Radiofrequency ablation catheter, pulmonary radiofrequency ablation system, and corresponding control method

Abstract

The present application relates to a radiofrequency ablation catheter, a pulmonary radiofrequency ablation system, and a corresponding control method, wherein the radiofrequency ablation catheter includes an electrode, the distal end of the electrode is a sharp tip and has a heat exchange medium flow channel, the electrode is provided with an equalizing device, the equalizing device is provided with an infiltration hole connected to the heat exchange medium flow channel, and the heat exchange medium output by the heat exchange medium flow channel is distributed and flows out through the equalizing device. The present application utilizes the electrode to infuse physiological saline into the ablated tissue, thereby improving the electrical conductivity and thermal conductivity of the ablated tissue, maintaining impedance balance, keeping the impedance in a relatively stable state, and enabling continuous output of radiofrequency energy.

Description

[0001] This application is a divisional application of the patent application with application number 201910292690.5;

[0002] The information of the patent application with application number 201910292690.5 is as follows:

[0003] Invention name: Radiofrequency ablation catheter, pulmonary radiofrequency ablation system, and corresponding control method, control device and computer-readable storage medium;

[0004] Application date: April 12, 2019. Technical Field

[0005] The present application relates to the field of minimally invasive ablation treatment of tumors, and in particular to a radiofrequency ablation catheter, a lung radiofrequency ablation system, and a corresponding control method. Background Art

[0006] Lung cancer is one of the most common malignant tumors. In clinical treatment, surgical resection is still the first choice for treating early lung cancer. However, for lung cancer patients who are older, weaker, have poor cardiopulmonary function, or have complications, they are not suitable for or cannot tolerate conventional surgical resection. Therefore, many local treatment methods such as minimally invasive tumor ablation have emerged. Minimally invasive ablation of lung tumors includes radiofrequency ablation (RFA), cryoablation, microwave ablation, etc. Among them, only radiofrequency ablation is included in the clinical guidelines for non-small cell lung cancer of the National Comprehensive Cancer Network of the United States.

[0007] The principle of radiofrequency ablation is to use an alternating high-frequency current with a frequency of less than 30MHz (usually 460-480kHz) to cause the ions in the tumor tissue to oscillate at high speed, rub against each other, and convert the radiofrequency energy into heat energy, causing coagulative necrosis of tumor cells. In radiofrequency ablation treatment, the device used is a radiofrequency ablation catheter, and the electrode at its distal end can transmit radiofrequency energy to the cell tissue around the puncture site after percutaneous puncture. During radiofrequency ablation treatment, the radiofrequency ablation catheter is the electrode that outputs radiofrequency energy. It is connected to the radiofrequency generator and, under the guidance of B-ultrasound or CT, is percutaneously punctured and punctured into the target tumor through the puncture point. The neutral electrode plate is also connected to the radiofrequency generator and is attached to the appropriate part of the patient's body. When the foot switch on the radiofrequency generator is stepped on, the radiofrequency ablation catheter is connected to the neutral electrode plate, and the high-frequency current acts on the human tissue between the two, causing the tumor cells contacted by the electrode at the distal end of the radiofrequency ablation catheter to coagulate, degenerate, and necrotize.

[0008] The inventors found that when the existing radiofrequency ablation catheter for the lungs is working, the temperature of the electrode part rises too quickly, and the tissue near the electrode dries and carbonizes to form a "scab", which causes the ablation to stop and the ablation to be incomplete. Moreover, the "scab" tissue adheres to the electrode, and the surrounding organs will be damaged when the instrument is pulled out.

[0009] The heads of most existing radiofrequency ablation catheters used for lungs cannot be bent, so that the front-end electrodes of the radiofrequency ablation catheters cannot easily reach the target position on the side.

[0010] Existing radiofrequency ablation catheters cannot effectively control the ablation range and cannot timely determine whether the ablation range is appropriate. If the ablation range is small, the ablation is not thorough and there is a risk of recurrence; if the ablation range is large, it may accidentally injure surrounding normal tissues and organs.

[0011] The existing radiofrequency ablation operation cannot effectively determine the exact position of the front electrode of the radiofrequency ablation catheter even under the guidance of B-ultrasound or CT. CT images are a limited number of cross-sectional images obtained by X-ray scanning. At certain angles, it looks like the front electrode is placed at the target site, but the actual position may be wrong, and it is just overlapping in the projection direction. Therefore, the position of the front electrode is difficult to determine and the positioning accuracy is insufficient. Summary of the invention

[0012] In order to solve at least some of the problems raised in the background technology, the purpose of the present application is to provide a radiofrequency ablation catheter, whose electrode can infuse a heat exchange medium into the ablated tissue and form a heat exchange medium protective film on the periphery of the electrode, thereby improving the electrical conductivity and thermal conductivity of the ablated tissue, maintaining impedance balance, keeping the impedance in a relatively stable state, and enabling continuous output of radiofrequency energy.

[0013] The present application discloses a radiofrequency ablation catheter, comprising an electrode, wherein the distal end of the electrode is a pointed tip and has a heat exchange medium flow channel, the electrode is provided with an equalizing device, the equalizing device is provided with an infiltration hole connected to the heat exchange medium flow channel, and the heat exchange medium output from the heat exchange medium flow channel is distributed and flows out via the equalizing device.

[0014] Several optional methods are also provided below, but they are not intended to be additional limitations on the above-mentioned overall solution, but are merely further supplements or preferences. Under the premise that there are no technical or logical contradictions, each optional method can be combined with the above-mentioned overall solution separately, and multiple optional methods can also be combined.

[0015] Optionally, the equalizing device and the electrode are an integrated structure, and the wetting hole is opened on the outer wall of the electrode.

[0016] Optionally, the distal end of the electrode is a cone or a pyramid.

[0017] Optionally, the distal end of the electrode is formed by chamfering at least one of a spherical cap, a truncated cone, and a prism to form the tip.

[0018] Optionally, the distal end of the electrode is a cylinder, and the tip is formed by beveling three faces of the cylinder.

[0019] Optionally, the heat exchange medium flow channel includes a main flow channel and a plurality of branch flow channels connected to the main flow channel, and a terminal end of each branch flow channel extends to an outer surface of the electrode.

[0020] Optionally, there is one main channel, which is set at the axial position of the electrode and extends along the axial direction of the electrode, and multiple branch channels are connected at different positions of the main channel; the branch channels are arranged in at least one group along the extension direction of the main channel, and there are at least two branch channels in the same group, which are radially distributed on the periphery of the main channel, and the branch channels in the same group are evenly arranged in the circumferential direction; the number of branch channels in adjacent groups is the same or different, and the circumferential positions are aligned or staggered.

[0021] Optionally, the wetting holes are arranged in a certain manner or path regularly on the periphery of the electrode;

[0022] The infiltration holes are distributed at the same density at different locations on the periphery of the electrode, or are arranged accordingly according to the balance of heat exchange medium flow.

[0023] The present application also discloses an ablation system, comprising:

[0024] The radiofrequency ablation catheter in the above technical solution;

[0025] A heat exchange medium delivery device for providing heat exchange medium to the peripheral area of ​​the electrode of the radiofrequency ablation catheter;

[0026] The control module of the heat exchange medium conveying device is driven accordingly according to the impedance information or temperature information of the loop where the electrode in the radio frequency ablation catheter is located.

[0027] The present application also discloses a control method for radiofrequency ablation, which is applied to the ablation system in the above technical solution and is characterized by comprising:

[0028] Controlling the radio frequency signal generator to generate a radio frequency signal and transmitting the radio frequency signal to the radio frequency ablation catheter;

[0029] Obtaining impedance information and temperature information of the contact position between the radiofrequency ablation catheter and the ablation tissue;

[0030] Based on the impedance information, a microinfusion pump is controlled to infuse a heat exchange medium into the ablation catheter. The impedance information is compared with a threshold value through a control module, and the impedance information is made close to a steady-state impedance by adjusting the heat exchange medium flow rate.

[0031] This application detects the impedance change around the ablated tissue. When a sharp increase in impedance is detected, it means that the ablated tissue near the electrode is drying and carbonizing, and scabs will form. At this time, physiological saline is controlled to be perfused into the ablated tissue to reduce the temperature of the tissue and increase the humidity of the tissue, fundamentally avoiding the formation of scabs due to drying and heating of the tissue; at the same time, physiological saline can improve the conductivity and thermal conductivity of the tissue, maintain impedance balance, and keep the impedance in a relatively stable state. The combination of the two ensures that the impedance is stable within a certain range during the entire ablation process, so that the radio frequency energy can be continuously output, thereby forming a sufficiently large ablation range, producing a larger and more effective coagulation necrosis focus, and avoiding the "scab" of the tissue, and also avoiding the problem of the "scab" tissue adhering to the electrode, which will damage the surrounding organs when the instrument is pulled out.

[0032] Other beneficial effects of the present application will be further described in the specific implementation manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The figure is the overall structure diagram of the radiofrequency ablation catheter;

[0034] Figure 2 is a cross-sectional view of the inserted portion;

[0035] Figure 3 is another cross-sectional view of the insert portion;

[0036] Figure 4 is a cross-sectional view of the handle portion;

[0037] Figure 5 is another cross-sectional view of the handle portion;

[0038] Figure 6a is an external structural diagram of the first elbow assembly;

[0039] Figure 6b for Figure 6a Middle AA section;

[0040] Figure 7a is an external structural diagram of the second elbow assembly;

[0041] Figure 7b for Figure 7a Middle AA section;

[0042] Figure 8 It is a structural diagram of the electrode (the infiltration cover and the electrode are an integrated structure);

[0043] Fig. 9 It is a structural diagram of the electrode (the infiltration cover and the electrode are separate structures);

[0044] Fig.10a for Fig. 9 A cross-sectional view of

[0045] Fig.10b is a partial cross-sectional view of the electrode;

[0046] Fig.10c is a partial cross-sectional view of the electrode;

[0047] Fig.10d is a partial cross-sectional view of the electrode;

[0048] Fig.11 The figure is the overall structure diagram of the radiofrequency ablation catheter;

[0049] Fig.12 for Fig.11 A partial enlarged view of the

[0050] Fig.13 for Fig.11 Section view in ;

[0051] Fig.14 It is a structural diagram of the electrode (the infiltration cover and the electrode are an integrated structure);

[0052] Fig.15 for Fig.14 Another angle view of the middle electrode;

[0053] Fig.16 for Fig.15 Middle AA section;

[0054] Fig.17 for Fig.14 Another angle view of the middle electrode;

[0055] Fig.18a Schematic diagram of temperature change around the electrode during ablation;

[0056] Fig.18b This is a schematic diagram of the installation location of the temperature detection device in the radiofrequency ablation catheter;

[0057] Fig.18c for Fig.18b The schematic diagram after omitting the thermal conductive ring;

[0058] Fig.18d It is a cross-sectional view of the heat conducting ring;

[0059] Fig.19 This is a schematic diagram of the temperature distribution of the lesion during radiofrequency ablation;

[0060] Fig. 20 A flowchart of a control method for radiofrequency ablation of the lung;

[0061] Fig.21 A schematic diagram of a lung radiofrequency ablation system;

[0062] Fig. 22 Schematic diagram of another lung radiofrequency ablation system.

[0063] Description of reference numerals:

[0064] 1. Electrode; 101. Brine connecting pipe; 102. First mounting hole; 103. Second mounting hole; 104. Third mounting hole; 105. Fourth mounting hole; 106. Brine hole; 107. Settling area; 111. Connecting pipe; 112. Mounting hole; 113. Mounting hole; 114. Tip; 115. Main channel; 116. Branch channel; 117. Branch channel; 118. Branch channel; 119. Infiltration hole; 2 , sheath; 3, protective tube; 4, first bending assembly; 400, finger ring; 401, sliding chamber; 402, connector; 403, limit screw; 5, second bending assembly; 500, wire passage cavity; 501, sliding tube body; 502, slide groove; 503, bolt hole; 504, groove; 6, saline connector; 7, ablation device connector; 8, electrode ring; 9, thermistor; 90, thermistor wire; 91, temperature control sleeve; 10. Pull wire; 11. Spring hose; 12. Brine pipe; 13. Pull wire fixing bolt; 14. End cover; 15. O-ring; 16. Wire; 17. Pressure sensor; 18. Forked rivet tube; 19. Temperature sensor; 20. Wetting cover; 200. Wetting hole; 201. Wetting hole; 202. Wetting hole; 21. Metal pipe; 22. Temperature sensor; 23. Heat exchange medium delivery pipe; 24. Electrode wire; 25. Y type handle; 26, handle end cover; 27, connector; 28, Luer connector; 29, temperature sensor; 211, radio frequency ablation catheter; 212, embedding groove; 213, first through hole; 214, thermal conductive ring; 215, sink groove; 216, second through hole; 100, radio frequency signal generator; 110, ablation catheter; 120, sensor module; 130, micro-infusion pump; 140, control module; 150, alarm module. DETAILED DESCRIPTION

[0065] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0066] In order to better describe and illustrate the embodiments of the present application, reference may be made to one or more drawings, but the additional details or examples used to describe the drawings should not be considered as limiting the scope of the invention of the present application, any of the currently described embodiments or preferred methods.

[0067] It should be noted that when a component is referred to as being "connected" to another component, it may be directly connected to the other component or there may be a central component. When a component is referred to as being "disposed on" another component, it may be directly disposed on the other component or there may be a central component at the same time.

[0068] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which the present application belongs. The terms used herein in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0069] like Figures 1 to 18d As shown in FIG, the radiofrequency ablation catheter as a whole comprises an insertion portion and a handle portion, wherein an electrode 1 is provided at the distal end of the insertion portion.

[0070] A radiofrequency ablation catheter in one embodiment of the present application includes an electrode 1, wherein the electrode 1 has a heat exchange medium flow channel, an equalizing device is provided on the electrode 1, and an infiltration hole connected to the heat exchange medium flow channel is provided on the equalizing device. The heat exchange medium output from the heat exchange medium flow channel is distributed and flows out through the equalizing device.

[0071] In this embodiment, the heat exchange medium that can be output to the heat exchange medium flow channel is further distributed by the balancing device to form a heat exchange medium protective film between the electrode 1 and the lesion tissue. Its design concept and principle are different from ordinary cooling. The distribution method can use multiple holes, slits, etc. to at least avoid outputting the heat exchange medium in the same part. Through distribution, a relatively uniform heat exchange medium protective film can be formed on the outer surface of the electrode 1, which can reduce the temperature of the tissue, increase the humidity of the tissue, and fundamentally avoid the tissue from forming scabs due to drying and heating; at the same time, the heat exchange medium can improve the electrical conductivity and thermal conductivity of the tissue, maintain impedance balance, and keep the ablation stable.

[0072] In one embodiment, the equalizing device and the electrode are separate structures, and the equalizing device is fixedly or movably mounted on the electrode; or the equalizing device and the electrode are integrated structures.

[0073] When the equalizing device and the electrode are an integrated structure, that is, the equalizing device is a part of the electrode, the infiltration hole is opened on the outer wall of the electrode, and the equalizing device at least surrounds a part of the heat exchange medium flow channel, and the infiltration hole on the equalizing device corresponds to the area, that is, it is connected. The equalizing device can be a section on the axial direction of the electrode, and the section is preferably continuously distributed in the circumferential direction, that is, the infiltration holes are multiple and distributed along the circumferential direction, so that the heat exchange medium distribution effect is better, and the heat exchange medium protective film formed is more uniform, avoiding the formation of the protective film only in the circumferential part.

[0074] In one embodiment, there are multiple wetting holes for forming a uniform heat exchange medium protective film outside the electrode.

[0075] There are multiple infiltration holes, which is more conducive to the balanced distribution of the heat exchange medium. The infiltration holes can be arranged in a certain way or path rule on the periphery of the equalizing device, or they can be randomly distributed. The heat exchange medium output from the heat exchange medium flow channel penetrates through each infiltration hole and flows out to the outside of the equalizing device, and then surrounds the electrode to form a uniform heat exchange medium protective film. The specific distribution of the infiltration holes is further provided in a preferred embodiment later.

[0076] The pore size of the wetting hole is 0.1-0.3 mm. A suitable pore size is more conducive to the distribution and formation of the heat exchange medium protective film. When the shape of the wetting hole is non-circular, the area of ​​the circular hole can be referred to for conversion to ensure the heat exchange medium flow rate at the wetting hole.

[0077] In one embodiment, the infiltration hole is slit-shaped. Compared with the general shape, the slit has a distinct length direction, for example, the length is more than 5 times the width, and the width of the slit can generally be set to about 0.1 mm. The length direction of the slit extends along the electrode axial direction or circumferential direction, or forms a certain angle with the axial direction.

[0078] In a radiofrequency ablation catheter of one embodiment of the present application, the equalizing device and the electrode are separated structures, the outer wall of the electrode 1 is provided with an outflow hole connected to the heat exchange medium flow channel, the equalizing device is an infiltration cover 20 installed on the electrode 1 and located outside the outflow hole, the infiltration hole is provided on the infiltration cover 20, and the heat exchange medium output from the outflow hole is distributed and flows out through the infiltration cover 20.

[0079] In the present application, the distal end is understood as the end close to the lesion, the proximal end is understood as the end away from the lesion, that is, close to the handle part, and the axial direction is understood as the direction in which the sheath extends. Although the sheath can be partially bent, it can be understood in combination with the state before bending.

