Composite high and low temperature thermal ablation system

Abstract

This invention relates to a composite high-low temperature cryogenic ablation system, belonging to the field of ablation technology. The composite high-low temperature cryogenic ablation system of this invention includes a working fluid storage tank, a phase separation valve, connecting pipes, ablation needles, and a controller. The connecting pipes are used to connect to the working fluid storage tank, the phase separation valve, and the ablation needles. The controller is connected to the working fluid storage tank, the phase separation valve, and the ablation needles respectively. The controller is configured to adjust the opening of the phase separation valve according to the number and diameter of the ablation needles connected in the connecting pipes, thereby maintaining the phase separation valve at a target temperature.

Description

[0001] This application is a divisional application of CN 202411472318.X, filed on October 22, 2024, entitled "Composite High and Low Temperature Cold and Hot Ablation System and Control Method Thereof". TECHNICAL FIELD

[0002] The present application relates to the field of ablation technology, in particular to a composite high and low temperature cold and hot ablation system. BACKGROUND

[0003] The composite high and low temperature cold and hot ablation system generally can include a working medium storage tank, a connecting pipeline and an ablation needle. After the composite high and low temperature cold and hot ablation system is pre-cooled, the working medium in the working medium storage tank can be delivered to the ablation needle through the connecting pipeline, and the ablation needle can perform an ablation operation. Since the number of ablation needles connected in the connecting pipeline and the diameter of the ablation needle will affect the flow of the working medium in the ablation needle, and then affect the temperature of the working medium, the time required for pre-cooling and ablation operation, the consumption of working medium and the effect of ablation operation are completely different. SUMMARY

[0004] The present application provides a composite high and low temperature cold and hot ablation system, which can achieve the purpose of rapid cooling in the most economical consumption of working medium under various combinations of ablation needles.

[0005] According to a first aspect of the present application, a composite high and low temperature cold and hot ablation system is provided, comprising a working medium storage tank, a phase separation valve, a connecting pipeline, an ablation needle and a controller, the connecting pipeline being used to connect the working medium storage tank, the phase separation valve and the ablation needle, the controller being connected to the working medium storage tank, the phase separation valve and the ablation needle respectively;

[0006] The controller is configured to adjust the opening degree of the phase separation valve according to the number of ablation needles connected in the connecting pipeline and the diameter of the ablation needles connected in the connecting pipeline so that the phase separation valve is maintained at a target temperature.

[0007] In one embodiment, the controller is configured to adjust the opening degree of the phase separation valve to maintain the phase separation valve at a target temperature when the number of ablation needles connected in the connecting pipeline is 1 and the diameter of the ablation needle is <d2, the target temperature of the phase separation valve being T1 to T2.

[0008] When the current temperature of the phase separation valve is ≥T2, the controller adjusts the opening degree of the phase separation valve to 100%;

[0009] When T1≤the current temperature of the phase separation valve <T2, the controller adjusts the opening degree of the phase separation valve to K1.

[0010] When the current temperature of the phase separation valve is less than T1, the controller adjusts the opening of the phase separation valve to 0%, where T1 < T2.

[0011] Where 0% < K1 < 100%.

[0012] In one implementation, K1 satisfies the following expression:

[0013]

[0014] k is a constant, and its value range is 1≤k≤1.2.

[0015] In one embodiment, when the number of ablation needles connected in the connecting pipeline is ≥2 and the diameter of the ablation needle is <d2, the controller adjusts the opening of the phase separation valve to maintain the phase separation valve at a target temperature, the target temperature of the phase separation valve being T2 to T3.

[0016] Wherein, when the current temperature of the phase separation valve is ≥ T3, the controller adjusts the opening degree of the phase separation valve to 100%;

[0017] When T2 ≤ the current temperature of the phase separation valve < T3, the controller adjusts the opening degree of the phase separation valve to K2;

[0018] When the current temperature of the phase separation valve is less than T2, the controller adjusts the opening of the phase separation valve to 0%, where T2 is less than T3.

[0019] Where 0% < K2 < 100%.

[0020] In one implementation, K2 satisfies the following expression:

[0021]

[0022] k is a constant, and its value range is 1≤k≤1.2.

[0023] In one embodiment, the controller is configured to adjust the opening of the phase separation valve to maintain the phase separation valve at a target temperature, T3 to T4, when the number of ablation needles connected in the connecting pipeline is 0, or when the number of ablation needles connected in the connecting pipeline is ≥1 and the diameter of the ablation needle is ≥d2.

[0024] Wherein, when the current temperature of the phase separation valve is ≥ T5, the controller adjusts the opening degree of the phase separation valve to 100%;

[0025] When T4 ≤ the current temperature of the phase separation valve < T5, the controller adjusts the opening degree of the phase separation valve to K3.

[0026] When T3 ≤ the current temperature of the phase separation valve < T4, the controller adjusts the opening degree of the phase separation valve to K4, where K4 > K3;

[0027] When the current temperature of the phase separation valve is ≤ T3, the controller adjusts the opening of the phase separation valve to 0%, where T3 < T4 < T5.

[0028] In one implementation, K3 and K4 respectively satisfy the following expressions:

[0029]

[0030] Where k is a constant, and its value ranges from 1 to k to 1.2.

[0031] In one embodiment, when the number of ablation needles connected in the connecting pipeline is 1 and the diameter of the ablation needle is < d2, if T1 ≤ the current temperature of the phase separation valve is < T2, the controller adjusts the opening degree of the phase separation valve to K1;

[0032] When the number of ablation needles connected in the connecting pipeline is ≥2 and the diameter of the ablation needle is <d2, if T2 ≤ the current temperature of the phase separation valve is <T3, the controller adjusts the opening degree of the phase separation valve to K2; where T1 < T2 < T3,

[0033] Both K1 and K2 are related to the constant k, and the value of the constant k related to K1 is greater than the value of the constant k related to K2.

[0034] In one embodiment, when the number of ablation needles connected in the connecting pipeline is 0, or when the number of ablation needles connected in the connecting pipeline is ≥1 and the diameter of the ablation needle is ≥d2, if T4≤the current temperature of the phase separation valve<T5, the controller adjusts the opening of the phase separation valve to K3; if T3≤the current temperature of the phase separation valve<T4, the controller adjusts the opening of the phase separation valve to K4; wherein, K4>K3, T3<T4<T5;

[0035] Both K3 and K4 are related to the constant k, and the value of the constant k related to K3 is equal to the value of the constant k related to K4, and both are greater than the value of the constant k related to K1.

[0036] In one implementation, T1 is -15°C and T2 is -10°C.

[0037] In one implementation, T3 is -10°C, T4 is 0°C, and T5 is 10°C.

