Varicosity microwave ablation catheter and temperature measurement method and system

Abstract

The invention relates to a varicosity microwave ablation catheter. The varicosity microwave ablation catheter comprises a catheter head end, a catheter body connected with the catheter head end and a radiation unit located in the catheter body. A metal clamping sleeve is arranged between the catheter body and the catheter head end, and a radiation window with a preset distance is arranged between the metal clamping sleeve and the catheter head end and used for radiating energy. A temperature thermocouple is arranged between the metal clamping sleeve and the radiation unit, and the thermocouple is tightly connected with the metal clamping sleeve. The temperature of the head end of the varicosity ablation catheter can be monitored in real time, and normal tissue is prevented from being damaged due to too high temperature.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a varicose vein microwave ablation catheter, a temperature measurement method and a system. Background Art

[0002] Varicose veins of the lower extremities are common vascular surgical diseases in clinical general surgery. They are clinical symptoms of chronic venous dysfunction of the lower extremities, caused by reflux due to venous valve insufficiency. Varicose veins of the lower extremities are also called chronic venous insufficiency of the lower extremities, which include two types: varicose veins of the lower extremities and deep venous valve insufficiency.

[0003] Early varicose vein radiators only had laser positioning for treatment, such as the product with patent 200620042485.1; the varicose vein treatment device with cold circulation with patent 200820160703.0 proposed the concept of cold circulation, but the microwave radiator used in it had a sharp head, which was prone to improper human operation during use, and was not conducive to insertion into a vein more than 1 meter long for treatment, especially at the bifurcation of the blood vessels, where it was more likely to pierce the blood vessels and tissues; later, the varicose vein electrode with a round head temperature control design with patent 201610743978.6 appeared. During actual surgical use, the cable of the electrode would be too hot and had to be switched intermittently to prevent the high temperature from burning healthy human tissues during microwave treatment, while protecting the electrode from damage; when using varicose vein microwave ablation catheters for treatment, the head temperature is difficult to monitor, and how to accurately monitor the head temperature is the main problem currently faced in this field. Summary of the invention

[0004] The purpose of the present invention is to provide a varicose vein ablation catheter with accurate temperature measurement, which can monitor the temperature of the catheter tip in real time to prevent excessive temperature from damaging normal tissue.

[0005] To achieve the above-mentioned purpose, the present invention provides a technical solution 1, comprising a catheter head end, a catheter body connected to the catheter head end, and a radiation unit located inside the catheter body; A metal ferrule is provided between the catheter body and the catheter head end, and a radiation window with a preset distance is provided between the metal ferrule and the catheter head end for radiating energy; A temperature measuring thermocouple is arranged between the metal ferrule and the radiation unit, and the thermocouple is in close contact with the metal ferrule.

[0006] The technical effect of the first technical solution of the present invention is: by installing a temperature measuring thermocouple between the metal ferrule and the radiation unit, the temperature measuring thermocouple and the metal ferrule are in close contact, and the metal has a fast heat transfer speed, so the temperature of the front end of the catheter can be accurately measured.

[0007] To achieve the above-mentioned purpose, the second technical solution provided by the present invention is to include a catheter head end, a catheter body connected to the catheter head end, and a radiation unit located inside the catheter body; A metal ferrule is provided between the catheter body and the catheter head end, and a radiation window with a preset distance is provided between the metal ferrule and the catheter head end for radiating energy; The metal ferrule is configured to limit part of the radiation energy of the radiation unit; A temperature measuring thermocouple is arranged between the metal ferrule and the radiation unit, and the thermocouple is in close contact with the metal ferrule.

[0008] The technical effect of the second technical solution of the present invention is: the present invention uses a metal ferrule to limit the range of radiation to prevent thermal damage caused by excessive radiation range. Part of the radiation energy acts on the metal, causing the metal to heat up rapidly, and the other part of the energy radiated through the radiation window is absorbed by the tissue. The heating rate of the metal is slightly faster than the tissue temperature, so a temperature measuring thermocouple is provided between the metal ferrule and the radiation unit. The thermocouple and the metal ferrule are in close contact, and the metal has fast heat transfer and can quickly and accurately measure the temperature of the catheter tip.

[0009] Furthermore, the preset position of the thermocouple is outside the radiation energy range of the radiation window.

[0010] Furthermore, a cooling water inlet channel and a cooling water outlet channel are provided inside the catheter body, and the preset position of the thermocouple is far away from the farthest distance of cooling water cooling.

