Varicose vein ablation catheter, ablation monitoring system and ablation range measurement method

Abstract

This invention discloses a varicose vein ablation catheter, including a catheter body, a radiation component, a temperature measuring component, a connecting component, and a control unit. The radiation component is disposed on the catheter body and connected to a semi-rigid coaxial cable inside the catheter body. The temperature measuring component is disposed inside the catheter body, close to the radiation component, and measures the temperature inside and outside the radiation area of ​​the radiation component to assist in determining the length of a single ablation session. Advantages: By utilizing three spaced microwave tubes disposed on the catheter body to form three overlapping ablation radiation zones, all three radiation zones can be ablated simultaneously during a single ablation session, enhancing the length of a single ablation session and improving ablation efficiency. The ablation temperature is measured during the ablation process using temperature measuring couplers disposed within and outside the radiation zones, ensuring the ablation effect while the control unit automatically generates a temperature rise curve based on the temperature at different locations, thereby automatically calculating the length of a single ablation session.

Description

Technical Field

[0001] This invention specifically relates to a varicose vein ablation catheter, an ablation monitoring system, and a method for measuring the ablation range. Background Technology

[0002] Varicose veins of the lower extremities are one of the most common diseases of the cardiovascular system, with an incidence rate of over 15% in Chinese adults and 30%-40% in people over 50 years of age. The main clinical manifestations include: dilation and tortuosity of superficial veins in the lower extremities, heaviness and weakness in the lower extremities, and mild swelling of the ankle and trophic changes in the skin of the foot and boot area, such as pigmentation, dermatitis, eczema, subcutaneous lipid sclerosis, and ulcers. Some patients may develop superficial vein thrombosis. According to the CEAP clinical classification, surgical treatment is recommended for patients with simple great / small saphenous vein varicose veins of grade C2 or above, symptomatic varicose veins, and those with moderate to severe clinical manifestations of chronic lower extremity venous insufficiency.

[0003] Common surgical procedures include: high ligation and stripping of the great / small saphenous vein, endovenous closure of superficial veins, and sclerotherapy. Among them, endovenous closure of superficial veins has become the mainstream surgical procedure due to its ability to achieve the same clinical efficacy as traditional surgery, while also having advantages such as short operation time, fast recovery, and minimally invasive and aesthetically pleasing results. It accounts for more than 80% of varicose vein surgeries in tertiary hospitals.

[0004] Endovascular closure of superficial veins mainly utilizes three energy sources: radiofrequency, microwave, and laser. Microwave therapy works by generating heat through molecular vibration and friction within the tissue, causing damage, coagulation, and closure of the blood vessel wall, ultimately leading to fibrosis. Compared to laser and radiofrequency, it offers advantages such as high thermal efficiency, rapid heating, uniform tissue heating, moderate heat penetration, and controllable coagulation range. Furthermore, it avoids ultrasound interference, and the ablation effect is unaffected by impedance.

[0005] The average length of the human great saphenous vein is 76.52 cm. The conventional surgical treatment area is from near the knee joint to the groin, with a length ranging from 30 to 50 cm. Currently, microwave ablation catheters all use a single microwave radiation antenna. The length of a single ablation varies depending on the thickness of the blood vessel, the duration of action, and the amount of surrounding swelling fluid injected, ranging from 1 to 1.5 cm. It is impossible to confirm the actual ablation length. To avoid missed ablation, the ablation is withdrawn every 1 cm. However, microwaves have high thermal efficiency, and overlapping areas may experience carbonization after two ablations, increasing the risk of local thermal damage and prolonging postoperative recovery time. To accurately confirm the length of a single ablation, a CT scan of the ablation site is needed after ablation to determine the length of the single ablation. This method is relatively cumbersome and inconvenient to use.

[0006] In addition, microwave ablation has an efficiency of 1cm / 4-6s and requires 30-50 needle withdrawals during the procedure. Compared to radiofrequency ablation, which has an efficiency of 7cm / 20s per ablation and requires 6-7 needle withdrawals during the procedure, the operation takes longer and is more complicated.

[0007] Therefore, a multi-point microwave ablation catheter with temperature measurement function is needed. This catheter can not only be used to treat varicose veins in the lower extremities, but also improve surgical efficiency, calculate ablation length, and reduce surgical complications.