[0038] Compared with the prior art, the advantage of the present invention is that the controller adjusts the opening of the phase separation valve according to the number and diameter of the ablation needles connected in the connecting pipeline, so that the phase separation valve is kept at the target temperature, thereby achieving rapid cooling in a way that saves the most working fluid consumption under various combinations of ablation needles. Attached Figure Description

[0039] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.

[0040] Figure 1 This is a flowchart of the control method of the composite high and low temperature thermal ablation system in an embodiment of the present invention;

[0041] Figure 2 yes Figure 1 Flowchart for step 200;

[0042] Figure 3 yes Figure 1 Flowchart for step 403;

[0043] Figure 4 yes Figure 1 Flowchart for step 404;

[0044] Figure 5 yes Figure 1 Flowchart for step 405;

[0045] Figure 6 yes Figure 1 The flowchart for step 502. Detailed Implementation

[0046] The invention will now be further described with reference to the accompanying drawings.

[0047] This invention provides a composite high and low temperature cold and hot ablation system, including a working fluid storage tank, a phase separation valve, a connecting pipeline, an ablation needle, and a controller. The connecting pipeline is used to connect to the working fluid storage tank, the phase separation valve, and the ablation needle, and the controller is connected to the working fluid storage tank, the phase separation valve, and the ablation needle respectively.

[0048] The working fluid storage tank of the present invention can be, for example, a cold tank for storing cold working fluids such as liquid nitrogen. Its structure can adopt various implementation methods in the prior art. Similarly, the phase separation valve, connecting pipeline and ablation needle can also adopt various implementation methods in the prior art.

[0049] The controller of the present invention is configured to adjust the pressure of the working fluid storage tank according to the number of ablation needles connected in the connecting pipeline and the diameter of the ablation needles connected in the connecting pipeline.

[0050] The concept of this invention lies in designing different thresholds based on different combinations of ablation needle diameters and numbers, thereby achieving rapid cooling in the most efficient way (e.g., using liquid nitrogen) regardless of how the ablation needles are combined. Specifically, when the number of ablation needles connected in the pipeline is one, there are three cases.

[0051] The first scenario is: the number of ablation needles connected in the connecting tubing is 1, and the diameter of the ablation needle is ≥d1. Here, d1 can be, for example, 2.6mm. The fact that the diameter of the ablation needle connected in the connecting tubing is ≥d1 indicates that the diameter of the ablation needle connected in the connecting tubing may be 2.6mm or larger.

[0052] It should be noted that the diameter of the ablation needle refers to the diameter of the exit point at the tip of the ablation needle.

[0053] In the first case described above, the controller is configured to control the pressure boosting valve and / or venting valve on the working fluid storage tank, thereby adjusting the pressure of the working fluid storage tank to P1.

[0054] The controller regulates the pressure (working pressure) of the working fluid storage tank by controlling the opening and closing of the pressure boosting valve or the gradual opening and closing of the venting valve. The pressure boosting valve and venting valve can be electrically connected to the controller, which is configured to send commands to the valve to cause corresponding actions by relevant components, thereby adjusting the opening degree of the valve, such as fully opening (100%) or fully closing (0%).

[0055] For example, in the first case, the controller is configured such that when the pressure in the working fluid storage tank is less than P1-ΔP2, the controller fully opens the pressure boosting valve and fully closes the venting valve; when the pressure in the working fluid storage tank is between P1-ΔP2 and P1+ΔP2, the controller gradually closes the pressure boosting valve (at which point the venting valve is fully closed); when the pressure in the working fluid storage tank is greater than P1+ΔP2, the controller gradually opens the venting valve; when the pressure in the working fluid storage tank is less than P1-ΔP1, the controller fully closes the venting valve, thereby adjusting the pressure in the working fluid storage tank to P1; where ΔP1 < ΔP2.

[0056] More specifically, P1 can be, for example, 650 kPa, P2 can be, for example, 850 kPa, the value range of ΔP1 can be, for example, 5 kPa to 30 kPa, and the value range of ΔP2 can be, for example, 10 kPa to 50 kPa. The smaller the values ​​of ΔP1 and ΔP2, the higher the adjustment accuracy. Optionally, ΔP1 is 30 kPa and ΔP2 is 50 kPa; or alternatively, ΔP1 is 10 kPa and ΔP2 is 30 kPa; or alternatively, ΔP1 is 5 kPa and ΔP2 is 10 kPa. In the first case, the target pressure of the working fluid storage tank is 650 kPa. Under this target pressure, the temperature fed back by the phase separation valve can reach the target temperature within 10 minutes, which is much less than the preparation time before the ablation operation, thereby improving the efficiency of the ablation operation.

[0057] The following explanation uses ΔP1 as an example of 30 kPa and ΔP2 as an example of 50 kPa.

[0058] Understandably, in the first case, the target pressure is P1 (650 kPa), P1-ΔP2 is 600 kPa, P1+ΔP2 is 700 kPa, and P1-ΔP1 is 620 kPa.

[0059] When the pressure of the working medium storage tank is less than 600 kPa, the controller controls the pressure boosting valve to fully open and the venting valve to fully close, thus increasing the pressure of the working medium storage tank. When the pressure of the working medium storage tank is between 600 kPa and 700 kPa, the controller controls the pressure boosting valve to gradually close. When the pressure of the working medium storage tank is greater than 700 kPa, the controller controls the venting valve to gradually open, thus depressurizing the working medium storage tank to reduce its pressure. When the pressure of the working medium storage tank is less than 620 kPa, the controller controls the venting valve to fully close, thereby dynamically regulating the pressure of the working medium storage tank to 650 kPa.

[0060] During the above adjustment process, if the pressure in the working fluid storage tank is between 600 kPa and 700 kPa, it indicates that it is close to the target pressure. Therefore, the controller can gradually close the pressure boosting valve to gradually approach the target temperature. In other words, when adjusting the pressure of the working fluid storage tank, it is not directly compared with the target pressure, but rather compared with the lower limit (e.g., 600 kPa) and upper limit (e.g., 700 kPa) of the target pressure range. This ensures that the pressure in the working fluid storage tank gradually approaches the target temperature, taking into account the time required for both pressurization and depressurization, and avoids frequent opening / closing of the pressure boosting valve or venting valve, which could cause system turbulence.

[0061] The second scenario is: the number of ablation needles connected in the connecting tubing is 1, and the diameter of the ablation needle is between d2 and d1. Here, d2 can be, for example, 2mm, and the diameter of the ablation needle connected in the connecting tubing being between d2 and d1 indicates that the diameter of the ablation needle connected in the connecting tubing may be 2mm or 2.5mm, etc.

[0062] In the second case described above, the controller is configured to control the pressure boosting valve and / or venting valve on the working fluid storage tank, thereby adjusting the pressure of the working fluid storage tank to P2, where P1 < P2.

[0063] The controller regulates the pressure (working pressure) of the working medium storage tank by controlling the opening or closing of the pressure boosting valve on the working medium storage tank, or by controlling the gradual opening or closing of the venting valve on the working medium storage tank.