[0011] The purpose of the present invention is to provide a temperature measurement method for a varicose vein ablation catheter with accurate temperature measurement, so as to monitor the temperature of the catheter tip in real time and prevent the temperature from being too high and damaging normal tissue.

[0012] To achieve the above-mentioned purpose, the third technical solution provided by the present invention is to include a catheter head end, a catheter body connected to the catheter head end, and a radiation unit located inside the catheter body; A metal ferrule is provided between the catheter body and the catheter head end, and a radiation window with a preset distance is provided between the metal ferrule and the catheter head end for radiating energy; A temperature measuring thermocouple is provided between the metal ferrule and the radiation unit, and the thermocouple is in close contact with the metal ferrule; Part of the radiation energy of the radiation unit acts on the metal ferrule and is received by the thermocouple through heat transfer.

[0013] Furthermore, the host receives the temperature signal of the thermocouple and adjusts the power output.

[0014] The purpose of the present invention is to provide a varicose vein ablation system with accurate temperature measurement, which monitors the temperature of the catheter tip in real time to prevent excessive temperature from damaging normal tissue.

[0015] To achieve the above-mentioned purpose, the fourth technical solution provided by the present invention is a varicose vein ablation system, comprising a host and a varicose vein ablation catheter coupled to the host, the varicose vein ablation catheter comprising a catheter head, a catheter body connected to the catheter head, and a radiation unit located inside the catheter body; a metal ferrule is provided between the catheter body and the catheter head, and a radiation window with a preset distance between the metal ferrule and the catheter head is provided for radiating energy; a temperature measuring thermocouple is provided between the metal ferrule and the radiation unit, and the thermocouple is in close contact with the metal ferrule.

[0016] Furthermore, the metal ferrule may be configured to limit a portion of the radiation energy of the radiation unit, and the portion of the radiation energy is transmitted to the host through heat transfer. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the front end structure of the varicose vein microwave ablation catheter of the present invention.

[0018] Figure 2 It is a cross-sectional schematic diagram of the water-cooling structure of the varicose vein microwave ablation catheter of the present invention.

[0019] Figure 3 It is a schematic diagram of the handle of the varicose vein microwave ablation catheter of the present invention.

[0020] Figure 4 It is a schematic diagram of the overall structure of the varicose vein microwave ablation catheter of the present invention.

[0021] Figure 5 This is a comparison diagram of the varicose vein microwave ablation catheter experiment of the present invention.

[0022] 1-ablation catheter, 2-scale, 3-handle, 10-catheter head, 11-PTFE bushing, 12-metal ferrule, 13-coaxial cable, 14-thermocouple, 15-thermocouple wire, 16-step portion, 17-cooling water outlet, 18-radiation antenna, 20-cooling water inlet pipe, 21-catheter body, 22-tail metal ferrule, 23-water outlet box, 24-water inlet box, 25-water outlet pipe joint, 26-water inlet pipe joint, 27-temperature measuring joint, 28-microwave joint, 29-water isolating ring, 31-microwave cable, 32-microwave connector, 33-temperature measuring connector, 34-water outlet pipe, 35-water inlet pipe. DETAILED DESCRIPTION

[0023] In order to further understand the content of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings.

[0024] The principle of microwave radiation treatment of diseased areas is to use microwave high-frequency electromagnetic waves to raise the temperature of tissues, thereby achieving the purpose of treating diseased tissues.

[0025] The basic properties of microwaves are usually presented as penetration, reflection, and absorption. For glass, plastic, and porcelain, microwaves almost pass through without being absorbed. For water and food, they absorb microwaves and heat themselves. For metal objects, microwaves are reflected.

[0026] Embodiment 1 The technical solution 1 of the present invention provides Figure 1 A varicose vein catheter as shown in the drawing comprises a catheter tip 10, an elongated catheter body 21 and a radiation unit located inside the catheter body 21.

[0027] A metal ferrule 12 is provided between the catheter body 21 and the catheter head end 10, and a polyfluoroethylene bushing 11 is installed between the metal ferrule 12 and the catheter head end 10 to form a radiation window with a preset distance for radiating microwave energy; the polyfluoroethylene bushing 11 is installed on the cylinder at the tail end of the catheter head end 10, and the radiation unit includes a radiation antenna 18 and a coaxial cable 13, and the radiation antenna 18 is installed in a through hole on the cylinder at the tail end of the round-headed catheter head end 10.