[0008] Chinese patent CN202120733837.2, entitled "Microwave Ablation Catheter and Microwave Therapy Device Thereof", describes a device that includes a guidewire, a guidewire hole in the microwave ablation catheter, and is inserted through the skin into a varicose vein. The guidewire travels within the guidewire hole, extending the lumen of the tortuous varicose vein and guiding the microwave ablation catheter to a designated position.

[0009] As shown in the attached figure of patent CN202120733837.2, this patent is for a traditional microwave ablation catheter, which has only one radiation head and does not have the ability to calculate the ablation length. Summary of the Invention

[0010] The first technical problem to be solved by the present invention is the low ablation efficiency of existing microwave catheters mentioned in the background art.

[0011] The second technical problem to be solved by the present invention is how to select the ablation range.

[0012] The third technical problem to be solved by the present invention is the problem of unclear single ablation length of existing microwave catheters mentioned in the background art.

[0013] To solve the first technical problem mentioned above, a varicose vein ablation catheter is proposed; it is achieved through the following technical solution: a varicose vein ablation catheter, including a catheter body, with an operating handle at one end of the catheter body, characterized in that: it further includes a radiation component, a temperature measuring component, a connecting component, and a control unit. The radiation component is mounted on the catheter body via the connecting component and is connected to a semi-rigid coaxial cable inside the catheter body. The temperature measuring component is located inside the catheter body, close to the radiation component, and measures the temperature inside and outside the radiation area of ​​the radiation component. The control unit, connected to both the radiation component and the temperature measuring component, is simultaneously connected to a computer. The control unit controls the power of the radiation component and generates a temperature curve on the computer based on the temperature measured by the temperature measuring component to determine the single ablation length.

[0014] In a preferred embodiment of the present invention, the radiation component includes a microwave head, which forms a radiation region on the catheter body. The microwave head includes a first microwave tube, a second microwave tube, and a third microwave tube. The first microwave tube is disposed at the end of the catheter body to form a first radiation region. The second microwave tube is connected to the first microwave tube through a connecting component, and the two are spaced apart to form a second radiation region. The third microwave tube is connected to the second microwave tube through a connecting component, and the two are spaced apart to form a third radiation region.

[0015] The first, second, and third radiation zones are spaced apart from each other, and their radiation ranges overlap at the edges. The arrangement of multiple radiation zones allows the ablation catheter to ablate three areas simultaneously, increasing the length of a single ablation and improving ablation efficiency.

[0016] In a preferred embodiment of the present invention, the temperature measuring component includes an in-radiation thermocouple and an out-of-radiation thermocouple. The in-radiation thermocouple is located in the radiation zone at the front of the catheter body, and the out-of-radiation thermocouple is located in the radiation zone at the rear of the catheter body, outside the microwave head radiation area at the rear. The temperature measuring component is convenient for measuring the ablation temperature, for judging the ablation effect and the length of a single ablation, and is easy to use.

[0017] In a preferred embodiment of the present invention, the thermocouple in the radiation zone includes a first thermocouple, a second thermocouple, and a third thermocouple. The first thermocouple is disposed inside the conduit body at the point where it overlaps with the radiation edges of the first and second radiation zones. The second thermocouple is disposed inside the conduit body at the point where it overlaps with the radiation edges of the second and third radiation zones. The third thermocouple is disposed inside the conduit body near the middle of the third radiation zone.

[0018] The thermocouples outside the radiation zone include a fourth thermocouple and a fifth thermocouple. The fourth thermocouple is located at the edge of the third radiation zone on the main body of the conduit, and the fifth thermocouple is located outside the third radiation zone. The distance between the fifth thermocouple and the fourth thermocouple is the same as the distance between the fourth thermocouple and the third thermocouple. The placement of thermocouples at the overlapping edge of the two radiation zones facilitates temperature monitoring of the ablation area and also prevents incomplete ablation in the overlapping area. The placement of the fourth and fifth thermocouples at the outermost radiation zone allows them to work together with the third thermocouple to measure the temperature of the outermost radiation zone and the area outside the radiation zone, making it easier to determine the single ablation distance through temperature.

[0019] In a preferred embodiment of the present invention, the connecting component includes a connecting slot, one end of which is provided with a connecting groove and the other end with a connecting head. The connecting groove can be fixed to the end of the microwave head, and the connecting head can be inserted into the conduit body. The connecting component facilitates the connection of the microwave head and the conduit body.

