JP5804414B2 - Cryosurgical apparatus and temperature control method thereof - Google Patents

Description

  The present invention relates to a cryosurgical apparatus and a temperature control method thereof, and more particularly, to a cryosurgical apparatus suitable for treatment of a minute region such as a skin spot or wrinkle, early breast cancer, or around the right atrial sinoatrial node, and a temperature control method thereof. .

  At present, cryosurgery is performed in which the affected part that has fallen into a tumor or dysfunction is not excised, and the affected part is cooled to a low temperature of about −20 ° C. using a cryosurgical probe called cryoprobe and frozen to cause necrosis. . The cryosurgery is capable of performing local treatment only on the affected area, and has various advantages such as less bleeding, inflammatory reaction, and pain, and a short period of time for recovery.

  The cryosurgical device can be cooled by using a phase change that cools by flowing liquid nitrogen through the cryoprobe and evaporating at the tip, or by Joule-Thompson cooling using a high-pressure gas such as argon gas or carbon dioxide There is use of enthalpy expansion such as The general size of the cryoprobe has an outer diameter of about 2 mm to 8 mm.

  However, with such a device, it is difficult to locally treat a region smaller than the outer diameter of a general cryoprobe, such as spots and wrinkles present on the face, early breast cancer, and around the sinoatrial node of the right atrium. In addition, when the affected part in the body is frozen using an endoscope, a catheter, or the like, there is a problem that it is necessary to insulate a pipe that is extremely cold until reaching the affected part. In addition, there is a problem that a large reservoir or cylinder is required to flow the refrigerant at a large flow rate to ensure a high cooling capacity and to discharge it into the atmosphere.

  On the other hand, as a cryosurgical device intended to be used in the body, Japanese Patent Application Laid-Open No. 2006-130024 discloses that a Peltier element can be used to facilitate temperature control with a probe and to send a refrigerant to the probe. It is described that this flexible tube has a multiple tube structure, and a liquid refrigerant is allowed to flow through the outer tube at room temperature, thereby eliminating the need for heat insulation of the tube. However, the refrigerant from the probe is released to the atmosphere, and the above problem has not been solved.

Japanese Patent Laid-Open No. 2006-130024

  Therefore, in view of the above problems, the present invention can reduce the cooling surface of the probe to a very small area, thus enabling cryotherapy of a minute region, and it is necessary to insulate the pipe that supplies the refrigerant to the affected area. It is an object of the present invention to provide a cryosurgical apparatus and a temperature control method thereof that can reuse the refrigerant without releasing the refrigerant into the atmosphere.

  In order to achieve the above object, a cryosurgical apparatus according to the present invention comprises a probe for freezing an affected part, a container for holding a refrigerant used in the probe in a liquid state under a pressurized condition, and the gas state A condenser that cools and condenses the refrigerant; a first pipe that sends the liquid refrigerant from the container to the probe; and a second pipe that sends the gaseous refrigerant from the probe to the condenser. And the probe has a double tube structure including an inner tube and an outer tube, and the inner tube depressurizes the liquid refrigerant from the first tube, and the outer tube. The outer surface of the affected part comes into contact with the affected part, and the decompressed refrigerant flows into the affected part, and the heat from the affected part is removed to vaporize the refrigerant.

  The inner tube of the probe preferably has an outer diameter of 50 to 200 μm and a wall thickness of 10 to 40 μm, and the outer tube of the probe preferably has an outer diameter of 200 to 700 μm and a wall thickness of 10 to 180 μm. The cryosurgical apparatus according to the present invention further includes a bypass pipe that connects the first pipe and the second pipe without using the probe, and the bypass pipe includes a valve that can be opened and closed. preferable.

  A temperature control method for a cryosurgical apparatus according to the present invention includes a probe for freezing an affected part, a container for holding a refrigerant used in the probe in a liquid state under a pressurized condition, and cooling the refrigerant in a gaseous state. In a cryosurgical apparatus comprising: a condenser that condenses; a first pipe that sends the liquid refrigerant from the container to the probe; and a second pipe that sends the gaseous refrigerant from the probe to the condenser. And the step of cooling the probe by communicating the liquid state refrigerant to the probe and evaporating the refrigerant by communicating the container with the condenser via the first and second tubes and the probe. And stopping the cooling of the probe by disabling the container and the probe and communicating the first tube with the condenser without the probe. It is intended to include.