[0064] For example, in the second case, the controller is configured such that when the pressure in the working fluid storage tank is less than P2-ΔP2, the booster valve is fully opened and the vent valve is fully closed; when the pressure in the working fluid storage tank is between P2-ΔP2 and P2+ΔP2, the booster valve is gradually closed; when the pressure in the working fluid storage tank is greater than P2-ΔP2, the vent valve is gradually opened; and when the pressure in the working fluid storage tank is less than P2-ΔP1, the vent valve is fully closed, thereby adjusting the pressure in the working fluid storage tank to P2; where ΔP1 < ΔP2.

[0065] More specifically, d2 can be, for example, 2 mm, and P2 can be, for example, 850 kPa.

[0066] Understandably, in the second case, the target pressure is P2 (850 kPa), P2-ΔP2 is 800 kPa, P2+ΔP2 is 900 kPa, and P2-ΔP1 is 820 kPa.

[0067] In other words, in the second scenario, the target pressure of the working fluid storage tank is 850 kPa. When the pressure of the working fluid storage tank is less than 800 kPa, the controller fully opens the pressure boosting valve and fully closes the venting valve, allowing the working fluid storage tank to be pressurized to increase its pressure. When the pressure of the working fluid storage tank is between 800 kPa and 900 kPa, the controller gradually closes the pressure boosting valve. When the pressure of the working fluid storage tank is greater than 800 kPa, the controller gradually opens the venting valve, allowing the working fluid storage tank to be depressurized to reduce its pressure. When the pressure of the working fluid storage tank is less than 820 kPa, the controller fully closes the venting valve, thereby dynamically adjusting the pressure of the working fluid storage tank to 850 kPa.

[0068] During the above adjustment process, if the pressure in the working fluid storage tank is between 800 kPa and 900 kPa, it indicates that it is close to the target pressure. Therefore, the controller can gradually close the pressure boosting valve to gradually approach the target temperature. In other words, when adjusting the pressure of the working fluid storage tank, it is not directly compared with the target pressure, but rather compared with the lower limit (e.g., 800 kPa) and upper limit (e.g., 900 kPa) of the target pressure range. This ensures that the pressure in the working fluid storage tank gradually approaches the target temperature, taking into account the time required for both pressurization and depressurization, and avoids frequent opening / closing of the pressure boosting valve or venting valve, which could cause system turbulence.

[0069] The third scenario is: the number of ablation needles connected in the connecting tubing is 1, and the diameter of the ablation needle is < d2. Here, d2 can be, for example, 2 mm, and the diameter of the ablation needle connected in the connecting tubing < d2 indicates that the diameter of the ablation needle connected in the connecting tubing may be 1.7 mm.

[0070] In the third scenario described above, the controller adjusts the pressure of the working fluid storage tank to P3.

[0071] The controller regulates the pressure (working pressure) of the working medium storage tank by controlling the opening or closing of the pressure boosting valve on the working medium storage tank, or by controlling the gradual opening or closing of the venting valve on the working medium storage tank.

[0072] For example, in the third case, when the pressure of the working fluid storage tank is less than P3-2ΔP2, the pressure boosting valve is fully opened and the venting valve is fully closed; when the pressure of the working fluid storage tank is between P3-3ΔP2 and P3-ΔP2, the pressure boosting valve is gradually closed; when the pressure of the working fluid storage tank is greater than P3-ΔP2, the venting valve is gradually opened; when the pressure of the working fluid storage tank is less than P3-ΔP3, the venting valve is fully closed, thereby adjusting the pressure of the working fluid storage tank to P2; where P1 < P2 < P3; ΔP1 < ΔP2 < ΔP3.

[0073] More specifically, P3 can be, for example, 1000 kPa, and the range of ΔP3 can be, for example, 30 kPa to 80 kPa. Optionally, ΔP3 can be 80 kPa, ΔP3 can be 50 kPa, or ΔP3 can be 30 kPa.

[0074] In other words, in the third scenario, the target pressure of the working fluid storage tank is 1000 kPa. When the pressure of the working fluid storage tank is less than 900 kPa, the controller controls the pressure boosting valve to fully open and the venting valve to fully close, allowing the working fluid storage tank to be pressurized to increase its pressure. When the pressure of the working fluid storage tank is between 850 kPa and 950 kPa, the controller controls the pressure boosting valve to gradually close. When the pressure of the working fluid storage tank is greater than 950 kPa, the controller controls the venting valve to gradually open, allowing the working fluid storage tank to be depressurized to reduce its pressure. When the pressure of the working fluid storage tank is less than 920 kPa, the controller controls the venting valve to fully close, thereby dynamically adjusting the pressure of the working fluid storage tank to 1000 kPa.

[0075] During the above adjustment process, since the maximum pressure of the working fluid storage tank is set to 1000 kPa, the lower limit of the target pressure range can be 850 kPa, and the upper limit (which cannot exceed the maximum pressure) can be 950 kPa.

[0076] Similarly, if the pressure in the working fluid storage tank is between 850 kPa and 950 kPa, it indicates that it is already close to the target pressure. Therefore, the controller can gradually close the pressure boosting valve to gradually approach the target temperature. In other words, when adjusting the pressure in the working fluid storage tank, it is not directly compared with the target pressure, but rather with the lower limit (e.g., 850 kPa) and upper limit (e.g., 950 kPa) of the target pressure range. This ensures that the pressure in the working fluid storage tank gradually approaches the target temperature, taking into account the time required for both pressurization and depressurization, and avoids frequent opening / closing of the pressure boosting or venting valves, which could cause system turbulence.

[0077] Based on the first, second, and third scenarios above, when the number of ablation needles connected in the pipeline is the same, the smaller the diameter of the ablation needle, the higher the pressure of the working fluid storage tank needs to be adjusted to ensure that the temperature of the cold working fluid at the tip of each ablation needle of different diameters meets the treatment temperature requirements.

[0078] In addition, when the number of ablation needles connected in the connecting pipeline is greater than or equal to 2, it is divided into the following four and five cases.

[0079] The fourth scenario is when the number of ablation needles connected in the pipeline is ≥2 and the diameter of the ablation needles is ≥d2. In this fourth scenario, the controller is configured to control the pressure boosting valve and / or venting valve on the working fluid storage tank, thereby adjusting the pressure of the working fluid storage tank to P1.

[0080] In the fourth case, the controller can use the same control method as in the first case to adjust the pressure of the working fluid storage tank to P1, which will not be elaborated further in this invention.

[0081] The fifth scenario is as follows: when the number of ablation needles connected in the pipeline is ≥2 and the diameter of the ablation needle is <d2, the controller controls the pressure boosting valve and / or venting valve on the working fluid storage tank to adjust the pressure of the working fluid storage tank to P2; where P1 < P2.