[0020] In a preferred embodiment of the present invention, an outer sleeve is fitted over the front end of the radiation assembly mounted on the catheter body. The outer sleeve is disconnected near the microwave head on the radiation assembly, leaving the microwave head for microwave ablation exposed. This arrangement prevents the outer sleeve from blocking the microwave head and affecting the microwave ablation effect.

[0021] To address the second technical problem mentioned above, this invention also discloses an ablation monitoring system for varicose vein ablation catheters, comprising a microwave ablation device and a temperature monitoring device. The microwave ablation device is configured to provide microwave energy to the microwave ablation catheter, and the temperature monitoring device displays a temperature rise curve and adjusts the ablation power and ablation time according to the temperature rise curve.

[0022] In a preferred embodiment of the present invention, the temperature monitoring device also stores temperature information and corresponding ablation information. The ablation information includes ablation power, time, and corresponding ablation major and minor diameters. This setting allows the ablation power and ablation time to be adjusted in a timely manner based on the temperature rise curve and clinical data, preventing over-ablation and thermal damage.

[0023] To address the third technical problem mentioned above, this invention also discloses a method for measuring the single ablation length of a varicose vein ablation catheter, characterized by the following steps:

[0024] Step 1, Catheter Placement: Under ultrasound guidance, the catheter body is inserted through the vascular sheath into the great saphenous vein, and an anesthetic tumescent solution is injected locally;

[0025] Step 2: Set ablation parameters: Determine the ablation power based on the ablation location, and use the control unit to set the ablation power and ablation duration;

[0026] Step 3: Temperature rise curve generation: The temperature measuring component feeds back the temperature values ​​of the five thermocouples and generates temperature rise curves of the five thermocouples during the ablation process on the computer.

[0027] Step 4: Determine the single ablation length: Based on the temperature readings and temperature rise curves from the five thermocouples fed back by the temperature sensing components, calculate the single ablation length using the formula M=L1+L2+L3-LY+LX.

[0028] In the formula:

[0029] M represents the total length of a single ablation session;

[0030] L1 is the length of the first radiation zone;

[0031] L2 is the length of the second radiation zone;

[0032] L3 is the length of the third radiation zone;

[0033] LX is the distance from the ablation end to the third radiation zone;

[0034] LY is the total overlap length of the radiation region;

[0035] Step 5: Once a single ablation is complete, withdraw the needle according to the length of the ablation, and continue ablation until it is completely completed.

[0036] In a preferred embodiment of the present invention, in the formula M=L1+L2+L3+LX-LY, the lengths of L1, L2, L3 and LY are constants, and the length of LX is automatically calculated based on the temperature rise curve. This setting facilitates the determination of the ablation end position based on the temperature value on the temperature curve, facilitates the automatic calculation of the single ablation length, is convenient to use, and improves ablation efficiency.

[0037] The beneficial effects of this invention compared to the prior art are:

[0038] The technical solution of this invention utilizes three microwave tubes spaced apart on the main body of the conduit to form three overlapping ablation radiation zones. During a single ablation, the three radiation zones can be ablated simultaneously, enhancing the single ablation length and improving ablation efficiency. Furthermore, it uses thermocouples located within and outside the ablation radiation zones to measure the ablation temperature during the ablation process. This ensures the ablation effect while automatically generating temperature rise curves based on the temperature at different locations, thereby automatically calculating the single ablation length. This method is convenient to use and solves the problems of low ablation efficiency and unclear single ablation length mentioned in the background art of existing microwave conduits. Attached Figure Description

[0039] Figure 1 This is a three-dimensional schematic diagram of the present invention;

[0040] Figure 2 This is a three-dimensional schematic diagram of the front ablation end of the present invention (excluding the outer sheath);

[0041] Figure 3 This is a partial cross-sectional view of the front ablation end of the present invention;

[0042] Figure 4 This is a schematic diagram of the radiation zone distribution of the present invention;

[0043] Figure 5 This is an exploded view of the front ablation end of the present invention;

[0044] Figure 6 This is a table showing the ablation temperature at different ablation times under 60W power according to the present invention;

[0045] Figure 7 This is a temperature rise curve of the present invention at a power of 60W;

[0046] Figure 8 This is a flowchart illustrating the ablation process and ablation length calculation of the present invention;

