Transmission device and method for assisting small animals in autonomously breathing hyperpolarized gas

Abstract

The invention discloses a transmission device for assisting a small animal to autonomously breathe hyperpolarized gas, which is characterized in that a sealed breathing mask is used for replacing a trachea cannula, and stable pressure of atmospheric pressure at the breathing mask is used for replacing periodic pressure change under high-pressure forced ventilation at the cannula; the animal spontaneous respiration gas amount is used for replacing the manually set fixed gas amount, and the state of inhaled gas is controlled under spontaneous respiration to replace fully controlled mechanical ventilation in the respiration process; the invention further discloses a method for assisting the small animal in autonomously breathing the hyperpolarized gas, the device can supply the gas amount required by autonomously breathing to the experimental animal according to the self-breathing state of the experimental animal, and the gas amount inhaled by the experimental animal each time is determined by the self-breathing state, so that the experimental animal can autonomously breathe in a free state; lung expansion in an abnormal breathing state can be avoided, so that a more accurate ventilation function and qi-blood exchange function evaluation result is obtained.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of magnetic resonance imaging, and particularly relates to a device for assisting small animals to inhale hyperpolarized gas, and a method for assisting small animals to inhale hyperpolarized gas, which are suitable for assisting small animals to inhale hyperpolarized gas in hyperpolarized inert gas magnetic resonance imaging experiments. BACKGROUND

[0002] Hyperpolarized gas magnetic resonance imaging (MRI) is a rapidly developing imaging method with great potential. Through spin exchange optical pumping technology, the nuclear spin polarization degree of inert gas is increased by 4-5 orders of magnitude relative to the thermal equilibrium state. Through the method of hyperpolarized gas magnetic resonance, the low water proton density in the lungs is compensated for, and the sensitivity of the magnetic resonance signal is greatly improved, realizing the visualization of the structure and function of the lungs.

[0003] Medical animal experiments are an important link for scientific research to move from the molecular and cellular levels to clinical research. Small animal disease models are often used for preclinical experimental research of hyperpolarized gas lung magnetic resonance imaging to evaluate the feasibility and effectiveness of new technologies and methods. Hyperpolarized gas MRI usually requires data acquisition during breath-holding after inhaling hyperpolarized gas. In animal experiments, since animals cannot complete the breath-holding command autonomously, a gas breathing device is needed to control the breathing process to complete the sampling. In the prior art, small animal hyperpolarized gas imaging requires oral or tracheal intubation of the small animal, and a positive pressure ventilation method is used to control the breathing state and ensure minimal loss of polarization degree during gas transmission. However, this invasive mechanical breathing control will have some impact on the animal's respiratory system, affecting the reliability and repeatability of the experimental results. In addition, this breathing control can change the animal's own free breathing pattern, which may interfere with the observation of the animal's natural breathing pattern. For example, the respiratory system of birds is very different from that of mammals. They have evolved a more complex respiratory system that includes lungs and air sacs. The direction and pattern of airflow under free breathing are controlled by the contraction and relaxation of the complex airway structure and the nine air sacs. At this time, the use of a traditional intubation and positive pressure ventilation transmission system will change the airflow pattern between the air sacs and the lungs, thereby affecting the observation of the natural breathing pattern of birds. In addition, the tidal volume and breathing rate of test animals of different weights and different disease severity will differ. If they are subjected to mechanical breathing control with fixed parameters, it is likely that the lungs will be inflated in an abnormal breathing state, thereby affecting the evaluation of the rat's ventilation function and gas exchange function. Compared with such a gas transmission device that simply controls the passive breathing of the subject, the present application is closer to the free breathing state of the subject and controls the inhalation and exhalation of different gases according to the free breathing state, and is suitable for assisting small animals to inhale hyperpolarized gas in hyperpolarized gas magnetic resonance imaging experiments.