[0082] In the fifth case, the controller can use the same control method as in the second case to adjust the pressure of the working fluid storage tank to P2, which will not be elaborated further in this invention.

[0083] Based on the fourth and fifth scenarios above, when the number of ablation needles connected in the pipeline is the same, the smaller the diameter of the ablation needle, the higher the pressure of the working fluid storage tank needs to be adjusted to ensure that the temperature of the cold working fluid at the tip of each ablation needle of different diameters meets the treatment temperature requirements.

[0084] In addition, for the case where the number of ablation needles connected in the connecting pipeline is 0, i.e., the sixth case, the controller control method is as follows.

[0085] The controller is designed so that when the number of ablation needles connected in the pipeline is 0, the controller controls the pressure boosting valve and / or venting valve on the working fluid storage tank, thereby adjusting the pressure in the working fluid storage tank from P3 to P1-ΔP2, i.e., the target pressure is P1-ΔP2. Since the number of ablation needles connected in the pipeline is 0, meaning no ablation needles are connected, it indicates that the process is in preparation before the ablation operation. Therefore, in this case, the pressure in the working fluid storage tank can be adjusted to a smaller pressure range to avoid wasting the working fluid (liquid nitrogen).

[0086] Specifically, when the pressure in the working fluid storage tank is less than P1-2ΔP2, the pressure boosting valve is fully opened and the venting valve is fully closed; when the pressure in the working fluid storage tank is between P1-2ΔP2 and P1, the pressure boosting valve is gradually closed (at this time, the venting valve is fully closed); when the pressure in the working fluid storage tank is greater than P1, the venting valve is gradually opened; when the pressure in the working fluid storage tank is less than P1-ΔP3, the venting valve is fully closed, thereby adjusting the pressure in the working fluid storage tank to P1-2ΔP2. Where ΔP1 < ΔP2 < ΔP3 < P1 < P3.

[0087] Understandably, in the sixth case, the target pressure is P1-ΔP2 (600 kPa), P1-2ΔP2 is 550 kPa, and P1-ΔP3 is 570 kPa.

[0088] More specifically, in the sixth case, since the ablation needle is not connected in the connecting pipeline, it indicates that no ablation operation is performed at this time, but a pre-cooling operation is performed. Therefore, in the pre-cooling operation, it is necessary to control the target pressure of the working fluid storage tank to a small level, so as to reduce the consumption of liquid nitrogen.

[0089] In other words, in the sixth scenario, the target pressure of the working fluid storage tank is 600 kPa. When the pressure of the working fluid storage tank is less than 550 kPa, the controller controls the pressure boosting valve to fully open and the venting valve to fully close, allowing the working fluid storage tank to be pressurized to increase its pressure. When the pressure of the working fluid storage tank is between 550 kPa and 650 kPa, the controller controls the pressure boosting valve to gradually close. When the pressure of the working fluid storage tank is greater than 650 kPa, the controller controls the venting valve to gradually open, allowing the working fluid storage tank to be depressurized to reduce its pressure. When the pressure of the working fluid storage tank is less than 570 kPa, the controller controls the venting valve to fully close, thereby dynamically adjusting the pressure of the working fluid storage tank to 600 kPa.

[0090] During the above adjustment process, if the pressure in the working fluid storage tank is between 550 kPa and 650 kPa, it indicates that it is close to the target pressure. Therefore, the controller can gradually close the pressure boosting valve to gradually approach the target temperature. In other words, when adjusting the pressure of the working fluid storage tank, it is not directly compared with the target pressure, but rather compared with the lower limit (e.g., 550 kPa) and upper limit (e.g., 650 kPa) of the target pressure range. This ensures that the pressure in the working fluid storage tank gradually approaches the target temperature, taking into account the time required for both pressurization and depressurization, and avoids frequent opening / closing of the pressure boosting valve or venting valve, which could cause system turbulence.

[0091] In all the above scenarios, the controller uses PID control to regulate the opening and closing of the pressure boosting valve and the venting valve, allowing the pressure in the working fluid storage tank to gradually approach the target temperature. For example, controlling the gradual closing of the pressure boosting valve or the gradual opening of the venting valve can be achieved by adjusting the opening degree of the pressure boosting valve or the venting valve using PID control. For instance, the pressure boosting valve opening can be adjusted from 100% to 80%, then to 10%, and finally to 0%; or the venting valve opening can be adjusted from 0% to 20%, then to 70%, and finally to 100%.

[0092] In all the above-described cases, the working fluid storage tank is equipped with a pressure detection device, such as a pressure sensor, to detect its pressure. The pressure detection device is electrically connected to the controller, allowing it to provide feedback on the working fluid storage tank's pressure. Based on this pressure feedback, the controller implements the corresponding control strategies described above.

[0093] In a second aspect, the present invention provides a composite high and low temperature thermal ablation system, comprising a working fluid storage tank, a phase separation valve, a connecting pipeline, an ablation needle, and a controller. The connecting pipeline is used to connect to the working fluid storage tank, the phase separation valve, and the ablation needle, and the controller is connected to the working fluid storage tank, the phase separation valve, and the ablation needle respectively.

[0094] The working fluid storage tank of the present invention can be, for example, a cold tank for storing cold working fluids such as liquid nitrogen. Its structure can adopt various implementation methods in the prior art. Similarly, the phase separation valve, connecting pipeline and ablation needle can also adopt various implementation methods in the prior art.

[0095] The controller of this invention is configured to adjust the opening degree of the phase separation valve according to the number of ablation needles connected in the connecting pipeline and the diameter of the ablation needles connected in the connecting pipeline, so that the phase separation valve is maintained at a target temperature. The phase separation valve may, for example, be electrically connected to the controller, which is configured to send relevant commands to the phase separation valve to cause relevant components on the phase separation valve to perform corresponding actions, thereby adjusting the opening degree of the phase separation valve, for example, setting the opening degree of the phase separation valve to 100% or 0%.

[0096] The concept of this invention is to design different thresholds based on different combinations of ablation needle diameters and numbers, so as to achieve rapid cooling in the most liquid nitrogen-saving way regardless of how the ablation needles are combined.

[0097] Specifically, when the number of ablation needles connected in the connecting pipeline is 1, there are three situations.

[0098] The first scenario is: the number of ablation needles connected in the connecting pipeline is 1 and the diameter of the ablation needle is ≥d1, where d1 can be, for example, 2.6mm. The fact that the diameter of the ablation needle connected in the connecting pipeline is ≥d1 indicates that the diameter of the ablation needle connected in the connecting pipeline may be 2.6mm or larger.

[0099] In the first case described above, the controller is configured such that the opening of the phase separation valve is maintained at the target temperature T3 to T4.

