Freezing radiofrequency ablation catheter and system

Abstract

The invention discloses a cryoradiofrequency ablation catheter and system, and belongs to the technical field of cryoablation, the cryoradiofrequency ablation catheter comprises a needle catheter part, a handle, a catheter extension tube assembly, a plug assembly, a vacuum plug assembly and a cable plug assembly; the needle head catheter part is flexible; a far-end connecting needle catheter part of a near-end connecting catheter extension tube assembly is handheld and used by a user, and the far end of the catheter extension tube assembly is connected with a handle near-end connecting plug assembly; the far end of the plug assembly is connected with the near end of the catheter extension tube assembly; the far end of the vacuum plug assembly is connected with the plug assembly and extends into the vacuum layer of the needle catheter part. The high-pressure nitrogen or argon throttling freezing technology is used as a freezing mode, only the front-end flexible guide pipe section needs to be subjected to vacuum heat insulation, and the pressure resistance characteristic and local heat insulation of the pipeline and the connector are optimized. Meanwhile, a rewarming module and a radiofrequency ablation module are added on the basis of the cryoablation probe, and central control switching of the three modules is achieved.

Description

Technical Field

[0001] This invention belongs to the field of cryoablation technology, and particularly relates to a cryoradioablation catheter and system. Background Technology

[0002] With the development of science and technology, especially the advancement of medical imaging technology, minimally invasive surgeries such as cryotherapy and thermal ablation for tumors have made significant progress. However, they still have their own limitations. Direct thermal ablation, represented by radiofrequency ablation, is related to the temperature received by the tissue, typically between 41℃ and 45℃, which can cause irreversible cell damage. When the tissue temperature rises to 60℃, the time for irreversible cell damage is greatly shortened. Above 60℃, protein denaturation occurs, and within this temperature range, coagulation necrosis occurs. When the temperature continues to rise to around 100℃, the water within the tissue boils and vaporizes. If the temperature continues to rise, the tissue will carbonize and produce smoke. Once carbonization occurs, the temperature rises rapidly. Simultaneously, thermal resistance limits the extent of tissue damage, and carbonization increases interstitial pressure, potentially leading to the spread of cancer cells into the liver and blood vessels. The advantages of thermal ablation include the ability to inactivate target tissue within a defined temperature range, rapid hemostasis via the needle tract, and high thermal efficiency. However, thermal ablation requires addressing the issue of controlling the temperature to prevent it from becoming too high. Common control methods involve introducing a circulating cooling system (such as water cooling or air cooling). In addition, the disadvantages of radiofrequency thermal ablation include significant pain for patients during the procedure, poor visibility of the ablation area making it difficult to accurately determine the boundaries of the ablation zone, and the potential for tissue damage or needle sticking.

[0003] Cryoablation primarily involves the controlled cooling, freezing, and rewarming of lesion tissue using cryo-instruments, resulting in irreversible damage and even necrosis of tumor cells. The mechanisms by which cryoablation kills tumor cells include: cell dehydration and shrinkage; mechanical damage from intracellular ice crystal formation; cellular electrolyte concentration and pH changes; denaturation of cell membrane proteins; blood stasis and microthrombus formation; and immune effects. Cryoablation is not only minimally invasive but also offers advantages such as precise localization, hemostasis and analgesia, fewer postoperative complications, high safety, and activation of tissue immunity, making it highly popular among doctors and patients. However, cryoablation has drawbacks, including the potential for residual tumor cells due to incomplete ablation and poor hemostasis during and after the procedure. Therefore, designing a product compatible with both cryoablation and radiofrequency ablation, allowing for seamless switching between modes, can not only compensate for the shortcomings of single-method cryoablation and single-method thermoablation, but also facilitate thorough eradication of target tissue, improving tumor cure rates, while protecting normal tissue from damage, thus fully leveraging the advantages of each method.

[0004] Existing technology CN113558746A describes a multimodal tumor ablation probe system and its control method. This technology relies on low-pressure liquid nitrogen freezing as the freezing mode, adding a radiofrequency generator to the cryoablation device and achieving a certain degree of switching between cold and thermal ablation. During freezing, liquid nitrogen flows into the lumen of the treatment section through the inlet pipe, undergoes phase change heat, and then flows out of the probe through the return gas channel. During heating, the probe receives radiofrequency current through the radiofrequency signal line. However, this liquid nitrogen cooling technology, due to the use of a low-temperature medium, requires consideration of the insulation characteristics of the pipeline to prevent significant heat leakage and difficulties in effectively controlling the cooling rate. Furthermore, during radiofrequency thermal ablation, the liquid nitrogen system must be completely suspended and not participate in cooling; the radiofrequency energy is generated by the radiofrequency electrodes without using cooling cycle control (such as commonly used water cooling or air cooling). Switching from freezing mode to radiofrequency ablation mode requires the body to melt to meet the conditions for radiofrequency ablation before thermal ablation can be performed. Meanwhile, the ablation probe used in this probe system is a traditional hard needle structure. Therefore, the original design system is only suitable for percutaneous surgery, which significantly increases the risk of external trauma and pneumothorax bleeding for patients. It is limited compared to flexible catheter products that can pass through natural cavities.

[0005] Therefore, developing a flexible cryo-radiofrequency ablation catheter suitable for use through natural cavities is of great significance and can better expand its practical applications. Summary of the Invention

[0006] This invention provides a cryoradioablation catheter and system to solve the problems in the prior art.