  It is preferable that the temperature control method of the cryosurgical apparatus further includes a step of heating the refrigerant condensed in the condenser to return it to the liquid state refrigerant under the original pressurized condition.

  As described above, according to the present invention, the probe has a double tube structure, the refrigerant in the liquid state is decompressed by the inner tube, and the outer surface of the outer tube is brought into contact with the affected part. By flowing the decompressed refrigerant and removing the heat from the affected area to evaporate the refrigerant, the cooling surface of the probe can be made into a minute area, and thus cryosurgery of a minute lesion can be performed. . In addition, since the cooling surface is minute, the vaporized refrigerant easily rises to the ambient temperature such as the affected part, and thus it is not necessary to insulate the pipe that sends the refrigerant. Furthermore, since the flow rate of the refrigerant flowing in the probe is reduced, a condenser capable of cooling and condensing the gaseous refrigerant can be provided. By providing a condenser by cooling, a negative pressure is formed, and even with a probe having such a small cooling surface, the refrigerant can be easily flowed, and the refrigerant is reused without releasing the refrigerant to the atmosphere. be able to.

  For example, the inner tube of the probe preferably has an outer diameter of 50 to 200 μm and a wall thickness of 10 to 40 μm, and the outer tube of the probe preferably has an outer diameter of 200 to 700 μm and a wall thickness of 10 to 180 μm. Thus, by making the flow path of the refrigerant in the probe very small, the pressure loss increases and the flow rate of the refrigerant can be kept low. Thereby, it is possible to prevent the flow rate of the refrigerant in the gas state flowing from the probe into the condenser from exceeding the speed (flow rate) of the refrigerant that changes in phase from gas to liquid by cooling in the condenser. The cooling performance can be maintained.

It is a mimetic diagram showing one embodiment of a cryosurgery device concerning the present invention. It is an expanded sectional view which shows the probe of the cryosurgery apparatus shown in FIG. It is sectional drawing which shows another form of the probe of the cryosurgery apparatus which concerns on this invention. It is a schematic diagram which shows the structure of the cryosurgery apparatus used in the Example. It is a graph which shows the temperature change of the probe in an Example.

  Hereinafter, an embodiment of a cryosurgical apparatus and a temperature control method thereof according to the present invention will be described with reference to the accompanying drawings. As shown in FIG. 1, the cryosurgical apparatus of the present embodiment includes a probe 11 for freezing the affected part 30, a refrigerant holding container 12 that holds the refrigerant used in the probe in a liquid state under a pressurized condition, A condenser 14 that cools and condenses the gaseous refrigerant used in the probe, a refrigerant heating container 13 that heats the condensed refrigerant to be reused, and a refrigerant flow in the cryosurgical apparatus are controlled. A control device 18 is mainly provided.

  In the cryosurgical apparatus of the present embodiment, a first pipe 15 a that sends the refrigerant 1 in the liquid state from the refrigerant holding container 12 to the probe 11, and a second pipe that sends the refrigerant 2 in the gaseous state by the probe 11 to the condenser 14. Tube 15b and a bypass tube 15c connecting the first tube and the second tube. These pipes 15 preferably have an outer diameter of about 1 to 6 mm in accordance with the intended use and have a strength that can withstand a high-pressure or low-temperature refrigerant.

  The cryosurgical apparatus according to the present embodiment includes valves 16a, 16b, and 16c that open and close the refrigerant flow paths in the tubes 15a, 15b, and 15c, respectively. Further, a valve 16 d for opening and closing the refrigerant flow path is provided between the condenser 14 and the refrigerant heating container 13, and a valve 16 e for opening and closing the refrigerant flow path between the refrigerant heating container 13 and the refrigerant holding container 12. Is provided. These valves 16a to 16e are preferably solenoid valves in order to open and close at high speed and easily. By using the electromagnetic valve, a series of opening / closing operations can be sequenced by the control device 18.

  The refrigerant holding container 12 is a container that holds the refrigerant 1 in a liquid state under a pressurized condition. The refrigerant holding container 12 is preferably made of metal in order to withstand a high-pressure refrigerant. In order to repeatedly perform cryosurgery, the volume is preferably at least about 100 ml. The refrigerant holding container 12 includes a heater 17a for changing and maintaining the temperature of the refrigerant. The refrigerant is not particularly limited as long as it is pressurized at room temperature to be in a liquid state and can cool the probe to −20 ° C. or lower by reducing the pressure. Fluorocarbon, natural refrigerants such as propane, isobutane, ammonia, or a mixture thereof are preferable.

