Cryoablation System

Abstract

The cryoablation system of the present application includes first, second, and third pressure vessels and a cryoablation device; a first pipeline for supplying liquid working fluid is connected between the first pressure vessel and the cryoablation device; a second pipeline and an eighth pipeline for reflux liquid working fluid during pre-cooling are connected between the second pressure vessel and the first pipeline, and a fourth pipeline for outputting pressure to the first pressure vessel is connected between the second pressure vessel and the first pressure vessel; the third pressure vessel is unidirectionally connected to the first pressure vessel and is connected to the second pressure vessel through a fifth pipeline to provide gaseous working fluid; a seventh pipeline for recovering the working fluid passing through the cryoablation device is connected between the second pressure vessel and the cryoablation device, and the seventh pipeline is connected to the second pressure vessel through the eighth pipeline after intersecting with the second pipeline; the second pressure vessel is connected to the cryoablation device through the sixth pipeline, thereby improving safety of use and reducing working fluid consumption.

Description

Technical Field

[0001] The present application relates to the field of medical device technology, and in particular to a cryoablation system. Background Art

[0002] In the fight against cancer, chemotherapy, radiotherapy, and surgery have become the three main treatments for malignant tumors, with tumor immunotherapy also being actively researched. Minimally invasive tumor treatments are an important complement to surgical interventions, with physical ablation, including microwaves, cryosurgery, lasers, radiofrequency, and high-power focused ultrasound, increasingly being used to induce necrosis of cancerous tissue.

[0003] In the early 20th century, industry and technology advanced rapidly. Advances in industrial technology led to the successful production of refrigerants such as concentrated oxygen, liquid oxygen, concentrated nitrogen, liquid nitrogen, and dry ice. This not only accelerated commercial development but also opened up new avenues for medical refrigeration, advancing the application of cryogenic technology in healthcare. A variety of refrigeration technologies emerged in response to the continuous advancement of cryogenic science. Gas throttling, phase change cooling, vapor pressure absorption refrigeration, and thermoelectric refrigeration are the main refrigeration solutions used in modern medicine.

[0004] The existing cryoablation systems mainly have the following problems:

[0005] 1) The operating pressure of the existing high-pressure cryoablation system is too high, posing a safety hazard.

[0006] 2) During the transmission process of the existing low-pressure cryoablation system, after the liquid phase changes to the gas phase, the volume expands rapidly, causing "gas blockage", which creates flow resistance and hinders the forward flow of the liquid phase.

[0007] 3) The cryoablation range of the system is unstable, making it difficult to achieve consistent ablation effects.

[0008] 4) In some low-temperature ablation systems that use liquid nitrogen as a working fluid, it is necessary to heat the liquid nitrogen to generate nitrogen gas as a reheating working fluid. However, the vaporization of liquid nitrogen when heated will cause the pressure in the container to rise rapidly, which is difficult to control and poses a great safety risk. Summary of the Invention

[0009] The present application discloses a cryoablation system, which can improve the safety of use, reduce the consumption of working fluid, etc.

[0010] A cryoablation system of the present application includes a first pressure vessel, a second pressure vessel, a third pressure vessel, and a cryoablation device;

[0011] A first pipeline for supplying liquid working medium is connected between the first pressure container and the cryoablation device;

[0012] A second pipeline and an eighth pipeline for reflux of liquid working medium during pre-cooling are connected between the second pressure vessel and the first pipeline, and a fourth pipeline for outputting pressure to the first pressure vessel is connected between the second pressure vessel and the first pressure vessel;

[0013] The third pressure vessel is in one-way communication with the first pressure vessel and is connected to the second pressure vessel through a fifth pipeline to provide a gaseous working medium;

[0014] A seventh pipeline for recovering the working fluid passing through the cryoablation device is connected between the second pressure vessel and the cryoablation device, and the seventh pipeline intersects with the second pipeline and then connects to the second pressure vessel through an eighth pipeline;

[0015] The second pressure vessel is connected to the cryoablation device through a sixth pipeline, and is used to output the heated gaseous working medium to the cryoablation device during rewarming.

[0016] Several optional methods are also provided below, but they are not intended to be additional limitations on the above-mentioned overall solution. They are merely further supplements or optimizations. Under the premise that there are no technical or logical contradictions, each optional method can be combined separately for the above-mentioned overall solution, or multiple optional methods can be combined.

[0017] Optionally, the first pressure vessel is equipped with a first pressure sensor for obtaining a first current pressure;

[0018] The controlled elements on the fourth pipeline are a fourth pressure control element and a fourth solenoid valve connected in series in sequence between the second pressure vessel and the first pressure vessel;

[0019] The fourth solenoid valve opens when the first current pressure reaches a first preset pressure value, connecting the second pressure container and the first pressure container, and the fourth pressure control element automatically controls its own output pressure to be lower than its own input pressure.

[0020] Optionally, the second pressure vessel is provided with a second pressure sensor for obtaining a second current pressure;

[0021] The controlled elements on the fifth pipeline are a fifth solenoid valve and a fifth pressure control element which are sequentially connected in series between the third pressure vessel and the second pressure vessel;

[0022] The fifth solenoid valve opens when the second current pressure is lower than the second pressure preset value, connecting the third pressure container and the second pressure container, and the fifth pressure control element automatically controls its own output pressure to be lower than its own input pressure.

[0023] Optionally, the fifth pipeline is provided with a third pressure sensor for monitoring a third pressure vessel to obtain a third current pressure;

[0024] The third pressure vessel is provided with a heating device for heating the liquid working medium in the third pressure vessel to change the phase into gaseous working medium and increase the third current pressure;

[0025] When the third current pressure reaches a third preset pressure value, the heating device stops heating.

[0026] Optionally, the sixth pipeline includes:

[0027] a replacement and rewarming tube, one end of which is connected to the second pressure vessel and the other end of which is connected to the cryoablation device and is capable of transporting the gaseous working medium in the second pressure vessel to the cryoablation device;

[0028] A replacement and rewarming solenoid valve is provided on the replacement and rewarming pipe to control the on and off of the replacement and rewarming pipe;

[0029] a replacement and rewarming heat exchanger, used for heating the gas working medium in the replacement and rewarming tube;

[0030] A replacement and rewarming one-way valve is provided on the replacement and rewarming pipe to limit backflow.

[0031] Optionally, a heating component is provided in the cryoablation device, and a rewarming temperature sensor is provided on the downstream side of the replacement and rewarming heat exchanger, and the rewarming temperature sensor controls the replacement and rewarming heat exchanger accordingly;

[0032] The second pressure sensor and the rewarming temperature sensor together participate in controlling the heating component.

[0033] Optionally, the seventh pipeline includes:

[0034] a gas return pipe, one end of which is connected to the outlet of the cryoablation device and the other end of which is connected to the eighth pipe;

[0035] The seventh pipeline one-way valve is arranged on the return air recovery pipe to limit backflow.

[0036] Optionally, the eighth pipeline includes:

[0037] A system flow monitoring and recovery condition control pipe, one end of which is connected to the return air recovery pipe and the other end of which is connected to the second pressure vessel;

[0038] A system flow monitoring and recovery condition extraction booster pump is provided on the system flow monitoring and recovery condition control pipe;

[0039] The system flow monitoring and recovery condition one-way valve is arranged on the system flow monitoring and recovery condition control pipe to limit backflow.

[0040] Optionally, the eighth pipeline further includes:

[0041] a system flow monitoring and recovery condition control heat exchanger, located upstream of the system flow monitoring and recovery condition extraction booster pump and thermally coupled to the system flow monitoring and recovery condition control pipe;

[0042] The system flow monitoring and recovery condition control temperature sensor collects the fluid temperature in the system flow monitoring and recovery condition control pipe and is used to control the system flow monitoring and recovery condition control heat exchanger accordingly.

[0043] Optionally, a system flow monitoring and recovery condition control flow meter is configured on the upstream side of the system flow monitoring and recovery condition extraction booster pump.

[0044] The three pressure vessels in the cryoablation system provided in the present application perform pressure compensation with each other, providing a stable pressure output environment during cryoablation, and can recycle the working fluid for recycling, thereby reducing the consumption of the working fluid. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 A schematic diagram of the cryoablation system of this application (part of which is a schematic diagram of the rewarming system);

[0046] Figure 2 Schematic diagram of the liquid refrigerant tube-in-tube structure;

[0047] Figure 3 This is a structural diagram of a liquid refrigerant pipe gas-liquid separation device;

[0048] Figure 4 This is a schematic diagram of the structure of the liquid refrigerant output valve;

[0049] Figure 5 Schematic diagram of the liquid refrigerant tube structure;

[0050] Figure 6 Schematic diagram of the phase change pressure vessel structure;

[0051] Figure 7A 、 Figure 7B Schematic diagrams of the structures of two embodiments of a one-way flow device for liquid working medium;

[0052] Figure 8 It is a structural diagram of a one-way flow device for liquid working medium;

[0053] Figure 9 A schematic diagram of the structure of a computer device;

[0054] Figures 10 to 15 This is a method flow chart. The connection relationship between the various figures can be seen from the corresponding labels at the boundary parts. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0056] 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 an intermediate 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 an intermediate component.

[0057] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0058] See Figure 1 The present application provides a rewarming system for cryoablation, comprising a gaseous working medium pressure vessel (C2) and a replacement and rewarming pipeline (L6), wherein the replacement and rewarming pipeline (L6) is used to connect the gaseous working medium pressure vessel (C2) and the cryoablation device; the replacement and rewarming pipeline (L6) includes:

[0059] a replacement and rewarming tube (L6-1), one end of which is connected to the gaseous working medium pressure vessel (C2) and the other end of which is connected to the cryoablation device and is capable of transporting the gaseous working medium in the gaseous working medium pressure vessel to the cryoablation device (CP);

[0060] The displacement and rewarming solenoid valve (L6-2) is provided on the displacement and rewarming pipe (L6-1) to control the on-off of the displacement and rewarming pipe (L6-1);

[0061] The displacement and rewarming heat exchanger (L6-3) is used to heat the gas working medium in the displacement and rewarming pipe (L6-1);

[0062] The displacement and rewarming one-way valve (L6-5) is installed on the displacement and rewarming pipe (L6-1) to limit backflow.

[0063] A rewarming temperature sensor (L6-4) is provided on the downstream side of the replacement and rewarming heat exchanger to control the replacement and rewarming heat exchanger (L6-3) accordingly.

[0064] In this embodiment, the replacement and rewarming pipe (L6), its replacement and rewarming heat exchanger (L6-3) can heat the fluid working medium passing through the replacement and rewarming pipe (L6-1), and the rewarming temperature sensor (L6-4) monitors whether the fluid working medium in the replacement and rewarming pipe (L6-1) reaches the threshold temperature; the opening and closing of the replacement and rewarming solenoid valve (L6-2) controls the fluid working medium in the gaseous working medium pressure vessel (C2) to enter the replacement and rewarming pipe (L6-1); the replacement and rewarming one-way valve (L6-5) prevents the backflow of fluid into the cryoablation device (CP). During the rewarming process of a cryoablation procedure, the displacement and rewarming heat exchanger (L6-3) heats the fluid entering the displacement and rewarming tube (L6-1) to a rewarming temperature. The rewarming temperature is greater than the lower rewarming threshold and less than the upper rewarming threshold. The temperature detected by the rewarming temperature sensor (L6-4) during the rewarming process participates in closed-loop control, adjusting the heating power of the rewarming heat exchanger (L6-3) to ensure that the detected rewarming temperature satisfies the following conditions: the lower rewarming threshold < the rewarming temperature < the upper rewarming threshold. During the displacement process of a cryoablation procedure, the rewarming heat exchanger (L6-3) does not operate, and the fluid entering the displacement and rewarming tube (L6-1) is not heated during this process. Furthermore, a heating component (heatable nickel-chromium wire) is provided at the distal end of the cryoablation device (CP) to facilitate the rewarming process during the cryoablation procedure.

[0065] The gaseous working fluid pressure vessel (C2) contains a pressure sensor C2-1, and the cryoablation device CP contains a temperature sensor. The output of the rewarming nitrogen gas during rewarming is calculated based on the pressure detected by the pressure sensor. The rewarming heat output is then calculated based on the nitrogen gas temperature measured by the temperature sensor. The heat output is then controlled based on the real-time calculated heat output efficiency to maintain a constant heat output during rewarming. This embodiment combines rewarming nitrogen gas with heating of the nickel-chromium wire. By monitoring the temperature and pressure within the device, the nickel-chromium wire heating is adjusted to compensate for any instability in the rewarming gas. This achieves stable and efficient rewarming, reducing surgical time and improving surgical outcomes.

