Perfusion type radiofrequency ablation electrode

Abstract

The utility model relates to the technical field of medical instruments, in particular to a perfusion type radiofrequency ablation electrode which comprises a handle, an electrode tube fixed on the handle, a needle head fixed at the far end of the electrode tube and a radiofrequency connector electrically connected with the near end of the electrode tube, and a plurality of perfusion holes are formed in the outer wall, close to the needle head, of the electrode tube. A fluid cavity and a pair of liquid injection channels extending from the fluid cavity to the outer surface of the needle head are arranged in the needle head, and a liquid injection pipe is arranged in the electrode pipe in a penetrating mode. The end, extending into the handle, of the liquid injection pipe is connected with the inner wall of the electrode pipe in a sealed mode, a fluid channel communicated with the fluid cavity and an inner cavity of the liquid injection pipe is formed between the liquid injection pipe and the electrode pipe, and a water injection pipeline communicated with the liquid injection pipe is arranged outside the handle. According to the utility model, the outer side of the whole electrode working area can be ensured to have a low-impedance environment, the temperature of the needle head is controlled, and the adhesion phenomenon of the electrode in the operation process is effectively solved.

Description

Technical Field

[0001] This utility model relates to the field of medical device technology, and in particular to a perfusion-type radiofrequency ablation electrode. Background Technology

[0002] Radiofrequency ablation electrodes utilize the principle of radiofrequency ablation. Radiofrequency energy is transmitted to the treatment area via the ablation electrode. This energy oscillates at high frequency within the tissue, converting into heat, causing coagulative necrosis of the lesion. However, the treatment area is not always in a low-impedance, high-conductivity environment. For example, when treating lung tissue, which is mostly composed of alveoli with high operating impedance, increasing the output voltage is necessary to ensure treatment effectiveness. This can easily lead to localized tissue carbonization. To avoid this, saline solution is typically injected into the treatment area along the ablation electrode during ablation. The saline solution, under high temperature, forms high-temperature vapor, which diffuses to the vicinity of the lesion, reducing its impedance.

[0003] Because the micropores for water injection on the traditional ablation electrode are located on the electrode tube wall, it was found during the operation that the needle tip of the electrode could not make effective contact with the injected saline. At the same time, there was a lack of cooling measures when the area became hot, which caused the lesion tissue in this area to easily adhere during the operation, affecting the surgical outcome. Utility Model Content

[0004] To address the shortcomings of the existing technology, this invention provides an infusion-type radiofrequency ablation electrode.

[0005] The technical solution of this utility model is as follows: an infusion-type radiofrequency ablation electrode, comprising a handle, an electrode tube fixed on the handle, a needle fixed at the distal end of the electrode tube, and a radiofrequency connector electrically connected to the proximal end of the electrode tube. The electrode tube has multiple infusion holes on its outer wall near the needle. The needle has a fluid chamber and an injection channel extending from the fluid chamber to the outer surface of the needle. An injection tube is inserted through the electrode tube. One end of the injection tube extending into the handle is sealed to the inner wall of the electrode tube, and a fluid channel is formed between the injection tube and the electrode tube, communicating with the fluid chamber and the inner cavity of the injection tube. A water injection line communicating with the injection tube is provided outside the handle. By setting a fluid chamber and injection channel inside the needle, and injecting physiological saline into the fluid chamber and electrode tube through the injection tube, a portion of the physiological saline diffuses to the outside of the electrode tube through the irrigation hole on the electrode tube wall, and a portion of the physiological saline cools the needle and diffuses to the outside of the needle, so as to ensure that the entire outer side of the electrode working area has a low impedance environment and control the needle temperature, thereby effectively solving the problem of electrode adhesion during surgery.

[0006] The end of the injection tube away from the handle extends into the fluid chamber and is fixedly connected to the needle. A diversion hole connected to the fluid channel is provided on the injection tube.

[0007] The extension direction of the injection channel forms an angle of less than 90° with the axial direction of the needle tip toward the distal end.

[0008] The opening direction of the injection hole forms an angle of less than 90° with the axial direction of the electrode tube towards the distal end.

[0009] The extension direction of the injection channel forms an angle of 20°-70° with the axial direction of the needle tip toward the distal end.

[0010] The opening direction of the injection hole forms an angle of 20°-70° with the axial direction of the electrode tube towards the distal end.

[0011] Both the injection channel and the infusion orifice have distal ends with arc-shaped chamfered edges. The arc-shaped chamfered edges design can avoid the edge effect of conductors in the edge area during radiofrequency treatment caused by rough processing of the injection channel / infusion orifice opening, thereby preventing high-temperature carbonization.

[0012] The outer side of the electrode tube is coated with an insulating layer. One end of the insulating layer extends to the connection between the electrode tube and the handle, and the other end of the insulating layer and the electrode tube between the needle tip form the working section of the electrode tube.

[0013] A thermocouple is fixed inside the needle, and the thermocouple wire extends along the injection tube into the handle and is electrically connected to the radio frequency connector.