[0004] Most of the prior art is a controlled quantitative gas supply method, and in the implementation process, the subject inhales a set amount of gas by means of autonomous breathing, or can only be actively controlled by the subject, and is not suitable for respiratory control of animals other than humans. SUMMARY

[0005] The present application aims at the above-mentioned problems existing in the prior art, and provides a device for assisting small animals to breathe hyperpolarized gas autonomously, and a method for assisting small animals to breathe hyperpolarized gas autonomously.

[0006] The above-mentioned purposes of the present application are achieved by the following technical means: A device for assisting small animals to breathe hyperpolarized gas autonomously, comprising a hyperpolarized gas gas circuit, an oxygen gas circuit, an exhalation gas circuit, a gas mixer, a bidirectional gas flow meter, a control console, a data collector, and a breathing mask, the oxygen gas circuit, the hyperpolarized gas gas circuit, the exhalation gas circuit, and the gas supply pipe of the breathing mask are all in communication with the gas mixer, the exhalation gas circuit is also in communication with the outside world, the oxygen gas circuit, the hyperpolarized gas gas circuit, and the exhalation gas circuit are all provided with electromagnetic valves and relays, the electromagnetic valves of each gas circuit are respectively connected with the relays of the corresponding gas circuit through signal transmission lines, the bidirectional gas flow meter is arranged on the gas supply pipe of the breathing mask, the data collector is connected with the control console through a USB data line, the data collector further comprises a plurality of analog input channels and a plurality of digital output channels, the control interfaces of the relays of each gas circuit are respectively connected with one digital output channel in correspondence through signal transmission lines, and one analog input channel of the data collector is connected with the bidirectional gas flow meter through a signal transmission line.

[0007] The hyperpolarized gas gas circuit comprises a pressure regulating gas circuit pipeline and a switch control gas circuit pipeline as described above; The two ends of the pressure regulating gas circuit pipeline are respectively in communication with a nitrogen cylinder and a sealed organic glass box, a pressure regulating valve and a pressure gauge are sequentially arranged on the pressure regulating gas circuit pipeline from the nitrogen cylinder to the sealed organic glass box, a hyperpolarized gas sampling bag is arranged in the sealed organic glass box, a gas outlet is formed on the sealed organic glass box, the open bag edge of the hyperpolarized gas sampling bag is sealingly connected with the box edge of the gas outlet of the sealed organic glass box, the opening of the hyperpolarized gas sampling bag is connected with the gas inlet pipeline of the two-way gas control valve through a Luer connector, the gas outlet pipeline of the two-way gas control valve is in communication with the gas mixer, and a one-way valve is arranged on the gas outlet pipeline of the two-way gas control valve. One end of the switch control gas circuit pipeline is in communication with the nitrogen cylinder, the other end of the switch control gas circuit pipeline is connected with the control port of the two-way gas control valve, and the electromagnetic valve of the hyperpolarized gas gas circuit is arranged on the switch control gas circuit pipeline.

[0008] As described above, the oxygen supply line includes an oxygen supply pipeline, the inlet of which is connected to an oxygen cylinder. A pressure regulating valve, a pressure gauge, and a check valve are sequentially installed along the oxygen supply pipeline from the oxygen cylinder toward the gas mixer.

[0009] It also includes a temperature sensor, and another analog input channel of the data acquisition unit is connected to the temperature sensor via a signal transmission line.

[0010] As described above, the switching power supply is connected to the solenoid valves and relays of each air circuit via signal transmission lines.

