Bipolar water-cooling radiofrequency ablation needle

Abstract

The utility model relates to a bipolar water-cooling radiofrequency ablation needle, and belongs to the technical field of medical instruments. The bipolar water-cooling radiofrequency ablation needle mainly comprises a needle head arranged at the farthest end of the ablation needle; the inner needle tube is a long and thin tube which is through front and back, and the needle head is connected with the inner needle tube; the outer needle tube is arranged outside the inner needle tube in a sleeving manner, and an insulating separator is arranged between the outer needle tube and the needle head; a middle insulating sleeve is also arranged between the outer needle tube and the inner needle tube; the water inlet pipe is arranged in the inner needle tube and divides an inner cavity of the inner needle tube into a water inlet channel and a water return channel. The cold cutting water cools the needle head, so that the temperature of the working end of the radiofrequency ablation needle can be effectively reduced, and tissue carbonization and adhesion are avoided.

Description

Technical Field

[0001] The utility model relates to a bipolar water-cooled radiofrequency ablation needle, belonging to the technical field of medical devices. Background Art

[0002] Radiofrequency ablation is currently widely used in the treatment of tumors in the liver, lungs, thyroid and other parts. A single-pole or multi-pole radiofrequency electrode is placed into the tumor tissue, and high-frequency alternating current is emitted through the electrode, so that the conductive ions or polarized molecules in the tissue cells quickly change directions and oscillate and rub against each other to generate heat energy, causing the local temperature of the tissue to be above 60°C, and the tumor cells rapidly undergo protein denaturation and coagulative necrosis, so as to achieve the purpose of treating tumors.

[0003] The radiofrequency ablation needle is a key instrument in radiofrequency ablation. The existing radiofrequency ablation needles can be divided into single-pole radiofrequency needles and bipolar radiofrequency needles according to the energy transmission method. The single-pole radiofrequency needle needs to be used in cooperation with a negative electrode plate, and it is difficult to accurately control the ablation range, and it is easy to have incomplete ablation during the ablation process. Moreover, improper pasting of the negative electrode plate will burn the skin of the patient, making the patient suffer from the pain of the tumor while also suffering from the pain of burns. The energy transfer of the bipolar radiofrequency ablation needle is limited between the two poles of the needle tube, and the energy transfer range is more accurate. While damaging the target tissue, the damage to other tissues is smaller, so the safety is higher.

[0004] The radiofrequency ablation needle can be divided into a non-water-cooled circulation radiofrequency needle and a water-cooled circulation radiofrequency needle according to whether there is a cooling medium flowing in the needle tube. Among them, for the non-water-cooled circulation, because there is no effective cooling measure when acting on the tumor tissue, it is easy to adhere to the tumor tissue and scald the skin during the treatment, resulting in treatment failure. When the water-cooled circulation acts on the tumor tissue, because the electrode needle has a hollow water-cooled circulation treatment inside, it can effectively maintain the temperature inside the electrode needle, so that the electrode needle is not easy to adhere to the tissue and will not scald the skin.

[0005] At present, the single-pole water-cooled circulation radiofrequency ablation needle is relatively common in clinical practice. Although the clinical use of the bipolar water-cooled circulation radiofrequency ablation needle has a good expected effect, it is extremely rare in clinical practice. This is because the internal space of the bipolar radiofrequency ablation needle is small, but the structure is complex, and there are certain difficulties in design and manufacturing.

[0006] The applicant further retrieved and found that the Chinese patent document with the authorization announcement number CN217853279U (application number 202221412262.5) discloses a bipolar water-cooled ablation electrode structure and an ablation device. In this patent, an isolation rod is welded or bonded to divide the water delivery cavity into a water inlet cavity and a water outlet cavity. Since the gap of the water delivery cavity between the inner sleeve and the outer sleeve is small, it is difficult to ensure the complete isolation of the water inlet cavity and the water outlet cavity due to the high difficulty in the process implementation of welding or bonding the isolation rod, which affects the water-cooled circulation effect. Summary of the Invention

[0007] The utility model provides a bipolar water-cooled radiofrequency ablation needle, which can cool the needle tip through water-cooling circulation to avoid adhesion of the needle tip to tissues.

[0008] To achieve the above purpose, the specific technical solution of the utility model is as follows: A bipolar water-cooled radiofrequency ablation needle mainly includes:

[0009] A needle tip, disposed at the farthest end of the ablation needle;

[0010] The inner needle tube is a slender tube that runs through the front and back, and the needle head is connected to the inner needle tube;

[0011] An outer needle tube is sleeved outside the inner needle tube, and an insulating spacer is provided between the outer needle tube and the needle;

[0012] An intermediate insulating sleeve is also provided between the outer needle tube and the inner needle tube;

[0013] The water inlet pipe is arranged inside the inner needle tube, and divides the inner cavity of the inner needle tube into a water inlet channel and a water return channel.