[0028] A temperature measuring thermocouple 14 is provided between the metal ferrule 12 and the radiation unit. The temperature measuring thermocouple 14 is in close contact with the metal ferrule 12. The metal ferrule 12 has a fast heat transfer speed, so that the temperature of the front end of the catheter can be accurately measured.

[0029] Optionally, the temperature measurement of the thermocouple 14 is affected by many factors, among which electromagnetic waves will have a greater impact on the data collected by the thermocouple 14, so the thermocouple 14 is preset outside the radiation energy range of the radiation window.

[0030] Optional, such as Figure 2 , Figure 3 The ablation catheter shown also includes a cooling water inlet pipe 20, a catheter body 21, and a metal ferrule 22 at the tail of the catheter body 21; the front end of the cooling water inlet pipe 20 is fixedly connected to the cylindrical step portion 16 of the metal ferrule 12 at the front end of the catheter body 21, and the cylindrical step portion 16 is sealed with the coaxial cable 13, so that the cooling water cannot contact the thermocouple 14. One end of the catheter body 21 is mounted on the barbed tube at the tail of the front metal ferrule 12, and the other end is mounted on the tail metal ferrule 22, and they are fixed with high-temperature glue respectively. A cooling water outlet channel is formed between the catheter body 21 and the cooling water inlet pipe 20, and the preset position of the thermocouple 14 is far away from the farthest distance of cooling water cooling to prevent the cooling water from affecting the thermocouple 14.

[0031] like Figure 3As shown, the handle includes a water outlet box 23, a water inlet box 24, a water outlet pipe joint 25, a water inlet pipe joint 26, a temperature measuring joint 27, and a microwave joint 28; the front end of the water outlet box 23 is welded and fixed to the tail metal ferrule 22; a water isolating ring 29 is provided at the front end of the water inlet box 24 and the rear end of the water outlet box 23, and a water isolating and fixed connection is made with the outer wall of the rear end of the cooling water inlet pipe 20 at the water isolating ring 29; the water outlet pipe joint 25 is connected to the water outlet box 23, the water inlet pipe joint 26 is connected to the water inlet box 24, the temperature measuring joint 27 is connected to the temperature measuring thermocouple 14 through an extremely fine thermocouple wire 15, and the microwave joint 28 is connected to the coaxial cable 13.

[0032] The cooling water inlet pipe 20 of the present invention has three cooling water outlets 17 on the side of the front end. The cooling water flows from the water inlet pipe joint 26 into the water inlet tank 24, flows into the cooling water inlet pipe 20, flows out from the three cooling water outlets 17, flows into the water outlet tank 23 along the inner hole of the catheter body 21, and then flows out from the water outlet pipe joint 25. The cold circulation water circuit structure design of the present invention, wherein the cooling water inlet pipe 20 and the catheter body 21 are made of high temperature resistant non-metallic materials, and a double insulation design is performed in terms of materials and structure, which avoids the problem of temperature conduction during microwave treatment causing the needle rod to overheat, the patient to be unable to bear the pain due to excessively high temperature, or even burning normal human tissue, and can also prevent the electrode from being easily damaged due to excessive temperature.

[0033] The engineering plastics used for the cooling water inlet pipe 20 and the catheter body 21 in the present invention have good electrical insulation properties, excellent high temperature resistance, impact resistance and chemical stability. The properties of the thermoplastic elastomer material of the cooling water inlet pipe 20 and the catheter body 21 make the microwave ablation catheter of the present invention have good flexibility and bendability, making it easier to establish venous access during the treatment process.

[0034] Of course, the cooling water inlet pipe 20 in the present invention can also be replaced by a capillary tube as a water inlet pipe.

[0035] The coaxial cable 13 in the present invention is built into the cooling water inlet pipe 20 , and the cooling water inlet pipe 20 and the ultra-fine thermocouple wire 15 are built into the catheter body 21 .

[0036] like Figure 4 As shown, the varicose vein ablation catheter of the present invention comprises an ablation catheter 1, a scale 2 on the ablation catheter 1 and a handle 3. The cooling water inlet pipe 20 of the present invention is a PTFE tube, the catheter body 21 is a PA12 nylon tube, and the length of the ablation catheter 1 exposed outside the handle is 1 meter.