[0007] The present invention employs the following technical solution: a cryoradiofrequency ablation catheter, comprising a needle catheter portion, a handle, a catheter extension tube assembly, a plug assembly, a vacuum plug assembly, and a cable plug assembly; the needle catheter portion is flexible; the proximal end of the catheter extension tube assembly is connected to the distal end of the needle catheter portion for user hand-held use, the distal end of the catheter extension tube assembly is connected to the handle, and the proximal end of the plug assembly is connected to the plug assembly; the distal end of the plug assembly is connected to the catheter extension tube assembly, and the proximal end is connected to the device socket portion for product insertion, removal, and fixation; the distal end of the vacuum plug assembly is connected to the plug assembly and extends into the vacuum layer of the needle catheter portion, and the proximal end is connected to the device vacuum socket position; the distal end of the cable plug assembly is connected to the plug assembly and extends into the needle catheter portion.

[0008] Furthermore, the needle guide portion is internally provided with a JT groove, a rewarming wire, a thermocouple, and an inner wall tube; the distal end of the needle guide portion is a metal needle blade shell, and the proximal end is a non-metallic flexible outer wall tube. The needle blade shell is divided into a needle blade shell end cap and a needle blade shell connector. The inner wall tube is fixed to the inner wall of the needle blade shell connector, and the outer wall tube is fixed in the double-layer structure of the needle blade shell connector, forming a vacuum layer in the middle. The JT groove and various signal transmission lines form an integral whole, passing through the inside of the inner wall tube and reaching the interior of the distal needle blade shell.

[0009] Furthermore, the handle includes a handle housing, a handle bend protector, a handle fixing member, and a tee structure. The handle housing provides support, the handle bend protector connects to the handle housing and provides bend protection and support for the proximal portion of the needle guide tube, the handle fixing member connects to the proximal guide tube extension tube and the distal end connects to the handle housing for overall product connection and fixation, and the tee structure is designed to be placed inside the handle housing.

[0010] Furthermore, the conduit extension tube assembly includes an outer conduit extension tube, an inlet extension tube, a return extension tube, a vacuum extension tube, a rewarming line extension tube, and a thermocouple extension tube. The distal end of the inlet extension tube is directly connected to the JT groove, the distal end of the return extension tube is directly connected to the inner wall tube through one port of the handle's internal tee structure, the vacuum extension tube is connected to the vacuum layer through the other port of the tee structure, the distal end of the rewarming line extension tube is directly connected to the rewarming line, and the distal end of the thermocouple extension tube is directly connected to the thermocouple.

[0011] Furthermore, the plug assembly includes a quick plug, a plug handle upper part, and a plug handle lower part. The quick plug is assembled with the plug handle upper part and the plug handle lower part by a snap-fit ​​structure, and the quick plug is used directly in conjunction with a socket on the device.

[0012] Furthermore, the cable plug assembly includes a cable plug and a cable plug extension tube. The cable plug extension tube contains a reheating wire extension line, a temperature measuring thermocouple extension line, and a radio frequency cable, which respectively transmit reheating electric heating signals, temperature signals, and radio frequency transmission signals.

[0013] Furthermore, the vacuum plug assembly is a vacuum plug, and two openings are reserved on the lower and upper parts of the plug handle. The two openings on the lower and upper parts of the plug handle can respectively pass through the vacuum extension tube and the cable plug extension tube and connect to the vacuum plug and the cable plug to form a vacuum plug assembly and a cable plug assembly.

[0014] A cryo radiofrequency ablation catheter system includes a cryo radiofrequency ablation catheter, and also includes a cryoablation module, a radiofrequency ablation module, a rewarming module and a control center. Each module can be freely switched through the control center; high-pressure gas is used as the gas source, and the distal flexible catheter has a double-layer catheter structure, and the middle interlayer has a vacuum insulation function.

[0015] Further, a pressure proportional solenoid valve with temperature control function adjustment is introduced in the cryoablation module. The gas source is input into the solenoid valve II to have a pressure of P1, and after passing through the flow proportional valve, it becomes P2, and then after passing through the precooling device, it reaches the probe head end for cryoablation.

[0016] Further, the radiofrequency ablation module includes a radiofrequency transmitting device and a probe. The radiofrequency transmitting device generates radiofrequency energy at the probe head. A detector is connected to the outside of the probe head, and the system is connected to a temperature control structure; the original cryoablation module becomes a cooling function module. The input air pressure of the gas source becomes P2 after passing through the solenoid valve II, and is adjusted to P3 after passing through the pressure proportional valve. P3 < P2 and is controlled and adjusted by the feedback temperature signal T2.

[0017] The above at least one technical solution adopted in the embodiments of the present invention can achieve the following beneficial effects:

[0018] (1) Based on the cryoablation probe using high-pressure nitrogen or argon throttling cryo technology, a rewarming module and a radiofrequency ablation module are added, realizing the central control switching of the three modules, and achieving an integrated structure design of the cryo module + rewarming module + radiofrequency module. This integrated structure can be used jointly by multiple modules or independently, realizing the mutual complementation of the functions of cryoablation and thermal ablation.

[0019] (2) By integrating cryoablation and radiofrequency ablation onto a flexible ablation catheter at the same time, it can effectively improve the application of ablation technology in the field of natural channels. With the development of imaging technologies such as endoscopy or ultrasound, the safety of the surgical path is further improved, improving the limitations of the original invasive percutaneous ablation, and expanding the application space of the product.

[0020] (3) By adding a rewarming module, a rapid transition from cryoablation first and then radiofrequency ablation is achieved. Since cryoablation can cause the tissue impedance to be too high to perform effective radiofrequency ablation, generally a long natural rewarming is required before radiofrequency ablation can be performed. The introduced rewarming module can reach a relatively high temperature in a short time by the heat generation of the thermocouple, melting the target frozen tissue of the body and quickly rewarming to the condition for radiofrequency ablation, thereby greatly shortening the time from cryoablation to radiofrequency ablation and improving the surgical efficiency.

