, the RF ablation electrode is a monopolar electrode. A neutral electrode patch needs to be pasted during ablation, and the ablation range is larger. When the conduction switch is turned off, the first RF wire and the second RF wire are not connected. At this time, the main working electrode and the auxiliary working electrode are converted into a bipolar electrode, that is, the RF ablation electrode is a bipolar electrode. A neutral electrode patch does not need to be pasted during ablation, and the ablation range is large and precisely controllable.

[0031] The present invention has achieved the following technical effects compared with the prior art:

[0032] The working end of the present invention has a bipolar composite structure of a main working electrode and a secondary working electrode. A self-loop of radio frequency current is formed between the main working electrode and the secondary working electrode. During ablation, it is not necessary to attach a neutral electrode patch, which not only maintains the unique advantages of precise control of radio frequency ablation but is also particularly suitable for patients with metal in the body or a cardiac pacemaker who have relatively high requirements for ablation accuracy and a relatively large ablation range; the cooling system can prevent the working end from adhering to tissues, expand the ablation range, and reduce the degree of carbonization of the lesion; the micro-permeable structures on the outside of the main working electrode and the micro-permeable structure on the outside of the secondary working electrode enable the slightly exuded physiological saline to infiltrate the tissues around the working end, further avoiding tissue adhesion, facilitating mobile ablation for the thyroid gland, avoiding tissue carbonization, and being conducive to postoperative recovery; the penetration channels and penetration ports of the secondary working electrode of the present invention can introduce some refrigerant media in the return water cavity through the return pipe, realizing a self-loop of the refrigerant media at the penetration channels and penetration ports of the secondary working electrode. Without external structures such as pumps or syringes, by using the refrigerant media returned by the cooling system, a small amount of liquid perfusion can be achieved at the penetration channels and penetration ports of the secondary working electrode; at the same time, the slightly exuded physiological saline can enhance the electrical conductivity of the tissue, reduce the working impedance, facilitate the continuous injection of radio frequency energy, further expand the ablation range, facilitate the ablation of larger lesions of prostate hyperplasia and larger lesions of myocardial hypertrophy, improve the ablation efficiency, and can achieve complete ablation in one go; during the ablation process, both the main working electrode and the secondary working electrode can generate radio frequency ablation and water vapor ablation, and the radio frequency resistive heat and the heat conduction of water vapor act on the tissue simultaneously, improving the ablation efficiency and expanding the ablation range. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0034] Figure 1 It is a schematic diagram of the overall structure of the radio frequency ablation electrode in the embodiment of the present invention;

[0035] Figure 2 It is a schematic diagram of the assembly process of the main working electrode in the embodiment of the present invention;

[0036] Figure 3 It is a schematic diagram of the assembly of the inner needle tube in the embodiment of the present invention;

[0037] Figure 4 It is a schematic diagram of the assembly of the polymer plastic tube and the first insulating tube in the embodiment of the present invention;

[0038] Figure 5 It is a schematic diagram of the assembly process of the secondary working electrode in the embodiment of the present invention;

[0039] Figure 6 Schematic diagram of the micro-permeation structure of the secondary working electrode in the embodiment of the present invention;

[0040] Figure 7 Schematic diagram of the minimum adjustment range between the primary working electrode and the secondary working electrode in the embodiment of the present invention;

[0041] Figure 8 Schematic diagram of the real-time adjustment range between the primary working electrode and the secondary working electrode in the embodiment of the present invention;

[0042] Figure 9 Schematic diagram of realizing the micro-permeation function of the secondary working electrode through the second input port in the embodiment of the present invention;

[0043] Figure 10 Schematic diagram of realizing the injection function of the secondary working electrode through the first output port in the embodiment of the present invention;

[0044] Figure 11 Schematic diagram of realizing the liquid suction function of the secondary working electrode through the first output port in the embodiment of the present invention;

[0045] Figure 12 Schematic diagram of the wiring of the conduction switch in the embodiment of the present invention.