[0011] A method for assisting small animals in spontaneous breathing of hyperpolarized gas, utilizing a transmission device for assisting small animals in spontaneous breathing of hyperpolarized gas as described above, includes the following steps: Step 1: Before performing hyperpolarized gas magnetic resonance imaging (HMR) scanning, connect the data acquisition device to the control console. After anesthetizing the experimental animal, put a breathing mask on it and place a temperature sensor inside the animal. Keep the oxygen and hyperpolarized gas pathways closed in the control console, open the expiratory pathway, and allow the animal to breathe outside air autonomously. The control console integrates the gas flow rate measured by the bidirectional gas flow meter to obtain and display the animal's respiratory waveform. The derivative changes of the respiratory waveform are obtained in real time through the animal's respiratory waveform. Step 2: Perform hyperpolarized gas magnetic resonance imaging (HMR) scanning. First, perform oxygen respiration flushing. Keep the hyperpolarized gas path closed at the control console. Control the opening and closing of the oxygen and expiratory gas paths by monitoring the animal's respiratory waveform. The experimental animal breathes oxygen spontaneously: when the derivative of the respiratory waveform changes from negative to positive at the control console, the control console opens the oxygen path and closes the expiratory gas path, and the experimental animal inhales oxygen spontaneously; when the derivative of the respiratory waveform changes from positive to negative at the control console, the control console opens the expiratory gas path and closes the oxygen path, and the experimental animal exhales spontaneously. Step 3: After oxygen respiration flushing is completed, keep the oxygen supply closed. The control console monitors the animal's respiratory waveform to control the opening and closing of the oxygen and expiratory supply lines. The experimental animal breathes hyperpolarized gas autonomously: when the control console detects that the derivative of the respiratory waveform changes from negative to positive, the control console opens the hyperpolarized gas supply line and closes the expiratory supply line, and the experimental animal inhales the hyperpolarized gas autonomously; when the control console detects that the derivative of the respiratory waveform changes from positive to negative, the control console opens the expiratory supply line and closes the hyperpolarized gas supply line, and the experimental animal exhales autonomously. Step 4: During hyperpolarized gas magnetic resonance imaging scanning, when the experimental animal holds its breath, the control console sets the opening and closing of the gas path according to the respiratory waveform and the set breath-holding time: when the control console detects that the derivative of the respiratory waveform changes from positive to zero, the control console closes the oxygen gas path, the hyperpolarized gas path, and the expiratory gas path, the peak value of the respiratory waveform remains unchanged, and the experimental animal is in a breath-holding state; after the set breath-holding time, the control console opens the expiratory gas path, and the experimental animal exhales spontaneously.

[0012] Compared with the prior art, the present invention has the following advantages: (1) In the experiment of hyperpolarized gas MRI scanning, the device of the present invention can supply the experimental animal with the amount of gas required for autonomous breathing according to the experimental animal's own respiratory state. The amount of gas inhaled by the experimental animal each time is determined by its own respiratory state, so that the experimental animal can perform autonomous breathing in a free state. The present invention uses a sealed breathing mask to replace endotracheal intubation, uses the stable atmospheric pressure at the breathing mask to replace the periodic pressure change under high pressure forced ventilation at the intubation, uses the amount of gas inhaled by the animal to replace the fixed amount of gas set by the human, and uses the state of controlling the inhaled gas under autonomous breathing to replace the fully controlled mechanical ventilation of the breathing process.

[0013] (2) The present invention fully considers that experimental animals of different weights and different disease severity will have different tidal volumes and respiratory rates. The present invention enables experimental animals to breathe autonomously in a free state, which can avoid lung expansion in an abnormal breathing state, thereby obtaining more accurate assessment results of ventilation function and gas exchange function.

[0014] (3) At the same time, for birds or other non-mammalian animals with complex respiratory systems, the method of assisting experimental animals to breathe autonomously in this invention is more conducive to obtaining the airflow pattern of experimental animals in their natural state. In addition, the device of this invention can also actively control the animal to hold its breath according to the animal's breathing state when necessary, thus retaining the control function of passive breathing mode. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the device of the present invention; Figure 2 This is a flowchart of the method of the present invention; Figure labels and corresponding component names: 1—Control console; 2—Data acquisition unit; 3—First relay; 4—Second relay; 5—Third relay; 6—First solenoid valve; 7—Second solenoid valve; 8—Third solenoid valve; 9—Switching power supply; 10—Temperature sensor; 11—Respiratory mask; 12—Oxygen cylinder; 13—Nitrogen cylinder; 14—First pressure regulating valve; 15—Second pressure regulating valve; 16—First check valve; 17—Second check valve; 18—Sealed plexiglass box; 19—Hyperpolarized gas sampling bag; 20—Two-way gas control valve; 21—Two-way gas flow meter; 22—First pressure gauge; 23—Second pressure gauge; 24—Gas mixer. Detailed Implementation