[0021] (iv) By introducing high-pressure nitrogen or argon into the radio frequency module as a cooling circulation medium, which is shared with the gas source of the cryo-radio frequency module, the effective control of excessive temperature during radio frequency ablation is achieved, and the effective utilization of the same gas source is improved, which simplifies the structure of the cryo-radio frequency ablation conduit.

[0022] (v) By introducing a pressure proportional valve solenoid valve + temperature controller, the temperature controller receives signal feedback from the temperature sensor at the front end of the cryo-radiofrequency ablation catheter and controls the electronic pressure proportional valve to output the corresponding pressure and flow rate of gas. Since excessively high temperature during radiofrequency ablation will damage tissue and excessively low temperature will affect ablation efficiency, this kind of temperature control system with feedback mechanism is needed, so as to realize dynamic control of the thermal ablation cooling cycle system and ensure the stability of thermal ablation.

[0023] (vi) The selection of temperature monitoring points is particularly important for signal feedback and control of the thermal ablation cooling cycle system. This invention provides multiple location options for temperature monitoring, making the selection of temperature more diverse. Users can make choices according to actual conditions, which is conducive to achieving multi-angle monitoring.

[0024] (vii) By placing the temperature detection point in the internal needle tip shell, the product can collect data on the highest temperature peak of common radiofrequency ablation without compromising its integrity and usability, thus ensuring temperature control of radiofrequency ablation.

[0025] (viii) By introducing the concept of a three-way structure, the vacuum layer can be separated from the inlet and outlet pipes, avoiding problems such as vacuum layer failure caused by the connection between the inlet and outlet pipes and the vacuum layer.

[0026] (ix) The needle tip housing can be manufactured as a separate unit, specifically by dividing the manufacturing process into the needle tip housing end cap and the needle tip housing connector. This design facilitates the implementation of solutions requiring pre-welding and fixing of the thermocouple to the top of the head. Specifically, the top is machined with bottom holes to pre-drill welding positions. After the wire or JT groove to be welded is fixed to the needle tip housing end cap, it is reversed and installed onto the needle tip housing connector. The needle tip housing end cap and the needle tip housing connector are connected by laser welding. The other end of the needle tip housing connector connects to both the inner and outer tube walls, connecting the conduit section and sealing the inner and outer tube walls to ensure a vacuum layer. This structure can generally be fixed using adhesive bonding or riveting.

[0027] (x) By designing the needle blade shell connector as a double-walled structure, the distal end of the needle blade shell connector is welded and sealed, and the proximal end is a double-layered sandwich structure. This allows it to connect with the inner and outer wall tubes at the proximal end, making the vacuum layer seal of this structure more stable and secure. At the same time, when designing the sandwich structure, the size matching of the inner and outer wall tubes should be considered, and users can make adjustments according to different channel specifications.

[0028] (xi) The blank shape of the needle tip end cap is generally machined from bar stock. During machining, it should be made into a semi-hollow structure. The reserved hole diameter (generally recommended to be centered) of 0.5mm to 0.8mm is appropriate, and the depth should not exceed 1 / 2 of the end cap. In actual use, the influence of factors such as the limit of the machinable depth and the required measurement depth needs to be considered. The recommended welding method for welding the temperature measuring thermocouple to the hole inside the needle tip end cap is spot soldering, so that the welding area is completely filled with solder to avoid problems such as weak welding or lack of conductivity.

[0029] (xii) By placing the temperature monitoring point on the internal JT tank, the internal temperature of the product can be detected, and the product assembly and processing can be facilitated. It is also beneficial to provide real-time feedback on the real-time temperature of the cooling system and to better control the corresponding temperature range by controlling the internal air source.

[0030] (xiii) By fixing the JT slot to the inside of the proximal blade housing, the metal conduction function between the JT slot and the blade housing can be effectively ensured. At the proximal end, only the radio frequency cable needs to be connected to the outer wall of the proximal air inlet extension tube connected to the JT slot to realize the conduction of the radio frequency circuit, so that the radio frequency function of the product of the present invention can be realized, reducing the tediousness of rearranging the circuit.

[0031] (XIV) By fixing the JT slot to the inner top of the distal blade housing, the metal conduction function between the JT slot and the blade housing can be effectively guaranteed. At the proximal end, only the RF cable needs to be connected to the outer wall of the proximal air inlet extension tube connecting the JT slot to achieve RF circuit conduction, enabling the RF function of the product of this invention to be realized and reducing the cumbersome process of rewiring. Since the vent of the distal JT slot is welded closed, by adding an exhaust port on the distal side of the JT slot, the smooth entry of cold air during cryoablation can be guaranteed without affecting the operation of the freezing mode and cooling mode.

[0032] (XV) By fixing the RF connection cable to the top inner side of the needle housing end cap, the solution to the problem of the JT slot needing to be fixed at a remote end can be solved. This solution eliminates the need to conduct the RF function through the JT slot to the needle housing. This design makes the installation of the JT slot simpler, requiring only the RF connection cable to be pre-soldered to the top inner side of the housing.

[0033] (xvi) By fixing the radio frequency connection line and the temperature measuring thermocouple to the top of the inner side of the blade housing at the same time, the cumbersome processing of fixing the temperature measuring thermocouple to the JT slot can be reduced, and the highest radio frequency temperature point can be monitored in real time, which is beneficial for adjustment and PID feedback control.