[0046] Description of reference numerals: 1. Needle tip; 2. Primary working electrode; 201. Sleeve; 202. Square hole; 3. High molecular plastic tube; 4. Secondary working electrode; 401. Liquid injection hole; 402. Exposed tube; 5. Second insulating tube; 6. Second outer needle tube; 7. Gap cavity; 8. First insulating tube; 9. First outer needle tube; 901. Micropore; 10. Inner needle tube; 11. Adjusting block; 12. Handle; 13. Flexible plastic sealing block; 14. Round sleeve; 15. Multi-channel valve; 151. First input port; 152. Control valve; 153. Second input port; 154. Output port; 16. Return pipe; 17. Return water cavity; 18. Water inlet cavity; 19. First RF wire; 20. First solder joint; 21. Second RF wire; 22. Second solder joint; 23. RF wire; 24. Conduction switch; 25. First RF plug; 26. Second RF plug; 27. Water inlet pipe; 28. Water return pipe; 29. Syringe. Detailed implementation manners

[0047] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0048] The object of the present invention is to provide a radiofrequency ablation electrode to solve the problems existing in the above-mentioned prior art. Both the main working electrode and the auxiliary working electrode have a micro-permeation structure. During the ablation process, it can avoid the problems of serious tissue carbonization and limited ablation range. Moreover, the axial distance between the main working electrode and the auxiliary working electrode can be adjusted, so that the total working end length can be changed, realizing the change of the ablation range, and it is suitable for the ablation of multiple lesions with different sizes. The total working end length includes the length of the main working electrode plus the distance between the main working electrode and the auxiliary working electrode plus the length of the auxiliary working electrode. During the change of the total working end length, the lengths of the main working electrode and the auxiliary working electrode can be kept unchanged, thereby maintaining the balance of the energy density on the main working electrode and the auxiliary working electrode, and maintaining the balance of the ablation range, without the phenomenon of less ablation range in the front and more in the back, or more in the front and less in the back.

[0049] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0050] The radiofrequency bipolar electrode known to the present inventor only has a simple cold circulation structure. The main working electrode has no micro-permeation structure, and the auxiliary working electrode has no micro-permeation structure. During the ablation process, the tissue carbonization is serious and the ablation range is limited; there is no liquid injection channel and it is impossible to combine drugs for treatment. For large prostate hyperplasia or large myocardial hypertrophy lesions, they cannot be completely ablated in a single time, and the ablation efficiency is low. In clinical ablation treatment for prostate hyperplasia, steam ablation is often used. Steam ablation uses a steam generator to generate high-temperature water vapor, and then injects the water vapor into the lesion tissue to cause thermal damage through heat conduction. To avoid damaging the normal physiological functions of the prostate, steam ablation often requires repeated multi-point and multiple ablations to complete the treatment, and the ablation efficiency is also low.

[0051] For the treatment of large lesions, cold circulation single-needle electrodes or perfusion single-needle electrodes are often used. For example, an adjustable water injection ablation electrode needle known to the present inventor only has a perfusion structure and no cold circulation structure. The refrigerant medium (normal saline) flows out of the liquid storage tank and directly injects into the lesion tissue through multiple micropores provided on the outer needle tube, and there is no refrigerant medium flowing back to the liquid storage tank. The normal saline penetrates into the tissue, changing the impedance of the lesion tissue, making the radiofrequency ablation range larger. At the same time, this structure has the following disadvantages: without a cold circulation structure, the refrigerant medium only perfuses and does not flow back, and cannot timely take away the heat of the working end and the surrounding tissue, resulting in tissue adhesion to the working end, thus causing the micropores on the working end to be blocked. When the flow rate of the refrigerant medium remains unchanged, the blockage of the pores causes the liquid in the needle tube to flow out from other micropores, and the amount of liquid flowing out of the micropores increases, which may spread around in a jet-like manner, resulting in an irregular ablation shape and affecting the safety of ablation.

[0052] To solve the problems encountered in the above technologies, the present invention provides a radiofrequency ablation electrode, as Figures 1 to 5As shown, it includes a working end, a radio frequency generating source, a cooling system and a micro-permeation structure. The working end of this embodiment includes a main working electrode 2 and a secondary working electrode 4 arranged coaxially. A polymer plastic tube 3 arranged coaxially is used to separate the main working electrode 2 and the secondary working electrode 4, and the axial distance between the main working electrode 2 and the secondary working electrode 4 can be adjusted; the two poles of the radio frequency generating source are respectively connected to the main working electrode 2 and the secondary working electrode 4 through radio frequency wires; the cooling system can introduce a circulating refrigerant medium into the inner channels of the main working electrode 2 and the secondary working electrode 4 to achieve cooling of the main working electrode 2, the polymer plastic tube 3, the secondary working electrode 4 and adjacent tissues; it can prevent the working end from adhering to tissues, expand the ablation range, and reduce the degree of carbonization of the lesion.