[0066] The rewarming system also includes an interconnected return air recovery pipeline (L7) and a system flow monitoring and recovery condition control pipeline (L8), one end of the return air recovery pipeline (L7) is connected to the outlet of the cryoablation equipment, and one end of the system flow monitoring and recovery condition control pipeline (L8) is connected to the gaseous working fluid pressure vessel (C2).

[0067] Among them, the return air recovery pipeline (L7) includes a return air recovery pipe (L7-1), one end of the return air recovery pipe (L7-1) is connected to the outlet of the cryoablation equipment, and the other end is connected to the system flow monitoring and recovery condition control pipeline (L8); a one-way valve (L7-2) for limiting backflow is provided on the return air recovery pipe (L7-1).

[0068] The system flow monitoring and recovery condition control pipeline (L8) includes a system flow monitoring and recovery condition control pipe (L8-1), one end of which is connected to the return gas recovery pipe (L7-1), and the other end is connected to the gaseous working medium pressure vessel (C2). A system flow monitoring and recovery condition extraction booster pump (L8-5) and a system flow monitoring and recovery condition one-way valve (L8-6) for limiting backflow are also provided on the system flow monitoring and recovery condition control pipe (L8-1).

[0069] The system flow monitoring and recycling condition control pipeline (L8) also includes:

[0070] The system flow monitoring and recovery condition control heat exchanger (L8-2) is located on the upstream side of the system flow monitoring and recovery condition extraction booster pump (L8-5) and is thermally coupled with the system flow monitoring and recovery condition control pipe (L8-1);

[0071] The system flow monitoring and recovery condition control temperature sensor (L8-3) collects the fluid temperature in the system flow monitoring and recovery condition control pipe (L8-1) and is used to control the system flow monitoring and recovery condition control heat exchanger (L8-2) accordingly.

[0072] Combine Figure 1The present application provides a working fluid pre-cooling system for cryoablation, comprising a first pressure vessel (i.e., a liquid working fluid pressure vessel C1), a second pressure vessel (i.e., a gaseous working fluid pressure vessel C2), a first pipeline (i.e., a liquid refrigerant output pipeline L1), and a second pipeline (i.e., a pre-cooling fluid recovery pipeline L2). The first pressure vessel is used to store liquid-phase refrigerant, the second pressure vessel is used to store gaseous working fluid, and the second pipeline is connected between the first and second pressure vessels. The first pipeline is connected between the first pressure vessel and the cryoablation device (CP) to deliver liquid-phase refrigerant to the cryoablation device during the ablation process. The first pipeline has an inner and outer double-layer structure. During pre-cooling, the liquid-phase refrigerant flows from the first pressure vessel, sequentially through the inner layer of the first pipeline (i.e., the inlet channel L1-1-3), the outer layer of the first pipeline (i.e., the return channel L1-1-2), the second pipeline, and finally to the second pressure vessel. As can be seen, one end of the second pipeline is connected to the outer layer of the first pipeline, allowing the working fluid to cool the entire inner layer of the first pipeline before flowing to the second pressure vessel for recovery. The cooling method of the pre-cooling system of the present application is to rely on liquid cryogenic working fluid to cool the inner layer, outer layer, etc. that it passes through, and the pre-cooling can be stopped until the temperature of at least the inner layer meets the preset conditions. When performing cryoablation, the temperature difference between the inner layer and the working fluid is reduced or equal to 0 compared with the existing cryoablation technology during the process of the corresponding working fluid being output from the inner layer to the cryoablation device, which greatly reduces the vaporization amount of the liquid cryogenic working fluid, eliminates the gas blockage phenomenon, and improves the stability and safety of the operation. In addition, the working fluid in the outer layer can form an isolation layer to block the heat exchange between the inner layer working fluid and the air outside the first pipe, thereby extending the time of the cryoablation operation.

[0073] It should be noted here that the state change of the working fluid before or after entering the second pressure vessel is not the focus, but the flow path of the working fluid. For example, the working fluid in the pre-cooling process can be recovered to the second pressure vessel for storage, which is environmentally friendly.

[0074] The end of the first pipe adjacent to the first pressure vessel is designated as the first end, and the end adjacent to the cryoablation device is designated as the second end. The inner layer of the first pipe connects to the first pressure vessel at the first end and to the cryoablation device at the second end. The outer layer of the first pipe connects to the second pipe at the first end and to the inner layer of the first pipe at the second end. The isolation layer covers the entire inner layer, further reducing the amount of working fluid vaporized.

[0075] In one embodiment, a first output valve (i.e., liquid refrigerant output valve L1-2) is disposed on the first pipeline. The first output valve has an output channel (L1-2-1) connected to the inner layer and a return channel (L1-2-2) connected to the outer layer. The opening and closing of the first output valve controls the opening and closing of the output channel and the return channel. The liquid refrigerant output valve (L1-2) includes two pairs of input-output channels: a first input-output channel (corresponding to output channel L1-2-1) and a second input-output channel (corresponding to return channel L1-2-2). The first input-output channel communicates with the liquid refrigerant pipe inlet channel (L1-1-3), while the second input-output channel communicates with the liquid refrigerant pipe return channel (L1-1-2). The first input-output channel is used to supply liquid refrigerant, while the second input-output channel is used to pre-cool the valve body of the liquid refrigerant output valve (L1-2). When the liquid refrigerant output valve (L1-2) is in an open state, the fluid in the liquid refrigerant tube inlet channel (L1-1-3) of the liquid refrigerant tube (L1-1) dynamically flows into and out of the first input-output channel.

[0076] In this embodiment, a second solenoid valve (i.e., pre-cooling fluid recovery solenoid valve L2-2) is configured on the second pipeline to control the on / off state of the second pipeline. During the pre-cooling sequence of the cryoablation process, the pre-cooling fluid recovery solenoid valve (L2-2) is in an open state, and the reflux fluid in the liquid refrigerant tube reflux channel (L1-1-2) dynamically flows into and out of the second input-output channel. After the pre-cooling sequence of the cryoablation process is completed, the pre-cooling fluid recovery solenoid valve (L2-2) is in a closed state, and the reflux fluid in the liquid refrigerant tube reflux channel (L1-1-2) stops flowing, and the fluid in the second input-output channel stops flowing.

[0077] In one embodiment, the first pressure vessel is equipped with a first liquid level sensor for obtaining a first current liquid level. When the first current liquid level meets a preset condition, the first output valve is allowed to open, thereby preventing flow interruption during pre-cooling or cryoablation.

[0078] In another embodiment, a first temperature sensor is arranged on the first pipe near the second end to obtain the first current temperature of the inner layer. Preferably, the first current temperature is the temperature of the inner layer at the first end. When the first current temperature meets the preset conditions, the pre-cooling ends and the first output valve and the second solenoid valve are closed.

[0079] In one embodiment, a safety pressure relief valve (L1-3) is disposed on the outer layer of the first pipe. During the pre-cooling process of the cryoablation procedure, the reflux fluid in the liquid cryogen tube reflux channel (L1-1-2) flows dynamically. After the pre-cooling process of the cryoablation procedure is completed, the reflux fluid in the liquid cryogen tube reflux channel (L1-1-2) stops flowing. After the reflux fluid in the liquid cryogen tube reflux channel (L1-1-2) stops flowing, the fluid pressure in this layer should be limited to an operating pressure range. The safety pressure relief valve (L1-3) prevents the pressure in the liquid cryogen tube reflux channel (L1-1-2) from being too high. When the pressure exceeds the threshold pressure of the liquid cryogen tube reflux channel, the safety pressure relief valve (L1-3) opens and releases pressure. When the pressure falls below the threshold pressure of the liquid cryogen tube reflux channel, the safety pressure relief valve (L1-3) closes.

[0080] In another embodiment, during pre-cooling, the liquid-phase cold working medium also enters the cryoablation device from the second end of the inner layer of the first pipe. The working medium pre-cooling system also includes a seventh pipe (i.e., a return air recovery pipe L7). The liquid-phase cold working medium flows from the first pressure vessel, through the inner layer of the first pipe, through the cryoablation device, through the seventh pipe, and finally to the second pressure vessel. The internal piping of the cryoablation device is also cooled to prevent air blockage within the cryoablation device. Similarly, the working medium during the pre-cooling process is recovered to the second pressure vessel.

[0081] In one embodiment, the second pressure vessel is connected to the first pressure vessel via a fourth pipeline (i.e., the cryoablation working pressure boosting pipeline L4). A controlled element is configured on the fourth pipeline. The controlled element switches on and off accordingly under desired conditions to balance the pressures between the first and second pressure vessels. The desired condition is that when the first current pressure in the first pressure vessel falls below a preset value, the fourth pipeline is connected, allowing the gaseous working fluid in the second pressure vessel to flow into the first pressure vessel, maintaining the pressure of the first pressure vessel within the operating pressure range and enabling continuous output of the liquid-phase cryogenic working fluid. The controlled elements are a fourth pressure control element and a fourth solenoid valve, connected in series between the second and first pressure vessels. When the first current pressure reaches the first preset pressure value, the fourth solenoid valve opens, connecting the second and first pressure vessels. The fourth pressure control element automatically controls its output pressure to be lower than its input pressure.

[0082] The seventh and second pipelines are connected to the second pressure vessel via a booster pump (L8-5), which increases the pressure of the working fluid within the seventh and second pipelines before delivering it to the second pressure vessel. This allows the working fluid to circulate. At the end of pre-cooling (when the first current temperature meets a preset condition), the booster pump is delayed in shutting off. This allows the working fluid in the second and seventh pipelines to be recovered before cryoablation. This delayed shutdown can be achieved by setting a system delay within the system.

[0083] The first pipeline is provided with a first one-way valve (L1-6) to prevent backflow of the liquid working medium.

[0084] The present invention's fluid precooling system for cryoablation is a modification of the existing cryoablation system, dividing the first pipeline used to transport the working fluid into an inner and outer layer. This precooling system effectively reduces the amount of working fluid vaporized during the cryoablation process, eliminating air blockage. Furthermore, the working fluid in the outer layer acts as an isolation layer, limiting heat exchange between the working fluid in the inner layer and the air outside the first pipeline. This prolongs the cryoablation period, particularly during cryoablation procedures, and improves stability and safety. Furthermore, a corresponding pipeline for recovering the working fluid is added, contributing to environmental conservation.

[0085] Combine Figures 1 to 6 The present application provides a conveying device for conveying a working fluid from a first pressure vessel (i.e., a liquid working fluid pressure vessel C1) to a cryoablation device (CP). The working fluid is at a low temperature and in a gas-liquid two-phase state during the conveying process. The first pressure vessel is used to store the liquid working fluid and can convey the working fluid through a power device or its own pressure.

[0086] First, the conveying device includes a first pipeline (liquid refrigerant output pipeline L1) and a gas-liquid separation device. The inner and outer layer structures of the first pipeline in the above embodiment can be understood as including an outer tube (L1-1-4) and an isolation sleeve (L1-1-5) in the outer tube. The outer tube and the isolation sleeve constitute the liquid refrigerant tube (L1-1), and the isolation sleeve divides the first pipeline into an inner and outer double-layer structure in the radial direction.

[0087] The gas-liquid separation device is a cylindrical structure housed within an isolation sleeve. The first end of the cylindrical structure is open, while the second end is closed. The interior of the cylindrical structure defines a first channel (i.e., the gas-liquid separation device base tube L1-1-4-2). A second channel is formed between the outer wall of the cylindrical structure and the inner wall of the isolation sleeve. A through hole (i.e., the vent L1-1-4-3) is provided in the sidewall of the cylindrical structure, connecting the first and second channels. Due to the presence of the through hole, some of the working fluid enters the first channel, and the mass flow rate of this two-phase flow is higher than the mass flow rate of the liquid. The gas-liquid two-phase flow that flows through the second channel and does not enter the liquid refrigerant tube (L1-1-4-2) within the gas-liquid separation device base tube has a higher mass flow rate of the liquid than the gas. This reduces the amount of working fluid vaporized in the second channel, lowering the probability of gas blockage during pre-cooling or ablation. Because the second end of the gas-liquid separation device is closed, working fluid entering the first channel flows toward the first end, in the opposite direction of the working fluid flow in the second channel. Combined with further analysis of the flow path of the working fluid in the first path, the flow path of the working fluid is also divided into two paths: the third path passes through the second channel to the cryoablation device or the outer layer; the fourth path passes through the second channel, the through hole, the first channel to the first end of the first channel.