[0034] (XVII) By using a shared blade shell structure for cryoablation and radiofrequency ablation, the target areas of cryoablation and radiofrequency ablation are consistent. For the same target area, the structures of cold ablation and hot ablation are completely overlapped, which replaces the problem that the original multi-needle ablation scheme is difficult to achieve physical structure overlap.

[0035] (18) The flexible outer tube of the needle portion can be made of PTFE or PEBAX. To ensure the internal vacuum structure, the inner tube can be made of braided tubing made of materials such as PEBAX, PI, or PEEK. This effectively ensures the integrity of the vacuum layer and meets the high-pressure environment requirements for internal operation. The size of the catheter can be adjusted appropriately according to the size of the surgical channel (e.g., the size of the endoscope channel) or the target surgical area. The overall specifications of the needle portion can be varied, ensuring a wider range of applicability. The remaining proximal structural parts generally use a universal size design. Attached Figure Description

[0036] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0037] Figure 1 : A schematic diagram of a cryoradiofrequency ablation catheter system;

[0038] Figure 2 : A schematic diagram of a cryoablation module for a cryoradioablation catheter;

[0039] Figure 3 : A schematic diagram of a cryoablation catheter radiofrequency ablation module;

[0040] Figure 4 : A schematic diagram of a cryoradiofrequency ablation catheter rewarming module;

[0041] Figure 5 : A structural diagram of a cryoradioablation catheter;

[0042] Figure 6a : Diagram of the head structure of a cryoradioablation catheter;

[0043] Figure 6b Cross-sectional view of the needle shell of a cryoradioablation catheter;

[0044] Figure 6c Cross-sectional view of the vacuum layer assembly of the needle portion of the cryoradioablation catheter;

[0045] Figure 7 : Structural diagram of the cryoradioablation catheter handle assembly;

[0046] Figure 8: Structural diagram of the cryoradioablation catheter extension tube assembly;

[0047] Figure 9 :Structural diagram of the cryoradioablation catheter plug assembly;

[0048] Figure 10 : Structural diagram of cryoradioablation catheter cable plug assembly;

[0049] Figure 11 Schematic diagram of different temperature monitoring points when the cryoradioablation catheter is activated;

[0050] Figure 12 Schematic diagram of temperature curves at different temperature monitoring points when the cryoradioablation catheter is activated;

[0051] Figure 13 : Diagram of the head structure of a cryoradioablation catheter;

[0052] Figure 14a : Structural diagram of the intermediate temperature measurement scheme inside the JT groove for proximal fixation of cryoradioablation catheter;

[0053] Figure 14b Partial cross-sectional view of the intermediate temperature measurement scheme inside the JT groove for proximal fixation of cryoradioablation catheter.

[0054] Figure 15a : Structural diagram of the temperature measurement scheme at the top of the JT groove inside the proximal fixation of the cryoradioablation catheter;

[0055] Figure 15b : Partial cross-sectional view of the temperature measurement scheme at the top of the JT groove inside the proximal fixation of the cryo-radiofrequency ablation catheter;

[0056] Figure 16a : Structural diagram of the temperature measurement scheme at the top of the JT groove inside the distal fixation of the cryoradioablation catheter;

[0057] Figure 16b : Partial cross-sectional view of the temperature measurement scheme at the top of the JT groove inside the distal fixation of the cryo-radiofrequency ablation catheter;

[0058] Figure 17a : Structural diagram of a cryo-radiofrequency ablation catheter JT groove with non-fixed internal tip temperature monitoring including radiofrequency wire;

[0059] Figure 17b : Partial cross-sectional view of a cryo-radiofrequency ablation catheter JT groove non-fixed internal tip temperature monitoring scheme including radiofrequency wire. (See attached diagram with annotations.)

[0060] Needle guide tube 1, needle blade housing 101, needle blade housing end cap 1011, needle blade housing connector 1012, JT groove 102, JT groove side hole 1021, outer wall tube 103, rewarming wire 104, temperature measuring thermocouple 105, inner wall tube 106, vacuum layer 107, radio frequency connecting wire 108, welding point between needle blade housing and JT groove 109, welding point between needle blade housing and temperature measuring wire 110;

[0061] Handle 2, handle housing 201, handle bend protector 202, handle fixing part 203;

[0062] The conduit extension tube assembly 3, the conduit extension tube outer tube 301, the air inlet extension tube 302, the air return extension tube 303, the vacuum extension tube 304, the reheat line extension line 305, and the temperature measuring thermocouple extension line 306.

[0063] Plug assembly 4, quick plug 401, upper plug handle 402, lower plug handle 403;

[0064] Vacuum plug assembly 5, vacuum plug 501;

[0065] Cable plug assembly 6, cable plug 601, cable plug extension tube 602, radio frequency cable 603. Detailed Implementation

[0066] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0067] The following detailed description, in conjunction with the accompanying drawings, illustrates the technical solution of a cryoradioablation catheter and system provided by various embodiments of the present invention.