[0100] Specifically, when the current temperature of the phase separation valve is ≥ T5, the controller adjusts the opening of the phase separation valve to 100%; when T4 ≤ the current temperature of the phase separation valve < T5, the controller adjusts the opening of the phase separation valve to K3; when T3 ≤ the current temperature of the phase separation valve < T4, the controller adjusts the opening of the phase separation valve to K4, where K4 > K3; when the current temperature of the phase separation valve is ≤ T3, the controller adjusts the opening of the phase separation valve to 0%, where T3 < T4 < T5.

[0101] K3 and K4 satisfy the following expressions respectively:

[0102]

[0103] Where k is a constant, and its value ranges from 1 to k to 1.2.

[0104] The value of k is an empirical constant summarized and verified based on experimental results, and its value is related to the pressure of the working fluid storage tank and the number of ablation needles connected in the pipeline. In the first case, the pressure of the working fluid storage tank is the target pressure P1 (650 kPa), and the number of ablation needles connected in the pipeline is 1. Therefore, the controller adjustment needs to be more significant so that the phase separation valve can be adjusted to the target temperature more quickly, thus bringing the value of k closer to its maximum value. Therefore, in the first case, the value of k can be 1.15.

[0105] More specifically, T3 is -5℃, T4 is 0℃, and T5 is 10℃. Understandably, in the first case described above, the controller is configured such that the opening of the phase separation valve is maintained at the target temperature of -5℃ to 0℃.

[0106] Specifically, when T3 is -5℃, the flow rate of the phase separation valve is 15L / min-18L / min; when T4 is 0℃, the flow rate of the phase separation valve is 10L / min-14L / min; and when T5 is 10℃, the flow rate of the phase separation valve is 8L / min-10L / min, which ensures that the consumption of liquid nitrogen is relatively low.

[0107] Therefore, the controller adjusts the opening degree of the phase separation valve as follows:

[0108] When the current temperature of the phase separation valve is ≥10℃, the controller adjusts the opening of the phase separation valve to 100%; when 0℃≤current temperature of the phase separation valve<10℃, the controller adjusts the opening of the phase separation valve to K3; when -5℃≤current temperature of the phase separation valve<0℃, the controller adjusts the opening of the phase separation valve to K4, where K4>K3; when the current temperature of the phase separation valve is ≤-5℃, the controller adjusts the opening of the phase separation valve to 0%.

[0109] K3 satisfies the following expression:

[0110]

[0111] K4 satisfies the following expressions:

[0112]

[0113] The second scenario is: the number of ablation needles connected in the connecting tubing is 1, and the diameter of the ablation needle is between d2 and d1. Here, d2 can be, for example, 2mm, and the diameter of the ablation needle connected in the connecting tubing being between d2 and d1 indicates that the diameter of the ablation needle connected in the connecting tubing may be 2mm or 2.5mm, etc.

[0114] In the second scenario described above, the controller adjusts the opening of the phase separation valve to maintain it at a target temperature, which is T3 to T4. Understandably, in this second scenario, the controller is configured to adjust the opening of the phase separation valve to maintain it at a target temperature of -5°C to 0°C.

[0115] In the second case, the controller can use the same control method as in the first case to adjust the opening of the phase separation valve to keep the phase separation valve at the target temperature, which is T3 to T4. This invention will not elaborate further on this.

[0116] The third scenario is: the number of ablation needles connected in the connecting tubing is 1, and the diameter of the ablation needle is < d2. Here, d2 can be, for example, 2 mm, and the diameter of the ablation needle connected in the connecting tubing < d2 indicates that the diameter of the ablation needle connected in the connecting tubing may be 1.7 mm.

[0117] In the third case, the controller is configured to adjust the opening of the phase separation valve to maintain the phase separation valve at a target temperature, which is T1 to T2.

[0118] Specifically, when the current temperature of the phase separation valve is ≥ T2, the controller adjusts the opening of the phase separation valve to 100%; when T1 ≤ the current temperature of the phase separation valve < T2, the controller adjusts the opening of the phase separation valve to K1; when the current temperature of the phase separation valve < T1, the controller adjusts the opening of the phase separation valve to 0%, where T1 < T2; and K1 satisfies the following expression:

[0119]

[0120] k is a constant, and its value range is 1≤k≤1.2.

[0121] The value of k is an empirical constant summarized and verified based on experimental results, and its value is related to the pressure of the working fluid storage tank and the number of ablation needles connected in the connecting pipeline. In the third case, the pressure of the working fluid storage tank is the target pressure P3 (1000 kPa), and the number of ablation needles connected in the connecting pipeline is 1. Therefore, the degree of controller adjustment can be slightly smaller than in the first case. Thus, in the third case, the value of k can be 1.12.

[0122] More specifically, T1 can be, for example, -15°C, and T2 can be, for example, -10°C. Understandably, in the third case described above, the controller is configured such that the opening of the phase separation valve is maintained at the target temperature of -15°C to -10°C.

[0123] Therefore, the controller adjusts the opening degree of the phase separation valve as follows:

[0124] When the current temperature of the phase separation valve is ≥ -10℃, the controller adjusts the opening of the phase separation valve to 100%; when -15℃ ≤ the current temperature of the phase separation valve < -10℃, the controller adjusts the opening of the phase separation valve to K1; when the current temperature of the phase separation valve is < -15℃, the controller adjusts the opening of the phase separation valve to 0%, where T1 < T2; and K1 satisfies the following expression:

[0125]

[0126] In addition, when the number of ablation needles connected in the connecting pipeline is greater than or equal to 2, it is divided into the following four and five cases.

[0127] The fourth scenario is when the number of ablation needles connected in the pipeline is ≥2 and the diameter of the ablation needles is ≥d2. In this fourth scenario, the controller adjusts the opening of the phase separation valve to maintain the phase separation valve at a target temperature, which is T3 to T4. Understandably, in the second scenario, the controller is configured to adjust the opening of the phase separation valve to maintain it at a target temperature of -5℃ to 0℃.

[0128] In the fourth case, the controller can use the same control method as in the first case to adjust the opening of the phase separation valve to keep the phase separation valve at the target temperature, which is T3 to T4. This invention will not elaborate further on this.

[0129] Furthermore, the fifth case is: when the number of ablation needles connected in the connecting pipeline is ≥2 and the diameter of the ablation needle is <d2.

[0130] In the fifth scenario, the controller adjusts the opening of the phase separation valve to maintain it at a target temperature, which is T2 to T3. Understandably, in this fifth scenario, the controller is configured to adjust the opening of the phase separation valve to maintain it at a target temperature of -10°C to -5°C.

[0131] For example, in the fifth case, when the current temperature of the phase separation valve is ≥ T3, the controller adjusts the opening of the phase separation valve to 100%; when T2 ≤ the current temperature of the phase separation valve < T3, the controller adjusts the opening of the phase separation valve to K2; when the current temperature of the phase separation valve < T2, the controller adjusts the opening of the phase separation valve to 0%, where T2 < T3; and K2 satisfies the following expression:

[0132]

[0133] k is a constant, and its value range is 1≤k≤1.2.

