Cryoablation device and cryoablation method for pancreatic cancer in local development stage

Abstract

The invention discloses a local development stage pancreatic cancer cryoablation device and a cryoablation method, and belongs to the technical field of cryoablation, the cryoablation device provided by the invention comprises a freezing balloon, a catheter, a medium storage tank, a medium supply pipeline, a medium recovery pipeline and a refrigeration assembly. The cryoablation method provided by the invention comprises four steps of precooling, ablation, recovery and rewarming. The cryoablation device and the cryoablation method provided by the invention are low in danger coefficient, simple to operate and convenient to use, and also have the advantages of high cold utilization efficiency, accurate temperature control and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a cryoablation device and a cryoablation method for locally advanced pancreatic cancer. Background Art

[0002] In recent years, the incidence of pancreatic cancer has shown a clear upward trend both at home and abroad, and pancreatic cancer in China accounts for about a quarter of pancreatic cancer in the world. According to statistics from the National Cancer Center of China in 2021, pancreatic cancer ranks 7th in the incidence of malignant tumors in men and 11th in women in my country, and 6th in the mortality rate related to malignant tumors. Although the 5-year survival rate of pancreatic cancer has increased from less than 5% in the last century to about 9% now, it is still far behind other solid tumors.

[0003] Most patients are in the locally advanced stage, and the surgical resection rate is only 20%, and the treatment method is not ideal.

[0004] Most patients are already in the locally advanced stage when diagnosed and have missed the chance for radical surgical treatment. Statistics show that only about 20% of pancreatic cancer patients can undergo surgical treatment. There is no ideal treatment method, and conventional chemotherapy is not satisfactory.

[0005] Cryoablation is a surgical medical technology that uses freezing to eliminate target tissues. It is mostly used to treat diseases such as tumors and atrial fibrillation. The principle is to use cryogenic equipment to make the target tissue undergo a process of cooling, freezing, and thawing, thereby causing irreversible damage or necrosis to the cells. Cryoablation equipment generally includes a cryoablation generator (host) and a cryoballoon. The cryoablation generator (host) is responsible for providing a cold medium for the cryoballoon. When in use, the cryoballoon is installed at the front end of the catheter and inserted into the human body. The cryoablation generator (host) passes the cold medium from the catheter into the cryoballoon to cool it down, thereby cryoablating the target tissue.

[0006] The cryoablation generator in the prior art generally adopts a high-pressure gas throttling refrigeration method. When the high-pressure gas flows through a small hole and adiabatically throttles, the temperature tends to change as the pressure drops. The adiabatic throttling effect of the gas can be used to complete the cooling treatment process of cryoablation. However, the high-pressure gas throttling method has certain defects in actual use: First, the high-pressure gas has a high risk factor. Since the terminal balloon of cryoablation is generally in the human body, once the gas pressure is too high, it may cause the balloon to rupture, posing a great safety threat to the patient; secondly, high-pressure gas is a consumable and needs to be replenished, which is inconvenient to use; thirdly, the use of the equipment has high requirements for the operator, and it needs to be accompanied by a professional technician during the operation. Summary of the invention

[0007] Therefore, the technical problem to be solved by the present invention is to overcome the defects of the cryoablation device in the prior art, such as high risk factor, rapid consumption of working fluid and inconvenience in use, and to provide a cryoablation device with low risk factor, minimal working fluid loss and easy use.

[0008] Another technical problem to be solved by the present invention is to overcome the defects of the cryoablation method in the prior art, which is high risk factor and difficult to operate, and thus provide a cryoablation method with low risk factor and simple operation.

[0009] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0010] A cryoablation device for locally advanced pancreatic cancer, comprising:

[0011] A cryoballoon, in which a cooling medium flows, is suitable for contacting human tissue and cryoablating the tissue;

[0012] The catheter is connected to the cryoballoon and has a medium input end and a medium output end, and is suitable for inputting and outputting a cold medium into and out of the cryoballoon;

[0013] A medium storage tank, in which a cooling medium is stored;

[0014] A medium supply pipeline, one end of which is connected to the medium storage tank, and the other end of which is connected to the medium input end of the conduit;

[0015] A medium recovery pipeline, one end of which is connected to the medium storage tank, and the other end of which is connected to the medium output end of the conduit;

[0016] The refrigeration component is connected in series with the medium supply pipeline and is suitable for refrigerating and exchanging heat with the cooling medium in the medium supply pipeline.

[0017] As a preferred technical solution, the refrigeration component includes:

[0018] A cold generating device, used for generating cold;

[0019] A first cold exchange device is installed on the medium supply pipeline, the cold generating device provides cold energy to the first cold exchange device, and the first cold exchange device is used to cool and exchange heat with the cold medium passing through the first cold exchange device;

[0020] As a preferred technical solution, the refrigeration assembly further includes:

[0021] The second cold exchange device has a hot fluid channel installed on the medium supply pipeline and a cold fluid channel installed on the medium recovery pipeline, and cold exchange occurs between the cold fluid channel and the hot fluid channel to pre-cool the cold medium flowing through the hot fluid channel;

[0022] The hot fluid channel is connected between the medium storage tank and the first cold exchange device.

[0023] As a preferred technical solution, it also includes:

[0024] A bypass pipe, wherein the bypass pipe is connected to the medium supply pipeline and the medium recovery pipeline, and the medium supply pipeline and the medium recovery pipeline form a precooling loop connected in series with the medium storage tank and the first cooling capacity exchange device;

[0025] The bypass pipe is connected to the medium supply pipeline via a first three-way valve.

[0026] As a preferred technical solution, the refrigeration assembly further includes:

[0027] The cold storage device is installed on the medium recovery pipeline, connected with the first cold exchange device through a bypass pipe, and is suitable for storing the cold energy flowing out of the first cold exchange device.

[0028] As a preferred technical solution, the refrigeration assembly further includes:

[0029] The heat-insulating device has a heat-insulating cavity suitable for reducing or isolating heat conduction with the outside, and the cold output ends of the first cold exchange device, the second cold exchange device, the cold storage device and the cold generating device are located in the heat-insulating cavity.