[0088] In this embodiment, the working fluid stored in the first pressure vessel is liquid nitrogen, which reduces the proportion of liquid nitrogen vaporized due to temperature influences, and at the same time separates the nitrogen vaporized due to unavoidable factors such as friction from the liquid nitrogen, avoids gas blockage, and makes the output liquid nitrogen dosage stable and controllable, thereby achieving a stable cryoablation effect.

[0089] A method for reducing gas blockage may be to reduce the temperature difference between the inner layer temperature and the working medium during cryoablation. For example, in another embodiment, the liquid refrigerant tube (L1-1) is a tube-in-tube structure, including at least two or more tube-in-tube structures; it has: a liquid refrigerant tube thermal insulation channel, a liquid refrigerant tube return channel (L1-1-2), a liquid refrigerant tube inlet channel (L1-1-3), and a liquid refrigerant tube gas-liquid separation device (L1-1-4). The three channels, from the outside to the inside, divide the liquid refrigerant tube (L1-1) into a thermal insulation channel (L1-1-1), a return channel (L1-1-2), and an inlet channel (L1-1-3). The thermal insulation channel can be connected to the return channel (L1-1-2) and flow through the same working medium, or it can be disconnected from the return channel (L1-1-2) and the inlet channel (L1-1-3) and flow through other low-temperature working medium, further blocking heat exchange. In other embodiments, heat exchange is blocked by providing an insulation layer on the outer layer.

[0090] The outer wall of the cylindrical structure is provided with a guide groove for forming a second channel. The guide groove connects the first end and the second end, so that the working medium can flow on the guide groove. In order to achieve effective gas-liquid separation, a through hole is provided on the groove wall of the guide groove. Among them, the outer wall of the cylindrical structure is in contact with the inner wall of the isolation sleeve, and the guide groove is a groove structure, so the working medium can only flow through the guide groove, and then the working medium must pass through the through hole, thereby improving the gas-liquid separation efficiency. In the cross section, the second channel is surrounded by the groove wall of the guide groove and the inner wall of the isolation sleeve, wherein the groove wall of the guide groove is arc-shaped and smooth, which reduces the heat generated by friction with the working medium. The through hole is opened at the bottom of the arc, and the shape of the through hole is circular, which is convenient for processing.

[0091] Combine Figure 3 To further improve separation efficiency, methods include spirally winding guide grooves around the outer wall of the cylindrical structure to form a spiral channel, extending the flow path of the working medium. Alternatively, multiple through-holes are arranged along the guide grooves. Each spiral winding of the guide grooves contains 1 to 8 through-holes, and these through-holes are evenly spaced around the circumference of the cylindrical structure.

[0092] In one embodiment, the first end of the isolation sleeve extends beyond the first end of the outer tube. This extended portion serves as a bottom tube and is at least long enough to extend below the liquid level within the first pressure vessel, enabling continuous delivery of liquid working fluid for pre-cooling and ablation. The first end of the outer tube is located outside the first pressure vessel, allowing the working fluid to be delivered from the first end of the inner layer, then flow through the second end and back to the first end of the outer layer, cooling most or all of the inner layer.

[0093] The first end of the cylindrical structure and the first end of the isolation sleeve are axially adjacent to each other. Mutually adjacent means that the first end of the gas-liquid separation device is also below the liquid level in the first pressure vessel. Therefore, when the working fluid is discharged, it directly enters the second channel for gas-liquid separation. The working fluid that enters the first channel can return to the first pressure vessel and be liquefied, achieving local circulation and saving resources.

[0094] Combine Figure 4In one embodiment, an output valve (i.e., liquid refrigerant output valve L1-2) is disposed on the first pipeline. The output valve has an output channel (L1-2-1) connected to the inner layer and a return channel (L1-2-2) connected to the outer layer. The liquid refrigerant output valve (L1-2) includes two pairs of input-output channels, a first input-output channel (corresponding to the output channel) and a second input-output channel (corresponding to the return channel). The first input-output channel is connected to the liquid refrigerant pipe inlet channel (L1-1-3); the second input-output channel is connected to the liquid refrigerant pipe return channel (L1-1-2). When the liquid refrigerant output valve (L1-2) is in an open state, the fluid in the liquid refrigerant pipe inlet channel (L1-1-3) of the liquid refrigerant pipe (L1-1) dynamically flows into and out of the first input-output channel.

[0095] The gas-liquid separation device of the present application can increase the liquid content of the mass flow of the working fluid delivered to the cryoablation equipment, and further reduce the gas blockage phenomenon.

[0096] The above embodiment completes the pre-cooling of the first pipeline. Next, the first pressure vessel C1 and the second pressure vessel C2 need to be pressurized to reach the pressure required for subsequent cryoablation.

[0097] The present application also provides a working fluid pressure vessel system for cryoablation, comprising a first pressure vessel (i.e., a liquid working fluid pressure vessel (C1), a second pressure vessel (i.e., a gaseous working fluid pressure vessel (C2) and a third pressure vessel (i.e., a phase change pressure vessel (C3), wherein the first pressure vessel is used to store liquid working fluid and supply liquid working fluid to the cryoablation device (CP) during the ablation process, and the working fluid will be discharged after passing through the cryoablation device; the second pressure vessel is used to store gaseous working fluid and is controlledly connected to the first pressure vessel through a fourth pipeline (i.e., the cryoablation working pressure control element L4-3), and at the same time receives reflux working fluid from the cryoablation device; the third pressure vessel is arranged in the first pressure vessel for phase-changing the liquid working fluid into a gaseous working fluid; the third pressure vessel is controlledly connected to the first pressure vessel through a one-way flow device to receive the liquid working fluid; the third pressure vessel is also controlledly connected to the second pressure vessel through a fifth pipeline.

[0098] Controlled elements are respectively arranged on the fourth pipeline and the fifth pipeline. Each controlled element and the one-way flow device is opened and closed accordingly under expected conditions, so that the pressures of the first pressure vessel, the second pressure vessel and the third pressure vessel are correlated.

[0099] First, the reflux fluid is the fluid discharged from the cryoablation device, and the second pressure vessel and the cryoablation device can be connected by a pipeline to enable the flow of the reflux fluid. This process is the fluid recovery process. It should be noted that the state change of the fluid during the recovery process is not the key point.

[0100] Secondly, the pressure linkage process between the three pressure vessels involves the working fluid in the third pressure vessel entering the second pressure vessel for pressure compensation, maintaining the second pressure vessel within a preset pressure range; the working fluid in the second pressure vessel entering the first pressure vessel for pressure compensation, maintaining the first pressure vessel within a preset pressure range, and continuously outputting liquid working fluid; the third pressure vessel maintains its own pressure within a preset pressure range by changing the working fluid state. Each of the above pressure vessels corresponds to a preset pressure range. This pressure linkage process uses the existing second pressure vessel as a transition to achieve overall automatic pressure cycle control. The pressure vessel system of this embodiment is mainly used to control the pressures in the liquid working fluid pressure vessel (C1), the gaseous working fluid pressure vessel (C2), the phase change pressure vessel (C3), and the liquid delivery pipeline (L1) to maintain them within the operating pressure range. The operating pressures of the pressure vessels are: phase change pressure vessel (C3) > gaseous working fluid pressure vessel (C2) > liquid working fluid pressure vessel (C1).

[0101] In the following embodiments, liquid nitrogen is used as an example of a liquid working fluid, and the corresponding gaseous working fluid is gaseous nitrogen.

[0102] The first pressure vessel is equipped with a first pressure sensor (i.e., liquid working fluid pressure sensor C1-1) to obtain a first current pressure. The controlled elements on the fourth pipeline are a fourth pressure control element (i.e., cryoablation working pressure control element L4-3) and a fourth solenoid valve (i.e., boost solenoid valve L4-2), connected in series between the second and first pressure vessels. The fourth solenoid valve opens when the first current pressure reaches a preset first pressure value, connecting the second and first pressure vessels. The fourth pressure control element automatically controls its output pressure to be less than its input pressure. The second pressure vessel primarily serves to compensate for the increased pressure within the first pressure vessel. Of course, if the first pressure vessel is overpressured, it also requires pressure relief. In one embodiment, the first pressure vessel is equipped with exhaust and pressure relief pipelines, each equipped with a solenoid valve (i.e., pressure relief solenoid valve L3-2) that opens at a preset pressure to relieve pressure.

[0103] Automatic pressure control for the first pressure vessel:

[0104] The working pressure of the liquid working fluid pressure vessel (C1) is maintained within a desired range through a cryoablation working pressure reducing pipe (L3), a cryoablation working pressure boosting pipe (L4), and a liquid working fluid pressure sensor (C1-1); the liquid working fluid pressure sensor (C1-1) collects a first current pressure of the liquid working fluid pressure vessel (C1), and the first current pressure is used to determine whether the working pressure of the liquid working fluid pressure vessel (C1) is within the desired range.

[0105] The working pressure is the nominal pressure of the liquid working fluid pressure vessel (C1), and the working pressure range is the pressure interval of the liquid working fluid pressure vessel (C1) corresponding to the nominal pressure. The pressure interval takes the working pressure as the median, and there is an upper deviation relative to the median as the upper limit of the pressure interval, and there is a lower deviation relative to the median as the lower limit of the pressure interval. Different working pressures of the liquid working fluid pressure vessel (C1) correspond to their corresponding pressure intervals, that is, the working pressure range.

[0106] When the pressure collected by the liquid working fluid pressure sensor (C1-1) drops to a first boost opening threshold, the cryoablation working pressure boost solenoid valve (L4-2) in the cryoablation working pressure boost pipeline (L4) opens, and the gaseous working fluid in the gaseous working fluid pressure vessel (C2) enters the liquid working fluid pressure vessel (C1) through the cryoablation working pressure boost pipe (L4-1) for boosting; when the pressure collected by the liquid working fluid pressure sensor (C1-1) is higher than a first boost closing threshold, the cryoablation working pressure boost solenoid valve (L4-2) in the cryoablation working pressure boost pipeline (L4) closes.

[0107] The working pressure of the liquid working fluid pressure vessel (C1) is dynamically maintained within the working pressure range. When the pressure collected by the liquid working fluid pressure sensor (C1-1) is higher than the first pressure reduction opening threshold, the cryoablation working pressure pressure reducing solenoid valve (L3-2) in the cryoablation working pressure pressure reducing pipeline (L3) is opened, and the gaseous working fluid in the liquid working fluid pressure vessel (C1) is discharged to the atmosphere through the cryoablation working pressure pressure reducing pipe (L3-1) for pressure reduction; when the pressure collected by the liquid working fluid pressure sensor (C1-1) is lower than the first pressure reduction closing threshold, the cryoablation working pressure pressure reducing solenoid valve (L3-2) in the cryoablation working pressure pressure reducing pipeline (L3) is closed.

[0108] When the first boost opening threshold, the first boost closing threshold, the first decompression opening threshold and the first decompression closing threshold are reached, the working pressure of the liquid working fluid pressure vessel (C1) is dynamically maintained within the working pressure range; the first boost opening threshold is less than the first boost closing threshold; the first decompression opening threshold is greater than the first decompression closing threshold; the lower limit of the working pressure range of the liquid working fluid pressure vessel (C1) is less than the first boost opening threshold; and the upper limit of the working pressure range of the liquid working fluid pressure vessel (C1) is greater than the first decompression opening threshold.

[0109] In one embodiment, the second pressure vessel is equipped with a second pressure sensor (i.e., gaseous working fluid pressure sensor C2-1) to obtain a second current pressure. The controlled elements on the fifth pipeline are a fifth solenoid valve (i.e., gaseous working fluid output solenoid valve L5-4) and a fifth pressure control element (i.e., gaseous working fluid output pressure control element L5-5), which are connected in series between the third and second pressure vessels. The fifth solenoid valve opens when the second current pressure falls below a preset second pressure value, connecting the third and second pressure vessels. The fifth pressure control element automatically controls its output pressure to be lower than its input pressure. Of course, if the second pressure vessel is overpressured, it also requires pressure reduction. In one embodiment, the second pressure vessel is equipped with an exhaust pressure relief pipeline equipped with a solenoid valve (i.e., gaseous working fluid pressure relief valve C2-2) that opens at a preset pressure to relieve pressure.