[0080] As for the electrode itself, except for the most distal part, the rest of the electrode generally adopts a rotating body structure, such as a cylindrical shape, and therefore also has an axial and radial direction in space, and the axial direction of the electrode is consistent with the extension direction of the sheath tube.

[0081] In a preferred embodiment, all the outflow holes are covered by the wetting cover 20 , but in some embodiments, some of the outflow holes may be exposed to the wetting cover 20 , that is, not covered by the wetting cover 20 .

[0082] In one embodiment, the distal end of the electrode extends in a constant diameter or converges in shape, wherein the convergence in shape is gradual or step-wise.

[0083] The convergence of the shape facilitates the implementation of puncture and advancement in the body. During convergence, the diameter or outer contour gradually decreases toward the distal end, and the decreasing trend can be fixed (gradual convergence) or variable (step-like convergence).

[0084] In one embodiment, the distal end of the electrode is a cylinder, spherical cap, truncated cone, truncated pyramid, cone, pyramid, or a shape obtained by chamfering the above shapes (referring to a cylinder, spherical cap, truncated cone, truncated pyramid, cone or pyramid) with at least one face.

[0085] By using one or more surfaces for beveling, the shape of the distal end of the electrode can be more varied. Beveling means that the beveled surface is not parallel or perpendicular to the electrode axis. Parallel surfaces cannot be beveled, while perpendicular surfaces mean that the distal end surface of the electrode is a plane, such as a cylindrical or truncated cone structure.

[0086] For example Fig. 9 The distal end of the middle electrode 1 is in the shape of a truncated cone.

[0087] In one embodiment, the equalizing device and the electrode are an integrated structure, the infiltration hole is opened on the outer wall of the electrode, and the distal end of the electrode is a pointed tip. Fig.14 The distal end of the middle electrode 1 is a tip 114, which can be specifically considered to be formed by obliquely cutting three facing cylinders. The tip 114 facilitates puncture and movement in the body.

[0088] Although some preferred embodiments are provided above, the shape of the distal end of the electrode itself can also be implemented using existing technologies.

[0089] In this embodiment, the heat exchange medium flow channel can be connected to the external heat exchange medium delivery device through a connecting pipe, and necessary pumps, valves or metering devices can be installed on the pipeline as needed. Fig.16 The proximal end of the middle electrode 1 is provided with a connecting pipe 111 , and inside the electrode 1 is a main flow channel 115 that is butt-connected to the connecting pipe 111 for transmitting heat exchange medium.

[0090] As for the heat exchange medium itself, existing technology can be used, mainly for cooling ablation and surrounding areas, but in some scenarios, it may also be used for heating. The relationship between the heat exchange medium temperature and body temperature can be adjusted as needed.

[0091] Since the heat exchange medium needs to be input into the body, it should be a substance that is medically acceptable to the human body. In terms of physical form, it can be gas, liquid or solid powder with a certain fluidity, or a combination of multiple physical forms. The heat exchange medium can be a pure substance or a mixture, and can be combined with medication.

[0092] In one embodiment, the heat exchange medium flow channel is a cavity located inside the electrode 1, and the heat exchange medium flows out through the openings in the cavity wall.

[0093] The shape of the cavity space can be cylindrical, spherical, spherical cap or a combination of the above shapes, etc. The local periphery of the cavity is close to the surface of the electrode, that is, the cavity wall in this part is thinner, which is convenient for opening holes. The position of the cavity in the electrode is adapted to the distribution area of ​​the openings. The cavity space can be used to transport heat exchange medium on the one hand, and the heat exchange medium can also be pre-distributed or mixed to ensure that the heat exchange medium output through different openings remains consistent in temperature and concentration. The effect is more prominent when the heat exchange medium is combined with the application of pesticides.

[0094] When the equalizing device and the electrode are an integrated structure, the opening is the infiltration hole. When the equalizing device and the electrode are separate structures, the opening can be regarded as an outflow hole opened on the outer wall of the electrode.

[0095] In one embodiment, the heat exchange medium flow channel includes a main flow channel and a plurality of branch flow channels connected to the main flow channel, and a terminal end of each branch flow channel extends to the outer surface of the electrode 1 .

[0096] There can be one main channel or multiple channels arranged side by side. Preferably, one channel is arranged at the axial position of the electrode and extends along the axial direction of the electrode. The branch channels are connected at the same position or different positions of the main channel.

[0097] For example Fig.10a The middle part is a main flow channel extending along the electrode axis, and a plurality of branch flow channels are connected at the same position of the main flow channel.

[0098] Fig.16 In the figure, there is a main flow channel 115 extending along the electrode axis, and a plurality of branch flow channels are connected at different positions of the main flow channel 115 .

[0099] When the equalizing device and the electrode are an integrated structure, the end of each branch flow channel extends to the wetting hole on the outer surface of the electrode 1. When the equalizing device and the electrode are separate structures, the end of each branch flow channel extends to the outflow hole on the outer surface of the electrode 1.

[0100] In one of the embodiments, the branch flow channels are arranged in at least one group along the extension direction of the main flow channel, and the same group of branch flow channels includes at least two branch flow channels, which are radially distributed on the periphery of the main flow channel.

[0101] For ease of processing, the extension angle of the branch flow channel is preferably the radial direction of the electrode. Of course, it can also be arranged inclined relative to the radial direction. The inclination angles of each branch flow channel can be the same or different. When considering the axial position of each branch flow channel, the connection position with the main flow channel is used as a reference.

[0102] For example Fig.10a The middle branch flow channels are arranged in a group along the extension direction of the main flow channel, and Fig.16The middle branch channels are arranged in three groups along the extension direction of the main channel, and the figure shows branch channels 116, 117, and 118 connected at different positions (axial positions) of the main channel 115. The branch channels belonging to the same group are distributed radially.

[0103] In one embodiment, the branch flow channels in the same group are evenly distributed in the circumferential direction.

[0104] When distributed radially, the circumferentially uniform arrangement can be used to obtain a relatively uniform outflow.

[0105] In one embodiment, the numbers of adjacent groups of branch flow channels are the same or different, and the branch flow channels are aligned or staggered in the circumferential direction.

[0106] For example Fig.16 The number of adjacent groups of branch channels is the same and their circumferential positions are aligned, that is, branch channels 116, branch channels 117, and branch channels 118 in the figure are circumferentially aligned. Of course, in other embodiments, branch channels 116, branch channels 117, and branch channels 118 can also be staggered in the circumferential direction.

[0107] In one embodiment, a plurality of branch flow channels are sequentially arranged along the extension direction of the main flow channel and are spirally distributed around the periphery of the main flow channel. Physiological saline can be used as a relatively common heat exchange medium. For ease of description and understanding, some embodiments below take physiological saline as an example, and the corresponding outflow holes can also be called saline holes, and the heat exchange medium flow channels can also be called saline flow channels, and so on. However, as far as the "holes", "tubes", etc. are concerned, their structural characteristics are not strictly limited by the type of heat exchange medium unless otherwise specified.

[0108] If the heat exchange medium is physiological saline, then in one embodiment, the radiofrequency ablation catheter includes an electrode 1 electrically connected to the ablation device, one end of the electrode 1 has a saline connection tube 101 connected to the saline tube 12 to introduce physiological saline into the electrode 1, and a saline hole 106 connected to the inside of the saline connection tube 101 is formed on the electrode 1. The electrode 1 is further covered with an infiltration cover 20, and a plurality of infiltration holes 200 are evenly arranged on the infiltration cover 20. The physiological saline flowing out of the saline hole 106 can flow out from the infiltration hole 200. Figures 1 to 10c As shown in , a radiofrequency ablation catheter of one embodiment includes an insertion portion and a handle portion as a whole.

[0109] The insertion part includes: an electrode 1, a sheath tube 2 connected to the electrode 1, and parts located inside the electrode 1 and the sheath tube 2.

[0110] The handle part includes: a saline connector 6 and an ablator connector 7. The handle part is used to connect the insertion part to the saline storage position connected to the saline connector 6 and the ablator.

[0111] The wire 16 passes through the sheath tube 2 to connect the electrode 1 to the ablator connector 7, which is used to connect the electrode 1 to the ablator. The ablator is also connected to a neutral electrode plate. Before the ablation treatment begins, the neutral electrode plate is attached to a suitable part of the human body to form a loop between the electrode 1, the ablator, the neutral electrode plate and the patient, thereby ablating the ablation tissue contacted by the electrode 1. During use, the electrode 1 of the radiofrequency ablation catheter, under the guidance of bronchial navigation, passes through the forceps channel of the bronchoscope and enters the lung parenchyma through the hole pre-punctured in the bronchial wall near the lesion for radiofrequency ablation.

[0112] When the wetting cover 20 is used, the equalizing device and the electrode 1 can be regarded as separate structures, and the wetting hole 200 is also the wetting cover hole.

[0113] Of course, the equalizing device can also be an integrated structure with the electrode 1, for example Figure 2 , Figure 3 and Figure 8 As shown in FIG, one end of the electrode 1 is connected and fixed to the sheath 2, and the other end is directly embedded in the ablation tissue. The end of the electrode 1 fixed to the sheath 2 has a saline connection tube 101 extending into the inner body of the sheath 2. The saline connection tube 101 is connected to the saline connector 6 through the saline tube 12 to input physiological saline into the electrode 1. Figure 8 As shown in , the electrode 1 is provided with a plurality of saline holes 106. The saline flowing into the saline connecting tube 101 can enter the saline holes 106 through the holes inside the electrode 1 after entering the electrode 1 and flow out, so as to form an infiltration effect on the surface of the electrode 1. A saline film is formed on the surface of the electrode 1. During the ablation process, the saline fills between the electrode 1 and the ablated tissue, so as to prevent the "scab" from "vacuum wrapping" the electrode and causing a sudden increase in impedance.

[0114] Figure 2 , Figure 3 and Figure 8 The saline hole 106 in the electrode 1 can be regarded as an infiltration hole, and the part of the electrode 1 with the saline hole 106 can be regarded as an equalizing device.

[0115] In the case of an integrated structure, in order to ensure the wetting effect, there are multiple wetting holes, preferably multiple groups distributed in the axial direction of the electrode, such as 2 to 4 groups, and multiple wetting holes in each group are distributed along the circumference of the electrode, such as 2 to 8, preferably 4 to 6.

[0116] like Figures 11 to 17 As shown in , a radiofrequency ablation catheter of one embodiment comprises an insertion portion and a handle portion as a whole.

[0117] The insertion part includes: an electrode 1, a metal tube 21 connected to the electrode 1, and parts located inside the electrode 1 and the metal tube 21. In addition, a temperature sensor 29 is also arranged near the electrode 1.

[0118] The distal end of the electrode 1 converges to form a spike. The metal tube 21 is similar to the sheath 2 in structure and position, but the metal tube 21 has a certain strength and can also serve as a puncture needle together with the electrode 1. For example, it can directly puncture into the lungs through the outer wall of the chest cavity to perform ablation.

[0119] In this embodiment, the equalizing device and the electrode 1 are an integrated structure, and the electrode 1 has a heat exchange medium flow channel inside, such as the main channel 115, and branch channels 116, branch channels 117, and branch channels 118. The branch channels are connected to different positions of the main channel 115.

[0120] Each branch flow channel 116 extends to the outer surface of the electrode 1 to form an infiltration hole 109 . The section of the electrode 1 with the heat exchange medium flow channel and the infiltration hole 109 can be regarded as a balancing device with an integrated structure with the electrode 1 .

[0121] The electrode 1 is provided with mounting holes 112 and 113 for accommodating the temperature sensor 22 and the electrode wire 24 respectively. A connecting pipe 111 is provided at the proximal end of the electrode 1 to communicate with the heat exchange medium flow channel inside the electrode 1 , and the heat exchange medium delivery pipe 23 is connected to the connecting pipe 111 .

[0122] The handle portion mainly includes a Y-shaped handle 25 , a handle end cover 26 , and a Luer connector 28 .

[0123] The circuit part extends out of the Y-shaped handle 25 and enters the connector 27. The connector 27 can be connected to the external circuit through a commonly used interface form for plugging and unplugging. The heat exchange medium delivery pipe 23 can be connected to the heat exchange medium delivery device via the Luer connector 28 to supply the heat exchange medium to the electrode 1.

[0124] According to the length of the path of the electrode 1 in the body, a component with corresponding performance can be connected at the proximal end of the electrode 1. For example, if the path in the body is long and needs to be turned, a sheath tube 2 can be used. The sheath tube 2 has good flexibility and radial support ability and can adapt to larger bends. In addition, the bending degree and the posture of the electrode 1 can be adjusted in combination with the pull wire 10. For another example, if the path in the body is short or puncture is required, a metal tube 21 with a certain rigidity is used.

[0125] The electrode 1 and the sheath tube 2 or the metal tube 21 can be fixedly connected by existing means, such as welding, bonding, riveting or using an intermediate connector. The connection parts can be axially butted or partially nested with each other. When nested with each other, the outer wall is preferably flat and smooth to avoid sharp edges.

[0126] Combination Figure 9 to Figure 10dAs shown, in order to further optimize the infiltration effect of the electrode 1 during the ablation process, in some embodiments, the equalizing device adopts a structure separate from the electrode 1, for example, the electrode 1 is also provided with an infiltration cover 20 as an equalizing device. A certain gap is left between the inner peripheral wall of the infiltration cover 20 and the outer peripheral wall of the electrode 1.

[0127] There are a number of small infiltration holes 200 evenly distributed on the infiltration cover 20. The physiological saline that enters the internal channel of the electrode 1 from the saline connecting tube 101 flows into the gap between the electrode 1 and the infiltration cover 20 from the saline hole 106, and flows out from the infiltration hole 200, forming a thin water film on the outer surface of the infiltration cover 20, so that the electrode surface is infiltrated with physiological saline, further avoiding the formation of scabs on the ablated tissue and reducing the loop impedance. Maintaining impedance balance allows the ablation process to continue until the target ablation volume is reached.

[0128] It is understandable that the processing method of the electrode 1 is often mechanical processing, and the size of the saline hole 106 thereon is difficult to be made very small, while the infiltration cover 20 can be processed in other ways, and the infiltration hole 200 thereon can be made into a hole with a very small diameter, so that the physiological saline flowing out of the infiltration hole 200 forms a water film on the surface of the electrode. Without considering the difficulty of processing the electrode 1, multiple saline holes 106 can be processed on the electrode 1, and all the saline holes 106 are evenly distributed on the surface of the electrode 1. In this way, the infiltration cover 20 can also be omitted.

[0129] The wetting cover 20 allows the cooling medium to be distributed on the outer surface of the wetting cover 20 to form a film. In order to facilitate processing and installation, a split structure can be adopted between the wetting cover 20 and the electrode.

[0130] In one embodiment, the wetting cover 20 is fixed on the electrode 1, mounted on the electrode 1 to rotate around the electrode axis, or mounted on the electrode 1 to slide along the electrode axis.

[0131] The immersion cover 20 is directly wrapped around the electrode during installation, or the immersion cover 20 only covers a partial area of ​​the electrode 1, and can be embedded in a predetermined area during installation. When the immersion cover 20 is fixedly connected to the electrode 1, the relative position relationship with the electrode 1 can be maintained by welding, a connector or a limiting structure.

[0132] The infiltration cover 20 can also be installed on the electrode 1 by rotating around the electrode axis. On the one hand, only axial limitation is required. On the other hand, the anisotropy of the outflow holes in the circumferential direction can be used to obtain the expected outflow direction by rotating the infiltration cover 20, and even the outflow holes in some areas can be closed.

[0133] The wetting cover 20 is slidably installed on the electrode 1 along the electrode axial direction. The anisotropy of the outflow holes in the axial direction can be used to adjust the outflow of heat exchange medium in different parts through the movement of the wetting cover 20, and even close the outflow holes in some areas.

[0134] In order to control the movement of the infiltration cover 20 relative to the electrode 1, in one embodiment, a driving component connected to the infiltration cover 20 is further provided to drive the relative movement between the infiltration cover 20 and the electrode 1. For example, a traction rope that can move axially relative to the sheath tube 2 or a sleeve that can rotate relative to the sheath tube 2 is used.

[0135] In one embodiment, one immersion cover 20 is installed on the electrode 1, or a plurality of immersion covers 20 are installed.

[0136] As for an infiltration hood 20, it can only cover a local area of ​​the periphery of the electrode 1 in the circumferential direction. For example, a trough is set on the outer wall of the electrode 1, and the outflow hole is located at the bottom of the trough. The infiltration hood 20 is embedded in the trough and has a slight gap with the bottom of the trough to facilitate the distribution of the heat exchange medium.

[0137] In the scheme of multiple wetting covers 20, each wetting cover 20 can be arranged along the electrode axial direction, circumferential direction, etc. to cover different areas of the electrode. When multiple wetting covers 20 are installed, each wetting cover 20 is independently fixed or movably installed, for example, some of the wetting covers 20 are fixed on the electrode 1, and some of the wetting covers 20 are slidably or rotatably installed on the electrode 1.

[0138] In one embodiment, a plurality of wetting covers 20 are installed on the electrode 1, and each wetting cover 20 moves independently relative to the electrode 1 or at least two wetting covers are linked to each other.