[0047] Explanation of reference numerals in the attached drawings: 1-Conduit body, 11-Semi-rigid coaxial cable, 12-Microwave needle, 13-Outer sheath, 2-Radiation assembly, 21-First microwave tube, 22-Second microwave tube, 23-Third microwave tube, 24-Connector, 25-First radiation zone, 26-Second radiation zone, 27-Third radiation zone, 28-Connecting tube, 3-Temperature measuring assembly, 31-First thermocouple, 32-Second thermocouple, 33-Third thermocouple, 34-Fourth thermocouple, 35-Fifth thermocouple, 4-Connecting assembly, 41-Connecting bracket, 42-Connecting slot, 5-Operating handle, 51-Power interface. Detailed Implementation

[0048] The following will refer to the appendices in the embodiments of the present invention. Figure 1-8 The technical solutions in the embodiments of the present invention will be described in detail below. Example

[0049] like Figure 1 , 2 As shown in Figure 3, a varicose vein ablation catheter includes a catheter body 1, a radiation component 2, a temperature measuring component 3, and a connecting component 4. The end of the catheter body 1 is provided with an operating handle 5 for easy hand-holding. The radiation component 2 for emitting ablation microwaves is provided at the front end of the catheter body 1. The temperature measuring component 3 for temperature measurement is provided inside the catheter body 1. The connecting component 4 is provided on the catheter body 1 and connects the catheter body 1 and the radiation component 2.

[0050] The catheter body 1 is a hollow tube made of existing PEEK material. Its main function is to serve as the main body of the microwave ablation catheter, and also as a carrier for the installation of radiation components and temperature measurement components. An operating handle 5 is fixedly connected to one end of the catheter body 1, and the operator can operate it through the operating handle 5.

[0051] The main function of the radiating component 2 is to act as a radiating antenna to generate microwaves at frequencies such as 915MHz or 2450MHz in order to achieve the purpose of ablation.

[0052] The main function of the temperature measuring component 3 is to measure the temperature of each radiation zone in the radiation component 2, as well as the temperature of the edge and outside of the last radiation zone, so as to facilitate real-time control of the ablation effect and assist in calculating the ablation range of a single operation by means of the ablation temperature.

[0053] The main function of the connecting component 4 is to connect the microwave tube and the conduit body 1 in the radiation component 2, so as to facilitate the fixation of the microwave tube.

[0054] The main function of the control unit is to adjust the ablation power of each microwave tube in the radiation component 2, control the ablation time of each microwave tube, and also receive the ablation temperature monitored by the temperature measuring component 3. It generates a time-temperature table using the ablation temperature and ablation time, fits the temperature rise curve using the time-temperature table, and finally determines the endpoint position of a single ablation based on the temperature rise curve, thereby calculating the length of a single ablation.

[0055] like Figure 2 , 3 As shown in Figures 4 and 5, the radiation assembly 2 includes a microwave head and a radiation zone composed of the microwave head.

[0056] The microwave head includes a first microwave tube 21, a second microwave tube 22, and a third microwave tube 23. The first microwave tube 21, the second microwave tube 22, and the third microwave tube 23 are existing ablation electrodes, and their overall shape is cylindrical. The outer diameter of the first microwave tube 21, the second microwave tube 22, and the third microwave tube 23 is the same as the outer diameter of the catheter body 1. The first microwave tube 21, the second microwave tube 22, and the third microwave tube 23 are combined with a semi-rigid coaxial cable 11 that runs through the catheter body 1. The first microwave tube 21, the second microwave tube 22, and the third microwave tube 23 are powered through the semi-rigid coaxial cable 11 to generate microwaves, thereby achieving the purpose of ablation.

[0057] In this embodiment, the semi-rigid coaxial cable 11 is preferably an SFT50-1 semi-steel coaxial RG407 metal microwave feeder. The semi-rigid coaxial cable 11 is inserted through the operating handle at the end of the conduit body 1 and connected to the first microwave tube 21 at the front end of the conduit body 1. In order to facilitate power supply to the semi-rigid coaxial cable 11, the end of the semi-rigid coaxial cable 11 is connected to the power interface 51 fixed to the operating handle 5.

[0058] To facilitate the connection and fixation of the first microwave tube 21, the second microwave tube 22, and the third microwave tube 23, a circular boss protrudes from the circular end face at both ends of the first microwave tube 21, the second microwave tube 22, and the third microwave tube 23. This boss is named connector 24. The outer diameter of connector 24 is the same as the inner diameter of the conduit body 1. The first microwave tube 21, the second microwave tube 22, and the third microwave tube 23 can be connected to the conduit body 1 through connector 24 and connecting assembly 4.