[0110] The automatic control of the second pressure vessel is:

[0111] The working pressure of the gaseous working fluid pressure vessel (C2) is dynamically maintained within a working pressure range through a gaseous working fluid output pipeline (L5), a gaseous working fluid pressure sensor (C2-1), and a gaseous working fluid pressure relief valve (C2-2); the gaseous working fluid pressure sensor (C2-1) collects a second current pressure of the gaseous working fluid pressure vessel (C2), and the second current pressure is used to determine whether the working pressure of the gaseous working fluid pressure vessel (C2) is within a desired range.

[0112] The working pressure of the gaseous working medium pressure vessel (C2) is dynamically maintained within the working pressure range. When the pressure sensed by the gaseous working medium pressure sensor (C2-1) drops to a second boost opening threshold, the gaseous working medium output solenoid valve (L5-4) in the gaseous working medium output pipeline (L5) opens, and the gaseous working medium in the phase change pressure vessel (C3) enters the gaseous working medium pressure vessel (C2) through the gaseous working medium output pipe (L5-1) and after being decompressed by the gaseous working medium output pressure control element (L5-5), thereby compensating for the boost pressure of the second pressure vessel. When the pressure sensed by the gaseous working medium pressure sensor (C2-1) exceeds a second boost closing threshold, the gaseous working medium output solenoid valve (L5-4) in the gaseous working medium output pipeline (L5) closes.

[0113] The working pressure of the gaseous working fluid pressure vessel (C2) is dynamically maintained within the working pressure range. When the pressure collected by the gaseous working fluid pressure sensor (C2-1) is higher than the second pressure reduction opening threshold, the gaseous working fluid pressure relief valve (C2-2) opens, and the gaseous working fluid pressure vessel (C2) is discharged to the atmosphere through the gaseous working fluid pressure relief valve (C2-2) to reduce pressure. When the pressure collected by the gaseous working fluid pressure sensor (C2-1) is lower than the second pressure reduction closing threshold, the gaseous working fluid pressure relief valve (C2-2) is closed.

[0114] The second boost opening threshold, the second boost closing threshold, the second decompression opening threshold and the second decompression closing threshold dynamically maintain the working pressure of the gaseous working medium pressure vessel (C2) within the working pressure range; the second boost opening threshold is less than the second boost closing threshold; the second decompression opening threshold is greater than the second decompression closing threshold; the lower limit of the working pressure range of the gaseous working medium pressure vessel (C2) is less than the second boost opening threshold; and the upper limit of the working pressure range of the gaseous working medium pressure vessel (C2) is greater than the second decompression opening threshold.

[0115] In one embodiment, a third pressure sensor (i.e., a phase change pressure transmitter L5-2) for monitoring the third pressure vessel is provided on the fifth pipeline (i.e., the gaseous working medium output pipeline L5) to obtain a third current pressure. A heating device (i.e., a phase change heating device C3-2) is provided on the third pressure vessel to heat the liquid working medium in the third pressure vessel to change its phase into a gaseous working medium and increase the third current pressure. When the third current pressure reaches a third preset pressure value, the heating device stops heating.

[0116] In this embodiment, the third pressure vessel is equipped with a liquid level sensor (C3-4) and a temperature sensor (C3-5) to obtain a third current liquid level and a third current temperature. The third current liquid level and the third current temperature are used to determine the control of the heating device. When the third current liquid level and the third current temperature meet the expected conditions, the heating device stops heating.

[0117] See Figure 6 One end of a gaseous working medium output pipe (L5) fixed to the top end cap of the liquid working medium pressure vessel (C1) extends into the phase change pressure vessel (C3). The bottom of the phase change pressure vessel (C3) is provided with a liquid working medium one-way flow device (C3-1), which can be understood as being located below the liquid level in the first pressure vessel. The liquid working medium in the liquid working medium pressure vessel (C1) can enter the phase change pressure vessel (C3) through the liquid working medium one-way flow device (C3-1). The liquid working medium one-way flow device (C3-1) prevents liquid or gaseous working medium from entering the liquid working medium pressure vessel (C1) from the phase change pressure vessel (C3). The phase change heating device (C3-2) is located in the phase change pressure vessel (C3). In order to avoid affecting the liquid working medium in the first vessel during the heating process, an isolation layer for isolating heat conduction (i.e., a vessel insulation layer (C3-3)) is provided on the third pressure vessel. The vessel insulation layer (C3-3) thermally isolates the phase change pressure vessel (C3) from the liquid working medium pressure vessel (C1).

[0118] Automatic pressure control of the third pressure vessel (i.e. phase change pressure vessel C3):

[0119] The gaseous working medium in the phase change pressure vessel (C3) can enter the gaseous working medium pressure vessel (C2) through the gaseous working medium output pipeline (L5).

[0120] The working pressure of the phase change pressure vessel (C3) is dynamically maintained within the working pressure range through the gaseous working medium output pipeline (L5), the liquid working medium one-way circulation device (C3-1), the phase change heating device (C3-2), the phase change pressure transmitter (L5-2), the liquid level sensor (C3-4) and the temperature sensor (C3-5); the phase change pressure transmitter (L5-2) collects the third current pressure of the phase change pressure vessel (C3), and the third current pressure is used to determine whether the working pressure of the phase change pressure vessel (C3) is within the expected range.

[0121] The working pressure of the phase change pressure vessel (C3) is dynamically maintained within the working pressure range. During the period when the pressure collected by the phase change pressure transmitter (L5-2) increases from the third boost opening threshold to the third boost closing threshold, the liquid level information of the liquid level sensor (C3-4) and the temperature information of the temperature sensor (C3-5) are used to determine whether the boosting process is effective:

[0122] During the period when the pressure collected by the phase change pressure transmitter (L5-2) is boosted from the third boost on threshold to the third boost off threshold, when the liquid level collected by the liquid level sensor (C3-4) is less than the first low liquid level threshold and the temperature collected by the temperature sensor (C3-5) is less than the first high temperature threshold, the pressure collected by the phase change pressure transmitter (L5-2) is greater than the third boost lower limit threshold, the boosting process ends, the phase change heating device (C3-2) stops heating, and the boosting process is valid; when the liquid level collected by the liquid level sensor (C3-4) is less than the first low liquid level threshold and the temperature collected by the temperature sensor (C3-5) is greater than the first high temperature threshold, the pressure collected by the phase change pressure transmitter (L5-2) is less than the third boost lower limit threshold, the boosting process ends, the phase change heating device (C3-2) stops heating, the boosting process is invalid, and the boosting process as described above is repeated.

[0123] Of course, during the entire pressure linkage process, the phase change pressure vessel (C3) is over-pressurized. Therefore, the third pressure vessel is provided with an exhaust pressure relief pipe, on which is provided an electromagnetic valve (i.e., the phase change vessel pressure relief electromagnetic valve (L5-3)) that opens at a preset pressure to implement pressure relief, so that the third current pressure is dynamically maintained within the working pressure range. In this embodiment, the phase change vessel pressure relief electromagnetic valve (L5-3) is provided on the gaseous working medium output pipe (L5-1). When the phase change pressure transmitter (L5-2 ) drops to the third pressure reduction opening threshold, the phase change container pressure relief solenoid valve (L5-3) in the gaseous working medium output pipeline (L5) opens, and the gaseous working medium in the phase change pressure vessel (C3) is discharged to the atmosphere through the gaseous working medium output pipe (L5-1) and the phase change container pressure relief solenoid valve (L5-3), thereby reducing the pressure. When the pressure collected by the phase change pressure transmitter (L5-2) drops to the third pressure reduction closing threshold, the phase change container pressure relief solenoid valve (L5-3) in the gaseous working medium output pipeline (L5) closes.

[0124] The third boost opening threshold, the first liquid level closing threshold, the third boost closing threshold, the first low liquid level threshold, the first high temperature threshold, the third boost lower limit threshold, the third pressure reduction opening threshold and the third pressure reduction closing threshold dynamically maintain the working pressure of the phase change pressure vessel (C3) within the working pressure range; the third boost opening threshold < the third boost lower limit threshold < the third boost closing threshold; the third pressure reduction opening threshold > the third pressure reduction closing threshold; the lower limit of the working pressure range of the phase change pressure vessel (C3) < the third boost opening threshold; the upper limit of the working pressure range of the phase change pressure vessel (C3) > the third pressure reduction opening threshold; the first liquid level closing threshold > the first low liquid level threshold; the first high temperature threshold ≤ room temperature; the first low liquid level threshold, the first high temperature threshold and the third boost lower limit threshold participate in the judgment of the pressurization effectiveness of the phase change pressure vessel (C3).

[0125] The working pressure of the liquid working medium pressure vessel (C1), the working pressure of the gaseous working medium pressure vessel (C2), the working pressure of the phase change pressure vessel (C3), the first boost opening threshold, the first boost closing threshold, the first decompression opening threshold, the first decompression closing threshold, the second boost opening threshold, the second boost closing threshold, the second decompression opening threshold, the second decompression closing threshold, the third boost opening threshold, the first liquid level closing threshold, the third boost closing threshold, the first low liquid level threshold, the first high temperature threshold, the third boost lower limit threshold, the third decompression opening threshold and the third decompression closing threshold are dynamically maintained within their respective working pressure ranges.

[0126] The working pressure of the pressure vessel is dynamically maintained within the working pressure range. The cryoablation working pressure boost solenoid valve (L4-2), the gaseous working fluid output solenoid valve (L5-4), and the phase change container pressure relief solenoid valve (L5-3) participate in the pressure boosting process of the pressure vessel; the cryoablation working pressure reducing solenoid valve (L3-2), the gaseous working fluid pressure relief valve (C2-2), and the phase change container pressure relief solenoid valve (L5-3) participate in the pressure relief process of the pressure vessel; it is prohibited for the cryoablation working pressure boost solenoid valve (L4-2) and the cryoablation working pressure reducing solenoid valve (L3-2) to operate at the same time; it is prohibited for the gaseous working fluid output solenoid valve (L5-4) and the gaseous working fluid pressure relief valve (C2-2) to operate at the same time.

[0127] The working pressure range of each pressure vessel is dynamic. The specific range setting method is:

[0128] See Figure 1 The cryoablation equipment and the second pressure vessel are connected through the seventh pipeline (i.e., the return air recovery pipeline L7) and the eighth pipeline (i.e., the system flow monitoring and recovery condition control pipeline L8). The eighth pipeline is equipped with a system flow monitoring and recovery condition control flowmeter (L8-4), and the setting of the working pressure range can be adjusted according to the flow data of the system flow monitoring and recovery condition control flowmeter (L8-4) in the system flow monitoring and recovery condition control pipeline (L8).

[0129] The pressure compensation for C1 in the above embodiment can be performed at any stage.

[0130] In cryoablation systems using nitrogen or liquid nitrogen as the refrigerant, it is necessary to heat liquid nitrogen to generate nitrogen gas for freezing or rewarming. However, liquid nitrogen is highly susceptible to vaporization and, upon heating, rapidly generates a large amount of nitrogen gas, causing the pressure within the container to rise rapidly, posing a significant safety risk. In the above-described embodiment, a one-way flow device responsive to pressure control is used to controllably flow the liquid nitrogen within the liquid nitrogen container into a heating device with an insulating structure, thereby controlling the amount of liquid nitrogen vaporized and improving safety during vaporization.

[0131] Combine Figure 7A 、 Figure 7B The aforementioned structure of the phase change pressure vessel C3 is further described. The phase change pressure vessel (C3) is provided with a liquid working medium unidirectional flow device at the bottom, a gas working medium output solenoid valve is connected to the top, and a phase change heating device is provided inside. The liquid working medium unidirectional flow device has an internal space, a bottom port connected to the internal space, a top port connected to the interior of the phase change pressure vessel (C3), a side wall port connecting the internal space and the interior of the phase change pressure vessel (C3), and a unidirectional flow device sealing ball (C3-1-4) slidably installed in the internal space.

[0132] The sealing plate (C3-1-2) that is movably sealed in the internal space has one side facing the top port and the other side linked to the sealing ball of the one-way flow device. Under the action of the internal pressure of the phase change pressure vessel (C3), the sealing ball of the one-way flow device is driven to seal the bottom port. The sealing plate avoids the side wall port during its own movement. The sealing plate adapts to the internal space and can allow the liquid working medium to flow in from the bottom port and then out from the side wall port, thereby preventing the liquid working medium from flowing out of the top port. The sealing plate is subjected to the pressure from the phase change pressure vessel C3 on the side facing the top port (the pressure generated by the liquid and / or gaseous working medium), and indirectly transmits this pressure to the sealing ball. The sealing ball is also subjected to the pressure from the first pressure vessel at the bottom port. The interaction of the two pressures causes the sealing ball to move, and the corresponding bottom port is opened or sealed.