[0068] Reference Figures 1 to 17b As shown, this embodiment of the invention provides a cryoradiofrequency ablation catheter, such as... Figure 5As shown, the device includes a needle catheter portion 1, a handle 2, a catheter extension tube assembly 3, a plug assembly 4, a vacuum plug assembly 5, and a cable plug assembly 6. The needle catheter portion 1 is flexible, with a metal needle sheath 101 at the distal end, serving as the primary target area for cryotherapy or radiofrequency ablation, and a non-metallic flexible catheter outer tube 103 at the proximal end, allowing for flexible adjustment of the device's tip within natural cavities. The device is held by the user, with the proximal end connected to the catheter extension tube assembly 3 and the distal end connected to the needle catheter portion 1. The catheter extension tube assembly 3 is connected to the handle 2 at the distal end and the plug assembly 4 at the proximal end to extend the product's usability and prevent issues caused by the distance between the device and the patient. In cases where surgery is performed, it also serves as an entry and exit channel for heat or cold sources; the distal end of the plug assembly 4 is connected to the conduit extension tube assembly 3, and the proximal end is connected to the device socket to enable product insertion, removal, and fixation; the distal end of the vacuum plug assembly 5 is connected to the plug assembly 4 and extends into the vacuum layer 107 of the needle conduit part 1, and the proximal end is connected to the device vacuum socket position for evacuating the vacuum layer 107 of the needle conduit part 1; the distal end of the cable plug assembly 6 is connected to the plug assembly and extends into the temperature measuring wire, the rewarming wire 104, and the radio frequency wire of the needle conduit part 1, and the three wires eventually converge into the cable plug assembly 6 and are connected to the device cable socket at the proximal end.

[0069] This invention utilizes high-pressure nitrogen or argon throttling cryotherapy as the freezing mode, requiring only vacuum insulation of the flexible catheter segment at the tip, thus optimizing the pressure resistance and local insulation of the tubing and connectors. Simultaneously, a rewarming module and a radiofrequency ablation module are added to the cryoablation probe, enabling central control switching between the three modules. The rewarming module can be used independently with the cryoablation module or as a switching medium between the cryoablation and radiofrequency ablation modules. This module significantly improves the rapid switching from the cryoablation to the radiofrequency module, resulting in a shorter switching time compared to commercially available methods, thus enhancing surgical efficiency. By adding a pressure proportional valve with temperature feedback control, radiofrequency ablation can be achieved at a lower pressure than the cryoablation gas source, while ensuring cooling circulation (gas cooling) for the radiofrequency probe.

[0070] This invention analyzes temperature monitoring and feedback in the ablation module. As the core of this control module, selecting accurate acquisition points and achieving effective closed-loop control from ablation temperature to cooling gas inlet pressure is a key challenge and pain point in this technology. This invention proposes a design scheme based on experimental and multi-test results, analyzing and elaborating on each aspect and optimizing the relevant structure. This scheme significantly improves the performance of temperature feedback control. This invention truly realizes an integrated heating and cooling design on a flexible ablation catheter, fundamentally solving the shortcomings of single ablation modes, truly achieving multi-functional use and flexibility of a single gas source, and improving the convenience and safety of surgery.

[0071] Specifically, the needle guide portion 1 is provided with a JT groove 102, a rewarming wire 104, a thermocouple 105, and an inner wall tube 106. The distal end of the needle guide portion 1 is a metal needle shell 101, and the proximal end is a non-metallic flexible outer wall tube 103. For ease of processing and assembly, it can be disassembled into two main components. The needle shell 101 is divided into a needle shell end cap 1011 and a needle shell connector 1012. The inner wall tube 106 is fixed to the inner wall of the needle shell connector 1012. The connector and the inner wall tube 106 are fixed by adhesive. The proximal end of the needle shell connector 1012 is riveted to wrap around the outer wall tube 103 and form a vacuum layer 107 in the middle. The JT groove 102 and various signal transmission lines form a whole that passes through the inner wall tube 106 and reaches the interior of the distal needle shell 101.

[0072] In this invention, the electrical transmission signal line includes a temperature recovery signal line, a temperature measurement signal line, and a radio frequency signal line. The temperature recovery signal line is implemented by a temperature recovery wire 104, which is typically fixed to the JT slot 102 and used as a whole with the JT slot 102. The temperature measurement signal line is implemented by a temperature measuring thermocouple 105. It is known that... Figures 11-12 It can be seen that two methods can be used: fixing it on the JT slot 102 or fixing it inside the top of the needle housing 101; the radio frequency signal line can be implemented by either the radio frequency connection line 108 or the JT slot 102 itself as the conductor.

[0073] like Figure 6c The proximal end of the needle blade housing connector 1012 shown has a two-layer structure. This structure can be completed by welding the early gradient tube and the inner tube to form an integral part. In order to facilitate the assembly of the vacuum wall structure, the outer wall tube 103 is fixed in the sandwich of the two-layer structure of the needle blade housing connector 1012.

[0074] The needle housing 101 is typically connected to the needle housing connector 1012 and the needle housing end cap 1011 using laser welding. The proximal end of the vacuum layer 107 is connected to the vacuum plug 501 via a three-way connection and a vacuum conduit extension tube. Since an RF cable is needed to enhance the RF ablation function, this invention achieves this function by connecting the RF cable to the proximal air inlet extension tube 302 of the JT slot 102 or by directly connecting the RF cable to the distal needle housing 101.

[0075] Specifically, the handle 2 includes a handle housing 201, a handle bend protector 202, a handle fixing member 203, and a three-way structure. The handle housing 201 provides support. The handle bend protector 202 connects to the handle housing 201 and provides bend protection for the proximal portion of the needle guide tube 1, preventing stress bending and damage to the product during use. The handle fixing member 203 connects to the proximal guide tube extension tube 301, with its distal end connected to the handle housing 201 for overall product connection and fixation. The three-way structure is designed to be placed inside the handle housing 201. This structure is designed to provide isolation between the inlet / outlet air and the vacuum layer 107, preventing the vacuum layer 107 from failing due to inlet / outlet air mixing into it. The three-way structure can be machined or injection molded from metal, and can be fixed by gluing or welding. The specific structure of the three-way structure is not shown in this invention; adjustments can be made according to space and structural requirements during use. However, the design concept of the three-way structure in this invention falls within the scope of protection of this invention.