[0053] In one embodiment, the micro-permeation structure includes permeation ports respectively opened on the side walls of the main working electrode 2 and the secondary working electrode 4. The permeation port on the main working electrode 2 is communicated with the inner channel, and the permeation port on the secondary working electrode 4 is communicated with the permeation channel of the secondary working electrode 4. The permeation port and the permeation channel of the secondary working electrode 4 will move in real time with the forward and backward movement of the secondary working electrode 4, and its permeation port always remains evenly on the secondary working electrode 4; the physiological saline slightly exuded by the micro-permeation structure can moisten the tissues around the working end, further avoid tissue adhesion, facilitate mobile ablation for the thyroid gland, avoid tissue carbonization, and is beneficial to postoperative recovery; at the same time, the slightly exuded physiological saline can enhance the electrical conductivity of the tissues, reduce the working impedance, facilitate the continuous injection of radio frequency energy, further expand the ablation range, facilitate the ablation of larger lesions of prostate hyperplasia and larger lesions of myocardial hypertrophy, improve the ablation efficiency, and can achieve complete ablation at one time.

[0054] In a preferred embodiment, in order to realize the functions of the working end, the cooling system and the micro-permeation structure, this embodiment designs structures such as the inner needle tube 10, the first outer needle tube 9, and the second outer needle tube 6. The first outer needle tube 9 is sleeved on the inner needle tube 10. The main working electrode 2 is located at one end of the first outer needle tube 9 close to the needle tip. The main working electrode 2 of this embodiment includes a sleeve 201. The sleeve 201 is installed at the first outer needle tube 9 close to the needle tip. A first solder joint 20 is provided at the side wall of the first outer needle tube 9 away from the needle tip. The first solder joint is connected to the radio frequency source through a radio frequency wire. The inner needle tube 10 is inserted into the first outer needle tube 9, and the front end of the inner needle tube 10 extends into the front end of the needle tip. A first insulating tube 8 is provided on the surface of the first outer needle tube 9 behind the main working electrode 2. The first insulating tube 8 of this embodiment is a heat-shrinkable tube with a thin-wall structure. A small section of polymer plastic tube 3 is sleeved on the front surface of the first insulating tube 8. The rear end of the first insulating tube 8 is close to the first solder joint 20. One end of the polymer plastic tube 3 is close to the tail end of the main working electrode 2. A second outer needle tube 6 is sleeved behind the polymer plastic tube 3. The second outer needle tube 6 is sleeved on the surface of the first insulating tube 8. The inner wall of the second outer needle tube 6 is closely attached to the first insulating tube 8. The front port of the second outer needle tube 6 is closely attached to the tail end of the polymer plastic tube 3. The auxiliary working electrode 4 is located at one end of the second outer needle tube 6 close to the tail end of the polymer plastic tube 3. A second insulating tube 5 is provided on the second outer needle tube 6 at the rear part of the auxiliary working electrode 4. The second insulating tube 5 of this embodiment also adopts a heat-shrinkable tube with a thin-wall structure; a second solder joint 22 is provided on the side wall of the second outer needle tube 6. The second solder joint 22 is connected to the radio frequency source through a corresponding radio frequency wire; the tail end of the second outer needle tube 6 slides through a sealing cavity tube, and the sealing cavity tube can be communicated with the cooling system; the gap cavity 7 between the inner needle tube 10 and the first outer needle tube 9 forms a common inner channel for the main working electrode 2 and the auxiliary working electrode 4, and the permeation channel of the auxiliary working electrode 4 is formed between the inner wall of the second outer needle tube 6 and the first insulating tube 8.

[0055] In this embodiment, it should also be noted that the needle tip 1 is welded to the front end of the first outer needle tube 9. The diameter of the tail end of the needle tip 1 is larger than the diameter of the first outer needle tube 9, and the diameter of the tail end of the needle tip 1 is the same as the outer diameter of the sleeve 201, which is convenient for puncture; both the first outer needle tube 9 and the second outer needle tube 6 are made of metal materials, which is convenient for conducting electricity. The polymer plastic tube 3 is made of silicone material. The silicone material is an insulator, which isolates the current and prevents short circuit; the front end of the inner needle tube 10 extends into the needle tip 1, so that the refrigerant medium can reach the needle tip 1 part and reduce the carbonization of the tissue at the needle tip 1 part.