[0030] As a preferred technical solution, the heat insulation device is a box body, and a vacuum device connected to the heat insulation cavity is installed on the heat insulation device.

[0031] As a preferred technical solution, the heat insulation device is a box, and the heat insulation cavity is filled with insulating material.

[0032] As a preferred technical solution, it also includes a rewarming circuit, which is used to transport the cold-carrying medium in the medium storage tank to the medium input end of the catheter in the cryoablation device.

[0033] As a preferred technical solution, the temperature recovery circuit includes:

[0034] Rewarming tube;

[0035] The medium inlet end of the rewarming pipe is connected to the side of the medium supply pipeline that does not enter the first cold exchange device by a second three-way valve.

[0036] As a preferred technical solution, it also includes a rewarming circuit, which is used to heat the cold-carrying medium in the medium storage tank and then transport it to the medium input end of the catheter in the cryoablation device.

[0037] As a preferred technical solution, the temperature recovery circuit includes:

[0038] A re-temperature pipe, on which a temperature-raising device is connected in series;

[0039] The medium inlet end of the temperature recovery pipe is connected to the upstream of the medium inlet port entering the hot fluid channel by means of a second three-way valve.

[0040] As a preferred technical solution, the temperature recovery circuit further includes:

[0041] The rewarming reflux pipeline is used to connect the medium output end of the catheter in the cryoablation device with the medium storage tank.

[0042] As a preferred technical solution, the rewarming reflux pipeline includes:

[0043] The reheating reflux pipe has two ends connected to the medium recovery pipeline and is connected in parallel with the second cooling capacity exchange device;

[0044] The medium inlet end of the rewarming reflux pipe is connected to the medium supply pipeline by means of a third three-way valve.

[0045] As a preferred technical solution, the refrigeration assembly further includes:

[0046] The heat insulation device has a heat insulation cavity suitable for reducing or isolating heat conduction with the outside, and the cold output ends of the first cold exchange device, the second cold exchange device, the cold storage device and the cold generation device are located in the heat insulation cavity;

[0047] The re-temperature return pipe is located outside the heat insulation device.

[0048] As a preferred technical solution, a pumping device is connected in series to the medium supply pipeline or the medium recovery pipeline, and the pumping device is suitable for providing power for the flow of the cooling medium.

[0049] A cryoablation method comprises the following steps:

[0050] Pre-cooling, cooling the cooling medium through the cooling generating device

[0051] Ablation, the pre-cooled cold medium is circulated again into the cold generating device for cooling again, and then introduced into the target tissue of the human body, so that the cold medium and the target tissue exchange cold energy, and the target tissue is cooled and then cryoablated;

[0052] Recovering, transporting the cold-carrying medium after exchanging cold with the target tissue out of the human body and transporting it to a medium storage tank;

[0053] Rewarming: Stop introducing the cooled cooling medium into the human body to warm up the targeted tissue.

[0054] As a preferred technical solution, in the recovery step, the cold-carrying medium is transported out of the human body after exchanging cold with the target tissue, and the residual cold in the cold-carrying medium is used to exchange cold with the cold-carrying medium flowing out of the medium storage tank in the second cold exchange device, so that the cold-carrying medium that has not yet entered the first cold exchange device is cooled and then transported to the first cold exchange device.

[0055] As a preferred technical solution, a portion of the cold is stored in the pre-cooling stage, transported to the cooling medium recovered from the conduit, and exchanged with the cooling medium flowing out of the medium storage tank in the second cooling exchange device.

[0056] As a preferred technical solution, in the rewarming step, the cooling medium is circulated through the heating device to heat the cooling medium, and then the heated cooling medium is introduced into the targeted tissue of the human body, so that heat is exchanged between the cooling medium and the targeted tissue, thereby heating the cooled targeted tissue.

[0057] As a preferred technical solution, in the rewarming step, an unrefrigerated cooling medium is input into the human body, so that the target tissue is heated up after heat exchange with the unrefrigerated cooling medium.

[0058] The technical solution of the present invention has the following advantages:

[0059] 1. The cryoablation device provided by the present invention includes a cryoballoon, a catheter, a medium storage tank, a medium supply pipeline, a medium recovery pipeline and a refrigeration component; a cold medium circulates in the cryoballoon, which is suitable for contacting with human tissue and cryoablating it; the catheter is connected to the cryoballoon, has a medium input end and a medium output end, and is suitable for inputting and outputting the cold medium into and out of the cryoballoon; the medium storage tank stores the cold medium, which is a low-pressure liquid or gas or a gas-liquid mixture; one end of the medium supply pipeline is connected to the medium storage tank, and the other end is connected to the medium input end of the catheter; one end of the medium recovery pipeline is connected to the medium storage tank, and the other end is connected to the medium output end of the catheter; the refrigeration component is connected in series with the medium supply pipeline, which is suitable for providing cold to the cold medium in the medium supply pipeline. During cryoablation, the cold medium flows along the following path: after flowing out from the medium storage tank along the medium supply pipeline, the temperature of the cold medium drops through the refrigeration component, and then enters the medium input end of the catheter, and then flows into the cryoballoon to contact the target tissue through the balloon, and then flows out from the medium output end of the catheter to the medium recovery pipeline, and finally returns to the medium storage tank to complete a cycle. In the above process, since the original high-pressure gas is replaced with a cold medium, the cold medium body is directly cooled and refrigerated to meet the low temperature requirements of cryoablation. Compared with high-pressure gas, the cold medium is less likely to explode, so it can effectively reduce the risk factor of the cryoablation device when in use. At the same time, since the cold medium can be recycled, there is no need to replenish high-pressure gas during use, which improves its convenience during use. In addition, the cooling method of the low-pressure cold medium is single, and it only relies on the refrigeration component for cooling. Therefore, its cooling process is easier to control than the cooling method that relies on high-pressure gas throttling, thereby effectively reducing its operating difficulty. The surgeon can perform the entire operation without the accompaniment of a professional technician.