[0076] Figures 14a-14b This image is for reference. Figure 11 and Figure 13 The internal structure of the specific implementation scheme is shown. In this scheme, the JT groove 102 is fixed to the inner wall of the needle blade housing 101 by welding. See details... Figure 14b That is, the JT groove 102 is fixed to the needle cutter housing connector 1012 of the needle cutter housing 101 by welding. The welding point is the welding point 109 between the needle cutter housing and the JT groove. Laser welding is recommended. The JT groove 102 is located inside the catheter as follows: Figure 14a As shown in the figure, the end of the needle blade 102 is suspended inside the needle blade housing 101. The rewarming wire 104 and the thermocouple 105 are fixed together at the distal end of the JT groove 102, typically by soldering. The presence of the solder joint allows the JT groove 102 to be conductive with the needle blade housing 101, thus enabling it to be used as part of the radio frequency (RF) signal transmission line. Simply connecting the RF cable 603 to the inlet extension tube 302 at the near end of the device satisfies the RF function requirements. This design maximizes the use of the existing cryoablation structure, ensuring that cold air smoothly enters the target area during cryoablation and RF ablation, preserving the full functionality.

[0077] Figures 15a-15b This image is for reference. Figure 11 and Figure 13 The internal structure of the specific implementation scheme shown. Compared to Figure 14a and Figure 14bUnlike other solutions, this one moves the fixed position of the thermocouple 105 wire from the JT groove 102 to the inside top of the needle housing 101, specifically inside the groove of the needle housing head 1011. This solution requires pre-soldering the thermocouple wire to the needle housing head 1011; the soldering point is the soldering point 110 between the needle housing and the thermocouple wire. The remaining structure is the same as... Figure 14a and Figure 14b Maintaining consistency. The advantage of this structure is that it can effectively monitor the highest energy position of radiofrequency ablation in the target area of ​​the ablation catheter, and temperature monitoring is more intuitive and effective. However, the disadvantage is that the process is complicated, requiring both laser welding and soldering of the welding points.

[0078] Figures 16a-16b This image is for reference. Figure 11 and Figure 13 The internal structure of the specific implementation scheme shown. (Known) Figures 14a-14b and Figures 15a-15b All of these are proximal fixation schemes for the JT groove 102. Based on this, we designed a scheme in which the distal end of the JT groove 102 can be fixed in the inner cavity of the needle housing 101, as follows: Figure 16b As shown. The advantage of this solution is that the JT groove 102 and the temperature measuring thermocouple 105 can be fixed as a whole in the inner cavity of the needle blade housing 101, with the whole as a welding point. Soldering is recommended, which eliminates the process of adding welding points due to welding fixation at the near end, reducing unnecessary processing steps and reducing the processing difficulty of laser welding. At the same time, since the top hole of the JT groove 102 has been welded closed to form the welding point 109 between the needle blade housing and the JT groove, multiple rows of JT groove side holes 1021 have been added to its far side to ensure smooth air intake of the JT groove 102.

[0079] Figures 17a-17b This image is for reference. Figure 11 and Figure 13 The internal structure of the specific implementation scheme is shown. This design directly introduces an RF connection line 108 to replace the function of the original JT slot 102 conducting RF cable 603. The RF connection line 108 and the temperature measuring thermocouple 105 are integrally soldered to the inner top of the needle blade housing head 1011. Soldering is recommended. The advantage of this design is that since the RF connection line 108 is already connected to the needle blade housing 101 as an energy source, it is no longer necessary to conduct through the JT slot 102 to the needle blade housing 101. This design eliminates the dependence on the RF conduction of the JT slot 102. Furthermore, the JT slot 102 no longer needs to be assembled by far-end or near-end soldering. Only the temperature measuring thermocouple 105 and the RF connection line 108 are soldered to the inside of the needle blade housing head 1011. The soldering point is [not specified]. This makes the structure of the present invention more convenient to process and assemble the JT slot 102 structure.

[0080] Specifically, the conduit extension tube assembly 3 includes a conduit extension tube outer tube 301, an inlet tube extension tube 302, a return tube extension tube 303, a vacuum extension tube 304, a rewarming wire extension tube 305, and a thermocouple extension tube 306. The distal end of the inlet tube extension tube 302 is directly connected to the JT groove 102. The distal end of the return tube extension tube 303 is directly connected to the inner wall tube 106 through one port of the tee structure inside the handle 2. The vacuum extension tube 304 is connected to the vacuum layer 107 through the other port of the tee structure. The distal end of the rewarming wire extension tube 305 is directly connected to the rewarming wire 104. The distal end of the thermocouple extension tube 306 is directly connected to the thermocouple 105. The radio frequency cable 603 can be fixed to the outer wall of the proximal end of the inlet tube extension tube 302 by soldering, or the radio frequency cable 603 can be directly connected to the top of the distal needle tip shell.

[0081] Specifically, the plug assembly 4 includes a quick-connect plug 401, an upper plug handle 402, and a lower plug handle 403. The quick-connect plug 401 is assembled with the upper plug handle 402 and the lower plug handle 403 via a snap-fit ​​structure. The quick-connect plug 401 directly mates with a socket on the device. The plug assembly 4 must meet the requirements for cryo-RF ablation plugging / unplugging, vacuum plugging / unplugging, and cable plugging / unplugging functions.

[0082] Specifically, the cable plug assembly 6 includes a cable plug 601 and a cable plug extension tube 602. The cable plug extension tube 602 contains a rewarming wire extension line 305, a thermocouple extension line 306, and a radio frequency cable 603, which respectively transmit rewarming electric heating signals, temperature signals, and radio frequency transmission signals. The device can monitor the temperature signal during the ablation procedure in real time and adjust the pressure through temperature signal feedback control. (See details...) Figure 1 and Figure 3 The RF cable 603 is used to transmit RF signals and perform RF ablation. To meet basic functional requirements, the cable plug 601 should be selected with at least 6 cores (including 6 cores).