[0139] The same infiltration cover 20 can be an integral structure or a split structure, and the split structure is fixed by interlocking, etc. Independent setting means being fixed or moving independently, while linkage means that when one moves, it will drive or affect the other.

[0140] The wetting cover 20 may also be a circumferentially non-enclosed structure. In one embodiment, the wetting cover 20 is in the form of a sheet and only covers a partial area of ​​the periphery of the electrode 1 in the circumferential direction.

[0141] The sheet can be either a flat surface or a curved surface, and is fixed on the electrode 1 in an inlaid or semi-enclosed manner. Relative to the electrode 1, the infiltration cover 20 at least covers the outflow hole portion, and of course can also extend further to the periphery. In one embodiment, the infiltration cover 20 is a circumferentially closed cylindrical structure, which is sleeved on the outer periphery of the electrode 1.

[0142] The tubular structure of the soaking cover 20 can be axially sleeved on the electrode 1 from the proximal side or the distal side of the electrode during installation. The circumferential closure can make the soaking cover 20 wrap around the electrode 1, but it is not required to wrap all parts of the electrode in the axial direction. For example, in one embodiment, the soaking cover 20 only wraps the proximal part of the electrode 1.

[0143] In one embodiment, the infiltration cover 20 is a cap-shaped structure, and the distal end of the cap-shaped structure closes and wraps the distal end of the infiltration cover 20 .

[0144] In order to facilitate the positioning and installation of the infiltration cover 20, in one embodiment, the infiltration cover 20 is fixed on the electrode 1, and a positioning step is provided on the periphery of the electrode 1, and the distal end of the infiltration cover 20 is abutted against the positioning step for limiting position.

[0145] In order to make the outer wall of the distal end of the radiofrequency ablation catheter smooth and even, in one embodiment, the outer wall of the infiltration cover 20 and the outer wall of the electrode 1 exposed to the infiltration cover 20 are spliced ​​at the same height. This avoids sudden changes in local shape or ridges, etc., and reduces safety hazards.

[0146] At least a portion of the infiltration cover 20 is a permeation area with infiltration holes 200 distributed thereon. The location of the outflow hole on the electrode corresponds to the permeation area and a gap is left between the location and the inner wall of the permeation area.

[0147] The gap can distribute the heat exchange medium and improve the uniformity of the heat exchange medium protective film. The gap can be formed by local sedimentation of the outer wall of the electrode or local bulge of the infiltration cover, or a combination of multiple methods.

[0148] In one embodiment, the wetting hole 200 is staggered with the outflow hole.

[0149] The staggered arrangement should at least avoid one-to-one alignment, which can prevent the heat exchange medium from preferentially flowing out of the infiltration holes directly opposite to the outflow holes, affecting the distribution effect of the infiltration cover 20. Similarly, the preferred mode is that the number of infiltration holes 200 is large and the aperture is smaller than that of the outflow holes.

[0150] Combination Fig.10b In one embodiment, a sedimentation zone 107 is provided on the outer wall of the electrode 1, the outflow hole is provided in the sedimentation zone 107, the infiltration zone of the infiltration cover 20 is located at the periphery of the sedimentation zone 107, and a gap is left between the inner wall of the infiltration cover 20 and the surface of the sedimentation zone 107.

[0151] The heat exchange medium output from each outflow hole can be further uniformly distributed by setting the settling area 107, and then seep out through the infiltration cover 20 after distribution. The size of the above gap can affect the pressure or flow rate of the heat exchange medium at different parts of the infiltration cover 20. In order to obtain uniform heat exchange medium output at the periphery of the infiltration cover 20, for example, to form a uniform physiological saline film, the distance from the adjacent outflow holes is different, and the gap also changes accordingly.

[0152] Combination Fig.10d In one embodiment, the outflow hole is flared, and the flared area serves as a sedimentation area; the gap between the inner wall of the infiltration cover and the surface of the sedimentation area decreases as the distance from the outflow hole increases.

[0153] The flared shape (trumpet-shaped opening) is for uniform output of the heat exchange medium. For example, when the heat exchange medium flows at a fast rate, it is easy to be ejected directly from the nearest infiltration hole, so that the infiltration holes far away from the outflow hole and the infiltration holes close to the outflow hole cannot uniformly output the heat exchange medium, affecting the uniformity of the heat exchange medium protective film.

[0154] Fig.10d In the embodiment, the opening of the outflow hole, i.e., the brine hole 106, on the outer wall of the electrode 1 is in the form of a flared opening, and the flared area is used as the sedimentation area 107. The gap between the inner wall of the infiltration cover 20 and the surface of the sedimentation area decreases as the distance from the outflow hole increases. The flared opening can increase the distance between the outflow hole and the infiltration hole facing it, alleviate the jetting phenomenon, and make the infiltration holes at different distances from the outflow hole output the heat exchange medium uniformly. For another example, when the flow rate of the heat exchange medium is relatively slow, the infiltration holes far away from the outflow hole have a smaller flow rate than the infiltration holes close to the outflow hole due to insufficient supply. Therefore, in one embodiment, the gap between the inner wall of the infiltration cover 20 and the surface of the sedimentation area increases as the distance from the outflow hole increases.

[0155] After the heat exchange medium transported from the outflow hole is distributed in the sedimentation area, the gap far away from the outflow hole is large, which can ensure sufficient heat exchange medium supply, so that the flow of each infiltration hole is relatively balanced as a whole, forming a uniform heat exchange medium protective film.

[0156] If there are multiple outflow holes around a certain area between the inner wall of the infiltration cover 20 and the surface of the sedimentation area, the distance between the area and the outflow hole can take into account the multiple adjacent outflow holes, for example, it can be calculated according to the average distance.

[0157] In one embodiment, there is one or multiple sedimentation zones isolated from each other, and one outflow hole is provided in the same sedimentation zone. In the same sedimentation zone, the gap between the inner wall of the infiltration cover 20 and the surface of the sedimentation zone increases with the increase of the distance from the outflow hole in the sedimentation zone.

[0158] Combination Fig.10b For example, the corresponding brine hole 106 of the sedimentation area 107 has different depths in areas at different distances from the brine hole 106 . The farther away from the brine hole 106 , the deeper the sedimentation area 107 is.

[0159] For the convenience of calculation and processing, in one embodiment, the sedimentation zone is a distribution groove extending along the axial direction of the electrode, and the outflow holes (such as the brine holes 106 in the figure) are divided into several groups around the electrode, and each group corresponds to the same distribution groove.

[0160] That is, the outflow holes of the same group are opened at the bottom of the same distribution groove, and the depth of the distribution groove can be regarded as the gap size between the inner wall of the infiltration cover 20 and the surface of the sedimentation area.

[0161] In conjunction with the accompanying drawings, in one embodiment, the number of the distribution grooves is 2 to 10, for example 4, 6, 8, etc., which are evenly arranged in the circumferential direction, and the infiltration cover 20 is cylindrical and wraps around the periphery of all the distribution grooves.

[0162] The number of outflow holes in the same group can be one or a plurality of holes arranged in sequence, for example, there is one salt water hole 106 in the figure.

[0163] In one embodiment, a flow hole is opened at the bottom of the same distribution groove, and the depth of the distribution groove increases with the increase of the distance from the flow hole.

[0164] In one embodiment, a plurality of groups of wetting holes 200 are distributed circumferentially on the wetting cover 20 , and each group of wetting holes 200 corresponds to the position of one of the distribution slots.

[0165] When mechanical processing is adopted, the infiltration holes 200 corresponding to the same distribution groove can be arranged in sequence in one or more, such as 4 to 10 in the figure. If weaving or porous materials are used, the number and distribution of the infiltration holes 200 are relatively complex. Therefore, the grouping principle mainly considers the corresponding relationship with the distribution groove.

[0166] The groove walls of adjacent distribution grooves form ridges that support the inner wall of the infiltration hood 20 , and the tops of the ridges abut against corresponding portions of the inner wall of the infiltration hood 20 and match in shape.

[0167] For example, the infiltration cover 20 is a cylinder, and the infiltration cover 20 is a curved surface, and the curvature corresponds to the infiltration cover 20, so that better support can be obtained and unnecessary local deformation of the infiltration cover 20 can be reduced.

[0168] The wetting cover 20 is provided with wetting holes 200 . According to different processing methods of the wetting cover 20 , the wetting holes 200 also have corresponding distribution characteristics and shapes.

[0169] In one embodiment, the wetting cover 20 is made of porous material, and the gaps in the porous material itself serve as the wetting holes 200 .

[0170] The porous material can be embedded in a part of the electrode 1 or made into a cylindrical or cap-shaped sleeve on the electrode 1, at least covering the infiltration holes 200 at the expected position. As for the porous material itself, existing technologies such as foam metal can be used.

[0171] In one embodiment, the infiltration cover 20 adopts a woven structure, and the gaps in the woven structure itself serve as the infiltration holes 200 .

[0172] When weaving, for example, fiber materials are used to interweave warp and weft, and there are gaps between the warp and weft, that is, they serve as the infiltration holes 200. The fiber material can be, for example, nickel-titanium alloy.

[0173] In one embodiment, the wetting cover 20 is a metal shell, and the wetting hole 200 is formed on the shell wall of the metal shell.

[0174] The pore size and density distribution of the infiltration holes can be set according to the flow requirements of the heat exchange medium to ensure that a uniform protective film is formed around the electrode as much as possible. For example, the pore size of all the infiltration holes is the same, or they can be set accordingly based on the balance of the heat exchange medium flow.

[0175] That is, the diameters of the infiltration holes in different areas can be varied to meet the needs of balanced flow. Similarly, the distribution density of all the infiltration holes in different parts of the equalization device is the same, or they are set accordingly according to the balance of the heat exchange medium flow.

[0176] When setting accordingly according to the heat exchange medium flow balance, the arrangement of the heat exchange medium flow channel outlet is mainly considered, for example, the aperture of the wetting hole increases with the increase of the distance from the outflow hole.

[0177] Similarly, for example, the distribution density of the infiltration pores increases with the distance from the outflow pores.

[0178] The wetting holes may be arranged as desired during processing. For example, in one embodiment, a plurality of wetting holes 200 are distributed in a circumferential direction of the wetting cover 20 .

[0179] For example, there are 2 to 6 groups, each group of which has 2 or more infiltration holes, for example, 4 to 10. The groups can be divided according to the arrangement trend and the corresponding relationship with the heat exchange medium flow channel.

[0180] The same group of infiltration holes 200 are arranged in sequence according to their respective extension paths, and the extension path is a straight line, a broken line or a curve. When it is a straight line, it can be regarded as the same group of infiltration holes 200 being arranged in sequence along the axial direction. When it is a curve, the overall trend can be extending along the axis, and the specific path can be an arc, an S-shaped curve, etc.

[0181] In other embodiments, all the infiltration holes 200 may be distributed along a spiral line around the electrode axis, or the infiltration holes 200 may be evenly distributed in an array.

[0182] In order to make the infiltration cover 20 discharge water evenly and form a uniform water film, in one embodiment, the aperture (which can be understood as the size of the cross-sectional area) of the same group of infiltration holes 200 increases with the increase of the distance from the outflow hole.

[0183] If there are multiple outflow holes around each infiltration hole 200 in the same group of infiltration holes 200, only the closest outflow hole may be considered or calculated according to the average distance. In one embodiment, each group of infiltration holes 200 corresponds to one outflow hole. In this case, the change in the aperture of the infiltration holes 200 in the same group may only consider the outflow holes corresponding to the circumferential position.

[0184] 10 , for example, multiple infiltration holes such as infiltration hole 201 and infiltration hole 202 correspond to the saline hole 106 in circumferential position. Infiltration hole 202 is farther away from the saline hole 106 than infiltration hole 201 , and the aperture of infiltration hole 202 is correspondingly larger than that of infiltration hole 201 .

[0185] In one embodiment, the immersion mask 20 has a developing mark.

[0186] At least a portion of the infiltration cover 20 itself is a developing material or a developing mark is installed on the infiltration cover 20, and the developing mark can cooperate with an imaging device to display the position of the electrode 1 during surgery.

[0187] The shape of the developing mark itself is not strictly limited, for example, it can be a ring extending along the circumferential direction, a C-shape, or a strip extending along a predetermined direction.

[0188] In one embodiment, the developing marks on the immersion cover 20 are arranged in a plurality of places in sequence along the axial direction. The developing marks are arranged in a plurality of places in sequence along the axial direction, which makes it easier to identify the spatial posture. For example, the relative inclination degree with respect to the viewing angle can be determined according to the length of the developing mark arrangement line, or the spatial position of the electrode can be located in combination with the curvature of the developing mark arrangement line.

[0189] In one embodiment, the radiofrequency ablation catheter further includes an electromagnetic navigation component capable of indicating the position of the electrode.

[0190] As for the electromagnetic navigation component itself, existing technology can be used. A mounting hole can be opened in the electrode to accommodate the electromagnetic navigation component, or the electromagnetic navigation component can be attached and fixed to the outside of the electrode. During the intervention and ablation process, the position of the electromagnetic navigation component in the body can be sensed by imaging equipment, and the electrode position or posture can be obtained to guide and monitor the ablation operation.

[0191] During the ablation procedure, the electrode sometimes needs to be adjusted in its direction or spatial posture while it is moving in the body, usually by pulling it at the distal end using a pull wire.

[0192] A radiofrequency ablation catheter according to one embodiment includes an electrode 1 , to which a pull wire 10 extending toward the proximal end is connected for driving the electrode 1 to deflect.

[0193] The use of the pull wire 10 is more conducive to adjusting the electrode 1, and on this basis, the aforementioned related features (or implementation methods) such as the infiltration cover 20 can also be combined. For example, the electrode 1 has a heat exchange medium flow channel inside, and the outer wall of the electrode 1 is provided with an outflow hole connected to the heat exchange medium flow channel. The infiltration cover 20 is installed on the electrode 1 and is located outside the outflow hole. The heat exchange medium output from the outflow hole flows out through the infiltration cover 20.

[0194] In order to introduce heat exchange medium into the electrode 1, a connecting pipe connected to the heat exchange medium flow channel is provided at the proximal end of the electrode 1. The interior of the connecting pipe can also be regarded as a part of the heat exchange medium flow channel. The connecting pipe and the electrode can be an integrated structure for docking with an external pipeline and extending toward the proximal end.

[0195] In one embodiment, the proximal end of the electrode is connected to a sheath 2 made of elastic material, and the pull wire 10 extends from the inside of the sheath 2 to the proximal end to the outside of the sheath 2; the proximal end of the electrode 1 is provided with a connecting pipe connected to the heat exchange medium flow channel, and the connecting pipe extends to the inside of the sheath 2.

[0196] In order to install the pull wire 10 to facilitate the control of the electrode 1, in one embodiment, one end of the electrode 1 is connected to a sheath 2 made of elastic material, a saline connecting tube 101 extends into the interior of the sheath 2, and the pull wire 10 is fixedly arranged on the electrode 1. The pull wire 10 extends from the interior of the sheath 2 to the exterior of the sheath 2, so that when the pull wire 10 is pulled, the sheath 2 bends and deforms, thereby driving the electrode 1 to deflect.

[0197] The pull wire 10 extends from the inside of the sheath 2 to the sheath 2, which can be understood as extending proximally inside the sheath 2 until extending out of the proximal end of the sheath 2. Of course, it can also radially penetrate the wall of the sheath 2 along the sheath 2 near the proximal end of the sheath 2, that is, extend to the outside of the sheath 2.

[0198] In one embodiment, the radiofrequency ablation catheter further includes a first bending component 4 and a second bending component 5 that can be relatively close to or far away from each other, the sheath 2 is fixed to the first bending component 4, and the pull wire 10 is fixed to the second bending component 5.

[0199] That is, the handle part also includes a first bending component 4 and a second bending component 5 slidably matched with the first bending component 4 , and the electrode 1 is controlled to deflect toward the target position through relative movement of the first bending component 4 and the second bending component 5 .

[0200] The first stretch-bending component 4 and the second stretch-bending component 5 can be a single component or a combination of multiple components, and they can even be different parts of the same component.

[0201] In one embodiment, the first stretch-bending assembly 4 and the second stretch-bending assembly 5 are arranged to slide in a nested manner or in a side-by-side manner. Necessary guide and limit structures may be provided to improve the stability of the relative movement.

[0202] In order to fix the proximal end of the pull wire 10, in one embodiment, a mounting hole is provided on the electrode 1, and the distal end of the pull wire 10 is inserted into and fixed to the mounting hole. The mounting hole can prevent the pull wire end from being exposed, and improve the connection strength. When fixing, welding, bonding or a combination can be used, or an anchor can be fixed to the pull wire end, and the anchor is interference-fitted with the mounting hole. Or the pull wire end is fixed to the electrode 1 through an intermediate connector.

[0203] The opening of the mounting hole is located at the proximal end of the electrode. To improve the connection strength, the mounting hole can be extended a distance toward the distal end along the electrode axis, and the pull wire 10 can be further inserted to the bottom of the mounting hole toward the distal end.

[0204] In the figure, one end of the pull wire 10 is fixed in the second mounting hole 103 on the electrode 1, and the other end is extended along the sheath 2 and fixed to the second bending assembly 5. When the first bending assembly 4 and the second bending assembly 5 are relatively moved, the pull wire 10 is pulled, so that the sheath 2 is pulled and bent, thereby deflecting the electrode 1 at the end of the sheath 2. In some embodiments, a spring hose 11 is also sheathed outside the pull wire 10. When the pull wire 10 is pulled, the spring hose 11 can bend and deform with the sheath 2, and rebound after the pull on the pull wire 10 is released.