[0133] The phase-change heating device heats the liquid working fluid within the phase-change pressure vessel C3, vaporizing it to increase the pressure within the phase-change pressure vessel and prepare for subsequent pressure buildup within the second pressure vessel C2. For example, once the pressure within the third pressure vessel meets a preset condition, the gaseous working fluid output solenoid valve opens and delivers the gaseous working fluid to the second pressure vessel.

[0134] The top of the phase-change pressure vessel (C3) is connected to a phase-change pressure relief solenoid valve (L5-3). The phase-change pressure vessel (C3) is also equipped with a liquid level sensor (C3-4), a temperature sensor (C3-5), a phase-change pressure transmitter (L5-2), and a vessel insulation layer (C3-3). A stopper (C3-1-1) is fixed within the internal space. When the one-way flow device's sealing ball moves away from the bottom opening to its limit position under external pressure at the bottom opening, the stopper is positioned on the side of the sealing plate facing the top opening and abuts against the sealing plate.

[0135] The present application also provides a control method for a phase change pressure system, comprising:

[0136] The liquid working medium one-way flow device is turned on;

[0137] The liquid working medium in the liquid working medium pressure vessel (C1) enters the phase change pressure vessel (C3) through the liquid working medium one-way flow device (C3-1);

[0138] The liquid working medium in the phase change pressure vessel (C3) is heated and gasified by using a phase change heating device.

[0139] The condition for opening the liquid working medium one-way flow device is that the pressure of the liquid working medium pressure vessel (C1) is low.

[0140] The condition for the liquid working medium to flow into the phase change pressure vessel is that the pressure or liquid level of the liquid working medium pressure vessel (C1) meets the expected

[0141] The condition for the liquid working fluid to be vaporized by heat is that the pressure of the liquid working fluid pressure vessel (C1) meets the expectation.

[0142] like Figure 7A In the initial state, when the pressure in the phase change pressure vessel (C3) is close to atmospheric pressure (which can be achieved through the phase change vessel pressure relief solenoid valve (L5-3)), the pressure in the liquid working fluid pressure vessel (C1) is greater than the pressure in the phase change pressure vessel (C3) in the current state. Under the action of the static pressure (C3-1-5) in the liquid working fluid pressure vessel (C1), the one-way flow device sealing ball (C3-1-4) is pushed upward to compress the spring (C3-1-3). Under the action of the stopper (C3-1-1), the sealing plate (C3-1-2) connected to the spring (C3-1-3) cannot continue to move upward. At this time, the liquid working fluid in the liquid working fluid pressure vessel (C1) enters the phase change pressure vessel (C3) through the flow path (C3-1-6) from the side wall opening of the one-way flow device (C3-1) containing liquid working fluid. The sealing plate (C3-1-2) and the side wall of the liquid working medium one-way circulation device (C3-1) form a dynamic sealing structure; therefore, under the above structure, the fluid path (C3-1-6) is unique.

[0143] like Figure 7B When the liquid working medium in the liquid working medium pressure vessel (C1) enters the phase change pressure vessel (C3), the phase change heating device (C3-2) continuously heats the liquid working medium entering the phase change pressure vessel (C3), further increasing the pressure of the phase change pressure vessel (C3). Under the action of the static pressure (C3-1-5) within the phase change pressure vessel (C3), the sealing plate (C3-1-2) connected to the spring (C3-1-3) is pushed downward, compressing the spring (C3-1-3). This further causes the one-way flow device sealing ball (C3-1-4) to seal the liquid working medium one-way flow device (C3-1), preventing the flow path (C3-1-6) from passing through the sealed area of the liquid working medium one-way flow device (C3-1).

[0144] participate Figure 8 In another embodiment, the liquid working medium one-way circulation device (C3-1) is a cryogenic fluid micro pump.

[0145] The corresponding control method is as follows: after the phase change pressure vessel (C3) is released through the phase change vessel pressure relief solenoid valve (L5-3), the cryogenic fluid micro-pump is turned on to pump the liquid working medium in the liquid working medium pressure vessel (C1) to the phase change pressure vessel (C3). Then, when the liquid level information collected by the liquid level sensor (C3-4) reaches a threshold, the cryogenic fluid micro-pump is turned off. The liquid working medium entering the phase change pressure vessel (C3) is further heated by the phase change heating device (C3-2), thereby further pressurizing the phase change pressure vessel (C3).

[0146] When the system is running, the working pressure of the phase change pressure vessel (C3) is dynamically maintained within the working pressure range. When the pressure collected by the phase change pressure transmitter (L5-2) drops to the third boost opening threshold, the phase change vessel pressure relief solenoid valve (L5-3) in the gaseous working medium output pipe (L5) opens, and the gaseous working medium in the phase change pressure vessel (C3) is discharged to the atmosphere through the gaseous working medium output pipe (L5-1) and the phase change vessel pressure relief solenoid valve (L5-3), so that the pressure collected by the phase change pressure transmitter (L5-2) is further reduced to the opening threshold of the liquid working medium one-way circulation device, and the liquid working medium in the liquid working medium pressure vessel (C1) enters the phase change pressure vessel (C3) through the liquid working medium one-way circulation device (C3-1); the liquid level sensor (C3-4) collects the liquid level data of the liquid working medium entering the phase change pressure vessel (C3). When the liquid level reaches the first liquid level closing threshold, the gaseous working medium is discharged to the atmosphere through the gaseous working medium output pipe (L5-1) and the phase change vessel pressure relief solenoid valve (L5-3), so that the pressure collected by the phase change pressure transmitter (L5-2) is further reduced to the opening threshold of the liquid working medium one-way circulation device. The phase change container pressure relief solenoid valve (L5-3) in the medium output pipeline (L5) is closed, and the phase change heating device (C3-2) is started to heat and vaporize the liquid working medium into a gaseous working medium, thereby increasing the pressure in the phase change pressure vessel (C3). As the pressure increases, the liquid working medium one-way flow device (C3-1) is closed; the phase change heating device (C3-2) continues to heat the liquid working medium entering the phase change pressure vessel (C3), further pressurizing the phase change pressure vessel (C3); when the pressure collected by the phase change pressure transmitter (L5-2) exceeds the third pressure increase shutdown threshold, the phase change heating device (C3-2) stops heating.

[0147] See attached Figure 1 An embodiment of the present application discloses a low-pressure fluid system for enhancing the performance of interventional cryoablation, comprising at least one of the following: a liquid working fluid pressure vessel (C1), a gaseous working fluid pressure vessel (C2), a phase change pressure vessel (C3), a liquid refrigerant output pipeline (L1), a pre-cooling fluid recovery pipeline (L2), a cryoablation working pressure reducing pipeline (L3), a cryoablation working pressure boosting pipeline (L4), a gaseous working fluid output pipeline (L5), a replacement and rewarming pipeline (L6), a return gas recovery pipeline (L7), a system flow monitoring and recovery condition control pipeline (L8), a vacuum degree creation pipeline (L9), and a cryoablation device (CP) serving as a cryoablation device.

[0148] The modules, containers, pipelines, and related equipment and methods described above are applicable to low-pressure cryoablation, for example, less than 3 MPa (e.g., operating pressure of approximately 0.5 MPa). Each module can independently perform certain unit operations and, in some cases, can be integrated into a more complete low-pressure fluid system. The following describes each component separately, but does not strictly require them to be configured simultaneously:

[0149] 1) Pressure vessels containing liquid and gaseous working fluids: liquid working fluid pressure vessel (first pressure vessel C1), gaseous working fluid pressure vessel (second pressure vessel C2), and phase change pressure vessel (third pressure vessel C3).

[0150] ① A first pressure vessel (C1) stores a liquid working medium therein and is connected to the cryoablation device CP via a first pipeline L1 to transport the liquid working medium;

[0151] The first pressure vessel C1 is connected to the second pressure vessel C2 through a fourth pipeline L4; a third pressure vessel C3 is provided in the first pressure vessel C1, which can change the liquid working medium into a gaseous working medium.

[0152] The first pressure vessel C1 is provided with a third pipeline L3 for exhaust and pressure relief;

[0153] The liquid working fluid pressure vessel (C1), preferably a Dewar pressure vessel, is used to store the liquid working fluid during the freezing process in a cryoablation procedure; and comprises: a liquid working fluid pressure sensor (C1-1) and a liquid working fluid level sensor (C1-2).

[0154] ② A gaseous working medium pressure vessel (i.e., a second pressure vessel C2), wherein the second pressure vessel (C2) stores a gaseous working medium therein and is connected to the first pressure vessel (C1) via a fourth pipeline L4 and delivers the gaseous working medium to the first pressure vessel (C1);

[0155] The second pressure vessel (C2) is connected to the third pressure vessel (C3) via a fifth pipeline (L5) and receives the gaseous working medium from the third pressure vessel (C3);

[0156] The second pressure vessel (C2) is connected to the cryoablation device (CP) via a sixth pipeline (L6) and transports the heated gaseous working medium;

[0157] The second pressure container (C2) is connected to the cryoablation device (CP) and / or the gaseous working medium of the first pipeline (L1) through an eighth pipeline (L8).

[0158] The preferred embodiment is a Dewar pressure vessel, which is used to store gaseous working fluids used in pre-displacement, rewarming process and return gas channel recovery during cryoablation procedures; and comprises: a gaseous working fluid pressure sensor (C2-1) and a gaseous working fluid pressure relief valve (C2-2).

[0159] ③The phase change pressure vessel (i.e., the third pressure vessel C3) is connected to and transported to the second pressure vessel (C2) through the fifth pipeline (L5).

[0160] It is used to change the phase of liquid working fluid into gaseous working fluid, and then transport the phase-changed gas through the gaseous working fluid output pipeline (L5) and the pressure control element (L5-5) to the gaseous working fluid pressure vessel (C2). It includes: a liquid working fluid one-way flow device (C3-1), a phase change heating device (C3-2), a vessel insulation layer (C3-3), a liquid level sensor (C3-4), and a temperature sensor (C3-5).

[0161] 2) Nine functional pipelines including valves, sensors and control elements: liquid refrigerant output pipeline (first pipeline L1), pre-cooling fluid recovery pipeline (second pipeline L2), cryoablation working pressure reduction pipeline (third pipeline L3), cryoablation working pressure boosting pipeline (fourth pipeline L4), gaseous working fluid output pipeline (fifth pipeline L5), replacement and rewarming pipeline (sixth pipeline L6), return air recovery pipeline (seventh pipeline L7), system flow monitoring and recovery condition control pipeline (eighth pipeline L8), and vacuum creation pipeline (ninth pipeline L9).

[0162] ① A conveying device comprising the above embodiment, wherein the liquid refrigerant output pipeline (first pipeline L1) is used to transmit the liquid working medium, comprising:

[0163] Liquid refrigerant pipe (L1-1); liquid refrigerant output valve (L1-2); safety pressure relief valve (L1-3); and liquid refrigerant output pipeline pressure transmitter (L1-4) and temperature sensor (L1-5) involved in closed-loop control, used to monitor the state parameters of the fluid entering the flexible cryoprobe; liquid refrigerant output one-way valve (L1-6) to prevent backflow.

[0164] ② A gaseous working medium flows through the interior of the pre-cooling fluid recovery pipeline (i.e., the second pipeline (L2), one end of the second pipeline (L2) is connected to the first pipeline (L1), and the other end is connected to the eighth pipeline (L8) and is finally transported to the second pressure vessel (C2).

[0165] The second pipeline (L2) is used to transmit the fluid working medium to the system flow monitoring and recovery condition control pipeline (L8) during the pre-cooling process in the cryoablation procedure, and includes:

[0166] Pre-cooling fluid recovery tube (L2-1); pre-cooling fluid recovery solenoid valve (L2-2), which opens the heat exchanger during the cryoablation procedure and closes after reaching the pre-cooling temperature threshold range; pre-cooling fluid recovery one-way valve (L2-3) to prevent backflow.

[0167] ③ A cryoablation working pressure reducing pipeline (i.e., the third pipeline (L3), which is connected to the first pressure vessel (C1) and is used to release the pressure of the liquid working medium Dewar pressure vessel (C1). It includes:

[0168] A cryoablation working pressure reducing pipe (L3-1); a cryoablation working pressure reducing solenoid valve (L3-2), which opens when the pressure of the liquid working medium in the liquid nitrogen working medium pressure container (C1) exceeds the release pressure threshold, and closes when the pressure falls below the release pressure threshold.