[0083] Specifically, the vacuum plug assembly 5 is a vacuum plug 501. Two openings are reserved on the lower 403 of the plug handle. The two openings on the lower 403 of the plug handle can pass through the vacuum extension tube 304 and the cable plug extension tube 602 respectively and connect to the vacuum plug 501 and the cable plug 601 to form the vacuum plug assembly 5 and the cable plug assembly 6.

[0084] Reference Figures 11-12 As shown: Schematic diagram of different temperature monitoring points when the cryoradioablation catheter is activated. Figure 11As shown, as one of the core components of the control module, the product of this invention needs to effectively monitor and control the temperature. Therefore, selecting an accurate acquisition point and completing effective closed-loop control from the ablation temperature to the cooling gas inlet pressure is the core focus of this invention. It is known that a T-type thermocouple is generally recommended for temperature measurement. The specifications of the temperature-measuring thermocouple 105 can be selected according to the specific specifications of the ablation catheter to ensure proper assembly and accurate monitoring. It is known that both external and internal detection can be used during product installation. However, due to the limitations of surgery, the ablation catheter cannot detect surrounding tissue or add a temperature sensor to the outer surface of the bare needle to provide real-time ablation temperature feedback. Therefore, this invention, combining its own design and the basic characteristics of the flexible cryo-radiofrequency ablation catheter, preferably places the temperature monitoring point inside the needle housing 101 at the top. Figure 11 As shown in point A, or by placing the temperature monitoring point on JT tank 102, as shown in point A. Figure 11 As shown at point B, and based on data from different monitoring locations, a schematic diagram of temperature curves at different monitoring points was obtained when the cryoablation catheter was activated for radiofrequency treatment, as shown in the figure. Figure 12 As shown in the diagram, the known data indicates that under the same conditions, the thermal ablation temperature at point A is higher than that at point B. This is due to the fundamental properties of radiofrequency ablation; the tip of the needle housing 101 is the energy concentration zone for radiofrequency ablation. However, both exhibit consistent trends: they reach their highest temperatures at the same time, and their upward and downward trends are essentially the same. Therefore, we can introduce a cooling function to control the temperature rise, slowing down or suppressing the temperature within a controllable range, thereby achieving effective cooling of the thermal ablation process.

[0085] A cryoradiofrequency ablation catheter system includes a cryoradiofrequency ablation catheter, a cryoablation module, a radiofrequency ablation module, a rewarming module, and a control center. Each module can be freely switched through the control center, thus satisfying both combined use and individual use. Medical staff can select the appropriate surgical plan according to actual needs. High-pressure gas is used as the gas source, and the distal flexible catheter has a double-layer catheter structure with a vacuum insulation function in the middle layer.

[0086] The gas source is controlled and regulated via a solenoid valve. The distal flexible conduit has a double-layer structure with a middle layer providing vacuum insulation, effectively improving freezing efficiency and isolating the cold source. This vacuum function remains active during the switching between the three modules. In the cryoablation module, a pressure proportional solenoid valve with temperature control is incorporated. This function allows for temperature-based regulation and ensures stable control of the radiofrequency ablation module. While traditional radiofrequency ablation may employ water or air cooling, this system design utilizes a single gas source, simplifying the system structure and improving the utilization of both the gas and cold sources.

[0087] Specifically, the schematic diagram of the cryoablation module is as follows Figure 2 As shown, a pressure proportional solenoid valve with temperature control function adjustment is introduced in the cryoablation module. The air source is input into the air pressure P1 through the solenoid valve II, and becomes P2 after passing through the flow proportional valve, and then reaches the probe head end through the precooling device for cryoablation.

[0088] Specifically, the schematic diagram of the radiofrequency ablation module is as follows Figure 3 As shown, the radiofrequency ablation module includes a radiofrequency emitting device and a probe. The radiofrequency emitting device generates radiofrequency energy at the probe head, causing a local temperature increase in the tissue to achieve thermal ablation. If the temperature continues to rise, it will inevitably cause risks such as tissue damage or carbonization due to excessive temperature. Therefore, a detector is connected to the outside of the probe head and a temperature control structure is connected to the system to detect and feedback real-time temperature signals. At this time, the original cryoablation module becomes a cooling function module to balance the radiofrequency energy. When this function is used, the air pressure input from the air source is still P2 after passing through the solenoid valve II, and the air pressure is adjusted to P3 after passing through the pressure proportional valve. It is known that P3 < P2, and the pressure output of P3 needs to be controlled and adjusted by receiving the feedback temperature signal T2, which can meet the dynamic adjustment function and finally achieve a stable balance under the radiofrequency function module.

[0089] The schematic diagram of the rewarming module is as follows Figure 4 As shown, when the control center activates the rewarming module, the cryo module and the rewarming module stop. At this time, it mainly helps the tissue to quickly rewarm after the cryo module ends. This function can be used in conjunction with cryoablation. At the same time, we know that after freezing the tissue first, it is difficult to reach the radiofrequency ablation conditions (such as too high impedance value) in a short time and the tissue needs to be thawed as soon as possible. Therefore, the use of this function can help shorten the time from cryoablation to radiofrequency ablation and improve the surgical efficiency.

[0090] It should be noted that the fixing method of the catheter and the connector can be adhesive bonding, press riveting or laser welding.

[0091] The gas in the gas cylinder can be high-pressure nitrogen, argon or nitrogen-argon mixture.