[0059] Regarding the positional distribution and connection relationship of the first microwave tube 21, the second microwave tube 22, and the third microwave tube 23, the first microwave tube 21 is located at the foremost end of the conduit body 1, and its radiation range is the first radiation zone 25. The second microwave tube 22 and the third microwave tube 23 are distributed at intervals, with the second microwave tube 22 located between the first microwave tube 21 and the third microwave tube 23. The three are connected by the connecting component 4, and there is a gap between them. The radiation range of the second microwave tube 22 is the second radiation zone 26, and the radiation range of the third microwave tube 23 is the third radiation zone 27.

[0060] To ensure the radiation effect of the first microwave tube 21, the second microwave tube 22, and the third microwave tube 23, and to achieve a stable ablation effect at the edge of the radiation area, the radiation edges of the first radiation area 25 and the second radiation area 26, and the second radiation area 26 and the third radiation area 27 overlap. This allows for a stable ablation effect even at the weaker microwave edges.

[0061] To facilitate the guidance of the ablation catheter through the vascular sheath into the vein, a microwave needle 12 is provided at the front end of the first microwave tube 21 using the connecting component 4. The ablation catheter can enter the vein through the vascular sheath under the action of the microwave needle 12.

[0062] The microwave needle 12 is a cone-shaped head. The microwave needle 12 is preferably made of PEEK material. A connector 24 protrudes perpendicularly to the end face of the microwave needle 12. The connector 24 can cooperate with the connecting component 4 for fixed connection.

[0063] The connecting component 4 includes a connecting bracket 41, which is a circular plastic tube made of PEEK material. The outer diameter of the connecting bracket 41 is the same as the outer diameter of the conduit body 1, and the inner diameter of the connecting bracket 41 is slightly smaller than the inner diameter of the conduit body 1. To facilitate connection, an annular groove is recessed perpendicular to the end face of one end of the connecting bracket 41, which is named the outer connecting groove 42. The inner diameter of the connecting groove 42 is the same as the inner diameter of the connector 24. The two can be inserted together, and to improve the sealing of the connection, glue is applied to the connection point. At the same time, a boss with the same diameter as the connector 24 protrudes from the end face of the other end of the connecting bracket 41. This end of the connecting bracket 41 can be inserted into the conduit body 1, and glue is applied to the connection point to improve the sealing of the connection.

[0064] Definition: In this embodiment, one end of the catheter body 1 on which the operating handle 5 is installed is the end point, and the other end is the front point.

[0065] like Figure 3 , 4 As shown in Figure 5, the temperature measuring component 3 includes a first temperature measuring coupler 31, a second temperature measuring coupler 32, a third temperature measuring coupler 33, a fourth temperature measuring coupler 34, and a fifth temperature measuring coupler 35.

[0066] The first temperature measuring coupler 31, the second temperature measuring coupler 32, the third temperature measuring coupler 33, the fourth temperature measuring coupler 34, and the fifth temperature measuring coupler 35 are all ring-shaped temperature measuring couplers. In order to facilitate the wiring of the semi-rigid coaxial cable 11, the inner diameter of the first temperature measuring coupler 31, the second temperature measuring coupler 32, the third temperature measuring coupler 33, the fourth temperature measuring coupler 34, and the fifth temperature measuring coupler 35 is larger than the outer diameter of the semi-rigid coaxial cable 11, and the semi-rigid coaxial cable 11 can pass through the inner diameter of the temperature measuring coupler. In order to facilitate the power supply of the temperature measuring coupler, the first temperature measuring coupler 31, the second temperature measuring coupler 32, the third temperature measuring coupler 33, the fourth temperature measuring coupler 34, and the fifth temperature measuring coupler 35 are respectively connected to the power interface 51 at the operating handle 5 through wires (the wires are not shown in the diagram).

[0067] To facilitate the installation of the thermocouple, a connecting tube 28 is fitted around the thermocouple. The connecting tube 28 is a plastic tube made of PEEK material. The outer and inner diameters of the connecting tube 28 are the same as the outer and inner diameters of the conduit body 1. The annular boss at one end of the connecting bracket 41 can be inserted into the connecting tube 28.