[0060] 2. In the cryoablation device provided by the present invention, the refrigeration component also includes a second cold exchange device, which has a hot fluid channel installed on the medium supply pipeline and a cold fluid channel installed on the medium recovery pipeline. Cold exchange occurs between the cold fluid channel and the hot fluid channel to pre-cool the cold-carrying medium flowing through the hot fluid channel; the hot fluid channel is connected between the medium storage tank and the first cold exchange device. When performing cryoablation, the medium supply pipeline, medium recovery pipeline, catheter of the cryoablation system and cryoballoon are used to circulate the cold medium. During the flow process, the cold generated at the cold generating device is transported to the medium supply pipeline through the first cold exchange device, and then transported to the human body through the catheter to perform cryoablation on the target tissue. The cold medium that has exchanged cold with the target tissue then flows from the catheter to the medium recovery pipeline. At this time, the cold medium still has some cold remaining. Then, when the cold medium flows through the medium recovery pipeline, due to the presence of the second cold exchange device, the remaining cold in the cold medium will be transferred to the cold medium in the medium supply pipeline through the second cold exchange device, so that the cold medium at this location is pre-cooled. In the above process, since the second cold exchange device is located upstream of the first cold exchange device on the medium supply pipeline, the temperature of the cold medium in the medium supply pipeline at this location is higher than the temperature in the medium recovery pipeline, thereby ensuring that the cold is transferred from the medium recovery pipeline to the medium supply pipeline. Through the above process, the residual cold energy of the cooling medium in the medium recovery pipeline can pre-cool the cooling medium and reduce the initial temperature of the cooling medium when it enters the first cooling exchange device. Then, under the same cooling exchange capacity, the pre-cooled cooling medium can reach a lower temperature, thereby making it more likely for the cryoablation method of directly cooling the low-pressure medium to reach the temperature required for cryoablation, while also improving the utilization efficiency of the cooling energy.

[0061] 3. The cryoablation device provided by the present invention also includes a bypass pipe, which is connected to the medium supply pipeline and the medium recovery pipeline, and the medium supply pipeline and the medium recovery pipeline form a pre-cooling circuit that is connected in series with the medium storage tank and the first cold exchange device; and the bypass pipe is connected to the medium supply pipeline through a first three-way valve. By using the bypass pipe, the refrigerant can be pre-cooled before being introduced into the human body for cryoablation. During the pre-cooling stage, the refrigerant comes out of the medium storage tank and flows through the medium supply pipeline, the first cold exchange device, the bypass pipe and the medium recovery pipeline in sequence, and finally returns to the medium storage tank. The temperature of the refrigerant is reduced after pre-cooling, and has a lower initial temperature when entering the cryoablation stage. After cooling by the first cold exchange device, it is easier to reach the low temperature required for cryoablation. Therefore, this can further increase the possibility that the refrigerant of the cryoablation device reaches the required temperature for cryoablation.

[0062] 4. The cryoablation device provided by the present invention also includes a cold storage device, which is installed on the medium recovery pipeline, connected to the first cold exchange device by a bypass pipe, and suitable for storing the cold flowing out of the first cold exchange device. In the pre-cooling stage, the cold storage device can store a part of the cold brought by the cold-carrying medium. After the cryoablation stage begins, these stored cold can pre-cool the cold-carrying medium retained from the human body, so that the temperature difference between the cold fluid channel and the hot fluid channel at the second cold exchange device is increased, and the cold exchange rate at the second cold exchange device is increased, thereby further reducing the temperature of the cold-carrying medium in the medium supply pipeline. These cold-carrying media that have been pre-cooled can reach a lower temperature after the first cold exchange device undergoes final cooling. Therefore, this can further ensure that the cryoablation device can reach the low temperature required for cryoablation, and can further improve the utilization efficiency of cold and reduce cold waste.

[0063] 5. The cryoablation device provided by the present invention also includes a heat insulation device, which has a heat insulation cavity suitable for reducing or isolating heat conduction with the outside, and the cold output ends of the first cold exchange device, the second cold exchange device, the cold storage device and the cold generating device are located in the heat insulation cavity. The use of the heat insulation device can avoid the loss of cold in the cold exchange process, and the heat preservation effect of the cold storage device is also better, avoiding the loss of cold in the process of storing cold in the cold storage device.

[0064] 6. In the cryoablation device provided by the present invention, the heat insulation device is a box, and a vacuum device connected to the heat insulation cavity is installed on the heat insulation device. The heat insulation cavity close to the vacuum state can further reduce the loss rate of cold energy, so that the cryoablation device can further improve the utilization efficiency of cold energy.

[0065] 7. The cryoablation device provided by the present invention also includes a rewarming circuit, which is used to heat the cold medium in the storage tank and then transport it to the medium input end of the catheter in the cryoablation device. In cryoablation, the target tissue must be rewarmed after freezing. An ideal rewarming process can improve the surgical effect of cryoablation and reduce the probability of postoperative complications. The rewarming circuit provided in the present invention can heat the cold medium and transport it to the target tissue through a catheter. This separately set rewarming circuit can not only meet the needs of cryoablation for rewarming, but also is very conducive to more precise control of the temperature, process and time of rewarming, thereby improving the surgical cure rate and reducing postoperative complications.

[0066] 8. In the cryoablation device provided by the present invention, the rewarming circuit includes a rewarming tube, and a heating device is connected in series to the rewarming tube; the medium inlet end of the rewarming tube is connected to the upstream of the inlet into the hot fluid channel by a second three-way valve. After the rewarming tube is connected to the upstream of the second cold exchange device on the medium supply pipeline, the rewarming tube and the first cold exchange device and the second cold exchange device are connected in parallel, and the pipelines used for heating the coolant and the pipelines used for cooling are independent of each other. Therefore, it is possible to avoid the residual cold of the first cold exchange device and the second cold exchange device from interfering with the heating process of the coolant during the rewarming stage, reduce the interference factors of the rewarming process, and make the control of the rewarming process easier to control.