  The condenser 14 is a device for cooling and condensing the gaseous refrigerant 2 discharged from the probe 11. The condenser 14 includes a coolant 4 for cooling the refrigerant introduced into the condenser. As the coolant 4, any heat source can be used as long as a low temperature for cooling and liquefying the gaseous refrigerant 2 can be obtained. Further, the pressure in the condenser 14 is lower than the pressure in the refrigerant holding container 12. In particular, the pressure difference is preferably as large as possible so that the refrigerant easily flows from the refrigerant holding container 12 to the condenser 14. For example, the pressure in the condenser 14 is preferably set to a negative pressure (atmospheric pressure or lower). Specific examples of the coolant 4 include liquid nitrogen having a predetermined low temperature and high heat transfer performance.

  In the present embodiment, the inside of the condenser 14 maintains a negative pressure state at a low temperature by such a coolant 4. In order to efficiently liquefy the refrigerant 2 in the gaseous state, it is preferable to easily exchange heat with the coolant 4. Specifically, the coolant 4 is accommodated and the heat transfer part 14a that exchanges heat with the refrigerant 2 is made of a metal having high thermal conductivity, or an enlarged heat transfer surface such as a fin is attached to the heat transfer part 14a. Can be mentioned.

  The refrigerant heating container 13 is an apparatus that heats the liquid refrigerant 3 condensed by the condenser 14 in order to be reused by the refrigerant holding container 12. The refrigerant heating container 13 includes a heater 17b for heating the liquid refrigerant 3 introduced into the container. When the low-temperature negative pressure refrigerant 3 is heated, the refrigerant 3 becomes high pressure. Therefore, it is preferable that the refrigerant heating container 13 has strength capable of withstanding low temperature and high pressure. The condenser 14 and the refrigerant heating container 13 are provided with a heat insulating material 19 around them in order to keep the refrigerant at a low temperature.

  The control device 18 is configured to control the opening and closing of each valve 16 described above, and is configured to control the start and stop of each heater 17 of the refrigerant holding container 12 and the refrigerant heating container 13.

  As shown in FIG. 1, the probe 11 has a shape that can be used by piercing the affected part directly. The probe 11 will be described in more detail with reference to FIG.

  As shown in FIG. 2, the probe 11 has a double tube structure, and includes an inner tube 21 that acts as an orifice tube and an outer tube that serves as a probe body 22 that directly contacts the affected area. Both ends of the inner tube 21 are open, and one end of each of the inner tubes 21 is connected to the first tube 15a via a pressure-resistant joint 23a for withstanding the pressure of the refrigerant, and the other is near the closed tip of the outer tube 22. Located in. The opposite end of the outer tube 22 is open, and is connected to the second tube 15b via the pressure-resistant joint 23b in the same manner as the inner tube. As a material of the pressure | voltage resistant junction part 23, an epoxy-type adhesive agent and a metal gasket are mentioned, for example. Since the outer tube 22 is directly inserted into the affected area, in addition to strength, the outer tube 22 is required not to be toxic to the living body. Specifically, a stainless steel tube used for an injection needle is preferable.

  Depending on the cross-sectional area of the refrigerant flow path in the inner pipe 21, the length of the inner pipe 21, and the cross-sectional area ratios of the flow paths of the refrigerant in the inner pipe 21 and the outer pipe 22, the refrigerant flow rate, reduced pressure amount, and dryness Since it changes, the condensing performance of the condenser 14 and the minimum temperature and cooling capacity of the outer tube 22 can be appropriately designed. The inner pipe 21 preferably has such a thinness and length that the pressure of the refrigerant 1 in a liquid state can be reduced to about atmospheric pressure. Specifically, the inner tube 21 preferably has an outer diameter of 50 to 200 μm, a wall thickness of 10 to 40 μm, and a length of 100 to 500 mm. In particular, an outer diameter of 100 to 150 μm is more preferable. It is preferable that the outer tube 22 has such a size that the refrigerant is reduced to about atmospheric pressure in the inner tube 21 as described above. In particular, as shown in FIG. 2, the refrigerant 2 exiting the inner tube 21 flows through an annular channel formed between the outer wall of the inner tube 21 and the inner wall of the outer tube 22, so that the equivalent diameter of the annular channel is obtained. However, it must be larger than the inner diameter of the inner tube 21. Specifically, the outer tube 22 preferably has an outer diameter of 450 to 700 μm and an inner diameter of 250 to 350 μm. In particular, an outer diameter of 450 to 600 μm is more preferable. The thickness of the outer tube 22 is preferably 50 to 180 μm. The length of the outer tube 22 is preferably 100 to 200 mm. As shown in FIG. 2, in the present specification, the double tube structure is sufficient if a part of the inner tube 21 is inserted into the outer tube 22.