[0205] When the pull wire 10 is tightened, it may exert a large pressure on other surrounding components or even cut them. The spring hose 11 can further play a buffering and protective role.

[0206] like Figure 4 As shown in Fig. 7, the sheath tube 2 extends from one end of the electrode 1 toward the handle portion and is fixed to the first bending assembly 4. The sheath tube 2 is made of a material with a certain elasticity so that it can undergo a recoverable bending elastic deformation, thereby controlling the deflection of the electrode 1.

[0207] In some embodiments, in order to strengthen the connection between the sheath 2 and the first bending assembly 4 , a protective tube 3 is sleeved and fixed on the connector 402 of the first bending assembly 4 , and a portion of the protective tube 3 extends to the outside of the sheath 2 .

[0208] In one embodiment, the first stretch-bending component 4 and the second stretch-bending component 5 are both tubular, and the second stretch-bending component 5 is slidably fitted in the first stretch-bending component 4 .

[0209] A sliding chamber 401 is formed inside the first bending assembly 4. The sliding chamber 401 is opened at one end away from the fixed end of the sheath tube 2. The second bending assembly 5 is slidably connected to the sliding chamber 401 from the opening. The part of the second bending assembly 5 that is slidably connected to the sliding chamber 401 constitutes a sliding tube body 501. A wire passing cavity 500 is formed in the sliding tube body 501. The pull wire 10, the guide wire 16, etc. extending from the sheath tube 2 all pass through the wire passing cavity 500. An end cap 14 is provided at one end of the second bending assembly 5 that is away from the fixed end of the sheath tube 2. The wire passing through the wire passing cavity 500 passes through the end cap 14 and is respectively connected to the saline connector 6 and the ablator connector 7.

[0210] A bolt hole 503 is provided on the outer wall of the second bending assembly 5, and a pull wire fixing bolt 13 is screwed on the bolt hole 503. The pull wire 10 is fixed to the second bending assembly 5 by the pull wire fixing bolt 13. In this way, when the sliding tube body 501 slides in the sliding chamber 401, the end of the pull wire 10 away from the electrode 1 moves with the sliding tube body 501, thereby pulling the sheath tube 2 to bend, and driving the electrode 1 installed at the end of the sheath tube 2 to deflect.

[0211] In some embodiments, at least a portion of the second stretch-bending assembly 5 is embedded in the first stretch-bending assembly 4 , and a guide device is further provided between the first stretch-bending assembly 4 and the second stretch-bending assembly 5 to limit the movement directions of the two.

[0212] A guide device is provided between the first stretch-bending assembly 4 and the second stretch-bending assembly 5 to limit the sliding tube body 501 to only undergo axial relative displacement in the sliding chamber 401 without undergoing relative rotation.

[0213] In some embodiments, the guiding device includes a slide groove 502 provided on either the first stretch-bending component 4 or the second stretch-bending component 5 and a limit screw 403 provided on the other one.

[0214] Specifically, the first bending assembly 4 is provided with a stop screw 403 extending to the sliding chamber 401. A slide groove 502 is provided on the outer wall of the sliding tube body 501. When the second bending assembly 5 is slidably connected to the sliding chamber 401 on the first bending assembly 4, the stop screw 403 is at least partially located in the slide groove 502. In this way, the relative movement direction of the first bending assembly 4 and the second bending assembly 5 is limited by the sliding stop effect of the stop screw 403 on the slide groove 502. The length of the slide groove 502 also limits the maximum bending degree of the sheath tube 2.

[0215] Those skilled in the art can understand that there are many ways to limit the relative movement direction of the first stretch-bending assembly 4 and the second stretch-bending assembly 5, and are not limited to the above-mentioned form of cooperation between the limit screw 403 and the slide groove 502.

[0216] In some embodiments, an O-ring 15 for increasing the friction between the first stretch-bending component 4 and the second stretch-bending component 5 is provided on the portion of the second stretch-bending component 5 embedded in the first stretch-bending component 4 .

[0217] For example, a groove 504 surrounding the sliding tube body 501 is provided on the outer wall of the sliding tube body 501, and an O-ring 15 is installed in the groove 504. In this way, when the first bending component 4 and the second bending component 5 slide relative to each other, the O-ring 15 can appropriately increase the contact friction between the sliding tube body 501 and the sliding chamber 401 to increase the feel of the relative movement of the two bending components. In this way, when controlling the deflection angle of the electrode 1, since a certain force is required to pull the pull wire 10, it will be easier to control the distance that the pull wire 10 is pulled, thereby more accurately controlling the bending degree of the sheath 2 and correspondingly more accurately controlling the deflection angle of the electrode 1.

[0218] In order to further improve the convenience of driving the relative movement between the first bending assembly 4 and the second bending assembly 5, the first bending assembly 4 is preferably provided with two finger rings 400, and the second bending assembly 5 is also provided with a finger ring 400, and the operator's fingers can pass through the finger rings 400 to form a fixation with any bending assembly, so as to facilitate the relative movement of the two bending assemblies, and also facilitate single-handed operation.

[0219] In order to further improve the accuracy of driving the relative movement between the first stretch-bending assembly 4 and the second stretch-bending assembly 5 , in one embodiment, a scale line indicating the relative position of the second stretch-bending assembly 5 to the first stretch-bending assembly 4 is provided on the second stretch-bending assembly 5 .

[0220] In one embodiment, a thermistor 9 for detecting the real-time temperature of the electrode 1 is further provided in the electrode 1 , and the thermistor 9 is electrically connected to the ablation device via a thermistor wire 90 .

[0221] The thermistor 9 is fixed on the electrode 1 and is used to obtain temperature data of the ablated tissue in real time, and transmit the temperature data to the ablation device via a thermistor wire 90 connected from the thermistor 9 to the ablation device connector 7 .

[0222] In one embodiment, a temperature control sleeve 91 is further disposed in the sheath tube 2 and is sleeved outside the thermistor wire 90 .

[0223] That is, in order to prevent the thermistor wire 90 from being disturbed, a temperature control sleeve 91 is further provided on the outside thereof, and the temperature control sleeve 91 is sleeved on the outside of the thermistor wire 90 .

[0224] In one embodiment, an electrode ring 8 is further disposed outside the sheath tube 2 , and a temperature sensor 19 connected to the electrode ring 8 and capable of detecting the temperature of the electrode ring 8 is disposed inside the sheath tube 2 , and the temperature sensor 19 is electrically connected to the ablation device.

[0225] An electrode ring 8 is provided on the outer wall of the sheath 2 at a position about 2 cm away from the electrode 1. A through hole is provided on the outer wall of the sheath 2 corresponding to the position where the electrode ring 8 is provided, and the through hole is connected to the inner cavity of the sheath 2. A forked rivet tube 18 is provided in the sheath 2, and a portion of the forked rivet tube 18 passes through the through hole and is welded and fixed to the electrode ring 8, and the portion of the forked rivet tube 18 located in the inner cavity of the sheath 2 is connected to the temperature sensor 19. The temperature sensor 19 is electrically connected to the ablation device connector 7, so that the temperature sensor 19 senses the temperature of the electrode ring 8 through the forked rivet tube 18 and transmits the temperature to the ablation device. During the ablation process, when the ablation range reaches the electrode ring 8 (generally the ablation diameter is 2 cm), the temperature detected by the temperature sensor 19 reaches the preset value. At this time, it can be judged that the ablation range has reached the preset value, and the ablation device can stop outputting energy to the electrode 1, thereby stopping the ablation process. It will be understood by those skilled in the art that, according to actual needs, the position of the electrode ring 8 can be moved along the sheath tube 2 and the preset temperature can be changed accordingly, so that the ablation radius can be controlled, thereby effectively controlling the size of the ablation area.

[0226] The electrode ring 8 can be a closed whole ring structure in the circumferential direction, or a non-closed structure, such as a C-shape or a corresponding smaller wrap angle. In order to facilitate installation, the electrode ring 8 can be in the form of a patch. The patch shape is not strictly limited and is fixed to the outer wall of the electrode by welding or other methods. The electrode ring 8 is a heat-conducting element, and the temperature sensor 19 can also be a thermistor or other methods in the circuit to sense the temperature through the change of the electrical signal.

[0227] In the prior art, the ablation effect is difficult to judge directly, and is mostly evaluated through surgery, lacking intraoperative judgment or evaluation methods. In the present application, a radiofrequency ablation catheter in one embodiment has multiple temperature detection devices distributed in sequence along the axial direction near the distal end of the radiofrequency ablation catheter.

[0228] Multiple temperature detection devices can collect the temperature around the electrode 1. During the ablation process, the temperature around the electrode changes in a gradient. It is possible to obtain (real-time monitoring) the temperature at the center of the ablated cell and the ablation status of the cell edge.

[0229] The multiple temperature detection devices can be implemented separately or in combination with one or more of the above-mentioned pull wire 10 and the infiltration cover 20 and related features (or implementations). For example, the pull wire 10 extending toward the distal end is connected to the electrode 1 to drive the electrode 1 to deflect. By monitoring the temperature, the electrode 1 can be driven to deflect by the pull wire 10 when necessary.

[0230] For another example, the electrode 1 has a heat exchange medium flow channel inside, and an outflow hole connected to the heat exchange medium flow channel is opened on the outer wall of the electrode 1. An infiltration cover 20 is installed on the electrode 1 and is located outside the outflow hole. The heat exchange medium output from the outflow hole flows out through the infiltration cover 20. By monitoring the temperature, the heat exchange medium output can be adjusted in time, and a heat exchange medium protective film can be formed through the infiltration cover 20.

[0231] For example, 2, 3 or more temperature detection devices may be provided, and the collected temperature signals may be displayed in real time in a visual manner to guide the ablation operation, thereby effectively controlling the ablation range and directly judging or estimating the ablation effect during the operation.

[0232] In one embodiment, a temperature detection probe is provided at the distal end of the electrode 1. The temperature of the distal end of the electrode 1 can be collected. During ablation, the distal end of the electrode 1 can be extended to the position corresponding to the center of the lesion. The relative position relationship and relative temperature relationship of other temperature detection devices are all based on the distal end of the electrode 1 for intuitive comparison.

[0233] The temperature detection probe may be connected to the ablation apparatus in a wireless or wired manner. For example, a mounting groove may be provided at the distal end of the electrode 1, and the temperature detection probe is embedded in the mounting groove.

[0234] When connected by wire, a wire channel (avoiding the heat exchange medium channel) can be opened inside the electrode 1 to guide the wire between the electrode 1 and the ablation device.

[0235] In order to facilitate the installation of the temperature detection device and the detection of temperature, the direct temperature sensing element in the temperature detection device (such as the electrode ring 8) should be arranged outside the electrode 1 or exposed to the electrode 1. Unless otherwise specified below, the description of the axial relative position between the temperature detection device and the electrodes should be understood as a direct temperature sensing element, such as a heat-conducting element in the form of a ring, sheet, column, etc., which is used to transfer the temperature to the temperature sensor (thermistor, etc. can be used in the circuit). The temperature sensor itself can also be directly exposed to the electrode 1 (i.e., the outside of the radiofrequency ablation catheter) as a temperature sensing element. The specific shape is not strictly limited. Of course, some preferred or improved implementations are also provided below.

[0236] In one embodiment, the proximal end of the electrode 1 is connected to a sheath tube 2 or a metal tube 21 , and the temperature detection device is installed outside the electrode 1 , or outside the sheath tube 2 , or outside the metal tube 21 .

[0237] The sheet-shaped or columnar temperature detection device can be embedded in the outer wall of the electrode 1, and the annular temperature detection device can be fixed around the electrode 1, the sheath 2 or the metal tube 21. The annular temperature detection device can be a circumferentially closed ring or a non-closed one (e.g., C-shaped).

[0238] The temperature detection device can be installed either flexibly or fixedly, see Fig.18c In one embodiment, when fixedly installed, the temperature detection device includes a temperature sensor (omitted in the figure), and the outer wall of the radiofrequency ablation catheter 211 is provided with a embedding groove 212, the temperature sensor is fixed in the embedding groove 212 at a corresponding position, and the bottom of the embedding groove 212 is provided with a first through hole 213 for passing the circuit wire.

[0239] The fixedly installed temperature detection device may be any one or more. The above installation method is for one of them. When multiple temperature detection devices are fixedly installed, the specific installation and fixing methods may be the same or different.

[0240] Depending on the position of the temperature detection device, the radiofrequency ablation catheter 211 in the figure may be a part of the electrode 1, sheath 2 or metal tube 21 in the aforementioned embodiments. The depth of the embedding groove 212 corresponds to the radial dimension of the temperature sensor, and the shape of the embedding groove 212 corresponds to the temperature sensor, that is, the temperature sensor can fill and fill the embedding groove 212 to avoid unnecessary gaps.

[0241] In one embodiment, the embedding groove 212 is annular, and the temperature sensor is fixed in the embedding groove 212 at the corresponding position. The fixing method between the temperature sensor and the embedding groove 212 is selected from at least one of bonding, welding, riveting, and interference fit. For example, in the figure, the embedding groove 212 surrounds the radiofrequency ablation catheter 211, and the corresponding temperature sensor is annular, and its fixing method is not limited to one or more. Of course, the embedding groove 212 can also be a non-closed structure in the circumferential direction, such as a C shape.

[0242] The temperature sensor can be in the form of a patch, and directly exposed as a temperature sensing element on the outer wall of the radiofrequency ablation catheter 211, so that the temperature signal can be collected more timely and accurately.

[0243] When the temperature sensor area or volume is small, in order to facilitate installation, Figure 18b to Figure 18d In one embodiment, the temperature detection device includes a temperature sensor (omitted in the figure) and a thermally conductive ring 214. The temperature sensor is connected to the ablation device. The thermally conductive ring 214 is arranged on the outer wall of the radiofrequency ablation catheter 211. The temperature sensor is thermally coupled to the thermally conductive ring 214.

[0244] The thermal coupling can be direct contact or indirect contact, mainly to transfer temperature between the two. The heat-conducting ring 214 itself is not strictly limited to a complete ring, and can be a part extending in the circumferential direction. A complete ring is a circumferentially closed shape, such as a circular ring, while a part extending in the circumferential direction is not closed in the circumferential direction, such as a C-shape.

[0245] In one embodiment, the temperature sensor is fixed to the outer wall of the heat-conducting ring by at least one of bonding, welding, riveting and interference fit.

[0246] In one embodiment, the temperature sensor is a thermistor, which is electrically connected to the ablation device through a thermistor wire, and a temperature control sleeve is provided on the thermistor wire. The temperature control sleeve can prevent the thermistor wire from being disturbed, and the temperature control sleeve is tightly attached to the thermistor wire as a whole and is located inside the radiofrequency ablation catheter.

[0247] To facilitate transmission, circuit wires are omitted. In one embodiment, the temperature sensor is connected to the ablation device via a wireless communication device.

[0248] In one embodiment, an embedding groove 212 is provided on the outer wall of the radiofrequency ablation catheter 211, and the temperature detection device is fixed in the embedding groove 212 at a corresponding position; and a through hole for passing the circuit wire is provided at the bottom of the embedding groove 212.

[0249] A first through hole 213 is provided at the bottom of the embedding groove 212. In the temperature detection device, a portion of the thermally conductive ring 214 is sunk into the first through hole 213. A second through hole 216 is provided on the sunken portion of the thermally conductive ring 214. The circuit wire of the temperature sensor enters the interior of the radiofrequency ablation catheter 211 through the second through hole 216 and extends toward the proximal end.

[0250] In order to facilitate the positioning of the heat-conducting ring 214 and prevent rotation or axial dislocation, in one embodiment, the groove 212 is annular, and the temperature detection device is fixed in the corresponding groove 212; the fixing method between the temperature detection device and the groove 212 is selected from at least one of bonding, welding, riveting, and interference fit.

[0251] In one embodiment, the heat-conducting ring 214 is an annular structure, and the heat-conducting ring 214 is disposed in the embedding groove 212. The heat-conducting ring 214 is a complete annular structure, and the temperature sensor is further fixed on the inner wall or the outer wall of the heat-conducting ring 214.

[0252] In one embodiment, the temperature detection device is annular in structure, and the heat-conducting ring 214 and the temperature sensor are complementary in shape in the circumferential direction to form the annular structure. In this embodiment, the heat-conducting ring 214 and the temperature sensor are spliced ​​together in the circumferential direction to form a complete ring, for example, both are semicircular in shape, and for example, the heat-conducting ring 214 is C-shaped, and the temperature sensor fills the gap of the C-shaped, that is, they are complementary.

[0253] In one embodiment, a groove 215 is formed on the heat conductive ring 214, and the temperature sensor is fixed in the groove 215. The fixing method between the temperature sensor and the groove 215 is selected from at least one of bonding, welding, riveting, and interference fit.

[0254] A portion of the heat-conducting ring 214 is sunk into the first through hole 213 , and a sinking groove 215 is correspondingly formed on the outer side of the heat-conducting ring 214 . The temperature sensor fills the sinking groove 215 to avoid unnecessary gaps.