[0014] Beneficial effect: A water inlet pipe is provided in the inner needle tube, dividing the inner cavity into a water inlet channel and a water return channel. The water cooling circulation system is used to transport cooling water to the working end of the needle tube and return the cooling water to the cooling water recovery device to circulate and cool the working part of the needle tube.

[0015] Furthermore, the cross-sectional flux of the water inlet channel is larger than that of the water outlet channel, so that the flow rate of the water outlet channel is faster than that of the water inlet channel, and the cold water at the needle tip can be quickly replaced to take away the heat generated at the needle tip.

[0016] Furthermore, the water inlet pipe extends to contact the needle, and cooling water enters from the water inlet pipe to directly cool the needle.

[0017] Furthermore, the tail end of the outer needle tube is fixed by an outer needle tube fixing sleeve, and the tail end of the inner needle tube is fixed by an inner needle tube fixing sleeve, wherein the outer needle tube fixing sleeve is made of insulating material to avoid short circuit between the outer needle tube and the inner needle tube; and the inner needle tube fixing sleeve is made of conductive material.

[0018] Furthermore, the water inlet pipe is processed into a half-cut type or an oblique cut type.

[0019] Furthermore, the outer needle tube is provided with an outer insulating sleeve. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The utility model will be further described below in conjunction with the accompanying drawings.

[0021] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the radiofrequency ablation needle of the utility model.

[0022] Figure 2It is a schematic structural diagram of the inner needle tube of an embodiment of the radiofrequency ablation needle of the present utility model.

[0023] Figure 3 It is a schematic partial structural diagram of an embodiment of the radiofrequency ablation needle of the present utility model.

[0024] Figure 4 It is a schematic partial cooling structural diagram of an embodiment of the radiofrequency ablation needle of the present utility model.

[0025] Figure 5 It is a schematic diagram of the cut of the water inlet pipe of an embodiment of the radiofrequency ablation needle of the present utility model.

[0026] Reference numerals: 1, needle tip; 2, intermediate insulating sleeve; 21, inner needle tube; 3, outer needle tube; 4, outer insulating sleeve; 5, outer needle tube fixing sleeve; 6, inner needle tube fixing sleeve; 7, water outlet tank; 8, water inlet tank; 9, T-type thermocouple; 10, water inlet pipe; 11, bipolar cable; 12, insulating spacer; 22, water inlet channel; 23, return water channel; 71, water outlet; 81, water inlet. Detailed implementation manners

[0027] Next, the technical solutions in the embodiments of the present utility model will be further described in detail with reference to the accompanying drawings in the embodiments of the present utility model.

[0028] As Figures 1-5 shown, this embodiment relates to a bipolar water-cooled circulating radiofrequency ablation needle, which mainly includes a needle tip 1 arranged at the farthest end of the ablation needle; an inner needle tube 21, which is a slender pipe fitting that penetrates through from front to back, and the needle tip 1 is connected to the inner needle tube 21; an outer needle tube 3 sleeved outside the inner needle tube 21, and an insulating spacer 12 is provided between the outer needle tube 3 and the needle tip 1 to form two poles of the bipolar radiofrequency ablation needle; an intermediate insulating sleeve 2 is also provided between the outer needle tube 3 and the inner needle tube 21. When the radiofrequency ablation needle is inserted into the patient's lesion, a loop is formed among the needle tip 1, the lesion tissue, and the outer needle tube 3, so as to perform precise ablation; a water inlet pipe 10 is arranged inside the inner needle tube 21, and the inner cavity of the inner needle tube 21 is divided into a water inlet channel 22 and a return water channel 23. An outer insulating sleeve 4 is sleeved on the surface of the outer needle tube 3, but it should be noted that the exposed area at the left end of the outer needle tube 3 is equal to the exposed area of the inner needle tube 21 to ensure the ablation effect.

[0029] The tail end of the outer needle tube 3 is fixed by an outer needle tube fixing sleeve 5, and the tail end of the inner needle tube 21 is fixed by an inner needle tube fixing sleeve 6, wherein the outer needle tube fixing sleeve 5 is made of insulating material to avoid short circuit between the outer needle tube 3 and the inner needle tube 21; the inner needle tube fixing sleeve 6 is made of conductive material. The inner needle tube fixing sleeve 6 is connected to the water outlet tank 7, and the connection part is kept sealed.

[0030] The inner needle tube 21 and the outer needle tube 3 are stainless steel metal tubes, and the intermediate insulating sleeve 2 and the outer insulating sleeve 4 are high molecular plastic tubes, and their wall thickness is 0.01 mm - 0.1 mm.