[0016] To facilitate understanding and implementation of the present invention by those skilled in the art, the present invention will be further described in detail below with reference to embodiments. The embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0017] Example 1: A device for transmitting hyperpolarized gas to assist small animals in autonomous breathing includes multiple gas paths, namely a hyperpolarized gas path, an oxygen (O2) path, and an exhalation path. It also includes a gas mixer 24, a bidirectional gas flow meter 21, a control console 1, a data acquisition device 2 (such as a data acquisition card), solenoid valves, relays, and a breathing mask 11. The supply pipes for the oxygen path, hyperpolarized gas path, exhalation path, and breathing mask 11 are all connected to the gas mixer 24. The exhalation path is also connected to the outside environment. The oxygen path is equipped with a solenoid valve and a relay, respectively labeled as first solenoid valve 6 and first relay 3. The hyperpolarized gas path is equipped with a solenoid valve and a relay, respectively labeled as second solenoid valve 7 and second relay 4. The exhalation path is equipped with a... A solenoid valve and a relay are respectively designated as the third solenoid valve 8 and the third relay 5. The first solenoid valve 6, the second solenoid valve 7, and the third solenoid valve 8 are connected to the load interfaces of the first relay 3, the second relay 4, and the third relay 5 respectively via signal transmission lines. A bidirectional gas flow meter 21 is installed on the air supply pipe of the breathing mask 11. The data acquisition unit 2 is connected to the control console 1 via a USB data cable. The data acquisition unit 2 also includes two analog input channels and three digital output channels. The three digital output channels of the data acquisition unit 2 are respectively connected to the control interfaces of the first relay 3, the second relay 4, and the third relay 5. One of the analog input channels of the data acquisition unit 2 is connected to the bidirectional gas flow meter 21 via a signal transmission line.

[0018] The hyperpolarized gas path includes a pressure regulating gas path pipeline and a switch control gas path pipeline; The two ends of the pressure regulating gas pipeline are connected to the nitrogen cylinder 13 and the sealed plexiglass box 18, respectively. A pressure regulating valve and a pressure gauge are sequentially installed in the direction from the nitrogen cylinder 13 to the sealed plexiglass box 18, respectively referred to as the second pressure regulating valve 15 and the second pressure gauge 23. The hyperpolarized gas sampling bag 19 is placed in the sealed plexiglass box 18. The sealed plexiglass box 18 has a gas outlet. The opening of the hyperpolarized gas sampling bag 19 is sealed to the edge of the gas outlet of the sealed plexiglass box 18. The opening of the hyperpolarized gas sampling bag 19 is connected to the gas inlet pipeline of the two-way gas control valve 20 through a Luer connector. The gas outlet pipeline of the two-way gas control valve 20 is connected to the gas mixer 24. A one-way valve is installed on the gas outlet pipeline of the two-way gas control valve 20, referred to as the second one-way valve 17. One end of the switch control gas pipeline is connected to nitrogen cylinder 13, and the other end of the switch control gas pipeline is connected to the control port of two-way gas control valve 20. The second solenoid valve 7 is installed on the switch control gas pipeline.

[0019] The oxygen supply line includes an oxygen supply pipeline. The inlet end of the oxygen supply pipeline is connected to the oxygen cylinder 12. A pressure regulating valve, a pressure gauge, and a check valve are sequentially arranged in the direction from the oxygen cylinder 12 to the gas mixer 24. These are referred to as the first pressure regulating valve 14, the first pressure gauge 22, and the first check valve 16, respectively.