[0067] 9. In the cryoablation device provided by the present invention, the rewarming circuit also includes a rewarming reflux pipeline, which is used to connect the medium output end of the catheter in the cryoablation device with the medium storage tank. The separately arranged rewarming reflux pipeline can make the rewarming process form a separate rewarming circuit consisting of the medium storage tank, the rewarming tube, the cryoablation device, and the rewarming reflux pipeline, thereby further reducing interference factors in the rewarming process and making the rewarming process control more accurate.

[0068] 10. The cryoablation device provided by the present invention also includes a heat insulation device, the heat insulation device has a heat insulation cavity suitable for reducing or isolating heat conduction with the outside, the cold output ends of the first cold exchange device, the second cold exchange device, the cold storage device and the cold generating device are located in the heat insulation cavity; the rewarming return pipe is located outside the heat insulation device. After the rewarming return pipe is arranged outside the heat insulation device, it can prevent the rewarming return pipe from taking away the cold in the cold storage device or the second cold exchange device when transporting the rewarmed cold medium, thereby improving the utilization rate of the cold.

[0069] 11. The technical solution provided by the present invention also includes a cryoablation method, including the following steps: precooling, passing a low-pressure cold-carrying medium into a cold-energy generating device for cooling in a cold circulation; ablation, passing the precooled cold-carrying medium into a cold-energy generating device in a circulation, and then passing it into the target tissue of the human body, so that the cold-carrying medium and the target tissue exchange cold energy, and the target tissue is cooled and then cryoablated; recycling, the cold-carrying medium after cold energy exchange with the target tissue is transported out of the human body and transported to a storage tank; rewarming, rewarming, stopping the introduction of the cooled cold-carrying medium into the human body, so that the target tissue is heated. In the above steps, due to the precooling step, the cold-carrying medium has a lower temperature after precooling, so that it has a lower initial temperature during the cooling process in the ablation stage, and thus the temperature that can be reached in the end will be lower. Compared with the method of directly cooling the cold-carrying medium and then passing it into the human body in the prior art, the cold-carrying medium in this method is easier to reach the low temperature required for cryoablation.

[0070] 12. In the cryoablation method provided by the present invention, in the recovery step, the cold medium after exchanging cold with the target tissue is transported out of the human body, and the residual cold in the cold medium is used to exchange cold with the cold medium that has not been introduced into the cold generating device, so that the cold medium that has not been introduced into the cold generating device is cooled and then transported to the cold generating device. In the above steps, the residual cold of the cold medium in the medium recovery pipeline can be reused, which can improve the utilization efficiency of cold and reduce the power burden of the cold generating device.

[0071] 13. In the cryoablation method provided by the present invention, a portion of cold energy is stored in the precooling stage, and the cold energy is delivered to the cold medium delivered from the human body, so that the cold medium delivered from the human body is cooled. Through the above steps, the pre-stored cold energy can reduce the temperature of the cold medium after being delivered to the medium recovery pipeline, thereby making the temperature difference in the process of using the residual cold energy of the delivered cold medium to cool the uninput cold medium in the recovery step larger, thereby increasing the cold energy exchange rate between the two, making the temperature of the cold medium not input into the human body lower, and making it easier to reach the temperature required for cryoablation under the refrigeration of the cold energy generating device.

[0072] In summary, the cryoablation device and cryoablation method provided by the present invention have low risk factors, simple operation, and convenient use. They also have the advantages of high cold utilization efficiency and precise temperature control. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0074] Figure 1 This is a schematic diagram of the structure of the cryoablation device provided in Example 1 of the present invention;

[0075] Figure 2 for Figure 1 The schematic diagram of the flow direction of the cooling medium of the cryoablation device in the precooling stage is shown;

[0076] Figure 3 for Figure 1 A schematic diagram of the flow direction of the cooling medium of the cryoablation device during the cryoablation stage;

[0077] Figure 4 for Figure 1 A schematic diagram of the flow direction of the cooling medium of the cryoablation device during the rewarming stage;

[0078] Figure 5 This is a flow chart of the cryoablation method provided in Example 3 of the present invention;

[0079] Description of reference numerals:

[0080] 1-medium storage tank, 2-medium supply pipeline, 3-medium recovery pipeline, 4-cold generating device, 5-first cold exchange device, 6-second cold exchange device, 7-conduit, 8-freezing balloon, 9-bypass pipe, 10-first three-way valve, 11-cold storage device, 12-insulation device, 13-insulation chamber, 14-vacuum device, 15-rewarming pipe, 16-warming device, 17-second three-way valve, 18-rewarming reflux pipe, 19-third three-way valve, 20-pumping device, 21-flow meter, 22-thermometer, 23-check valve, 24-radiator. DETAILED DESCRIPTION

[0081] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0082] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0083] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0084] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0085] Embodiment 1:

[0086] like Figures 1 to 4 As shown, it is embodiment 1 of the present invention, which provides a cryoablation device for locally advanced pancreatic cancer, including a cryoballoon 8, a catheter 7, a medium storage tank 1, a medium supply pipeline 2, a medium recovery pipeline 3 and a refrigeration component; a cooling medium flows in the freezing balloon 8, which is suitable for contacting with human tissue and cryoablating it; the catheter 7 is connected to the freezing balloon 8, and has a medium input end and a medium output end, which is suitable for inputting and outputting the cooling medium into and out of the freezing balloon 8; the cooling medium is stored in the medium storage tank 1, and the cooling medium is a low-pressure medium; one end of the medium supply pipeline 2 is connected to the medium storage tank 1, and the other end is connected to the liquid inlet end of the catheter 7; one end of the medium recovery pipeline 3 is connected to the medium storage tank 1, and the other end is connected to the liquid outlet end of the catheter 7; the refrigeration component is connected in series with the medium supply pipeline 2, which is suitable for cooling and exchanging heat with the cooling medium in the medium supply pipeline 2.