  According to the above configuration, as shown in FIG. 1, first, the refrigerant 1 in a liquid state is supplied into the refrigerant holding container 12 at room temperature and high pressure. Further, the coolant 4 is introduced into the condenser 14 and the inside of the condenser 14 is maintained in a low-temperature negative pressure state. At this time, the valve 16b of the second pipe 15b is kept open, and the other valves 16a, 16c, 16d, and 16e are all closed.

  And in order to start cooling of the probe 11, the valve 16a of the 1st pipe | tube 15a is opened. As a result, the liquid state refrigerant 1 flows from the refrigerant holding container 12 to the probe 11. As shown in FIG. 2, in the probe 11, the liquid state refrigerant 1 flows into the inner tube 21, is decompressed and expanded by the orifice action, and changes to a two-phase flow. And when it flows out from the inner tube 21 to the outer tube 22, it takes the heat from the outer tube 22 which is the probe body and vaporizes it, and becomes a refrigerant 2 in a gaseous state at a low temperature. The refrigerant 2 in the gaseous state flows through the annular flow path between the inner tube 21 and the outer tube 21, and then flows to the condenser 14 through the second tube 15b. In the condenser 14, the refrigerant 2 in the gas state is cooled and condensed by the coolant 4, and is stored as a refrigerant 3 in the liquid state at the bottom of the condenser 14.

  In this way, the refrigerant 1 in a liquid state at normal temperature and pressure is discharged into the outer tube 22 after passing through the inner tube 21 of the probe 11, whereby the refrigerant 1 is depressurized and lowered in temperature, and the outer tube 22, which is the probe body, is removed. It can be cooled to −20 ° C. or lower, and thus cryosurgery is possible. Further, since the refrigerant 1 is at a normal temperature until it flows into the inner tube 21 of the probe 11, it is not necessary to insulate the first tube 15 a through which the refrigerant flows from the refrigerant holding container 12 to the probe 11. Further, since the low-temperature gaseous refrigerant discharged to the outer tube 22 has a small heat capacity, it immediately becomes the same temperature as the ambient temperature, and therefore the second tube 15b in which the refrigerant flows from the probe 11 to the condenser 14. There is no need to insulate. Therefore, it is not necessary to insulate the refrigerant tube 15 until it reaches the affected area, so that cryosurgery in the body is facilitated.

  Next, in order to stop the cooling of the probe 11, the valve 16a of the first pipe 15a is closed and the valve 16c of the bypass pipe 15c is opened. By opening the valve 16c, the refrigerant 1 in the first pipe 15a is forced to flow into the condenser 14 via the bypass pipe 15c. As a result, the flow of the refrigerant 1 into the probe 11 immediately stops, and the temperature of the probe 11 also rapidly rises from −20 ° C. or lower to the freezing point of water that is the main component of the living tissue (ie, 0 ° C.). Thereafter, the temperature of the probe 11 gradually rises to room temperature by the self-heating mechanism of the surrounding living tissue. By operating each valve 16 in this way, the temperature drop and rise of the probe 11 can be quickly controlled. Therefore, by repeating this operation, the affected part can be repeatedly cooled, and the cell necrosis rate can be improved.

  The above cooling and cooling stop operations can be continuously repeated until the refrigerant 1 stored in the refrigerant holding container 12 runs out. After the refrigerant 1 is exhausted in the refrigerant holding container 12, an operation of reusing the refrigerant 3 stored in the condenser 14 is performed.

  In the operation of reusing the refrigerant, first, the valves 16a and 16b of the first and second pipes 15a and 15b are opened, the refrigerant 1 remaining in the refrigerant holding container 12 is caused to flow to the condenser 14, and the refrigerant holding container 12 is used. The inside is made the same pressure as the condenser 14. Thereafter, the valves 16a and 16b are closed, and the valve 16d between the condenser 14 and the refrigerant heating container 13 is opened. And after introduce | transducing the refrigerant | coolant 3 of the liquid state in the condenser 14 in the refrigerant | coolant heating container 13, the valve 16d is closed and a refrigerant | coolant is heated using the heater 17b. The refrigerant is heated to the temperature of the refrigerant in the original refrigerant holding container 12, for example, room temperature. As a result, the low-pressure negative pressure liquid refrigerant 3 changes to a normal temperature high pressure liquid refrigerant 1.