[0056] Such as Figure 6 , Figure 7 and Figure 8As shown, in this embodiment, the secondary working electrode 4 further includes an adjustment structure. The adjustment block 11 of the adjustment structure is fixed on the second insulating tube 5, and the end face of the second insulating tube 5 is flush with the end face of the adjustment block 11. The sealed cavity tube of this embodiment includes a round sleeve 14 with one end closed and the other end hermetically connected to a flexible plastic seal block 13. The second outer needle tube 6 passes through the flexible plastic seal block 13 and extends into the round sleeve 14. The end of the round sleeve 14 is sealed. When the adjustment block 11 slides, it drives the second outer needle tube 6, the secondary working electrode 4, and the second insulating tube 5 on the second outer needle tube 6 to move back and forth. The end of the second outer needle tube 6 is always inside the round sleeve 14, realizing the back-and-forth movement of the secondary working electrode 4 on the second outer needle tube 6 and the liquid injection holes 401 on the secondary working electrode 4, and the distance between the secondary working electrode 4 and the main working electrode 2 changes. The micro-permeation structure on the secondary working electrode 4 can, during the forward and backward adjustment of the secondary working electrode 4, keep the liquid on the secondary working electrode 4 uniformly permeated as the secondary working electrode 4 moves back and forth, always maintaining uniformity on the secondary working electrode, expanding the ablation range, and making the ablation range more regular; the liquid outlet of the micro-permeation structure on the secondary working electrode 4 is the liquid injection hole 401, which is located on the exposed tube 402 of the secondary working electrode, improving the electrical conductivity of adjacent tissues, expanding the ablation range, and ensuring the uniformity and regularity of the ablation range.

[0057] In this embodiment, it should also be noted that the outer diameter of the high molecular plastic tube 3 is greater than the inner diameter of the second outer needle tube 6, and the inner diameter of the high molecular plastic tube 3 is less than the outer diameter of the second outer needle tube 6, which can block the front end face of the second outer needle tube 6 and prevent the two electrodes from contacting and causing a short circuit during the forward and backward sliding of the secondary working electrode 4 relative to the main working electrode 2; during the adjustment process, the adjustment range is limited. The minimum range is not less than the length of the high molecular plastic tube 3 to prevent the two electrodes from being too close and causing a short circuit, and the maximum range is the length of the shorter one of the main working electrode 2 and the secondary working electrode 4 to prevent the two electrodes from being too far apart and the ablation range from being irregular, such as Figure 7 and Figure 8As shown in the figure, X in the figure is the distance that the auxiliary working electrode 4 can move axially, L is the length of the polymer plastic pipe 3, the maximum length of L + X is the length of the shorter one of the main working electrode 2 and the auxiliary working electrode 4, and the minimum length of L + X is the length of the polymer plastic pipe 3. The distance between the main working electrode 2 and the auxiliary working electrode 4 is adjustable, which can change the total working end length and realize the change of the ablation range. The total working end length includes the length of the main working electrode 2, the distance between the main working electrode and the auxiliary working electrode 4, and the length of the auxiliary working electrode 4: The present invention can realize the change of the ablation range by changing the total working end length, and is suitable for the ablation of multiple lesions with different sizes. By changing the distance between the main working electrode 2 and the auxiliary working electrode 4, the change of the total working end length is realized, rather than changing the length of the main working electrode 2 or the length of the auxiliary working electrode. During the process of adjusting the total working end length, the present invention can keep the lengths of the main working electrode 2 and the auxiliary working electrode 4 unchanged, thereby maintaining the balance of the energy density on the main working electrode 2 and the auxiliary working electrode 4, maintaining the balance of the ablation range, and avoiding the phenomenon of less ablation range in the front and more in the back, or more in the front and less in the back. Therefore, the present invention can not only realize bipolar radiofrequency ablation, but also realize the adjustability of the ablation range, improve the ablation accuracy, and further realize the balance of the ablation range.