[0020] It also includes a temperature sensor 10. Another analog input channel of the data acquisition unit 2 is connected to the temperature sensor 10 via a signal transmission line. The temperature sensor 10 can be placed in the experimental animal before performing hyperpolarized gas MRI scanning. The temperature sensor 10 transmits the experimental animal's body temperature data to the control console 1 through the data acquisition unit 2, thereby monitoring the experimental animal's body temperature in real time.

[0021] The switching power supply 9 is connected to the power interface of the first relay 3, the power interface of the second relay 4, and the power interface of the third relay 5 via signal transmission lines; the ground interfaces of the first solenoid valve 6 and the first relay 3, the ground interfaces of the second solenoid valve 7 and the second relay 4, and the ground interfaces of the third solenoid valve 8 and the third relay 5 are all connected to the ground terminal of the switching power supply 9 via signal transmission lines; the switching power supply 9 is used to supply power to the relays and solenoid valves.

[0022] In this embodiment, all relays are solid-state relays.

[0023] The bidirectional gas flow meter 21 is used to monitor the gas flow rate during the respiration of experimental animals in real time, and transmits the gas flow rate data to the control console 1 through the data acquisition unit 2. The control console 1 acquires the respiratory waveform of the experimental animals based on the real-time gas flow rate data. The control console 1 adjusts the output level of the three digital output channels of the data acquisition unit 2 according to the respiratory waveform of the experimental animals, and controls the opening and closing of the corresponding relays connected to each digital output channel, thereby controlling the opening and closing of the corresponding solenoid valves, and then controlling the opening and closing of the gas connected to the relays and solenoid valves.

[0024] Example 2: A method for assisting small animals in spontaneous breathing of hyperpolarized gas, utilizing the hyperpolarized gas transmission device for assisting small animals in spontaneous breathing as described in Example 1 above, includes the following steps: Step 1: Before performing hyperpolarized gas magnetic resonance imaging (HMI) scanning, connect the data acquisition unit 2 to the control console 1, open the LabVIEW (Laboratory Virtual Instrument Engineering Workbench) program in the control console 1, anesthetize the experimental animal, put a breathing mask 11 on the experimental animal, and place the temperature sensor 10 in the experimental animal to monitor the body temperature of the experimental animal in real time. Keep the oxygen gas path and the hyperpolarized gas path closed, open the expiratory gas path, and let the animal breathe outside air on its own. The control console 1 integrates the gas flow rate measured by the bidirectional gas flow meter 21 in real time to obtain and display the respiratory waveform of the experimental animal. The derivative change of the respiratory waveform is obtained in real time through the respiratory waveform of the experimental animal. Step 2: Perform hyperpolarized gas magnetic resonance imaging (HMR) scanning. First, perform oxygen respiration flushing. Keep the hyperpolarized gas path closed on console 1. Control the opening and closing of the oxygen and expiratory gas paths by monitoring the animal's respiratory waveform, so that the experimental animal can breathe oxygen autonomously: When console 1 detects that the derivative of the respiratory waveform changes from negative to positive, that is, when the bidirectional gas flow meter 21 measures a positive gas flow rate, console 1 opens the oxygen path and closes the expiratory gas path, and the experimental animal inhales oxygen autonomously; when console 1 detects that the derivative of the respiratory waveform changes from positive to negative, that is, when the bidirectional gas flow meter 21 measures a positive gas flow rate, console 1 opens the expiratory gas path and closes the oxygen path, and the experimental animal exhales autonomously. Step 3: After oxygen respiration flushing is completed, keep the oxygen supply closed. Control console 1 controls the opening and closing of the oxygen and expiratory supply lines by monitoring the animal's respiratory waveform, allowing the experimental animal to breathe hyperpolarized gas autonomously: when control console 1 detects that the derivative of the respiratory waveform changes from negative to positive, control console 1 opens the hyperpolarized gas supply line and closes the expiratory supply line, allowing the experimental animal to inhale hyperpolarized gas autonomously; when control console 1 detects that the derivative of the respiratory waveform changes from positive to negative, control console 1 opens the expiratory supply line and closes the hyperpolarized gas supply line, allowing the experimental animal to exhale autonomously. Step 4: During hyperpolarized gas magnetic resonance imaging scanning, when the experimental animal needs to hold its breath, console 1 controls the opening and closing of the airway according to the respiratory waveform and the set breath-holding time: when console 1 detects that the derivative of the respiratory waveform changes from positive to zero, console 1 closes the oxygen airway, the hyperpolarized gas airway, and the expiratory airway, while the peak value of the respiratory waveform remains unchanged, so that the experimental animal is in a breath-holding state; after the set breath-holding time, console 1 opens the expiratory airway, so that the experimental animal can exhale voluntarily.