  Next, the valve 16 e between the refrigerant heating container 13 and the refrigerant holding container 12 is opened, and the refrigerant 1 in a liquid state at normal temperature and high pressure in the refrigerant heating container 13 is supplied into the refrigerant holding container 12. Then, by closing the valve 16e, the initial state is restored, and the probe 11 can be cooled again. By reusing the refrigerant in this way, the refrigerant can be used semipermanently without discharging the refrigerant to the atmosphere. In addition, since the compressor is not used in the process of reusing the refrigerant, the entire apparatus can be reduced in size.

  Although the embodiment shown in FIGS. 1 and 2 has been described, the present invention is not limited to this. For example, in addition to the shape shown in FIG. 2, the probe 11 may have a shape in which the outer tube 32 is curved into a circular shape as shown in FIG. 3, for example. In the case of this embodiment, both ends of the outer tube 32 are open, one is connected to the inner tube 31 via the pressure-bonding portion 33, and the other is connected to the second tube 15b. Both ends of the inner tube 31 are also open. One is connected to the first tube 15 a via the pressure-bonding portion 33 and the end of the outer tube 32, and the other is located in the middle portion of the outer tube 32. The outer diameter, inner diameter, and length of the inner tube 31 are the same as in the configuration of FIG. On the other hand, the outer tube 32 only needs to have an inner diameter of the outer tube 32 larger than the inner diameter of the inner tube 31 because the refrigerant 2 coming out of the inner tube 31 passes through the outer tube 32. Specifically, the outer tube 32 preferably has an outer diameter of 200 to 500 μm, a wall thickness of 10 to 180 μm, and a length of 100 mm to 500 mm.

  As described above, by arbitrarily deforming the shape of the outer tube 32, it is possible to freeze a specific part in a linear shape. Further, the outer tube 32 can be made flexible. In this case, the material of the outer tube 32 is not particularly limited as long as it has strength and flexibility at low temperatures, and biocompatibility, and examples thereof include a silicon tube.

  In the embodiment shown in FIG. 1, the refrigerant heating container 13 is provided, but the present invention is not particularly limited to this. For example, since the refrigerant may be heated at room temperature, without using a heater, for example, by exchanging heat between the refrigerant and the atmosphere or air, the low-temperature negative pressure refrigerant 3 in the condenser 14 is changed to the original normal temperature. The refrigerant can be returned to the high-pressure refrigerant 1. Thus, an arbitrary heat source can be used for heating. Further, the low-temperature negative pressure refrigerant 3 may be heated in the condenser 14. For example, the coolant 4 may be taken out from the condenser 14 and the refrigerant 3 may be heated by an arbitrary heat source. When the refrigerant 1 at room temperature and high pressure is obtained, the refrigerant 1 may be supplied directly from the condenser 14 to the refrigerant holding container 12.

  With the cryosurgical apparatus having the configuration shown in FIG. 4, a test for cooling the probe and an operation for stopping the cooling was performed. The probe having the configuration shown in FIG. 2 was used. Two types of stainless steel tubes having outer and inner diameters of 150 μm, 70 μm, 550 μm, and 300 μm were used as the inner tube and the outer tube of the double tube structure probe, respectively. As the refrigerant, HFC-23 (boiling point under atmospheric pressure: −82.1 ° C.), which is one of alternative chlorofluorocarbons having an ozone depletion potential (ODP) of 0, was used. Liquid nitrogen (boiling point under atmospheric pressure: −196 ° C.) was used for the coolant 4 of the condenser 14.

  In this test, first, a liquid refrigerant is stored in the refrigerant holding container 12 at about 42 atm. The valve 16a of the first pipe 15a, the valve 16c of the bypass pipe 15c, and the valve between the refrigerant holding container 12 and the condenser 14 are stored. 16d was closed and the valve 16b of the second pipe 15b was opened. Moreover, the pressure in the condenser 14 became a saturation pressure at the liquid nitrogen temperature of HFC-23, and was about 0 atm. The probe 11 was inserted into agar at about 37 ° C. This is for simulating a living tissue.