[0255] In order to make the outer surfaces of the electrode 1 and the sheath tube 2 smooth and avoid ridges, in one embodiment, the outer surface of the temperature detection device is flush with the periphery.

[0256] In one embodiment, at least one temperature detection device is located in the middle of the electrode 1 in the axial direction.

[0257] During ablation, a temperature field is formed with the electrode as the center. At least one temperature detection device is located in the center of the temperature field. On the one hand, it can sense the temperature changes in the area. On the other hand, in conjunction with other temperature detection devices, the distribution of the above temperature field can be further calibrated and clarified based on the difference between them.

[0258] In one embodiment, at least one temperature detection device is fixed around the outer circumference of the radiofrequency ablation catheter.

[0259] The specific location where the temperature detection device is wound may be the electrode 1 , the sheath tube 2 or the outer wall of the metal tube 21 .

[0260] In one embodiment, a temperature detection probe is provided at the distal end of the electrode, which is used as one of the temperature detection devices to collect distal temperature information, and the remaining temperature detection devices include a first temperature detection device, a second temperature detection device and a third temperature detection device arranged at intervals from the distal end to the proximal end.

[0261] in:

[0262] A first temperature detection device, adjacent to the distal end of the electrode 1;

[0263] The second temperature detection device is wound and fixed on the outside of the electrode 1, the sheath tube 2 or the metal tube 21 and is located at the proximal end of the first temperature detection device;

[0264] The third temperature detection device is wound and fixed on the outside of the electrode 1, the sheath tube 2 or the metal tube 21, and is located at the proximal end of the second temperature detection device.

[0265] For example, the first temperature detection device is sheet-shaped or columnar, and the second temperature detection device and the third temperature detection device are both annular. The sheet-shaped structure can be fixed on the outer wall of the electrode 1, the sheath tube 2 or the metal tube 21 in the form of a patch.

[0266] Depending on the axial length of the electrode 1, when the electrode 1 is shorter, the second temperature detection device and the third temperature detection device are both located outside the sheath 2 or the metal tube 21; when the electrode 1 is slightly longer, the second temperature detection device is located outside the electrode 1, and the third temperature detection device is located outside the sheath 2 or the metal tube 21; when the electrode 1 is further lengthened, the second temperature detection device and the third temperature detection device are both located outside the electrode 1.

[0267] See also Fig.18a The detection position corresponding to the temperature detection probe at the distal end of electrode 1 is A0, the detection position corresponding to the first temperature detection device is A1, the detection position corresponding to the second temperature detection device is A2, and the detection position corresponding to the third temperature detection device is A3.

[0268] A0 can also be regarded as the heating center, that is, the part with the highest temperature. The farther away from A0, the lower the temperature will be. For example, the temperature in the area with a radius of R1 (e.g. 1 cm) can reach 100°C, and the edge temperature of the area with a radius of R2 (e.g. 1.5 cm) can generally reach 43-60°C, which can still meet the needs of ablation treatment. The edge temperature of the area with a radius of R3 (e.g. 2 cm) is further reduced and cannot meet the needs of ablation treatment. It is only for monitoring and reference.

[0269] In order to match the temperature field with the volume of the lesion, when multiple temperature detection devices are used, the multiple temperature detection devices can be fixed in advance, that is, radiofrequency ablation catheters of different specifications are configured according to different spacings. In actual application, the appropriate specifications are selected according to the pre-known volume of the lesion.

[0270] The shapes and sizes of the lesions to be ablated are different. To improve versatility, in one embodiment, the axial position of at least one temperature detection device is adjustable.

[0271] Changing the position of the temperature detection device means changing the detection position relative to the distal end of the electrode. For example, the axial position of the second temperature detection device in the above embodiment is adjustable, or the axial positions of both the second temperature detection device and the third temperature detection device are adjustable.

[0272] Combination Fig.18a When the axial position of the second temperature detection device changes, the distance between A1 and A2 changes, that is, R2 changes. The same applies to the axial position of the third temperature detection device. By changing the position of the temperature detection device, the temperature detection position or monitoring area can be changed to adapt to the size of the lesion.

[0273] In order to facilitate the movement of the temperature detection device, in one embodiment, a mutually cooperating guide structure is provided between the radiofrequency ablation catheter and the temperature detection device.

[0274] For example, in one embodiment, the outer wall of the electrode, sheath or metal tube is provided with a slide groove arranged along the axial direction, the temperature detection device is surrounded by the outer wall of the electrode, sheath or metal tube, and a protrusion matching the slide groove is provided on the inner wall of the temperature detection device.

[0275] The temperature detection device is guided to move by the cooperation between the protrusion and the slide groove, and is prevented from rotating relative to the electrode.

[0276] After the temperature detection device is in place, if it is fixed outside the body, the temperature detection device can be riveted and fixed to the electrode by applying local pressure using pliers of matching size, and it can also be fixed by welding or other methods.

[0277] If the temperature detection device also needs to be positioned in the body, the temperature detection device can be adjusted in a traction manner similar to the pull wire 10. For example, in one embodiment, a traction rope is connected to the axially adjustable temperature detection device, and the traction rope is used to drive the temperature detection device to change its axial position relative to the electrode 1.

[0278] In one embodiment, the traction rope penetrates into the interior of the radiofrequency ablation catheter from the temperature detection device to which it is connected, and extends toward the proximal end through the interior of the radiofrequency ablation catheter.

[0279] The interior of the radiofrequency ablation catheter can be the interior of an electrode, a sheath or a metal tube. The main part of the traction cable extends inside the radiofrequency ablation catheter to avoid contact with the body tissue and eliminate the potential safety hazard of cutting the tissue.

[0280] The traction cable extends toward the proximal end, that is, extends adjacent to the operator, to facilitate traction control. The proximal end of the traction cable may be configured with an adjustment component, and the traction cable is driven by operating the adjustment component. In one embodiment, the radiofrequency ablation catheter further includes a first adjustment component and a second adjustment component capable of relative movement, wherein the electrode 1 is relatively fixed to the first adjustment component, the traction cable is connected to the second adjustment component, and when the first adjustment component and the second adjustment component move relative to each other, the traction cable drives the temperature detection device connected thereto to change the axial position relative to the electrode 1.

[0281] When the first adjustment component and the second adjustment component move relative to each other, the spacing between at least some areas of the two will change, which can be axial or circumferential or at least have a component in a certain direction. The above-mentioned spacing change can be used to drive the traction rope to drive the temperature detection device.

[0282] In one embodiment, the first adjustment component and the second adjustment component are slidably engaged or rotationally engaged.

[0283] Sliding fit can be understood as axial relative movement; rotational fit can be understood as relative movement at least in the circumferential direction, such as axial limited rotation or threaded rotational fit.

[0284] Since the electrode 1 is relatively fixed to the first adjustment component, the first adjustment component can be combined with the aforementioned first stretching and bending component, or even be the same component, and the sheath 2 is fixed to the distal end side of the component.

[0285] For example, in one embodiment, the radiofrequency ablation catheter further includes a first bending component 4 and a second bending component 5 that can be relatively close to or far away from each other, the electrode 1 is relatively fixed to the first bending component 4, and a pull wire 10 is connected between the second bending component 5 and the electrode;

[0286] The radiofrequency ablation catheter further comprises a first adjustment component and a second adjustment component capable of relative movement, wherein the electrode 1 is relatively fixed to the first adjustment component, the traction cable is connected to the second adjustment component, and when the first adjustment component and the second adjustment component move relative to each other, the traction cable drives the temperature detection device connected thereto to change the axial position relative to the electrode 1;

[0287] The first bending component 4 and the first adjusting component are configured separately or are the same component.

[0288] The second adjusting component and the second stretching and bending component move independently relative to the first stretching and bending component, and the movement forms of the second adjusting component and the second stretching and bending component are also independent of each other, for example, one is sliding and the other is rotating.

[0289] If the temperature detection device also needs to be adjusted in the body, in order to obtain the position of the temperature detection device relative to the electrode, the proximal calibration traction cable movement distance can be used, or the temperature detection device itself is used as a developing material, and the position of the temperature detection device relative to the electrode is calculated through imaging.

[0290] In one of the embodiments, a pressure sensor 17 for detecting changes in contact pressure between the electrode 1 and the ablated tissue is further disposed in the electrode 1 .

[0291] The pressure sensor 17 is preferably welded and fixed inside the electrode 1 and connected to the ablation device connector 7. When the electrode 1 contacts the ablation tissue and cannot move further, the pressure sensor 17 senses the pressure change at the electrode 1 and transmits it to the ablation device. Under the guidance of bronchial navigation, the pressure sensor 17 passes through the forceps channel of the bronchoscope and enters the ablation tissue through the hole punctured in the bronchial wall near the lesion in advance, thereby more effectively judging the exact position of the electrode 1 and improving the positioning accuracy of the electrode 1.

[0292] Combination Figure 8In order to install thermistor 9, pull wire 10, pressure sensor 17 and wire 16, the end of electrode 1 facing the installation direction of sheath tube 2 is provided with first installation hole 102, second installation hole 103, third installation hole 104 and fourth installation hole 105, and thermistor 9, pull wire 10, pressure sensor 17 and wire 16 are installed in the four installation holes respectively. In addition, a fifth installation hole can be further provided for connecting the traction rope. When there are multiple traction ropes, a corresponding number of installation holes are provided.

[0293] Based on the above embodiments, some embodiments of the present application further provide a radiofrequency ablation method, including:

[0294] Step S100, obtaining temperature information during ablation;

[0295] Step S110, comparing the temperature information with the temperature threshold;

[0296] Step S120: When the temperature information and the temperature threshold meet the set relationship, a stop ablation instruction is sent.

[0297] The process and specific steps of the radiofrequency ablation method can also refer to the relevant description in the following radiofrequency ablation control method.

[0298] Similarly, based on the above embodiments, some embodiments of the present application also provide a temperature monitoring method for radiofrequency ablation, including:

[0299] Step S100, obtaining temperature information during ablation;

[0300] Step S110, comparing the temperature information with the temperature threshold;

[0301] Step S120: When the temperature information and the temperature threshold meet the set relationship, a stop ablation instruction is sent.

[0302] Similarly, based on the above embodiments, some embodiments of the present application also provide a method for controlling radiofrequency ablation, including:

[0303] Step S100, obtaining temperature information during ablation;

[0304] Step S110, comparing the temperature information with the temperature threshold;

[0305] Step S120: When the temperature information and the temperature threshold meet the set relationship, a stop ablation instruction is sent.

[0306] Before step S100, first position the end of the radiofrequency ablation catheter near the tumor cells or diseased cells, puncture into the cells, and generally make the distal end of the electrode correspond to the center of the lesion site. Then, the electrode is energized to start ablation. The temperature information obtained in real time can be collected in real time by means of the aforementioned thermistor 9 or temperature detection device (hereinafter also collectively referred to as the temperature detection device), etc. The specific collection method can also be implemented in combination with other existing technologies.

[0307] The temperature information has a corresponding detection site in space, that is, the position where the temperature detection device is located. Although there are also means or methods for obtaining temperature information in the prior art, most are limited to the position of the electrode.

[0308] In one embodiment, the temperature information includes edge temperature information, and the distance between the detection site corresponding to the edge temperature information and the distal end of the electrode is L; and L0≤L is satisfied, where L0 is the predicted radius of the lesion site;

[0309] The set relationship includes that the edge temperature information reaches the temperature threshold and maintains a preset time interval.

[0310] Conventional ablation operations generally preset the ablation time and stop ablation after the time is reached, but the ablation effect cannot be guaranteed. In this embodiment, determining the ablation endpoint by the temperature change at a specified position in the temperature field can further ensure the ablation effect.

[0311] In one embodiment, the temperature information further includes first temperature information, and the distance between the detection site corresponding to the first temperature information and the distal end of the electrode is L1; and L1<L0 is satisfied, where L0 is the predicted radius of the lesion site.

[0312] In one embodiment, the set relationship further includes that the first temperature information reaches 60-100 degrees.

[0313] The detection site corresponding to the first temperature information is inside the lesion site. By monitoring the change of the first temperature information, the ablation process inside the lesion site can be reflected. For example, it can be judged whether it is near the ablation endpoint.

[0314] In one embodiment, the edge temperature information includes third temperature information, and the distance between the detection site corresponding to the third temperature information and the distal end of the electrode is L3; and L0<L3 is satisfied, where L0 is the predicted radius of the lesion site.

[0315] In the prior art, during ablation, the radiofrequency ablation catheter is directly inserted into the lesion site (lesioned tissue mass) under the guidance of B-ultrasound or CT. When the electrodes in the radiofrequency ablation catheter are energized, the temperature in the tissue can exceed 60°C, causing cell death and a necrotic area. If the local tissue temperature exceeds 100°C, coagulation necrosis will occur in the tumor tissue and the substance of the surrounding organs. During treatment, a large spherical coagulation necrosis area can be produced. Outside the coagulation necrosis area, there is a thermal therapy area of ​​43 to 60°C. In this area, cancer cells can be killed and normal cells can recover.

[0316] In one of the embodiments, the setting relationship is that the third temperature information reaches the temperature threshold and maintains a preset time interval; the temperature threshold is 43-60°C, and the time interval is not less than 3 minutes.

[0317] To ensure the ablation effect, for example, the temperature threshold corresponding to the third temperature information may be set to be close to or equal to 60°C, such as 55-60°C.

[0318] If the third temperature information is 43-60° C., it means that the outer edge of the lesion has reached this temperature. When this temperature is reached, a stop ablation instruction can be sent immediately or after a predetermined delay.

[0319] In one embodiment, the edge temperature information also includes second temperature information, and the distance between the detection site corresponding to the second temperature information and the distal end of the electrode is L2; ​​and L2=L0 is satisfied, where L0 is the predicted radius of the lesion site.

[0320] In one of the embodiments, the setting relationship further includes the second temperature information reaching 60-90 degrees.

[0321] The detection part corresponding to the second temperature information is roughly the same as the radius of the lesion part, so the temperature condition of the outer edge of the lesion part can be accurately known, which is beneficial to the precise monitoring of temperature.

[0322] In one embodiment, the temperature information further includes distal temperature information, and the detection portion corresponding to the distal temperature information is the distal end of the electrode.

[0323] In one of the embodiments, the setting relationship also includes the remote temperature information reaching 60-100 degrees.

[0324] In one embodiment, the temperature information includes:

[0325] Remote temperature information, the detection location corresponding to the remote temperature information is the remote end of the electrode;

[0326] first temperature information, where the distance between the detection position corresponding to the first temperature information and the distal end of the electrode is L1;

[0327] The second temperature information, the distance between the detection site corresponding to the second temperature information and the distal end of the electrode is L2;

[0328] The third temperature information, the distance between the detection site corresponding to the third temperature information and the distal end of the electrode is L3;

[0329] And it satisfies L1 < L0 = L2 < L3, where L0 is the predicted radius of the lesion site.

[0330] Collecting the temperatures corresponding to multiple sites can monitor the temperature field near the electrode and around the lesion during the ablation process. When the distal end of the electrode corresponds to the center position of the lesion, the peripheral temperature distribution with the center of the lesion as the origin can be obtained. According to the change of the temperature gradient, the ablation process can be indicated. The radius of the lesion site can be pre-measured by imaging equipment and other means, and the approximate radius range can be calculated. By detecting the temperatures of multiple sites, the progress of the ablation can be accurately known, further ensuring the ablation effect.

[0331] In one embodiment, it further includes visualizing and displaying the temperature distribution around the electrode according to the temperature information during the ablation process.

[0332] During the visualization process, the change of the temperature field centered on the distal end of the electrode can be simulated and displayed through various types of icons or three-dimensional shapes.

[0333] See Fig.19 , let point M be the distal end of electrode 1. During the ablation process, point M is the body center of the lesion site;

[0334] Point M is the distal end of the electrode, and the temperature information collected from point M is the distal temperature information;

[0335] The distance between point X1 and point M is L1, and the temperature information collected from point X1 is the first temperature information;

[0336] The distance between point X2 and point M is L2, and the temperature information collected from point X2 is the second temperature information;

[0337] The radius L0 of the lesion site = L2;

[0338] The distance between point X3 and point M is L3, and the temperature information collected from point X3 is the third temperature information;

[0339] During the ablation process, according to the changes of each temperature information, the temperature field schematic diagram as shown in Fig.19 can be drawn and displayed. Different cross-hatched areas mean different temperatures. When actually displayed, different colors and other methods can be used for distinction. And according to the change of the temperature, the display color is correspondingly changed, for example, the color gradually deepens as the temperature rises or changes from a cold color to a warm color, etc.

[0340] When judging the ablation progress in combination with the temperature field diagram, for example:

[0341] When the first temperature information reaches the temperature threshold, but the second temperature information does not reach the temperature threshold, it can be determined that ablation is in progress;

[0342] When the second temperature information reaches the temperature threshold, but the third temperature information does not reach the temperature threshold, it can be determined that the ablation is about to be completed;

[0343] When the third temperature information reaches the temperature threshold and can be maintained for a certain period of time (usually 3 minutes), it can be determined that the ablation is completed.

[0344] Since the detection site corresponding to the third temperature information is located in the peripheral area of ​​the lesion, the ablation effect can be ensured by monitoring the ablation endpoint through the third temperature information.