[0025] During the experiment of hyperpolarized gas magnetic resonance imaging scanning, the pressure at the sealed breathing mask 11 is always maintained at atmospheric pressure. The device of the present invention can supply the experimental animal with the amount of gas required for autonomous breathing according to the experimental animal's own breathing state. The amount of gas inhaled by the experimental animal each time is determined by its own breathing state, so that the experimental animal can perform autonomous breathing in a free state. This invention takes into full account the differences in tidal volume and respiratory rate of experimental animals with different weights and disease severity. This invention allows experimental animals to breathe spontaneously in a free state, which can avoid lung expansion caused by abnormal breathing, thereby obtaining more accurate assessment results of ventilation function and gas exchange function.

[0026] Meanwhile, for birds or other non-mammalian animals with complex respiratory systems, the method of assisting experimental animals to breathe autonomously in this invention is more conducive to obtaining the airflow pattern of experimental animals in their natural state. In addition, the device of this invention can also actively control the animal to hold its breath according to the animal's breathing state when necessary, thus retaining the control function of passive breathing mode.

[0027] It should be noted that the embodiments described in this invention are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains can make various modifications or additions to the described embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A device for transmitting hyperpolarized gas to assist small animals in autonomous breathing, comprising a hyperpolarized gas path, characterized in that, It also includes an oxygen gas path, an exhalation gas path, a gas mixer (24), a two-way gas flow meter (21), a control console (1), a data acquisition unit (2), and a breathing mask (11). The supply pipes of the oxygen gas path, the hyperpolarized gas path, the exhalation gas path, and the breathing mask (11) are all connected to the gas mixer (24). The exhalation gas path is also connected to the outside. The oxygen gas path, the hyperpolarized gas path, and the exhalation gas path are all equipped with solenoid valves and relays. The solenoid valves of each gas path are connected to the relays of the corresponding gas path through signal transmission lines. The supply pipe of the breathing mask (11) is equipped with a two-way gas flow meter (21). The data acquisition unit (2) is connected to the control console (1) through a USB data cable. The data acquisition unit (2) also includes multiple analog input channels and multiple digital output channels. The control interface of the relays of each gas path is connected to a corresponding digital output channel through a signal transmission line. One of the analog input channels of the data acquisition unit (2) is connected to the two-way gas flow meter (21) through a signal transmission line.

2. The device for transmitting hyperpolarized gas to assist autonomous breathing in small animals according to claim 1, characterized in that, The hyperpolarized gas path includes a pressure regulating gas path pipeline and a switch control gas path pipeline; The two ends of the pressure regulating gas pipeline are connected to the nitrogen cylinder (13) and the sealed plexiglass box (18) respectively. A pressure regulating valve and a pressure gauge are sequentially installed in the direction from the nitrogen cylinder (13) to the sealed plexiglass box (18). The hyperpolarized gas sampling bag (19) is placed in the sealed plexiglass box (18). A gas outlet is opened on the sealed plexiglass box (18). The opening edge of the hyperpolarized gas sampling bag (19) is sealed and connected to the edge of the gas outlet of the sealed plexiglass box (18). The opening of the hyperpolarized gas sampling bag (19) is connected to the gas inlet pipeline of the two-way gas control valve (20) through a Luer connector. The gas outlet pipeline of the two-way gas control valve (20) is connected to the gas mixer (24). A one-way valve is installed on the gas outlet pipeline of the two-way gas control valve (20). One end of the switch control gas pipeline is connected to a nitrogen cylinder (13), and the other end of the switch control gas pipeline is connected to the control port of a two-way gas control valve (20). The solenoid valve of the hyperpolarized gas pipeline is installed on the switch control gas pipeline.