[0014] The beneficial effects of this invention are as follows: This solution sets up a fluid chamber and an injection channel inside the needle, and injects physiological saline into the fluid chamber and electrode tube through the injection tube. A portion of the physiological saline diffuses to the outside of the electrode tube through the irrigation hole on the electrode tube wall, and a portion diffuses to the outside of the needle, so as to ensure that the entire outer side of the electrode working area has a low impedance environment. At the same time, the physiological saline entering the fluid chamber also has a certain cooling effect to control the needle temperature, thereby effectively solving the problem of electrode adhesion during surgery. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model;

[0016] Figure 2 This is a cross-sectional schematic diagram of the present invention;

[0017] Figure 3 This is a cross-sectional view of the connection between the needle tip and the electrode tube in this utility model;

[0018] Figure 4 This is a perspective view of the connection between the needle tip and the electrode tube in this utility model.

[0019] Reference numerals: 1. Handle; 2. Electrode tube; 201. Injection port; 202. Fluid channel; 3. Needle; 301. Fluid chamber; 302. Injection channel; 4. Injection tube; 401. Diverter hole; 5. Water injection line; 6. Radio frequency connector; 7. Thermocouple; 8. Thermocouple wire; 9. Insulation layer; 10. Support plate; 11. Indicator light; 12. Ring magnet; 13. Magnetic coil. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solutions of this utility model, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Other embodiments obtained by those skilled in the art without creative effort should all fall within the protection scope of this utility model.

[0021] like Figures 1-3 As shown, this utility model provides an infusion-type radiofrequency ablation electrode, including a handle 1, an electrode tube 2 fixed on the handle 1, a needle 3 fixed at the distal end of the electrode tube 2, and a radiofrequency connector 6 electrically connected to the electrode tube 2. The electrode tube 2 has multiple infusion holes 201 on its outer wall near the needle 3. The needle 3 has a fluid chamber 301 inside and a liquid injection channel 302 extending from the fluid chamber 301 to the outer surface of the needle 3. A liquid injection tube 4 passes through the electrode tube 2. One end of the liquid injection tube 4 extending into the handle 1 is sealed to the inner wall of the electrode tube 2, and a fluid channel 202 is formed between the liquid injection tube 4 and the electrode tube 2, which communicates with the fluid chamber 301 and the inner cavity of the liquid injection tube 4. A water injection pipe 5 connected to the liquid injection tube 4 is provided outside the handle 1. The saline solution injected through the water injection line 5 enters the fluid channel 202 and the fluid chamber 301 through the injection line 4. The saline solution in the fluid channel 202 diffuses to the outside of the electrode tube 2 through the irrigation hole 201 on the wall of the electrode tube 2, and the saline solution in the fluid chamber 301 diffuses to the outside of the needle 3 through the injection line 302. This creates a low-impedance environment formed by the saline solution that surrounds the entire electrode working area, ensuring the uniformity of radiofrequency energy distribution. In addition, the saline solution entering the fluid chamber 301 also has a certain cooling effect to prevent the needle 3 from overheating, thereby effectively solving the problem of electrode adhesion during the operation.

[0022] More preferably, the infusion hole 201 and the injection channel 302 are microporous structures with a diameter of 0.05mm-0.2mm. In this embodiment, the needle tip includes a pointed head, a cylindrical part with the same outer diameter as the electrode tube 2, and an insertion part that mates with the inner cavity of the electrode tube 2. The fluid chamber 301 extends from the insertion part into the pointed head. The injection channel 302 is divided into two groups, which are respectively connected to the outer side of the cylindrical part and the needle head 3. Each injection channel group consists of 3-4 injection channels 302 arranged circumferentially. The infusion holes 201 are divided into 3-4 groups, which are equally spaced on the wall of the electrode tube 2 in a direction away from the needle head 3. Each infusion hole group consists of 3-4 infusion holes 201 arranged circumferentially. Figure 1 As shown, the outer side of the electrode tube 2 is coated with an insulating layer 9 to cover the part of the electrode tube 2 that does not need to release energy. Specifically, one end of the insulating layer 9 extends to the connection between the electrode tube 2 and the handle 1, and the other end of the insulating layer 9 extends to the outer side of the injection hole 201 group closest to the handle 1.

[0023] More preferably, the end of the injection tube 4 away from the handle 1 extends into the fluid chamber 301 and is fixedly connected to the needle 3. The injection tube 4 is provided with a diversion hole 401 that communicates with the fluid channel 202. In order to ensure that the saline can effectively enter the fluid channel 202 and diffuse through the infusion hole 201, the size of the diversion hole 401 is not less than twice that of the infusion hole 201.

[0024] To improve the firmness of the electrode tube 2 installed inside the handle 1, such as Figure 2 As shown, the distal end of the electrode tube 2 is inserted into the handle 1 and then fixedly connected to the support plate 10 formed on the inner wall of the handle 1.