[0031] The tail end of the inner needle tube 21 and the tail end of the inner needle tube fixing sleeve 6 are fixedly connected by soldering, and the connection part is kept sealed.

[0032] Two wiring terminals of the bipolar cable 11 are respectively welded to the surface of the tail end of the outer needle tube 3 and the inner needle tube fixing sleeve 6, and the bipolar cable 11 is connected to the radiofrequency main unit. In this way, when the main unit outputs radiofrequency energy, a loop is formed among the exposed part at the left end of the outer needle tube 3, the lesion tissue, and the tip of the inner needle tube 21, so as to perform precise ablation.

[0033] The head of the water inlet pipe 10 is arranged at the tip of the inner needle tube 21, and the tail end is fixed in the water inlet tank 8. The water inlet tank 8 is separated from the water outlet tank 7 and not communicated therebetween. The gap between the water inlet pipe 10 and the inner needle tube 21 forms a water outlet channel.

[0034] In this embodiment, the cooling water enters the water inlet tank 8 from the water inlet 81, flows from the tail end of the water inlet pipe 10 to the inner cavity of the needle tip of the inner needle tube 21, then flows through the water outlet channel formed between the water inlet pipe 10 and the inner needle tube 1 to the water outlet tank 7, and flows out from the water outlet 71 to the cooling water recovery device. During the circulating flow process, the cooling water can effectively cool the working end of the radiofrequency ablation needle and avoid tissue carbonization and adhesion.

[0035] The increase in the flow rate of the fluid will increase the momentum transfer between the fluid and the heat transfer surface, make the boundary layer thinner, and increase the convective heat transfer coefficient, thereby improving the heat transfer efficiency.

[0036] Preferably, the gap between the water inlet pipe 10 and the inner needle tube 21 forms a water outlet channel, and the inner cavity of the inner needle tube 21 forms a water inlet channel 22. The cross-sectional flux of the water inlet channel 22 is greater than that of the water outlet channel 23. The flow rate of the water outlet channel 23 is faster than that of the water inlet channel 22, and the cooling water at the needle tip can be quickly replaced to take away the heat generated at the needle tip 1.

[0037] Preferably, the left end of the water inlet pipe 10 can be processed into a semi-cut type or an inclined cut type (see Figure 5 ) to avoid the difficulty in water outlet caused when the left end of the water inlet pipe 10 abuts against the inner wall of the inner needle tube 21 during the assembly process.

[0038] Preferably, a T-type thermocouple 9 is also arranged in this embodiment to monitor the temperature change during the ablation process in real time. The temperature measuring part of the T-type thermocouple 9 is placed in the cavity of the needle tip of the inner needle tube 21 through the water inlet tank 8 and the water inlet pipe 10 to monitor the water temperature of the working end.

[0039] The above-described embodiments are only a preferred solution of the present utility model, and do not impose any form of limitation on the present utility model. Any person skilled in the technical field, within the technical scope disclosed by the present utility model, making equivalent substitutions or changes according to the technical solution and its concept of the present utility model, shall be covered by the protection scope of the present utility model.

Claims

1. A bipolar water-cooled radiofrequency ablation needle, mainly comprising A needle tip, disposed at the most distal end of the ablation needle; The inner needle tube is a slender tube that runs through the front and back, and the needle head is connected to the inner needle tube; An outer needle tube is sleeved outside the inner needle tube, and an insulating spacer is provided between the outer needle tube and the needle; An intermediate insulating sleeve is also provided between the outer needle tube and the inner needle tube; The water inlet pipe is arranged inside the inner needle tube, and divides the inner cavity of the inner needle tube into a water inlet channel and a water return channel.

2. The bipolar water-cooled radiofrequency ablation needle according to claim 1, characterized in that: The cross-sectional flux of the water inlet channel is greater than that of the water outlet channel.

3. The bipolar water-cooled radiofrequency ablation needle according to claim 1, characterized in that: The water inlet pipe extends and contacts the needle, and cooling water enters from the water inlet pipe to directly cool the needle.

4. The bipolar water-cooled radiofrequency ablation needle according to claim 1, characterized in that: The tail end of the outer needle tube is fixed by an outer needle rod fixing sleeve, and the tail end of the inner needle tube is fixed by an inner needle rod fixing sleeve, wherein the outer needle tube fixing sleeve is made of insulating material, and the inner needle tube fixing sleeve is made of conductive material.

5. The bipolar water-cooled radiofrequency ablation needle according to claim 1, characterized in that: The water inlet pipe is processed into a half-cut type or an oblique cut type.

6. The bipolar water-cooled radiofrequency ablation needle according to claim 1, characterized in that: The outer needle tube is sleeved with an outer insulating sleeve.

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