[0068] Regarding the functions of the first thermocouple 31, the second thermocouple 32, the third thermocouple 33, the fourth thermocouple 34, and the fifth thermocouple 35, the first thermocouple 31 is located at the overlap of the first radiation zone 25 and the second radiation zone 26, and the second thermocouple 32 is located at the overlap of the second radiation zone 26 and the third radiation zone 27. The function of these two is to monitor the temperature of the ablation area and prevent incomplete ablation in the overlapping area. The third thermocouple 33 is close to the third microwave tube 23 and is located inside the third radiation zone 27. The fifth thermocouple 35 is located outside the third radiation zone 27, and the fourth thermocouple 34 is located between the two. By observing the temperature changes and temperature rise curves of the third thermocouple 33, the fourth thermocouple 34, and the fifth thermocouple 35, the length of a single ablation can be determined. This effectively improves surgical efficiency and reduces complications caused by repeated local ablation while ensuring complete ablation.

[0069] In this embodiment, the connection and fixation of the first microwave tube 21, the second microwave tube 22, and the third microwave tube 23 to the connecting bracket 41 are all fixed with sealant. After fixing, there will be no leakage at the joint. The fixing of the connecting tube 28 to the connecting bracket 41 and the connecting bracket 41 to the first temperature measuring coupler 31, the second temperature measuring coupler 32, the third temperature measuring coupler 33, the fourth temperature measuring coupler 34, and the fifth temperature measuring coupler 35 are also fixed with sealant, and there will be no leakage at the joint after fixing.

[0070] In this embodiment, the assembly relationship between the radiation component 2 and the temperature measuring component 3 is as follows: During connection, each end of the first microwave tube 21 is fixed with a connecting bracket 41 using glue. Simultaneously, a microwave needle 12 is glued to the connecting bracket 41 at the front end. At the other end of the connecting bracket 41, a connecting tube 28 is glued to the connector 24. The first temperature measuring coupler 31 is fixed to the inner wall of this connecting tube 28 and placed centrally. A connecting bracket 41 is fixed to the other end of this connecting tube 28. A second microwave tube 22 is fixed to the other end of the connecting bracket 41, and a connecting bracket 41 is fixed to the other end of the second microwave tube 22. A connecting tube 28 is fixed at the other end. A second temperature measuring coupler 32 is fixed in the center on the inner side wall of the connecting tube 28. A connecting bracket 41 is fixed at the other end of the connecting tube 28. A third microwave tube 23 is fixed at the other end of the connecting bracket 41. A connecting bracket 41 is fixed at the other end of the third microwave tube 23. The other end of the connecting bracket 41 is inserted into the front port of the conduit body 1 and fixed with glue. A third temperature measuring coupler 33 is fixed with glue inside the conduit body 1 at the connecting bracket 41. At the same time, a fourth temperature measuring coupler 34 is fixed 1 cm away from the third temperature measuring coupler 33. A fifth temperature measuring coupler 35 is fixed 1 cm away from the fourth temperature measuring coupler 34.

[0071] To ensure the smoothness of the device as a whole and facilitate its entry into the vein through the vascular sheath, an outer sleeve 13 is fitted over the front end of the catheter body 1. The outer sleeve 13 is fixed and cannot be removed. The outer sleeve 13 is fitted over the radiation component 2 and the connecting component 4. The outer sleeve 13 is a circular tube, and in this embodiment, it is preferably made of polytetrafluoroethylene material. In order to prevent the outer sleeve 13 from affecting the microwave ablation of the microwave head, the outer sleeve 13 is made to give way at the first microwave tube 21, the second microwave tube 22 and the third microwave tube 23, that is, the first microwave tube 21, the second microwave tube 22 and the third microwave tube 23 are exposed on the outside.

[0072] The control unit includes a control board, whose main function is to receive signals and control the ablation power and ablation time. It can be used directly with existing devices. The power interface 51 on the operating handle 5 and the various thermocouples in the temperature measuring component 3 are connected to the control board. The control board is then connected to the computer. The ablation power and ablation time of the first microwave tube 21, the second microwave tube 22 and the third microwave tube 23 can be adjusted respectively through the operating keys on the computer. The control unit is a device used in conjunction with the ablation catheter. Unlike the ablation catheter, the control unit is not a disposable device and can be used continuously.

[0073] This invention also provides an ablation monitoring system for microwave ablation catheters for varicose veins, including a microwave ablation device as an energy source configured to provide microwave energy to the microwave ablation catheter; and a temperature monitoring device, which can be coupled into the microwave ablation device or a separate microprocessor, for receiving and storing temperature information from the temperature sensing components and displaying the temperature rise curve, such as... Figure 6 and 7 As shown, in addition to displaying the heating curve, it can also be used to display information known in the art such as power and time, and adjust the ablation power and ablation time according to the heating curve.