[0025] Further preferred, such as Figure 3 As shown, the extension direction of the injection channel 302 forms an angle of less than 90° with the axial direction of the needle 3 towards the distal end, and the opening direction of the irrigation hole 201 forms an angle of less than 90° with the axial direction of the electrode tube 2 towards the distal end, so that the physiological saline diffuses outward along the fluid flow direction, thereby concentrating and distributing it more concentrated around the working area of ​​the electrode to optimize the uniformity of radio frequency energy; the above angle is preferably an angle of 20°-70°, and more preferably 30°.

[0026] like Figure 4 As shown, both the injection channel 302 and the irrigation hole 201 have distal ends with arc-shaped chamfered edges. By designing the edges as arc-shaped chamfers, the rough processing of the openings of the injection channel 302 / irrigation hole 201 can prevent the edge effect of the conductor in the edge area during radiofrequency treatment, which could induce high-temperature carbonization.

[0027] like Figure 3As shown, in order to monitor the temperature at the position of the needle 3, a thermocouple 7 is fixed inside the needle 3. Preferably, for ease of installation and processing, the thermocouple 7 is fixed inside the fluid chamber 301. The thermocouple wire 8 of the thermocouple 7 extends along the injection tube 4 into the handle 1 and is electrically connected to the radio frequency connector 6.

[0028] To facilitate effective identification of the working status of the ablation electrode, this ablation electrode also includes an indicator light 11 and a ring magnet 12. The indicator light 11 is disposed through the handle 1, and the ring magnet 12 is sleeved on the outside of the electrode tube 2 and attached to the support plate 10. A magnetic induction coil 13 electrically connected to the indicator light 11 is wound around the ring magnet 12. When radio frequency current is passed through the electrode tube 2, a magnetic field is generated around the electrode tube 2, which in turn changes the magnetic flux passing through the magnetic induction coil 13, generating an induced current. The indicator light 11 lights up, indicating that the ablation electrode is in working condition.

[0029] Taking lung surgery as an example, when using this ablation electrode for surgery, the radiofrequency connector 6 is connected to the main unit, and the electrode is inserted into the area to be treated. The electrode tube 2 and needle 3 on the outside of the insulating layer 9 emit radiofrequency energy. At the same time, medical staff inject physiological saline into the water injection line 5 through a syringe or peristaltic pump. The physiological saline reaches the fluid chamber 301 along the injection tube 4, which initially cools the needle 3. At the same time, the physiological saline diffuses to the outside of the electrode tube 2 and the needle 3 through the injection channel 302 and the irrigation hole 201, respectively, and forms high-temperature vapor under the high temperature of the radiofrequency energy. A uniform and stable low-impedance working environment is formed between the electrode and the lesion tissue, which ensures the ablation effect while avoiding adhesion during the operation.

[0030] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A perfusion-type radiofrequency ablation electrode, comprising a handle, an electrode tube fixed to the handle, a needle fixed to the distal end of the electrode tube, and a radiofrequency connector electrically connected to the proximal end of the electrode tube, wherein the electrode tube has a plurality of perfusion holes on its outer wall near the needle, characterized in that, The needle has a fluid chamber inside and a liquid injection channel extending from the fluid chamber to the outer surface of the needle. A liquid injection tube is inserted through the electrode tube. One end of the liquid injection tube extending into the handle is sealed to the inner wall of the electrode tube, and a fluid channel is formed between the liquid injection tube and the electrode tube, which is connected to the fluid chamber and the inner cavity of the liquid injection tube. A water injection line connected to the liquid injection tube is provided outside the handle.

2. The perfusion-type radiofrequency ablation electrode according to claim 1, characterized in that, The end of the injection tube away from the handle extends into the fluid chamber and is fixedly connected to the needle. A diversion hole connected to the fluid channel is provided on the injection tube.

3. The perfusion-type radiofrequency ablation electrode according to claim 1, characterized in that, The extension direction of the injection channel forms an angle of less than 90° with the axial direction of the needle tip toward the distal end.

4. The perfusion-type radiofrequency ablation electrode according to claim 1, characterized in that, The opening direction of the injection hole forms an angle of less than 90° with the axial direction of the electrode tube towards the distal end.

5. The perfusion-type radiofrequency ablation electrode according to claim 3, characterized in that, The extension direction of the injection channel forms an angle of 20°-70° with the axial direction of the needle tip toward the distal end.

6. The perfusion-type radiofrequency ablation electrode according to claim 4, characterized in that, The opening direction of the injection hole forms an angle of 20°-70° with the axial direction of the electrode tube towards the distal end.

7. A perfusion-type radiofrequency ablation electrode according to any one of claims 1-6, characterized in that, Both the injection channel and the injection hole have distal ends with arc-shaped chamfered edges.

8. A perfusion-type radiofrequency ablation electrode according to any one of claims 1-6, characterized in that, The outer side of the electrode tube is coated with an insulating layer. One end of the insulating layer extends to the connection between the electrode tube and the handle, and the other end of the insulating layer and the electrode tube between the needle tip form the working section of the electrode tube.

9. A perfusion-type radiofrequency ablation electrode according to any one of claims 1-6, characterized in that, A thermocouple is fixed inside the needle, and the thermocouple wire extends along the injection tube into the handle and is electrically connected to the radio frequency connector.

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