[0087] During the cryoablation procedure, the cold medium flows along the following path: after flowing out from the medium storage tank 1 along the medium supply pipeline 2, the temperature of the cold medium drops through the refrigeration component, and then enters the medium input end of the catheter 7, and then flows into the cryoballoon 8 to contact the target tissue through the balloon, and then flows out from the medium output end of the catheter 7 to the medium recovery pipeline 3, and finally returns to the medium storage tank 1 to complete a cycle. In the above process, since the original high-pressure gas is replaced with the cold medium, the cold medium is directly refrigerated, which is less likely to explode than the high-pressure gas, thereby effectively reducing the risk factor of the cryoablation device when in use. At the same time, since the low-pressure cold medium can be recycled, there is no need to supplement the high-pressure gas during use, which improves its convenience during use. In addition, the low-pressure cold medium has a single cooling method, which only relies on the refrigeration component for cooling, so its cooling process is easier to control than the cooling method that relies on high-pressure gas throttling, thereby effectively reducing its operating difficulty, and the surgeon can perform the entire operation without the accompaniment of a professional technician.

[0088] As a specific embodiment of the refrigeration component, the refrigeration component includes a cold energy generating device 4, a first cold energy exchange device 5 and a second cold energy exchange device 6. The cold energy generating device 4 is used to provide cold energy; the first cold energy exchange device 5 is installed on the medium supply pipeline 2, and the cold energy generating device 4 provides cold energy to the first cold energy exchange device 5, and the first cold energy exchange device 5 is used to perform refrigeration and heat exchange on the cold medium passing through the first cold energy exchange device 5; the second cold energy exchange device 6 has a hot fluid channel installed on the medium supply pipeline 2 and a cold fluid channel installed on the medium recovery pipeline 3, and cold energy is exchanged between the cold fluid channel and the hot fluid channel, and the cold medium flowing through the hot fluid channel is precooled; the hot fluid channel is connected between the medium storage tank 1 and the first cold energy exchange device 5.

[0089] When the above-mentioned refrigeration components participate in cryoablation, the medium supply pipeline 2, the medium recovery pipeline 3, the catheter 7 of the cryoablation system and the cryoballoon 8 are used to circulate the cold medium. During the flow, the cold generated at the cold generating device 4 is transported to the medium supply pipeline 2 through the first cold exchange device 5, and then transported to the human body through the catheter 7 to perform cryoablation on the targeted tissue. The cold medium that has exchanged cold with the targeted tissue then flows from the catheter 7 to the medium recovery pipeline 3. At this time, some cold is still left in the cold medium. Subsequently, when the cold medium flows through the medium recovery pipeline 3, due to the presence of the second cold exchange device 6, the remaining cold in the cold medium will be transferred to the cold medium in the medium supply pipeline 2 through the second cold exchange device 6, so that the cold medium at this location is pre-cooled.

[0090] In the above process, since the second cold exchange device 6 is located upstream of the first cold exchange device 5 on the medium supply pipeline 2, the temperature of the cold medium in the medium supply pipeline 2 is higher than the temperature in the medium recovery pipeline 3, thereby ensuring that the cold is transferred from the medium recovery pipeline 3 to the medium supply pipeline 2. Through the above process, the residual cold of the cold medium in the medium recovery pipeline 3 can pre-cool the cold medium, reduce the initial temperature of the cold medium when it enters the first cold exchange device 5, and then under the same cold exchange amount, the pre-cooled cold medium can reach a lower temperature, thereby making it more likely that the cryoablation method of directly cooling the low-pressure medium can reach the temperature required for cryoablation, while also improving the utilization efficiency of the cold.

[0091] Specifically, the cold generating device 4 in this embodiment is a micro ultra-low temperature refrigerator that can provide a cold source below -120°C, which can be a pulse tube, Stirling, mixed working fluid throttling, thermoacoustic, etc., and the number can be one or more. When multiple units work together, the combination mode can be series or parallel. The cold medium in this embodiment is a medium with a low freezing point, such as anhydrous ethanol.

[0092] In order to further reduce the lowest temperature that the cooling medium can reach, a bypass pipe 9 is also included. The bypass pipe 9 is connected to the medium supply pipeline 2 and the medium recovery pipeline 3, and the medium supply pipeline 2 and the medium recovery pipeline 3 form a pre-cooling circuit of the series medium storage tank 1 and the first cold exchange device 5; and the bypass pipe 9 is connected to the medium supply pipeline 2 through a first three-way valve 10.

[0093] By using the bypass pipe 9, the refrigerant can be precooled before entering the human body for cryoablation. In the precooling stage, the refrigerant comes out of the medium storage tank 1 and flows through the medium supply pipeline 2, the first cold exchange device 5, the bypass pipe 9 and the medium recovery pipeline 3 in sequence, and finally returns to the medium storage tank 1. The temperature of the refrigerant is reduced after precooling, and it has a lower initial temperature when entering the cryoablation stage. After the first cold exchange device 5 cools down, it is easier to reach the low temperature required for cryoablation. Therefore, this can further increase the possibility that the cryoablation device is the refrigerant medium that reaches the temperature required for cryoablation.

[0094] As an improved implementation of the cryoablation device, it also includes a cold storage device 11, which is installed on the medium recovery pipeline 3, connected to the first cold exchange device 5 through the bypass pipe 9, and is suitable for storing the cold flowing out of the first cold exchange device 5. In this embodiment, the cold storage device 11 is specifically a box filled with a cold storage medium with a high specific heat capacity, and the medium recovery pipeline 3 passes through the cold storage device 11, and uses the side wall of the pipeline to exchange cold with the cold storage medium in the cold storage device 11.

[0095] In the pre-cooling stage, the cold storage device 11 can store a part of the cold brought by the cold medium. After the cryoablation stage begins, the stored cold can pre-cool the cold medium left from the human body, so that the temperature difference between the cold fluid channel and the hot fluid channel at the second cold exchange device 6 increases, and the cold exchange rate at the second cold exchange device 6 is increased, thereby further reducing the temperature of the cold medium in the medium supply pipeline 2. These cold media that have been pre-cooled can reach a lower temperature after the first cold exchange device 5 is finally cooled. Therefore, this can further ensure that the cryoablation device can reach the low temperature required for cryoablation, and can further improve the utilization efficiency of cold and reduce cold waste.