[0037] The microwave connector 28 and the temperature measuring connector 27 are output through a microwave cable 31 and connected to a host (not shown in the figure) through a microwave connector 32 and a temperature measuring connector 33 on the cable.

[0038] After the water outlet pipe joint 25 is externally connected to the water outlet pipe 34 and the water inlet pipe joint 26 is externally connected to the water inlet pipe 35, the water pipes are connected to the main unit end.

[0039] The front end of the microwave ablation catheter in the present invention is sprayed with a Teflon coating, which increases the lubrication effect of the catheter during the puncture process and plays an anti-sticking role during the high-temperature ablation process.

[0040] The temperature measuring thermocouple of the microwave ablation catheter in the present invention performs temperature acquisition control, which solves the problem of needing intermittent ablation treatment due to excessive temperature. The effective temperature control of the guide tip is combined with the cold circulation design, so the doctor can perform continuous ablation during the treatment process, which reduces the treatment time and improves the treatment efficiency.

[0041] Embodiment 2 The second technical solution of the present invention provides Figure 1 A varicose vein catheter is shown. It should be noted that the technical solution 2 of the present invention is a further improvement on the technical solution 1, and the same parts will not be repeated.

[0042] The catheter comprises a catheter head end 10 , an elongated catheter body 21 and a radiation unit located inside the catheter body 21 .

[0043] A metal ferrule 12 is provided between the catheter body 21 and the catheter head end 10, and a polytetrafluoroethylene bushing 11 is installed between the metal ferrule 12 and the catheter head end 10 to form a radiation window with a preset distance for radiating energy; the polytetrafluoroethylene bushing 11 is installed on the cylinder at the tail of the catheter head end 10, and the radiation unit includes a radiation antenna 18 and a coaxial cable 13, and the radiation antenna 18 is installed in the through hole on the cylinder at the tail of the round-headed catheter head end 10. Figure 1 As shown, the radiating antenna 18 is partially wrapped by the metal ferrule 12 to limit part of the radiated energy of the radiating antenna 18; Microwaves are used to directly act on the venous cavity wall, so that it can instantly generate a high temperature with certain penetration in a small range to coagulate the tissue, and then cause the venous cavity wall tissue to degenerate and shrink, gradually fibrosis, and finally completely close, so as to achieve the purpose of treatment; however, to treat in such a small range, it is necessary to control the radiation range of microwaves and the temperature of the catheter tip, and use the metal ferrule 12 to limit the radiation range to prevent thermal damage. In addition, part of the radiation energy acts on the metal, causing the metal to heat up rapidly, and the other part of the energy radiated through the radiation window is absorbed by the tissue. The heating rate of the metal is slightly faster than the tissue temperature, so at this time, a temperature measuring thermocouple 14 is provided between the metal ferrule 12 and the radiation unit. The thermocouple 14 is in close contact with the metal ferrule 12, and the temperature of the catheter tip can be measured quickly and accurately.

[0044] Optionally, the temperature measurement of the thermocouple 14 is affected by many factors, among which electromagnetic waves will have a greater impact on the data collected by the thermocouple 14, so the thermocouple 14 is preset outside the radiation energy range of the radiation window.

[0045] Embodiment 3 The third technical solution of the present invention provides a method for measuring the temperature of a varicose vein catheter, such as Figure 1 As shown, it includes a catheter head end 10, an elongated catheter body 21 and a radiation unit located inside the catheter body 21; A metal ferrule 12 is provided between the catheter body 21 and the catheter head end 10, and a radiation window with a preset distance is provided between the metal ferrule 12 and the catheter head end 10 for radiating energy; A temperature measuring thermocouple 14 is provided between the metal ferrule 12 and the radiation unit, and the thermocouple 14 is in close contact with the metal ferrule 12; Part of the radiation energy of the radiation unit acts on the metal ferrule 12 and is received by the thermocouple 14 through heat transfer. The received signal is transmitted to the host, and the host adjusts the power output after receiving the signal.

[0046] Embodiment 4 like Figure 1-4 As shown, technical solution four of the present invention provides a varicose vein system, including a host and a varicose vein ablation catheter 1 coupled to the host, the varicose vein ablation catheter 1 including a catheter head 10, an elongated catheter body 21 and a radiation unit located inside the catheter body 21; a metal ferrule 12 is provided between the catheter body 21 and the catheter head 10, and a radiation window with a preset distance between the metal ferrule 12 and the catheter head 10 is provided for radiating energy; a temperature measuring thermocouple 14 is provided between the metal ferrule 12 and the radiation unit, and the thermocouple 14 and the metal ferrule 12 are in close contact.