[0074] In this invention, the temperature monitoring device also stores temperature information and corresponding ablation information. Because the ablation catheter has multiple radiation zones, the overlapping of thermal fields causes a rapid temperature rise, resulting in a rapid increase in the ablation length and short diameter within a short period. To ensure ablation safety, ablation information, including ablation power, time, and corresponding ablation length and short diameter dimensions, can be stored in the microprocessor before ablation. Before ablation, the patient's information is input into the microprocessor, which can automatically recommend ablation length and short diameter dimensions based on the stored information. Then, based on the ablation length and short diameter dimensions, the ablation power and ablation time are recommended to prevent over-ablation and thermal damage.

[0075] like Figure 6 , 7 As shown in Figure 8, the method for measuring the single ablation length of varicose vein ablation catheters specifically includes the following steps:

[0076] Step 1, Catheter Placement: Under ultrasound guidance, the catheter body 1 is inserted through the vascular sheath into the great saphenous vein, and an anesthetic swelling solution is injected locally;

[0077] Step 2: Set ablation parameters: Determine the ablation power based on the ablation location, and use the control unit to set the ablation power and ablation duration;

[0078] Step 3: Temperature rise curve generation: The temperature measuring components respectively return the temperature values ​​of the five temperature measuring couplers, and generate temperature rise curves of the five temperature measuring couplers during the ablation process on the computer. The temperature monitored by the first temperature measuring coupler 31 is named T1, the temperature monitored by the second temperature measuring coupler 32 is named T2, the temperature monitored by the third temperature measuring coupler 33 is named T3, the temperature monitored by the fourth temperature measuring coupler 34 is named T4, and the temperature monitored by the fifth temperature measuring coupler 35 is named T5.

[0079] Step 4: Determine the single ablation length: Based on the temperature readings and temperature rise curves from the five thermocouples fed back by the temperature sensing components, calculate the single ablation length using the formula M=L1+L2+L3-LY+LX.

[0080] In the formula:

[0081] M represents the total length of a single ablation session;

[0082] L1 is the length of the first radiation zone 25;

[0083] L2 is the length of the second radiation zone 26;

[0084] L3 is the length of the third radiation zone 27;

[0085] LX is the distance 27 from the ablation end to the third radiation zone;

[0086] LY is the total overlap length of the radiation region;

[0087] Step 5: Once a single ablation is complete, withdraw the needle according to the length of the ablation, and continue ablation until it is completely completed.

[0088] In step two, the preferred ablation power is 60W, the ablation time for the coarser starting area is 11s, and the ablation time for the slightly thinner main trunk is 6s.

[0089] In this embodiment, regarding the calculation of the single ablation length in step four, it is preferred that the ablation length of a single microwave tube is 2.5cm, i.e., L1, L2, and L3 are all 2.5cm. The overlap area between two adjacent microwave tubes is 0.5cm. Therefore, the total length of the three ablation areas is 2.5 + 2.5 + 2.5 - 0.5 - 0.5 = 6.5cm. The values ​​of L1, L2, L3, and LY can be preset in the control unit. The total overlap length of the radiation area is 0.5 + 0.5 = 1cm. LX is the distance from the ablation end to the third radiation area 27 automatically calculated by the control unit. The calculation method is based on the temperature rise curve, according to the total temperature difference between the third temperature measuring coupler 33 and the fifth temperature measuring coupler 35 and the distance between the third temperature measuring coupler 33 and the fifth temperature measuring coupler 35, calculated according to the curvature of the temperature rise curve, thus obtaining an accurate value.

[0090] In this embodiment, it is preferred that the distance between the fourth temperature measuring coupler 34 and the third temperature measuring coupler 33 is 1cm, and the distance between the fifth temperature measuring coupler 35 and the fourth temperature measuring coupler 34 is 1cm.

[0091] The calculation process for the single ablation length in this embodiment is as follows: Taking a 60W ablation power and an ablation time of 11s as an example, if the LX calculated by the control unit is 1.5cm, substitute it into the formula M=L1+L2+L3-LY+LX for calculation. The single ablation length M is 2.5+2.5+2.5-1+1.5=8cm. Therefore, the single ablation length is 8cm. After the single ablation is completed, when continuing ablation, the tube is withdrawn by 8cm according to the length of the single ablation for subsequent ablation.