[0345] In one embodiment, the radiofrequency ablation catheter of the above embodiment is used during radiofrequency ablation, and the first temperature information, the second temperature information and the third temperature information are respectively collected from the first temperature detection device, the second temperature detection device and the third temperature detection device. The distal temperature information is collected from the temperature detection probe installed at the distal end of the electrode.

[0346] The radiofrequency ablation catheter of the aforementioned embodiment is equipped with a temperature detection probe, a first temperature detection device, a second temperature detection device and a third temperature detection device.

[0347] The temperature detection probe is installed at the distal end of the electrode, and the positions of the other three temperature detection devices are arranged in sequence from the distal end to the proximal end, and the distances between the three and the distal end of the electrode correspond to L1, L2, and L3 respectively.

[0348] Since L0 is different in different situations, the positions of the three temperature detection devices can be adjusted in advance as needed to meet L1 <L0=L2<L3。

[0349] For example, considering the size of lung tumor cells or diseased cells (generally about one centimeter in radius), and of course taking into account the temperature conduction of the internal body environment, L3 can be selected as 1.5 cm and L1 can be selected as half of L0 (0.5 cm).

[0350] After a period of ablation operation, if the temperature information still does not reach the temperature threshold, the position of the electrode is adjusted and a second ablation instruction is issued. The position of the electrode can be adjusted according to the wire pulling method of the aforementioned related embodiments, or the radiofrequency ablation catheter can be directly advanced or retracted as a whole until the temperature information reaches the temperature threshold to end the ablation operation.

[0351] In each embodiment of the present application, each step in the method flow is not necessarily performed in sequence according to the order of narration or drawings. Unless there is a clear explanation in this article, the execution of these steps does not have strict order restrictions, and these steps can be performed in other orders. Moreover, at least a portion of the steps may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily performed in sequence, but can be performed in turn or alternately with at least a part of other steps or sub-steps or stages of other steps.

[0352] One of the embodiments of the present application further provides a lung radiofrequency ablation system, in which the radiofrequency ablation catheters of the above embodiments can and preferably are used. When the radiofrequency ablation catheters of the above embodiments are used, the relevant structural features and method processes can be referred to the above embodiments, and will not be repeated in this embodiment.

[0353] A pulmonary radiofrequency ablation system, comprising:

[0354] Radiofrequency ablation catheter (the radiofrequency ablation catheter in the above embodiments may be used);

[0355] A heat exchange medium delivery device for providing heat exchange medium to the peripheral area of ​​the electrode of the radiofrequency ablation catheter;

[0356] The control module of the heat exchange medium conveying device is driven accordingly according to the impedance information of the loop where the electrode in the radiofrequency ablation catheter is located.

[0357] When the electrode of the radiofrequency ablation catheter is powered on, the surrounding temperature rises. In order to prevent the surrounding tissue from drying and carbonizing, a heat exchange medium can be used for protection. The real-time output of the heat exchange medium can be regulated according to the change of the electrode loop impedance information. When the electrode is working, a loop is formed. The measurement and calculation of the impedance in the loop can be implemented using existing technology.

[0358] If the electrode drive signal (such as the applied voltage signal) is controlled only according to the temperature, there will generally be a lag in signal feedback, because the conduction of temperature is related to the internal environment and the thermal conductivity of related components. In this embodiment, a corresponding control logic association is established between the output of the heat exchange medium and the impedance information. The impedance information is a more direct electrical signal, which is conducive to real-time monitoring and avoids lag.

[0359] Since the impedance information feedback is more timely, the stable output of the electrode can be maintained, that is, there is no need to frequently adjust the electrode drive signal according to the temperature of the lesion site, and the ablation process is stable and easy to control.

[0360] In one preferred embodiment, the electrode driving signal is kept unchanged during the ablation process.

[0361] The electrode driving signal comes from the ablation device and is transmitted to the electrode through the circuit. Conventional technology can be used for the electrode driving signal itself, which is not the focus of improvement of this application.

[0362] In one embodiment, the lung radiofrequency ablation system further includes a temperature detection device for collecting temperature information of the electrode peripheral area, and the control module is further used to prompt or control the ablation process according to the temperature information.

[0363] The temperature of the electrode surrounding area reflects the ablation process to a certain extent. For example, when the lesion is at a certain temperature, it can be inactivated after being heated for a period of time. At this time, the control module can output a prompt instruction, or output a stop ablation instruction to stop the electrode from working. For another example, when the temperature is too high, it may be that the heat exchange medium output is abnormal. The control module can output a prompt instruction to alarm.

[0364] In one embodiment, there are one or more temperature detection devices, and the location of at least one temperature detection device (i.e., the point where the temperature information is collected) is 0.5 to 3 cm away from the electrode, preferably 1 to 2 cm, such as 1.5 cm.

[0365] In combination with the aforementioned related embodiments, since the electrode is generally located in the central area of ​​the lesion when in use, at least one temperature information collection point should be at a certain distance from the electrode to reflect the ablation process in a space with the distance as the radius.

[0366] The electrode periphery is in the three-dimensional space centered on the electrode, but the impedance sensor and the temperature detection device themselves can be configured separately. The preferred method is to integrate them into the radiofrequency ablation catheter to maintain their relative position with the electrode.

[0367] In one embodiment, the control module drives the heat exchange medium delivery device to adjust the heat exchange medium flow rate. The heat exchange medium delivery device may include conventional fluid delivery devices such as containers, pipelines, pumps, valves, flow meters, etc., wherein at least the device can adjust the delivery amount of the heat exchange medium, such as a controlled valve or pump, etc. The control module adjusts the delivery amount of the heat exchange medium through corresponding control instructions. After the heat exchange medium flow rate changes, the collected impedance information also changes accordingly.

[0368] In order to maintain a stable ablation process, in one embodiment, the control module compares the impedance information with a threshold value, and makes the impedance information approach a steady-state impedance by adjusting the flow rate of the heat exchange medium.

[0369] In order to make the impedance information approach the threshold, the two are continuously compared at a certain sampling period during operation, and the heat exchange medium flow is adjusted accordingly according to the size relationship between the two to achieve closed-loop control.

[0370] The threshold may be a numerical point or a numerical range. When it is a numerical range, the impedance information is compared with the upper and lower limits of the numerical range to ensure that the impedance information is within the numerical range.

[0371] Since the in vivo environments or lesion sites of different patients are not the same, in one embodiment, the steady-state impedance is calibrated in the initial stage, and the threshold is calculated based on the steady-state impedance.

[0372] The impedance information may be an impedance value or other parameters related to the impedance value, and the threshold value is in the form corresponding to it for mutual comparison. For example, if the impedance value is higher than the threshold value, it means that the heat exchange medium flow rate needs to be increased to further improve the wetting or cooling effect, and vice versa.

[0373] In one embodiment, the steady-state impedance is calibrated in such a way that after the radiofrequency ablation catheter is in place in the body and before the electrode is energized, the heat exchange medium is output at an initial flow rate and impedance information is collected in real time. When the impedance information is stable, the corresponding value is recorded as the steady-state impedance.

[0374] After the radiofrequency ablation catheter is in place in the body, the initial flow rate of the initial heat exchange medium (for example, 0.5 ml / min) can be determined based on experience or historical data. During this stage, the impedance information will fluctuate due to the infusion of the heat exchange medium. For example, the infusion of physiological saline may cause the impedance information to decrease. The impedance information is collected in real time. When the impedance information no longer decreases and remains stable, the impedance information at this time is the steady-state impedance.

[0375] When the threshold is a numerical range, the upper and lower limits of the threshold are the upper impedance and the lower impedance, respectively. The upper impedance and the lower impedance can be calculated in combination with the steady-state impedance, or even the steady-state impedance itself, for example, the lower impedance can also use the steady-state impedance itself. The specific calculation method of the upper impedance and the lower impedance can be determined according to empirical data or the patient's personal situation.

[0376] In one embodiment, the threshold is a numerical range; during the process of adjusting the heat exchange medium flow, the control module also collects impedance information in real time and determines the impedance information change trend, and changes the adjustment amplitude of the heat exchange medium flow accordingly according to the impedance information change trend or selects one of the upper threshold value and the lower threshold value for comparison.

[0377] The heat exchange medium flow rate is generally adjusted according to a certain step interval. Maintaining the current flow rate or further changing the flow rate can be determined by the impedance information change trend. The impedance information change trend can be rising or falling. For example, when increasing the heat exchange medium flow rate, the expected purpose is to reduce the impedance information. If the impedance information change trend is still rising, the heat exchange medium flow rate can be further increased, that is, relative to the initial flow rate of the heat exchange medium, the adjustment range is further increased.

[0378] If the impedance information change trend is downward, it means that it has met expectations. At this time, the collected impedance information can be directly compared with the lower threshold to determine whether the heat exchange medium flow needs to be reduced.

[0379] See also Fig.21 Based on the aforementioned lung radiofrequency ablation system, in one embodiment, a lung radiofrequency ablation method is further provided, comprising:

[0380] Step S500, receiving impedance information collected from the electrode loop during the ablation process;

[0381] Step S510: Generate corresponding control instructions according to the impedance information to adjust the flow rate of the heat exchange medium around the electrode.

[0382] For the specific process and details of the pulmonary radiofrequency ablation method, please refer to the description of the control method of pulmonary radiofrequency ablation.

[0383] See also Fig.21 Based on the aforementioned pulmonary radiofrequency ablation system, in one embodiment, a method for impedance monitoring of pulmonary radiofrequency ablation is further provided, comprising:

[0384] Step S500, receiving impedance information collected from the electrode loop during the ablation process;

[0385] Step S510: Generate corresponding control instructions according to the impedance information to adjust the flow rate of the heat exchange medium around the electrode.

[0386] See also Fig.21 Based on the aforementioned pulmonary radiofrequency ablation system, in one embodiment, a control method for pulmonary radiofrequency ablation is further provided, comprising:

[0387] Step S500, receiving impedance information collected from the electrode loop during the ablation process;

[0388] Step S510: Generate corresponding control instructions according to the impedance information to adjust the flow rate of the heat exchange medium around the electrode.

[0389] The implementation of ablation, collection of impedance information, and output of heat exchange medium can all be combined with the radiofrequency ablation catheter or related equipment and systems in the previous embodiments, and the relevant specific structures will not be repeated.

[0390] In one embodiment, step S500 further includes pre-calibrating a steady-state impedance, and calculating a threshold value based on the steady-state impedance. The threshold value is used to compare with the impedance information in step S510 to generate a corresponding control instruction.

[0391] In one embodiment, the steady-state impedance is calibrated in such a way that after the radiofrequency ablation catheter is in place in the body and before the electrode is energized, the heat exchange medium is output at an initial flow rate and impedance information is collected in real time. When the impedance information is stable, the corresponding value is recorded as the steady-state impedance.

[0392] In step S510, a corresponding control instruction is generated according to the impedance information, specifically including:

[0393] Step S511, comparing the impedance information with a threshold, and determining the increase or decrease of flow rate according to the relationship between the impedance information and the threshold;

[0394] Step S512, generating corresponding control instructions according to the increase or decrease of the flow rate and the predetermined increase or decrease range.

[0395] Determining the increase or decrease of flow is understood as the expected flow change or demand, such as further increasing the flow on the basis of the current flow, or further reducing the flow on the basis of the current flow, and the increase or decrease can be preset in step.

[0396] For example, if the current flow rate is X ml / s, when the flow rate is further increased, a control instruction is sent to the heat exchange medium conveying device to change the flow rate to X+Y ml / s, and Y can be regarded as an increase. The same applies when the flow rate needs to be further reduced.

[0397] In one embodiment, the increase and decrease amplitudes are independently fixed values ​​or dynamic values.

[0398] The increase or decrease can be a fixed value or set to a dynamic value, for example, related to the current impedance information, or the difference between the impedance information and the threshold is set to Z, and the increase or decrease is a dynamic value and related to Z. For example, the closer the current impedance information is to the threshold, the smaller the increase or decrease, so that the control is more precise and the feedback lag is minimized.

[0399] The relationship between the impedance information and the threshold value can be a simple comparison of numerical values ​​or can conform to other functional relationships. This is related to the specific physical parameters, variation forms and even measurement units of the impedance information and the threshold value.

[0400] In one embodiment, the impedance information and the threshold are both impedance values, in ohms. This facilitates comparison.

[0401] The threshold is a numerical range. In step S511, the increase or decrease of the flow rate is determined according to the relationship between the impedance information and the threshold, which specifically includes:

[0402] When the impedance information is greater than the upper threshold value, it is determined to increase the flow rate;

[0403] When the impedance information is less than the lower limit of the threshold, it is determined to reduce the flow rate;

[0404] When the impedance information is within the threshold range, the current flow rate is maintained;

[0405] In step S511, when it is determined that the flow rate is to be increased, a first control instruction is generated in step S512, and the heat exchange medium flow rate corresponding to the first control instruction is greater than the current flow rate;

[0406] In step S511, when it is determined that the flow rate is to be reduced, a second control instruction is generated in step S512, and the heat exchange medium flow rate corresponding to the second control instruction is less than the current flow rate.

[0407] The control instruction itself can directly change the pump speed, valve opening, etc. as an electrical signal. The actions of these controlled devices also correspond to the changes in the heat exchange medium flow rate. Therefore, the form of the control instruction itself is not strictly limited, but at least it can correspond to the flow rate changes of the heat exchange medium flow rate.

[0408] The acquisition of impedance information is real-time, which can also be understood as following a predetermined sampling period and continuously comparing with a threshold value, and these operations are performed throughout the ablation process, that is, the operation steps S500 and S510 are repeated.

[0409] In one embodiment, step S500 and step S510 are executed cyclically according to the sampling period of the impedance information;

[0410] After the control instruction is generated and output in the previous sampling cycle, in the next cycle, after the impedance information is collected, before it is compared with the threshold, it is first compared with the impedance information of the previous sampling cycle to determine the change trend of the impedance information;

[0411] According to the variation trend of the impedance information, the adjustment amplitude of the heat exchange medium flow rate is changed accordingly or one of the upper threshold value and the lower threshold value is selected for comparison.

[0412] The control instruction of the previous sampling cycle may be the first control instruction or the second control instruction. Then different types of control instructions can select different judgment methods in the next cycle, for example:

[0413] In one embodiment, after the first control instruction is generated and output in the previous sampling cycle, in the next cycle, the impedance information is compared with the impedance information of the previous sampling cycle before being compared with the threshold value to determine the change trend of the impedance information;

[0414] When the impedance information shows an upward trend, the adjustment range of the heat exchange medium flow rate is increased;

[0415] When the impedance information has a decreasing trend, the impedance information of the current sampling period is compared with the lower threshold.

[0416] For another example: in one embodiment, after the second control instruction is generated and output in the previous sampling cycle, in the next cycle, the impedance information is compared with the impedance information of the previous sampling cycle before being compared with the threshold value to determine the change trend of the impedance information;

[0417] When the impedance information shows a downward trend, the adjustment range of the heat exchange medium flow rate is increased;

[0418] When the impedance information has an increasing trend, the impedance information of the current sampling period is compared with the upper threshold value.

[0419] The ablation process may end at a preset time or according to the temperature of the electrode or lesion. In one embodiment, the ablation process may be prompted or controlled by the radiofrequency ablation method, control method or impedance monitoring method in the aforementioned embodiments.

[0420] For example, while monitoring impedance information in real time, the following can also be performed:

[0421] Step S100, obtaining temperature information during ablation;

[0422] Step S110, comparing the temperature information with the temperature threshold;

[0423] Step S120: When the temperature information and the temperature threshold meet the set relationship, send a stop ablation instruction. The specific steps of temperature monitoring can be combined with the above-mentioned related embodiments.

[0424] In this embodiment, during the ablation process, temperature information collected from the peripheral area of ​​the electrode is received in real time, and the ablation process is prompted or controlled based on the temperature information.

[0425] The temperature of the electrode surrounding area reflects the ablation process to a certain extent. For example, when the lesion is at a certain temperature, it can be inactivated after being heated for a period of time. At this time, the control module can output a prompt instruction, or output a stop ablation instruction to stop the electrode from working. For another example, when the temperature is too high, it may be that the heat exchange medium output is abnormal. The control module can output a prompt instruction to alarm.

[0426] In one embodiment, the temperature information collection point is 0.5 to 3 cm away from the electrode; after the temperature information reaches 43 to 60° C. and maintains for a preset time, a stop ablation instruction is sent.

[0427] The command to stop ablation can be to directly disconnect the electrode power supply or to give a prompt message. The temperature information can be used to prompt or control the ablation process. Logically, there is no connection with using impedance information to control the flow of heat exchange medium. Using impedance information to control the flow of heat exchange medium focuses on the regulation of the ablation process, while using temperature information to prompt or control the ablation process only intervenes at important process nodes, such as by disconnecting the circuit or prompting to jump out when cyclically executing steps S500 and S510.

[0428] See also Fig. 20 In one embodiment, a process of a pulmonary radiofrequency ablation method or control method includes first perfusing a heat exchange medium at an initial flow rate, and the heat exchange medium flows out through a cleansing cover outside the electrode to form a protective film. At this time, impedance changes are collected and monitored. When the impedance is stable, the current impedance is the steady-state impedance.

[0429] The electrode is energized to start ablation, and impedance information is collected in real time. The impedance information obtained is continuously compared with a threshold value and a corresponding control instruction is generated to adjust the flow of the heat exchange medium, wherein the threshold value is a range, wherein the lower limit impedance can adopt a steady-state impedance.