[0169] ④ A cryoablation working pressure boosting pipeline (i.e., the fourth pipeline (L4), which connects the first pressure vessel (C1) and the second pressure vessel (C2), and is used to input the gaseous working medium in the gaseous working medium pressure vessel (C2) into the liquid working medium Dewar pressure vessel (C1) for pressurization, including:

[0170] A cryoablation operating pressure booster tube (L4-1); a cryoablation operating pressure booster solenoid valve (L4-2) opens when the liquid working fluid pressure in the liquid nitrogen working fluid pressure vessel (C1) falls below the boost pressure threshold, and closes when it rises above the boost pressure threshold. A cryoablation operating pressure control element (L4-3) participates in closed-loop control and is used to adjust the cryoablation operating pressure.

[0171] ⑤ The gaseous working medium output pipeline (i.e., the fifth pipeline (L5) connects the third pressure vessel (C3) and the second pressure vessel (C2) and is used to input the gaseous working medium in the phase change pressure vessel (C3) into the gaseous working medium pressure vessel (C2) for pressurization, including:

[0172] A gaseous working medium output pipe (L5-1), a pressure monitoring element of the phase change pressure vessel (C3): a phase change pressure transmitter (L5-2); a phase change vessel pressure relief solenoid valve (L5-3), which is opened to empty the gaseous working medium in the phase change pressure vessel (C3), or to create a pressure difference between the liquid working medium pressure vessel (C1) and the phase change pressure vessel (C3), so that the liquid working medium enters the phase change pressure vessel (C3) from the liquid working medium pressure vessel (C1), and is closed when liquid working medium enters; when the pressure threshold of the phase change pressure transmitter (L5-2) is higher than the gaseous working medium output pressure threshold, the gaseous working medium output solenoid valve (L5-4) is opened, otherwise it is closed; a gaseous working medium output pressure control element (L5-5) is used to adjust the pressure in the gaseous working medium pressure vessel (C2).

[0173] ⑥ The displacement and rewarming pipeline (i.e., the sixth pipeline L6) connects the second pressure vessel (C2) and the cryoablation device (CP) and is used to selectively heat the gaseous working medium in the gaseous working medium pressure vessel (C2) during the displacement process in the cryoablation procedure and then transport it to the cryoablation device (CP), including:

[0174] Replacement and rewarming tube (L6-1); replacement and rewarming solenoid valve (L6-2), which opens when in the replacement process of the cryoablation procedure and closes after the replacement process, and is used to replace the air in the cryoablation equipment; opens when in the rewarming process of the cryoablation procedure, and at the same time the replacement and rewarming heat exchanger (L6-3) is started, and is used to heat the gas working medium in the replacement and rewarming tube (L6-1) to reach the threshold temperature, and at the same time the rewarming temperature sensor (L6-4) participates in the rewarming process, and cooperates to adjust the heating power of the replacement and rewarming heat exchanger (L6-2) so that the gas working medium in the replacement and rewarming tube (L6-1) reaches the threshold temperature; replacement and rewarming one-way valve (L6-5) is used to prevent backflow.

[0175] ⑦ The return gas recovery pipeline (i.e., the seventh pipeline (L7) has one end connected to the cryoablation device (CP) and the other end connected to the eighth pipeline (L8), which is used to transport the return gas generated during the freezing process during the cryoablation procedure to the system flow monitoring and recovery condition control pipeline (L8), including:

[0176] Return air recovery pipe (L7-1); return air recovery pipe one-way valve (L7-2) to prevent backflow.

[0177] ⑧ The system flow monitoring and recovery condition control pipeline (i.e., one end of the eighth pipeline (L8) is connected to the seventh pipeline (L7) and the second pipeline (L2) at the same time, and the other end is connected to the second pressure vessel (C2), which is used to heat the fluid working medium flowing from the pre-cooling fluid recovery pipeline (L2) during the pre-cooling process in the cryoablation procedure and then pump it to the gaseous working medium pressure vessel (C2). In addition, during the freezing process in the cryoablation procedure, the fluid working medium flowing from the return gas recovery pipeline (L7) is heated and then pumped to the gaseous working medium pressure vessel (C2) after the flow rate is measured by a flow meter; the measured flow rate participates in the pressure control of the system. Including:

[0178] System flow monitoring and recovery condition control pipe (L8-1); System flow monitoring and recovery condition control heat exchanger (L8-2), used to heat the fluid flowing in from the pre-cooling fluid recovery pipe (L2) during the pre-cooling process in the cryoablation procedure and make it reach the threshold temperature; and the fluid flowing in from the return air recovery pipe (L7) during the freezing process in the cryoablation procedure and make it reach the threshold temperature; System flow monitoring and recovery condition control temperature sensor (L8-3) participates in closed-loop control and is used to cooperate with the adjustment of the heating power of the system flow monitoring and recovery condition control heat exchanger (L8-2), The fluid in the system flow monitoring and recovery condition control pipe (L8-1) reaches the threshold temperature. If the fluid cannot reach the threshold temperature after heating, the gas recovery release valve (L8-7) opens, releasing the fluid to the atmosphere. The system flow monitoring and recovery condition control flowmeter (L8-4) is primarily used to monitor the freezing process during the cryoablation procedure. The fluid flow entering the system flow monitoring and recovery condition control pipe (L8-1) from the return gas recovery pipe (L7-1) participates in closed-loop control, predicting the cryoablation effect and coordinating pressure regulation to ensure the desired cryoablation effect. The system flow monitoring and recovery condition control extraction booster pump (L8-5) adjusts the suction power and operating pressure to further promote smooth gas return and achieve the desired cryoablation effect. The system flow monitoring and recovery condition control check valve (L8-6) prevents backflow.

[0179] ⑨The vacuum creation pipeline (i.e., the ninth pipeline L9) connects the cryoablation device (CP) and the vacuum device (L9-3) to create a high vacuum for the cryoablation device (CP) to achieve a good vacuum insulation effect, including:

[0180] Vacuum creation tube (L9-1); vacuum gauge (L9-2) is used to monitor whether the vacuum degree reaches the threshold requirement; vacuum creation pump group is used to create high vacuum degree, and the flexible freezing probe has good vacuum insulation effect.

[0181] 3) Cryoablation device (CP) containing temperature sensor and heating element.

[0182] ① The cryoablation device (CP) can be a flexible cryoprobe, etc., which is used to enter the human body through a natural cavity and perform a cryoablation procedure on the lesion, including:

[0183] A structure used to enhance the performance of interventional cryoablation; the distal thermocouple (CP1) of the cryoablation device is used to monitor the temperature inside the cryoprobe and participate in closed-loop control; the distal nickel-chromium wire of the cryoablation device is used for the rewarming process during the cryoablation procedure.

[0184] The following combination Figures 10 to 15 Explain the workflow of the cryoablation system

[0185] The various steps in the figure are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the figure may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0186] 1) The system starts, initializes, and reads the control threshold parameters stored in the memory; at the same time, it obtains the data of the system sensors.

[0187] 2) First, determine the liquid level in the liquid working medium Dewar pressure vessel (C1). LLC1-2_ Lower Limit is the low liquid level warning threshold of the vessel. Execute the judgment procedure:

[0188] If the current liquid level of the liquid working fluid level sensor (C1-2) is less than LLC1-2_Lower Limit, the system determines that the liquid level cannot sustain the current cryoablation procedure. In other words, LLC1-2_Lower Limit represents the liquid nitrogen volume required for one cryoablation procedure, including redundancy. The liquid nitrogen replenishment procedure is then executed. When LLC1-2_CL exceeds LLC1-2_Upper Limit, liquid nitrogen refilling is complete.

[0189] If the current liquid level LLC1-2_CL of the liquid working fluid level sensor (C1-2) is ≥ LLC1-2_ Lower Limit, the system considers that the cryoablation procedure can be performed.

[0190] 3) Determine the pressure inside the liquid working medium Dewar pressure vessel (C1), PC1_IWP is the pressure threshold at the time of initialization of the pressure vessel; execute the judgment procedure:

[0191] If the current pressure of the liquid working fluid pressure sensor (C1-1) is PC1-1_CP ≤ PC1_IWP, the system assumes that the pressure within the pressure vessel meets the initialization pressure requirement and can continue with subsequent procedures. PC1_IWP is the initialization pressure of the liquid working fluid Dewar pressure vessel (C1) before use in a cryoablation procedure. This pressure is typically the pressure of the liquid working fluid Dewar pressure vessel (C1) when it is not in use. Note: The initialization pressure of the pressure vessel, PC1_IWP, must be less than the operating pressure of the liquid working fluid Dewar pressure vessel, PC1_WP.

[0192] If the current pressure of the liquid working fluid pressure sensor (C1-1) PC1-1_CP>PC1_IWP, the pressure relief procedure is executed, and the cryoablation working pressure relief solenoid valve (L3-2) is opened to relieve the pressure until PC1-1_CP≤PC1_IWP.

[0193] 4) Determine the pressure inside the gaseous working medium pressure vessel (C2). PC2_IWP is the pressure threshold value during initialization of the pressure vessel. Execute the determination procedure:

[0194] If the current pressure PC2-1_CP of the gaseous working fluid pressure sensor (C2-1) is ≤PC2_IWP, the system considers that the pressure in the pressure vessel meets the pressure requirements at the time of initialization and can continue to execute subsequent procedures; PC2_IWP is the initialization pressure of the gaseous working fluid pressure vessel (C2) before the cryoablation procedure is used. This pressure is usually the gaseous working fluid stored in the gaseous working fluid pressure vessel (C2) after the last cryoablation procedure; since the gas in the gaseous working fluid pressure vessel (C2) is the gas recovered during the pre-cooling process and the cryoablation process, the gas will be output during the rewarming process. In order to ensure normal recovery during the pre-cooling and cryoablation processes for the next surgery, the pressure PC2_IWP is less than the working pressure PC2_WP of the gaseous working fluid pressure vessel (C2).

[0195] If the current pressure of the gaseous working medium pressure sensor (C2-1) PC2-1_CP>PC2_IWP, the pressure relief procedure is executed, and the gaseous working medium pressure relief valve (C2-2) is opened to relieve the pressure until PC2-1_CP≤PC2_IWP.

[0196] 5) Determine the pressure inside the phase change pressure vessel (C3). PC3_IWP is the pressure threshold at the time of initialization of the pressure vessel. Execute the determination procedure:

[0197] If the current pressure PL5-2_CP of the phase change pressure transmitter (L5-2) is less than or equal to PC3_IWP, the system will determine that the pressure inside the pressure vessel meets the initialization pressure requirement and can continue to execute subsequent procedures. This pressure PC3_IWP is less than the working pressure PC3_WP inside the phase change pressure vessel (C3).

[0198] If the current pressure PL5-2_CP of the phase change pressure transmitter (L5-2) is greater than PC3_IWP, the pressure relief procedure is executed and the phase change container pressure relief solenoid valve (L5-3) is opened to relieve the pressure until PL5-2_CP ≤ PC3_IWP.

[0199] 6) Determine whether the current pressure PL5-2_CP of the phase-change pressure transmitter (L5-2) is greater than the current pressure PC2-1_CP of the gaseous working fluid pressure sensor (C2-1). The gaseous working fluid output solenoid valve (L5-4) is opened, and the output pressure of the gaseous working fluid output pressure control element (L5-5) is set to PL5-5_SP_OUT > PC2-1_CP. At this point, the gaseous working fluid in the phase-change pressure vessel (C3) enters the gaseous working fluid pressure vessel (C2). This continues until PL5-2_CP - PC2-1_CP < ΔP0, meaning the current pressure in the phase-change pressure vessel (C3) equals the pressure in the gaseous working fluid pressure vessel (C2). The gaseous working fluid output solenoid valve (L5-4) is closed, and the output of the gaseous working fluid output pressure control element (L5-5) is shut off. This utilizes the gaseous working fluid in the phase-change pressure vessel (C3), improving its efficiency.

[0200] 7-1) Open the liquid refrigerant outlet valve (L1-2), starting the cryoablation precooling process. All components in the precooling fluid recovery pipeline (L2) and the system flow monitoring and recovery condition control pipeline (L8) enter operation. Open the precooling fluid recovery solenoid valve (L2-2), and the system flow monitoring and recovery condition control heat exchanger (L8-2) will start.