3. The device for transmitting hyperpolarized gas to assist autonomous breathing in small animals according to claim 2, characterized in that, The oxygen supply line includes an oxygen supply pipeline, the inlet of which is connected to an oxygen cylinder (12). A pressure regulating valve, a pressure gauge, and a check valve are sequentially arranged along the oxygen supply pipeline from the oxygen cylinder (12) toward the gas mixer (24).

4. The device for transmitting hyperpolarized gas to assist autonomous breathing in small animals according to claim 3, characterized in that, It also includes a temperature sensor (10), and another analog input channel of the data acquisition unit (2) is connected to the temperature sensor (10) via a signal transmission line.

5. The device for transmitting hyperpolarized gas to assist autonomous breathing in small animals according to claim 4, characterized in that, The switching power supply (9) is connected to the solenoid valves and relays of each air circuit through signal transmission lines.

6. A method for assisting small animals in spontaneous respiration of hyperpolarized gas, utilizing the transmission device for assisting small animals in spontaneous respiration of hyperpolarized gas as described in claim 5, characterized in that, Includes the following steps: Step 1: Before performing hyperpolarized gas magnetic resonance imaging, connect the data acquisition device (2) to the control console (1), anesthetize the experimental animal and put a breathing mask (11) on the experimental animal, and then place the temperature sensor (10) in the experimental animal. The control console (1) keeps the oxygen gas path and the hyperpolarized gas path closed, opens the expiratory gas path, and the animal breathes the outside air on its own. The control console (1) integrates the gas flow measured by the bidirectional gas flow meter (21) to obtain and display the respiratory waveform of the experimental animal. The derivative change of the respiratory waveform is obtained in real time through the respiratory waveform of the experimental animal. Step 2: Perform hyperpolarized gas magnetic resonance imaging scan. First, perform oxygen breathing flushing. Keep the hyperpolarized gas path closed in the control console (1). Control the opening and closing of the oxygen path and expiratory path by monitoring the animal's breathing waveform. The experimental animal breathes oxygen autonomously: When the control console (1) detects that the derivative of the breathing waveform changes from negative to positive, the control console (1) opens the oxygen path and closes the expiratory path, and the experimental animal inhales oxygen autonomously; When the control console (1) detects that the derivative of the breathing waveform changes from positive to negative, the control console (1) opens the expiratory path and closes the oxygen path, and the experimental animal exhales autonomously. Step 3: After the oxygen breathing flushing is completed, keep the oxygen gas path closed. The control console (1) controls the opening and closing of the oxygen gas path and the expiratory gas path by monitoring the animal's breathing waveform. The experimental animal breathes hyperpolarized gas autonomously: When the control console (1) detects that the derivative of the breathing waveform changes from negative to positive, the control console (1) opens the hyperpolarized gas path and closes the expiratory gas path, and the experimental animal inhales hyperpolarized gas autonomously; When the control console (1) detects that the derivative of the breathing waveform changes from positive to negative, the control console (1) opens the expiratory gas path and closes the hyperpolarized gas path, and the experimental animal exhales autonomously. Step 4: During the hyperpolarized gas magnetic resonance imaging scan, when the experimental animal holds its breath, the control console (1) sets the opening and closing of the airway according to the respiratory waveform and the set breath-holding time: when the control console (1) detects that the derivative of the respiratory waveform changes from positive to zero, the control console (1) closes the oxygen airway, the hyperpolarized gas airway, and the expiratory airway, the peak value of the respiratory waveform remains unchanged, and the experimental animal is in a breath-holding state; after the set breath-holding time, the control console (1) opens the expiratory airway, and the experimental animal exhales spontaneously.

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