[0430] As ablation proceeds, the impedance increases. When the impedance information is greater than the set upper limit impedance, a first control instruction is generated and sent, i.e., increasing the flow rate of the heat exchange medium.

[0431] The impedance information of the next sampling period is then compared with the impedance information of the previous sampling period to determine whether the impedance is rising. If it is still rising, the first control instruction is generated and sent again, that is, the flow rate of the heat exchange medium is further increased;

[0432] If the impedance stops rising and starts to fall, then when the impedance information is less than the set lower limit impedance compared to the lower limit impedance, a second control instruction is generated and sent, i.e., reducing the heat exchange medium flow rate;

[0433] The impedance information of the next sampling cycle is then compared with the impedance information of the previous sampling cycle to determine whether the impedance has decreased. If it is still decreasing, a second control instruction is generated and sent again, that is, the heat exchange medium flow rate is further reduced until the impedance starts to increase.

[0434] Based on the above cycle, the impedance information is continuously monitored during the ablation process, and the flow rate of the heat exchange medium is adjusted. When the preset conditions are met, such as calculating the time or monitoring the temperature, the ablation is prompted or terminated.

[0435] The various steps in the above-mentioned pulmonary radiofrequency ablation method and the control method of pulmonary radiofrequency ablation are not necessarily performed in the order of the description or the drawings. Unless otherwise clearly stated in this document, there is no strict order restriction for the execution of these steps, and these steps can be performed in other orders. Moreover, at least a part of the steps may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be performed in turn or alternately with other steps or at least a part of the sub-steps or stages of other steps.

[0436] Based on the above-mentioned lung radiofrequency ablation method, this embodiment provides a lung radiofrequency ablation device, including:

[0437] An acquisition module, used for receiving impedance information collected from the electrode loop during the ablation process;

[0438] The regulating module is used to generate corresponding control instructions according to the impedance information to regulate the flow of heat exchange medium around the electrode.

[0439] Similarly, based on the aforementioned impedance monitoring method for pulmonary radiofrequency ablation, this embodiment provides an impedance monitoring device for pulmonary radiofrequency ablation, including:

[0440] An acquisition module, used for receiving impedance information collected from the electrode loop during the ablation process;

[0441] The regulating module is used to generate corresponding control instructions according to the impedance information to regulate the flow of heat exchange medium around the electrode.

[0442] Similarly, based on the aforementioned control method for pulmonary radiofrequency ablation, this embodiment provides a control device for pulmonary radiofrequency ablation, including:

[0443] An acquisition module, used for receiving impedance information collected from the electrode loop during the ablation process;

[0444] The regulating module is used to generate corresponding control instructions according to the impedance information to regulate the flow of heat exchange medium around the electrode.

[0445] The specific limitations and related details of the pulmonary radiofrequency ablation device, as well as the control device and impedance monitoring device of the pulmonary radiofrequency ablation in this embodiment can be found in the above-mentioned limitations on the pulmonary radiofrequency ablation method, the control method and impedance monitoring method of the pulmonary radiofrequency ablation, and will not be repeated here. Each module in the above-mentioned pulmonary radiofrequency ablation device and the control device for pulmonary radiofrequency ablation can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above-mentioned modules.

[0446] In one embodiment of the present application, a lung radiofrequency ablation system is also provided, which is combined with Fig.21 In this embodiment, the lung radiofrequency ablation system includes a radiofrequency signal generator 100, an ablation catheter 110, an electrode plate, a sensor module 120, a micro-infusion pump 130, a control module 140 and an alarm module 150.

[0447] In this embodiment, the RF signal generator 100 may adopt the aforementioned ablation device (or be a part of the ablation device); the ablation catheter 110 may adopt the RF ablation catheter in the aforementioned embodiments; the heat exchange medium specifically takes physiological saline as an example, and the heat exchange medium flow channel is a transmission channel for liquid transmission; the micro-infusion pump 130 can be understood as a form or one of the devices of the heat exchange medium delivery device; the control module 140 may adopt the RF ablation device in the aforementioned embodiments.

[0448] In addition, the control module 140, the alarm module 150, and the micro-infusion pump 130 may be partially or fully integrated in terms of spatial arrangement, for example, integrated into the ablation device to form an ablation device.

[0449] In this embodiment, the RF signal generator 100 is connected to the control module 140 , and is used to receive a command from the control module 140 to generate a RF signal, and transmit the RF signal to the ablation catheter 110 .

[0450] In this embodiment, the ablation catheter 110 has an electrical transmission channel for electrical transmission and a transmission channel for liquid transmission. The radio frequency signal generator 100 is connected to the electrical transmission channel, and the liquid transmission channel is connected to the micro-infusion pump 130 .

[0451] The ablation catheter 110 can receive the radio frequency signal generated by the radio frequency signal generator 100 and apply the radio frequency signal to the ablated tissue when piercing the ablated tissue. It can also receive the physiological saline injected by the micro-infusion pump 130. The front end of the ablation catheter 110 (the end extending into the human body) is provided with a liquid outlet hole for injecting physiological saline into the ablated tissue when piercing the ablation tissue.

[0452] In the aforementioned related embodiments, the electrode 1 is covered with a wetting cover 20 , and a plurality of wetting holes 200 are evenly arranged on the wetting cover 20 . When the wetting cover 20 is provided, the liquid outlet holes mentioned in this embodiment can also be understood as the wetting holes 200 .

[0453] In other embodiments, the ablation catheter 110 may be provided with other structures, as long as the effect of injecting saline into the ablated tissue is achieved. For example, the ablation catheter 110 has a bendable structure, and the bendable structure can be controlled to bend the front end of the ablation catheter 110 so as to accurately deliver the front end of the ablation catheter 110 to the treatment site; and / or, an operating unit for controlling the bendable structure may be provided on the outside of the ablation catheter, so that medical personnel can operate to control the degree of bendability of the bendable structure.

[0454] Specifically, under the guidance of B-ultrasound or CT, the ablation catheter 110 punctures into the ablation tissue through the puncture point via a bronchoscope, and transmits the radio frequency signal to the ablation tissue. At this time, the electrode plate connected to the radio frequency signal generator 100 and attached to the patient's body is connected to the ablation catheter 110 to form an electric field. The ablation tissue is also in the electric field. The high-frequency current acts on the human tissue between the two, causing the tumor cells contacted by the electrode at the far end of the radio frequency ablation catheter to coagulate, degenerate, and necrotize. Among them, the ablation catheter 110 is only an electrode for transmitting energy. The increase in its temperature is caused by the high-speed oscillation and mutual friction of ions in the tumor tissue near the ablation catheter 110 after the loop is formed, and the radio frequency energy is converted into heat energy. In other words, the ablation catheter 110 is passively heated due to the heating of the nearby tissue. After the tissue is electrified, it will dry and carbonize, forming a "scab" around the ablation catheter 110, "vacuum-wrapping" the ablation catheter 110, and the impedance between the ablation catheter 110 and the "scab" tissue will instantly become very large (i.e., the effects of heat sink and high impedance during radiofrequency ablation), which will cause the ablation to stop, resulting in incomplete ablation and insufficient ablation range. In this embodiment, the ablation catheter 110 is provided with a liquid outlet to inject saline into the ablation tissue. Since saline is a conductor, after infiltrating the ablation tissue, the impedance can be ensured to be stable within a certain range during the entire ablation process, so that the radiofrequency energy can be continuously output, thereby forming a sufficiently large ablation range and producing a larger and more effective coagulation necrosis focus.

[0455] In this embodiment, the sensor module 120 is disposed on the ablation catheter 110, and the sensor module 120 is connected to the control module 140. Specifically, the sensor module 120 is disposed at the end of the ablation catheter 110 that contacts the ablation tissue. The sensor module 120 includes an impedance sensor and a temperature sensor, which are used to detect the impedance and temperature of the contact position between the ablation catheter 110 and the ablation tissue and send the temperature information and impedance information to the control module 140; specifically, the temperature sensor can be a thermocouple.

[0456] The temperature sensor may also be the thermistor 9, electrode ring 8 or temperature detection device configured on the radiofrequency ablation catheter in the above embodiments. The impedance sensor may be understood as a sampling circuit or the like, which is used to obtain the impedance information of the electrode loop.

[0457] In this embodiment, the impedance information is acquired by the impedance sensor and transmitted to the control module 140. In other embodiments, the impedance information can be calculated based on the voltage and current values ​​collected by the system. Specifically, the real-time voltage and current values ​​are measured by the voltage and current measuring device and transmitted to the control module 140. The control module 140 calculates the impedance based on the real-time voltage and current values. In other embodiments, the sensor module 120 may also include other types of sensors such as flow sensors and pressure sensors to detect the flow of physiological saline and other data such as the pressure at the contact position between the ablation catheter 110 and the ablation tissue to monitor the ablation situation and to handle abnormalities in a timely manner. For example, when the flow information of the physiological saline transmitted by the flow sensor is lower than a certain threshold, the control module 140 controls the micro-infusion pump 130 to increase the infusion volume of physiological saline to avoid "scab" of human tissue. In other embodiments, the sensor type and quantity of the sensor module can be set according to the needs and actual conditions when the pulmonary radiofrequency ablation system is working to monitor the ablation situation.

[0458] In this embodiment, the micro perfusion pump 130 is connected to the control module 140 and the ablation catheter 110, and is used to receive a command from the control module 140 to perfuse physiological saline into the ablation catheter 110. In other embodiments, the micro perfusion pump 130 can receive a command from the control module 140 to perfuse other liquids into the ablation catheter 110, and it is only necessary to improve the electrical conductivity and thermal conductivity of the ablated tissue, maintain impedance balance, keep the impedance in a relatively stable state, reduce the temperature of the ablated tissue, increase the humidity of the ablated tissue, and fundamentally avoid the effect of ablation tissue scabbing due to drying and heating, and not to cause serious side effects to the human body.

[0459] In this embodiment, the alarm module 150 is connected to the control module 140 and is used to receive an alarm command issued by the control module 140 and generate an alarm.

[0460] In this embodiment, the control module 140 is connected to the RF signal generator 100, the sensor module 120, the micro-infusion pump 130, and the alarm module 150. Specifically, the control module 140 is used to control the RF signal generator 100 to generate RF signals. Specifically, the control module 140 receives the impedance information and temperature information detected by the sensor module 120, and controls the micro-infusion pump 130 to infuse saline into the ablation catheter 110 based on the impedance information. In this embodiment, if the impedance sensor detects a sharp increase in impedance, it means that the tissue near the electrode of the ablation catheter 110 is drying and carbonizing, and scabs will form. After receiving the impedance information from the impedance sensor, the control module 140 controls the micro-infusion pump 130 to increase the infusion amount of saline. In this embodiment, the control module 140 is also used to determine whether the infusion of saline is unobstructed based on the temperature information, and issue an alarm command if it is not unobstructed. Specifically, if the temperature rises above a certain threshold (eg, 85 degrees) during the ablation process, the control module 140 determines that the perfusion of physiological saline is blocked, issues an alarm command, and controls the alarm module 150 to issue an alarm signal to ensure smooth ablation.

[0461] The alarm about the limit situation during the ablation process can be obtained through temperature monitoring or impedance information monitoring, or a combination of the two. As long as one exceeds the acceptable upper limit, an alarm will be issued or ablation will be stopped.

[0462] In other embodiments, when the sensor module 120 also includes other types of sensors such as flow sensors and pressure sensors, the control module 140 also receives other data information sent by the sensor module 120 to monitor the ablation situation, and sends control commands in time for processing when an abnormality occurs. In other embodiments, the control module 140 can make a comprehensive judgment on the ablation situation based on the data transmitted by multiple sensors, and control the micro-infusion pump 130, the radio frequency signal generator 100 and other equipment to adjust when the preset conditions are met to ensure the smooth progress of the ablation process. The preset conditions can be set by the user according to the actual situation when the lung radiofrequency ablation system is working and the setting of the sensor. In other embodiments, the impedance information can be calculated based on the voltage and current values ​​collected by the system. Specifically, the real-time voltage and current values ​​are measured by the voltage and current measuring equipment and transmitted to the control module 140, and the control module 140 calculates the impedance based on the real-time voltage and current values.

[0463] The electrode plate is connected to the radio frequency signal generator and is used to form a loop with the electrode in the ablation catheter through the human body.

[0464] The electrode plate is attached to the appropriate part of the patient's body. During the ablation operation, the electrode in the ablation catheter forms a working circuit (i.e. the aforementioned circuit where the electrode is located) through the human body and the electrode plate. The high-frequency current acts on the human tissue between the two, causing the lesion site contacted by the electrode to coagulate, degenerate, and necrotize. The electrode plate itself is a conventional component of the ablation operation and is omitted in the figure.

[0465] In this embodiment, when the pulmonary radiofrequency ablation system starts working, the control module 140 controls the micro-perfusion pump 130 to perfuse saline solution into the ablation catheter 110. When the control module 140 receives information that the impedance increases sharply from the impedance sensor, the micro-perfusion pump 130 is controlled to increase the perfusion amount of saline solution. In other embodiments, when the pulmonary radiofrequency ablation system starts working, the micro-perfusion pump 130 does not perfuse saline solution. When the control module 140 receives information that the impedance increases sharply from the impedance sensor, the micro-perfusion pump 130 is controlled to perfuse saline solution into the ablation catheter 110.

[0466] See also Fig. 22 , Fig. 22 FIG. 1 is a schematic diagram of a lung radiofrequency ablation system according to another embodiment of the present application.

[0467] In this embodiment, the lung radiofrequency ablation system includes a radiofrequency signal generator 100 , an ablation catheter 110 , an electrode plate, a sensor module 120 , a micro-infusion pump 130 and a control module 140 .

[0468] In this embodiment, the RF signal generator 100 is connected to the control module 140 , and is used to receive a command from the control module 140 to generate a RF signal, and transmit the RF signal to the ablation catheter 110 .

[0469] In this embodiment, the ablation catheter 110 has an electrical transmission channel for electrical transmission and a transmission channel for liquid transmission. The RF signal generator 100 is connected to the electrical transmission channel, and the liquid transmission channel is connected to the micro-infusion pump 130. The ablation catheter 110 can receive the RF signal generated by the RF signal generator 100, and apply the RF signal to the ablated tissue when puncturing the ablated tissue. It can also receive the saline solution infused by the micro-infusion pump 130. The front end of the ablation catheter 110 (the end that extends into the human body) is provided with a liquid outlet for infusing the saline solution into the ablated tissue when puncturing the ablated tissue. In other embodiments, other structures can be provided on the ablation catheter 110, as long as the effect of infusing the saline solution into the ablated tissue is achieved. For example, the ablation catheter 110 has a bendable structure, and the bending structure can be controlled to bend the front end of the ablation catheter 110 so as to accurately deliver the front end of the ablation catheter 110 to the treatment site; and / or, an operating unit for controlling the bending structure can be provided on the outside of the ablation catheter for medical staff to operate to control the degree of bending of the bending structure.

[0470] Specifically, under the guidance of B-ultrasound or CT, the ablation catheter 110 punctures into the ablation tissue through the puncture point via a bronchoscope, and transmits the radio frequency signal to the ablation tissue. At this time, the electrode plate connected to the radio frequency generator 100 and attached to the patient's body is connected to the ablation catheter 110 to form an electric field. The ablation tissue is also in the electric field. The high-frequency current acts on the human tissue between the two, causing the tumor cells contacted by the electrode at the far end of the radio frequency ablation catheter to coagulate, degenerate, and necrotize. Among them, the ablation catheter 110 is only an electrode for transmitting energy. The increase in its temperature is caused by the high-speed oscillation and mutual friction of ions in the tumor tissue near the ablation catheter 110 after the loop is formed, and the radio frequency energy is converted into heat energy. In other words, the ablation catheter 110 is passively heated due to the heating of the nearby tissue. After the tissue is electrified, it will dry and carbonize, forming a "scab" around the ablation catheter 110, "vacuum-wrapping" the ablation catheter 110, and the impedance between the ablation catheter 110 and the "scab" tissue will instantly become very large (i.e., the effects of heat sink and high impedance during radiofrequency ablation), which will cause the ablation to stop, resulting in incomplete ablation and insufficient ablation range. In this embodiment, the ablation catheter 110 is provided with a liquid outlet to inject saline into the ablation tissue. Since saline is a conductor, after infiltrating the ablation tissue, the impedance can be ensured to be stable within a certain range during the entire ablation process, so that the radiofrequency energy can be continuously output, thereby forming a sufficiently large ablation range and producing a larger and more effective coagulation necrosis focus.

[0471] In this embodiment, the sensor module 120 is disposed on the ablation catheter 110, and the sensor module 120 is connected to the control module 140. Specifically, the sensor module 120 is disposed at one end of the ablation catheter 110 that contacts the ablation tissue. The sensor module 120 includes an impedance sensor and a temperature sensor, which are used to detect the impedance and temperature of the contact position between the ablation catheter 110 and the ablation tissue and send the temperature information and impedance information to the control module 140; specifically, the temperature sensor can be a thermocouple. In this embodiment, the impedance information is acquired by the impedance sensor and transmitted to the control module 140. In other embodiments, the impedance information can be calculated based on the voltage and current values ​​collected by the system. Specifically, the real-time voltage and current values ​​are measured by a voltage and current measuring device and transmitted to the control module 140. The control module 140 calculates the impedance based on the real-time voltage and current values. In other embodiments, the sensor module 120 may also include other types of sensors such as flow sensors and pressure sensors for detecting the flow of saline and other data such as the pressure at the contact position between the ablation catheter 110 and the ablated tissue, so as to monitor the ablation situation and handle abnormalities in a timely manner. For example, when the flow information of saline transmitted by the flow sensor is lower than a certain threshold, the control module 140 controls the micro-infusion pump 130 to increase the infusion volume of saline to avoid "scab" of human tissue. In other embodiments, the type and number of sensors of the sensor module can be set according to the needs and actual conditions of the pulmonary radiofrequency ablation system during operation to monitor the ablation situation.