[0096] In order to reduce the loss of cold, a heat insulation device 12 is also included, and the heat insulation device 12 has a heat insulation cavity 13 suitable for reducing or isolating heat conduction with the outside, and the cold output ends of the first cold exchange device 5, the second cold exchange device 6, the cold storage device 11 and the cold generating device 4 are located in the heat insulation cavity 13. The use of the heat insulation device 12 can avoid the loss of cold in the cold exchange process, and the heat preservation effect of the cold storage device 11 is also better, avoiding the loss of cold in the process of storing cold in the cold storage device 11.

[0097] Specifically, the heat insulating device 12 is a box, and a vacuum device 14 connected to the heat insulating cavity 13 is installed on the heat insulating device 12. The heat insulating cavity 13 close to the vacuum state can further reduce the loss rate of cold energy, so that the cryoablation device can further improve the utilization efficiency of cold energy. The vacuum device 14 is specifically a small vacuum pump.

[0098] As another alternative embodiment of the heat insulation device, the heat insulation device 12 is a box, and the heat insulation cavity 13 is filled with a heat insulation material, where the heat insulation material can be a polyurethane foam material, aerogel or other heat insulation materials.

[0099] In order to meet the need of rewarming the target tissue after freezing in cryoablation, the present embodiment also includes a rewarming circuit, which is used to heat the cold medium in the storage tank and then transport it to the medium input end of the catheter 7 in the cryoablation device. In cryoablation, the target tissue after freezing needs to be rewarmed. An ideal rewarming process can improve the surgical effect of cryoablation and reduce the probability of postoperative complications. The rewarming circuit provided in the present invention can heat the cold medium and transport it to the target tissue through the catheter 7. This separately set rewarming circuit can not only meet the need for rewarming in cryoablation, but also is very conducive to more precise control of the temperature, process and time of rewarming, thereby improving the surgical cure rate and reducing postoperative complications.

[0100] Specifically, the rewarming circuit includes a rewarming pipe 15, and a heating device 16 is connected in series to the rewarming pipe 15; the medium inlet end of the rewarming pipe 15 is connected to the upstream of the inlet of the hot fluid channel by a second three-way valve 17. After the rewarming pipe 15 is connected to the upstream of the second cold exchange device 6 on the medium supply pipeline 2, the rewarming pipe 15 and the first cold exchange device 5 and the second cold exchange device 6 are connected in parallel, and the pipelines used for heating the refrigerant and the pipelines used for cooling are independent of each other. Therefore, it is possible to avoid the residual cold of the first cold exchange device 5 and the second cold exchange device 6 from interfering with the heating process of the refrigerant during the rewarming stage, reduce the interference factors of the rewarming process, and make the control of the rewarming process easier to control.

[0101] As an alternative embodiment of the above-mentioned rewarming circuit, the rewarming circuit includes: a rewarming tube 15; the medium inlet end of the rewarming tube 15 is connected to the side of the medium supply pipeline 2 that does not enter the first cold exchange device 5 by a second three-way valve 17. In this alternative embodiment, there is no series heating device on the rewarming circuit, but only the uncooled cold medium is introduced into the catheter to participate in the rewarming process, and the body's own heat is used for rewarming. This makes the temperature rise of the target tissue more gentle and reduces the damage of cryoablation to healthy tissue.

[0102] As a further improvement of the rewarming circuit, the rewarming circuit also includes a rewarming reflux pipeline, which is used to connect the medium output end of the catheter 7 in the cryoablation device with the recovery port connected to the medium storage tank 1. The separately provided rewarming reflux pipeline can make the rewarming process form a separate rewarming circuit composed of the medium storage tank 1, the rewarming tube 15, the cryoablation device, and the rewarming reflux pipeline, thereby further reducing interference factors in the rewarming process and making the rewarming process control more accurate.

[0103] Specifically, the rewarming return pipeline includes a rewarming return pipe 18, both ends of which are connected to the medium recovery pipeline 3 and connected in parallel to the second cold exchange device 6; the medium inlet end of the rewarming return pipe 18 is connected to the medium supply pipeline 2 by a third three-way valve 19. Further, the rewarming return pipe 18 is located outside the insulation device 12. After the rewarming return pipe 18 is arranged outside the insulation device 12, it can be prevented that the rewarming return pipe 18 takes away the cold in the cold storage device 11 or the second cold exchange device 6 when transporting the rewarmed cold-carrying medium, thereby improving the utilization rate of the cold.

[0104] In order to ensure the smooth circulation of the cooling medium, a pumping device 20 is connected in series to the medium supply pipeline 2 or the medium recovery pipeline 3, and the pumping device 20 is suitable for providing power for the flow of the cooling medium.

[0105] The cryoablation device provided in this embodiment also includes an operating device. The operating device includes a handle and an actuator, which is used to operate the catheter 7 to reach the ablation target tissue. When performing cryoablation, the catheter 7 is a pipeline for transporting low-temperature cold medium. It is made of a material with a certain toughness, a small thermal conductivity, and physiological compatibility. It has multiple flow channels inside, which are the inlet and outlet flow channels of the cold medium, the functional channel and the isolation cavity. The inlet and outlet flow channels of the cold medium are distributed on both sides to insulate the inlet and outlet fluids to avoid thermal short circuits. The functional channel is located in the center of the catheter 7 and is used for the routing of functional components such as sensors and guide wires. The isolation cavity is distributed at both ends of the cold medium flow channel to further reduce the heat exchange of the inlet and outlet fluids. The outside of the catheter 7 is wrapped with an insulating material to reduce the heat transfer between the cold medium in the catheter 7 and the external human tissue, on the one hand to reduce the heat leakage of the cold medium, and on the other hand to avoid the freezing of tissues caused by the excessively low temperature of the outer wall of the catheter 7. The cryoballoon 8 is used to perform cryoablation on the target tissue, and has a medium inlet and a medium outlet inside, wherein the medium inlet is connected to the inlet channel of the catheter 7, and the medium outlet is connected to the outlet channel of the catheter 7. After the balloon contacts the tissue, the cold medium exchanges heat with the tissue through the balloon wall.