[0201] The system flow monitoring and recovery condition control flowmeter (L8-4) and the system flow monitoring and recovery condition control extraction booster pump (L8-5) have fluid temperature restrictions. Therefore, the system sets temperature thresholds: TL8-2_ET_ Lower Limit: The first heat exchange temperature of the system flow monitoring and recovery condition control heat exchanger; and TL8-2_ET_ Upper Limit: The second heat exchange temperature of the system flow monitoring and recovery condition control heat exchanger; these thresholds correspond to the lower and upper limits of the temperature range, respectively.

[0202] If: The current fluid temperature collected by the system flow monitoring and recovery condition control temperature sensor (L8-3):

[0203] TL8-3_CT≥TL8-2_ET_ Lower Limit&&TL8-3_CT≤TL8-2_ET_ Upper Limit; the gas working medium recovery release valve (L8-7) is closed, and the fluid passes through the system flow monitoring and recovery condition control flowmeter (L8-4) and the system flow monitoring and recovery condition control extraction booster pump (L8-5) into the gaseous working medium pressure vessel (C2) for pressurization.

[0204] If TL8-3_CT < TL8-2_ET_ Lower Limit || TL8-3_CT > TL8-2_ET_ Upper Limit, the gas working medium recovery and release valve (L8-7) opens. The fuzzy self-tuning PID temperature control algorithm is invoked to adjust the temperature to meet the conditions TL8-3_CT ≥ TL8-2_ET_ Lower Limit && TL8-3_CT ≤ TL8-2_ET_ Upper Limit. The gas working medium recovery and release valve (L8-7) closes, and the fluid flows through the system flow monitoring and recovery condition control flowmeter (L8-4) and the system flow monitoring and recovery condition control extraction booster pump (L8-5) into the gas working medium pressure vessel (C2) for pressurization.

[0205] The cyclic pressurization of the above steps reaches the event: the current temperature TL1-5_CT - TL1-5_PT pre-cooling threshold temperature collected by the liquid refrigerant output pipe temperature sensor (L1-5) is less than △T0||(or) the current pressure of the gaseous working fluid pressure sensor (C2-1) of the second pressurization closing pressure PC2_PB_CV-PC2-1_CP of the gaseous working fluid pressure vessel (C2) is less than △P0.

[0206] If TL1-5_CT - TL1-5_PT < △T0 occurs in the above OR logic, it indicates that the pre-cooling process is completed, the liquid refrigerant output valve (L1-2) is closed, and the system delay device is started. The delay interval △t is set so that after the liquid refrigerant output valve (L1-2) is closed, the residual fluid in the liquid refrigerant output pipeline (L1) and the pre-cooling fluid recovery pipeline (L2) enters the gaseous working fluid pressure vessel (C2); then the system flow monitoring and recovery condition control extraction booster pump (L8-5) are turned off.

[0207] If TL1-5_CT - TL1-5_PT < △T0 is false in the above OR logic, then the event PC2_PB_CV - PC2-1_CP < △P0 must have occurred. The pressure in the gaseous working fluid pressure vessel (C2) has reached the boosting requirement. Therefore, the system flow monitoring and recovery condition control extraction booster pump (L8-5) are shut down. The gas working fluid recovery release valve (L8-7) is opened to discharge the fluid in the pipeline into the atmosphere until the event TL1-5_CT - TL1-5_PT < △T0 occurs, meeting the pre-cooling condition.

[0208] Then close the liquid refrigerant output valve (L1-2), start the system delay device, and delay the interval △t so that after the liquid refrigerant output valve (L1-2) is closed, the residual fluid in the liquid refrigerant output pipeline (L1) and the pre-cooling fluid recovery pipeline (L2) enters the gaseous working fluid pressure vessel (C2); then close the system flow monitoring and recovery condition control extraction booster pump (L8-5).

[0209] Next, the pressure condition of the gaseous working fluid pressure vessel (C2) is judged. When the current pressure of the gaseous working fluid pressure sensor (C2-1) is less than △P0 (the second pressure reduction opening threshold PC2_RP_OV - PC2-1_CP), the gaseous working fluid pressure relief valve (C2-2) is opened to relieve pressure. The gaseous working fluid pressure relief valve (C2-2) is closed until the current pressure of the gaseous working fluid pressure sensor (C2-1) is less than △P0 (the second pressure reduction closing threshold PC2-1_CP - PC2_RP_CV).

[0210] 7-2) Determine whether the current pressure PL5-2_CP of the phase change pressure transmitter (L5-2) is ≥ PC1-1_CP and the current pressure PC1-1_CP of the liquid working fluid pressure sensor (C1-1); open the phase change container pressure relief solenoid valve (L5-3); and when the current pressure PL5-2_CP–atm of the phase change pressure transmitter (L5-2) is < △P0 and the first liquid level closing threshold LLC3-4_CV– LLC3-4_CL of the liquid level sensor (C3-4) is < △L0; close the phase change container pressure relief solenoid valve (L5-3) and start the phase change heating device (C3-2) to heat.

[0211] If it is determined that the current pressure PL5-2_CP of the phase change pressure transmitter (L5-2) is less than PC1-1_CP and the current liquid level value LLC3-4_CL of the phase change pressure vessel (C3) liquid level sensor (C3-4) is less than the first low liquid level threshold of LLC3-4_Lower Limit liquid level sensor (C3-4), the phase change vessel pressure relief solenoid valve (L5-3) is opened. When the current pressure PL5-2_CP–atm of the phase change pressure transmitter (L5-2) is less than △P0 and the first liquid level closing threshold LLC3-4_CV–LLC3-4_CL of the liquid level sensor (C3-4) is less than △L0, the phase change vessel pressure relief solenoid valve (L5-3) is closed, and the phase change heating device (C3-2) starts heating.

[0212] 7-2-2) If it is determined that the current pressure PL5-2_CP of the phase change pressure transmitter (L5-2) is less than PC1-1_CP and the current liquid level value LLC3-4_CL of the liquid level sensor (C3-4) of the phase change pressure vessel (C3) is greater than or equal to the first low liquid level threshold of the liquid level sensor (C3-4), the phase change heating device (C3-2) starts heating.

[0213] After the phase-change heating device (C3-2) is started, if the current pressure PL5-2_CP of the phase-change pressure transmitter (L5-2) exceeds the third boost lower limit threshold (PC3_PB_Lower Limit), and the current temperature TC3-5_CT collected by the temperature sensor (C3-5) is less than TC3-5_Upper Limit, the temperature sensor (C3-5) reaches the first high temperature threshold; the phase-change heating device (C3-2) continues heating.

[0214] Until: the current temperature TC3-5_CT collected is greater than or equal to the first high temperature threshold of the temperature sensor (C3-5) or the third boost shutdown threshold PC3_PB_CV-PL5-2_CP, and the current pressure of the variable pressure transmitter (L5-2) is less than △P0; the heating device (C3-2) stops heating.

[0215] If the current pressure PL5-2_CP of the phase change pressure transmitter (L5-2) is less than or equal to the third boost lower limit threshold (PC3_PB_Lower Limit) and the current temperature TC3-5_CT collected by the temperature sensor (C3-5) is greater than or equal to the first high temperature threshold (TC3-5_Upper Limit) of the temperature sensor (C3-5), heating is stopped, the current boost is invalidated, and the boost process is restarted. Otherwise, heating continues until one of the above judgment conditions is met.

[0216] When the device meets the requirements and the current temperature TC3-5_CT collected by the temperature sensor (C3-5) ≥ TC3-5_UpperLimit the first high temperature threshold of the temperature sensor (C3-5) or the third boost closing threshold PC3_PB_ CV-PL5-2_CP the current pressure of the pressure transmitter (L5-2) < △P0, the output program is executed. The gaseous working medium output solenoid valve (L5-4) opens, and the output pressure of the gaseous working medium output pressure control element (L5-5) is set to: PL5-5_SP_OUT>PC2-1_CP; at this time, the gaseous working medium in the phase change pressure vessel (C3) enters the gaseous working medium pressure vessel (C2); until the third boost opening threshold value of the variable pressure transmitter (L5-2) PL5-2_CP-PC3_PB_OV is less than △P0|| (or) the current pressure of the variable pressure transmitter (L5-2) PL5-2_CP - PC2-1_CP The current pressure of the gaseous working medium pressure sensor (C2-1) is less than △P0<. This limit is determined by the controller. When the gaseous working medium pressure vessel (C2) is gradually pressurized, PC2-1_CP will gradually increase. However, the pressure controller requires that the upstream pressure should be greater than the downstream pressure, so this logic should be provided here>|| (or) the second boost closing pressure of the gaseous working medium pressure vessel (C2) PC2_ When the current pressure of the PB_ CV - PC2-1_ CP gaseous working fluid pressure sensor (C2-1) is less than △P0, the gaseous working fluid output solenoid valve (L5-4) is closed and the gaseous working fluid output pressure control element (L5-5) is turned off.

[0217] The above-mentioned pressurization process may be multiple cycles until the event: the second pressurization closing pressure PC2_PB_CV of the gaseous working medium pressure container (C2) - PC2-1_CP current pressure of the gaseous working medium pressure sensor (C2-1) is less than △P0 occurs, indicating that the initialization pressurization process of the gaseous working medium pressure container (C2) is completed.

[0218] To prevent the pressure in phase-change pressure vessel C3 from being too high when stopped, a pressure relief check is introduced: if the current pressure of the phase-change pressure transmitter (L5-2) (PL5-2_CP - PC3_RP_OV) and the third pressure reduction opening threshold of the phase-change pressure vessel (C3) are less than △P0, the phase-change vessel pressure relief solenoid valve (L5-3) is opened. If the current pressure of the phase-change pressure transmitter (L5-2) (PL5-2_CP - PC3_RP_CV) and the third pressure reduction closing threshold of the phase-change pressure vessel (C3) are less than △P0, the phase-change vessel pressure relief solenoid valve (L5-3) is closed. This prevents excessive pressure in C3.

[0219] Next, the pressure condition of the gaseous working fluid pressure vessel (C2) is judged. When the current pressure of the gaseous working fluid pressure sensor (C2-1) is less than △P0 (the second pressure reduction opening threshold PC2_RP_OV - PC2-1_CP), the gaseous working fluid pressure relief valve (C2-2) is opened to relieve pressure. The gaseous working fluid pressure relief valve (C2-2) is closed until the current pressure of the gaseous working fluid pressure sensor (C2-1) is less than △P0 (the second pressure reduction closing threshold PC2-1_CP - PC2_RP_CV).

[0220] 8) After the above process, the gaseous working medium pressure vessel (C2) has met its working pressure requirements: PC2_WP; the phase change pressure vessel (C3) has also met its working pressure requirements; PC3_WP; the liquid refrigerant output pipeline (L1) has been fully pre-cooled.

[0221] Therefore, it meets the requirements of the subsequent cryoablation procedure, detects or connects the system consumables, and enters the steps of building pressure of the liquid working fluid Dewar pressure vessel (C1) and replacing the gas inside the consumables after the system is connected to the consumables.

[0222] 9) Open the replacement and rewarming solenoid valve (L6-2) to initiate the replacement process. The purpose of this replacement process is to replace the air and moisture in the consumables' internal piping with the gaseous working fluid in the gaseous working fluid pressure vessel (C2) before the freezing process. The replacement and rewarming heat exchanger (L6-3) is activated, and after a fuzzy self-tuning PID temperature control algorithm, the temperature of the replacement gas is raised to room temperature, satisfying the condition TL6-4_CT – room temperature < △T0. The gas passes through the return gas recovery pipeline (L7) and enters the system flow monitoring and recovery condition control pipeline (L8). It then enters the gaseous working fluid pressure vessel (C2) using a recovery process similar to the pre-cooling process, as follows:

[0223] The system flow monitoring and recovery condition control flowmeter (L8-4) and the system flow monitoring and recovery condition control extraction booster pump (L8-5) have fluid temperature restrictions. Therefore, the system sets temperature thresholds: TL8-2_ET_ Lower Limit: The first heat exchange temperature of the system flow monitoring and recovery condition control heat exchanger; and TL8-2_ET_ Upper Limit: The second heat exchange temperature of the system flow monitoring and recovery condition control heat exchanger; these thresholds correspond to the lower and upper limits of the temperature range, respectively.