[0058] In this embodiment, as Figure 1 shown, the liquid supply device includes a refrigerant medium source and a refrigerant medium recovery device. The refrigerant medium source can provide the refrigerant medium, and the refrigerant medium flows into the water cavity 18 through the water inlet pipe 27. The refrigerant medium recovery device can recover the refrigerant medium, and the refrigerant medium flows into the refrigerant medium recovery device from the return water cavity 17 through the return water pipe 28; both the water inlet cavity 18 and the return water cavity 17 are located in the handle 12. The water inlet cavity 18 is located at the rear end of the first outer needle tube 9 and is connected to the water inlet pipe 27. The return water cavity 17 is located at the rear end of the inner needle tube 10 and is connected to the return water pipe 28; the water inlet cavity 18 and the return water cavity 17 are separated by a separation device. After the rear end of the inner needle tube 10 passes through the return water cavity 17 and penetrates the separation device, it is connected to the water inlet cavity 18. The inner needle tube 10 is hermetically arranged at the penetration position of the separation device to avoid leakage; the rear end of the first outer needle tube 9 is arranged in the return water cavity 17; the return water cavity 17 can be connected to the circular sleeve 14 through the return pipe 16; In this embodiment, as Figures 1 to 6As shown, the main working electrode 2 and the auxiliary working electrode 4 share a cooling system to achieve cooling of the main working electrode 2, the polymer plastic pipe 3, the auxiliary working electrode 4 and the adjacent tissues; the cooling system includes a water inlet pipe and a water return pipe. The water inlet pipe is composed of an inner needle tube 10, and the water return pipe is composed of an annular channel, namely a gap cavity 7, between the outer wall of the inner needle tube 10 and the inner wall of the first outer needle tube 9. The front end of the water inlet pipe is communicated with the front end of the water return pipe. The liquid inlet port of the micro-permeable structure of the main working electrode 2 is communicated with the front end of the water return pipe of the cooling system and is located at the front end of the first outer needle tube 9. The refrigerant medium source can provide the refrigerant medium. The refrigerant medium flows into the water inlet cavity 18 through the water inlet pipe 27, enters the inner needle tube 10 through the water inlet cavity 18, flows to the end of the inner needle tube 10, then enters the annular inner channel between the inner needle tube 10 and the first outer needle tube 9, and then flows back into the water return cavity 17. During this period, part of the refrigerant medium oozes out through the micro-permeable structure of the main working electrode 2 to the working position. The refrigerant medium recovery device can recover the refrigerant medium. The refrigerant medium flows from the water return cavity 17 through the water return pipe 28 into the refrigerant medium recovery device.

[0059] In this embodiment, a multi-channel valve 15 is fixedly connected to the side wall of the circular sleeve 14. The circular sleeve 14 is communicated with the output port 154 of the multi-channel valve 15. One of the input ports of the multi-channel valve 15 is communicated with the return pipe 16, and the other end of the return pipe 16 is communicated with the water return pipe 28. Thus, part of the refrigerant medium flowing back from the water return cavity 17 enters the circular sleeve 14 through the return pipe 16, flows through the inside of the second outer needle tube 6 to the position where the auxiliary working electrode 4 is located, and then flows out to the working position through the end outlet of the second outer needle tube 6 and the liquid injection hole 401 of the auxiliary working electrode 4. Only one input port can be communicated with the output port 154 at a time, ensuring the independent communication of the output port 154, enabling the switching of the input channels, and realizing the switching of different functions of the liquid seepage port of the micro-permeable structure of the auxiliary working electrode 4.

[0060] As Figure 9As shown in the figure, taking the multi-channel valve 15 with two input ports as an example, in this embodiment, the second input port 153 of the multi-channel valve 15 is communicated with the end of the return pipe 16. For example, before ablation, the valve of the multi-channel valve 15 can be switched to the first input port 151, and an anesthetic drug is injected through an external syringe 29. The anesthetic drug enters the circular sleeve 14 through the output port 154 of the multi-channel valve 15 and finally oozes out from the micro-permeable structure of the auxiliary working electrode 4, so that the anesthetic drug can be directly injected into the lesion to achieve the injection of the anesthetic drug. During ablation, by adjusting the position of the control valve 152 of the multi-channel valve 15, its valve can be switched to the second input port 153. The second input port 153 is always communicated with the return pipe 16 of the cooling system, and the coolant will enter the output port 154 through the second input port 153 of the multi-channel valve 15. The coolant enters the micro-permeable structure of the auxiliary working electrode through the output port 154 of the multi-channel valve 15 and oozes out from the micro-permeable structure, realizing the cooling of the auxiliary working electrode 4 and the tissue adjacent to the auxiliary working electrode 4, avoiding tissue carbonization and adhesion, and also reducing tissue impedance to achieve a larger ablation range. After ablation is completed, the valve of the multi-channel valve 15 can also be switched to the first input port 151, and a combined therapeutic drug is injected through an external syringe. The micro-permeable structure of the present invention has a narrow space, which can avoid more drugs remaining in the permeation space. Usually, drugs are relatively expensive, thus avoiding waste of drugs.