  Then, as an operation for starting the cooling of the probe 11, the valve 16 a of the first pipe 15 a was opened, and the liquid state refrigerant 1 was caused to flow into the probe 11. The time history of the temperature of the probe 11 is shown in FIG. The refrigerant 1 in the liquid state was depressurized while passing through the inner tube 21, changed to a two-phase flow, and took the heat of the agar in the outer tube 22 and vaporized. It can be seen from FIG. 5 that the surface of the probe 11 has reached about −25 ° C. in 10 seconds from the cooling start operation. Actually, a frozen region was confirmed around the probe 11.

  Next, a cooling stop operation was performed 20 seconds after the start of cooling. First, the valve 16a of the first pipe 15a was closed, and the valve 16c of the bypass pipe 15c was opened. By opening the valve 16c, the refrigerant 1 flowing in the first pipe 15a and the probe 11 flowed into the condenser 14 simultaneously and rapidly. As shown in FIG. 5, the surface temperature of the probe 11 rose to 0 ° C. immediately after the cooling stop operation. After maintaining the temperature at 0 ° C. for a while, the frozen region disappeared completely about 30 seconds after the cooling stop operation, and the temperature of the probe 11 increased.

1, 2, 3 Refrigerant 4 Coolant 11 Probe 12 Refrigerant holding container 13 Refrigerant heating container 14 Condenser 15 Tube 16 Valve 17 Heater 18 Controller 19 Heat insulating material 21, 31 Inner tube 22, 32 Outer tube 23, 33 Pressure resistant joint 30 affected area

Claims (4)

A probe for freezing the affected area, a refrigerant holding container for holding a refrigerant used in the probe in a liquid state under a pressurized condition, a condenser for cooling and condensing the refrigerant in a gaseous state, and a liquid state by condensation. Heat is applied to the resulting refrigerant to obtain the original refrigerant temperature in the refrigerant holding container, and the refrigerant heating container returns the liquid refrigerant to the liquid state under the original pressurized condition in the refrigerant holding container; A first pipe for sending liquid refrigerant to the probe, a second pipe for sending the gaseous refrigerant from the probe to the condenser, and sending the condensed refrigerant from the condenser to the refrigerant heating container. A cryosurgical apparatus comprising a first flow path and a second flow path for sending a refrigerant in a liquid state from the refrigerant heating container to the refrigerant holding container under the pressurized condition , wherein the probe is an inner tube And outer tube The inner tube depressurizes the liquid refrigerant from the first tube, and the outer tube has an outer surface in contact with the affected area, and the inner tube A cryosurgical apparatus in which a decompressed refrigerant flows and takes heat from the affected area to vaporize the refrigerant.   The cryosurgical apparatus according to claim 1, wherein the inner tube of the probe has an outer diameter of 50 to 200 µm and a wall thickness of 10 to 40 µm, and the outer tube of the probe has an outer diameter of 200 to 700 µm and a wall thickness of 10 to 180 µm.   The cryosurgical apparatus according to claim 1 or 2, further comprising a bypass pipe that connects the first pipe and the second pipe without passing through the probe, and the bypass pipe includes a valve that can be opened and closed. A probe for freezing the affected area, a refrigerant holding container for holding a refrigerant used in the probe in a liquid state under a pressurized condition, a condenser for cooling and condensing the refrigerant in a gaseous state, and a liquid state by condensation. A refrigerant heating container for applying heat to the refrigerant, a first pipe for sending the liquid refrigerant from the refrigerant holding container to the probe, and a second pipe for sending the gas refrigerant from the probe to the condenser A pipe, a first flow path for sending the condensed refrigerant from the condenser to the refrigerant heating container, and a second flow path for sending the heat added from the refrigerant heating container to the refrigerant holding container. A temperature control method for a cryosurgical apparatus comprising:
The refrigerant holding container communicates with the condenser via the first and second pipes and the probe, whereby the liquid refrigerant is sent to the probe and the probe is cooled by vaporizing the refrigerant. A step of stopping cooling of the probe by disabling the refrigerant holding container from the probe and communicating the first tube with the condenser without passing through the probe; and the refrigerant heating A step of applying heat to the liquid refrigerant in the container to bring the temperature of the original refrigerant in the refrigerant holding container back to the liquid refrigerant under the original pressurized condition in the refrigerant holding container; A method for controlling the temperature of a cryosurgical apparatus.

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