[0106] Embodiment 2:

[0107] like Figure 5 As shown, this is Example 2 provided by the present invention. This embodiment provides a cryoablation method. In this method, a low-pressure medium is used to carry out cryoablation of a target tissue of a human body by directly introducing a cold medium into the human body after being cooled. The method specifically includes the following steps:

[0108] Precooling: The low-pressure cooling medium is circulated into the cooling generating device 4 for cooling.

[0109] Ablation, the pre-cooled cooling medium is circulated into the cooling generating device 4, and then introduced into the target tissue of the human body, so that the cooling medium and the target tissue exchange cold energy, and the target tissue is cooled and then cryoablated.

[0110] Recover and transport the cooling medium after exchanging cold with the target tissue out of the human body and into a storage tank.

[0111] Rewarming: Stop introducing the cooled cooling medium into the human body, and allow the target tissue to warm up.

[0112] In the above steps, due to the pre-cooling step, the cooling medium has a lower temperature after pre-cooling, so that it has a lower initial temperature during the cooling process in the ablation stage, and thus the temperature that can be reached in the end will be lower. Compared with the method of directly cooling the cooling medium and then passing it into the human body in the prior art, the cooling medium in this method is easier to reach the low temperature required for cryoablation.

[0113] In the recovery step, the cold medium after exchanging cold with the target tissue is transported out of the human body, and the residual cold in the cold medium is used to exchange cold with the cold medium that has not been passed into the cold generating device 4, so that the cold medium that has not been passed into the cold generating device 4 is cooled and then transported to the cold generating device 4. In the recovery step, the residual cold of the cold medium in the medium recovery pipeline 3 can be reused, which can improve the utilization efficiency of cold and reduce the power burden of the cold generating device 4.

[0114] In the pre-cooling step, a portion of the cold is stored and delivered to the cold medium delivered from the human body, so that the cold medium delivered from the human body is cooled. Through the above steps, the pre-stored cold can reduce the temperature of the cold medium after being delivered to the medium recovery pipeline 3, thereby making the temperature difference in the process of using the residual cold of the delivered cold medium to cool the uninput cold medium in the recovery step larger, thereby increasing the cold exchange rate between the two, making the temperature of the cold medium not input into the human body lower, and making it easier to reach the temperature required for cryoablation under the refrigeration of the cold generating device 4.

[0115] As a specific implementation of the rewarming step, in the rewarming step, the cooling medium is circulated through the heating device (16) to heat the cooling medium, and then the heated cooling medium is introduced into the target tissue of the human body, so that heat exchange occurs between the cooling medium and the target tissue, thereby heating the cooled target tissue.

[0116] As an alternative implementation of the above-mentioned rewarming step, in the rewarming step, an unrefrigerated cooling medium may also be introduced into the human body, so that the target tissue is heated after heat exchange with the unrefrigerated cooling medium.

[0117] In combination with the cryoablation device in Example 1, the specific process of the cryoablation method in this embodiment is as follows:

[0118] Precooling stage, see Figure 2 , the cold generating device 4 and the pumping device 20 are turned on, and the three three-way valves are adjusted to make the cooling medium flow according to the following process: after the room temperature cooling medium flows out of the medium storage tank 1, it passes through the flow meter, the pumping device 20, and the flow regulating valve and enters the insulation device 12, passes through the second cooling exchange device 6 and the returning cooling medium for pre-cooling by heat exchange, enters the first cooling exchange device 5 for cooling, flows through the bypass pipe 9 and enters the cold storage device 11, stores part of the cold in the cold storage device 11, and then flows back to the second cooling exchange device 6 to pre-cool the cooling medium retained from the medium storage tank 1, and finally flows out of the insulation device 12, and finally returns to the medium storage tank 1.

[0119] After the pre-cooling cycle is carried out for about 20 minutes, the cooling medium drops to minus 80-100℃.

[0120] During the ablation phase, Figure 3 After precooling is completed, adjust the three three-way valves to make the cooling medium flow according to the following process: after passing through the flow meter, the pumping device 20, and the flow regulating valve, it enters the insulation device 12, passes through the second cold exchange device 6 to exchange heat with the returning cooling medium, and then enters the first cold exchange device 5 for cooling. After being cooled by the first cold exchange device 5, the cooling medium flows out of the insulation device 12, enters the catheter 7, and then enters the freezing balloon 8 for ablation, and then flows out of the catheter 7, returns to the insulation device 12, and flows through the cold storage device 11. At this time, the temperature of the cooling medium is higher than the temperature of the heat storage medium in the cold storage device 11. The cooling medium releases heat to the heat storage medium, and the temperature decreases. Then, it enters the second cold exchange device 6, exchanges cold with the cooling medium flowing out of the medium storage tank 1, and then exits the insulation device 12 and returns to the medium storage tank 1.

[0121] Rewarming phase, see Figure 4 After cryoablation is completed, adjust the three three-way valves to make the cooling medium flow according to the following process: the cooling medium first comes out of the medium storage tank 1, flows through the flow meter, the pumping device 20 and the flow regulating valve, enters the heating device 16, is heated to 37°C by the heating device 16, and then enters the catheter 7 through the rewarming tube 15 to heat and rewarm the ablated tissue. After flowing out of the catheter 7, it passes through the third three-way valve 10, flows through the rewarming reflux tube 18, and then returns to the medium storage tank 1.