[0472] In this embodiment, the micro perfusion pump 130 is connected to the control module 140 and the ablation catheter 110, and is used to receive a command from the control module 140 to perfuse physiological saline into the ablation catheter 110. In other embodiments, the micro perfusion pump 130 can receive a command from the control module 140 to perfuse other liquids into the ablation catheter 110, and it is only necessary to improve the electrical conductivity and thermal conductivity of the ablated tissue, maintain impedance balance, keep the impedance in a relatively stable state, reduce the temperature of the ablated tissue, increase the humidity of the ablated tissue, and fundamentally avoid the effect of ablation tissue scabbing due to drying and heating, and not to cause serious side effects to the human body.

[0473] In this embodiment, the control module 140 is connected to the RF signal generator 100, the sensor module 120 and the micro-perfusion pump 130. Specifically, the control module 140 is used to control the RF signal generator 100 to generate RF signals. Specifically, the control module 140 receives the impedance information and temperature information detected by the sensor module 120, and controls the micro-perfusion pump 130 to perfuse saline into the ablation catheter 110 based on the impedance information. In this embodiment, if the impedance sensor detects a sharp increase in impedance, it means that the tissue near the electrode of the ablation catheter 110 is drying and carbonizing, and scabs will form. After receiving the impedance information from the impedance sensor, the control module 140 controls the micro-perfusion pump 130 to increase the perfusion amount of saline. In this embodiment, the control module 140 is also used to determine whether the perfusion of saline is unobstructed based on the temperature information to monitor the ablation situation. In other embodiments, the control module 140 can make a comprehensive judgment on the ablation situation based on the data transmitted by multiple sensors, and control the micro-infusion pump 130, the radio frequency signal generator 100 and other equipment to adjust when the preset conditions are met to ensure the smooth progress of the ablation process. The preset conditions can be set by the user according to the actual situation when the lung radiofrequency ablation system is working and the setting of the sensor. In other embodiments, the impedance information can be calculated based on the voltage and current values ​​collected by the system. Specifically, the real-time voltage and current values ​​are measured by a voltage and current measuring device and transmitted to the control module 140, and the control module 140 calculates the impedance based on the real-time voltage and current values.

[0474] The electrode plate is connected to the radio frequency signal generator and is used to form a loop with the electrode in the ablation catheter through the human body.

[0475] The electrode plate is attached to the appropriate part of the patient's body. During the ablation operation, the electrode in the ablation catheter forms a working circuit (i.e. the aforementioned circuit where the electrode is located) through the human body and the electrode plate. The high-frequency current acts on the human tissue between the two, causing the lesion site contacted by the electrode to coagulate, degenerate, and necrotize. The electrode plate itself is a conventional component of the ablation operation and is omitted in the figure.

[0476] In this embodiment, when the pulmonary radiofrequency ablation system starts working, the control module 140 controls the micro-perfusion pump 130 to perfuse saline solution into the ablation catheter 110. When the control module 140 receives information that the impedance increases sharply from the impedance sensor, the micro-perfusion pump 130 is controlled to increase the perfusion amount of saline solution. In other embodiments, when the pulmonary radiofrequency ablation system starts working, the micro-perfusion pump 130 does not perfuse saline solution. When the control module 140 receives information that the impedance increases sharply from the impedance sensor, the micro-perfusion pump 130 is controlled to perfuse saline solution into the ablation catheter 110.

[0477] The present application also provides a lung radiofrequency ablation method in different embodiments, which can be implemented using the relevant components, devices or systems of the aforementioned embodiments.

[0478] Lung radiofrequency ablation methods include:

[0479] Controlling the radio frequency signal generator to generate a radio frequency signal and transmitting the radio frequency signal to the ablation catheter;

[0480] Acquiring impedance information and temperature information of the contact position between the ablation catheter and the ablation tissue;

[0481] Based on the impedance information, a micro-infusion pump is controlled to infuse physiological saline into the ablation catheter, and based on the temperature information, an alarm module is controlled to alarm.

[0482] The specific process and details of the pulmonary radiofrequency ablation method can also be found in the following description of the control method of pulmonary radiofrequency ablation.

[0483] Different embodiments of the present application also provide a method for monitoring temperature and impedance during pulmonary radiofrequency ablation, which can be implemented using the relevant components, devices or systems of the aforementioned embodiments.

[0484] Methods for monitoring temperature and impedance during pulmonary radiofrequency ablation include:

[0485] Controlling the radio frequency signal generator to generate a radio frequency signal and transmitting the radio frequency signal to the ablation catheter;

[0486] Acquiring impedance information and temperature information of the contact position between the ablation catheter and the ablation tissue;

[0487] Based on the impedance information, a micro-infusion pump is controlled to infuse physiological saline into the ablation catheter, and based on the temperature information, an alarm module is controlled to alarm.

[0488] The specific process and details of the method for monitoring the temperature and impedance of pulmonary radiofrequency ablation can also be found in the following description of the control method for pulmonary radiofrequency ablation.

[0489] In one embodiment of the present application, a control method for pulmonary radiofrequency ablation is disclosed.

[0490] In this embodiment, the control method of pulmonary radiofrequency ablation includes:

[0491] Step 300: Control the radio frequency signal generator to generate a radio frequency signal and transmit the radio frequency signal to the ablation catheter.

[0492] Specifically, the control module controls the RF signal generator to generate a RF signal and transmits the RF signal to the ablation catheter. After the ablation catheter punctures into the ablation tissue, the RF signal is transmitted to the ablation tissue. The RF signal is converted into heat energy in the loop and acts on the ablation tissue, causing the tumor cells contacted by the electrode at the distal end of the ablation catheter to coagulate, degenerate, and necrotize.

[0493] Step 310: Obtain impedance information and temperature information of the contact position between the ablation catheter and the ablation tissue.

[0494] Specifically, during radiofrequency ablation, the heat energy generated will cause the temperature of human tissue to rise, causing the human tissue near the ablation catheter to dry and carbonize, forming a "scab". The resistance between the electrode and the "scab" suddenly becomes very large, causing the ablation to stop and the ablation to be incomplete. At this time, the impedance sensor detects a sharp increase in impedance and transmits the impedance information to the control module. The temperature sensor detects the temperature information and transmits it to the control module.

[0495] In other embodiments, the impedance information can be calculated based on the voltage and current values ​​collected by the system. Specifically, the real-time voltage and current values ​​are measured by a voltage and current measuring device and transmitted to the control module, and the control module calculates the impedance based on the real-time voltage and current values.

[0496] Step 320: Control a micro-infusion pump to infuse physiological saline into the ablation catheter based on the impedance information, and control an alarm module to sound an alarm based on the temperature information.

[0497] Specifically, after receiving the information of the impedance increase transmitted by the impedance sensor, the control module controls the micro-infusion pump to increase the infusion volume of physiological saline, and the physiological saline is infused into the ablation catheter and into the ablation tissue through the outlet hole on the ablation catheter, thereby improving the conductivity and thermal conductivity of the tissue, maintaining the impedance balance, and keeping the impedance in a relatively stable state. At the same time, the temperature of the tissue is reduced, the humidity of the tissue is increased, and the tissue is fundamentally prevented from scabbing due to drying and heating. The impedance is ensured to be stable within a certain range during the entire ablation process, so that the radio frequency energy can be continuously output, thereby forming a sufficiently large ablation range and producing a larger and more effective coagulation necrosis focus. In addition, the control module also receives the temperature information transmitted by the temperature sensor. If the temperature rises above a certain threshold during the ablation process, the control module determines that the infusion of the physiological saline is blocked, issues an alarm command, and controls the alarm module to issue an alarm signal to prompt, so as to ensure the smooth progress of the ablation process.

[0498] In another embodiment of the present application, a control method for pulmonary radiofrequency ablation is disclosed.

[0499] In this embodiment, the control method of pulmonary radiofrequency ablation includes:

[0500] Step 400: Control the radio frequency signal generator to generate a radio frequency signal and transmit the radio frequency signal to the ablation catheter.

[0501] Specifically, the control module controls the RF signal generator to generate a RF signal and transmits the RF signal to the ablation catheter. After the ablation catheter punctures into the ablation tissue, the RF signal is transmitted to the ablation tissue. The RF signal is converted into heat energy in the loop and acts on the ablation tissue, causing the tumor cells contacted by the electrode at the distal end of the ablation catheter to coagulate, degenerate, and necrotize.

[0502] Step 410: Obtain impedance information of the contact position between the ablation catheter and the ablation tissue.

[0503] Specifically, during radiofrequency ablation, the heat energy generated will cause the temperature of human tissue to rise, causing the human tissue near the ablation catheter to dry and carbonize, forming a "scab". The resistance between the electrode and the "scab" suddenly becomes very large, causing the ablation to stop and the ablation to be incomplete. At this time, the impedance sensor detects a sharp increase in impedance and transmits the impedance information to the control module.

[0504] In other embodiments, the impedance information can be calculated based on the voltage and current values ​​collected by the system. Specifically, the real-time voltage and current values ​​are measured by a voltage and current measuring device and transmitted to the control module, and the control module calculates the impedance based on the real-time voltage and current values.

[0505] Step 420: Control a microinfusion pump to infuse physiological saline into the ablation catheter based on the impedance information.

[0506] Specifically, after the control module receives the information of the sharp increase in impedance transmitted by the impedance sensor, it controls the micro-infusion pump to increase the infusion volume of physiological saline. The physiological saline is infused into the ablation catheter and into the ablation tissue through the outlet hole on the ablation catheter, thereby improving the electrical conductivity and thermal conductivity of the tissue, maintaining the impedance balance, and keeping the impedance in a relatively stable state. At the same time, the temperature of the tissue is reduced, the humidity of the tissue is increased, and the scabbing of the tissue due to drying and heating is fundamentally avoided. During the entire ablation process, the impedance is ensured to be stable within a certain range, and the radio frequency energy can be continuously output, thereby forming a sufficiently large ablation range and producing a larger and more effective coagulation necrosis lesion.

[0507] Exemplarily, when the lung radiofrequency ablation system is working, the control module controls the radiofrequency signal generator to generate a radiofrequency signal and transmits the radiofrequency signal to the ablation catheter. After the ablation catheter punctures into the ablation tissue, the radiofrequency signal is transmitted to the ablation tissue. The radiofrequency signal is converted into heat energy in the loop and acts on the ablation tissue, causing the tumor cells contacted by the electrode at the distal end of the ablation catheter to coagulate, degenerate, and necrotize. During ablation, the heat energy generated will cause the temperature of human tissue to rise, causing the human tissue near the ablation catheter to dry and carbonize, forming a "scab". The resistance between the electrode and the "scab" suddenly becomes very large, causing the ablation to stop and the ablation to be incomplete. At this time, the impedance sensor detects a sharp increase in impedance and transmits the impedance information to the control module. After the control module receives the impedance information from the impedance sensor, or after the control module calculates the impedance based on the real-time voltage and current information, it controls the micro-infusion pump to increase the infusion volume of physiological saline. The physiological saline is infused into the ablation catheter and into the ablated tissue through the outlet hole on the ablation catheter, thereby improving the electrical conductivity and thermal conductivity of the tissue, maintaining impedance balance, and keeping the impedance in a relatively stable state. At the same time, the temperature of the tissue is reduced, the humidity of the tissue is increased, and the scab of the tissue due to drying and heating is fundamentally avoided. The impedance is ensured to be stable within a certain range during the entire ablation process, so that the radio frequency energy can be continuously output, thereby forming a sufficiently large ablation range and producing a larger and more effective coagulation necrosis focus. In addition, the control module also receives temperature information transmitted by the temperature sensor. If the temperature rises above a certain threshold during the ablation process, the control module determines that the perfusion of physiological saline is blocked, issues an alarm command, and controls the alarm module to issue an alarm signal to prompt, so as to ensure the smooth progress of the ablation process.

[0508] The above-mentioned lung radiofrequency ablation system and control method detect the impedance change of the ablated tissue through an impedance sensor. When a sharp increase in impedance is detected, it means that the ablated tissue near the electrode is drying and carbonizing, and scabs will form. At this time, physiological saline is controlled to be perfused into the ablated tissue to reduce the temperature of the tissue and increase the humidity of the tissue, thereby fundamentally avoiding the formation of scabs due to drying and heating of the tissue. At the same time, physiological saline can improve the electrical conductivity and thermal conductivity of the tissue, maintain impedance balance, and keep the impedance in a relatively stable state. The combination of the two ensures that the impedance is stable within a certain range during the entire ablation process, so that the radiofrequency energy can be continuously output, thereby forming a sufficiently large ablation range and producing a larger and more effective coagulation necrosis focus.

[0509] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0510] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A radiofrequency ablation catheter, comprising an electrode, characterized in that: The distal end of the electrode is pointed and has a heat exchange medium flow channel. The electrode is provided with a balancing device, and the balancing device is provided with an infiltration hole connected to the heat exchange medium flow channel. The heat exchange medium output from the heat exchange medium flow channel is distributed and flows out through the balancing device; the outer wall of the electrode is provided with an outflow hole connected to the heat exchange medium flow channel, and the balancing device is an infiltration cover installed on the electrode, at least a part of the infiltration cover is a permeation area with infiltration holes distributed, the position of the electrode where the outflow hole is provided corresponds to the permeation area, and a gap is left between the electrode and the inner wall of the permeation area, and the gap is formed by local sedimentation of the outer wall of the electrode and / or local bulge of the infiltration cover; the gap can distribute the heat exchange medium to change the pressure or flow of the heat exchange medium at different parts of the infiltration cover; the distance from adjacent outflow holes is different, and the gap changes accordingly; The radio frequency ablation catheter further comprises a plurality of temperature detection devices arranged on the outer wall of the radio frequency ablation catheter, and the plurality of temperature detection devices are sequentially distributed along the axial direction adjacent to the distal end of the radio frequency ablation catheter.

2. The radiofrequency ablation catheter according to claim 1, characterized in that: The equalizing device and the electrode are an integrated structure, and the wetting hole is arranged on the outer wall of the electrode.

3. The radiofrequency ablation catheter according to claim 1, characterized in that: The distal end of the electrode is a cone or a pyramid.

4. The radiofrequency ablation catheter according to claim 1, characterized in that: The distal end of the electrode is formed by chamfering one of a spherical cap, a truncated cone, and a prism using at least one surface to form the tip.

5. The radiofrequency ablation catheter according to claim 1, characterized in that: The distal end of the electrode is a cylinder, and the tip is formed by beveling three surfaces of the cylinder.

6. The radiofrequency ablation catheter according to claim 1, characterized in that: The heat exchange medium flow channel includes a main flow channel and a plurality of branch flow channels connected to the main flow channel, and the end of each branch flow channel extends to the outer surface of the electrode.

7. The radiofrequency ablation catheter according to claim 6, characterized in that: There is one main flow channel, which is set at the axial position of the electrode and extends along the axial direction of the electrode. Multiple branch flow channels are connected at different positions of the main flow channel; the branch flow channels are arranged in at least one group along the extension direction of the main flow channel, and there are at least two branch flow channels in the same group, which are radially distributed on the periphery of the main flow channel, and the branch flow channels in the same group are evenly arranged in the circumferential direction; the number of branch flow channels in adjacent groups is the same or different, and the positions in the circumferential direction are aligned or staggered.

8. The radiofrequency ablation catheter according to claim 1, characterized in that: The infiltration holes are arranged regularly in a certain manner or path around the periphery of the electrode; The infiltration holes are distributed at the same density at different locations on the periphery of the electrode, or are arranged accordingly according to the balance of heat exchange medium flow.

9. The radiofrequency ablation catheter according to claim 1, characterized in that: The axial position of at least one temperature detection device is adjustable, and a mutually matching guide structure is provided between the radiofrequency ablation catheter and the temperature detection device; and / or At least one temperature detection device is fixedly installed, and the temperature detection device includes a temperature sensor and a thermally conductive ring; the thermally conductive ring is arranged on the outer wall of the radio frequency ablation catheter, and the temperature sensor is thermally coupled with the thermally conductive ring; the outer wall of the radio frequency ablation catheter is provided with an embedding groove, and the temperature sensor is fixed in the embedding groove at a corresponding position through the thermally conductive ring, and the bottom of the embedding groove is provided with a first through hole for passing the circuit wire.

10. An ablation system, characterized in that include: The radiofrequency ablation catheter according to any one of claims 1 to 9; A heat exchange medium delivery device for providing heat exchange medium to the peripheral area of ​​the electrode of the radiofrequency ablation catheter; The control module of the heat exchange medium conveying device is driven accordingly according to the impedance information or temperature information of the loop where the electrode in the radio frequency ablation catheter is located.

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