[0134] The value of k is an empirical constant summarized and verified based on experimental results, and its value is related to the pressure of the working fluid storage tank and the number of ablation needles connected in the connecting pipeline. In the fifth case, the pressure of the working fluid storage tank is the target pressure P2 (850 kPa), and the number of ablation needles connected in the connecting pipeline is 2. Therefore, the degree of controller adjustment can be smaller than in the first case. Thus, in the fifth case, the value of k can be 1.05.

[0135] Therefore, the controller adjusts the opening degree of the phase separation valve as follows:

[0136] When the current temperature of the phase separation valve is ≥ -5℃, the controller adjusts the opening of the phase separation valve to 100%; when -10℃ ≤ the current temperature of the phase separation valve < -5℃, the controller adjusts the opening of the phase separation valve to K2; when the current temperature of the phase separation valve is < -10℃, the controller adjusts the opening of the phase separation valve to 0%, where K2 satisfies the following expression:

[0137]

[0138] Furthermore, in the case where the number of ablation needles connected in the connecting pipeline is 0, i.e., the sixth case, the controller is configured such that when the number of ablation needles connected in the connecting pipeline is 0, the controller adjusts the opening of the phase separation valve to maintain the phase separation valve at the target temperature, which is T3 to T4.

[0139] In the sixth scenario, the controller can employ the same control method as in the first scenario to adjust the opening of the phase separation valve to maintain it at the target temperature, which is T3 to T4. This will not be elaborated further in this invention. Understandably, in the sixth scenario, the controller is configured to adjust the opening of the phase separation valve to maintain it at the target temperature of -5°C to 0°C.

[0140] It should be noted that the current temperature of the phase separation valve refers to the temperature obtained at the temperature measuring point downstream of the phase separation valve, which is generally the temperature of the gaseous working fluid separated by the phase separation valve (or may also include a small amount of liquid working fluid). Therefore, if the current temperature of the phase separation valve is high (e.g., greater than 10°C), it indicates that there is a large amount of gas in the working fluid, so it is necessary to increase the opening of the phase separation valve to increase the discharge gas velocity.

[0141] In all the above scenarios, the value of k is related to the pressure of the working fluid storage tank and the number of ablation needles connected in the connecting pipeline. Specifically, the lower the pressure of the working fluid storage tank, the larger the value of k; and the fewer the number of ablation needles connected in the connecting pipeline, the larger the value of k. A larger value of k indicates a greater degree of adjustment of the phase separation valve opening by the controller, thus enabling more agile feedback adjustment based on the phase separation temperature.

[0142] In all the above-described cases, a temperature detection device, such as a temperature sensor or thermocouple, is installed on the phase separation valve (or in its downstream pipeline) to detect the temperature of the phase separation valve. The temperature detection device is electrically connected to the controller, allowing it to provide feedback on the temperature of the working fluid storage tank. Based on the temperature feedback from the temperature detection device, the controller implements the corresponding control strategy described above.

[0143] Furthermore, the controller of the present invention can also be configured to adjust the pressure of the working fluid storage tank and the opening of the phase separation valve according to the number of ablation needles connected in the connecting pipeline and the diameter of the ablation needles connected in the connecting pipeline, so that the pressure of the working fluid storage tank is maintained near the target pressure and the phase separation valve is maintained at the target temperature.

[0144] In a third aspect, the present invention provides a control method for a composite high-low temperature thermal ablation system. The control method is applied to the aforementioned composite high-low temperature thermal ablation system and includes the following steps:

[0145] Step 100: Determine if the number of ablation needles connected in the connecting pipeline is 0. If yes, proceed to step 200; otherwise, proceed to step 300.

[0146] Specifically, feedback can be provided through the connection positioning device on the ablation needle. For example, when the connecting tube is connected to the corresponding ablation needle, it indicates that the two are properly engaged, and the connection positioning device will send a signal to the controller that the ablation needle is connected, indicating that the ablation needle is connected in the connecting tube; otherwise, it indicates that the ablation needle is not connected in the connecting tube.

[0147] Step 200: For the case where the number of ablation needles connected in the connecting pipeline is 0 (i.e., the sixth case mentioned above), adjust the pressure of the working fluid storage tank from P3 to P1-ΔP2, and maintain the current temperature of the phase separation valve between T3 and T4.

[0148] In this case, adjusting the pressure of the working fluid storage tank from P3 to P1-ΔP2 and maintaining the current temperature of the phase separation valve between T3 and T4 can be achieved using the control method described in the sixth case above.

[0149] Step 300: If the number of ablation needles connected in the connecting tubing is not zero, further judgment is required. Specifically, determine whether the number of ablation needles connected in the connecting tubing is 1. If yes, proceed to step 400; otherwise, proceed to step 500.

[0150] Step 400: If the number of ablation needles connected in the connecting pipeline is 1, further judgment is required. That is, determine whether the diameter of the ablation needle connected in the connecting pipeline is ≥d1. If the diameter of the ablation needle connected in the connecting pipeline is ≥d1 (i.e., corresponding to the first case above), then adjust the pressure of the working fluid storage tank to P1 and maintain the current temperature of the phase separation valve between T3 and T4 (i.e., step 403); otherwise, proceed to step 401, that is, further judgment is required.

[0151] In this case, adjusting the pressure of the working fluid storage tank to P1 and maintaining the current temperature of the phase separation valve between T3 and T4 can be achieved using the control method described in the first case above.

[0152] Step 401: Determine whether the diameter of the ablation needle connected in the connecting pipeline is between d2 and d1. If the diameter of the ablation needle connected in the connecting pipeline is between d2 and d1 (i.e., corresponding to the second case above), then adjust the pressure of the working fluid storage tank to P2 and maintain the current temperature of the phase separation valve between T3 and T4 (i.e., step 404); otherwise, proceed to step 402.

[0153] In this case, adjusting the pressure of the working fluid storage tank to P2 and maintaining the current temperature of the phase separation valve between T3 and T4 can be achieved using the control method described in the second scenario above.

[0154] Step 402: Determine if the diameter of the ablation needle connected in the connecting pipeline is less than d2. If the diameter of the ablation needle connected in the connecting pipeline is less than d2 (i.e., corresponding to the third case described above), then adjust the pressure of the working fluid storage tank to P3 and maintain the current temperature of the phase separation valve between T1 and T2.

[0155] In this case, adjusting the pressure of the working fluid storage tank to P3 and maintaining the current temperature of the phase separation valve between T1 and T2 (i.e., step 405) can be achieved using the control method described in the third case above.