[0122] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A cryoablation device for locally advanced pancreatic cancer, characterized in that: include: A cryoballoon (8) in which a cooling medium flows, and is suitable for contacting human tissue and performing cryoablation on the tissue; The catheter (7) is connected to the cryoballoon (8), has a medium input end and a medium output end, and is suitable for inputting and outputting a cold medium into and out of the cryoballoon (8); A medium storage tank (1) storing a cooling medium; A medium supply pipeline (2), one end of which is connected to the medium storage tank (1), and the other end of which is connected to the medium input end of the conduit (7); A medium recovery pipeline (3), one end of which is connected to the medium storage tank (1), and the other end of which is connected to the medium output end of the conduit (7); A refrigeration component, comprising a cold energy generating device (4) and a first cold energy exchange device (5), wherein the refrigeration component is connected in series with a medium supply pipeline (2) and is suitable for performing refrigeration and heat exchange on a cold medium in the medium supply pipeline (2); the first cold energy exchange device (5) is installed on the medium supply pipeline (2), the cold energy generating device (4) provides cold energy to the first cold energy exchange device (5), and the first cold energy exchange device (5) is used for performing refrigeration and heat exchange on a cold medium passing through the first cold energy exchange device (5); A bypass pipe (9), wherein the bypass pipe (9) is connected to the medium supply pipeline (2) and the medium recovery pipeline (3), and the medium supply pipeline (2) and the medium recovery pipeline (3) form a precooling circuit that is connected in series with the medium storage tank (1) and the first cold exchange device (5); the bypass pipe (9) is connected to the medium supply pipeline (2) via a first three-way valve (10).

2. The cryoablation device for locally advanced pancreatic cancer according to claim 1, characterized in that: The refrigeration assembly also includes: The second cold exchange device (6) comprises a hot fluid channel installed on the medium supply pipeline (2) and a cold fluid channel installed on the medium recovery pipeline (3), wherein cold exchange occurs between the cold fluid channel and the hot fluid channel to pre-cool the cold medium flowing through the hot fluid channel; The hot fluid channel is connected between the medium storage tank (1) and the first cold exchange device (5).

3. The cryoablation device for locally advanced pancreatic cancer according to claim 2, characterized in that: The refrigeration assembly also includes: The cold storage device (11) is installed on the medium recovery pipeline (3), connected to the first cold exchange device (5) via a bypass pipe (9), and is suitable for storing cold energy flowing out of the first cold exchange device (5).

4. The cryoablation device for locally advanced pancreatic cancer according to claim 3, characterized in that: The refrigeration assembly also includes: The heat insulation device (12) has a heat insulation cavity (13) suitable for reducing or isolating heat conduction with the outside, and the cold output ends of the first cold exchange device (5), the second cold exchange device (6), the cold storage device (11) and the cold generation device (4) are located in the heat insulation cavity (13).

5. The cryoablation device for locally advanced pancreatic cancer according to claim 4, characterized in that: The heat insulation device (12) is a box body, and a vacuum device (14) connected to the heat insulation cavity (13) is installed on the heat insulation device (12); The heat insulation device (12) is a box, and the heat insulation cavity (13) is filled with a heat insulation material; It also includes a rewarming circuit, which is used to transport the cold-carrying medium in the medium storage tank (1) to the medium input end of the catheter (7) in the cryoablation device; The rewarming circuit comprises: Rewarming tube (15); The medium inlet end of the reheating pipe (15) is connected to the side of the medium supply pipeline (2) that does not enter the first cold exchange device (5) by means of a second three-way valve (17).

6. The cryoablation device for locally advanced pancreatic cancer according to claim 2, characterized in that: It also includes a rewarming circuit, which is used to heat the cold-carrying medium in the medium storage tank (1) and then transport it to the medium input end of the catheter (7) in the cryoablation device; The rewarming circuit comprises: A re-temperature pipe (15) on which a temperature raising device (16) is connected in series; The medium inlet end of the temperature recovery pipe (15) is connected to the upstream of the medium inlet port entering the hot fluid channel by means of a second three-way valve (17); The rewarming circuit also includes: A rewarming reflux pipeline, used to connect the medium output end of the catheter (7) in the cryoablation device with the medium storage tank (1); The rewarming reflux pipeline comprises: The reheating return pipe (18) is connected to the medium recovery pipeline (3) at both ends and is connected in parallel with the second cooling capacity exchange device (6); The medium inlet end of the rewarming reflux pipe (18) is connected to the medium supply pipeline (2) by means of a third three-way valve (19).

7. The cryoablation device for locally advanced pancreatic cancer according to claim 12, characterized in that: The refrigeration assembly also includes: The heat insulation device (12) has a heat insulation cavity (13) suitable for reducing or isolating heat conduction with the outside, and the cold output ends of the first cold exchange device (5), the second cold exchange device (6), the cold storage device (11) and the cold generation device (4) are located in the heat insulation cavity (13); The reheating reflux pipe (18) is located outside the heat insulation device (12); A pumping device (20) is connected in series to the medium supply pipeline (2) or the medium recovery pipeline (3), and the pumping device (20) is suitable for providing power for the flow of the cooling medium.

8. A cryoablation method, characterized in that: The following steps are involved: Pre-cooling, cooling the cooling medium by circulating it into the cooling generating device (4) for cooling Ablation, the pre-cooled cold medium is circulated again into the cold energy generating device (4) for cooling again, and then introduced into the target tissue of the human body, so that the cold medium and the target tissue exchange cold energy, and the target tissue is cooled and then cryoablated; Recovering, transporting the cold-carrying medium after exchanging cold with the target tissue out of the human body and transporting it to a medium storage tank; Rewarming: Stop introducing the cooled cooling medium into the human body to warm up the targeted tissue.

9. A cryoablation method according to claim 8, characterized in that: In the recovery step, the cold medium after exchanging cold with the target tissue is transported out of the human body, and the remaining cold in the cold medium is used to exchange cold with the cold medium flowing out of the medium storage tank in the second cold exchange device (6), so that the cold medium that has not yet entered the first cold exchange device (5) is cooled and then transported to the first cold exchange device (5).

10. A cryoablation method according to claim 9, characterized in that: In the pre-cooling stage, a portion of the cold is stored, the cold is transported to the cold medium recovered from the conduit (7), and the cold is exchanged with the cold medium flowing out of the medium storage tank in the second cold exchange device (6); In the rewarming step, the cooling medium is circulated through the heating device (16) to heat the cooling medium, and then the heated cooling medium is introduced into the target tissue of the human body, so that the cooling medium and the target tissue exchange heat, thereby heating the cooled target tissue; In the rewarming step, an unrefrigerated cooling medium is input into the human body, so that the target tissue is heated up after heat exchange with the unrefrigerated cooling medium.

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