[0092] The above are only the embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, various changes and modifications can be made to the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the scope of the claims of the present invention.

Claims

1. A cryoradiofrequency ablation catheter, characterized in that, The device includes a needle guide portion (1), a handle (2), a guide tube extension assembly (3), a plug assembly (4), a vacuum plug assembly (5), and a cable plug assembly (6); the needle guide portion (1) is flexible; the proximal end of the guide tube extension assembly (3) is connected to the distal end of the needle guide portion (1) for hand-held use by the user, the distal end of the guide tube extension assembly (3) is connected to the handle (2), and the proximal end of the plug assembly (4) is connected to the plug assembly (4); the distal end of the plug assembly (4) is connected to the device socket portion of the guide tube extension assembly (3) to realize product insertion, removal, and fixation; the distal end of the vacuum plug assembly (5) is connected to the plug assembly (4) and extends into the vacuum layer (107) of the needle guide portion (1), and the proximal end is connected to the device vacuum socket position; the distal end of the cable plug assembly (6) is connected to the plug assembly and extends into the needle guide portion (1).

2. The cryoradiofrequency ablation catheter according to claim 1, characterized in that: The needle conduit part (1) is provided with a JT groove (102), a rewarming wire (104), a thermocouple (105), and an inner wall tube (106) inside. The distal end of the needle conduit part (1) is a metal needle blade shell (101), and the proximal end is a non-metallic flexible conduit outer wall tube (103). The needle blade shell (101) is divided into a needle blade shell end cap (1011) and a needle blade shell connector (1012). The inner wall tube (106) is fixed to the inner wall of the needle blade shell connector (1012). The outer wall tube (103) is fixed in the double-layer structure of the needle blade shell connector (1012) to form a vacuum layer (107) in the middle layer. The JT groove (102) and various signal transmission lines form a whole and pass through the inner wall tube (106) to the interior of the distal needle blade shell (101).

3. The cryoradiofrequency ablation catheter according to claim 2, characterized in that: The handle (2) includes a handle housing (201), a handle bend protector (202), a handle fixing member (203), and a three-way structure. The handle housing (201) provides support. The handle bend protector (202) is connected to the handle housing (201) and provides bend protection and support to the proximal part of the needle guide tube (1). The handle fixing member (203) is connected to the proximal guide tube extension tube outer tube (301) and the distal end is connected to the handle housing (201) for overall product connection and fixation. The three-way structure is designed to be placed inside the handle housing (201).

4. The cryoradiofrequency ablation catheter according to claim 3, characterized in that: The conduit extension tube assembly (3) includes an outer conduit extension tube (301), an inlet extension tube (302), a return extension tube (303), a vacuum extension tube (304), a rewarming line extension tube (305), and a thermocouple extension tube (306). The distal end of the inlet extension tube (302) is directly connected to the JT groove (102). The distal end of the return extension tube (303) is directly connected to the inner wall tube (106) through one port of the three-way structure inside the handle (2). The vacuum extension tube (304) is connected to the vacuum layer (107) through the other port of the three-way structure. The distal end of the rewarming line extension tube (305) is directly connected to the rewarming line (104). The distal end of the thermocouple extension tube (306) is directly connected to the thermocouple (105).

5. The cryoradiofrequency ablation catheter according to claim 4, characterized in that: The plug component (4) includes a quick plug (401), an upper plug handle (402), and a lower plug handle (403). The quick plug (401) is assembled with the upper plug handle (402) and the lower plug handle (403) through a snap structure, and the quick plug (401) is directly used in cooperation with a socket on the device.

6. The cryoradiofrequency ablation catheter according to claim 5, characterized in that: The cable plug component (6) includes a cable plug (601) and a cable plug extension tube (602). Inside the cable plug extension tube (602), there are a rewarming wire extension (305), a temperature measuring thermocouple extension (306), and a radio frequency cable (603), which respectively transmit rewarming electric heating signals, temperature signals, and radio frequency transmission signals.

7. The cryoradiofrequency ablation catheter according to claim 6, characterized in that: The vacuum plug component (5) is a vacuum plug (501). Two openings are reserved on the lower plug handle (403). The two openings reserved on the lower plug handle (403) can respectively pass through a vacuum extension tube (304) and a cable plug extension tube (602) and are connected to the vacuum plug (501) and the cable plug (601) to form the vacuum plug component (5) and the cable plug component (6).

8. A cryoradiofrequency ablation catheter system, characterized in that: It includes the cryo radiofrequency ablation catheter according to any one of claims 1-7, and further includes a cryoablation module, a radiofrequency ablation module, a rewarming module, and a control center. Each module can be freely switched through the control center; high-pressure gas is used as the gas source, and the distal flexible catheter has a double-layer catheter structure, and the middle interlayer has a vacuum insulation function.

9. A cryoradiofrequency ablation catheter and system according to claim 8, characterized in that: A pressure proportional solenoid valve with temperature control function adjustment is introduced into the cryoablation module. The gas source is input into the solenoid valve II with a pressure of P1, and after passing through the flow proportional valve, it is P2, and after passing through the precooling device, it reaches the probe head end for cryoablation.

10. A cryoradiofrequency ablation catheter and system according to claim 9, characterized in that: The radiofrequency ablation module includes a radiofrequency transmitting device and a probe. The radiofrequency transmitting device generates radiofrequency energy at the probe head. A detector is connected to the outside of the probe head, and the system is connected to a temperature control structure; the original cryoablation module becomes a cooling function module. The gas source input pressure is P2 after passing through the solenoid valve II, and is adjusted to P3 after passing through the pressure proportional valve, where P3 < P2 and is controlled and adjusted by the feedback temperature signal T2.

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