[0156] 500: If the number of ablation needles connected in the connecting pipeline is ≥2, further judgment is required. That is, determine whether the diameter of the ablation needles connected in the connecting pipeline is ≥d2. If the diameter of the ablation needles connected in the connecting pipeline is ≥d2 (i.e., the fourth case mentioned above), then adjust the pressure of the working fluid storage tank to P1 and maintain the current temperature of the phase separation valve between T3 and T4 (i.e., step 403); otherwise, proceed to step 501.

[0157] In this case, adjusting the pressure of the working fluid storage tank to P1 and maintaining the current temperature of the phase separation valve between T3 and T4 can be achieved using the control method described in the fourth case above.

[0158] 501: Determine if the diameter of the ablation needle connected in the connecting pipeline is less than d2. If the diameter of the ablation needle connected in the connecting pipeline is less than d2 (i.e., corresponding to the fifth case described above), then adjust the pressure of the working fluid storage tank to P2 and maintain the current temperature of the phase separation valve between T2 and T3 (i.e., step 502). Wherein, ΔP2 < P1 < P2 < P3; T1 < T2 < T3 < T4.

[0159] In this case, adjusting the pressure of the working fluid storage tank to P2 and maintaining the current temperature of the phase separation valve between T2 and T3 can be achieved using the control method described in the fifth case above.

[0160] This method can be terminated once the pre-cooling or ablation operation is completed.

[0161] Example 1

[0162] The ablation needle is not connected in the pipeline.

[0163] The target pressure of the working fluid storage tank is 600 kPa. When the pressure of the working fluid storage tank is less than 550 kPa, the controller controls the pressure boosting valve to fully open and the venting valve to fully close. When the pressure of the working fluid storage tank is between 550 kPa and 650 kPa, the controller controls the pressure boosting valve to gradually close. When the pressure of the working fluid storage tank is greater than 650 kPa, the controller controls the venting valve to gradually open. When the pressure of the working fluid storage tank is less than 650 kPa, the controller controls the venting valve to fully close, thereby dynamically adjusting the pressure of the working fluid storage tank to 570 kPa.

[0164] During this process, the liquid nitrogen consumption is approximately 3%, and the pre-cooling operation of the composite high-low temperature thermal ablation system lasts for 6 minutes (i.e., the time it takes for the composite high-low temperature thermal ablation system to cool down to the required temperature).

[0165] Therefore, when the ablation needle is not connected in the connecting pipeline, that is, during the precooling process of the system, the pressure of the working fluid storage tank is controlled so that the consumption of liquid nitrogen meets the requirement of less than 8%, and the precooling time meets the requirement of no more than 8 minutes.

[0166] Example 2

[0167] The number of ablation needles connected in the connecting pipeline is 1.

[0168] The ablation needle has a diameter of 3mm. The target pressure of the working fluid storage tank is 650kPa. When the pressure of the working fluid storage tank is less than 600kPa, the controller controls the pressure boosting valve to fully open and the venting valve to fully close. When the pressure of the working fluid storage tank is between 600kPa and 700kPa, the controller controls the pressure boosting valve to gradually close. When the pressure of the working fluid storage tank is greater than 700kPa, the controller controls the venting valve to gradually open. When the pressure of the working fluid storage tank is less than 620Pa, the controller controls the venting valve to fully close, thereby dynamically adjusting the pressure of the working fluid storage tank to 650kPa.

[0169] When using this ablation needle for ablation, the liquid nitrogen consumption is approximately 13%, the ice ball size is approximately 50mm (minor axis) × 70mm (major axis), and the ablation operation lasts for 20 minutes. It should be noted that the above ice ball dimensions are measured in a gelatin environment at 37°C.

[0170] The ablation needle has a diameter of 2.6 mm. The target pressure of the working fluid storage tank is 850 kPa. When the pressure of the working fluid storage tank is less than 800 kPa, the controller controls the pressure boosting valve to fully open and the venting valve to fully close. When the pressure of the working fluid storage tank is between 800 kPa and 900 kPa, the controller controls the pressure boosting valve to gradually close. When the pressure of the working fluid storage tank is greater than 800 kPa, the controller controls the venting valve to gradually open. When the pressure of the working fluid storage tank is less than 820 kPa, the controller controls the venting valve to fully close, thereby dynamically adjusting the pressure of the working fluid storage tank to 850 kPa.

[0171] When using this ablation needle for ablation, the liquid nitrogen consumption is approximately 15%, the ice ball size is approximately 43mm (minor axis) × 52mm (major axis), and the ablation operation lasts for 20 minutes. It should be noted that the above ice ball dimensions are measured in a gelatin environment at 37°C.

[0172] The ablation needle has a diameter of 1.7 mm. The target pressure of the working fluid storage tank is 1000 kPa. When the pressure of the working fluid storage tank is less than 900 kPa, the controller controls the pressure boosting valve to fully open and the venting valve to fully close. When the pressure of the working fluid storage tank is between 850 kPa and 950 kPa, the controller controls the pressure boosting valve to gradually close. When the pressure of the working fluid storage tank is greater than 950 kPa, the controller controls the venting valve to gradually open. When the pressure of the working fluid storage tank is less than 920 kPa, the controller controls the venting valve to fully close, thereby dynamically adjusting the pressure of the working fluid storage tank to 1000 kPa.

[0173] When using this ablation needle for ablation, the liquid nitrogen consumption is approximately 17%, the ice ball size is approximately 28mm (minor axis) × 32mm (major axis), and the ablation operation lasts for 20 minutes. It should be noted that the above ice ball dimensions are measured in a gelatin environment at 37°C. Therefore, when connecting the ablation needle in the tubing, the pressure of the working fluid storage tank should be controlled to ensure that the liquid nitrogen consumption (total) is less than 20% (for the minimum diameter of the ablation needle connected in the tubing).

[0174] Example 3

[0175] The number of ablation needles connected in the connecting pipeline is 2.

[0176] The ablation needles have diameters of 3mm and 2.6mm. The target pressure of the working fluid storage tank is 650kPa. When the pressure of the working fluid storage tank is less than 600kPa, the controller controls the pressure boosting valve to fully open and the venting valve to fully close; when the pressure of the working fluid storage tank is between 600kPa and 700kPa, the controller controls the pressure boosting valve to gradually close; when the pressure of the working fluid storage tank is greater than 700kPa, the controller controls the venting valve to gradually open; when the pressure of the working fluid storage tank is less than 620Pa, the controller controls the venting valve to fully close, thereby dynamically regulating the pressure of the working fluid storage tank to 650kPa.

[0177] When using this ablation needle for ablation, the liquid nitrogen consumption is approximately 28%, and the ablation operation lasts for 20 minutes.

[0178] The ablation needles have diameters of 1.7 mm and 1.7 mm. The target pressure of the working fluid storage tank is 850 kPa. When the pressure of the working fluid storage tank is less than 800 kPa, the controller controls the pressure boosting valve to fully open and the venting valve to fully close; when the pressure of the working fluid storage tank is between 800 kPa and 900 kPa, the controller controls the pressure boosting valve to gradually close; when the pressure of the working fluid storage tank is greater than 800 kPa, the controller controls the venting valve to gradually open; when the pressure of the working fluid storage tank is less than 820 kPa, the controller controls the venting valve to fully close, thereby dynamically adjusting the pressure of the working fluid storage tank to 850 kPa.