[0061] Specifically, when the valve of the multi-channel valve 15 is switched to the second input port 153, a small part of the return water at the end of the return water pipe 28 enters the return pipe 16, then flows to the output port 154 through the second input port 153, flows into the circular sleeve 14 through the output port 154, and reaches the micro-permeable structure of the auxiliary working electrode 4 through the gap between the second outer needle tube 6 and the first insulating tube 8. During ablation, the cooling and micro-permeation functions of the two working electrodes can be realized without external liquid injection, simplifying the surgical operation process. The permeation ports of the micro-permeable structure of the auxiliary working electrode 4 include multiple circles of liquid injection holes 401 axially opened along the exposed tube 402 of the auxiliary working electrode 4. One end of the liquid injection hole 401 penetrates the side wall of the second outer needle tube 6 and is communicated with the inside of the second outer needle tube 6; in another preferred solution, the end of the second outer needle tube 6 is fixedly and sealedly connected to one end of the exposed tube 402 of the auxiliary working electrode 4, so that the inside of the second outer needle tube 6 is communicated with the inside of the auxiliary working electrode 4, and the liquid injection hole 401 penetrates the side wall of the auxiliary working electrode 4, realizing the function of communicating the liquid injection hole 401 with the permeation channel of the auxiliary working electrode 4; realizing micro-permeation of the tissue around the auxiliary working electrode 4, maintaining a low-impedance environment throughout the process, smooth energy injection, and slight tissue carbonization.

[0062] The cold medium that seeps out of the main working electrode 2 and the auxiliary working electrode 4 further cools the total working end and its surrounding tissues. The cold medium is usually sterile saline, which can conduct radio frequency current during the seepage process, enhance the conductivity of the tissue, reduce the impedance between the main working electrode and the auxiliary working electrode before ablation, maintain a low-impedance working environment between the main working electrode and the auxiliary working electrode during ablation, and continuously output high power throughout the entire ablation process, solving the problem of energy injection, improving ablation efficiency, and expanding the ablation range; trace amounts of saline that seeps out are converted into water vapor under the action of radio frequency current, and water vapor can be used as an auxiliary ablation medium, which can simultaneously realize radio frequency ablation and steam ablation of the main working electrode, and radio frequency ablation and steam ablation of the auxiliary working electrode, thereby expanding the ablation range and enhancing the ablation effect.

[0063] The main working electrode 2 and the auxiliary working electrode 4 of this embodiment use the same cooling system, which can realize cooling of the main working electrode 2, the auxiliary working electrode 4 and the adjacent tissues. The main working electrode 2 and the auxiliary working electrode 4 have micro-permeable structures. During the ablation process, the cold medium can be automatically injected into the lesion tissue through the micro-permeable structure on the main working electrode 2 and the micro-permeable structure on the auxiliary working electrode 4, respectively, to cool the total working end and the adjacent tissues, avoid high temperature causing carbonization and adhesion of tissues, and expand the ablation range. At the same time, the cold medium injected into the lesion can enhance the conductivity of the tissue and further expand the ablation range. The problem of the small ablation range of conventional bipolar radiofrequency ablation electrodes is solved, and the unique safety and controllability of radiofrequency ablation is maintained. It can be used on patients with metal or pacemakers installed in their bodies, especially for lesion tissues that require a large ablation range and high ablation accuracy, such as myocardial hypertrophy, prostatic hyperplasia and other lesion tissues with relatively high requirements.

[0064] like Figure 10 , Figure 11 As shown, in this embodiment, a Luer connector is used to achieve connection between ports. When the valve of the multi-channel valve 15 is switched to the first input port 151, the first input port 151 is connected to the output port 154. The Luer male connector of the output port of the syringe can be connected to the Luer female connector of the first input port 151 of the multi-channel valve 15 to achieve injection of external drugs into surrounding tissues through the micro-permeation structure of the auxiliary working electrode 4. At the same time, the micro-permeation structure on the auxiliary working electrode 4 can also be used to achieve suction of the liquid in the lesion tissue.

[0065] In this embodiment, if Figure 2As shown in the figure, the micro-permeation structure of the main working electrode 2 includes multiple circles of micropores 901 axially arranged on the first outer needle tube 9. Multiple circles of square holes 202 are axially arranged on the sleeve 201 of the main working electrode 2. The micropores 901 and the square holes 202 are staggeredly arranged from front to back along the axial direction of the first outer needle tube 9. That is, along the axial direction, the position of the micropores 901 on the first outer needle tube 9 corresponds to the tube wall of the sleeve 201 (the position where the square holes 202 are not provided). The tube wall of the sleeve 201 can block the micropores 901 to prevent the refrigerant medium from spraying out. There is a small gap between the sleeve 201 and the first outer needle tube 9. After the refrigerant medium flows out of the micropores 901, it can enter the gap between the first outer needle tube 9 and the sleeve 201 and seep out from the square holes 202. This design not only ensures the cold cycle function of the electrode but also ensures that the micropores 901, the small gap between the first outer needle tube 9 and the sleeve 201 are not blocked during the ablation process, causing tissue carbonization and adhesion, and ensuring that the refrigerant medium can continuously and evenly seep out from each hole.