[0047] Optionally, the metal ferrule 12 may be configured to limit a portion of the radiation energy of the radiation unit, and the portion of the radiation energy is transmitted to the host through heat transfer.

[0048] It should be noted that the microwave host in the present invention is a prior art and may be a host developed by Yigao itself, which will not be described in detail here.

[0049] experiment Figure 5 A comparison chart of test experimental data of a microwave ablation catheter developed using the technical solution provided by the present invention.

[0050] Test method: Connect the main unit and microwave ablation catheter, place the catheter in a constant temperature water bath, test the accuracy of catheter data collection at powers of 40W, 50W and 60W, and use an infrared thermal imager to measure the temperature at the center of the radiation window.

[0051] In the figure, the horizontal axis represents time (seconds), the vertical axis represents temperature, and the window temperature (rod temperature) represents the temperature collected by the thermocouple.

[0052] As can be seen from the figure, the data collected by the thermocouple set in the microwave ablation catheter is relatively accurate, and there is no large fluctuation in the temperature rise process. The temperature measured by the infrared thermal imager is slightly higher than the temperature collected by the thermocouple in the catheter, but in the end the temperature collected by the thermocouple and the temperature measured by the infrared thermal imager will be consistent.

[0053] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A varicose vein microwave ablation catheter, characterized in that: It comprises a catheter head end, a catheter body connected to the catheter head end, and a radiation unit located inside the catheter body; A metal ferrule is provided between the catheter body and the catheter head end, and a radiation window with a preset distance is provided between the metal ferrule and the catheter head end for radiating energy; A temperature measuring thermocouple is arranged between the metal ferrule and the radiation unit, and the thermocouple is in close contact with the metal ferrule.

2. A varicose vein microwave ablation catheter, characterized in that: It comprises a catheter head end, a catheter body connected to the catheter head end, and a radiation unit located inside the catheter body; A metal ferrule is provided between the catheter body and the catheter head end, and a radiation window with a preset distance is provided between the metal ferrule and the catheter head end for radiating energy; The metal ferrule is configured to limit part of the radiation energy of the radiation unit; A temperature measuring thermocouple is arranged between the metal ferrule and the radiation unit, and the thermocouple is in close contact with the metal ferrule.

3. The varicose vein microwave ablation catheter according to claim 1 or 2, characterized in that: The preset position of the thermocouple is outside the radiation energy range of the radiation window.

4. The varicose vein microwave ablation catheter according to claim 1 or 2, characterized in that: A cooling water inlet channel and a cooling water outlet channel are also provided inside the conduit body, and the preset position of the thermocouple is far away from the farthest distance of cooling water cooling.

5. A method for measuring temperature of a varicose vein microwave ablation catheter, characterized in that: It comprises a catheter head end, a catheter body connected to the catheter head end, and a radiation unit located inside the catheter body; A metal ferrule is provided between the catheter body and the catheter head end, and a radiation window with a preset distance is provided between the metal ferrule and the catheter head end for radiating energy; A temperature measuring thermocouple is provided between the metal ferrule and the radiation unit, and the thermocouple is in close contact with the metal ferrule; Part of the radiation energy of the radiation unit acts on the metal ferrule and is received by the thermocouple through heat transfer.

6. The temperature measurement method of varicose vein microwave ablation catheter according to claim 5, characterized in that: The host receives the temperature signal from the thermocouple and adjusts the power output.

7. A varicose vein microwave ablation system, characterized in that: It includes a host and a varicose vein ablation catheter coupled to the host, the varicose vein ablation catheter includes a catheter head, a catheter body connected to the catheter head, and a radiation unit located inside the catheter body; a metal ferrule is provided between the catheter body and the catheter head, and a radiation window with a preset distance between the metal ferrule and the catheter head is provided for radiating energy; a temperature measuring thermocouple is provided between the metal ferrule and the radiation unit, and the thermocouple is in close contact with the metal ferrule.

8. The varicose vein system according to claim 7, characterized in that: The metal ferrule may be configured to limit a portion of the radiation energy of the radiation unit, and the portion of the radiation energy is transmitted to the host by heat transfer.

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