[0179] When using this ablation needle for ablation, the liquid nitrogen consumption is approximately 32%, the ice ball size is approximately 30mm (minor axis 1) × 37mm (minor axis 2) × 46mm (major axis) (the distance between the two ablation needles is 10mm), and the ablation operation lasts for 20 minutes. It should be noted that the above ice ball dimensions are measured in a gelatin environment at 37°C.

[0180] Therefore, when connecting the ablation needle in the connecting pipeline, the pressure of the working fluid storage tank is controlled so that the consumption (total) of liquid nitrogen basically meets the requirement of less than 30% (for the minimum diameter of the ablation needle connected in the connecting pipeline).

[0181] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A combined high and low temperature cold thermal ablation system, characterized by, The system comprises a working medium storage tank, a phase separation valve, a connecting pipeline, an ablation needle and a controller, the connecting pipeline is used for connecting the working medium storage tank, the phase separation valve and the ablation needle, and the controller is connected with the working medium storage tank, the phase separation valve and the ablation needle respectively; The controller is configured to adjust the opening degree of the phase separation valve according to the number of the ablation needles connected in the connecting pipeline and the diameter of the ablation needles connected in the connecting pipeline, so that the phase separation valve is kept at a target temperature. When the number of the ablation needles connected in the connecting pipeline is 1 and the diameter of the ablation needle is < 0.5 mm d 2, if T 1 < the current temperature of the phase separation valve < 2, the controller adjusts the opening degree of the phase separation valve to T 1; and K 2, the controller adjusts the opening degree of the phase separation valve to 2. when the number of the ablation needles connected in the connecting pipeline is ≥ 2 and the diameter of the ablation needles is < 0.5mm d 2, if T 2≤ the current temperature of the phase separation valve < 80℃ T 3, the controller adjusts the opening degree of the phase separation valve to K 2; wherein, T 1 < the current temperature of the phase separation valve < 80℃ T 2 < the current temperature of the phase separation valve < 80℃ T 3, K 1 and K 2 are related to a constant k and the constant K 1 is related to a constant k having a value greater than the constant K 2 is related to a constant k having a value; K 1 satisfies the following expression: k is constant and has a value in the range 1 < a < 1.2 k ≤1.2; K 2 satisfies the following expression: k is a constant, which has a value range of 1≤ k ≤1.

2.

2. The combined cryo- and thermal-ablation system of claim 1, wherein, The controller is configured to adjust an opening degree of the phase separation valve to maintain the phase separation valve at a target temperature when the number of the ablation needles communicated in the connection pipeline is 1 and the diameter of the ablation needle is < 0.4 mm. d 2; and the target temperature of the phase separation valve is 1 to 2. T 1. T 2. wherein, when the current temperature of the phase separation valve ≥ T 2, the controller adjusts the opening degree of the phase separation valve to 100%; when T 1 ≤ Current temperature of the phase separation valve < T At time 2, the controller adjusts the opening of the phase separation valve to... K 1; when the current temperature of the phase separation valve < 0°C, the controller adjusts the opening degree of the phase separation valve to 0%, wherein, T 1 T 1 < 0°C < 2°C, T 2°C. wherein 0% < x < 100% K 1 < 100%.

3. The combined high and low temperature cold thermal ablation system of claim 1 or 2, wherein, When the number of ablation needles connected in the connecting pipeline is ≥ 2 and the diameter of the ablation needle is < 2 d 2, the controller adjusts the opening degree of the phase separation valve to keep the phase separation valve at a target temperature, and the target temperature of the phase separation valve is 2 to T 3. T ​ wherein, when the current temperature of the phase separation valve ≥ T 3, the controller adjusts the opening degree of the phase separation valve to 100%. When T 2 < the current temperature of the phase separation valve < 3 T 3, the controller adjusts the opening of the phase separation valve to K 2. when the current temperature of the phase separation valve < 0°C, the controller adjusts the opening of the phase separation valve to 0%, wherein, T 2 is greater than 0°C, the controller adjusts the opening of the phase separation valve to 100%. T 2 is greater than 0°C, the controller adjusts the opening of the phase separation valve to 100%. T 3; wherein 0% < x < 100% K 2 < 100%.

4. The combined cryo- and thermal-ablation system of claim 1 or 2, wherein, The controller is configured to adjust the opening degree of the phase separation valve to maintain the phase separation valve at a target temperature when the number of ablation needles in communication in the connection line is 0 or when the number of ablation needles in communication in the connection line is ≥1 and the diameter of the ablation needles is ≥ d 2, the target temperature of the phase separation valve being T 3 to T 4. wherein, when the current temperature of the phase separation valve ≥ 5 T 5, the controller adjusts the opening degree of the phase separation valve to 100%. when T 4 ≤ Current temperature of the phase separation valve < T At time 5, the controller adjusts the opening of the phase separation valve to... K 3, When T 3 < the current temperature of the phase separation valve < 4 T 4, the controller adjusts the opening of the phase separation valve to K 4, wherein, K 4 > K 3; when the current temperature of the phase separation valve ≤ T 3, the controller adjusts the opening of the phase separation valve to 0%, wherein, T 3 < the current temperature of the phase separation valve < 4, T 4 < the current temperature of the phase separation valve < 5, T 5.

5. The combined high and low temperature cold thermal ablation system of claim 4, wherein, K 3 and K 4 satisfy the following expressions, respectively: wherein k is a constant having a value in the range 1≤ k ≤1.

2.

6. The combined cryo- and hyperthermia ablation system of claim 1, wherein, When the number of ablation needles connected in the connecting pipeline is 0, or when the number of ablation needles connected in the connecting pipeline is ≥1 and the diameter of the ablation needle is ≥ d At 2 o'clock, if T 4 ≤ Current temperature of the phase separation valve < T 5. The controller adjusts the opening degree of the phase separation valve to... K 3; if T 3 ≤ Current temperature of the phase separation valve < T 4. The controller adjusts the opening degree of the phase separation valve to... K 4; wherein K 4 K 3 T 3 T 4 T 5 K 3 and K 4 are related to a constant k and the constant K 3 is related to a constant k having a value equal to the constant K 4 is related to a constant k having a value equal to the constant K 1 is related to a constant k having a value less than the constant 7. The combined cryo- and hyperthermia ablation system of claim 2, wherein, T 1 is -15°C, T 2 is -10°C.

8. The combined high and low temperature cold thermal ablation system of claim 4, wherein, T 3 is -10°C, T 4 is 0°C, T 5 is 10°C.

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