[0224] If: The current fluid temperature collected by the system flow monitoring and recovery condition control temperature sensor (L8-3):

[0225] TL8-3_CT≥TL8-2_ET_ Lower Limit&&TL8-3_CT≤TL8-2_ET_ Upper Limit; the gas working medium recovery release valve (L8-7) is closed, and the fluid passes through the system flow monitoring and recovery condition control flowmeter (L8-4) and the system flow monitoring and recovery condition control extraction booster pump (L8-5) into the gaseous working medium pressure vessel (C2) for pressurization.

[0226] If TL8-3_CT < TL8-2_ET_ Lower Limit || TL8-3_CT > TL8-2_ET_ Upper Limit, the gas working medium recovery and release valve (L8-7) opens. The fuzzy self-tuning PID temperature control algorithm is invoked to adjust the temperature to meet the conditions TL8-3_CT ≥ TL8-2_ET_ Lower Limit && TL8-3_CT ≤ TL8-2_ET_ Upper Limit. The gas working medium recovery and release valve (L8-7) closes, and the fluid flows through the system flow monitoring and recovery condition control flowmeter (L8-4) and the system flow monitoring and recovery condition control extraction booster pump (L8-5) into the gas working medium pressure vessel (C2) for pressurization.

[0227] This replacement process is output from the gaseous working medium pressure vessel (C2) and then flows back to the gaseous working medium pressure vessel (C2). This process does not cause a sharp change in pressure, so no pressure judgment is performed during this process. In addition, the entire replacement process is maintained for a time of △t1.

[0228] The replacement process is completed and Probe_ZH_Flag is sent.

[0229] 10) Raise the pressure of the liquid working fluid dewar pressure vessel (C1) to the working pressure; open the cryoablation working pressure boost solenoid valve (L4-2); set the output pressure PL4-3_SP_OUT of the cryoablation working pressure control element (L4-3) to be greater than the first boost initialization closing threshold PC1_PB_CV; thereby causing the gaseous working fluid pressure vessel (C2) to boost the pressure of the liquid working fluid dewar pressure vessel (C1) through the cryoablation working pressure boost pipeline (L4) until: the first boost initialization closing threshold PC1_PB_CV - PC1-1_CP liquid working fluid pressure sensor (C1-1)

[0230] The collected current pressure is less than △P0, indicating that the liquid working medium Dewar pressure vessel (C1) is pressurized, the cryoablation working pressure boosting solenoid valve (L4-2) is closed, and the cryoablation working pressure control element (L4-3) is turned off.

[0231] The pressure buildup before ablation of the liquid working medium Dewar pressure vessel (C1) is completed, and PC1_PreCyro_Flag is sent.

[0232] 11-1) When the event Probe_ZH_Flag == 1 & PC1_PreCyro_Flag == 1 occurs, cryoablation is ready. Wait for the event Probe_Cyro_Star == 1; set the cryoablation delay timer to △t2; open the liquid cryogen outlet valve (L1-2); and start cryoablation timer timer2. When the cryoablation delay reaches △t2, the freezing process for this cycle ends, and the number of freezing cycles during the cryoablation process is Cryo_Cycle++. Then, close the liquid cryogen outlet valve (L1-2). The freezing process for this cryoablation cycle ends.

[0233] 11-2) The rewarming process of the cryoablation cycle begins, and the displacement and rewarming heat exchanger (L6-3) is activated. The fuzzy self-tuning PID temperature control algorithm is used to set the rewarming gas temperature to the following: TL6-4_CT < TL6-3_RW_ Upper Limit && TL6-3_RW_ Lower Limit < TL6-4_CT. Then, rewarming timer 3 is started. When the rewarming duration during cryoablation reaches △t3, the number of cycles (Cryo_Cycle++) is reset. Solenoid valve L6-2 is then closed, and the displacement and rewarming heat exchanger (L6-3) is turned off.

[0234] After a freezing and thawing cycle, determine the event:

[0235] Cryo_Cycle==Cryo_Set&&ReWarm_Cycle==RW_Set

[0236] If this happens, the freezing cycle is complete. Otherwise, the cryoablation procedure will continue. Cryoablation and rewarming are performed alternately, with the number of alternations being approximately 2 to 6 times.

[0237] 11-3) In the above process, the recovery process is executed, and the gas passes through the return air recovery pipeline (L7) and then enters the system flow monitoring and recovery condition control pipeline (L8).

[0238] Then, the gas enters the gaseous working medium pressure vessel (C2) using a recovery process similar to the pre-cooling process, as follows:

[0239] The system flow monitoring and recovery condition control flow meter (L8-4) and the system flow monitoring and recovery condition control extraction booster pump (L8-5) have limits on fluid temperature, so the system sets temperature thresholds: TL8-2_ET_ Lower Limit: the first heat exchange temperature of the system flow monitoring and recovery condition control heat exchanger and TL8-2_ET_ Upper Limit: the second heat exchange temperature of the system flow monitoring and recovery condition control heat exchanger; respectively

[0240] Corresponds to the lower limit of the temperature range and the upper limit of the temperature range.

[0241] If the current fluid temperature collected by the system flow monitoring and recovery condition control temperature sensor (L8-3) is: TL8-3_CT ≥ TL8-2_ET_ Lower Limit && TL8-3_CT ≤ TL8-2_ET_ Upper Limit; the gas working fluid recovery release valve (L8-7) is closed, and the fluid enters the gas working fluid pressure vessel (C2) for pressurization through the system flow monitoring and recovery condition control flowmeter (L8-4) and the system flow monitoring and recovery condition control extraction booster pump (L8-5).

[0242] If: TL8-3_CT<TL8-2_ET_ Lower Limit || TL8-3_CT>TL8-2_ET_ Upper Limit; the gas working medium recovery release valve (L8-7) is opened.

[0243] The fuzzy self-tuning PID temperature control algorithm is invoked to ensure that the temperature satisfies TL8-3_CT ≥ TL8-2_ET_ Lower Limit && TL8-3_CT ≤ TL8-2_ET_ Upper Limit. The gas recovery release valve (L8-7) is then closed, and the fluid flows through the system flow monitoring and recovery condition control flowmeter (L8-4) and the system flow monitoring and recovery condition control extraction booster pump (L8-5) into the gaseous working fluid pressure vessel (C2) for pressurization. If the event PC2_PB_CV-PC2-1_CP<△P0 occurs, the recovered fluid no longer enters the gaseous working fluid pressure vessel (C2) and is discharged to the atmosphere via the bypass. If the event PC2_PB_CV-PC2-1_CP<△P0 occurs, the recovered fluid no longer enters the gaseous working fluid pressure vessel (C2) and is discharged to the atmosphere via the bypass.

[0244] Cryo_Cycle==Cryo_Set&&ReWarm_Cycle==RW_Set

[0245] When it occurs, it indicates that the freezing cycle is finished, otherwise it continues to execute.

[0246] When cryoablation begins, the vacuum device (L9-3) starts working and the vacuum degree is set to Vaccum; until the cryoablation procedure is completed.

[0247] The technical features of the above-described embodiments may be combined in any manner. To simplify the description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as no contradiction exists between these combinations of technical features, they should be considered to be within the scope of this specification. When technical features of different embodiments are embodied in the same drawing, it can be deemed that the drawing also discloses examples of combinations of the various embodiments involved.

[0248] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A cryoablation system, characterized in that: comprising a first pressure vessel, a second pressure vessel, a third pressure vessel and a cryoablation device; A first pipeline for supplying liquid working medium is connected between the first pressure container and the cryoablation device; A second pipeline and an eighth pipeline for reflux liquid working medium during pre-cooling are connected between the second pressure vessel and the first pipeline. The eighth pipeline is provided with a system flow monitoring and recovery condition extraction booster pump. During pre-cooling, the liquid working medium flows from the first pressure vessel through the first pipeline, the second pipeline and the eighth pipeline in sequence to the second pressure vessel. A fourth pipeline for outputting pressure to the first pressure vessel is connected between the second pressure vessel and the first pressure vessel. When the first current pressure in the first pressure vessel is lower than a preset value, the fourth pipeline is connected so that the gaseous working medium in the second pressure vessel flows into the first pressure vessel to maintain the pressure of the first pressure vessel within the preset pressure range. The third pressure vessel is unidirectionally connected to the first pressure vessel and is connected to the second pressure vessel through the fifth pipeline to provide gaseous working medium and maintain the second pressure vessel within the preset pressure range. A seventh pipeline for recovering the working fluid passing through the cryoablation device is connected between the second pressure vessel and the cryoablation device, and the seventh pipeline intersects with the second pipeline and then connects to the second pressure vessel through an eighth pipeline; The second pressure vessel is connected to the cryoablation device via a sixth pipe, and is used to output the heated gaseous working medium to the cryoablation device during rewarming; The third pressure vessel is provided with a heating device for heating the liquid working medium in the third pressure vessel to change the phase into gaseous working medium and to maintain its own pressure within a preset pressure range.

2. The cryoablation system according to claim 1, wherein: The first pipeline has an inner and outer double-layer structure. During pre-cooling, the liquid working medium flows from the first pressure vessel through the inner layer of the first pipeline, the outer layer of the first pipeline, the second pipeline and the eighth pipeline in sequence to the second pressure vessel.

3. The cryoablation system according to claim 1, wherein: The first pressure vessel is equipped with a first pressure sensor for obtaining a first current pressure; The controlled elements on the fourth pipeline are a fourth pressure control element and a fourth solenoid valve connected in series in sequence between the second pressure vessel and the first pressure vessel; The fourth solenoid valve opens when the first current pressure reaches a first preset pressure value, connecting the second pressure vessel and the first pressure vessel, and the fourth pressure control element automatically controls its output pressure to be lower than its input pressure; The second pressure vessel is provided with a second pressure sensor for obtaining a second current pressure; The controlled elements on the fifth pipeline are a fifth solenoid valve and a fifth pressure control element which are sequentially connected in series between the third pressure vessel and the second pressure vessel; The fifth solenoid valve opens when the second current pressure is lower than the second pressure preset value, connecting the third pressure container and the second pressure container, and the fifth pressure control element automatically controls its own output pressure to be lower than its own input pressure.

4. The cryoablation system according to claim 3, wherein: The fifth pipeline is provided with a third pressure sensor for monitoring the third pressure vessel to obtain a third current pressure; When the third current pressure reaches a third preset pressure value, the heating device stops heating.

5. The cryoablation system according to claim 3, wherein: The sixth pipeline includes: a replacement and rewarming tube, one end of which is connected to the second pressure vessel and the other end of which is connected to the cryoablation device and is capable of transporting the gaseous working medium in the second pressure vessel to the cryoablation device; A replacement and rewarming solenoid valve is provided on the replacement and rewarming pipe to control the on and off of the replacement and rewarming pipe; a replacement and rewarming heat exchanger, used for heating the gas working medium in the replacement and rewarming tube; A replacement and rewarming one-way valve is provided on the replacement and rewarming pipe to limit backflow.

6. The cryoablation system according to claim 5, characterized in that: The cryoablation device is provided with a heating component, and a rewarming temperature sensor is provided on the downstream side of the replacement and rewarming heat exchanger, and the rewarming temperature sensor controls the replacement and rewarming heat exchanger accordingly; The second pressure sensor and the rewarming temperature sensor together participate in controlling the heating component.

7. The cryoablation system according to claim 6, characterized in that: The seventh pipeline includes: a gas return pipe, one end of which is connected to the outlet of the cryoablation device and the other end of which is connected to the eighth pipe; The seventh pipeline one-way valve is arranged on the return air recovery pipe to limit backflow.

8. The cryoablation system according to claim 7, characterized in that: The eighth pipeline includes: A system flow monitoring and recovery condition control pipe, one end of which is connected to the return air recovery pipe and the other end of which is connected to the second pressure vessel; The system flow monitoring and recovery condition extraction booster pump is arranged on the system flow monitoring and recovery condition control pipe; The system flow monitoring and recovery condition one-way valve is arranged on the system flow monitoring and recovery condition control pipe to limit backflow.

9. The cryoablation system according to claim 8, characterized in that: The eighth pipeline further includes: a system flow monitoring and recovery condition control heat exchanger, located upstream of the system flow monitoring and recovery condition extraction booster pump and thermally coupled to the system flow monitoring and recovery condition control pipe; The system flow monitoring and recovery condition control temperature sensor collects the fluid temperature in the system flow monitoring and recovery condition control pipe and is used to control the system flow monitoring and recovery condition control heat exchanger accordingly.

10. The cryoablation system according to claim 9, characterized in that: A system flow monitoring and recovery condition control flow meter is configured on the upstream side of the system flow monitoring and recovery condition extraction booster pump.

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