[0066] As Figure 12 shown, the radiofrequency wire 23 includes a first radiofrequency wire 19 and a second radiofrequency wire 21. The front end of the first radiofrequency wire 19 is connected to the main working electrode 2 through a first solder joint 20. The front end of the second radiofrequency wire 21 is connected to the auxiliary working electrode 4 through a second solder joint 22. The tail end of the first radiofrequency wire 19 is connected with a first radiofrequency plug 25, and the tail end of the second radiofrequency wire 21 is connected with a second radiofrequency plug 26. The first radiofrequency plug 25 and the second radiofrequency plug 26 are respectively connected to two poles of a radiofrequency generating source. It realizes the conduction of radiofrequency current between the main working electrode 2 and the auxiliary working electrode 4 to ablate tissue. The radiofrequency current conducts between the two poles and does not flow to tissues outside the lesion. During ablation, it is not necessary to paste a neutral electrode patch. A conduction switch 24 is provided between the first radiofrequency wire 19 and the second radiofrequency wire 21, which can realize the conversion from bipolar to monopolar. The conduction switch 24 in this embodiment is a boat-shaped switch. In this embodiment, the conduction switch 24 can connect the first radiofrequency wire 19 and the second radiofrequency wire 21. When the conduction switch 24 is pressed, the main working electrode 2 and the auxiliary working electrode 4 are electrically connected to realize the conversion from bipolar to monopolar. At this time, it is necessary to connect a neutral electrode patch, and the ablation range is larger. When the conduction switch 24 is disconnected, the first radiofrequency wire 19 and the second radiofrequency wire 21 are not connected. At this time, the conversion from monopolar to bipolar is realized, that is, the radiofrequency ablation electrode is a bipolar electrode. During ablation, it is not necessary to paste a neutral electrode patch, and the ablation range is large and precisely controllable.

[0067] In the present invention, specific examples are used to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. At the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A radiofrequency ablation electrode, characterized in that: include: A working end, wherein the working end comprises a coaxially arranged main working pole and an auxiliary working pole, the main working pole and the auxiliary working pole are separated by a coaxially arranged insulating device, and the axial distance between the main working pole and the auxiliary working pole is adjustable; A radio frequency generating source, the two electrodes of which are respectively connected to the main working electrode and the auxiliary working electrode through radio frequency wires; A cooling system capable of introducing circulating refrigerant into the inner channels of the main working electrode and the auxiliary working electrode; The micro-permeation structure comprises permeation ports respectively provided on the side wall of the main working electrode and the side wall of the auxiliary working electrode, the permeation port on the main working electrode is connected to the inner channel, the permeation port on the auxiliary working electrode is connected to the permeation channel of the auxiliary working electrode, and part of the refrigerant medium refluxed by the cooling system can enter the permeation channel; It also includes an inner needle tube, a first outer needle tube, and a second outer needle tube; a needle tip is fixedly provided at one end of the first outer needle tube, and the end surface diameter of the needle tip connected to the first outer needle tube is larger than the outer diameter of the first outer needle tube; the main working electrode is sleeved on the first outer needle tube, and one end thereof abuts against the end surface of the needle tip, and the other end is sealed and connected to a first connecting portion sleeved on the first outer needle tube; the first connecting portion is sleeved with the insulating device and the second outer needle tube in sequence; the second outer needle tube is fixedly sleeved with the auxiliary working electrode at the port close to the insulating device; the tail end of the second outer needle tube is slidably inserted into a sealed cavity tube, and the sealed cavity tube can be connected to the cooling system; a sealing cavity tube is formed between the inner needle tube and the first outer needle tube. The inner channel, the inner wall of the second outer needle tube and the first connecting part form a penetration channel for the auxiliary working electrode; the radio frequency wire of the radio frequency generating source is respectively connected to the first outer needle tube and the second outer needle tube; the end of the auxiliary working electrode away from the insulating device is sealed with a second connecting part sleeved on the second outer needle tube; the tail end surface of the second connecting part is fixedly sleeved with an adjusting block, and the adjusting block can drive the second connecting part, the second outer needle tube and the auxiliary working electrode to move axially synchronously, and during the movement, the tail end of the second outer needle tube is always in the sealed cavity; the sealed cavity includes a round sleeve with a tail end seal, and the front end of the round sleeve is sealed with a flexible plastic sealing block; the second outer needle tube slides through the seal A flexible plastic sealing block extends into the circular sleeve; the penetration port of the main working pole includes multiple circles of square holes opened along the axial direction of the main working pole, and the side wall of the first outer needle tube sleeved with the main working pole is provided with multiple circles of microholes arranged along the axial direction, and the microholes and the square holes are arranged alternately; the penetration port of the auxiliary working pole includes multiple circles of injection holes opened along the axial direction of the auxiliary working pole, and one end of the injection hole passes through the side wall of the second outer needle tube and is connected to the inside of the second outer needle tube; the cooling system includes a return water chamber, a water inlet chamber, a water inlet pipe and a return water pipe, the inner cavity of the inner needle tube forms the water inlet pipe, the inner channel between the outer wall of the inner needle tube and the inner wall of the first outer needle tube forms the return water pipe, and the front end of the water inlet pipe It is connected with the front end of the return water pipe; a partition device is provided between the water inlet chamber and the return water chamber, and the rear end of the inner needle tube passes through the return water chamber and the partition device and is connected with the water inlet chamber; the rear end of the first outer needle tube is inserted into the return water chamber; the return water chamber can be connected with the sealed cavity tube through a reflux pipe; the return water chamber and the water inlet chamber are respectively connected with a liquid supply device; a multi-channel valve is fixedly connected to the side wall of the sealed cavity tube, the output port of the multi-channel valve is connected with the inside of the sealed cavity tube, one of the input ports of the multi-channel valve is connected with the reflux pipe, and the remaining input ports of the multi-channel valve are provided with Luer female connectors, and the multi-channel valve can be switched to make its output port independently connected with any input port.