[0092] The above embodiments are merely illustrative of the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solutions based on the technical concept proposed in this invention shall fall within the scope of protection of this invention.

Claims

1. A varicose vein ablation catheter, comprising a catheter body (1), wherein an operating handle (5) is provided at one end of the catheter body (1), characterized in that: It also includes a radiation component (2), a temperature measuring component (3), a connecting component (4), and a control unit. The radiation component (2) is installed on the conduit body (1) through the connecting component (4). The radiation component (2) is connected to a semi-rigid coaxial cable (11) inside the conduit body (1). The temperature measuring component (3) is installed inside the conduit body (1) and close to the radiation component (2). The temperature measuring component (3) measures the temperature inside and outside the radiation area of ​​the radiation component (2). The control unit connected to the radiation component (2) and the temperature measuring component (3) is connected to the computer. The control unit controls the power of the radiation component (2) and generates a temperature curve on the computer based on the temperature measured by the temperature measuring component (3) to determine the single ablation length. The temperature measuring component (3) includes a temperature measuring coupler inside the radiation zone and a temperature measuring coupler outside the radiation zone. The temperature measuring coupler inside the radiation zone is set in the radiation zone at the front of the conduit body (1), and the temperature measuring coupler outside the radiation zone is set in the radiation zone outside the rear end of the conduit body (1), outside the microwave head radiation area at the rear end. The thermocouples in the radiation zone include a first thermocouple (31), a second thermocouple (32), and a third thermocouple (33). The first thermocouple (31) is located inside the conduit body (1) at the point where it overlaps with the radiation edges of the first radiation zone (25) and the second radiation zone (26). The second thermocouple (32) is located inside the conduit body (1) at the point where it overlaps with the radiation edges of the second radiation zone (26) and the third radiation zone (27). The third thermocouple (33) is located inside the conduit body (1) near the middle of the third radiation zone (27). The thermocouples outside the radiation zone include a fourth thermocouple (34) and a fifth thermocouple (35). The fourth thermocouple (34) is located at the edge of the third radiation zone (27) on the main body of the conduit (1), and the fifth thermocouple (35) is located outside the third radiation zone (27). The distance between the fifth thermocouple (35) and the fourth thermocouple (34) is the same as the distance between the fourth thermocouple (34) and the third thermocouple (33).

2. The varicose vein ablation catheter according to claim 1, characterized in that: The radiation assembly (2) includes a microwave head, which forms a radiation area on the conduit body (1). The microwave head includes a first microwave tube (21), a second microwave tube (22), and a third microwave tube (23). The first microwave tube (21) is disposed at the end of the conduit body (1) to form a first radiation area (25). The second microwave tube (22) is connected to the first microwave tube (21) through a connecting assembly (4). The two are spaced apart to form a second radiation area (26). The third microwave tube (23) is connected to the second microwave tube (22) through a connecting assembly (4). The two are spaced apart to form a third radiation area (27). The first radiation zone (25), the second radiation zone (26) and the third radiation zone (27) are distributed at intervals, and the radiation ranges of the three overlap at the edges.

3. The varicose vein ablation catheter according to claim 1, characterized in that: The connection component (4) includes a connection slot (41), one end of which is provided with a connection groove (42) and the other end is provided with a connector (24). The connection groove (42) can be fixed in conjunction with the end of the microwave head, and the connector (24) can be inserted into the conduit body (1).

4. The varicose vein ablation catheter according to claim 1, characterized in that: An outer sleeve (13) is fitted onto the front end of the radiation assembly (2) installed on the catheter body (1). The outer sleeve (13) is disconnected near the microwave head on the radiation assembly (2), and the microwave head for microwave ablation is exposed to the outside.

5. The ablation monitoring system for a varicose vein ablation catheter according to any one of claims 1-4, characterized in that: It includes a microwave ablation device and a temperature monitoring device. The microwave ablation device is configured to provide microwave energy to the microwave ablation catheter, and the temperature monitoring device displays the temperature rise curve and adjusts the ablation power and ablation time according to the temperature rise curve.

6. The ablation monitoring system for a varicose vein ablation catheter according to claim 5, characterized in that: The temperature monitoring device also stores temperature information and corresponding ablation information, including ablation power, time, and corresponding ablation major and minor diameters.

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