2. The radiofrequency ablation electrode according to claim 1, characterized in that: The main working electrode is fixed, and the auxiliary working electrode can move axially; the permeation port and permeation channel of the auxiliary working electrode will move in real time with the axial movement of the auxiliary working electrode, and the permeation port of the auxiliary working electrode is always evenly maintained on the auxiliary working electrode.

3. The radiofrequency ablation electrode according to claim 1, characterized in that: The main working electrode and the auxiliary working electrode can simultaneously realize radiofrequency ablation and steam ablation.

4. The radiofrequency ablation electrode according to claim 1, characterized in that: The first connecting portion is a first insulating tube disposed on the first outer needle tube, and the second connecting portion is a second insulating tube disposed on the second outer needle tube.

5. The radiofrequency ablation electrode according to claim 1, characterized in that: The liquid supply device includes a refrigerant source and a refrigerant recovery device. The refrigerant source can provide the refrigerant and allow the refrigerant to flow into the water chamber through a water inlet pipe. The refrigerant recovery device can recover the refrigerant and the refrigerant flows from the return water chamber through a return water pipe into the refrigerant recovery device.

6. The radiofrequency ablation electrode according to claim 1, characterized in that: The injection holes are expanded from the proximal end to the distal end, the injection holes at the proximal end have a diameter range of 0.1-0.4 mm, and the injection holes at the distal end have a diameter range of 0.5-1 mm.

7. The radiofrequency ablation electrode according to claim 1, characterized in that: The length of the main working pole is different from that of the auxiliary working pole, and the maximum range of the adjustable axial distance between the main working pole and the auxiliary working pole is the length of the shorter one of the main working pole and the auxiliary working pole.

8. The radiofrequency ablation electrode according to claim 1, characterized in that: The length of the main working pole is the same as that of the auxiliary working pole, and the maximum range of the adjustable axial distance between the main working pole and the auxiliary working pole is the length of the main working pole or the length of the auxiliary working pole.

9. The radiofrequency ablation electrode according to claim 1, characterized in that: The RF wire includes a first RF wire and a second RF wire, the front end of the first RF wire is connected to the main working pole, the front end of the second RF wire is connected to the auxiliary working pole, the tail end of the first RF wire is connected to the first RF plug, and the tail end of the second RF wire is connected to the second RF plug; the first RF plug and the second RF plug are respectively connected to the two poles of the RF source.

10. The radiofrequency ablation electrode according to claim 9, characterized in that: A conduction switch is provided between the first radio frequency wire and the second radio frequency wire. When the conduction switch is turned on, the first radio frequency wire and the second radio frequency wire are electrically connected. At this time, the main working electrode and the auxiliary working electrode are converted into monopolar electrodes. When the conduction switch is turned off, the first radio frequency wire and the second radio frequency wire are not connected, and at this time, the main working electrode and the auxiliary working electrode are converted into bipolar electrodes.

Images